Silicon-based energy storage devices with fluorinated polymer containing electrolyte additives

1. An energy storage device comprising:

a first electrode and a second electrode, wherein at least one of the first electrode and the second electrode is a Si-based electrode;

a separator between the first electrode and the second electrode;

an electrolyte; and

at least one electrolyte additive comprising a compound selected from Formula (C):

wherein:

each R 5 and R 6 , is independently selected from the group consisting of —H, —OH, alkyl, alkenyl, nitrile, carboxyl, —Cl, —F, —CF 3 , and —OCF 3 ;

each A and B is

each optionally substituted by —F, —CF 3 , or —CH 3 ;

each Rb, and Rc is independently selected from the group consisting of —CF 3 ,

each optionally substituted by —F; and

each q and r is independently selected from an integer from 1-5.

2. The energy storage device of claim 1 , wherein the second electrode is a Si-dominant electrode.

3. The energy storage device of claim 1 , wherein the second electrode comprises a self-supporting composite material film.

4. The energy storage device of claim 3 , wherein the composite material film comprises:

greater than 0% and less than about 90% by weight of silicon particles, and

greater than 0% and less than about 90% by weight of one or more types of carbon phases, wherein at least one of the one or more types of carbon phases is a substantially continuous phase that holds the composite material film together such that the silicon particles are distributed throughout the composite material film.

5. The energy storage device of claim 1 , wherein the electrolyte further comprises fluoroethylene carbonate (FEC).

6. The energy storage device of claim 5 , wherein the electrolyte is substantially free of non-fluorine containing cyclic carbonate.