JP4069720B2 - Overcharge / discharge monitoring device for battery pack - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for monitoring an overcharge state and an overdischarge state of an assembled battery.
[0002]
[Prior art]
In an assembled battery in which a plurality of single cells (hereinafter referred to as cells) are connected in series, a monitoring device that detects that any of the plurality of cells is in an overcharged state or an overdischarged state is known. (For example, refer to Patent Document 1).
[0003]
Prior art documents related to the invention of this application include the following.
[Patent Document 1]
Japanese Patent Laid-Open No. 05-258778
[Problems to be solved by the invention]
However, the conventional overcharge / discharge monitoring device for an assembled battery only detects the overcharge state or overdischarge state of any cell, and the monitoring content is scarce and the optimum response as a system cannot be taken. There's a problem.
[0005]
An object of the present invention is to enhance the contents of monitoring so that an optimum response can be taken as a system.
[0006]
[Means for Solving the Problems]
When an overdischarge state of an assembled battery is detected when an overdischarge state of any cell or cell parallel circuit constituting the assembled battery is detected, the present invention provides a charge / discharge path for the assembled battery by a switch. The battery pack abnormality signal for shutting off the battery is not output, but the discharge inhibition signal is output. On the other hand, over-discharge state of any cell or cells parallel circuit constituting the assembled battery when it is detected, if the over-discharge state of the battery pack is not detected, and outputs the battery pack abnormality signal.
In addition, when an overcharged state of an assembled battery is detected when an overcharged state of any of the cells constituting the assembled battery or the cell parallel circuit is detected, the battery pack is charged by the switch. A charge prohibition signal is output without outputting an assembled battery abnormality signal for interrupting the discharge path . On the other hand, when the overcharge state of any cell or cells parallel circuit constituting the battery pack is detected, if the overcharge state of the battery is not detected, and outputs the battery pack abnormality signal.
[0007]
【The invention's effect】
According to the present invention, it is possible to enhance the contents of monitoring, and to take optimum measures as a system.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment in which the present invention is applied to an assembled battery in which n cells (unit cells) are connected in series will be described. The present invention is not limited to an assembled battery in which a plurality of cells are connected in series, and can also be applied to an assembled battery in which a plurality of cell parallel circuits in which a plurality of cells are connected in parallel are connected in series. . The invention of the present application is not particularly limited with respect to the type of battery. For example, the invention of the present application is applicable to all types of batteries such as manganese-based, cobalt-based, nickel-based lithium ion batteries, and various nickel-hydrogen batteries. Can be applied.
[0009]
<< First Embodiment of the Invention >>
FIG. 1 shows the configuration of the first embodiment. In the assembled battery 1, n cells 11, 12, 13,..., 1n are connected in series. Both ends C0-C1, C1-C2, C2-C3, and Cn-1-Cn of each cell 11 to 1n of the assembled battery 1 include current bypass circuits 21 to 2n, overcharge detection circuits 31 to 3n, and overloads described later. Discharge detection circuits 41 to 4n are connected in parallel.
[0010]
FIG. 2 shows details of the current bypass circuit, the overcharge detection circuit, and the overdischarge detection circuit. These circuits are all common to the cells 11 to 1n. The current bypass circuits 21 to 2n include a current bypass circuit in which a resistor R11 and a transistor (FET) Q1 are connected in series, and a control circuit including a comparator C1, an inverter INV1, and resistors R12 and R13. The comparator C1 compares the cell voltage with the threshold voltage Vc3 obtained by dividing the control power supply voltage Vcc by the resistors R12 and R13.
[Expression 1]
Vc3 = R13 / (R12 + R13) · Vcc
When the cell voltage exceeds the threshold value Vc3, the output of the comparator C1 becomes low level and is inverted to high level by the inverter INV1. Thereby, the transistor Q1 is turned on, and the charging current that has been flowing to the cell until then flows through the resistor R11 and the bypass circuit of the transistor Q1, so that the charging of the cell is eased.
[0011]
The overcharge detection circuits 31 to 3n include a comparator C2, an inverter INV2, and resistors R25 and R26. The comparator C2 compares the threshold voltage Vc2 obtained by dividing the control power supply voltage Vcc with the resistors R25 and R26 with the cell voltage.
[Expression 2]
Vc2 = R26 / (R25 + R26) · Vcc
When the cell voltage exceeds the threshold value Vc2, the output of the comparator C2 becomes low level, is inverted to high level by the inverter INV2, and is output as an overcharge detection signal.
[0012]
The overdischarge detection circuits 41 to 4n include a comparator C3 and resistors R35 and R36. The comparator C3 compares the threshold voltage Vc1 obtained by dividing the control power supply voltage Vcc by the resistors R35 and R36 with the cell voltage.
[Equation 3]
Vc1 = R36 / (R35 + R36) ・ Vcc
When the cell voltage becomes lower than the threshold value Vc1, the output of the comparator C3 becomes high level and is output as an overdischarge detection signal.
[0013]
Returning to FIG. 1 again, the explanation will be continued. The outputs of the overcharge detection circuits 31 to 3n are connected to the OR element 5, and if any of the overcharge detection circuits 31 to 3n detects the overcharge state of the cell, the high level overcharge detection signal is ORed. It is sent from the element 5 to the charge / discharge control circuit 7. Further, the outputs of the overdischarge detection circuits 41 to 4n are connected to the OR element 6, and when a cell overdischarge state is detected by any of the overdischarge detection circuits 41 to 4n, a high level overdischarge detection signal is detected. Is sent from the OR element 6 to the charge / discharge control circuit 7.
[0014]
The charge / discharge control circuit 7 is composed of peripheral components such as a CPU, a ROM, a RAM, an A / D converter, etc., and controls the charge / discharge of the assembled battery 1 by executing a control program to be described later, and performs overdischarge and overcharge. Monitor.
[0015]
The voltage sensor 8 detects the voltage across the assembled battery 1 (hereinafter referred to as the total voltage) Vt, and outputs the detected total voltage Vt to the charge / discharge control circuit 7. The charge / discharge control circuit 7 measures the state of charge SOC for the total voltage Vt of the assembled battery 1, stores it as an SOC data map, and calculates the state of charge SOC of the assembled battery 1 corresponding to the measured total voltage Vt. To do.
[0016]
In this embodiment, the voltage sensor 8 detects the total voltage Vt of the assembled battery 1 and the charge / discharge control circuit 7 calculates the state of charge SOC of the assembled battery 1 based on the total voltage Vt. An SOC detection device may be provided instead of the sensor 8, and the SOC of the assembled battery 1 detected by the SOC detection device may be output to the charge / discharge control circuit 7.
[0017]
FIG. 3 shows the overdischarge threshold value and the overcharge threshold value of the state of charge SOC of the cell and the assembled battery. In this embodiment, the overdischarge threshold value and the overcharge threshold value of the state of charge SOC are set for the cells 11 to 1n and the assembled battery 1 as shown in FIG. Here, the overdischarge threshold is an SOC at which discharge should be stopped in order to prevent damage to the assembled battery 1 and the cells 11 to 1n. The overcharge threshold is an SOC that should be stopped to prevent damage to the assembled battery 1 and the cells 11 to 1n. An overdischarge threshold SOCc1 [%] and an overcharge threshold SOCc2 [%] are set for the cells 11 to 1n. For the battery pack 1, an overdischarge threshold SOCt1 [%] and an overcharge threshold SOCt2 [%] are set. It is desirable that SOCc1 <SOCt1 and SOCc2> SOCt2.
[0018]
In a normal use state of the assembled battery, the cell voltage has a strong correlation with the amount of charge of the cell, that is, the state of charge SOC, and the total voltage of the assembled battery has a strong correlation with the amount of charge of the assembled battery, that is, the state of charge SOC. In this embodiment, the cell voltage and the total voltage are used to monitor overcharge / discharge of the cells 11 to 1n and the assembled battery 1.
[0019]
The cell voltage Vc1 corresponding to the overdischarge threshold SOCc1 of the cells 11 to 1n and the cell voltage Vc2 corresponding to the overcharge threshold SOCc2 are measured, and an overdischarge detection circuit is obtained from the cell voltage Vc1 of the overdischarge threshold. The resistance values of the resistors R35 and R36 of 41 to 4n are determined, and the resistance values of the resistors R25 and R26 of the overcharge detection circuits 31 to 3n are determined by the cell voltage Vc2 of the overcharge threshold.
[0020]
Further, the total voltage Vt1 corresponding to the overdischarge threshold SOCt1 of the assembled battery 1 and the total voltage Vt2 corresponding to the overcharge threshold SOCt2 are measured and stored in the charge / discharge control circuit 7.
[0021]
FIG. 4 shows the configuration of a parallel hybrid vehicle equipped with the assembled battery 1 shown in FIG. 1 and its overcharge / discharge monitoring device. The overcharge / discharge monitoring device for an assembled battery according to the present invention is not limited to a parallel hybrid vehicle, and can be applied to any device using an assembled battery such as a series hybrid vehicle or an electric vehicle.
[0022]
In the parallel hybrid vehicle according to the embodiment, the rotating shaft of the AC motor 102 is directly connected to the output shaft of the engine 101, and the vehicle travels by the braking / driving force of one or both of the engine 101 and the motor 102. The braking / driving force of the engine 101 and / or the motor 102 is transmitted to the drive wheels 105a and 105b via the transmission 103 and the speed reducer 104.
[0023]
The assembled battery 1 supplies driving power to the motor 102 via the inverter 106 and receives regenerative power from the motor 102 via the inverter 106. The vehicle controller 107 controls the engine 101 and the inverter 106. The switch 108 performs disconnection and connection between the assembled battery 1 and the inverter 106.
[0024]
FIG. 5 is a flowchart showing an overcharge / discharge monitoring program executed by the charge / discharge control circuit 7. The operation of the first embodiment will be described with reference to this flowchart. In step 1, it is confirmed whether or not an overdischarge state is detected in any cell in the assembled battery 1. If an overdischarge is detected in any cell, the process proceeds to step 2, and if no overdischarge is detected. Proceed to step 5.
[0025]
If an overdischarge state is detected in any cell, a discharge inhibition signal is output to the vehicle controller 7 in step 2. When receiving the discharge inhibition signal, the vehicle controller 7 controls the inverter 106 to stop the discharge from the assembled battery 1 to the motor 102.
[0026]
In step 3, it is determined whether or not the total voltage Vt of the assembled battery 1 is greater than the overdischarge threshold value Vt1. If the total battery voltage Vt is equal to or lower than the overdischarge threshold value Vt1 when an overdischarge state of any cell is detected, all cells other than the cell in which the overdischarge state is detected are equally overdischarged. The battery pack 1 is not in failure or abnormal. Therefore, in this case, only discharging is prohibited and the process returns to step 1 to repeat the above-described processing. As a result, when an overdischarge state is detected in one of the cells when the assembled battery 1 is in a state close to overdischarge, it is determined that the assembled battery 1 is faulty or abnormal, and the vehicle is prohibited from traveling. Can be avoided.
[0027]
On the other hand, if the total battery voltage Vt is larger than the overdischarge threshold Vt1 when an overdischarge state of any cell is detected, cells other than the cell in which the overdischarge state is detected are in a normal state. In addition, since only the cells in which the overdischarge state is detected protrude and are in the overdischarge state, the assembled battery 1 is faulty or abnormal. Therefore, in this case, the process proceeds to step 4 and an abnormality signal is output to the vehicle controller 107. When the vehicle controller 107 receives the abnormality signal of the assembled battery 1, the vehicle controller 107 opens the switch 108 to shut off the assembled battery 1 and the inverter 106. Thereby, it is possible to continue to use the assembled battery 1 in which a failure or abnormality has occurred and further promote the failure or abnormality, thereby avoiding a situation where the vehicle is difficult to travel.
[0028]
If no cell overdischarge is detected in step 1, the process proceeds to step 5 to check whether an overcharged state is detected in any cell of the assembled battery 1, and if any cell overcharge is detected. Proceed to step 6, and if no overcharge is detected, proceed to step 9.
[0029]
If an overcharge state is detected in any of the cells, a charge prohibition signal is output to the vehicle controller 107 in step 6. When the vehicle controller 107 receives this charge prohibition signal, the vehicle controller 107 controls the inverter 106 to stop the charging from the motor 102 to the assembled battery 1.
[0030]
In step 7, it is determined whether the assembled battery total voltage Vt is smaller than the overcharge threshold Vt2. If the assembled battery total voltage Vt is equal to or higher than the overcharge threshold Vt2 when the overcharge state of any cell is detected, all cells other than the cell in which the overcharge state is detected are equally overcharged. The battery pack 1 is not in failure or abnormal. Therefore, in this case, only charging is prohibited and the process returns to step 1 to repeat the above-described processing. As a result, when the assembled battery 1 is in a state close to overcharging, an overcharged state is detected in one of the cells. Can be avoided.
[0031]
On the other hand, if the assembled battery total voltage Vt is smaller than the overcharge threshold Vt2 when the overcharge state of any cell is detected, the cells other than the cell in which the overcharge state is detected are in a normal state. Thus, only the cell in which the overcharged state is detected protrudes and is in the overcharged state. Accordingly, in this case, the process proceeds to step 8 and an abnormality signal is output to the vehicle controller 107. When the vehicle controller 107 receives the abnormality signal of the assembled battery 1, the vehicle controller 107 opens the switch 108 to shut off the assembled battery 1 and the inverter 106. Thereby, it is possible to continue to use the assembled battery 1 in which a failure or abnormality has occurred and further promote the failure or abnormality, thereby avoiding a situation where the vehicle is difficult to travel.
[0032]
When the overdischarge state and the overcharge state are not detected in all the cells 11 to 1n, it is determined in step 9 whether or not the assembled battery total voltage Vt is smaller than the overdischarge threshold value Vt1. When the assembled battery total voltage Vt is smaller than the overdischarge threshold value Vt1, the process proceeds to step 10 to output a discharge limit signal to the vehicle controller 107. Upon receiving this discharge restriction signal, the vehicle controller 107 controls the inverter 106 to limit the amount of discharge from the assembled battery 1 to the motor 102. Thereby, it can prevent beforehand that the assembled battery 1 will be in an overdischarge state.
[0033]
On the other hand, if the assembled battery total voltage Vt is equal to or higher than the overdischarge threshold Vt1, the process proceeds to step 11 to determine whether or not the assembled battery total voltage Vt is larger than the overcharge threshold Vt2. When the assembled battery total voltage Vt is larger than the overcharge threshold Vt2, the process proceeds to step 12 and a charge limit signal is output to the vehicle controller 107. When the vehicle controller 107 receives this charge restriction signal, the vehicle controller 107 controls the inverter 106 to restrict the amount of charge from the motor 102 to the assembled battery 1. Thereby, it can prevent beforehand that the assembled battery 1 will be in an overcharge state.
[0034]
When the total battery voltage Vt is in the range of the overdischarge threshold Vt1 or more and the overcharge threshold Vt2 or less, both the battery pack 1 and the cells 11 to 1n are in a normal state, and the process returns to step 1. The above process is repeated.
[0035]
As described above, according to the first embodiment, when an overdischarge state of an assembled battery is detected when an overdischarge state of any of the cells constituting the assembled battery is detected, the assembled battery is abnormal. Since no signal was output and a discharge prohibition signal was output, an overdischarge condition was detected in one of the cells when the assembled battery was in a state close to overdischarge. It is possible to avoid a situation where the vehicle is judged to be abnormal and the vehicle is prohibited from traveling. In addition, when the overdischarge state of any of the cells constituting the assembled battery is detected, if the overdischarged state of the assembled battery is not detected, the assembled battery abnormal signal is output. By continuing to use the assembled battery in which an abnormality has occurred, the failure or abnormality can be further promoted, and the situation where the vehicle is difficult to travel can be avoided.
[0036]
Further, according to the first embodiment, when an overcharged state of any one of the cells constituting the assembled battery is detected, if the overcharged state of the assembled battery is detected, the assembled battery abnormality signal is generated. Since the charging prohibition signal is output instead of outputting, an overcharged state is detected in one of the cells when the assembled battery is in a state close to overcharging. It is possible to avoid such a situation that the determination and the travel of the vehicle are prohibited. In addition, when an overcharged state of any of the cells constituting the assembled battery is detected, if an overcharged state of the assembled battery is not detected, an assembled battery abnormality signal is output. By continuing to use the assembled battery in which an abnormality has occurred, the failure or abnormality can be further promoted, and the situation where the vehicle is difficult to travel can be avoided.
[0037]
As described above, according to the first embodiment, it is possible to enhance the contents of monitoring, and it is possible to take an optimum response as a vehicle system.
[0038]
<< Second Embodiment of the Invention >>
In 1st Embodiment mentioned above, the example which can distinguish whether any cell of the assembled battery 1 was in an overdischarge state, or was in an overcharge state was shown. A second embodiment will be described in which a cell is not distinguished and detected whether it is in an overdischarged state or an overcharged state.
[0039]
FIG. 6 shows the configuration of the second embodiment. In addition, the same code | symbol is attached | subjected with respect to the apparatus similar to the apparatus shown in FIG. 1, and it demonstrates centering around difference. In the second embodiment, the overcharge detection circuit output and the overdischarge detection circuit output for each cell are connected to an OR element provided for each cell. For example, in the cell 11, the output of the overcharge detection circuit 31 and the output of the overdischarge detection circuit 41 are both connected to the OR element 51. Similarly, in cell 1n, the output of overcharge detection circuit 3n and the output of overdischarge detection circuit 4n are both connected to OR element 5n. The outputs of these OR elements 51 to 5n are connected to the OR element 6, and the outputs of the OR element 6 are connected to the charge / discharge control circuit 7. Therefore, in the second embodiment, it is only detected that any cell in the assembled battery 1 is in an overcharge / discharge state, and the cell in the overcharge / discharge state is identified. There is no distinction between being charged or overdischarged.
[0040]
The current bypass circuits 21 to 2n, overcharge detection circuits 31 to 3n, and overdischarge detection circuits 41 to 4n of the second embodiment are the same as the circuit of the first embodiment shown in FIG. In addition, the overdischarge threshold values SOCc1, Vc1, overcharge threshold values SOCc2, Vc2 of the cells 11 to 1n of the second embodiment, the overdischarge threshold values SOCt1, Vt1, the overcharge threshold value of the assembled battery 1 SOCt2 and Vt2 are the same as the threshold values of the first embodiment shown in FIG. Furthermore, the configuration of the parallel hybrid vehicle equipped with the assembled battery 1 and the overcharge / discharge monitoring device of the second embodiment is the same as the configuration of the first embodiment shown in FIG.
[0041]
FIG. 7 is a flowchart showing an overcharge / discharge control program executed by the charge / discharge control circuit 7. The operation of the second embodiment will be described with reference to this flowchart. In step 21, it is confirmed whether any of the overcharge state or the overdischarge state is detected in any cell in the assembled battery 1, and if any overcharge / discharge detection is detected in any cell, go to step 22. If no overcharge / discharge detection is detected, the process proceeds to step 25.
[0042]
If any of the overcharged state and the overdischarged state is detected in any of the cells, a charge / discharge inhibition signal is output to the vehicle controller 107 in step 22. Upon receiving this overcharge / discharge prohibition signal, the vehicle controller 107 controls the inverter 106 to stop discharging from the assembled battery 1 to the motor 102 and charging from the motor 102 to the assembled battery 1.
[0043]
In step 23, whether or not the total voltage Vt of the assembled battery 1 is not less than the overdischarge threshold Vt1 and not more than the overcharge threshold Vt2, that is, the assembled battery 1 is in a normal state capable of being charged and discharged. It is determined whether or not there is. When any of the overcharged state and the overdischarged state is detected in any cell, the assembled battery total voltage Vt is in the range of the overdischarge threshold Vt1 or more and the overcharge threshold Vt2 or less, If the assembled battery 1 is in a normal state that can be charged / discharged, cells other than the cell in which the overcharge / discharge state is detected are in a normal state, and only the cell in which the overcharge / discharge state is detected protrudes and overdischarges. Or since it is in an overcharge state, it is a failure or abnormality of the assembled battery 1. Accordingly, in this case, the process proceeds to step 24 and an abnormal signal is output to the vehicle controller 107. When the vehicle controller 107 receives the abnormality signal of the assembled battery 1, the vehicle controller 107 opens the switch 108 to shut off the assembled battery 1 and the inverter 106. Thereby, it is possible to continue to use the assembled battery 1 in which a failure or abnormality has occurred and further promote the failure or abnormality, thereby avoiding a situation where the vehicle is difficult to travel.
[0044]
On the other hand, when either the overcharge state or the overdischarge state is detected in any cell, the assembled battery total voltage Vt is not less than the overdischarge threshold value Vt1 and not more than the overcharge threshold value Vt2. In other words, that is, when the assembled battery 1 is not in a normal state capable of being charged / discharged, it is considered that all cells other than the cells in which the overcharge / discharge state is detected are equally in an overcharge or overdischarge state, It cannot be said that the battery pack 1 is broken or abnormal. Therefore, in this case, charging / discharging is prohibited and the process returns to step 21 to repeat the above-described processing. Thereby, when the assembled battery 1 is not in a normal state that can be charged / discharged, it is determined that an overcharge or overdischarge state has been detected in any cell, and the vehicle is determined as a failure or abnormality of the assembled battery 1. It is possible to avoid a situation that prohibits running.
[0045]
If no overcharge / discharge detection of the cell is detected in step 21, the process proceeds to step 25, and it is determined whether or not the assembled battery total voltage Vt is smaller than the overdischarge threshold Vt1. When the assembled battery total voltage Vt is smaller than the overdischarge threshold Vt1, the process proceeds to step 26, and a discharge limit signal is output to the vehicle controller 107. Upon receiving this discharge restriction signal, the vehicle controller 107 controls the inverter 106 to limit the amount of discharge from the assembled battery 1 to the motor 102. Thereby, it can prevent beforehand that the assembled battery 1 will be in an overdischarge state.
[0046]
Further, when the assembled battery total voltage Vt is equal to or higher than the overdischarge threshold Vt1, the process proceeds to step 27, and it is determined whether or not the assembled battery total voltage Vt is larger than the overcharge threshold Vt2. When the assembled battery total voltage Vt is larger than the overcharge threshold Vt2, the process proceeds to step 28, and a charge limit signal is output to the vehicle controller 107. When the vehicle controller 107 receives this charge restriction signal, the vehicle controller 107 controls the inverter 106 to restrict the amount of charge from the motor 102 to the assembled battery 1. Thereby, it can prevent beforehand that the assembled battery 1 will be in an overcharge state.
[0047]
When the assembled battery total voltage Vt is not less than the overdischarge threshold value Vt1 and not more than the overcharge threshold value Vt2, both the assembled battery 1 and the cells 11 to 1n are in a normal state, and the process returns to step 21. The above processing is repeated.
[0048]
As described above, when an overcharged state or an overdischarged state of any of the cells constituting the assembled battery is detected, if a normal state where the assembled battery is chargeable / dischargeable is not detected, an assembled battery abnormality signal is output. Since the charge / discharge prohibition signal is output, the overcharge or overdischarge state is detected in any cell when the assembled battery is not in a normal state where charge / discharge is possible. It is possible to avoid a situation in which it is determined that the battery is malfunctioning or abnormal and prohibits traveling of the vehicle. In addition, when an overcharged state or an overdischarged state of any of the cells constituting the assembled battery is detected, if a normal state in which the assembled battery can be charged / discharged is detected, an assembled battery abnormality signal is output. Since it did in this way, it can continue using the assembled battery in which the failure or abnormality generate | occur | produces, can further promote a failure or abnormality, and can avoid the situation where driving | running | working of a vehicle becomes difficult.
[0049]
As described above, according to the second embodiment, it is possible to enhance the contents of monitoring, and it is possible to take an optimum response as a system.
[0050]
The correspondence between the constituent elements of the claims and the constituent elements of the embodiment is as follows. That is, the voltage sensor 8 and the charge / discharge control circuit 7 are the battery overdischarge detection means, the battery overcharge detection means and the battery state electricity detection means, the overdischarge detection circuits 41 to 4n are the cell overdischarge detection means, and the overcharge detection circuit. Reference numerals 31 to 3n constitute cell overcharge detection means, and overdischarge detection circuits 41 to 4n and overcharge detection circuits 31 to 3n constitute cell overcharge / discharge detection means. In addition, as long as the characteristic function of this invention is not impaired, each component is not limited to the said structure.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of an overcharge / discharge monitoring apparatus for a battery pack according to a first embodiment.
FIG. 2 is a detailed circuit diagram of a current bypass circuit, an overcharge detection circuit, and an overdischarge detection circuit.
FIG. 3 is a diagram showing an overdischarge threshold value and an overcharge threshold value of a state of charge SOC of a cell and an assembled battery.
FIG. 4 is a diagram showing a configuration of a parallel hybrid vehicle equipped with the assembled battery and the overcharge / discharge monitoring device of the first embodiment.
FIG. 5 is a flowchart showing an overcharge / discharge monitoring program according to the first embodiment;
FIG. 6 is a diagram showing a configuration of an overcharge / discharge monitoring apparatus for an assembled battery according to a second embodiment.
FIG. 7 is a flowchart showing an overcharge / discharge monitoring program according to the second embodiment;
[Explanation of symbols]
1 assembled battery 5, 51 to 5n, 6 OR element 7 charge / discharge control circuit 8 voltage sensor 11 to 1n cell 21 to 2n current bypass circuit 31 to 3n overcharge detection circuit 41 to 4n overdischarge detection circuit 101 engine 102 motor 103 speed change Speed reducer 105a, 105b Drive wheel 106 Inverter 107 Vehicle controller 108 Switch

Claims (6)

A device for monitoring an overdischarge state of a battery pack in which a plurality of unit cells (hereinafter referred to as cells) are connected in series, or a battery pack in which a plurality of cell parallel circuits in which a plurality of cells are connected in parallel are connected in series. ,
Battery overdischarge detection means for detecting an overdischarge state of the assembled battery;
Cell overdischarge detection means for detecting an overdischarge state of any one of the cells constituting the assembled battery or the cell parallel circuit;
If an overdischarge state of the assembled battery is detected when an overdischarge state of any of the cells constituting the assembled battery or the cell parallel circuit is detected , charging / discharging of the assembled battery is performed by a switch. An overdischarge monitoring device for an assembled battery, which outputs a discharge inhibition signal without outputting an assembled battery abnormality signal for blocking a path . The overdischarge monitoring device for an assembled battery according to claim 1,
When over-discharge state of either the cell or the cell parallel circuit constituting the battery pack is detected, if the over-discharge state of the battery pack is not detected, it outputs the battery pack abnormality signal An overdischarge monitoring device for an assembled battery. The overdischarge monitoring device for an assembled battery according to claim 1 or 2,
An overdischarge monitoring of the assembled battery, wherein an overdischarge state of the assembled battery is detected when an overdischarge state of the cell or the cell parallel circuit is not detected, and a discharge limit signal is output. apparatus. An apparatus for monitoring an overcharged state of an assembled battery in which a plurality of unit cells (hereinafter referred to as cells) are connected in series, or a plurality of cell parallel circuits in which a plurality of cells are connected in parallel. ,
Battery overcharge detection means for detecting an overcharge state of the assembled battery;
Cell overcharge detection means for detecting an overcharge state of any of the cells or the cell parallel circuit constituting the assembled battery,
When an overcharge state of the assembled battery is detected when an overcharge state of any one of the cells constituting the assembled battery or the cell parallel circuit is detected , charging / discharging of the assembled battery is performed by a switch. An overcharge monitoring device for an assembled battery, which outputs a charge prohibition signal without outputting an assembled battery abnormality signal for blocking a path . The overcharge monitoring device for an assembled battery according to claim 4,
When overcharge state of either the cell or the cell parallel circuit constituting the battery pack is detected, if the overcharge state of the battery pack is not detected, it outputs the battery pack abnormality signal An overcharge monitoring device for an assembled battery. In the overcharge monitoring device for an assembled battery according to claim 4 or 5,
When an overcharge state of the battery pack is detected when an overcharge state of the cell or the cell parallel circuit is not detected, a charge limit signal is output, and the overcharge monitoring of the battery pack is characterized in that apparatus.

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