Lithium ion battery

Abstract

The application relates to the technical field of lithium ion batteries and discloses a lithium ion battery. The lithium ion battery comprises a positive electrode, a negative electrode, a separator arranged between the positive electrode and negative electrode, and a non-aqueous electrolyte; an active material of the positive electrode comprises LiFePO4, the non-aqueous electrolyte comprises an organic solvent, a lithium salt, vinylene carbonate and a compound represented by Formula (1), wherein R1 is one or more of chain, cyclic and aromatic group with 2-20 carbon atoms, and a compacted density of the positive electrode material is more than 2 g/cm3. The lithium ion battery provided by the application may obviously improve the cycle and storage performances at high temperature, greatly improve the capacity retention rate and capacity recovery rate of battery, obviously reduce the thickness expansion rate after high-temperature storage, and meanwhile, greatly reduce the precipitation of iron ions.

Dependencies are inferred from the claim text.