# US 2025/0085353 A1 · Battery diagnosis apparatus

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- Number: US 2025/0085353 A1
- Document ID: US20250085353A1
- Status: Published application
- Kind: A1
- Application number: 18/564,582
- Filed: 2022-07-14
- Published: 2025-03-13
- Earliest claimed: 2022-07-14
- Assignees: Subaru Corporation
- Applicants: Subaru Corporation
- Inventors: Noboru OYAMA; Shuichiro YAMAGUCHI; Yasuhiko OHSAWA; Yasumasa MOCHIZUKI; Rin FURUDATE; Hiroshi ABE
- Web page: https://patentgrep.com/patent/US20250085353A1

## CPC

- G01R 31/3842: combining voltage and current measurements
- G01R 31/36: Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
- G01R 31/378: specially adapted for the type of battery or accumulator
- G01R 31/389: Measuring internal impedance, internal conductance or related variables
- G01R 31/392: Determining battery ageing or deterioration, e.g. state of health
- H01M 10/425: {Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing (printed circuits H05K1/00)}
- H01M 10/4285: {Testing apparatus}
- H01M 10/48: Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte (constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569)
- Y02E 60/10: Energy storage using batteries
- G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12)
- H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION

## Abstract

A battery diagnosis apparatus includes a current source configured to apply a pulse current to a battery, a voltage sensor configured to detect a voltage between terminals of the battery, and a control device. The control device includes one or more processors and one or more memories coupled to the one or more processors. The one or more processors are configured to execute processing including acquiring a voltage response obtained by applying the pulse current from the current source to the battery; deriving, based on the voltage response, an index indicating a comparison between an on-ATRF and an off-ATRF, the on-ATRF being an apparent transient resistance function of the battery when the pulse current is turned on, the off-ATRF being an apparent transient resistance function of the battery when the pulse current is turned off; and determining a degree of deposition of lithium in the battery, based on the derived index.

## Claims

### Claim 1

A battery diagnosis apparatus for diagnosing a state of a battery, the battery diagnosis apparatus comprising:
a current source configured to apply a pulse current to the battery;
a voltage sensor configured to detect a voltage between terminals of the battery; and
a control device, wherein
the control device comprises:
one or more processors; and
one or more memories coupled to the one or more processors, and
the one or more processors are configured to execute processing comprising:
acquiring a voltage response obtained by applying the pulse current from the current source to the battery;
deriving, based on the voltage response, an index indicating a comparison between an on-ATRF and an off-ATRF, the on-ATRF being an apparent transient resistance function of the battery when the pulse current is turned on, the off-ATRF being an apparent transient resistance function of the battery when the pulse current is turned off; and
determining a degree of deposition of lithium in the battery, based on the derived index.

### Claim 2 (depends on 1)

The battery diagnosis apparatus according to claim 1, wherein the index is a resistance function ratio indicating a ratio of the off-ATRF to the on-ATRF.

### Claim 3 (depends on 1)

The battery diagnosis apparatus according to claim 1, wherein the index indicates a comparison between the on-ATRF at a timing at which a specific time has elapsed from a timing of a rising edge of a voltage in response to turning on of the pulse current and the off-ATRF at a timing at which the specific time has elapsed from a timing of a falling edge of the voltage in response to turning off of the pulse current.

### Claim 4 (depends on 3)

The battery diagnosis apparatus according to claim 3, wherein
in the deriving of the index, the one or more processors are configured to execute processing comprising deriving a plurality of the indices having different specific times, and
in the determining of the degree of deposition of lithium in the battery, the one or more processors are configured to execute processing comprising determining the degree of deposition of lithium in the battery, based on an average value of the plurality of indices.

### Claim 5 (depends on 1)

The battery diagnosis apparatus according to claim 1, wherein
in the acquiring of the voltage response, the one or more processors are configured to execute processing comprising applying a plurality of the pulse currents having different current values to the battery in stages to acquire the voltage response for each of the current values,
in the deriving of the index, the one or more processors are configured to execute processing comprising deriving the index for each of the current values, based on the voltage response for the current value, and
in the determining of the degree of deposition of lithium in the battery, the one or more processors are configured to execute processing comprising determining the degree of deposition of lithium in the battery, based on a plurality of the respective indices for the current values.

### Claim 6 (depends on 1)

The battery diagnosis apparatus according to claim 1, further comprising an SOC adjustment device configured to adjust an SOC of the battery, wherein
the one or more processors are configured to execute processing comprising:
when the SOC of the battery is out of a preset predetermined range before the pulse current is applied to the battery, causing the SOC adjustment device to adjust the SOC of the battery so that the SOC of the battery falls within the predetermined range.

### Claim 7 (depends on 1)

The battery diagnosis apparatus according to claim 1, wherein
the one or more processors are configured to execute processing comprising determining a determination criterion for determining the degree of deposition of lithium in the battery, based on a temperature of the battery before applying the pulse current to the battery, and
in the determining of the degree of deposition of lithium in the battery, the one or more processors are configured to execute processing comprising comparing the determined determination criterion with the index to determine the degree of deposition of lithium in the battery.

### Claim 8 (depends on 2)

The battery diagnosis apparatus according to claim 2, wherein the index indicates a comparison between the on-ATRF at a timing at which a specific time has elapsed from a timing of a rising edge of a voltage in response to turning on of the pulse current and the off-ATRF at a timing at which the specific time has elapsed from a timing of a falling edge of the voltage in response to turning off of the pulse current.

### Claim 9 (depends on 8)

The battery diagnosis apparatus according to claim 8, wherein
in the deriving of the index, the one or more processors are configured to execute processing comprising deriving a plurality of the indices having different specific times, and
in the determining of the degree of deposition of lithium in the battery, the one or more processors are configured to execute processing comprising determining the degree of deposition of lithium in the battery, based on an average value of the plurality of indices.

### Claim 10 (depends on 2)

The battery diagnosis apparatus according to claim 2, wherein
in the acquiring of the voltage response, the one or more processors are configured to execute processing comprising applying a plurality of the pulse currents having different current values to the battery in stages to acquire the voltage response for each of the current values,
in the deriving of the index, the one or more processors are configured to execute processing comprising deriving the index for each of the current values, based on the voltage response for the current value, and
in the determining of the degree of deposition of lithium in the battery, the one or more processors are configured to execute processing comprising determining the degree of deposition of lithium in the battery, based on a plurality of the respective indices for the current values.

### Claim 11 (depends on 2)

The battery diagnosis apparatus according to claim 2, further comprising an SOC adjustment device configured to adjust an SOC of the battery, wherein
the one or more processors are configured to execute processing comprising:
when the SOC of the battery is out of a preset predetermined range before the pulse current is applied to the battery, causing the SOC adjustment device to adjust the SOC of the battery so that the SOC of the battery falls within the predetermined range.

### Claim 12 (depends on 2)

The battery diagnosis apparatus according to claim 2, wherein
the one or more processors are configured to execute processing comprising determining a determination criterion for determining the degree of deposition of lithium in the battery, based on a temperature of the battery before applying the pulse current to the battery, and
in the determining of the degree of deposition of lithium in the battery, the one or more processors are configured to execute processing comprising comparing the determined determination criterion with the index to determine the degree of deposition of lithium in the battery.