JP2021141701A - Battery monitoring device - Google Patents

Abstract

To provide a technique capable of grasping a change of battery characteristic and a change of full charge capacity.SOLUTION: In a battery monitoring device 1, a battery monitoring device 101 has a determining unit 111 determining whether a first charge duration is less than a charge possible time, and a charge unit 112, when the determination of the determining unit 111 is satisfied, performing first charge for charging by repeatedly charging specified quantity and leaving for a prescribed time, and obtaining an amount of charge and battery voltage associated with each other at the time of leaving completion.SELECTED DRAWING: Figure 1

Description

The present invention relates to a battery monitoring device.

It is known that the charge / discharge amount Ah-OCV (Open Circuit Voltage) characteristic of a battery changes with aging and the like. In such a battery monitoring device, there is a device that calculates the SOC-OCV curve by accumulating the OCV estimated from the CCV (Closed Circuit Voltage) and the SOC (State Of Charge) estimated by the current integration. For example, see Patent Document 1.

JP-A-2017-223536

However, it is difficult to estimate the SOC or SOC-OCV curve based on the conventional technique. In particular, in order to acquire the charge / discharge amount Ah-OCV characteristic, it is necessary to charge / discharge little by little and wait for the polarization to be eliminated each time, so that it cannot be carried out during normal charging / discharging.

An object of one aspect of the present invention is to provide a battery monitoring device capable of grasping changes in battery characteristics.

The battery monitoring device according to one aspect of the present invention has a determination unit for determining whether the first charging time is less than the rechargeable time, and if the determination is satisfied, the battery is repeatedly charged by a predetermined amount and left for a predetermined time. It is characterized by including a charging unit that performs a first charging that charges and acquires the charge amount and the battery voltage in association with each other when the battery is left unattended.

Therefore, if there is sufficient time required for charging, the battery is charged by repeating charging a predetermined amount little by little and leaving it for a predetermined time, and at the end of leaving, the charged amount and the battery voltage after polarization elimination are acquired. .. As a result, it is possible to acquire the charge amount Ah-OCV characteristic after deterioration, and it is possible to grasp the change in the battery characteristic after deterioration.

Further, the determination unit determines whether the second charging time is less than the chargeable time, and the charging unit determines whether the second charging time is less than the chargeable time, and when the determination is satisfied, the second charging time is less than the chargeable time. Is characterized in that after discharging to SOC 0%, charging is performed while repeating charging a predetermined amount and leaving the battery for a predetermined time, and at the end of leaving the battery, a second charge is performed in which the charge amount and the battery voltage are acquired in association with each other. ..

Therefore, if there is sufficient time required for charging, the battery is discharged until the SOC reaches 0% before charging. After that, the battery is charged by repeating charging a predetermined amount little by little and leaving it for a predetermined time, and at the end of leaving the battery, the charged amount and the battery voltage after the polarization is eliminated are acquired. As a result, it is possible to accurately acquire the charge amount Ah-OCV characteristic after deterioration without being affected by the charge amount Ah-OCV characteristic before deterioration, and to accurately grasp the change in the battery characteristic after deterioration. Can be done.

Further, the determination unit determines whether the third charge time required is less than the chargeable time, and when the third charge time is less than the chargeable time, the charging unit determines the amount of the first amount. Discharge while repeating discharging and leaving for the first time, obtain the discharge amount and battery voltage in association with each other, discharge to SOC 0%, and then charge the second amount and leave for the second time. It is characterized in that the battery is repeatedly charged, and at the end of leaving the battery, a third charge is performed in which the charge amount and the battery voltage are acquired in association with each other.

Therefore, if there is sufficient time required for charging, the battery is discharged while repeating a predetermined amount of discharge and leaving for a predetermined time little by little, and at the end of leaving, the discharge amount and the battery voltage after depolarization are acquired. Therefore, it is possible to acquire the charge amount Ah-OCV characteristic after deterioration.

Further, after discharging until the SOC reaches 0%, the battery is charged by repeating charging a predetermined amount little by little and leaving the battery for a predetermined time, and at the end of leaving the battery, the charged amount and the battery voltage after polarization is eliminated, thereby deteriorating. The later charge amount Ah-OCV characteristic can be acquired. As a result, by acquiring the charge / discharge amount and the battery voltage after polarization elimination acquired during charging and discharging, charging after deterioration is performed with approximately twice the accuracy as compared with the case where it is acquired only during charging or discharging. The quantity Ah-OCV characteristic can be obtained.

The battery monitoring device according to one aspect of the present invention includes a storage unit that stores the correlation between the battery charge amount and the OCV, a determination unit that determines whether or not a user operation has been accepted, and a predetermined amount if the determination is satisfied. Based on the charging unit that performs the first charging, which charges the battery while repeating charging and leaving the battery for a predetermined time, and acquires the charge amount and the battery voltage in association with each other at the end of the neglect, and each of the acquired charge amounts and the battery voltage. It is characterized by including an update unit that updates the correlation of the storage unit.

Therefore, when an explicit instruction is received from the user, the battery is charged by repeating charging a predetermined amount little by little and leaving it for a predetermined time, and at the end of leaving, the charge amount and the battery voltage after polarization elimination are acquired. , The charge amount Ah-OCV characteristic after deterioration can be acquired. Thereby, the change in the battery characteristics can be grasped at the timing desired by the user. Then, the correlation between the battery charge amount stored in the storage unit and the OCV can be updated based on the acquired charge amount and the battery voltage after the polarization is eliminated. This makes it possible to grasp changes in battery characteristics.

According to the present invention, changes in battery characteristics and changes in full charge capacity can be grasped.

It is a figure which shows the use example of the battery pack including the battery monitoring device which concerns on 1st Embodiment. It is a figure which shows an example which acquires the charge amount and the battery voltage in association with each other. It is a figure which shows the correlation about charge / discharge amount of a secondary battery and OCV. It is a flowchart which shows an example of the process of the 1st charge of 1st Embodiment. It is a flowchart which shows an example of the process of the 2nd charge of 2nd Embodiment. It is a flowchart which shows an example of the process of the 3rd charge of 3rd Embodiment. It is a flowchart which shows an example of the process of 1st charge of 4th Embodiment.

<First Embodiment>
FIG. 1 is a diagram showing a usage example of the battery pack 100 including the battery monitoring device according to the first embodiment. In this embodiment, the battery pack 100 is used in an electric vehicle 1 such as an electric vehicle or a plug-in hybrid vehicle, and is used for battery monitoring to calculate the full charge capacity of the secondary battery 102 for supplying a current to the traveling motor 11. The device (battery ECU (Electronic Control Unit)) 101 is included.

The battery pack 100 includes a battery monitoring device (battery ECU) 101, a secondary battery 102, a monitoring ECU 103, a current sensor 104, a thermistor 105, relays 106, and 107. The battery pack 100 may have other circuit configurations not shown in FIG.

The secondary battery 102 is realized by an assembled battery including a plurality of battery modules connected in series. Then, the monitoring ECU 103 measures the voltage of the secondary battery 102 and also measures the voltage of each battery module constituting the secondary battery 102. Further, each battery module is composed of, for example, a plurality of battery cells connected in series. In this case, the monitoring ECU 103 may measure the voltage of each battery cell. The monitoring ECU 103 functions as a sensor for measuring the voltage of the battery cell of the secondary battery 102. In the following description, each battery module or each battery cell may be simply referred to as a "battery".

The current sensor 104 is composed of, for example, a Hall element or a shunt resistor, and detects the current flowing through the secondary battery 102, the relays 106, and 107. The current sensor 104 functions as a sensor that detects the current flowing through the secondary battery 102. The thermistor 105 detects the battery temperature of the secondary battery 102 or the ambient temperature of the secondary battery 102. The thermistor 105 functions as a sensor for measuring the battery temperature of the secondary battery 102. The monitoring ECU 103 sends the battery status information indicating the voltage of the secondary battery 102, the current detected by the current sensor 104, and the temperature detected by the thermistor 105 to the battery monitoring device 101.

The charger 21 charges the secondary battery 102. At this time, the charger 21 may charge the secondary battery 102 based on the voltage monitored by the monitoring ECU 103 and the current monitored by the current sensor 104. The secondary battery 102 can be charged by the charger 21 by, for example, constant current charging (CC (Constant Current) charging) or constant current constant voltage charging (CCCV (Constant Current Constant Voltage) charging). When the electric vehicle 1 is traveling, a current is supplied from the secondary battery 102 to the traveling motor 11. At this time, the inverter circuit 12 converts the DC power of the secondary battery 102 into AC power and outputs it to the traveling motor 11. Further, at the time of regeneration, the inverter circuit 12 converts the AC power of the traveling motor 11 into DC power and outputs it to the secondary battery 102.

A relay 106 is provided between the secondary battery 102 and the charger 21. Further, on the negative electrode side of the secondary battery 102, a relay 107 is provided between the secondary battery 102, the traveling motor 11, and the charger 21. Then, the battery monitoring device 101 controls the relays 106 and 107. For example, when the charger 21 charges the secondary battery 102, the battery monitoring device 101 controls the relays 106 and 107 to be in the ON state. When the secondary battery 102 is in the overcharged state, the battery monitoring device 101 may control the relays 106 and 107 to be in the off state. When the electric vehicle 1 is traveling, the battery monitoring device 101 controls the relay 107 to be in the ON state. When the secondary battery 102 is in the over-discharged state, the battery monitoring device 101 may control the relays 106 and 107 to be in the off state.

The battery monitoring device 101 includes, for example, a CPU (Central Processing Unit), a multi-core CPU, and a programmable device (FPGA (Field Programmable Gate).
A circuit using Array) or PLD (Programmable Logic Device) can be considered. Further, the battery monitoring device 101 includes a storage unit 110 provided inside or outside, and reads and executes a program for controlling each part of the battery pack 100 stored in the storage unit 110. Further, the storage unit 110 stores the correlation between the charge amount Ah or the discharge amount Ah of the secondary battery 102 and the OCV. In this embodiment, the battery monitoring device 101 will be used for explanation, but the control executed by the battery monitoring device 101 may be performed by, for example, one or more ECUs mounted on the electric vehicle 1. ..

The battery monitoring device 101 determines the limited output power (Wout) information and regenerative power (Win) information based on the upper and lower thresholds of the SOC (State Of Charge) of the secondary battery 102. .. When the SOC of the secondary battery 102 is below the lower limit threshold, the limited output power (Wout) information is transmitted to the vehicle ECU 13, and when the SOC of the secondary battery 102 is above the upper limit threshold, the limited regenerative power (Wout) ( Win) Information is transmitted to the vehicle ECU 13.

The vehicle ECU 13 limits the output from the secondary battery 102 to the traveling motor 11 according to the output power (Wout) information from the battery monitoring device 101. Further, the vehicle ECU 13 limits the regeneration from the traveling motor 11 to the secondary battery 102 according to the regenerative electric energy (Win) information from the battery monitoring device 101. Specifically, the vehicle ECU 13 limits the output power of the inverter circuit 12 based on the output power (Wout) information based on the SOC of the secondary battery 102, and limits the output of the traveling motor 11. Further, the vehicle ECU 13 limits the output power of the inverter circuit 12 based on the regenerative power (Win) information based on the SOC of the secondary battery 102, and limits the regeneration from the traveling motor 11.

The method for limiting the output power of the inverter circuit 12 is not particularly limited because a known method can be adopted. For example, as an example of the method of controlling the output power, the vehicle ECU 13 can adopt a method of lowering the duty ratio by changing the switching frequency of the switches constituting the inverter circuit 12.

The battery monitoring device 101 determines the output power (Wout) information and the regenerative power (Win) information based on the SOC of the secondary battery 102, but this is not the case. For example, the battery monitoring device 101 may determine the limited output power (Wout) information and regenerative power (Win) information based on the upper limit threshold value and the lower limit threshold value of the voltage of the secondary battery 102. When the voltage of the secondary battery 102 is below the lower limit threshold, the limited output power (Wout) information is transmitted to the vehicle ECU 13, and when the voltage of the secondary battery 102 is above the upper limit threshold, the limited regenerative power (Wout) ( Win) Information is transmitted to the vehicle ECU 13.

In this case, the vehicle ECU 13 limits the output from the secondary battery 102 to the traveling motor 11 according to the output power (Wout) information based on the voltage of the secondary battery 102. Further, the vehicle ECU 13 limits the regeneration from the traveling motor 11 to the secondary battery 102 according to the regenerative electric energy (Win) information based on the voltage of the secondary battery 102.

The vehicle ECU 13 may give a current command value to the charger 21 based on the output power (Wout) information and the regenerative power (Win) information of the secondary battery 102 received from the battery monitoring device 101. Further, the vehicle ECU 13 can give a control signal to the battery monitoring device 101 as needed. The battery monitoring device 101 and the vehicle ECU 13 may be connected to each other so as to be able to communicate with each other by CAN (Controller Area Network) communication.

Here, the battery monitoring device 101 of this embodiment includes a storage unit 110, a determination unit 111, a charging unit 112, and an updating unit 113. The battery monitoring device 101 may have other circuit configurations not shown in FIG.

The determination unit 111 determines whether the first charging time is less than the chargeable time.

The first charging time is the charging time required when the secondary battery 102 is intermittently charged while repeatedly charging a predetermined amount and leaving it for a predetermined time. The chargeable time refers to the time until the charge completion reservation time or the estimated time until the user next uses it. The charge completion reservation time refers to the charge completion time reserved based on the user's operation. The estimated time until the user next uses is the time estimated to use the electric vehicle 1 next based on the user's behavior pattern.

When the determination unit 111 determines that the first charging time is less than the chargeable time, the charging unit 112 charges the battery while repeating charging a predetermined amount and leaving the battery for a predetermined time, and at the end of leaving the battery, the charging amount Ah and the battery The first charge that acquires the voltage in association with each other is performed. The amount of charge to be acquired is not limited to Ah and may be SOC. If the SOC is not discharged to 0% before the start of charging, the charging unit 112 acquires the current charging / discharging amount Ah based on the charge / discharge amount Ah-OCV characteristic stored in the storage unit 110. Then, the charging unit 112 matches the charge / discharge amount of the charge / discharge Ah-OCV characteristic with the charge / discharge amount Ah at the start of charging based on the acquired charge / discharge amount Ah-OCV characteristic and the charge / discharge amount Ah at the start of charging. Let me. The charging unit 112 acquires the SOC-OCV based on the acquired charge / discharge amount Ah-OCV characteristic.

The predetermined amount of charging refers to charging performed intermittently by a predetermined amount of charge by CC charging or CCCV charging. The predetermined charge amount may be variable based on the chargeable time. When the rechargeable time is short, the charge amount per charge may be set long, and when the rechargeable time is long, the charge amount per charge may be set short. As a result, when there is a margin in the chargeable time, it is possible to acquire the highly accurate charge amount Ah and the battery voltage. Further, even when there is no margin in the chargeable time, it is possible to acquire the highly accurate charge amount Ah and the battery voltage according to the chargeable time.

The predetermined time required for leaving is the time required for eliminating the polarization of the secondary battery 102. The predetermined time required for leaving may be variable. For example, the charging unit 112 may consider the time when the voltage change per unit time becomes equal to or less than the threshold value as the polarization elimination time, and set it as a predetermined time required for leaving. Further, the charging unit 112 may set the polarization elimination time calculated from the SOC of the secondary battery 102, the battery temperature, and the charge amount as a predetermined time required for leaving. Further, the charging unit 112 may be set so that the required time gradually decreases with the elapsed time or the current integration during CV charging. Further, the charging unit 112 may set the required time variably according to the chargeable time.

The method for acquiring the first charge time is not particularly limited, but for example, the OCV of the current secondary battery 102 and the correlation between the charge amount Ah and the OCV stored in advance in the storage unit 110 can be determined. Based on this, it can be calculated based on the following equation (1) by acquiring the charge amount ΔAh1 required until the battery is fully charged.
(ΔAh1 ÷ e) × ((e ÷ A1) + t) ・ ・ ・ Equation (1)
However, e is a predetermined amount (charge amount) in intermittent charging, A1 is a charging current value, and t is a predetermined time in intermittently left unattended. As the charging current value A1, for example, when charging the secondary battery 102 by CC charging, the current value of the CC charging can be used, and when charging the secondary battery 102 by CCCV charging, the CCCV The average current value or the like from the start to the end of charging can be used.

FIG. 2 is a diagram showing an example of acquiring the charge amount Ah and the battery voltage in association with each other. As shown in FIG. 2, the charging unit 112 starts charging when the determination by the determination unit 111 is satisfied, starts leaving when the predetermined amount e is charged, and after being left for a predetermined time t. The charge amount Ah and the battery voltage v1 at that time are obtained in association with each other. After that, the charging unit 112 starts charging again, and when the predetermined amount e is charged, the charging unit 112 starts leaving the battery, and after being left for a predetermined time t, acquires the charged amount Ah and the battery voltage v2 at that time in association with each other. do. The charging unit 112 charges the battery while repeating charging the predetermined amount e and leaving the battery for a predetermined time t until the SOC reaches 100%, and at the end of leaving the battery, performs the first charging in which the charge amount Ah and the battery voltage are acquired in association with each other. .. As a result, it is possible to acquire the charge amount Ah-OCV characteristic after deterioration, and it is possible to grasp the change in the battery characteristic after deterioration.

Further, when the SOC reaches 100%, the fully charged capacity after deterioration can be calculated based on the integrated value of the charge amount after each leaving and the change amount of the SOC before and after charging. This makes it possible to grasp the change in battery characteristics after deterioration.

The update unit 113 updates the correlation between the charge amount Ah or the discharge amount Ah of the secondary battery 102 stored in the storage unit 110 and the OCV based on each charge amount and the battery voltage acquired by charging the charging unit 112. do.

FIG. 3 is a diagram showing a correlation C regarding the charge / discharge amount Ah and OCV of the secondary battery 102. In FIG. 3, as the correlation C, the correlation C1 regarding the charge / discharge amount Ah and OCV before the update and the correlation C2 regarding the charge / discharge amount Ah and the OCV after the update are displayed.

As shown in FIG. 3, the storage unit 110 stores the correlation C regarding the charge / discharge amount Ah-OCV characteristic previously stored in the storage unit 110. However, as the secondary battery 102 deteriorates, the charge / discharge amount Ah-OCV characteristics change and the full charge capacity decreases. Therefore, the update unit 113 correlates with the charge amount Ah or the discharge amount Ah of the secondary battery 102 stored in the storage unit 110 and the OCV based on each charge amount and the battery voltage acquired by charging the charging unit 112. Update C1 to correlation C2. This makes it possible to grasp the change in battery characteristics after deterioration.

FIG. 4 is a flowchart showing an example of the first charging process of the first embodiment.

The determination unit 111 determines whether the first charging time is less than the chargeable time (S11). When it is determined that the first charging required time is less than the rechargeable time (S11: YES), the charging unit 112 starts charging the secondary battery 102 (S12). The charging unit 112 charges until a predetermined amount of charging is performed, and when the predetermined amount of charging is performed (S13: YES), the charging unit 112 stops charging the secondary battery 102 and leaves it unattended. (S14). When the charging unit 112 is left for a predetermined time and left for a predetermined time (S15: YES), the charging amount and the battery voltage are acquired in association with each other after the leaving is completed (S16).

The charging unit 112 determines whether the SOC of the secondary battery 102 is 100%, and if the SOC is not 100% (S17: NO), the process returns to the process of S12. Then, until the SOC reaches 100%, the processes S12 to S17, in which the secondary battery 102 is intermittently charged while being repeatedly charged by a predetermined amount and left for a predetermined time, are repeatedly executed. When the SOC becomes 100% as a result of repeating the processes of S12 to S17 (S17: YES), the process of FIG. 4 ends.

If it is determined that the first charging time exceeds the chargeable time (S11: NO), the normal charging process is performed. That is, the charging unit 112 starts charging (S18). The charging unit 112 charges until the SOC reaches 100%, and when the SOC reaches 100% (S19: YES), the process of FIG. 4 ends.

Therefore, according to the first embodiment, when the time required for charging is sufficiently sufficient, the battery is charged by repeating charging a predetermined amount little by little and leaving it for a predetermined time, and at the end of leaving the battery, the charge amount is increased. Obtain the battery voltage after the polarization is eliminated. As a result, it is possible to acquire the charge amount Ah-OCV characteristic after deterioration, and it is possible to grasp the change in the battery characteristic after deterioration.

Further, when the SOC reaches 100%, the fully charged capacity after deterioration can be calculated based on the integrated value of the charge amount after each leaving and the change amount of the SOC before and after charging. This makes it possible to grasp the change in the full charge capacity after deterioration.

<Second embodiment>
Since the configuration of the battery monitoring device according to the second embodiment is substantially the same as the configuration of the first embodiment, the description thereof will be omitted with reference to FIG.

In the first embodiment, the determination unit 111 determines whether the first charging time is less than the chargeable time, whereas in the second embodiment, the second charge time is the chargeable time. It differs in that it determines whether it is below. The second charging time is the charging time required when the secondary battery 102 is completely discharged and then intermittently charged while being left for a predetermined time repeatedly. Therefore, the time required for the second charge is longer than the time required for the first charge.

Further, when the determination unit 111 determines that the first charging time is less than the rechargeable time, the charging unit 112 of the first embodiment charges the battery while repeating charging a predetermined amount and leaving the battery for a predetermined time. While the first charge is performed to acquire the charge amount Ah and the battery voltage in association with each other at the end of leaving the battery, in the second embodiment, when it is determined that the second charge time is less than the chargeable time, SOC0. The difference is that after discharging to%, charging is performed while repeating charging a predetermined amount and leaving the battery for a predetermined time, and at the end of leaving the battery, a second charge is performed in which the charged amount and the battery voltage are acquired in association with each other. The discharge of the secondary battery 102 to SOC 0% may be performed by the motor 11 and the inverter 12, or may be performed by a load (not shown).

The method for acquiring the second charging time is not particularly limited, but for example, the OCV of the current secondary battery 102, the correlation between the charge / discharge amount Ah and the OCV stored in advance in the storage unit 110, and the correlation. By acquiring the charge amount ΔAh1 required to reach full charge and the discharge amount ΔAh2 required to reach 0% SOC, it can be calculated based on the following equation (2).
(ΔAh2 ÷ A2) + (ΔAh1 ÷ e) × ((e ÷ A1) + t)
... Equation (2)
However, A2 is a discharge current value. For the discharge current value A2, for example, if the discharge current is constant, the discharge current value can be used, and if the discharge current is variable, the average value of the discharge current or the like can be used.

FIG. 5 is a flowchart showing an example of the second charging process of the second embodiment.

The determination unit 111 determines whether the second charging time is less than the chargeable time (S31). When it is determined that the second charging required time is less than the rechargeable time (S31: YES), the charging unit 112 starts discharging the secondary battery 102 (S32). The charging unit 112 discharges the secondary battery 102 until the SOC reaches 0%, and when the SOC reaches 0% (S33: YES), the charging unit 112 stops discharging and the secondary battery 102. Start charging (S34).

The charging unit 112 charges until a predetermined amount of charging is performed, and when the predetermined amount of charging is performed (S35: YES), the charging unit 112 stops charging the secondary battery 102 and leaves it unattended. (S36). When the charging unit 112 is left for a predetermined time and left for a predetermined time (S37: YES), the charging amount Ah and the battery voltage are acquired in association with each other after the leaving is completed (S38).

The charging unit 112 determines whether the SOC of the secondary battery 102 is 100%, and if the SOC is not 100% (S39: NO), the process returns to the process of S34. Then, until the SOC reaches 100%, the processes S34 to S39, in which the secondary battery 102 is intermittently charged while being repeatedly charged by a predetermined amount and left for a predetermined time, are repeatedly executed. When the SOC becomes 100% as a result of repeating the processes of S34 to S39 (S39: YES), the process of FIG. 5 ends.

When it is determined that the second charging time required exceeds the chargeable time (S31: NO), the processes S40 and S41 are executed. Since the processing of S40 and S41 is the same as the normal charging processing executed in S18 and S19 of FIG. 4 of the first embodiment, the description thereof will be omitted.

Therefore, according to the second embodiment, when there is sufficient time required for charging, the battery is discharged until the SOC reaches 0% before charging. After that, the battery is charged by repeating charging a predetermined amount little by little and leaving it for a predetermined time, and at the end of leaving the battery, the charged amount and the battery voltage after the polarization is eliminated are acquired. As a result, it is possible to accurately acquire the charge amount Ah-OCV characteristic after deterioration without being affected by the charge amount Ah-OCV characteristic before deterioration, and to accurately grasp the change in the battery characteristic after deterioration. Can be done. Further, when the SOC reaches 100%, the fully charged capacity after deterioration can be accurately calculated based on the integrated value of the charge amount after each leaving. This makes it possible to grasp the change in the full charge capacity after deterioration.

<Third embodiment>
Since the configuration of the battery monitoring device according to the third embodiment is substantially the same as the configuration of the first embodiment, the description thereof will be omitted with reference to FIG.

In the first embodiment, the determination unit 111 determines whether the first charging time is less than the chargeable time, whereas in the third embodiment, the third charge time is the chargeable time. It differs in that it determines whether it is below.

In the third charging time, the first amount of discharge and the first time of leaving are repeated to intermittently discharge to SOC 0%, and then the second amount of charging and the second time of leaving are repeated. However, it refers to the time required to intermittently charge the battery and acquire the charge amount and the battery voltage in association with each other after the battery is left unattended.

Further, when the determination unit 111 determines that the first charging time is less than the chargeable time, the charging unit 112 of the first embodiment charges the battery while repeating charging a predetermined amount and leaving the battery for a predetermined time. At the end of leaving the battery, the first charge is performed in which the charge amount Ah and the battery voltage are acquired in association with each other.

On the other hand, in the third embodiment, when the third charging time is less than the chargeable time, the charging unit 112 discharges while repeating the first amount of discharging and the first time of leaving. Then, the discharge amount and the battery voltage are obtained in association with each other, and after discharging to SOC 0%, the battery is charged while repeating the charging of the second amount and the leaving for the second time. The difference is that the third charge is performed in which the above is associated and acquired. Therefore, the third charge time is longer than the first charge time and the second charge time. The discharge of the secondary battery 102 to SOC 0% may be performed by the motor 11 and the inverter 12, or may be performed by a load (not shown).

The method for acquiring the third charging time is not particularly limited, but for example, the OCV of the current secondary battery 102, the correlation between the charge / discharge amount Ah and the OCV stored in advance in the storage unit 110, and the correlation. By acquiring the charge amount ΔAh1 required to reach full charge and the discharge amount ΔAh2 required to reach 0% SOC, it can be calculated based on the following equation (3).
(ΔAh2 ÷ e1) × ((e1 ÷ A2) + t1) + (ΔAh1 ÷ e2) × ((e2 ÷ A1) + t2)
... Equation (3)
However, e1 is the first amount (discharge amount) in the intermittent discharge, t1 is the first time of leaving in the intermittent discharge, and e2 is the second amount in the intermittent charge. (Charge amount), and t2 is the second time of neglect in the intermittent charging.

The first quantity e1 and the second quantity e2 of the third embodiment may be the same as the required quantity e of the first embodiment, or may be different amounts from each other. Further, the first time t1 and the second time t2 of the third embodiment may be the same as the required time t of the first embodiment, or may be different times from each other.

Therefore, according to the third embodiment, when there is sufficient time required for charging, the battery is discharged little by little by repeating a predetermined amount of discharge and a predetermined time of leaving, and when the leaving is completed, the discharge amount is determined. By acquiring the battery voltage after the polarization is eliminated, the charge amount Ah-OCV characteristic after deterioration can be acquired.

Further, after discharging until the SOC reaches 0%, the battery is charged by repeating charging a predetermined amount little by little and leaving the battery for a predetermined time, and at the end of leaving the battery, the charged amount and the battery voltage after polarization is eliminated, thereby deteriorating. The later charge amount Ah-OCV characteristic can be acquired. As a result, by acquiring the charge / discharge amount and the battery voltage after polarization elimination acquired during charging and discharging, charging after deterioration is performed with approximately twice the accuracy as compared with the case where it is acquired only during charging or discharging. The quantity Ah-OCV characteristic can be obtained.

Further, when the SOC reaches 100%, the fully charged capacity after deterioration can be calculated based on the integrated value of the charge amount after each leaving.

FIG. 6 is a flowchart showing an example of the third charging process of the third embodiment.

The determination unit 111 determines whether the third charging time is less than the chargeable time (S51). When it is determined that the third charging time is less than the rechargeable time (S51: YES), the charging unit 112 starts discharging the secondary battery 102 (S52). The charging unit 112 discharges until the first amount of discharge is performed, and when the first amount of discharging is performed (S53: YES), the charging unit 112 stops discharging the secondary battery 102. And leave it (S54). When the charging unit 112 is left for the first time and left for the first time (S55: YES), the charging amount Ah and the battery voltage are acquired in association with each other after the leaving is completed (S56).

The charging unit 112 determines whether the SOC has reached 0% (S57), and if the SOC is not 0% (S57: NO), the process returns to the process of S52. Then, until the SOC reaches 0%, the processes of S52 to S57, which intermittently discharge the secondary battery 102 while repeating the discharge of the first amount and the leaving for the first time, are repeatedly executed.

When the SOC reaches 0% (S57: YES), the charging unit 112 stops discharging and starts charging the secondary battery 102 (S58).

The charging unit 112 charges until a second amount of charging is performed, and when the second amount of charging is performed (S59: YES), the charging unit 112 stops charging the secondary battery 102. And leave it (S60). When the charging unit 112 is left for the second time and left for the second time (S61: YES), the charging amount Ah and the battery voltage are acquired in association with each other after the leaving is completed (S62).

The charging unit 112 determines whether the SOC of the secondary battery 102 is 100%, and if the SOC is not 100% (S63: NO), the process returns to the process of S58. Then, until the SOC reaches 100%, the processes of S58 to S63, in which the secondary battery 102 is intermittently charged while repeating the charging of the second amount and the leaving for the second hour, are repeatedly executed. When the SOC becomes 100% as a result of repeating the processes of S58 to S63 (S63: YES), the process of FIG. 6 ends.

When it is determined that the third charging required time exceeds the chargeable time (S51: NO), the processes of S64 and S65 are executed. Since the processing of S64 and S65 is the same as the normal charging processing executed in S18 and S19 of FIG. 4 of the first embodiment, the description thereof will be omitted.

<Fourth Embodiment>
Since the configuration of the battery monitoring device according to the fourth embodiment is substantially the same as the configuration of the first embodiment, the description thereof will be omitted with reference to FIG.

In the first embodiment, the determination unit 111 determines whether the first charging time is less than the chargeable time, whereas in the fourth embodiment, it determines whether the user's operation has been accepted. Is different. Specifically, the determination unit 111 of the fourth embodiment charges the battery while repeating charging a predetermined amount and leaving the battery for a predetermined time based on the operation of the user, and associates the charged amount Ah with the battery voltage at the end of leaving the battery. Determine if the instruction to acquire charging has been accepted.

Further, when the determination unit 111 determines that the first charging time is less than the chargeable time, the charging unit 112 of the first embodiment charges the battery while repeating charging a predetermined amount and leaving the battery for a predetermined time. The first charge is performed to acquire the charge amount Ah and the battery voltage in association with each other at the end of leaving. On the other hand, in the fourth embodiment, when the user's operation is accepted, the charging unit 112 charges the battery while repeating charging a predetermined amount and leaving the battery for a predetermined time, and at the end of leaving the battery, the charging amount Ah and the battery voltage The first charging is performed in which the above is associated and acquired.

Then, in the fourth embodiment, the renewal unit 113 has the charge amount Ah or the charge amount Ah of the secondary battery 102 stored in the storage unit 110 based on each charge amount and the battery voltage acquired by charging the charging unit 112. The correlation between the discharge amount Ah and OCV is updated.

FIG. 7 is a flowchart showing an example of the first charging process of the fourth embodiment.

The determination unit 111 determines whether or not the user's operation has been accepted (S71). When it is determined that the user's operation has been accepted (S71: YES), charging of the secondary battery 102 is started (S72).

The charging unit 112 charges until a predetermined amount of charging is performed, and when the predetermined amount of charging is performed (S73: YES), the charging unit 112 stops charging the secondary battery 102 and leaves it unattended. (S74). When the charging unit 112 is left for a predetermined time and left for a predetermined time (S75: YES), the charging amount Ah and the battery voltage are acquired in association with each other after the leaving is completed (S76).

The charging unit 112 determines whether the SOC of the secondary battery 102 is 100%, and if the SOC is not 100% (S77: NO), the process returns to the process of S72. Then, until the SOC reaches 100%, the processes S72 to S77, which intermittently charge the secondary battery 102 while repeating charging a predetermined amount and leaving the secondary battery 102 for a predetermined time, are repeatedly executed. When the SOC becomes 100% as a result of repeating the processes of S72 to S77 (S77: YES), the update unit 113 stores the storage unit 110 based on each charge amount Ah and the battery voltage acquired in S76. The correlation between the charge amount Ah of the secondary battery 102 and the OCV stored in is updated (S78). When this process is completed, the process of FIG. 7 is completed.

If it is determined that the user's operation is not accepted (S71: NO), the processes of S79 and S80 are executed. Since the processing of S79 and S80 is the same as the normal charging processing executed in S18 and S19 of FIG. 4 of the first embodiment, the description thereof will be omitted.

Therefore, when an explicit instruction is received from the user, the battery is charged by repeating charging a predetermined amount little by little and leaving it for a predetermined time, and at the end of leaving, the charge amount and the battery voltage after polarization elimination are acquired. , The charge amount Ah-OCV characteristic after deterioration can be acquired. Thereby, the change in the battery characteristics can be grasped at the timing desired by the user. Further, when the SOC reaches 100%, the fully charged capacity after deterioration can be calculated based on the integrated value of the charge amount after each leaving and the change amount of the SOC before and after charging. As a result, it is possible to grasp the change in the full charge capacity at the timing desired by the user. Then, the correlation between the battery charge amount stored in the storage unit and the OCV can be updated based on the acquired charge amount and the battery voltage after the polarization is eliminated. This makes it possible to grasp changes in battery characteristics and changes in full charge capacity.

The present invention is not limited to the above embodiments, and various improvements and changes can be made without departing from the gist of the present invention.

1 Electric vehicle 11 Traveling motor 12 Inverter circuit 13 Vehicle ECU
21 Charger 100 Battery pack 101 Battery monitoring device (battery ECU)
102 Rechargeable battery 103 Monitoring ECU
104 Current sensor 105 Thermistor 106, 107 Relay 110 Storage unit 111 Judgment unit 112 Charging unit 113 Update unit

Claims (4)

A determination unit that determines whether the first charging time is less than the chargeable time,
When the above determination is satisfied, a charging unit that charges while repeating a predetermined amount of charging and leaving for a predetermined time, and performs a first charging that acquires the charged amount and the battery voltage in association with each other at the end of leaving.
A battery monitoring device characterized by being equipped with. The battery monitoring device according to claim 1.
The determination unit determines whether the second charging time is less than the chargeable time.
When the second charging time is less than the chargeable time, the charging unit discharges to SOC 0%, charges the battery by repeating charging a predetermined amount and leaving the battery for a predetermined time, and charges the battery at the end of the leaving. A battery monitoring device characterized in that a second charge is performed in which an amount and a battery voltage are acquired in association with each other. The battery monitoring device according to claim 1.
The determination unit determines whether the third charging time is less than the chargeable time.
When the third charging time is less than the rechargeable time, the charging unit discharges the battery while repeating discharging the first amount and leaving the battery for the first time, and associates the discharge amount with the battery voltage. After the battery is discharged to 0% SOC, the battery is charged by repeating the charging of the second amount and leaving for the second time, and at the end of leaving the battery, the charging amount and the battery voltage are associated with each other to obtain the third charge. A battery monitoring device characterized by performing. A storage unit that stores the correlation between the battery charge and OCV,
A judgment unit that determines whether the user's operation has been accepted, and
When the above determination is satisfied, a charging unit that charges while repeating a predetermined amount of charging and leaving for a predetermined time, and performs a first charging that acquires the charged amount and the battery voltage in association with each other at the end of leaving.
An update unit that updates the correlation of the storage unit based on each acquired charge amount and battery voltage, and an update unit.
A battery monitoring device characterized by being equipped with.

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