US 11,942,645 B2
Non-aqueous electrolyte secondary battery having separator with multilayer structure
Akihiko Takada, Hyogo (JP); Masanori Sugimori, Hyogo (JP); Nobuhiro Hirano, Osaka (JP); Yuki Morikawa, Hyogo (JP); Yasunori Baba, Hyogo (JP); and Katsunori Yanagida, Hyogo (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Appl. No. 16/640,226
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
PCT Filed Nov. 2, 2018, PCT No. PCT/JP2018/040794
§ 371(c)(1), (2) Date Feb. 19, 2020,
PCT Pub. No. WO2019/107068, PCT Pub. Date Jun. 6, 2019.
Claims priority of application No. 2017-230504 (JP), filed on Nov. 30, 2017.
Prior Publication US 2020/0251744 A1, Aug. 6, 2020
Int. Cl. H01M 4/66 (2006.01); H01M 2/16 (2006.01); H01M 4/36 (2006.01); H01M 4/58 (2010.01); H01M 4/62 (2006.01); H01M 10/0525 (2010.01); H01M 50/417 (2021.01); H01M 50/423 (2021.01); H01M 50/431 (2021.01); H01M 50/434 (2021.01); H01M 50/451 (2021.01); H01M 50/457 (2021.01); H01M 50/46 (2021.01); H01M 4/02 (2006.01)
CPC H01M 4/668 (2013.01) [H01M 4/366 (2013.01); H01M 4/58 (2013.01); H01M 4/624 (2013.01); H01M 10/0525 (2013.01); H01M 50/417 (2021.01); H01M 50/423 (2021.01); H01M 50/431 (2021.01); H01M 50/434 (2021.01); H01M 50/451 (2021.01); H01M 50/457 (2021.01); H01M 50/46 (2021.01); H01M 2004/021 (2013.01); H01M 2004/027 (2013.01); H01M 2004/028 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A non-aqueous electrolyte secondary battery comprising: a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode,
wherein the separator has a multilayer structure including a porous resin substrate, a first filler layer containing phosphate particles, and a second filler layer containing inorganic particles having higher heat resistance than the phosphate particles,
the second filler layer is disposed on the porous resin substrate,
the first filler layer is disposed on the porous resin substrate or the second filler layer in such a manner that a surface of the first filler layer faces a surface of the negative electrode, and
the phosphate particles have a BET specific surface area in a range of 5 m2/g or more to 100 m2/g or less,
wherein a porosity of the porous resin substrate is in a range of 30% or more to 70% or less,
wherein the phosphate particles have an average particle size that is smaller than an average pore size of the porous resin substrate and that is in a range of from 0.05 μm to 1 μm,
wherein the first filler layer comprises a continuous layer configured to cover an entirety of a surface of the porous resin substrate or the second filler layer on which the first filler layer is disposed,
wherein the phosphate particles are configured to melt and flow into pores of the porous resin substrate and simultaneously to undergo polycondensation to form a coating film of a phosphate polycondensation product on the negative electrode in response to an exothermic reaction on a surface of the negative electrode, and
wherein a porosity of the first filler layer is 30% or more and 70% or less.