The invention relates to the field of 
lithium ion batteries, and discloses an 
electrolyte which comprises a high-temperature 
organic solvent, a positive and negative 
electrode protection additive andan 
electrolyte lithium salt, wherein the high-temperature 
organic solvent comprises the following components in parts by weight of 5-30 parts of 
ethylene carbonate, 5-30 parts of 
propylene carbonate,5-30 parts of 
diethyl carbonate, 5-50 parts of propyl 
propionate and 1-10 parts of 
fluorobenzene; the positive and negative 
electrode protection additive comprises the following components in parts byweight of 0.2 to 5 parts of 
ethylene sulfate, 0.2 to 5 parts of fluoroethylene 
carbonate, 0.2 to 5 parts of difluoroethylene 
carbonate, 0.2 to 5 parts of a dinitrile 
organic matter, 0.2 to 3 parts oflithium 
difluorophosphate, 0.2 to 5 parts of 
diethylene glycol dipropionitrile 
ether, 0.2 to 3 parts of 
lithium fluorosulfonyl 
imide, 0.1 to 2 parts of 1-propyl 
phosphoric anhydride, 0.5 to 20 partsof 1, 1, 2, 2-tetrafluoroethyl-2, 2, 3, 3-tetrafluoropropyl 
ether, 0.1 to 2 parts of lithium oxalyldifluoroborate and 0.1 to 1 part of 
methylene methanedisulfonate. The 
electrolyte is excellent in high-
temperature resistance, enables the 
lithium ion battery with 
high energy density to normally work at the temperature of 70 DEG C or above, and can keep the relatively better endurance.