US 12,126,013 B2
Non-aqueous electrolyte secondary cell
Junichi Sugaya, Osaka (JP); Takuya Shinomiya, Osaka (JP); Takamitsu Tashita, Tokushima (JP); Fumikazu Mizukoshi, Tokushima (JP); and Tsukasa Gejo, Osaka (JP)
Assigned to PANASONIC ENERGY CO., LTD., Osaka (JP); and PANASONIC HOLDINGS CORPORATION, Osaka (JP)
Appl. No. 17/058,865
Filed by SANYO Electric Co., Ltd., Daito (JP); and Panasonic Corporation, Kadoma (JP)
PCT Filed Mar. 8, 2019, PCT No. PCT/JP2019/009257
§ 371(c)(1), (2) Date Nov. 25, 2020,
PCT Pub. No. WO2019/239652, PCT Pub. Date Dec. 19, 2019.
Claims priority of application No. 2018-114169 (JP), filed on Jun. 15, 2018.
Prior Publication US 2021/0159489 A1, May 27, 2021
Int. Cl. H01M 4/133 (2010.01); H01M 4/02 (2006.01); H01M 4/134 (2010.01); H01M 4/36 (2006.01); H01M 4/38 (2006.01); H01M 4/587 (2010.01); H01M 10/0525 (2010.01)
CPC H01M 4/364 (2013.01) [H01M 4/133 (2013.01); H01M 4/134 (2013.01); H01M 4/386 (2013.01); H01M 4/587 (2013.01); H01M 10/0525 (2013.01); H01M 2004/021 (2013.01); H01M 2004/027 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A non-aqueous electrolyte secondary battery comprising:
a positive electrode including a positive electrode current collector and a positive electrode active material layer disposed on the positive electrode current collector, wherein the positive electrode active material includes a lithium/transition metal oxide containing lithium and a transition metal element,
a negative electrode including a negative electrode current collector and a negative electrode active material layer disposed on the negative electrode current collector, and
a non-aqueous electrolyte, wherein
the non-aqueous electrolyte includes a non-aqueous solvent, and an electrolyte salt dissolved in the non-aqueous solvent, and
the non-aqueous solvent includes fluoroethylene carbonate; wherein
the negative electrode active material layer includes graphite particles A and graphite particles B each as a negative electrode active material, wherein the graphite particles A and the graphite particles B are configured to reversibly intercalate and deintercalate lithium ions,
the graphite particles A have a porosity due to closed pores of 5% or less and the graphite particles B have a porosity due to closed pores of 8% to 20%, wherein the porosity due to closed pores is an average percentage of a total area of closed pores relative to a cross sectional area of each of the graphite particles A and the graphite particles B, wherein the closed pores are not linked from internals of a graphite particle to an external surface of the graphite particle, and
the graphite particles A are more included in a half region on an outer surface side than in a half region on a negative electrode current collector side in the case of bisection of the negative electrode active material layer in a thickness direction.