JP7806773B2 - Charging system and charging method - Google Patents

Description

This disclosure relates to a charging system and a charging method.

Patent Document 1 describes a technology for controlling charging by optimizing the charging rate and charge amount when charging the battery of an electric vehicle used for a trip, so that a necessary and sufficient amount of power is stored by the required departure time. With this technology, the charging rate is determined based on the degree of battery degradation.

JP 2013-090360 A

When away from home, such as on a trip, there is a strong desire to charge the secondary battery, which is the battery to be charged, faster than usual, for example by quickly charging it. However, while the technology described in Patent Document 1 performs charging control that optimizes charging by taking into account the deterioration of the secondary battery, this control is only performed before departure, and therefore it is not possible to optimize charging control while away from home. Furthermore, this issue is not limited to when away from home, and can similarly arise in any situation where there is a desire to charge faster than usual.

This disclosure has been made in consideration of the above-mentioned circumstances, and provides a charging system and charging method that can present a charging pattern that takes into account the degree of deterioration of the secondary battery in situations where there is a desire to charge the secondary battery faster than usual.

The charging system according to the present disclosure includes a control unit that, when charging of a secondary battery at a charging spot is predicted, predicts a first charging time, which is the time required to charge the secondary battery at a first charging rate, and a second charging time, which is the time required to charge the secondary battery at a second charging rate that is faster than the first charging rate, and presents at least the charging pattern that minimizes deterioration of the secondary battery from among a plurality of charging patterns corresponding to a plurality of charging times set between the first charging time and the second charging time.

In the charging method disclosed herein, when a computer predicts that a secondary battery will be charged at a charging spot, the computer predicts a first charging time, which is the time required to charge the secondary battery at a first charging rate, and a second charging time, which is the time required to charge the secondary battery at a second charging rate that is faster than the first charging rate, and presents at least one charging pattern that minimizes deterioration of the secondary battery from among multiple charging patterns corresponding to multiple charging times set between the first charging time and the second charging time.

This disclosure provides a charging system and charging method that can present a charging pattern that takes into account the degree of deterioration of the secondary battery in situations where there is a desire to charge the secondary battery faster than usual.

1 is a block diagram showing a configuration example of a charging system according to a first embodiment; 1. FIG. 4 is a flowchart illustrating an example of a charging pattern presentation process in the charging system of FIG. FIG. 2 is a diagram illustrating an example of correlation information used in the charging system of FIG. 1 . 2 is a schematic diagram showing an example of a presentation image presented by the charging system of FIG. 1; FIG. FIG. 10 is a flow chart for explaining an example of a charging pattern presentation process in the charging system according to the second embodiment. 6 is a flowchart for explaining an example of a charging pattern calculation process in the charging pattern presentation process of FIG. 5 . FIG.

The present invention will be described below through embodiments of the invention, but the claimed invention is not limited to the following embodiments. Furthermore, not all of the configurations described in the embodiments are necessarily essential as means for solving the problem.

(Embodiment 1)
First, an example of a charging system according to the first embodiment (hereinafter referred to as the present system) will be described with reference to Fig. 1. Fig. 1 is a block diagram showing an example of the configuration of the present system.

As shown in FIG. 1, the system 1 may include a charged device 10 equipped with a secondary battery 12 and one or more charging spots 20. Hereinafter, the secondary battery 12 will be referred to as battery 12. The secondary battery 12 may be installed in the charged device 10 in a manner that allows it to be attached or detached by the user, or may be installed in a manner that prevents it from being attached or detached by the user. The following description assumes that the charged device 10 is an electric vehicle, but it may also be a variety of other devices, such as an electric motorcycle, an electrically assisted bicycle, a mobile phone, a smartphone, or a portable personal computer (PC). The charging spot 20 is installed in, for example, a public facility or commercial facility, and is capable of charging the battery 12 of the charged device 10. Of course, the charging system according to this embodiment may also be composed solely of the charged device 10 that can be charged at the charging spot 20.

The charged device 10 may include, for example, a control unit 11 that controls the entire device, a connection unit 13 that connects the battery 12 to the charging spot 20, a display unit 14 consisting of a display device or the like, an input unit 15 consisting of a touch sensor or hardware keys, and a memory unit 16. The charged device 10 includes a load that operates by receiving power from the battery 12.

The control unit 11 can be realized by a computer configured, for example, with a processor such as a CPU (Central Processing Unit), work memory, and non-volatile storage device. A control program to be executed by the processor is stored in this storage device, and the processor reads the control program into the work memory and executes it, thereby enabling the control unit 11 to perform the functions described below. This storage device can also be the memory unit 16. Of course, the control unit 11 may also be configured as a dedicated control circuit.

The charging spot 20 may include a control unit 21 for overall control, a connection unit 22, and a power supply 23 for supplying power to the connection unit 22. The connection unit 22 is an interface that electrically connects to the battery 12 via the connection unit 13, and enables charging of the battery 12 by connecting the connection unit 13 and the connection unit 22 via a wired cable. Of course, instead of using a wired cable, the connection unit 13 and the connection unit 22 may be configured to supply power wirelessly using an electromagnetic induction method, magnetic field resonance method, electric field coupling method, microwave method, laser method, etc.

The functions of the control unit 11 will now be described. When charging of the battery 12 at the charging spot 20 is predicted, the control unit 11 executes the following prediction process and presentation process. The prediction process is a process for predicting a first charging time, which is the time required to charge the battery 12 at a first charging rate, and a second charging time, which is the time required to charge the battery 12 at a second charging rate that is faster than the first charging rate. The first charging time and the second charging time can be defined as the time required to complete charging with normal charging and fast charging, respectively, such as, but not limited to, the maximum charging time and the minimum charging time.

The presentation process is a process of presenting at least one of multiple charging patterns corresponding to multiple charging times set between the first charging time and the second charging time that minimizes deterioration of the battery 12. The multiple charging patterns may be multiple charging patterns in which charging is completed within the multiple charging times set above, but may also include charging patterns that, excluding the condition that charging is completed, allow charging up to a charge capacity that can be used for a specified time or distance, for example, in which case the charge capacity after charging may also be presented.

The information can be presented by at least one of the display unit 14 and an audio output unit (not shown). Each of the multiple charging patterns may be a pattern in which the charging time is performed at a constant charging rate, or a pattern in which the charging rate is changed for each of the periods into which the charging time is further divided, such as a period at a certain charging rate followed by a period at another charging rate.

By providing the above-mentioned information, the above-mentioned charging pattern can be proposed to the user of the charged device 10. The user of the charged device 10 can input an operation from the input unit 15 to indicate whether or not to accept the proposal, and if the operation to accept the proposal is performed, charging can be performed using that charging pattern.

According to this embodiment, in situations where there is a desire to charge the battery faster than usual, a charging pattern can be presented that takes into account the degree of battery deterioration.

Next, an example of the processing performed by the system 1 will be described using Figures 2 to 4. Figure 2 is a flow diagram illustrating an example of the charging pattern presentation process performed by the charging system 1. Figure 3 is a diagram showing an example of correlation information used by the system 1. Figure 4 is a schematic diagram showing an example of a presentation image presented by the system 1.

First, the control unit 11 confirms that the battery 12 is connected to the charging spot 20 by performing a connection determination based on the connection status at the connection unit 13 (step S1). Next, the control unit 11 identifies the charging spot 20 (step S2).

An example of the processing of step S2 is given below. The charged device 10 may be equipped with a location information acquisition unit (not shown) that acquires location information indicating the location of the battery 12 or the location of the charging spot 20. The location information acquisition unit can acquire location information indicating the location of the battery 12 by, for example, acquiring location information indicating the location of the charged device 10 from a global navigation satellite system. Alternatively, the location information acquisition unit may acquire location information of the charging spot 20 from the connection unit 13 while the connection unit 13 is connected to the charging spot 20. Alternatively, the location information acquisition unit may acquire location information indicating the location of the charged device 10 from a global navigation satellite system, for example, and access an information server or map data stored in the memory unit 16 via a communication unit (not shown). The map data may be data used in a navigation system. Through such access, the location information acquisition unit may search for a charging spot 20 located at that location and acquire location information indicating the location of the charging spot 20. When the battery 12 is electrically connected to the charging spot 20, the control unit 11 identifies the charging spot 20 based on the location information acquired by the location information acquisition unit.

The control unit 11 will then predict that charging will be performed at the charge spot 20 identified as described above, and will execute the prediction process and the presentation process. Note that the prediction process and the presentation process do not have to be performed specifically for the identified charge spot 20, but may be performed for charging at the identified charge spot 20, as described here. This enables prediction and presentation that are specific to the identified charge spot 20. In fact, since it is expected that the charging performance of each charge spot 20 will differ from the start or will vary due to deterioration over time or maintenance status, such prediction and presentation can be said to be beneficial.

Next, the control unit 11 acquires the SOC (State Of Charge) and temperature from, for example, the control ECU (Electronic Control Unit) of the battery 12 (step S3). The acquired SOC is an index representing the current charge rate or charging state, and is a value indicating the current charge capacity. The acquired temperature may be the ambient temperature around the battery 12 or the temperature of the battery 12.
For example, since there is a correlation between capacity and voltage, the battery capacity (SOC) can be estimated from the voltage measurement results, but the method for estimating the battery capacity is not limited to this.

The control unit 11 then estimates the maximum charging time P when charging at that charging spot 20 (step S4). For example, if charging has been performed at that charging spot 20 in the past, the control unit 11 estimates the maximum charging time P by referencing the charging time, or by performing analysis using big data on the charging spot 20 or its attributes. Attributes can refer to, for example, the type of facility where the charging spot 20 is installed, such as a highway or shopping mall, or the type of charging spot 20.

The control unit 11 also estimates the minimum charging time Q when charging at that charging spot 20 (step S5). The control unit 11 obtains the minimum charging time Q, determined from the SOC and temperature of the battery 12, as an estimated value from the system of the charged device 10, in this example, the vehicle system. The estimation process example in step S4 can also be applied to step S5 as an alternative or additional process, and the estimation process example in step S5 can also be applied to step S4 as an alternative or additional process. The order of steps S4 and S5 does not matter.

The control unit 11 selects multiple charging times X such that P>X>Q (step S6). The control unit 11 may select multiple charging times X by dividing the period between Q and P equally into a predetermined number of parts or by dividing it at predetermined intervals. For example, if P = 60 (minutes) and Q = 30 (minutes), the control unit 11 may select X = 40 or 50 (minutes). Note that when dividing at predetermined intervals, at least one of the first and last parts may be longer or shorter than the predetermined interval.

In this example, P is the maximum charging time and Q is the minimum charging time, so P>Q. However, if this definition is not adopted, P as the first charging time may be less than Q as the second charging time depending on the estimation method. In that case, multiple charging times X can be selected as charging times such that Q>X>P, or X can be omitted from the selection at all and processing can be performed only on P and Q from then on.

Next, the control unit 11 acquires correlation information 17 from the memory unit 16, which indicates the correlation between the charging rate and the deterioration rate at each temperature and each SOC of the battery 12 (step S7). The memory unit 16 storing the correlation information 17 may be a memory unit included in the vehicle system. The correlation information 17 may include, for each charging rate, a correlation map 30, as shown in FIG. 3, which indicates the correlation between the deterioration rate at each temperature and each SOC for a certain charging rate. Note that the correlation map 30 in FIG. 3 shows a correlation map of the deterioration rate for a charging rate corresponding to charging at a current of 100 A. For example, at a charging rate of 100 A, when the SOC is 50% and the temperature is 20°C, the deterioration rate is 2.0. The correlation map 30 shows an example in which the deterioration rate is indicated by a value in which the larger the numerical value, the greater the degree of deterioration.

In this way, the control unit 11 can refer to the correlation information between the charging rate and the deterioration rate at the current temperature of the battery 12 and the current charge capacity of the battery 12, which is stored for each of the multiple charging rates set between the first charging rate and the second charging rate. The control unit 11 can then determine the charging pattern to present based on the correlation map 30, as described below.

Following step S7, the control unit 11 calculates the charging pattern that minimizes deterioration among the charging times P, Q, and X (step S8). Here, an example is given in which the multiple charging patterns are a charging pattern corresponding to the maximum charging time P and the minimum charging time Q, and one or more charging patterns corresponding to one or more charging times X. However, the charging patterns corresponding to the maximum charging time P and the minimum charging time Q may be excluded because they are extreme patterns. For example, the control unit 11 first calculates, for each of the charging times P, Q, and X, a combination of charging rates that minimizes the deterioration rate from the correlation information 17. The pattern that minimizes deterioration for a certain charging time can be calculated as the combination that minimizes the sum of the numerical values indicated by the correlation information 17, for example, 100 A from the start of charging to 1 minute, 100 A from 1 minute to 2 minutes, and 80 A from 2 minutes to 3 minutes. The control unit 11 then determines the charging pattern resulting in the least deterioration from among the patterns that result in the least deterioration corresponding to each of these charging times P, Q, and X as the charging pattern resulting from the calculation.

The control unit 11 presents the calculated charging pattern that minimizes deterioration to the user (step S9), and then ends the process. When presenting the pattern, it is advisable to include information indicating the charging time and the amount of deterioration. Thereafter, charging can be performed using the charging pattern accepted by the user.

Furthermore, in step S8, the control unit 11 may present, from among the multiple charging patterns, charging patterns in which the degree of deterioration of the battery 12 is below a predetermined level. At this time, information including the degree of battery deterioration and charging time is presented for each corresponding charging pattern. The control unit 11 may, for example, display a presentation image 40 shown in FIG. 4 on the display unit 14. The presentation image 40 includes at least a recommended pattern 41, which has the smallest degree of deterioration among charging times that satisfy the condition of being below a predetermined level. Furthermore, the presentation image 40 may include a balanced pattern 42, which is determined to have the best balance based on the predetermined conditions, among charging times that satisfy the condition of being below a predetermined level, and a fastest pattern 43, which has the greatest degree of deterioration. Here, each pattern 41-43 is displayed including an index indicating the degree of deterioration and information indicating the charging time. The index may be, for example, the sum of the values indicated by the correlation information 17 described above. In this example, the recommended pattern 41 is a charging pattern corresponding to the maximum charging time P. By adopting this presentation method, users can select and charge from among charging patterns that indicate a level of deterioration below a specified level.

Furthermore, as shown in presentation image 40, charging patterns can be presented in an order recommended based on the degree of deterioration, i.e., in ascending order of the degree of deterioration. For example, if the degree of deterioration is defined as levels 1 to 5 in descending order of deterioration, they can be presented as follows. That is, the control unit 11 can present the recommended patterns in order, such as a first charging pattern with a charging time of 30 minutes at level 1, which represents the least degree of deterioration; a second charging pattern with a charging time of 20 minutes at level 2, which represents the next least degree of deterioration; and a third charging pattern with a charging time of 5 minutes at level 5, which represents the most severe degree of deterioration.

This completes the description of this embodiment. In situations where a user desires to charge the battery 12 more quickly than usual, such as when away from home, the system 1 can present a charging pattern that takes into account the degree of battery 12 degradation. In other words, the system 1 can select a charging pattern that has minimal impact on the battery 12 from multiple charging patterns, including rapid charging, and present it to the user. For example, the system 1 can provide the user with suggestions for optimizing rapid charging while away from home. For example, the time required for rapid charging during a trip varies significantly depending on the attributes of the charging location. More specifically, users may tolerate longer charging times at a shopping mall than at a highway service area. The system 1 can present a rapid charging pattern that takes degradation into account and is tailored to the situation of the user of the charged device 10, as in this example. Therefore, the system 1 can prevent situations where a unique charging time is determined, resulting in unnecessary rapid charging and battery degradation.

Furthermore, in the above explanation, it is assumed that there is one charging pattern that minimizes deterioration, and that this one charging pattern corresponds to one of the multiple charging times set for the first charging time and the second charging time. However, the control unit 11 may calculate the charging pattern that minimizes deterioration for each charging time and present the charging pattern that minimizes deterioration for each charging time.

(Embodiment 2)
A second embodiment will be described with reference to Fig. 5 and Fig. 6. Fig. 5 is a flow diagram for describing an example of a charging pattern presentation process in a charging system according to the second embodiment. Fig. 6 is a flow diagram for describing an example of a charging pattern calculation process in the charging pattern presentation process of Fig. 5. The charging system according to the second embodiment differs from the system 1 of Fig. 1 in terms of control content, but will be described with reference to Fig. 1 for convenience. The various examples described in the first embodiment can also be applied to the second embodiment.

In this embodiment, the charged device 10 is equipped with the above-mentioned location information acquisition unit that acquires location information indicating the location of the battery 12. The control unit 11 then searches for candidate charging spots 20 that are reachable with the current charge capacity of the battery 12 and that can charge the battery 12, based on the above-mentioned location information. The search can be performed by referring to the above-mentioned map data. In addition, the search can also acquire information such as the congestion status of each charging spot 20, and search results can include charging spots 20 with congestion levels below a predetermined level. Furthermore, the control unit 11 predicts the first charging time and second charging time for each candidate and presents a charging pattern that will result in at least the above-mentioned minimum.

An example of this charging pattern presentation process will be described below. First, the control unit 11 acquires the location and SOC of the battery 12 (step S11). It searches for reachable charging spots 20 where charging is possible (step S12). Next, based on the search results, the control unit 11 selects one unselected candidate for processing (step S13) and executes a charging pattern calculation process for the selected candidate (step S14). In step S14, the control unit 11 predicts the SOC and temperature upon arrival at that candidate (step S21), and executes the same processes as steps S4 to S8 in Figure 2 for that candidate (steps S22 to S26).

After processing step S14, the control unit 11 determines whether processing of all candidates has been completed (step S15), and if NO, returns to step S13. If the answer is YES in step S15, the control unit 11 presents the charging pattern calculated for each candidate to the user (step S16) and determines whether a candidate has been selected from the input unit 15 (step S17). If the answer is NO in step S17, the control unit 11 ends processing. If the answer is YES in step S17, the control unit 11 uses a navigation system or the like to guide the user to the selected candidate charging spot 20, and charges using the calculated charging pattern when connected to that charging spot 20 (step S18), and ends processing.

By having the control unit 11 perform this type of control, the system 1 can present candidate charging spots 20 in advance, for example, before arriving at the charging spot 20, while taking into account the degree of deterioration of each candidate.

In addition, in this example, the control unit 11 predicts the charging capacity at the time of arrival at each candidate and the start of charging based on, for example, distance and congestion, taking into account that the current charging capacity will be reduced by a different amount depending on the candidate due to power consumption during travel.The control unit 11 can then perform the prediction process and the presentation process based on this charging capacity.

Furthermore, in this example, the prediction process and the presentation process may be performed to produce the same results regardless of the charging capacity of the charging spot 20, or may be performed for charging at each candidate charging spot 20. This allows prediction and presentation that are specialized for each candidate, taking into account the charging capacity of each candidate.

Furthermore, the above-mentioned program includes a set of instructions (or software code) that, when loaded into a computer, causes the computer to perform one or more functions described in the embodiments. The program may be stored on a non-transitory computer-readable medium or a tangible storage medium. By way of example and not limitation, computer-readable media or tangible storage media include random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drive (SSD) or other memory technologies, CD-ROM, digital versatile disc (DVD), Blu-ray (registered trademark) disc or other optical disk storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage device. The program may also be transmitted on a temporary computer-readable medium or communication medium. By way of example and not limitation, temporary computer-readable media or communication media include electrical, optical, acoustic, or other forms of propagated signals.

Note that the present invention is not limited to the above-described embodiment, and modifications can be made as appropriate without departing from the spirit of the present invention. For example, a machine-learned learning model can be used to determine the charging patterns to be presented in the prediction process and presentation process.

1 Charging system, 10 Charged device, 11, 21 Control unit, 12 Secondary battery (battery), 13, 22 Connection unit, 14 Display unit, 15 Input unit, 16 Memory unit, 17 Correlation information, 20 Charging spot, 23 Power source

Claims (5)

When it is predicted that charging of the secondary battery will be performed at the charging spot,
predicting a first charging time, which is the time required to charge the secondary battery at a first charging rate, and a second charging time, which is the time required to charge the secondary battery at a second charging rate that is faster than the first charging rate;
a control unit that presents at least one charging pattern that minimizes deterioration of the secondary battery from among a plurality of charging patterns corresponding to a plurality of charging times set between the first charging time and the second charging time. the control unit presents information including a degree of deterioration of the secondary battery and a charging time for a charging pattern in which a degree of deterioration of the secondary battery is equal to or less than a predetermined degree, among the plurality of charging patterns.
The charging system of claim 1 . a location information acquisition unit that acquires location information indicating a location of the secondary battery or the charging spot,
the control unit, when the secondary battery is electrically connected to the charging spot, identifies the charging spot based on the location information, predicts that charging will be performed at the identified charging spot, predicts the first charging time and the second charging time, and presents a charging pattern that will result in at least the minimum charging time.
3. The charging system according to claim 1 or 2. a location information acquisition unit that acquires location information indicating a location of the secondary battery;
the control unit searches for candidate charging spots that can be reached with the current charge capacity of the secondary battery and that can charge the secondary battery based on the location information, and predicts the first charging time and the second charging time for each of the candidates, and presents a charging pattern that will result in at least the minimum charging time.
3. The charging system according to claim 1 or 2. The computer
When it is predicted that charging of the secondary battery will be performed at the charging spot,
predicting a first charging time, which is the time required to charge the secondary battery at a first charging rate, and a second charging time, which is the time required to charge the secondary battery at a second charging rate that is faster than the first charging rate;
presenting at least one charging pattern that minimizes deterioration of the secondary battery from among a plurality of charging patterns corresponding to a plurality of charging times set between the first charging time and the second charging time;
Charging method.