US 11,923,543 B2
Nonaqueous electrolyte secondary battery
Yoshio Kato, Osaka (JP); Yoshinori Kida, Hyogo (JP); and Masahiro Shiraga, Osaka (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Appl. No. 17/049,384
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
PCT Filed Feb. 22, 2019, PCT No. PCT/JP2019/006750
§ 371(c)(1), (2) Date Oct. 21, 2020,
PCT Pub. No. WO2019/207933, PCT Pub. Date Oct. 31, 2019.
Claims priority of application No. 2018-086477 (JP), filed on Apr. 27, 2018.
Prior Publication US 2021/0249658 A1, Aug. 12, 2021
Int. Cl. H01M 4/583 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/583 (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 negative electrode contains graphite particles having a volume per mass of micropores having a micropore size of 2 nm or less, of 0.3 mm3/g or less, as determined from a nitrogen adsorption isotherm according to a DFT method, as a negative electrode active material,
a ratio of areas of internal pores to a total cross sectional area in a SEM image of cross sections of the graphite particles is 0.14 or less, and
the graphite particles have surfaces coated with a carbonized product.