JP7396385B2 - battery management device - Google Patents

Description

The present disclosure relates to a battery management device.

Conventionally, there is a known technology for determining whether or not the vehicle battery has deteriorated by detecting the state of health (SOH) of the vehicle battery and comparing the degree of deterioration with a threshold value. (For example, see Patent Document 1).

Japanese Patent Application Publication No. 2021-86816

If it is determined that the vehicle battery has deteriorated, the use of the vehicle battery may be restricted and the vehicle may be stopped from running. Therefore, there was room for improvement in terms of safety and convenience.

An object of one aspect of the present disclosure is to provide a battery management device that can ensure safety and improve convenience.

The battery management device according to one aspect of the present disclosure is configured to charge all of the plurality of battery packs after it is determined that one of the plurality of battery packs installed in a vehicle and connected in parallel has deteriorated. a calculation unit that calculates an integrated value of the amount of electricity to be used; and a calculation unit that determines that charging of the vehicle is prohibited when the integrated value exceeds a first threshold value, and then charges a battery pack that is determined to be deteriorated. and a determination unit that determines that discharging of the battery pack determined to be deteriorated is prohibited when the amount is equal to or less than a second threshold value.

According to the present disclosure, it is possible to ensure safety and improve convenience.

A schematic diagram showing the configuration of a battery pack system according to an embodiment of the present disclosure A block diagram showing the configuration of MBMS according to an embodiment of the present disclosure Flowchart showing the operation of MBMS according to the embodiment of the present disclosure

Embodiments of the present disclosure will be described below with reference to the drawings.

First, the configuration of a battery pack system 1 according to the present embodiment will be described using FIG. 1. FIG. 1 is a schematic diagram showing a configuration example of a battery pack system 1. As shown in FIG.

A battery pack system 1 shown in FIG. 1 is mounted on a vehicle (for example, an electric vehicle).

The battery pack system 1 includes one MBMS (Master Battery Management System) 10, a plurality of battery packs 20, and one VCU (Vehicle Control Unit) 30.

The plurality of battery packs 20 are connected in parallel. Each battery pack 20 includes a PBMS (Pack Battery Management System) 21. Although not shown, each battery pack 20 also includes a rechargeable secondary battery, a high voltage relay (for example, a positive relay, a negative relay), a resistor, a voltmeter, an ammeter, etc. . Each battery pack 20 is replaceable.

The VCU 30 is a computer that performs general control of the vehicle.

MBMS 10 is a computer that mainly manages each battery pack 20. Note that the MBMS 10 corresponds to an example of a "battery management device."

The PBMS 21 is a computer that mainly monitors the state of the battery pack 20 and controls the driving of the high voltage relay. Examples of the state of the battery pack 20 include the current, voltage, temperature, degree of deterioration, and state of charge (SOC) in the battery pack 20.

The MBMS 10, VCU 30, and PBMS 21 communicate with each other via CAN (Controller Area Network).

The configuration of the battery pack system 1 has been described above.

Next, the configuration of the MBMS 10 according to this embodiment will be explained using FIG. 2. FIG. 2 is a block diagram showing a configuration example of the MBMS 10.

Although not shown, the MBMS 10 includes hardware such as a CPU (Central Processing Unit), a ROM (Read Only Memory) that stores a computer program, and a RAM (Random Access Memory) that is a working memory. The functions described below are realized by executing a computer program read from the ROM by the CPU in the RAM.

As shown in FIG. 2, the MBMS 10 includes a calculation section 110 and a determination section 120.

When it is determined that one of the plurality of battery packs 20 has deteriorated, the calculation unit 110 calculates an integrated value of the amount of electricity charged in all of the plurality of battery packs 20 (hereinafter referred to as the total amount of charged electricity). Calculate.

Specifically, in each of the plurality of battery packs 20 shown in FIG. 1, the PBMS 21 determines at any time whether the degree of deterioration has fallen below a predetermined deterioration threshold. Then, when the degree of deterioration is less than the deterioration threshold, the PBMS 21 transmits information indicating that the battery pack 20 has deteriorated (hereinafter referred to as deterioration determination information) to the MBMS 10. When the calculation unit 110 of the MBMS 10 receives the deterioration determination information, it starts integrating the total amount of charged electricity from that point.

The determination unit 120 determines whether the integrated value exceeds a predetermined first threshold.

If the integrated value does not exceed the first threshold, the calculation unit 110 continues calculating the integrated value. That is, calculation of the integrated value is repeated until the integrated value exceeds the first threshold value.

On the other hand, if the integrated value exceeds the first threshold, the determination unit 120 determines that charging of the vehicle is prohibited. From now on, charging of the vehicle itself will be prohibited.

Thereafter, the determination unit 120 receives charge amount information from the PBMS 21 of the degraded battery pack 20 (hereinafter referred to as "deteriorated battery pack 20"), and determines whether the charge amount indicated therein is less than or equal to a predetermined second threshold value. Determine whether or not.

If the amount of charge is not less than the second threshold, the determination unit 120 again receives the amount of charge information from the PBMS 21 of the deteriorated battery pack 20, and determines whether the amount of charge indicated therein is less than or equal to the second threshold. .

On the other hand, if the amount of charge is less than or equal to the second threshold, the determination unit 120 determines that discharging of the degraded battery pack 20 is prohibited. After this, discharging of the degraded battery pack 20 is prohibited, and the vehicle becomes unable to run. Note that the determination unit 120 may determine that all battery packs 20, including the degraded battery pack 20, are prohibited from discharging. Furthermore, in the present embodiment, the determination unit 120 makes a determination to prohibit discharging based only on the amount of charge of the degraded battery pack 20; Discharge prohibition may be determined based on the amount.

The configuration of the MBMS 10 has been described above.

Next, the operation of the MBMS 10 will be explained using FIG. 3. FIG. 3 is a flowchart showing the operation of the MBMS 10.

The flow shown in FIG. 3 is started, for example, when the MBMS 10 receives deterioration determination information from one of the plurality of PBMSs 21.

First, the calculation unit 110 performs integration of the total amount of charged electricity (step S1).

Next, the determination unit 120 determines whether the integrated value exceeds the first threshold (step S2).

If the integrated value does not exceed the first threshold (step S2: NO), the flow returns to step S1. In this case, the calculation unit 110 performs the integration of the total amount of charged electricity again.

On the other hand, if the integrated value exceeds the first threshold (step S2: YES), the determination unit 120 determines that charging of the vehicle is prohibited (step S3). From now on, charging of the vehicle itself will be prohibited.

Next, the determination unit 120 receives charge amount information from the PBMS 21 of the deteriorated battery pack 20 (step S4).

Next, the determination unit 120 determines whether the amount of charge indicated in the amount of charge information is less than or equal to the second threshold (step S5).

If the amount of charge is not less than the second threshold (step S5: NO), the flow returns to step S4. In this case, the determination unit 120 receives the charge amount information from the PBMS 21 of the degraded battery pack 20 again.

On the other hand, if the amount of charge is less than or equal to the second threshold (step S5: YES), the determination unit 120 determines that discharge of the degraded battery pack 20 is prohibited (step S6). After this, discharging of the degraded battery pack 20 is prohibited, and the vehicle becomes unable to run. Note that in step S6, the determination unit 120 may determine that all battery packs 20, including the degraded battery pack 20, are prohibited from discharging.

As explained above, the MBMS 10 according to the present embodiment is equipped with a vehicle, and after it is determined that one of the plurality of battery packs connected in parallel has deteriorated, the MBMS 10 A calculation unit 110 that calculates an integrated value of the amount of electricity to be charged, and when the integrated value exceeds a first threshold value, it is determined that charging of the vehicle is prohibited, and thereafter, a battery pack that is determined to be deteriorated is charged. The battery pack is characterized in that it includes a determination unit 120 that determines that discharging of the battery pack determined to be deteriorated is prohibited when the amount of the battery pack is determined to be deteriorated.

Conventionally, when it is determined that a predetermined battery pack has deteriorated, the use of the battery pack is immediately restricted and the vehicle may be stopped from running. Therefore, there was a risk that the vehicle would become stuck in an undesirable location.

In contrast, in the MBMS 10 of the present embodiment, due to the above-mentioned characteristics, even if it is determined that a predetermined battery pack has deteriorated, the integrated value of the total charging electricity amount exceeds the first threshold value, and furthermore, the charging of the deteriorated battery pack The prohibition of charging and discharging can be extended until the amount becomes equal to or less than the second threshold value. Therefore, after it is determined that the battery pack has deteriorated, the vehicle can be driven to a safe location (for example, a location where the battery pack can be replaced). That is, the MBMS 10 of this embodiment can ensure safety and improve convenience.

Note that the present disclosure is not limited to the description of the embodiments described above, and various modifications can be made without departing from the spirit thereof.

The battery management device of the present disclosure is useful as a life extension measure when a battery deteriorates.

1 Battery pack system 10 MBMS
20 Battery pack 21 PBMS
30 VCUs
110 Calculation unit 120 Judgment unit

Claims (2)

A calculation unit that calculates an integrated value of the amount of electricity to be charged to all of the plurality of battery packs after one of the plurality of battery packs mounted on the vehicle and connected in parallel is determined to have deteriorated. and,
When the integrated value exceeds a first threshold value, it is determined that charging of the vehicle is prohibited, and thereafter, when the amount of charge of a battery pack determined to be deteriorated becomes equal to or less than a second threshold value, the deterioration is determined to be prohibited. a determination unit that determines that discharging is prohibited for a battery pack that is determined to be
Battery management device. Each of the plurality of battery packs includes:
It includes a computer that determines deterioration and calculates the amount of charge .
The battery management device includes:
provided outside the plurality of battery packs, and receiving information indicating the result of the determination of deterioration and information indicating the amount of charge from the computer;
The battery management device according to claim 1.

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