High voltage electrolyte additives
Described herein are additives for use in electrolytes that provide a number of desirable characteristics when implemented within batteries, such as high capacity retention during battery cycling at high temperatures. In some embodiments, a high voltage electrolyte includes a base electrolyte and one or more polymer additives, which impart these desirable performance characteristics. The polymer additives can be homopolymers or copolymers.
1. An electrolyte formulation, comprising:
a lithium salt,
a non-aqueous solvent, and
a copolymer additive comprising a maleic anhydride monomer and an aromatic monomer, wherein the copolymer additive is represented by Formula (f):
wherein m is an integer greater than 1, n is an integer greater than 1, and the copolymer additive has a concentration no less than 0.1 weight percent relative to a total weight of the electrolyte formulation and no greater than 10 weight percent relative to the total weight of the electrolyte formulation.
2. The electrolyte formulation of claim 1 , wherein the copolymer additive has a concentration no less than 0.5 weight percent and no greater than 2 weight percent relative to the total weight of the electrolyte formulation.
3. The electrolyte formulation of claim 1 , wherein the copolymer additive has a molecular weight of about 9,500 g/mol.
4. A battery comprising:
an anode comprising an anode active material;
a cathode comprising a cathode active material; and
an electrolyte comprising a lithium salt, a non-aqueous solvent, and a copolymer additive comprising a maleic anhydride monomer and an aromatic monomer, wherein the copolymer additive is represented by Formula (f):
wherein m is an integer greater than 1, n is an integer greater than 1, and the copolymer additive has a concentration no less than 0.1 weight percent relative to a total weight of the electrolyte formulation and no greater than 10 weight percent relative to the total weight of the electrolyte formulation.
5. The battery of claim 4 wherein the cathode active material comprises nickel, manganese, and cobalt.
6. The battery of claim 4 wherein the anode active material comprises graphite.
7. The battery of claim 4 , wherein the copolymer additive has a concentration no less than 0.5 weight percent and no greater than 2 weight percent relative to the total weight of the electrolyte formulation.