Advanced electrolyte for high voltage lithium-ion batteries

A lithium ion battery comprising:

• a cathode having a voltage of greater than 4.1 V v. Li/Li+ and an aluminum or stainless steel current collector;
• an anode;
• a separator;
• and
• an electrolyte comprising:
• a first salt that is a lithium sulfonylimide, a lithium sulfonate, a lithium sulfonylmethide, or a mixture of any two or more thereof, and the first salt is present in the electrolyte from about 0.1 M to about 2 M;
• an aprotic solvent;
• and
• a second salt which suppresses corrosion of the aluminum or stainless steel current collector;
• wherein:
• the second salt is present in the electrolyte from about 0.1 wt % to about 10 wt %;
• and
• the second salt is a compound of Formula I, II, or III:
• R1 is alkyl, alkenyl, or alkynyl;
• R2 is alkyl, alkenyl, or alkynyl;
• or R1 and R2 may join together to form a ring with the boron and oxygen atoms to which they are attached;
• R3 is F, Cl, Br, I, alkyl, or O-alkyl;
• R4 is F, Cl, Br, I, alkyl, or O-alkyl;
• or R3 and R4 may join together to form a ring with the boron atom to which they are attached;
• R5 is H, alkyl, alkenyl, alkynyl, or O-alkyl;
• and
• R6 is H, alkyl, alkenyl, or alkynyl.