The Impact of Temperature on the Performance and Reliability of Li/SOCl2 Batteries

The performance and reliability of lithium thionyl chloride (Li/SOCl2) batteries are significantly affected by temperature, but the reliability level and failure mechanisms of Li/SOCl2 batteries remain unclear. In this study, Weibull distribution statistics were used to infer the life expectancy of Li/SOCl2 batteries at different temperatures. Additionally, the battery failure mechanism was analyzed using electrochemical impedance spectroscopy (EIS). It is found that under the discharge condition of 7.5 kΩ load, the mean time between failures (MTBF) and reliable life of the battery decreased with increasing operating temperature. Under the discharge condition of 750 Ω load, the MTBF of the battery peaked at 60 °C. Furthermore, the influence of temperature on the voltage output characteristics of Li/SOCl2 batteries and the voltage hysteresis were analyzed. Both the battery output voltage and the hysteresis effect increased with rising temperature. This is because high temperature accelerates internal battery reactions, thus altering the formation process of the passivation film on the lithium metal negative electrode.