BATTERY

A battery includes: a housing having a cavity; a battery cell arranged in the cavity, the battery cell including a positive electrode plate, a negative electrode plate, and a separator; and an electrolyte solution filled in the battery cell including fluoroethylene carbonate. A width of the separator is greater than that of the positive and the negative electrode plate. The battery satisfies following relationship: C≥B/20A+1, where a content of fluoroethylene carbonate in the electrolyte solution is C %, A represents a distance between an edge of the separator and that of an electrode plate on the same side, and B represents a height of the cavity. When the foregoing relationship is satisfied, deterioration of performance of the battery cell caused by insufficient electrolyte solution may be alleviated, thereby improving a value of a self-discharge coefficient k and cycling performance of the battery.