US 11,936,031 B2
Non-aqueous electrolyte secondary battery including a positive electrode active substance containing a lithium composite oxide porous particle and a rock salt layer
Yuji Yamamoto, Toyota (JP); Momoko Procter, Seto (JP); Yoshinari Makimura, Nisshin (JP); Tetsutaro Hayashi, Niihama (JP); and Willy Shun Kai Bong, Niihama (JP)
Assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota (JP); and SUMITOMO METAL MINING CO., LTD., Tokyo (JP)
Filed by TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota (JP); and SUMITOMO METAL MINING CO., LTD., Tokyo (JP)
Filed on Jul. 10, 2020, as Appl. No. 16/926,163.
Claims priority of application No. 2019-133134 (JP), filed on Jul. 18, 2019.
Prior Publication US 2021/0020900 A1, Jan. 21, 2021
Int. Cl. H01M 4/131 (2010.01); H01M 4/02 (2006.01); H01M 4/36 (2006.01); H01M 4/525 (2010.01); H01M 10/0525 (2010.01)
CPC H01M 4/131 (2013.01) [H01M 4/366 (2013.01); H01M 4/525 (2013.01); H01M 10/0525 (2013.01); H01M 2004/021 (2013.01); H01M 2004/027 (2013.01); H01M 2004/028 (2013.01)] 3 Claims
OG exemplary drawing
 
1. A non-aqueous electrolyte secondary battery comprising a positive electrode, a negative electrode and a non-aqueous electrolyte, wherein
the positive electrode is provided with a positive electrode active substance layer,
the positive electrode active substance layer contains a lithium composite oxide having a layered structure,
the lithium composite oxide includes a porous particle having a surface portion, the surface portion having an outer surface,
the surface portion of the porous particle comprises a layer having an α-NaCl crystal structure, wherein a thickness of the layer is not less than 5 nm but not more than 80 nm,
a void ratio of the porous particle is not less than 15% but not more than 48%,
the porous particle contains two or more voids having diameters that are at least 10% of a particle diameter of the porous particle, and
the outer surface of the porous particle is provided with a coating of lithium tungstate.