Lithium-ion battery with long charged storage life and preparation method of lithium-ion battery

The invention discloses a lithium-ion battery with long charged storage life and a preparation method of the lithium-ion battery. An electrolyte additive is one or more of vinylethylene carbonate (VEC), vinylene carbonate (VC), ethylene sulfite (ES), fluoroethylene carbonate (FEC) and lithium carbonate (Li2CO3); and the formation system comprises the steps of (1) carrying out 0.1C constant-current charging to 4.1V, transferring into constant-voltage charging until cutoff current is 0.02C and carrying out 0.2C constant-current discharging to 3V; and (2) carrying out 0.2C constant-current charging to 4.1V and transferring into constant-voltage charging until the cutoff current is 0.02C. The lithium-ion battery prepared by the electrolyte additive and the formation system has relatively long charged storage life; the 0.5C-discharge capacity retention ratio is 91.67% after the battery with full charge is stored at a room temperature for one year and the irreversible capacity loss is 1.5%; the activated 3C-discharge capacity after storage for one year is 98.6% of that before storage; and the capacity retention ratio of 300 0.5C-charge and 1C-discharge 100% DOD cycles after storage for one year is 85.34%.