Self-discharge study of Li-alloy/FeS2 thermal cells

The capacities of Li-alloy/FeS₂ thermal batteries are influenced by the extent of self-discharge reactions that occur during operation. For some thermal battery applications involving open circuit (i.e., wet stand) conditions, this self-discharge can result in a significant loss in capacity. A study was undertaken to obtain a better understanding of the factors influencing the self-discharge of thermal cells, such as temperature, electrolyte composition, and processing of the catholyte (i.e., lithiation and fusion). The cells were discharged after prescribed times at open circuit under isothermal conditions and the capacity to a cutoff voltage was measured. Postmortem characterization of the cells was used to correlate the results of the electrochemical experiments. The results of the various tests are presented in detail