| abstract |
A lithium ion battery (5) and a device. The lithium ion battery (5) comprises an electrode component and an electrolyte. The electrode component comprises a positive electrode plate, a negative electrode plate, and a membrane. The positive electrode active material in the positive electrode plate comprises Li x1 Co y1 M 1-y1 O 2-z1 Q z1 , wherein 0.5≤x1≤1.2; 0.8≤y1<1.0; 0≤z1≤0.1; M is selected from one or more of Al, Ti, Zr, Y, and Mg; Q is selected from one or more of F, Cl, and S. The electrolyte comprises vinylene carbonate, fluoroethylene carbonate, 1,3-propanesultone, and an additive agent A. The additive agent A is a polynitrile six-membered nitrogen heterocyclic compound having a low oxidation potential. The lithium ion battery (5) has good cycle performance and storage performance, especially in high temperature and high voltage conditions. |