US 12,255,332 B2
Secondary battery, battery module, battery pack and electric device
Cuiping Zhang, Fujian (CN); Changlong Han, Fujian (CN); and Peng Fan, Fujian (CN)
Assigned to CONTEMPORARY AMPEREX TECHNOLOGY (HONG KONG) LIMITED, Hong Kong (CN)
Filed by CONTEMPORARY AMPEREX TECHNOLOGY (HONG KONG) LIMITED, Hong Kong (CN)
Filed on Dec. 4, 2023, as Appl. No. 18/527,410.
Application 18/527,410 is a continuation of application No. PCT/CN2022/096609, filed on Jun. 1, 2022.
Prior Publication US 2024/0105942 A1, Mar. 28, 2024
Int. Cl. H01M 10/0568 (2010.01); H01M 4/583 (2010.01); H01M 50/209 (2021.01); H01M 4/02 (2006.01); H01M 10/052 (2010.01)
CPC H01M 4/583 (2013.01) [H01M 10/0568 (2013.01); H01M 50/209 (2021.01); H01M 2004/021 (2013.01); H01M 2004/027 (2013.01); H01M 10/052 (2013.01); H01M 2220/20 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A secondary battery, comprising
an electrode assembly and an electrolytic solution configured to infiltrate the electrode assembly, wherein
the electrode assembly comprises a negative electrode plate, a separation film and a positive electrode plate, and the negative electrode plate includes a negative electrode current collector and a negative electrode material layer located on at least one surface of the negative electrode current collector;
by setting a tortuosity of the negative electrode plate as τ, the τ satisfies Formula I below:
τ=0.5(ε)−α  Formula I
where, ε is a porosity of the negative electrode material layer, and α is a Bruggeman index of the negative electrode material layer,
the τ and a conductivity σ of the electrolytic solution satisfy Formula II below:
6≤σ−(2τ)0.5≤10  Formula II,
the τ satisfies: 4.9≤τ≤7, and
the σ ranges from 8 mS/cm to 14 mS/cm.