Typical abuse tolerance behavior in LiFePO4 batteries under lithium plating versus normal aging

Abstract

The tolerance of differentially aged batteries under typical abuse conditions plays a critical role in battery safety protection design. A multi-physics abuse testing platform integrating mechanical, electrical, and thermal stimuli was developed to investigate the abuse tolerance of lithium-plated and normally aged batteries, based on their external physical responses and irreversible chemical reactions. Novel evaluation metrics for crush-induced failure were first established, including rebound rate, total absorbed energy of plastic deformation, and frequency of soft short-circuit events. The thermal runaway evolution during heating abuse was systematically analyzed by dividing the process into three stages based on voltage drop and characteristic temperature thresholds. For overcharge abuse, incremental capacity (IC), differential voltage (DV), differential temperature (DT), and differential mechanical stress (DM) curves were employed to qualitatively evaluate lithium-ion loss and active material degradation. Ten mechanical–electrical–thermal indicators were proposed to comprehensively assess battery failure under various abuse scenarios. The results demonstrate that the mechanical stability of fresh, normally aged, and lithium-plated batteries sequentially decreases during crush testing (maximum failure displacement reduced by 8.6%). Thermal tolerance during heating abuse exhibits a negative correlation with state of health (SOH), with lithium-plated batteries showing the poorest performance (average venting time advanced by 26.8%). In overcharge abuse, venting time positively correlates with SOH, accompanied by a 34.9% surge in heat generation during the smoking phase. Integrated analysis of electrochemical–thermal stability and failure metrics reveals that lithium-plated batteries pose the highest safety risks across all abuse conditions, necessitating prioritized attention in intelligent battery management systems (BMS) for early risk warning and timely replacement. These findings provide critical insights for optimizing safety design and operational strategies of lithium-ion batteries in practical applications.