Current Status and Prospects of Research on Cathode Materials for Lithium-Based Thermal Batteries

As a result of their short activation time, high power density, and long storage life, thermal batteries have been widely used in various military applications. Important thermal battery characteristics, such as operation voltage, specific capacity, and power density, are determined by the properties of the electrode materials, especially the cathode materials. Therefore, one of the major challenges in advancing thermal batteries is the seeking of desirable cathode materials. Generally, cathodes used in thermal batteries are broadly classified into three main categories: metal oxides, metal sulfides, and metal halides. This review will introduce the current synthetic preparation methods, electrochemical performance, and working mechanisms of thermal battery cathode materials at home and abroad. For the metal oxide part, vanadium oxide, copper oxide, and some other metal oxide materials will be reviewed. Metal sulfides for thermal batteries discussed include iron sulfide, cobalt sulfide, nickel sulfide, and some other novel metal sulfide materials. Metal halides, especially fluorides and chlorides, will also be intensively discussed. We hope that this review will provide clear strategies and prospectives for future experimental studies and insight for theoretical studies on the development of thermal battery cathode materials.