US 12,438,384 B2
Cell stabilizing method and system of energy storage system (ESS)
Bo Mi Lim, Daejeon (KR)
Assigned to LG ENERGY SOLUTION, LTD., Seoul (KR)
Appl. No. 17/637,344
Filed by LG ENERGY SOLUTION, LTD., Seoul (KR)
PCT Filed Jul. 1, 2020, PCT No. PCT/KR2020/008589
§ 371(c)(1), (2) Date Feb. 22, 2022,
PCT Pub. No. WO2021/040217, PCT Pub. Date Mar. 4, 2021.
Claims priority of application No. 10-2019-0103486 (KR), filed on Aug. 23, 2019.
Prior Publication US 2022/0311255 A1, Sep. 29, 2022
Int. Cl. H02J 7/00 (2006.01); H01M 10/44 (2006.01); H01M 10/46 (2006.01)
CPC H02J 7/0048 (2020.01) [H01M 10/441 (2013.01); H01M 10/46 (2013.01); H02J 7/0016 (2013.01); H02J 7/0063 (2013.01); H02J 7/00712 (2020.01)] 5 Claims
OG exemplary drawing
 
1. A method for controlling charge/discharge of a plurality of battery cells constituting each battery module included in an energy storage system (ESS), the method comprising:
a charge/discharge step of charging/discharging the plurality of battery cells constituting each battery module;
a data measurement step of measuring state of charge (SOC) measurement data of each battery cell at a predetermined interval while the plurality of battery cells are simultaneously charged/discharged by the charge/discharge step;
an SOC calculation step of calculating a SOC using the measured SOC measurement data of each battery cell;
a maximum/minimum value extraction step of extracting a maximum SOC, which is a largest SOC value for each battery module, and a minimum SOC, which is a smallest SOC value for each battery module, for a same time point using the calculated SOC of each battery cell;
a charge/discharge operation determination step of determining a charge/discharge operation of the plurality of battery cells included in each battery module, based on the extracted maximum SOC and the extracted minimum SOC; and
a charge/discharge operation control step of controlling the charge/discharge operation of the plurality of battery cells included in each battery module, according to the determination result,
wherein the charge/discharge operation determination step comprises:
a first determination step of a first determining to stop the charge/discharge operation of the plurality of battery cells included in each battery module, when the extracted maximum SOC reaches a maximum limit value in a predetermined operation limit range or the extracted minimum SOC reaches a predetermined minimum limit value in the predetermined operation limit range, and
if the first determination step determines to stop the charge/discharge operation, performing a second determination step of performing a second determination based on the first determination, according to a comparison result of comparing whether a calculated difference between the maximum SOC and the minimum SOC exceeds a predetermined reference range, the second determination being the determination result.