US 11,888,154 B2
Positive electrode sheet, secondary battery, battery module, battery pack and electrical apparatus
Xiang Zhou, Fujian (CN); Jiang Liu, Fujian (CN); Baiqing Li, Fujian (CN); Yao Jiang, Fujian (CN); and Xiaomei Liu, Fujian (CN)
Assigned to CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Ningde (CN)
Filed by CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Fujian (CN)
Filed on Jun. 20, 2023, as Appl. No. 18/211,591.
Application 18/211,591 is a continuation of application No. PCT/CN2022/079269, filed on Mar. 4, 2022.
Prior Publication US 2023/0352663 A1, Nov. 2, 2023
Int. Cl. H01M 4/36 (2006.01); H01M 4/505 (2010.01); H01M 4/58 (2010.01); H01M 4/525 (2010.01); H01M 4/583 (2010.01); H01M 4/02 (2006.01); H01M 10/052 (2010.01)
CPC H01M 4/366 (2013.01) [H01M 4/505 (2013.01); H01M 4/525 (2013.01); H01M 4/583 (2013.01); H01M 4/5825 (2013.01); H01M 10/052 (2013.01); H01M 2004/028 (2013.01); H01M 2220/20 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A positive electrode sheet, comprising a positive electrode current collector and a positive electrode film layer provided on at least one surface of the positive electrode current collector; the positive electrode film layer is of a single-layer structure or a multi-layer structure; when the positive electrode film layer is of a single-layer structure, at least one of the positive electrode film layers comprises both a first positive electrode active material having a core-shell structure and a second positive electrode active material; and/or, when the positive electrode film layer is of a multi-layer structure, at least one layer of at least one of the positive electrode film layers comprises both a first positive electrode active material having a core-shell structure and a second positive electrode active material;
the first positive electrode active material comprises an inner core, a first coating layer covering the inner core and a second coating layer covering the first coating layer; wherein the inner core comprises Li1+xMn1-yAyP1-zRzO4, the first coating layer comprises pyrophosphate MP2O7 and phosphate XPO4, and the second coating layer comprises carbon element;
wherein,
A is selected from one or more elements of Zn, Al, Na, K, Mg, Mo, W, Ti, V, Zr, Fe, Ni, Co, Ga, Sn, Sb, Nb and Ge;
R is selected from one or more elements of B, Si, N and S;
x is selected from any value in the range of −0.100-0.100;
y is selected from any value in the range of 0.001-0.500;
z is selected from any value in the range of 0.001-0.100;
M and X are independently selected from one or more elements of Li, Fe, Ni, Mg, Co, Cu, Zn, Ti, Ag, Zr, Nb and Al; and
the second positive electrode active material is selected from one or more of LiNiaCobMn(1-a-b)O2, LiNiaCobAl(1-a-b)O2 and LiCoO2; wherein a is independently selected from any value in the range of 0.3-0.9, and the sum of a and b is independently selected from any value in the range of 0.3-0.9.