A battery, such as a lithium-ion battery, comprises a first electrode, a second electrode, a molten salt electrolyte, and an electron collector, associated with the first electrode, the electron collector comprising an electrically conducting film. The battery further includes a protection layer separating the electron collector and the first electrode, the protection layer comprising a carbon-containing material. The electron collector may be an electrically conducting material such as aluminum, aluminum alloy, copper, nickel, other metal (such as alloys), conducting polymer, and the like. In one example, the protection layer is a graphite layer. In other examples, the protection layer may be a fullerene film, carbon nanotube film, or other carbon-containing material.