Thermal problems in batteries are directly linked to abnormal temperature variations in batteries. Consequently, it is possible to convert the prognosis of battery thermal failure into an issue of forecasting temperature. A precise model can be used to estimate battery temperature in the future.
Abnormal battery temperature can result in decreased battery performance, shortened lifespan, safety hazards such as fire or explosion, potential system faults, and unstable operation. Remedies include cool-down treatments, system resets, overhaul and maintenance, software updates, and safe energy discharge. 2.3.1. Cooling system fault
Battery temperature abnormalities mainly included excessive temperature and rapid temperature rise. The dangers of high temperatures, as detailed in the previous discussion, include accelerated battery capacity decay, power loss, structural dissolution, electrolyte decomposition, and the potential for thermal runaway.
Some researchers have investigated the thermal stability of aged batteries under different abusive temperature conditions. Zhang et al. found significant similarities in the thermal safety evolution and degradation mechanisms of lithium-ion batteries during high-temperature cycling and calendar aging.
Unlike the thermal runaway behavior changes observed in batteries aged under high temperatures—where aged batteries exhibit delayed thermal runaway compared to new batteries—those aged under low temperatures show worse thermal runaway behavior, with more severe temperature rises and mass loss .
When the battery temperature exceeds the normal operating range, it accelerates the degradation of the battery's capacity and causes significant power loss. This thermal stress affects the electrochemical stability of the battery, leading to a reduction in its service life.