Patent attributes
An energy storage device includes a first electrode and a second electrode, a separator between the first electrode and the second electrode, and an electrolyte in contact with the first electrode, the second electrode, and the separator. The electrolyte includes at least one of a fluorine-containing cyclic carbonate, a fluorine-containing linear carbonate, and a fluoroether. At least one of the first electrode and the second electrode includes a self-supporting composite material film. The composite material film has 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. At least one of the one or more types of carbon phases can be a substantially continuous phase that holds the composite material film together such that the silicon particles are distributed throughout the composite material film.