Advances in Thermal Battery Anodes

Thermal batteries are employed in virtually every strategic defense and tactical weapon system. As systems capabilities continue to increase, future thermal batteries will be required to deliver higher power and energy in packages smaller and lighter than those available with baseline lithium-silicon (LiSi) / FeS2 technology. Although ENSER’s proprietary LiSi / cobalt disulfide (CoS2) system provides a 50 – 80% increase in specific energy and is now employed in numerous next-generation systems, during the Phase I effort several new anode materials were identified which, combined with improved cathode materials under development as part of a separate R&D effort, offer the potential to substantially increase specific energy over the state-of-the-art LiSi / CoS2 system. Three candidate anode materials identified in Phase I, include: (1) a new binary LiX system, (2) LiSi alloy containing up to 50% lithium and (3) a novel ternary lithium system. Single-cell testing validated improved specific energy and specific capacity performance, and one new anode / new cathode combination validated that a 50% increase in specific energy over state-of-the-art LiSi / CoS2 was achievable. Phase II efforts will focus on selecting and optimizing the most viable anode candidates and validating improved performance in full-scale thermal batteries.