Silicon-based energy storage devices with linear carbonate containing electrolyte additives
Electrolytes and electrolyte additives for energy storage devices comprising linear carbonate compounds.
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 and where the silicon is present as silicon particles;
a separator between the first electrode and the second electrode;
an electrolyte; and
at least one electrolyte additive comprising a compound selected from Formulae (A), (B), and (C):
wherein:
each R 1 and R 2 is independently selected from the group consisting of
and absent thereby leaving a negative charge; and
R is a C1-C3 alkyl;
wherein:
each R 1 and R 2 is independently selected from the group consisting of
and absent thereby leaving a negative charge; and
R is a C1-C3 alkyl;
and
wherein:
each R 1 and R 2 is independently selected from the group consisting of
and absent thereby leaving a negative charge;
R is a C1-C3 alkyl; and
X is selected from the group consisting of an alkylene optionally substituted by
or a chloroalkyl, a cycloalkylene, and a heteroalkylene with at least one —O—.
2. The energy storage device of claim 1 , wherein the second electrode is a Si-dominant electrode, where silicon is the majority of the active material used in the electrode by weight.
3. The energy storage device of claim 1 , wherein the second electrode comprises a self-supporting composite material.
4. The energy storage device of claim 3 , wherein the composite material 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 together such that the silicon particles are distributed throughout the composite material.
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 free of non-fluorine containing cyclic carbonate.