ELECTROLYTE ADDITIVE, BATTERY ELECTROLYTE AND APPLICATION THEREOF

An electrolyte additive, including a radical trapping agent, which includes at least one of a structural formula I and a structural formula II. The radical trapping agent of the provided structural formulas I-II can stably carry nitrogen free radicals or oxygen free radicals. Therefore, when used in the electrolyte, the electrolyte additive can consume harmful groups, such as CH· free radicals, acyl free radicals, and CHO· free radicals, generated during the charging and discharging process of the secondary battery, and can effectively inhibit the generation of active oxygen in the cathode additive of the secondary battery. In this way, the gas production phenomenon of the secondary battery during the charging and discharging process is effectively inhibited, the gas production volume is significantly reduced, and the volume expansion of the secondary battery is reduced, thereby effective improving the stability and safety of the charging and discharging of the secondary battery.