Abstract:

The detection and safety early warning method for the aging process of lithium-ion batteries using double-layer GeTe thermoelectric materials. This method capitalizes on the relationship between the temperature differential (ΔT) across the thermoelectric material and the thermoelectric induction signal, enabling precise identification of "irreversible reactions" at the microscopic level within the battery. During the early stages of thermal runaway, the thermoelectric sensor's response current can escalate to 183.7 μA/μm, approximately an order of magnitude higher than under standard operating conditions, thereby effectively mitigating the risk of abnormal aging and thermal runaway in lithium-ion battery energy storage systems. Additionally, the study delved into how external stress affects the sensitivity and reliability of these double-layer GeTe thermoelectric devices. It was discovered that their response signals exhibit a high degree of sensitivity to ΔT and temperature increments. Specifically, before the battery's temperature differential surpasses 60K, the sensor's thermoelectric response ratio increases by more than 1.2 times for every 10K change in temperature gradient. Moreover, even under the influence of curling strain, the strength of the thermal runaway early warning signal remains over five times stronger than under normal operating conditions, highlighting the devices' robust stress stability. The findings suggest that double-layer GeTe thermoelectric materials possess excellent thermoelectric sensing capabilities, sensitivity, and stability, making them a promising candidate for monitoring the aging process of energy storage lithium-ion batteries and for the early detection of thermal runaway incidents.

Key words: Energy storage battery, Early warning, Double-layer GeTe, Intelligent sensing