Electrolyte of lithium ion battery and preparation method of electrolyte

The invention discloses an electrolyte of a lithium ion battery, the electrolyte comprises an organic solvent and a solute, the organic solvent is a mixed solution formed by mixing five components including ethylene carbonate, methyl ethyl carbonate, dimethyl carbonate, fluoroethylene carbonate and dimethyl sulfoxide; and the solute comprises a lithium salt and an ionic liquid, or comprises a lithium salt, an ionic liquid and lithium fluoride, and the ionic liquid is N-octyl pyridine tetrafluoroborate. The invention also discloses a preparation method of the electrolyte. The N-octylpyridine tetrafluoroborate is adopted as the ionic liquid, an SEI film can be effectively formed, but the conductivity of the electrolyte is reduced, so that the conductivity of the electrolyte is improved by adding the lithium fluoride, and the performance of the electrolyte is further improved. 本发明公开了一种锂离子电池的电解液，包括有机溶剂和溶质，有机溶剂是由碳酸乙烯酯、碳酸甲乙酯、碳酸二甲酯、氟代碳酸乙烯酯、二甲基亚砜共五种组分混合而成的混合溶液；溶质包括锂盐、离子液体共两种组分，或者是锂盐、离子液体、氟化锂三种组分，其中离子液体为N-辛基吡啶四氟硼酸盐。本发