US 12,009,512 B2
Nonaqueous electrolyte secondary battery
Takamasa Tamura, Osaka (JP); Nobuhiro Sakitani, Tokushima (JP); and Takaharu Morikawa, Osaka (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Appl. No. 17/054,881
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
PCT Filed Apr. 26, 2019, PCT No. PCT/JP2019/017893
§ 371(c)(1), (2) Date Nov. 12, 2020,
PCT Pub. No. WO2019/230298, PCT Pub. Date Dec. 5, 2019.
Claims priority of application No. 2018-103824 (JP), filed on May 30, 2018.
Prior Publication US 2021/0218019 A1, Jul. 15, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. H01M 4/38 (2006.01); H01M 4/36 (2006.01); H01M 4/58 (2010.01); H01M 4/583 (2010.01); H01M 4/587 (2010.01); H01M 4/64 (2006.01); H01M 10/0525 (2010.01); H01M 10/0587 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/386 (2013.01) [H01M 4/364 (2013.01); H01M 4/583 (2013.01); H01M 4/587 (2013.01); H01M 4/64 (2013.01); H01M 10/0525 (2013.01); H01M 10/0587 (2013.01); H01M 2004/021 (2013.01); H01M 2004/027 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A nonaqueous electrolyte secondary battery comprising a spirally wound electrode body in which a positive electrode and a negative electrode are spirally wound with a separator interposed therebetween,
wherein the negative electrode includes a negative electrode current collector, a first negative electrode mixture layer disposed on a first surface of the negative electrode current collector, and a second negative electrode mixture layer disposed on a second surface of the negative electrode current collector, the first surface and the second surface facing outward and inward of the electrode body, respectively,
wherein the first negative electrode mixture layer includes a Si active material composed of at least one of Si and a Si-containing material,
wherein a content of the Si active material in terms of Si is lower in a portion of the first negative electrode mixture layer which faces the negative electrode current collector in a thickness direction of the first negative electrode mixture layer, than in a portion of the first negative electrode mixture layer which faces a surface of the first negative electrode mixture layer in the thickness direction,
wherein the second negative electrode mixture layer includes the Si active material, and
wherein the content of the Si active material in terms of Si is lower in a portion of the second negative electrode mixture layer which faces a surface of the second negative electrode mixture layer in a thickness direction of the second negative electrode mixture layer, than in a portion of the second negative electrode mixture layer which faces the negative electrode current collector in the thickness direction.