Search

• The FeS 2 cathode has successfully modified by Al 2 O 3 nanoparticles (FeS 2 @Al 2 O 3). • The modified FeS 2 @Al 2 O 3 increases the transport rate of lithium ions. • The good wettability of solid-liquid interface suppresses the overflow of electrolytes. • The thermal batteries using of FeS 2 @Al 2 O 3 cathode achieve better performance. Thermal batteries are widely employed as the primary reserve batteries due to their high energy density and long shelf lifespan. FeS 2 is the most studied and promising cathode material of thermal batteries at present because of its abundant stock and superior electrochemical performance. However, the FeS 2 cathode is limited by low discharge capacity, big polarization, and security issues during discharge process. Herein, the improved electrochemical performance is achieved by increasing the interface wettability between cathode and electrolyte, in which the FeS 2 cathode has modified by Al 2 O 3 (FeS 2 @Al 2 O 3) nanoparticles. The good wettability of the solid-liquid interface suppresses the overflow of electrolytes, and the discharge capacity of thermal batteries by using FeS 2 @Al 2 O 3 cathode is 341.3 mAh·g−1, which is higher than that of pure FeS 2 cathode (319.7 mAh·g−1). Significantly, this work provides a novel idea for modifying cathode material for comprehensive performance and safe thermal batteries in practical engineering applications. [ABSTRACT FROM AUTHOR]