US 12,424,654 B2
Secondary battery
Tomomi Sakuma, Kyoto (JP); Shinichi Katayama, Kyoto (JP); and Hideki Nakai, Kyoto (JP)
Assigned to Murata Manufacturing Co., Ltd., Kyoto (JP)
Filed by MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed on Dec. 29, 2022, as Appl. No. 18/090,780.
Application 18/090,780 is a continuation of application No. PCT/JP2021/032812, filed on Sep. 7, 2021.
Claims priority of application No. 2020-156446 (JP), filed on Sep. 17, 2020.
Prior Publication US 2023/0132785 A1, May 4, 2023
Int. Cl. H01M 10/0525 (2010.01); H01M 4/02 (2006.01); H01M 4/136 (2010.01); H01M 4/36 (2006.01)
CPC H01M 10/0525 (2013.01) [H01M 4/136 (2013.01); H01M 4/366 (2013.01); H01M 2004/027 (2013.01); H01M 2004/028 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A secondary battery comprising:
a positive electrode;
a negative electrode;
a negative electrode wiring line coupled to the negative electrode; and
an electrolytic solution, wherein
the negative electrode includes a negative electrode active material layer and a film, the film covering a surface of the negative electrode active material layer,
the film includes sulfur as a constituent element,
the electrolytic solution includes a chain carboxylic acid ester, and,
where the film is divided, in a direction away from the negative electrode wiring line, into thirds including a first film part, a second film part, and a third film part,
a content of sulfur in the first film part, the third film part, or each of the first film part and the third film part is greater than or equal to 11 micromoles per square meter and less than or equal to 22 micromoles per square meter,
a content of sulfur in the second film part is greater than or equal to 7 micromoles per square meter and less than or equal to 13 micromoles per square meter, and
a ratio of the content of sulfur in the first film part, the third film part, or each of the first film part and the third film part to the content of sulfur in the second film part is greater than or equal to 1.2 and less than or equal to 2.1.