Lithium Ion Battery

In order to overcome the problems in existing lithium ion batteries having high compactness and high-specific-surface-area negative electrodes of serious side reactions of electrolytes and high gas production, the present invention provides a lithium ion battery, comprising a positive electrode, a negative electrode, and a non-aqueous electrolyte. The negative electrode comprises a negative electrode material layer, the compaction density of the negative electrode material layer is greater than or equal to 1.4 g/cm3, and the negative electrode material layer comprises a negative electrode active material, and the non-aqueous electrolyte comprises a solvent, an electrolyte salt, a vinylene carbonate, a fluoroethylene carbonate, and an unsaturated phosphate represented by structural formula 1, and the electrolyte salt comprises LiPF6 and LiFSI. The lithium ion battery provided by the present invention has good cycle performance, high and low temperature storage performance, and lithium precipitation resistance.