US 11,909,000 B2
Lithium-ion secondary battery, battery module, battery pack, and powered device
Chang Peng, Ningde (CN); Peipei Chen, Ningde (CN); Hailin Zou, Ningde (CN); and Chengdu Liang, Ningde (CN)
Assigned to CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Ningde (CN)
Filed by CONTEMPORARY AMPEREX TECHNOLOGY CO., LIMITED, Ningde (CN)
Filed on Aug. 19, 2022, as Appl. No. 17/820,944.
Application 17/820,944 is a continuation of application No. PCT/CN2021/096742, filed on May 28, 2021.
Prior Publication US 2022/0407115 A1, Dec. 22, 2022
Int. Cl. H01M 4/505 (2010.01); H01M 4/525 (2010.01); H01M 10/0568 (2010.01); H01M 10/0525 (2010.01); H01M 10/0567 (2010.01); H01M 4/02 (2006.01)
CPC H01M 10/0568 (2013.01) [H01M 10/0525 (2013.01); H01M 10/0567 (2013.01); H01M 4/505 (2013.01); H01M 4/525 (2013.01); H01M 2004/028 (2013.01); H01M 2220/20 (2013.01); H01M 2300/0025 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A lithium-ion secondary battery, comprising:
a positive electrode sheet,
a negative electrode sheet,
a separator, and
an electrolyte solution,
wherein the positive electrode sheet comprises a positive electrode current collector, and a positive electrode material layer arranged on at least one surface of the positive electrode current collector, the positive electrode material layer comprising a positive electrode active material and carbon,
wherein
the electrolyte solution comprises a heat-stable salt and a low-impedance additive; and
a chemical formula of the heat-stable salt is (My+)x/yR1(SO2N−)xSO2R2, wherein the My+ is a metal ion, R1 and R2 are each independently a fluorine atom, an alkyl with 1-20 carbon atoms, a fluoroalkyl with 1-20 carbon atoms, or a fluoroalkoxy with 1-20 carton atoms, the x is 1, 2, or 3, the y is 1, 2, or 3; and a mass percent of the heat-stable salt in the electrolyte solution is set as k2%;
wherein a temperature rise coefficient of the positive electrode sheet k1=Cw/Mc, Cw is a positive electrode material load per unit area (mg/cm2) on the surface of any side of the positive electrode current collector on which the positive electrode material layer is loaded, and Mc is a carbon content (wt %) of the positive electrode material layer, 18≤Cw≤30, 1≤Mc≤7;
wherein the lithium-ion secondary battery satisfies 0.34≤k2/k1≤8; and
wherein the low-impedance additive is
a fluorosulfonate NSO3F,
wherein N is a metal ion of a salt.