JP7740980B2 - COMMUNICATION UNIT, BATTERY CONDITION DETECTION DEVICE, INFORMATION PROCESSING SYSTEM, AND DATA COLLECTION METHOD - Google Patents

Description

The technology disclosed in this application relates to a communication unit, a battery state detection device, an information processing system, and a data collection method.

Patent Document 1 describes a secondary battery charging control device. The secondary battery charging control device determines whether the secondary battery will be able to start in the future and notifies the user of the determination result via a mobile terminal.

Patent document 2 describes a rechargeable battery status detection device that transmits usage mode information to a cloud server. The cloud server determines the SOH based on the usage mode information and provides it to the rechargeable battery status detection device.

JP 2015-182518 A Japanese Patent Application Laid-Open No. 2021-093359

The devices described in Patent Documents 1 and 2 are equipped with a built-in communication unit for communicating with the outside world.

However, the technology described in Patent Document 1 is not compatible with secondary battery charging control devices that do not have a communication unit. Therefore, for vehicles equipped with a secondary battery charging control device that does not have a communication unit, the secondary battery charging control device itself must be replaced with a secondary battery charging control device that does have a communication unit, which increases the financial burden on users.

The objective of the technology disclosed in this application is to increase the convenience of battery status detection units while suppressing increases in cost.

According to a first feature, the communication unit includes a first connection unit, an information communication unit, and a wireless communication unit. The first connection unit is configured to be attached to a battery condition detection unit configured to detect battery condition information indicating the condition of a rechargeable battery mounted on a vehicle, and is electrically connected to the battery condition detection unit while attached to the battery condition detection unit. The information communication unit is configured to acquire the battery condition information from the battery condition detection unit via the first connection unit. The wireless communication unit is configured to wirelessly transmit the battery condition information acquired by the information communication unit to an external device.

In the communication unit according to the first feature, the first connection part is configured to be removably attached to the battery condition detection unit, so the communication unit can be attached to the battery condition detection unit via the first connection part. Therefore, the communication unit can be attached to an existing battery condition detection unit, thereby increasing the convenience of the battery condition detection unit while suppressing increases in cost.

According to a second feature, in the communication unit according to the first feature, the information communication unit includes a first wired communication unit and a second wired communication unit. The first wired communication unit is configured to receive battery status information from the battery status detection unit via a wired connection via the first connection unit. The second wired communication unit is configured to transmit battery status information to the vehicle's onboard controller via a wired connection.

The communication unit according to the second feature can transmit battery status information not only to an external device but also to an on-board controller. This allows battery status information to be transmitted to an external device while maintaining control of the vehicle using the battery status information.

According to a third feature, the communication unit according to the second feature further includes a second connection unit. The second connection unit is electrically connectable to the vehicle controller. The second wired communication unit is configured to transmit battery status information to the vehicle controller via a wired connection via the second connection unit.

In the communication unit according to the third feature, the second connection section ensures reliable connection with the vehicle controller.

According to a fourth feature, in the communication unit according to the third feature, the shape of the second connection portion is complementary to the shape of the first connection portion.

In the communication unit according to the fourth feature, a component (e.g., a harness) connectable to the second connection portion can be directly connected to the battery condition detection unit. Therefore, it is possible to achieve both a configuration in which the vehicle's wire harness is directly connected to the battery condition detection unit and a configuration in which the vehicle's wire harness is connected to the battery condition detection unit via the communication unit.

According to a fifth feature, in the communication unit according to any one of the second to fourth features, the first wired communication unit is configured to receive battery status information from the battery status detection unit via the first connection unit via a wired connection using a first protocol. The second wired communication unit is configured to transmit battery status information to the in-vehicle controller via a wired connection using a second protocol different from the first protocol.

The communication unit according to the fifth feature can send and receive information related to battery status detection between networks with different protocols.

According to a sixth feature, in the communication unit according to any one of the second to fifth features, the wireless communication unit is configured to wirelessly receive reference information related to battery state detection from an external device. The information communication unit transmits the reference information received by the wireless communication unit to at least one of the on-board controller and the battery state detection unit.

The communication unit according to the sixth feature transmits reference information acquired from an external device to at least one of the vehicle controller and the battery status detection unit, thereby updating the information according to the rechargeable battery and improving the accuracy of the battery status information.

According to a seventh feature, in the communication unit according to any one of the first to sixth features, the wireless communication unit is configured to perform wireless communication according to at least one of the Bluetooth standard and the Wi-Fi standard.

The communication unit according to the seventh feature allows versatile user terminals such as smartphones and tablet computers to be used as external devices. This increases the convenience of the battery status detection device.

According to an eighth feature, in the communication unit according to any one of the first to seventh features, the wireless communication unit is configured to upload battery status information acquired by the information communication unit to a server.

In the communication unit according to the eighth feature, battery status information acquired from multiple battery status detection devices is analyzed by a server, allowing the battery status information to be effectively utilized to improve the accuracy of battery status detection.

According to a ninth feature, the communication unit according to any one of the first to eighth features further includes a housing that houses the information communication unit. The housing includes a rotation-preventing portion that can come into contact with a side surface of the rechargeable battery.

The communication unit according to the ninth feature stabilizes the position of the communication unit relative to the rechargeable battery.

According to a tenth feature, a battery state detection device includes a battery state detection unit and a communication unit according to any one of the first to ninth features. The battery state detection unit includes a battery connection unit, a voltage sensor, a current sensor, a temperature sensor, and an estimation unit. The battery connection unit is attachable to a terminal of the rechargeable battery. The voltage sensor is configured to measure the voltage of the rechargeable battery. The current sensor is configured to measure the current of the rechargeable battery. The temperature sensor is configured to measure the temperature of the rechargeable battery. The estimation unit is configured to estimate the state of the rechargeable battery based on at least one of the voltage measured by the voltage sensor, the current measured by the current sensor, and the temperature measured by the temperature sensor. The information communication unit of the communication unit is configured to acquire at least one of the measured voltage, the measured current, the measured temperature, and the estimation result of the estimation unit as battery state information via the first connection unit.

In the battery status detection device according to the tenth feature, even if the battery status detection unit does not have a wireless transmission function, by connecting a communication unit to the battery status detection unit, battery status information can be transmitted wirelessly to an external device via the communication unit. Therefore, the communication unit increases the convenience of the battery status detection unit.

According to an eleventh feature, in the battery state detection device according to the tenth feature, the battery state detection unit includes a discharge circuit. The estimation unit is configured to determine the components that make up an equivalent circuit of the rechargeable battery based on a response when a pulsed current is passed through the discharge circuit. The estimation unit is configured to estimate the state of the rechargeable battery based on the components that make up the equivalent circuit.

The battery state detection device according to the eleventh feature can improve the accuracy of estimating battery state information by estimating based on an equivalent circuit model that utilizes pulse discharge.

According to a twelfth feature, in the battery state detection device according to the tenth or eleventh feature, the wireless communication unit is configured to wirelessly receive reference information related to battery state detection from an external device. The estimation unit is configured to correct estimation processing information related to estimation of the state of the rechargeable battery based on the reference information.

In the battery state detection device according to the twelfth feature, by using reference information, the estimation process information can be corrected according to the rechargeable battery, thereby improving the detection accuracy of battery state information.

According to a thirteenth feature, in the battery state detection device according to the twelfth feature, the reference information includes at least one of battery identification information capable of identifying the rechargeable battery, electrical equipment information relating to electrical equipment retrofitted to the vehicle, user usage information relating to at least one of the user's vehicle usage frequency and vehicle usage method, and history information relating to at least one of the rechargeable battery replacement history and reconnection history.

The battery status detection device according to the thirteenth feature can further improve the accuracy of battery status detection by using at least one of battery identification information, electrical equipment information, user usage information, and history information.

According to a fourteenth feature, an information processing system includes a communication unit according to any one of the first to ninth features, a user terminal configured to communicate wirelessly with a wireless communication unit of the communication unit, and a server configured to be connected to the communication unit and the user terminal via the Internet.

In the information processing system according to the fourteenth feature, the communication unit and user terminal are connected to the server via the Internet, allowing battery status information to be sent to the server for effective use.

According to a fifteenth feature, the data collection method includes the steps of acquiring battery status information using a battery status detection device configured to detect the status of a rechargeable battery mounted on a vehicle, transmitting the battery status information to a user terminal using the battery status detection device, inquiring of a user using the user terminal as to whether or not to allow uploading of the battery status information, and uploading the battery status information to a server using the user terminal if the user allows uploading.

In the data collection method according to the fifteenth feature, the communication unit and user terminal are connected to the server via the Internet, allowing battery status information to be sent to the server for effective use.

The technology disclosed in this application makes it possible to increase the convenience of battery status detection units while suppressing increases in costs.

1 is a schematic block diagram of an information processing system including a battery state detection device. 1 is a schematic block diagram of a battery state detection device and an external device. FIG. 2 is an exploded perspective view of the battery state detection device. 1 is an example of an equivalent circuit diagram of a rechargeable battery. FIG. 10 is a diagram showing constants for each battery size. FIG. 10 is a diagram showing correction coefficients for each usage mode. FIG. 10 is a diagram showing standard values of dark current for each vehicle model and grade. FIG. 10 is a diagram showing standard dark current values for each electrical component. FIG. 10 is a diagram showing the relationship between dark current and voltage drop value for each battery type. 4 is a flowchart of the operation of the battery state detection device and the information processing system. 4 is a flowchart of the operation of the battery state detection device and the information processing system. FIG. 10 is a schematic block diagram of a battery state detection device and an external device according to a modified example.

Embodiments will be described below with reference to the drawings. The same reference numerals in the drawings indicate corresponding or identical components.

As shown in FIG. 1, vehicle 2 includes a rechargeable battery 4, an engine 5, a starter motor 6, an alternator 7, a load 8, and a battery state detection device 10. In this embodiment, engine 5 is configured to generate driving force for vehicle 2 and includes, for example, an internal combustion engine such as a gasoline engine or a diesel engine. However, vehicle 2 may also be a hybrid vehicle equipped with an engine (internal combustion engine) and a vehicle drive motor as a power source, or an electric vehicle or fuel cell vehicle equipped with a vehicle drive motor as a power source. Therefore, for example, vehicle 2 may also include a vehicle drive battery in addition to rechargeable battery 4. Vehicle 2 is not limited to the illustrated vehicle.

Examples of the rechargeable battery 4 include a lead-acid battery, a nickel-cadmium battery, a nickel-metal hydride battery, and a lithium-ion battery. The rechargeable battery 4 is configured to be electrically connected to a starter motor 6, an alternator 7, and a load 8. The starter motor 6 is connected to the engine 5 to start the engine 5. The starter motor 6 operates using electricity supplied from the rechargeable battery 4. The alternator 7 is connected to the engine 5 to generate electricity using the driving force generated by the engine 5. The alternator 7 includes, for example, an AC circuit that generates AC power using the driving force of the engine 5, and a rectifier circuit that converts the AC power into DC power. The DC power generated by the alternator 7 charges the rechargeable battery 4.

The load 8 includes, for example, at least one of an electronic control unit (ECU), a harness, a user interface, a light, a heater, a camera, an electric steering motor, a defogger, an ignition coil, a car audio device, and a car navigation device. The load 8 operates using electricity supplied from the rechargeable battery 4. In this embodiment, the load 8 includes an on-board controller 8A and a wire harness 8B. The on-board controller 8A is a type of electronic control unit.

As shown in FIG. 1, the battery condition detection device 10 includes a battery condition detection unit 20 and a communication unit 30. The battery condition detection unit 20 is configured to detect battery condition information indicating the condition of the rechargeable battery 4 installed in the vehicle 2. The battery condition information includes, for example, at least one of the voltage, current, temperature, charging rate (SOC: State of Charge), and degradation state (SOH: State of Health) of the rechargeable battery 4. The communication unit 30 is configured to transmit the battery condition information to an external device 40. The communication unit 30 is separate from the battery condition detection unit 20. In this embodiment, the communication unit 30 is configured to be removably attached to the battery condition detection unit 20. However, the communication unit 30 may also be configured to be unable to be removed from the battery condition detection unit 20 after being attached to the battery condition detection unit 20.

The battery state detection unit 20 includes a sensor 22 and an estimation unit 23. That is, the battery state detection device 10 is equipped with a sensor 22 and an estimation unit 23. The sensor 22 measures at least one of the voltage, current, and temperature of the rechargeable battery 4 installed in the vehicle 2. The estimation unit 23 is configured to estimate the state of the rechargeable battery 4 based on the measurement value of the sensor 22. The sensor 22 includes a voltage sensor 22A, a current sensor 22B, and a temperature sensor 22C. That is, the battery state detection unit 20 includes a voltage sensor 22A, a current sensor 22B, and a temperature sensor 22C.

The voltage sensor 22A is configured to measure the voltage of the rechargeable battery 4. The current sensor 22B is configured to measure the current of the rechargeable battery 4. The temperature sensor 22C is configured to measure the temperature of the rechargeable battery 4. The estimation unit 23 is configured to estimate the state of the rechargeable battery 4 based on at least one of the voltage measured by the voltage sensor 22A, the current measured by the current sensor 22B, and the temperature measured by the temperature sensor 22C.

The communication unit 30 includes a first connection portion 31 and a communication portion 32. That is, the battery state detection device 10 has the communication portion 32. The communication portion 32 is electrically connected to the first connection portion 31. The communication portion 32 includes an information communication portion 33 and a wireless communication portion 34. That is, the communication unit 30 has the first connection portion 31, the information communication portion 33, and the wireless communication portion 34.

The first connection unit 31 is configured to be attached to the battery state detection unit 20. The first connection unit 31 is electrically connected to the battery state detection unit 20 when attached to the battery state detection unit 20. The information communication unit 33 is configured to acquire battery state information from the battery state detection unit 20 via the first connection unit 31.

In this embodiment, the first connection portion 31 is configured to be removably attached to the battery condition detection unit 20. However, the first connection portion 31 may also be configured so that it cannot be removed from the battery condition detection unit 20 after it has been attached to the battery condition detection unit 20.

The wireless communication unit 34 is configured to wirelessly transmit the battery status information acquired by the information communication unit 33 to the external device 40. The wireless communication unit 34 is configured to perform wireless communication according to at least one of the Bluetooth (registered trademark) standard and the Wi-Fi (registered trademark) standard. In this embodiment, the wireless communication unit 34 is configured to perform wireless communication according to the Bluetooth standard and the Wi-Fi standard. However, the wireless communication unit 34 may also be configured to perform wireless communication according to only one of the Bluetooth standard and the Wi-Fi standard. The wireless communication unit 34 may also be configured to perform wireless communication according to a communication standard other than the Bluetooth standard and the Wi-Fi standard.

The external device 40 includes at least one of a user terminal 41 and a server 42. In this embodiment, the external device 40 includes a user terminal 41 and a server 42. Examples of the user terminal 41 include a smartphone and a tablet computer. The wireless communication unit 34 is configured to perform wireless communication with the user terminal 41 using the Bluetooth standard. The wireless communication unit 34 is configured to perform wireless communication with the server 42 using the Wi-Fi standard via the Internet. However, the wireless communication unit 34 may also be configured to perform wireless communication with the user terminal 41 using a communication standard other than the Bluetooth standard. The wireless communication unit 34 may also be configured to perform wireless communication with the server 42 using a communication standard other than the Wi-Fi standard. Furthermore, the external device 40 may include only one of the user terminal 41 and the server 42, or may include devices other than the user terminal 41 and the server 42.

The information communication unit 33 of the communication unit 30 is configured to acquire at least one of the measured voltage, measured current, measured temperature, and the estimation result of the estimation unit 23 as battery state information via the first connection unit 31. In this embodiment, the information communication unit 33 is configured to acquire the measured voltage, measured current, measured temperature, and the estimation result of the estimation unit 23 as battery state information via the first connection unit 31. However, the battery state information acquired by the information communication unit 33 is not limited to the measured voltage, measured current, measured temperature, and the estimation result of the estimation unit 23. The information communication unit 33 may be configured to acquire at least one of the measured voltage, measured current, measured temperature, and the estimation result of the estimation unit 23 as battery state information via the first connection unit 31.

The information processing system 50 includes a battery status detection device 10, a user terminal 41, and a server 42. That is, the information processing system 50 includes a communication unit 30, a user terminal 41, and a server 42. The information processing system 50 is configured to collect battery status information and update information used for battery status detection (reference information described below).

The user terminal 41 is configured to communicate wirelessly with the communication unit 32 of the battery state detection device 10. The user terminal 41 is configured to communicate wirelessly with the wireless communication unit 34 of the communication unit 30. The server 42 is configured to be connected to the battery state detection device 10 and the user terminal 41 via the Internet. The server 42 is configured to be connected to the communication unit 30 and the user terminal 41 via the Internet.

The battery state detection device 10 is configured to transmit battery state information to a server 42 via a user terminal 41 and the Internet. The user terminal 41 is configured to transmit battery state information to the server 42 via the Internet. The battery state detection device 10 is configured to receive update information from the server 42 via the Internet. The user terminal 41 is configured to receive update information from the server 42 via the Internet.

The battery state detection unit 20 includes a discharge circuit 24. The discharge circuit 24 is configured to discharge the rechargeable battery 4. For example, the discharge circuit 24 is configured to pulse discharge the rechargeable battery 4. The discharge circuit 24 includes, for example, a semiconductor switch and a resistance element connected in series. The estimation unit 23 is configured to control the on/off of the semiconductor switch of the discharge circuit 24. The discharge circuit 24 intermittently discharges the rechargeable battery 4 by the estimation unit 23 controlling the on/off of the semiconductor switch. The estimation unit 23 is configured to determine the components that make up an equivalent circuit of the rechargeable battery 4 based on the response when a pulsed current is passed through the discharge circuit 24. The estimation unit 23 is configured to estimate the state of the rechargeable battery 4 based on the components that make up the equivalent circuit.

As shown in FIG. 2, the estimation unit 23 includes, for example, a processor 23P, a memory 23M, a circuit board 23C, and a bus 23B. The processor 23P includes, for example, a CPU (Central Processing Unit) and/or an MPU (Micro Processing Unit). The memory 23M includes, for example, volatile and/or non-volatile memory. Examples of volatile memory include RAM (Random Access Memory). Examples of non-volatile memory include ROM (Read Only Memory), EEPROM (Electrically Erasable Programmable ROM), and flash memory. The processor 23P and the memory 23M are electrically mounted on the circuit board 23C. The processor 23P and the memory 23M are electrically connected to each other via the circuit board 23C and the bus 23B. The sensor 22 and the discharge circuit 24 are electrically connected to the processor 23P and the memory 23M via the circuit board 23C and the bus 23B, respectively. The memory 23M is configured to store a program. The algorithm of the estimation unit 23 is realized by the processor 23P reading and executing the program. However, the structure of the estimation unit 23 is not limited to the above structure. The algorithm of the estimation unit 23 may be realized by hardware alone, or by a combination of software and hardware. The estimation unit 23 may also be referred to as an estimation circuit 23 or an estimation circuit configuration 23.

The information communication unit 33 includes, for example, a processor 33P, memory 33M, a circuit board 33C, and a bus 33B. The processor 33P includes, for example, a CPU and/or an MPU. The memory 33M includes, for example, volatile and/or non-volatile memory. Examples of volatile memory include RAM. Examples of non-volatile memory include ROM, EEPROM, and flash memory. The processor 33P and memory 33M are electrically mounted on the circuit board 33C. The processor 33P and memory 33M are electrically connected to each other via the circuit board 33C and the bus 33B. The first connection unit 31 and the wireless communication unit 34 are electrically connected to the processor 33P and memory 33M via the circuit board 33C and the bus 33B, respectively. The memory 33M is configured to store a program. The algorithm of the information communication unit 33 is realized by the processor 33P reading and executing the program. However, the structure of the information communication unit 33 is not limited to the above structure. The algorithm of the information communication unit 33 may be implemented using hardware alone, or a combination of software and hardware. The information communication unit 33 may also be referred to as an information communication circuit 33 or an information communication circuit configuration 33.

The wireless communication unit 34 includes communication circuitry configured to transmit and receive information using a wireless communication protocol. For example, the wireless communication unit 34 includes an antenna, a wireless signal transmission circuit, and a wireless signal reception circuit. That is, the wireless communication unit 34 may also be referred to as a wireless communication circuit 34 or a wireless communication circuit configuration 34.

The information communication unit 33 includes a first wired communication unit 35. The first wired communication unit 35 is configured to receive battery state information from the battery state detection unit 20 via the first connection unit 31 via a wired connection. The first wired communication unit 35 is configured to receive at least one of the measured voltage, measured current, measured temperature, and the estimation result of the estimation unit 23 as battery state information from the battery state detection unit 20 via the first connection unit 31 via a wired connection. In this embodiment, the first wired communication unit 35 is configured to receive the measured voltage, measured current, measured temperature, and the estimation result of the estimation unit 23 as battery state information from the battery state detection unit 20 via the first connection unit 31 via a wired connection. However, the battery state information acquired by the first wired communication unit 35 is not limited to the measured voltage, measured current, measured temperature, and the estimation result of the estimation unit 23. The first wired communication unit 35 can be configured to acquire at least one of the measured voltage, measured current, measured temperature, and the estimation result of the estimation unit 23 as battery state information via the first connection unit 31.

The information communication unit 33 includes a second wired communication unit 36. The second wired communication unit 36 is configured to transmit battery status information via a wired connection to the on-board controller 8A of the vehicle 2. The communication unit 30 further includes a second connection unit 37 that can be electrically connected to the on-board controller 8A. The second wired communication unit 36 is configured to transmit battery status information via a wired connection to the on-board controller 8A via the second connection unit 37.

The second wired communication unit 36 is configured to transmit at least one of the measured voltage, measured current, measured temperature, and the estimation result of the estimation unit 23 as battery state information via a wired connection to the on-board controller 8A of the vehicle 2 via the second connection unit 37. In this embodiment, the second wired communication unit 36 is configured to transmit the measured voltage, measured current, measured temperature, and the estimation result of the estimation unit 23 as battery state information via a wired connection to the on-board controller 8A of the vehicle 2 via the second connection unit 37. However, the battery state information transmitted by the second wired communication unit 36 may include at least one of the measured current, measured temperature, and the estimation result of the estimation unit 23. The second wired communication unit 36 may be configured to transmit at least one of the measured voltage, measured current, measured temperature, and the estimation result of the estimation unit 23 as battery state information via a wired connection to the on-board controller 8A of the vehicle 2 via the second connection unit 37.

The load 8 includes a system connection portion 8C. The second connection portion 37 is configured to be removably connected to the system connection portion 8C. The second connection portion 37 is electrically connectable to the system connection portion 8C. The system connection portion 8C is provided at the end of the wire harness 8B.

As shown in FIG. 2 , the first wired communication unit 35 is configured to receive battery status information via a wired connection from the battery status detection unit 20 via the first connection unit 31 using a first protocol. The second wired communication unit 36 is configured to transmit battery status information via a wired connection to the in-vehicle controller 8A using a second protocol different from the first protocol. The first wired communication unit 35 includes a communication circuit configured to transmit and receive information via a wired connection using the first protocol. The second wired communication unit 36 includes a communication circuit configured to transmit and receive information via a wired connection using the second protocol. That is, the first wired communication unit 35 may also be referred to as the first wired communication circuit 35 or the first wired communication circuit configuration 35. The second wired communication unit 36 may also be referred to as the second wired communication circuit 36 or the second wired communication circuit configuration 36.

In this embodiment, the first protocol includes LIN (Local Interconnect Network). The second protocol includes CAN (Controller Area Network). However, the first protocol may include a protocol other than LIN. The second protocol may include a protocol other than CAN.

The battery condition detection unit 20 includes a detection unit connection portion 25. The first connection portion 31 is configured to be removably connected to the detection unit connection portion 25 of the battery condition detection unit 20. The first connection portion 31 is electrically connectable to the detection unit connection portion 25.

The battery state detection unit 20 includes a third wired communication unit 26. The third wired communication unit 26 is electrically connected to the detection unit connection unit 25 and the estimation unit 23. The third wired communication unit 26 is configured to transmit battery state information via a wired connection to the communication unit 30 via the detection unit connection unit 25. The third wired communication unit 26 is configured to transmit battery state information via a wired connection to the communication unit 30 via the detection unit connection unit 25 using a first protocol. The third wired communication unit 26 includes a communication circuit configured to transmit and receive information via a wired connection using the first protocol. That is, the third wired communication unit 26 may also be referred to as a third wired communication circuit 26 or a third wired communication circuit configuration 26.

The battery state detection unit 20 includes a battery connector 21A. The battery connector 21A is attachable to the terminal 4A of the rechargeable battery 4. The battery connector 21A is configured to be removably connected to the terminal 4A of the rechargeable battery 4. The battery connector 21A is electrically connected to the sensor 22, the estimation unit 23, the discharge circuit 24, and the third wired communication unit 26.

As shown in FIG. 3 , the harness 2A of the vehicle 2 is connected to the terminal 4A of the rechargeable battery 4. The terminal 4A of the rechargeable battery 4 includes a stud bolt of the rechargeable battery 4. The battery connection portion 21A and the harness 2A are connected to the terminal 4A of the rechargeable battery 4 with a nut 4N. Electricity is supplied from the rechargeable battery 4 to the load 8 of the vehicle 2 via the harness 2A.

The battery condition detection unit 20 is configured to be attached to the battery post 4B. The battery condition detection unit 20 includes a battery post terminal 2B. The battery post terminal 2B is configured to be removably connected to the battery post 4B.

The shape of the first connection portion 31 is complementary to the shape of the detection unit connection portion 25. For example, the first connection portion 31 includes a first connection hole 31A and a first connection terminal 31B (see Figure 2). The first connection terminal 31B is provided within the first connection hole 31A. The detection unit connection portion 25 includes a connection protrusion 25A and a detection unit terminal 25B (see Figure 2). The detection unit terminal 25B is provided on the connection protrusion 25A. The battery condition detection unit 20 includes a unit housing 27. The connection protrusion 25A protrudes from the unit housing 27. The connection protrusion 25A of the detection unit connection portion 25 is insertable into the first connection hole 31A of the first connection portion 31. With the connection protrusion 25A positioned within the first connection hole 31A, the detection unit terminal 25B contacts the first connection terminal 31B. Therefore, the first connection portion 31 can be electrically connected to the detection unit connection portion 25 of the battery state detection unit 20.

The battery condition detection unit 20 may include a connection hole, and the first connection portion 31 may include a protrusion that can be inserted into the connection hole. The shapes of the first connection portion 31 and the detection unit connection portion 25 may be shapes other than a protrusion and a hole. The shape of the first connection portion 31 does not have to be complementary to the shape of the detection unit connection portion 25.

The shape of the second connection portion 37 is complementary to the shape of the system connection portion 8C of the load 8. For example, the system connection portion 8C includes a system connection hole 8D and a system connection terminal 8E (see FIG. 2). The system connection terminal 8E is provided within the system connection hole 8D. The second connection portion 37 includes a second connection protrusion 37A and a second connection terminal 37B (see FIG. 2). The second connection terminal 37B is provided on the second connection protrusion 37A. The communication unit 30 further includes a housing 38 that houses the information communication section 33. The second connection protrusion 37A protrudes from the housing 38. The second connection protrusion 37A is insertable into the system connection hole 8D of the system connection portion 8C. With the second connection protrusion 37A positioned within the system connection hole 8D, the second connection terminal 37B contacts the system connection terminal 8E. Therefore, the system connection portion 8C is electrically connectable to the second connection portion 37.

The second connection portion 37 may include a connection hole, and the system connection portion 8C may include a protrusion that can be inserted into the connection hole. The shapes of the second connection portion 37 and the system connection portion 8C may be shapes other than a protrusion and a hole. The shape of the second connection portion 37 does not have to be complementary to the shape of the system connection portion 8C.

In this embodiment, the shape of the second connection portion 37 is complementary to the shape of the first connection portion 31. Therefore, the shape of the detection unit connection portion 25 is complementary to the shape of the system connection portion 8C. The communication unit 30 can be removed from the detection unit connection portion 25 and the system connection portion 8C, and the system connection portion 8C can be connected to the detection unit connection portion 25. Specifically, the connection protrusion 25A of the detection unit connection portion 25 can be inserted into the system connection hole 8D of the system connection portion 8C. With the connection protrusion 25A positioned within the system connection hole 8D, the detection unit terminal 24B contacts the system connection terminal 8E. Therefore, the detection unit connection portion 25 of the battery condition detection unit 20 can be electrically connected to the system connection portion 8C. However, the shape of the second connection portion 37 does not have to be complementary to the shape of the first connection portion 31. The shape of the detection unit connection portion 25 does not have to be complementary to the shape of the system connection portion 8C.

The housing 38 includes a rotation prevention portion 38A that can contact the side surface 4C of the rechargeable battery 4. The housing 38 includes a housing main body 38B. The rotation prevention portion 38A protrudes from the housing main body 38B. When the battery status detection unit 20 is attached to the rechargeable battery 4 and the communication unit 30 is attached to the battery status detection unit 20, the rotation prevention portion 38A contacts the side surface 4C of the rechargeable battery 4. Therefore, the rotation prevention portion 38A can limit the rotation of the battery status detection unit 20 and the communication unit 30 relative to the rechargeable battery 4. The rotation prevention portion 38A may be omitted from the housing 38. The rotation prevention portion 38A may also be provided on the battery status detection unit 20.

As shown in Figures 2 and 3, the communication unit 32 is provided separately from at least one of the sensor 22 and the estimation unit 23. The communication unit 32 is configured to be removably attached to at least one of the sensor 22 and the estimation unit 23.

In this embodiment, the communication unit 32 is provided separately from the sensor 22 and the estimation unit 23. The communication unit 32 is configured to be removably attached to the sensor 22 and the estimation unit 23. The housing 38 of the communication unit 30 is configured to be removably attached to the unit housing 27 of the battery condition detection unit 20. Specifically, the first connection portion 31 of the communication unit 30 is configured to be removably attached to the detection unit connection portion 25 of the battery condition detection unit 20. However, when the sensor 22 is separate from the estimation unit 23, the communication unit 32 may be provided separately from one of the sensor 22 and the estimation unit 23, or the communication unit 32 may be configured as an integrated unit with the other of the sensor 22 and the estimation unit 23.

As shown in FIG. 2, the communication unit 32 is configured to acquire reference information related to battery state detection from the external device 40. The wireless communication unit 34 is configured to wirelessly receive the reference information related to battery state detection from the external device 40. The information communication unit 33 transmits the reference information received by the wireless communication unit 34 to at least one of the in-vehicle controller 8A and the battery state detection unit 20. In this embodiment, the communication unit 32 is configured to acquire reference information from the user terminal 41. The wireless communication unit 34 is configured to wirelessly receive the reference information related to battery state detection from the user terminal 41. The information communication unit 33 transmits the reference information received by the wireless communication unit 34 to the in-vehicle controller 8A and the battery state detection unit 20.

The reference information includes at least one of battery identification information that can identify the rechargeable battery, electrical equipment information related to electrical equipment added to the vehicle, user usage information related to at least one of the user's vehicle usage frequency and vehicle usage method, and history information related to at least one of the rechargeable battery replacement history and reconnection history. In this embodiment, the reference information includes battery identification information, electrical equipment information, user usage information, and history information. The reference information also includes vehicle identification information related to the vehicle model and grade. However, the reference information is not limited to the above information.

The battery identification information includes at least one of the standard (e.g., JIS), size, manufacturer, and type of the rechargeable battery 4. Rechargeable battery 4 types include flooded batteries, enhanced flooded batteries (EFBs), and dry batteries (e.g., Absorbed Glass Mat (AGM) batteries). The electrical equipment information includes electrical equipment such as monitors, Electric Toll Collection (ETC) units, and drive recorders.

The user's vehicle usage frequency includes the frequency of vehicle 2 use in a week (how often the engine 5 is started) and the amount of time the vehicle 2 is used per day. The user's vehicle usage method includes, for example, commuting, business, and general household use. The rechargeable battery 4 replacement history indicates whether the rechargeable battery 4 has been replaced with a new battery. The rechargeable battery 4 reconnection history indicates whether the rechargeable battery 4 has been disconnected and reconnected.

The user terminal 41 is configured to accept input of reference information related to battery state detection. Specifically, the user terminal 41 includes a controller 41A, a display 41D, a user interface 41U, a device communication unit 41F, and a case 41E. The case 41E houses the controller 41A and the device communication unit 41F. The controller 41A is electrically connected to the display 41D, the user interface 41U, and the device communication unit 41F, and is configured to control the display 41D, the user interface 41U, and the device communication unit 41F.

The controller 41A includes, for example, a processor 41P, memory 41M, a circuit board 41C, and a bus 41B. The processor 41P includes, for example, a CPU and/or an MPU. The memory 41M includes, for example, volatile and/or non-volatile memory. Examples of volatile memory include RAM. Examples of non-volatile memory include ROM, EEPROM, and flash memory. The processor 41P and memory 41M are electrically mounted on the circuit board 41C. The processor 41P and memory 41M are electrically connected to each other via the circuit board 41C and the bus 41B. The sensor 22 and the discharge circuit 24 are electrically connected to the processor 41P and memory 41M via the circuit board 41C and the bus 41B, respectively. The memory 41M is configured to store a program. The processor 41P reads and executes the program, thereby realizing the algorithm of the controller 41A. However, the structure of the controller 41A is not limited to the above structure. The algorithm of the controller 41A may be implemented solely in hardware, or in a combination of software and hardware. The controller 41A may also be referred to as a control circuit 41A or a control circuit configuration 41A.

The display 41D is configured to display information for inputting reference information. The user interface 41U is configured to accept input of reference information. The user interface 41U includes at least one of a plurality of buttons and a touch panel. In the case of a touch panel, the user interface 41U is provided on the display 41D. The controller 41A is configured to store the reference information input via the user interface 41U.

The terminal communication unit 41F is configured to transmit and receive information wirelessly. The terminal communication unit 41F includes a communication circuit configured to transmit and receive information wirelessly. For example, the terminal communication unit 41F includes an antenna, a wireless signal transmission circuit, and a wireless signal reception circuit. That is, the terminal communication unit 41F may also be referred to as a terminal communication circuit 41F or a terminal communication circuit configuration 41F. The terminal communication unit 41F is configured to wirelessly transmit reference information input via the user interface 41U to the communication unit 30. The wireless communication unit 34 of the communication unit 30 is configured to wirelessly receive reference information from the terminal communication unit 41F of the user terminal 41. The information communication unit 33 of the communication unit 30 stores the reference information received via the wireless communication unit 34 in memory 33M. Note that the structure of the user terminal 41 is not limited to the structure described above. The user terminal 41 may have another structure.

The user can input reference information (battery identification information, electrical equipment information, user usage information, and history information) via the user interface 41U while viewing the information displayed on the display 41D of the user terminal 41. The input reference information is wirelessly transmitted from the user terminal 41 to the communication unit 30, and then transmitted from the communication unit 30 to the battery state detection unit 20. The estimation unit 23 stores the received reference information in memory 23M.

For example, the user can select the manufacturer, model number, and size of the rechargeable battery 4 to be installed in the vehicle 2 via the user interface 41U from multiple manufacturers, model numbers, and sizes displayed on the display 41D. The user can select electrical equipment that has been retrofitted to the vehicle 2 via the user interface 41U from multiple electrical equipment displayed on the display 41D. The user can select the actual frequency and duration of use of the vehicle 2 via the user interface 41U from multiple usage frequencies and usage times displayed on the display 41D. The user can input answers via the user interface 41U to the questions "Have you replaced the battery with a new one?" and "Have you reconnected the battery?" displayed on the display 41D. These answers are included in the reference information.

The battery state detection unit 20 detects the state (SOC and SOH) of the rechargeable battery 4 based on reference information received from the user terminal 41 via the communication unit 30. The estimation unit 23 is configured to correct estimation processing information related to estimating the state of the rechargeable battery 4 based on the reference information. The estimation processing information includes, for example, at least one of an estimation formula and parameters. That is, the estimation unit 23 is configured to correct at least one of the estimation formula and parameters based on the reference information.

As shown in Figure 4, the electrical equivalent circuit of rechargeable battery 4 has components (elements), such as conductive resistance Rohm, reaction resistances Rct1 and Rct2, and electric double layer capacitances C1 and C2. Conductive resistance Rohm is a resistance component corresponding to the conductor elements and electrolyte resistance inside rechargeable battery 4. Reaction resistances Rct1 and Rct2 are resistance components corresponding to the reaction resistance of the active material reaction in the electrodes. Electric double layer capacitances C1 and C2 are capacitance components corresponding to the electric double layer at the interface between the electrode and the electrolyte.

The estimation unit 23 is configured to optimize the element values of the elements that make up the equivalent circuit. The estimation unit 23 is configured to optimize the element values of the elements that make up the equivalent circuit through learning processing. One method for optimizing element values is to estimate an optimal state vector using an extended Kalman filter operation, as described in Japanese Patent No. 4532416, and then update the adjustment parameters of the equivalent circuit to optimal ones based on the estimated state vector.

Specifically, when the rechargeable battery 4 is in a resting state of charging or discharging, the estimation unit 23 calculates the voltage drop value when the rechargeable battery 4 is discharged with a predetermined current pattern, based on an equivalent circuit using adjustment parameters obtained from a state vector in a certain state. For example, the estimation unit 23 controls the discharge circuit 24 to pulse-discharge the rechargeable battery 4. The estimation unit 23 controls the discharge circuit 24 to pulse-discharge the rechargeable battery 4 to achieve the predetermined current pattern.

One method for determining whether charging or discharging of the rechargeable battery 4 is in a paused state is to use the absolute value |Im| of the measured current. That is, if the absolute value |Im| of the measured current is greater than a predetermined threshold Ith, the estimation unit 23 concludes that charging or discharging is occurring (startup, running state). If the absolute value |Im| is equal to or less than the predetermined threshold Ith, the estimation unit 23 concludes that charging or discharging of the rechargeable battery 4 is in a paused state (a state in which charging or discharging is not actually occurring and only dark current is flowing).

The estimation unit 23 updates the state vector so that the voltage drop value approaches the actual measured value. The estimation unit 23 calculates optimal adjustment parameters from the updated state vector and calculates the element values of the elements that make up the equivalent circuit based on the constants and the optimized adjustment parameters. Note that the method for optimizing the element values of the elements that make up the equivalent circuit may also be other methods, such as least-squares calculations or an appropriately trained neural network.

The SOH of the rechargeable battery 4 can be estimated by substituting the element values of the conductive resistance Rohm, the reaction resistances Rct1 and Rct2, and the electric double layer capacitances C1 and C2 into the following first estimation equation (1).

SOH=f(Rohm, Rct1, Rct2, C1, C2)...(1)
However, the constants used for optimization differ depending on the size of the rechargeable battery 4. Therefore, the estimation unit 23 is configured to correct the components that make up the equivalent circuit based on the reference information. Specifically, the estimation unit 23 is configured to correct the components that make up the equivalent circuit based on the battery identification information. The estimation unit 23 obtains constants for optimizing the element values of the elements that make up the equivalent circuit based on the size included in the battery identification information.

For example, as shown in FIG. 5, the estimation unit 23 stores multiple constants corresponding to multiple sizes in memory 23M. As described above, the size of the rechargeable battery 4 to be installed in the vehicle 2 (i.e., to which the battery state detection unit 20 is connected) is input to the user terminal 41 and transmitted to the battery state detection unit 20 via the communication unit 30. The estimation unit 23 stores the received size in memory 23M. The estimation unit 23 selects a constant corresponding to the size input to the user terminal 41 from the multiple constants stored in memory 23M. Based on the selected constant, the estimation unit 23 calculates the element values of the components that make up the equivalent circuit using the method described above. In other words, the estimation unit 23 corrects the components that make up the equivalent circuit based on the selected constant. This enables a more accurate estimation of the SOH of the rechargeable battery 4.

The estimation unit 23 is also configured to select correction coefficients for correcting the components that make up the equivalent circuit based on the user usage information. The estimation unit 23 is configured to select correction coefficients for correcting the components that make up the equivalent circuit based on the user usage information received from the user terminal 41 via the communication unit 30.

The user terminal 41 is configured to accept input of user usage information. The user usage information includes, for example, the frequency with which the vehicle 2's engine 5 is started (e.g., once a week, twice a week, five times a week, daily, etc.) and the average daily usage time of the engine 5. Based on the input user usage information, the usage mode of the vehicle 2 can be classified, for example, into usage modes A to E shown in FIG. 6. Each of usage modes A to E has a threshold value for the engine 5 start frequency and average usage time. By comparing the engine 5 start frequency and average usage time with the threshold values for usage modes A to E, one of usage modes A to E can be selected as the usage mode of the vehicle 2. As described below, usage mode A corresponds to the case where the rechargeable battery 4 has been replaced with a new one. Therefore, usage mode A corresponds to a case where the engine 5 start frequency and average usage time are zero. Note that usage modes may be classified using criteria other than those described above, or may be classified into usage modes with more or less usage modes than usage modes A to E.

The estimation unit 23 calculates a correction coefficient for the first estimation formula (1) described above for each usage mode. The estimation unit 23 stores multiple correction coefficients corresponding to multiple usage modes in memory 23M. As shown in FIG. 6, the estimation unit 23 stores correction coefficients f_Rohm_A, f_Rct1_A, f_Rct2_A, f_Rct1_A, f_C1_A, and f_C2_A corresponding to usage mode A in memory 23M. Since usage mode A corresponds to the case where the rechargeable battery 4 is replaced with a new one, the correction coefficients f_Rohm_A, f_Rct1_A, f_Rct2_A, f_Rct1_A, f_C1_A, and f_C2_A are 1. The estimation unit 23 stores in memory 23M the correction coefficients f_Rohm_B, f_Rct1_B, f_Rct2_B, f_Rct1_B, f_C1_B, and f_C2_B corresponding to usage mode B. The estimation unit 23 stores in memory 23M the correction coefficients f_Rohm_C, f_Rct1_C, f_Rct2_C, f_Rct1_C, f_C1_C, and f_C2_C corresponding to usage mode C. The estimation unit 23 stores in memory 23M the correction coefficients f_Rohm_D, f_Rct1_D, f_Rct2_D, f_Rct1_D, f_C1_D, and f_C2_D corresponding to usage mode D. The estimation unit 23 stores the correction coefficients f_Rohm_E, f_Rct1_E, f_Rct2_E, f_Rct1_E, f_C1_E, and f_C2_E corresponding to usage mode E in memory 23M.

The estimation unit 23 selects a correction coefficient corresponding to the usage mode included in the user usage information received via the communication unit 30 from multiple correction coefficients stored in memory 23M. For example, if the usage mode included in the user usage information is usage mode A, the estimation unit 23 selects correction coefficients f_Rohm_A, f_Rct1_A, f_Rct2_A, f_Rct1_A, f_C1_A, and f_C2_A corresponding to usage mode A. The estimation unit 23 calculates the SOH from equation (1) using the selected correction coefficients. This allows the SOH to be calculated according to the usage mode, making it possible to obtain a highly accurate SOH.

After selecting the correction coefficients, the estimation unit 23 calculates the element values of the elements Rohm, Rct1, Rct2, C1, and C2 of the equivalent circuit through a learning process and applies these values to the first estimation formula (1) to calculate the SOH. The estimation unit 23 also stores the element values of the elements Rohm, Rct1, Rct2, C1, and C2 calculated through the learning process and the SOH in memory 23M.

Specifically, the estimation unit 23 stores initial values Rohmi, Rct1i, Rct2i, C1i, and C2i of the element values of the equivalent circuit in the memory 23M. The estimation unit 23 calculates difference values ΔRohm, ΔRct1, ΔRct2, ΔC1, and ΔC2 between the element values calculated by the learning process and the initial values based on the following equations (3) to (7).
ΔRohm=Rohm-Rohmi...(3)
ΔRct1=Rct1−Rct1i (4)
ΔRct2=Rct2−Rct2i (5)
ΔC1=C1-C1i...(6)
ΔC2=C2-C2i...(7)
When usage mode A is selected, the estimation unit 23 calculates Δα_Rohm, Δα_Rct1, Δα_Rct2, Δα_C1, and Δα_C2 based on the following equations (8) to (12). Note that when one of usage modes B to E is selected, the second terms on the right-hand sides of equations (8) to (12) are replaced with correction coefficients corresponding to the selected usage mode from usage mode B to E.
Δα_Rohm=ΔRohm×f_Rohm_A (8)
Δα_Rct1=ΔRct1×f_Rct1_A (9)
Δα_Rct2=ΔRct2×f_Rct2_A (10)
Δα_C1=ΔC1−C1i×f_C1_A (11)
Δα_C2=ΔC2−C2i×f_C2_A (12)
The estimation unit 23 calculates the SOH of the rechargeable battery 4 based on the following second estimation formula (13): where f() is a predetermined function with Δα_Rohm, Δα_Rct1, Δα_Rct2, Δα_C1, and Δα_C2 as variables.

SOH=f(Δα_Rohm, Δα_Rct1, Δα_Rct2, Δα_C1, Δα_C2) ...(13)
The estimation unit 23 is configured to correct the estimation process or estimation result using the components that make up the equivalent circuit based on the history information. Specifically, when the history information indicates that the rechargeable battery 4 has been replaced, the estimation unit 23 selects usage mode A as the usage mode, thereby correcting each of the correction coefficients described above to 1. In other words, the estimation unit 23 corrects the estimation process using the components that make up the equivalent circuit based on the history information that the rechargeable battery 4 has been replaced.

If the history information indicates that the rechargeable battery 4 has been disconnected and reconnected, the estimation unit 23 requests the user to input user usage information via the user terminal 41, and selects a usage mode based on the newly input user usage information to the user terminal 41. The estimation unit 23 selects a correction coefficient based on the selected usage mode, and corrects the element values of the elements that make up the equivalent circuit based on the selected correction coefficient. In other words, the estimation unit 23 corrects the estimation process using the components that make up the equivalent circuit based on the history information that the rechargeable battery 4 has been disconnected and reconnected.

Furthermore, when the vehicle 2 comes to a halt and the engine 5 is shut off, the operation of the electric steering motor, defogger, ignition coil, car audio, car navigation system, and other components included in the load 8 is stopped, and only electrical equipment added to the vehicle 2 (e.g., a clock, car security system, and battery state detection unit 20) remains operational. Therefore, a weak current (a few mA to several hundred mA) called dark current flows from the rechargeable battery 4 to the load 8. Although it is weak, the dark current affects the measurement of the open circuit voltage (OCV) of the rechargeable battery 4.

On the other hand, a standard value for the dark current of the vehicle 2 before the electrical equipment is retrofitted can also be set in advance based on vehicle-specific information such as the model and grade of the vehicle 2. Furthermore, a standard value for the dark current caused by the retrofitted electrical equipment can be set in advance for each electrical equipment. Therefore, the estimation unit 23 is configured to correct estimation processing information related to the estimation of the state of the rechargeable battery 4 based on the electrical equipment information. Specifically, the estimation unit 23 is configured to correct at least one of the estimation formula and parameters based on the electrical equipment information.

As shown in FIG. 7, the estimation unit 23 pre-stores in memory 23M a plurality of first dark current standard values corresponding to a plurality of vehicle models and grades. The estimation unit 23 acquires the vehicle model and grade from the vehicle identification information received from the user terminal 41 via the communication unit 30 and stores them in memory 23M. The estimation unit 23 selects the dark current standard value corresponding to the vehicle model and grade included in the vehicle identification information from the plurality of first dark current standard values stored in memory 23M.

As shown in FIG. 8, the estimation unit 23 pre-stores in memory 23M a plurality of second dark current standard values corresponding to a plurality of expected electrical components. The estimation unit 23 stores in memory 23M the retrofitted electrical components included in the electrical component information received from the user terminal 41 via the communication unit 30. The estimation unit 23 selects a dark current standard value corresponding to each electrical component included in the electrical component information from the plurality of second dark current standard values stored in memory 23M. The estimation unit 23 calculates the sum of the selected first dark current standard value and the selected second dark current standard value, and stores this as a total dark current value in memory 23M.

The estimation unit 23 pre-stores in memory 23M a third estimation formula that estimates a voltage drop value from a dark current value. The estimation unit 23 calculates the voltage drop value by inputting the total dark current value into the third estimation formula. The estimation unit 23 adds the voltage drop value to the measured voltage to calculate the OCV. The estimation unit 23 stores in memory 23M a fourth estimation formula that is a relational expression between the OCV and the SOC. The estimation unit 23 calculates the SOC based on the OCV and the fourth estimation formula. This allows the SOC to be accurately estimated taking the dark current into account.

However, it is possible that the third estimation formula, which shows the relationship between the dark current value and the voltage drop value, may change depending on the type of rechargeable battery 4. For example, Figure 9 shows a comparison of the measured relationship between the dark current value flowing through three different types of rechargeable batteries 4 and the voltage drop value ΔV, with the rechargeable battery 4 at a temperature of 25°C and an SOC of 100%. In Figure 9, squares, triangles, and diamonds represent the actual measurement results for each of the three battery types, while the solid lines represent the estimated results for each battery type using the aforementioned formula (1). As can be seen from Figure 9, the relationship between the dark current value and the voltage drop value varies depending on the battery type (e.g., specification, capacity, size, manufacturer, state of charge, etc.). Therefore, the estimation unit 23 pre-stores multiple third estimation formulas corresponding to multiple battery types in memory 23M. From the multiple third estimation formulas stored in memory 23M, the estimation unit 23 selects an estimation formula corresponding to the battery type included in the battery identification information received via the communication unit 30. The estimation unit 23 calculates the voltage drop value corresponding to the dark current value based on the selected third estimation formula. By inputting the total dark current value into the selected third estimation formula, the estimation unit 23 can calculate a more accurate voltage drop value. Therefore, the SOC can be estimated more accurately by taking the dark current and battery type into account.

In addition, the battery status information obtained by the battery status detection unit 20 is uploaded to the server 42 and used to improve the estimated accuracy of battery status detection.

Specifically, the battery state detection unit 20 transmits battery state information (e.g., SOC, SOH) acquired from the rechargeable battery 4 to the communication unit 30. The information communication unit 33 of the communication unit 30 acquires the battery state information from the battery state detection unit 20. The wireless communication unit 34 is configured to upload the battery state information acquired by the information communication unit 33 to the server 42. The wireless communication unit 34 is configured to upload the battery state information acquired by the information communication unit 33 to the server 42 via the Internet. The wireless communication unit 34 wirelessly transmits the battery state information acquired by the information communication unit 33 to the user terminal 41. The user terminal 41 uploads the battery state information to the server 42 via the Internet.

The user terminal 41 is configured to inquire of the user of the user terminal 41 whether or not to permit uploading of the battery status information. The controller 41A causes the display 41D to display an inquiry as to whether or not to permit uploading of the battery status information. If the user permits uploading, the terminal communication unit 41F transmits the battery status information to the server 42 via the Internet.

The server 42 is configured to analyze the uploaded battery status information. By collecting and analyzing various battery status information, the server 42 can generate update information to improve the accuracy of the battery status information. The server 42 transmits the update information to the user terminal 41. The user terminal 41 transmits the update information to the battery status detection unit 20 via the communication unit 30. The estimation unit 23 of the battery status detection unit 20 updates the reference information based on the update information and stores the updated reference information in the memory 23M. This improves the accuracy of battery status detection.

The operation of the battery state detection device 10 and the information processing system 50 will be described with reference to Figures 10 and 11.

As shown in FIG. 10, the estimation unit 23 of the battery state detection unit 20 determines whether reference information has been received from the user terminal 41 via the communication unit 30 (step S1). If reference information has been received, the reference information stored in the memory 23M is updated with the newly received reference information (step S2). Specifically, the estimation unit 23 updates the battery identification information, electrical equipment information, user usage information, history information, and vehicle identification information based on the received reference information. If reference information has not been received, the reference information is not updated and processing proceeds to step S3.

The estimation unit 23 corrects the estimation processing information (estimation formula and parameters) based on the reference information (step S3). Specifically, the estimation unit 23 acquires constants for optimizing the element values of the equivalent circuit based on the size included in the battery identification information (step S31). More specifically, the estimation unit 23 selects a constant corresponding to the size included in the battery identification information from among multiple constants stored in memory 23M. Furthermore, the estimation unit 23 selects correction coefficients for correcting the components that make up the equivalent circuit based on the user usage information (step S32). Specifically, the estimation unit 23 selects a correction coefficient corresponding to the usage mode included in the user usage information from among multiple correction coefficients stored in memory 23M.

Based on the historical information, the estimation process or estimation results using the components that make up the equivalent circuit are corrected by the estimation unit 23 (step S33). Specifically, if the historical information indicates that the rechargeable battery 4 has been replaced, the estimation unit 23 selects usage mode A as the usage mode.

The estimation processing information is corrected by the estimation unit 23 based on the vehicle identification information. Specifically, the estimation unit 23 selects a dark current standard value corresponding to the vehicle model and grade included in the vehicle identification information from the multiple first dark current standard values stored in memory 23M (step S34).

The estimation processing information is corrected by the estimation unit 23 based on the electrical equipment information. Specifically, the estimation unit 23 selects a dark current standard value corresponding to the electrical equipment included in the electrical equipment information from multiple second dark current standard values stored in memory 23M (step S35). The estimation unit 23 calculates the sum of the selected first dark current standard value and at least one selected second dark current standard value as the total dark current value (step S36).

The estimation unit 23 selects an estimation formula corresponding to the battery type included in the battery identification information from multiple third estimation formulas (relationship formulas between dark current values and voltage drop values) stored in memory 23M (step S37). The estimation unit 23 calculates the voltage drop value based on the total dark current value and the selected third estimation formula (step S38).

The estimation unit 23 determines whether charging/discharging of the rechargeable battery 4 is in a suspended state (step S39). If charging/discharging of the rechargeable battery 4 is not in a suspended state, steps S1 to S38 are repeated (step S39).

On the other hand, as shown in FIG. 11, when charging and discharging of the rechargeable battery 4 is suspended, the voltage and current of the rechargeable battery 4 are measured by the voltage sensor 22A and the current sensor 22B (step S40). The measured voltage and measured current are temporarily stored in the memory 23M. The OCV is calculated by the estimation unit 23 by adding the voltage drop value to the measured voltage (step S41). The SOC is calculated by the estimation unit 23 based on the OCV and the fourth estimation formula (step S42).

When charging and discharging of the rechargeable battery 4 is paused, the discharge circuit 24 initiates pulse discharging of the rechargeable battery 4 (step S43). The voltage and current of the rechargeable battery 4 are measured by the voltage sensor 22A and the current sensor 22B (step S44). Measurement of the voltage and current is repeated until the pulse discharging ends (step S45). After the pulse discharging ends, the SOC of the rechargeable battery 4 is calculated by the estimation unit 23 using equations (3) to (13) (step S46). The calculated SOC and SOH are transmitted to the on-board controller 8A via the communication unit 30 (step S5).

To collect battery status information from multiple vehicles, the calculated SOC and SOH are uploaded to a server 42 via the Internet (step S6). Specifically, the data collection method includes the steps of acquiring battery status information using a battery status detection device 10 configured to detect the status of a rechargeable battery 4 installed in the vehicle 2 (steps S1 to S46), transmitting the battery status information to a user terminal 41 using the battery status detection device 10 (step S61), inquiring of the user via the user terminal 41 as to whether or not to allow uploading of the battery status information (step S62), and uploading the battery status information to the server 42 by the user terminal 41 if the user allows uploading (step S63). If the user does not allow uploading, the battery status information is not uploaded from the user terminal 41 to the server 42, and the process returns to step S1 (step S62). If the user allows uploading, the latest battery status information is uploaded from the user terminal 41 to the server 42 each time the battery status information is updated (step S63). Note that battery status information may be uploaded to the server 42 via the Internet from the communication unit 30, rather than from the user terminal 41.

(1) As described above, the communication unit 30 includes a first connection unit 31, an information communication unit 33, and a wireless communication unit 34. The first connection unit 31 is configured to be attached to a battery state detection unit 20 configured to detect battery state information indicating the state of the rechargeable battery 4 mounted on the vehicle 2, and is electrically connected to the battery state detection unit 20 while attached to the battery state detection unit 20. The information communication unit 33 is configured to acquire battery state information from the battery state detection unit 20 via the first connection unit 31. The wireless communication unit 34 is configured to wirelessly transmit the battery state information acquired by the information communication unit 33 to the external device 40.

The communication unit 30 is configured so that the first connection portion 31 can be removably attached to the battery condition detection unit 20, allowing the communication unit 30 to be attached to the battery condition detection unit 20 via the first connection portion 31. Therefore, the communication unit 30 can be attached to an existing battery condition detection unit 20, thereby increasing the convenience of the battery condition detection unit 20 while suppressing increases in costs.

(2) The information communication unit 33 includes a first wired communication unit 35 and a second wired communication unit 36. The first wired communication unit 35 is configured to receive battery status information via a wired connection from the battery status detection unit 20 via the first connection unit 31. The second wired communication unit 36 is configured to transmit battery status information via a wired connection to the on-board controller 8A of the vehicle 2. Therefore, battery status information can be transmitted not only to the external device 40 but also to the on-board controller 8A. This allows battery status information to be transmitted to the external device 40 while maintaining control of the vehicle 2 using the battery status information.

(3) The communication unit 30 further includes a second connection unit 37. The second connection unit 37 is electrically connectable to the in-vehicle controller 8A. The second wired communication unit 36 is configured to transmit battery status information via a wire to the in-vehicle controller 8A via the second connection unit 37. Therefore, the second connection unit 37 ensures a reliable connection with the in-vehicle controller 8A.

(4) Because the shape of the second connection portion 37 is complementary to the shape of the first connection portion 31, a component (e.g., a harness) connectable to the second connection portion 37 can be directly connected to the battery condition detection unit 20. Therefore, it is possible to achieve both a configuration in which the vehicle 2's wire harness is directly connected to the battery condition detection unit 20 and a configuration in which the vehicle 2's wire harness is connected to the battery condition detection unit 20 via the communication unit 30.

(5) The first wired communication unit 35 is configured to receive battery status information via a wired connection from the battery status detection unit 20 via the first connection unit 31 using a first protocol. The second wired communication unit 36 is configured to transmit battery status information via a wired connection to the in-vehicle controller 8A using a second protocol that is different from the first protocol. Therefore, information related to battery status detection can be transmitted and received between networks using different protocols.

(6) The wireless communication unit 34 is configured to wirelessly receive reference information related to battery state detection from the external device 40. The information communication unit 33 transmits the reference information received by the wireless communication unit 34 to at least one of the on-board controller 8A and the battery state detection unit 20. By transmitting the reference information obtained from the external device 40 to at least one of the on-board controller 8A and the battery state detection unit 20, the information can be updated according to the rechargeable battery 4, thereby improving the accuracy of the battery state information.

(7) Because the wireless communication unit 34 is configured to perform wireless communication using at least one of the Bluetooth and Wi-Fi standards, a versatile user terminal 41 such as a smartphone or tablet computer can be used as the external device 40. This increases the convenience of the battery state detection device 10.

(8) The wireless communication unit 34 is configured to upload the battery status information acquired by the information communication unit 33 to the server 42. Therefore, by having the server 42 analyze the battery status information acquired from multiple battery status detection devices 10, the battery status information can be effectively utilized to improve the accuracy of battery status detection.

(9) The communication unit 30 further includes a housing 38 that houses the information communication unit 33. The housing 38 includes a rotation-preventing portion that can come into contact with the side of the rechargeable battery 4. This stabilizes the position of the communication unit 30 relative to the rechargeable battery 4.

(10) The battery state detection device 10 includes a battery state detection unit 20 and a communication unit 30 according to any one of the first to ninth features. The battery state detection unit 20 includes a battery connection unit, a voltage sensor, a current sensor, a temperature sensor, and an estimation unit 23. The battery connection unit is attachable to a terminal of the rechargeable battery 4. The voltage sensor is configured to measure the voltage of the rechargeable battery 4. The current sensor is configured to measure the current of the rechargeable battery 4. The temperature sensor is configured to measure the temperature of the rechargeable battery 4. The estimation unit 23 is configured to estimate the state of the rechargeable battery 4 based on at least one of the voltage measured by the voltage sensor, the current measured by the current sensor, and the temperature measured by the temperature sensor. The information communication unit 33 of the communication unit 30 is configured to acquire at least one of the measured voltage, the measured current, the measured temperature, and the estimation result of the estimation unit 23 as battery state information via the first connection unit 31.

In the battery condition detection device 10, even if the battery condition detection unit 20 does not have a wireless transmission function, by connecting the communication unit 30 to the battery condition detection unit 20, battery condition information can be transmitted wirelessly to the external device 40 via the communication unit 30. Therefore, the communication unit 30 increases the convenience of the battery condition detection unit 20.

(11) According to the eleventh feature, in the battery state detection device 10 according to the tenth feature, the battery state detection unit 20 includes a discharge circuit 24. The estimation unit 23 is configured to determine the components that make up the equivalent circuit of the rechargeable battery 4 based on the response when a pulsed current is passed through the discharge circuit 24. The estimation unit 23 is configured to estimate the state of the rechargeable battery 4 based on the components that make up the equivalent circuit. Estimation based on an equivalent circuit model that utilizes pulse discharge can improve the accuracy of estimation of battery state information.

(12) The wireless communication unit 34 is configured to wirelessly receive reference information related to battery state detection from the external device 40. The estimation unit 23 is configured to correct estimation process information related to estimation of the state of the rechargeable battery 4 based on the reference information. By using the reference information, the estimation process information can be corrected according to the rechargeable battery 4, thereby improving the detection accuracy of the battery state information.

(13) The reference information includes at least one of battery identification information that can identify the rechargeable battery 4, electrical equipment information related to electrical equipment retrofitted to the vehicle 2, user usage information related to at least one of the user's vehicle usage frequency and vehicle usage method, and history information related to at least one of the replacement history and reconnection history of the rechargeable battery 4. By using at least one of the battery identification information, electrical equipment information, user usage information, and history information, the accuracy of battery status detection can be further improved.

(14) The information processing system 50 includes a communication unit 30 relating to any one of the first to ninth features, a user terminal 41 configured to communicate wirelessly with the wireless communication unit 34 of the communication unit 30, and a server 42 configured to be connected to the communication unit 30 and the user terminal 41 via the Internet.

In the information processing system 50, the communication unit 30 and user terminal 41 are connected to the server 42 via the Internet, so battery status information can be sent to the server 42 for effective use.

(15) The data collection method includes the steps of acquiring battery state information using a battery state detection device (10) configured to detect the state of a rechargeable battery (4) mounted on a vehicle (2), transmitting the battery state information to a user terminal (41) using the battery state detection device (10), inquiring of a user using the user terminal (41) as to whether or not to allow uploading of the battery state information, and uploading the battery state information to a server (42) using the user terminal (41) if the user allows uploading.

In this data collection method, the communication unit 30 and user terminal 41 are connected to the server 42 via the Internet, so battery status information can be sent to the server 42 for effective use.

In the above-described embodiment, the information communication unit 33 includes the second wired communication unit 36. However, as shown in FIG. 12, the second wired communication unit 36 may be omitted from the information communication unit 33. In this case, the second connection unit 37 is omitted from the communication unit 30. The communication unit 30 according to the modified example shown in FIG. 12 can be attached to a battery status detection unit 20 that does not have a configuration for communicating with an on-board controller. As with the above-described embodiment, in the modified example shown in FIG. 12, the first connection unit 31 may be configured to be removably attached to the battery status detection unit 20, or may be configured so that the first connection unit 31 cannot be removed from the battery status detection unit 20 after being attached to the battery status detection unit 20.

In this application, the terms "comprise" and their derivatives are open-ended terms that describe the presence of elements and do not exclude the presence of other elements not listed. This also applies to the terms "have," "include," and their derivatives.

In this application, ordinal numbers such as "first" and "second" are merely terms for identifying components and do not have any other meaning (such as a particular order). For example, the presence of a "first element" does not imply the presence of a "second element," and the presence of a "second element" does not imply the presence of a "first element."

Words expressing degrees such as "substantially," "about," and "approximately" can mean a reasonable deviation that does not significantly change the final result. All numerical values described in this application can be interpreted to include words such as "substantially," "about," and "approximately."

In addition, the expression "at least one of A and B" in this disclosure includes, for example, (1) A only, (2) B only, and (3) both A and B. The expression "at least one of A, B, and C" includes, for example, (1) A only, (2) B only, (3) C only, (4) A and B, (5) B and C, (6) A and C, and (7) all of A, B, and C. In this disclosure, the expression "at least one of A and B" is not to be interpreted as "at least one of A and at least one of B."

In light of the above disclosure, it is apparent that various modifications and variations of the present invention are possible. Therefore, the present invention may be practiced in a manner different from the specific disclosure of this application without departing from the spirit of the present invention.

2: Vehicle 4: Rechargeable battery 8: Load 8A: In-vehicle controller 8B: Wire harness 10: Battery state detection device 19: Load 20: Battery state detection unit 22: Sensor 22A: Voltage sensor 22B: Current sensor 22C: Temperature sensor 23: Estimation unit 24: Discharge circuit 30: Communication unit 31: First connection unit 32: Communication unit 33: Information communication unit 34: Wireless communication unit 35: First wired communication unit 36: Second wired communication unit 37: Second connection unit 38: Housing 38A: Anti-rotation unit 40: External device 41: User terminal 42: Server 50: Information processing system

Claims (14)

a first connection portion configured to be attached to a battery state detection unit configured to detect battery state information indicating a state of a rechargeable battery mounted on a vehicle, the first connection portion being electrically connected to the battery state detection unit in a state where the first connection portion is attached to the battery state detection unit;
an information communication unit configured to acquire the battery state information from the battery state detection unit via the first connection unit;
a wireless communication unit configured to wirelessly transmit the battery state information acquired by the information communication unit to an external device;
a second connection portion electrically connectable to an on-board controller of the vehicle;
Equipped with
the battery state detection unit includes a detection unit connection portion directly connectable to a system connection portion electrically connected to the on-board controller;
the first connection portion is configured to be detachably connected to the detection unit connection portion, which is directly connectable to the system connection portion;
the second connection portion is configured to be detachably connected to the system connection portion that is directly connectable to the detection unit connection portion;
the information communication unit includes a first wired communication unit and a second wired communication unit;
the first wired communication unit is configured to receive the battery state information from the battery state detection unit via the first connection unit;
the second wired communication unit is configured to transmit the battery state information acquired by the first wired communication unit via the first connection unit to the in-vehicle controller via the second connection unit by wire;
the wireless communication unit is configured to wirelessly transmit the battery state information acquired by the first wired communication unit to the external device via the first connection unit;
Communication unit. Further, a housing for accommodating the information communication unit is provided.
the first connection portion protrudes from the housing;
The second connection portion protrudes from the housing in a direction different from that of the first connection portion.
2. The communication unit of claim 1. The second connection portion protrudes from the housing on a side opposite to the first connection portion.
3. The communication unit of claim 2. the housing includes a housing main body that houses the information communication unit, and a rotation prevention portion that protrudes from the housing main body and is capable of contacting a side surface of the rechargeable battery,
the first connection portion protrudes from the housing body,
the second connection portion protrudes from the housing body in a direction different from that of the first connection portion,
the anti-rotation portion protrudes from the housing main body in a direction different from the first connecting portion and the second connecting portion;
A communication unit according to claim 2 or 3. a shape of the first connection portion is complementary to a shape of the detection unit connection portion;
the second connection portion has a shape complementary to the shape of the system connection portion;
The shape of the second connection portion is complementary to the shape of the first connection portion.
A communication unit according to any one of claims 1 to 4 . the first wired communication unit is configured to receive the battery status information from the battery status detection unit via the first connection unit using a first protocol;
the second wired communication unit is configured to transmit the battery state information to the in-vehicle controller via a wired connection using a second protocol different from the first protocol.
A communication unit according to any one of claims 1 to 5 . the wireless communication unit is configured to wirelessly receive reference information related to battery state detection from the external device;
the information communication unit transmits the reference information received by the wireless communication unit to at least one of the in-vehicle controller and the battery state detection unit;
A communication unit according to any one of claims 1 to 6 . The wireless communication unit is configured to perform wireless communication according to at least one of the Bluetooth standard and the Wi-Fi standard.
A communication unit according to any one of claims 1 to 7 . the wireless communication unit is configured to upload the battery state information acquired by the first wired communication unit to a server;
A communication unit according to any one of claims 1 to 8 . the battery state detection unit;
The communication unit according to any one of claims 1 to 9,
The battery state detection unit
a battery connector attachable to a terminal of the rechargeable battery;
a voltage sensor configured to measure a voltage of the rechargeable battery;
a current sensor configured to measure a current of the rechargeable battery;
a temperature sensor configured to measure a temperature of the rechargeable battery;
an estimation unit configured to estimate a state of the rechargeable battery based on at least one of a voltage measured by the voltage sensor, a current measured by the current sensor, and a temperature measured by the temperature sensor;
the information communication unit of the communication unit is configured to acquire at least one of the measured voltage, the measured current, the measured temperature, and an estimation result of the estimation unit as the battery state information via the first connection unit.
Battery condition detection device. the battery state detection unit includes a discharge circuit;
the estimation unit is configured to determine components that constitute an equivalent circuit of the rechargeable battery based on a response when a pulsed current is passed through the discharge circuit;
the estimation unit is configured to estimate the state of the rechargeable battery based on components that configure the equivalent circuit;
The battery state detection device according to claim 10. the wireless communication unit is configured to wirelessly receive reference information related to battery state detection from the external device;
the estimation unit is configured to correct estimation processing information related to estimation of the state of the rechargeable battery based on the reference information;
12. The battery state detection device according to claim 10 or 11. The reference information is
battery identification information for identifying the rechargeable battery;
Electrical equipment information regarding electrical equipment retrofitted to the vehicle;
user usage information relating to at least one of a frequency of vehicle usage and a method of vehicle usage by the user; and history information relating to at least one of a replacement history and a reconnection history of the rechargeable battery.
The battery state detection device according to claim 12. The communication unit according to any one of claims 1 to 9;
a user terminal configured to wirelessly communicate with the wireless communication unit of the communication unit;
a server configured to be connected to the communication unit and the user terminal via the Internet;
An information processing system comprising :