US 11,901,561 B2
Positive electrode sheet and secondary battery including the same, battery module, battery pack, and electrical apparatus
Quanguo Li, Ningde (CN); Yonghuang Ye, Ningde (CN); Songjun Shi, Ningde (CN); Qian Liu, Ningde (CN); Jun Peng, Ningde (CN); and Fajun Huang, Ningde (CN)
Assigned to CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Ningde (CN)
Filed by CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Ningde (CN)
Filed on Dec. 20, 2022, as Appl. No. 18/069,067.
Application 18/069,067 is a continuation of application No. PCT/CN2021/134825, filed on Dec. 1, 2021.
Prior Publication US 2023/0170491 A1, Jun. 1, 2023
Int. Cl. H01M 4/62 (2006.01); H01M 4/525 (2010.01); H01M 4/505 (2010.01); H01M 4/02 (2006.01)
CPC H01M 4/628 (2013.01) [H01M 4/505 (2013.01); H01M 4/525 (2013.01); H01M 4/623 (2013.01); H01M 4/625 (2013.01); H01M 2004/021 (2013.01); H01M 2004/028 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A positive electrode sheet for a secondary battery, comprising:
a current collector comprising a coating region and a non-coating region other than the coating region;
a resistance layer disposed on the current collector and comprising a conductive agent, a first binder, and a first positive electrode active material; and
a positive electrode active material layer comprising a second positive electrode active material, a conductive agent, and a second binder;
wherein:
a resistance of the resistance layer is greater than a resistance of the positive electrode active material layer;
in a cross section of the positive electrode sheet, a projection of at least a part of the positive electrode active material layer on the current collector and a projection of the resistance layer on the current collector do not overlap, and
a polarization parameter P of the positive electrode sheet is in a range of 0.4-65.0, and the polarization parameter P=((1−S)/S)·(R1/R2), wherein S is an area ratio of the resistance layer relative to the coating region of the current collector, R1 is a film resistance value of the positive electrode sheet in a part where the resistance layer is provided, and R2 is a film resistance value of the positive electrode sheet in a part of the coating region where the resistance layer is not provided.