Preparation method of organic electrolyte capable of improving heat stability of lithium-ion battery

The invention relates to a preparation method of an organic electrolyte capable of improving heat stability of a lithium-ion battery. The method comprises the following steps: (1) mixing two or more organic solvents at a room temperature at equal mass ratio after removing impurities, so as to obtain a mixed solvent; (2) lastingly stirring the mixed solvent and adding various lithium salts with different contents to obtain a series of electrolytes without an additive; and (3) adding a flame-retardant additive and other functional additives to the electrolytes without the additive, so as to obtain the lithium-ion battery electrolyte with relatively good heat stability. According to the preparation method, the heat stability of the electrolyte can be improved; the safety performance and the cycle performance of the electrolyte at a high temperature can be improved; prolonging of the cycle lifetime and the storage lifetime of the lithium-ion battery is facilitated; and the method is simple in technique, low in cost, suitable for industrial production, and relatively wide in application prospect.