High-rate electrolyte of lithium-ion battery

The invention discloses a high-rate electrolyte of a lithium-ion battery. The electrolyte is prepared from an organic solvent, a lithium salt and additives; the organic solvent is a mixture of ethylene carbonate, dimethyl carbonate and ethyl methyl carbonate; the lithium salt is a mixture of lithium hexafluorophosphate, lithium tetrafluoroborate and lithium bis(oxalate)borate; the additives are vinylene carbonate and 1,3,2-Dioxathiane 2-oxide. According to the high-rate electrolyte of the lithium-ion battery, by adopting compositions, with proper proportions, of the solvent and the lithium salt and the proper additives, the dissociation degree of the lithium salt in a solution and the migration rate of lithium ions can be increased, the electrolyte can form a passivation protection film which is good in stability and ionic conductivity on the negative electrode surface, and therefore the rate discharge characteristic of the lithium-ion battery is improved.