The Sodium/Nickel Chloride Battery

Abstract Na–NiCl 2 thermal batteries have been developed for applications such as electric energy backup, energy storage, and automotive application. A typical Na–NiCl 2 battery consists of a molten sodium anode, a solid‐state electrolyte (β″‐alumina), and a secondary liquid electrolyte (NaAlCl 4 ) in the cathode side, with NiCl 2 as the active cathode materials. These systems, operating at high temperatures (about 270–350 °C), provide a battery completely independent of ambient temperature with high specific energy and high specific power. Special characteristics such as relatively low cost, long deep cycle life, long‐term cold‐storage life, abuse resistant, zero electrical self‐discharge, maintenance free, and safety place this technology as the best choice where environmentally strong conditions are present and other secondary battery systems fail.