US 12,111,362 B2
Battery unit
Kazuki Chiba, Saitama (JP); and Toshiyuki Ariga, Saitama (JP)
Assigned to HONDA MOTOR CO., LTD., Tokyo (JP)
Filed by HONDA MOTOR CO., LTD., Tokyo (JP)
Filed on Dec. 14, 2022, as Appl. No. 18/065,631.
Claims priority of application No. 2022-023918 (JP), filed on Feb. 18, 2022.
Prior Publication US 2023/0266394 A1, Aug. 24, 2023
Int. Cl. G01R 31/374 (2019.01); G01R 31/367 (2019.01); G01R 31/3835 (2019.01); G01R 31/396 (2019.01); H01M 10/44 (2006.01); H01M 10/48 (2006.01); H02J 7/00 (2006.01)
CPC G01R 31/374 (2019.01) [G01R 31/367 (2019.01); G01R 31/3835 (2019.01); G01R 31/396 (2019.01); H01M 10/441 (2013.01); H01M 10/482 (2013.01); H01M 10/486 (2013.01); H01M 2220/20 (2013.01); H02J 7/0048 (2020.01)] 12 Claims
OG exemplary drawing
 
1. A battery unit comprising:
a battery module including battery cells, the battery module including m battery cell groups connected in series, each of the m battery cell groups including n battery cells among the battery cells, the n battery cells being connected in parallel in each of the m battery cell groups, the battery cells totaling (m×n) battery cells;
m voltage detectors provided to the m battery cell groups on a one-to-one basis, each of the m voltage detectors being configured to detect, for an associated one of the m battery cell groups, a composite voltage of the n battery cells;
(m×(n−1)) battery heat flow detectors provided, on a one-to-one basis, to (n−1) battery cells among the n battery cells included in each of the m battery cell groups, each of the (m×(n−1)) battery heat flow detectors being configured to detect a heat flow of an associated one of the (n−1) battery cells;
a storage configured to store (A1) and (A2) below,
(A1): a table map of open circuit voltage OCV vs. state of charge SOC characteristics of the battery cell, and
(A2): a table map of heat flow HF vs. SOC characteristics of the battery cell; and
a battery state estimator configured to estimate SOCs of all the (m×n) battery cells, based on the composite voltage detected for each of the m battery cell groups, the heat flow detected for each of (m×(n−1)) battery cells among the (m×n) battery cells, the (A1), and the (A2),
wherein for each of the m battery cell groups, the battery state estimator is configured to:
determine, based on the (A2), a true SOC of each battery cell of the (n−1) battery cells, the true SOC corresponding to the heat flow detected for the battery cell,
determine, based on the (A1), an OCV of each battery cell of the (n−1) battery cells, the OCV corresponding to the true SOC determined for the battery cell,
calculate an OCV of a remaining one battery cell, from the OCV determined for each battery cell of the (n−1) battery cells and the composite voltage detected, and
determine, based on the (A1), a true SOC of the remaining one battery cell, the true SOC corresponding to the OCV calculated for the remaining one battery cell.