US 12,345,771 B2
Apparatus and method for determining defect of battery cell
Chang Mook Hwang, Daejeon (KR); Jong Hyuk Lee, Daejeon (KR); and Yoon Ji Jo, Daejeon (KR)
Assigned to SK ON CO., LTD., Seoul (KR)
Filed by SK ON CO., LTD., Seoul (KR)
Filed on Mar. 30, 2023, as Appl. No. 18/192,648.
Claims priority of application No. 10-2022-0043029 (KR), filed on Apr. 6, 2022.
Prior Publication US 2023/0324470 A1, Oct. 12, 2023
Int. Cl. G01R 31/392 (2019.01); G01R 31/374 (2019.01); G01R 31/385 (2019.01); G01R 31/388 (2019.01)
CPC G01R 31/392 (2019.01) [G01R 31/374 (2019.01); G01R 31/3865 (2019.01); G01R 31/388 (2019.01)] 15 Claims
OG exemplary drawing
 
1. An apparatus for determining a defect of a battery cell (“a defect determination apparatus”), the apparatus comprising:
a temperature measurement unit configured to measure an aging temperature of the battery cell;
a period determination unit configured to determine an aging period of the battery cell;
an SOC determination unit configured to measure and determine a state of charge (SOC) of the battery cell at the start of aging;
a voltage measurement unit configured to measure open circuit voltages (OCVs) of the battery cell at the start of aging and at the end of aging; and
a defect determination unit configured to determine whether the battery cell is defective based on the aging temperature, the aging period, the SOC at the start of aging, the OCV at the start of aging and the OCV at the end of aging,
wherein the defect determination unit calculates a self-discharge voltage and an allowable deviation using the aging temperature, the aging period and the SOC at the start of aging,
calculates the defect determination reference voltage by subtracting the self-discharge voltage and the allowable deviation from the OCV at the start of aging, and
determines the battery cell is defective when the OCV at the end of aging is less than the determined defect determination reference voltage.