Electrolyte compositions for high voltage lithium-ion batteries

An electrochemical cell comprising an anode, a cathode, and a lithium-containing electrolyte contacting the anode and the cathode;

• the electrolyte comprising about 1 to 1.5 M LiPF6 in a liquid carrier comprising a carbonate ester containing about 0.25 to about 2 percent by weight of an unsaturated organoboron compound, based on the total weight of the liquid carrier;
• wherein the organoboron compound comprises two or three unsaturated hydrocarbon groups, each unsaturated hydrocarbon group being covalently bonded by a carbon atom thereof to a boron atom of the organoboron compound;
• wherein the unsaturated hydrocarbon groups are independently selected from vinyl, allyl, propargyl, substituted vinyl, substituted allyl, and substituted propargyl;
• the substituents of the substituted vinyl, allyl and propargyl groups independently comprise one or more of alkyl and phenyl;
• and the alkyl and phenyl groups optionally comprise one or more substituent selected from halogen, hydroxy, amino, alkoxy, and perfluoroalkoxy;
• and wherein the organoboron compound has the formula Z-X3, wherein Z is B, and each X independently is selected from vinyl, allyl, propargyl, substituted vinyl, substituted allyl, and substituted propargyl;
• the substituents of the substituted vinyl, allyl and propargyl groups independently comprise one or more of alkyl and phenyl;
• and the alkyl and phenyl groups optionally comprise one or more substituent selected from halogen, hydroxy, amino, alkoxy, and perfluoroalkoxy;
• and wherein the anode comprises graphite and the cathode comprises a lithium metal oxide material providing a cell voltage of about 4.5 V to 5V.