US 12,347,866 B2
Lithium ion secondary battery and production method thereof
Kei Shimamoto, Shimonoseki (JP); Takao Fukunaga, Tokyo (JP); Hideyuki Sugiyama, Tokyo (JP); Wataru Masuda, Aki-gun (JP); Hiroki Fujita, Aki-gun (JP); and Munetaka Higuchi, Aki-gun (JP)
Assigned to Mazda Motor Corporation, Hiroshima (JP)
Filed by Mazda Motor Corporation, Hiroshima (JP)
Filed on Sep. 9, 2021, as Appl. No. 17/447,228.
Claims priority of application No. 2020-156071 (JP), filed on Sep. 17, 2020.
Prior Publication US 2022/0085377 A1, Mar. 17, 2022
Int. Cl. H01M 4/62 (2006.01); H01M 4/58 (2010.01); H01M 4/587 (2010.01); H01M 10/0525 (2010.01); H01M 10/0569 (2010.01); H01M 10/0587 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/628 (2013.01) [H01M 4/5825 (2013.01); H01M 4/587 (2013.01); H01M 10/0525 (2013.01); H01M 10/0569 (2013.01); H01M 10/0587 (2013.01); H01M 2004/027 (2013.01); H01M 2004/028 (2013.01); H01M 2220/20 (2013.01)] 14 Claims
 
1. A lithium ion secondary battery comprising: a positive electrode having a positive electrode active material layer on a surface of a positive electrode collector; a negative electrode having a negative electrode active material layer on a surface of a negative electrode collector; a nonaqueous electrolyte, the positive electrode, the negative electrode, and the nonaqueous electrolyte being accommodated in a battery case,
the nonaqueous electrolyte containing γ-butyrolactone as a main component of a nonaqueous solvent;
a coat containing a component derived from vinylene carbonate on a surface of the negative electrode active material layer; and
a coat containing a component derived from monoalkyl sulfate ions on a surface of the positive electrode active material layer, wherein
the coat formed on the surface of the positive electrode active material layer further contains a component derived from bis(oxalate)borate ions,
one surface of the coat formed on the surface of the negative electrode active material layer directly contacts the surface of the negative electrode active material layer, whereas the other surface of the coat formed on the surface of the negative electrode active material layer directly contacts the nonaqueous electrolyte, and
one surface of the coat formed on the surface of the positive electrode active material layer directly contacts the surface of the positive electrode active material layer, whereas the other surface of the coat formed on the surface of the positive electrode active material layer directly contacts the nonaqueous electrolyte.