Model-guided diagnosis and mitigation of lithium plating in lithium-ion batteries under subzero charging: Experimental validation and strategy evaluation

Lithium plating during low-temperature charging critically limits the safety, durability, and reliability of lithium-ion batteries, posing a major obstacle to their large-scale deployment in electric vehicles and energy storage systems in cold regions. This study integrates modeling and experimental approaches to investigate lithium plating in cylindrical LiCoO₂/graphite batteries under subzero charging conditions (−10 °C to −30 °C). By incorporating a lithium-plating side reaction into a simplified electrochemical–thermal model, the onset and progression of plating are predicted based on overpotential evolution. A combination of non-destructive (dV/dQ and Coulombic efficiency) and destructive (SEM and ICP) methods validates the model's accuracy and quantifies the extent of lithium deposition. Model-based strategy analysis further evaluates two mitigation routes—cell preheating and adjustment of the negative-to-positive (N/P) capacity ratio. The results demonstrate that preheating and N/P optimization both reduce lithium plating, but preheating is markedly more effective: at −10 °C and 1.0C, raising the N/P ratio from 1.08 to 1.2 decreases plating time from 90.3% to 43.0%, whereas preheating to 10 °C lowers it to 10.1%. The proposed framework accurately predicts lithium-plating behavior and provides practical guidance for safe, energy-efficient battery operation under extreme conditions. These findings contribute to the sustainable and secure utilization of electrochemical energy storage technologies in a low-carbon energy future.