US 11,862,798 B2
Positive electrode for non-aqueous electrolyte secondary battery, and non-aqueous electrolyte secondary battery, battery module and battery system using the same
Hikaru Yoshikawa, Tsukuba (JP); and Yuichi Sabi, Tsukuba (JP)
Assigned to SEKISUI CHEMICAL CO., LTD., Osaka (JP)
Filed by SEKISUI CHEMICAL CO., LTD., Osaka (JP)
Filed on Jul. 12, 2022, as Appl. No. 17/862,858.
Application 17/862,858 is a division of application No. 17/768,941, previously published as PCT/JP2022/012904, filed on Mar. 18, 2022.
Claims priority of application No. 2021-045810 (JP), filed on Mar. 19, 2021; and application No. 2021-045971 (JP), filed on Mar. 19, 2021.
Prior Publication US 2022/0359873 A1, Nov. 10, 2022
Int. Cl. H01M 4/58 (2010.01); H01M 4/62 (2006.01); H01M 10/0585 (2010.01); H01M 10/0525 (2010.01); H01M 4/525 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/5825 (2013.01) [H01M 4/525 (2013.01); H01M 4/621 (2013.01); H01M 4/625 (2013.01); H01M 10/0525 (2013.01); H01M 10/0585 (2013.01); H01M 2004/021 (2013.01); H01M 2004/028 (2013.01)] 23 Claims
OG exemplary drawing
 
1. A positive electrode for a non-aqueous electrolyte secondary battery, comprising a positive electrode current collector and a positive electrode active material layer provided on the positive electrode current collector, wherein:
the positive electrode active material layer comprises positive electrode active material particles;
the positive electrode active material particles comprise a positive electrode active material represented by a formula LiFexM(1-x)PO4, wherein 0≤x≤1, and M is Co, Ni, Mn, Al, Ti or Zr;
particles present in the positive electrode active material layer have a median diameter of 1.0 μm to 5.0 μm, based on a volume-based particle size distribution;
when two directions perpendicular to a thickness direction of the positive electrode current collector and orthogonal to each other are defined as a first direction and a second direction,
an average thickness a1, a maximum thickness b1 and a minimum thickness c1 in a thickness distribution in the first direction as well as a thickness d1 which is largest in terms of an absolute value of the difference from the average thickness a1 satisfy inequations 1 and 2:
0.990≤(d1/a1)≤1.010  Inequation 1, and
(b1−c1)≤5.0 μm  Inequation 2, and
an average thickness a2, a maximum thickness b2 and a minimum thickness c2 in a thickness distribution in the second direction as well as a thickness d2 which is largest in terms of an absolute value of the difference from the average thickness a2 satisfy inequations 3 and 4:
0.990≤(d2/a2)≤1.010q  Inequation 3, and
(b2−c2)≤5.0 μm  Inequation 4; and
the positive electrode active material layer has a volume density of 2.10 to 2.50 g/cm3.