US 12,087,942 B2
Nonaqueous electrolyte secondary battery
Yuji Tani, Osaka (JP); Junichi Sakamoto, Osaka (JP); and Nobuhiko Hojo, Osaka (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Appl. No. 17/442,058
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
PCT Filed Mar. 23, 2020, PCT No. PCT/JP2020/012765
§ 371(c)(1), (2) Date Sep. 22, 2021,
PCT Pub. No. WO2020/203420, PCT Pub. Date Oct. 8, 2020.
Claims priority of application No. 2019-067637 (JP), filed on Mar. 29, 2019.
Prior Publication US 2022/0173389 A1, Jun. 2, 2022
Int. Cl. H01M 4/38 (2006.01); H01M 4/02 (2006.01); H01M 4/133 (2010.01); H01M 4/134 (2010.01); H01M 4/36 (2006.01); H01M 4/48 (2010.01); H01M 4/485 (2010.01); H01M 4/587 (2010.01); H01M 10/0525 (2010.01); H01M 10/42 (2006.01)
CPC H01M 4/386 (2013.01) [H01M 4/133 (2013.01); H01M 4/134 (2013.01); H01M 4/364 (2013.01); H01M 4/483 (2013.01); H01M 4/485 (2013.01); H01M 4/587 (2013.01); H01M 10/0525 (2013.01); H01M 2004/027 (2013.01); H01M 2010/4292 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A non-aqueous electrolyte secondary battery including a positive electrode, a negative electrode, an electrolyte and a separator disposed between the positive electrode and the negative electrode,
the negative electrode including a negative electrode mixture layer having a thickness T and a negative electrode current collector carrying the negative electrode mixture layer,
the negative electrode active material including a carbon material and a Si-containing material,
the Si-containing material including a first composite material and a second composite material different from the first composite material,
the first composite material including a silicon oxide phase and a first Si particles dispersed in the silicon oxide phase,
wherein when the negative electrode mixture layer is divided into a first region having a thickness of T/2 on the surface side of the negative electrode and a second region having a thickness of T/2 on the negative electrode collector side,
a ratio of a mass w11 of the first composite material contained in the first region to a mass w12 of the second composite material contained in the first region: w11/w12 is greater than 1,
a ratio of a mass w21 of the first composite material contained in the second region to a mass w22 of the second composite material contained in the second region: w21/w22 is less than 1, and,
in a fully charged condition, an open circuit potential of the negative electrode is 0 V or more and 70 mV or less with respect to a lithium metal.