ELECTROLYTE FOR USE IN SECONDARY LITHIUM BATTERIES WITH NICKEL-RICH CATHODE MATERIALS

An electrolyte for use in a secondary lithium battery having a nickel-rich cathode material includes lithium bis(fluorosulfonyl)imide, a solvent system including a first solvent and a fluorinated cyclic ether having a molecular weight greater than 110 g/mol, and, optionally, an additive. The first solvent may be a carbonate, an ester, an ether, a fluorinated carbonate, a fluorinated ester, a fluorinated ether, or any combination thereof. The solvent system comprises at least 50 wt % of the fluorinated cyclic ether.