Lithium plating induced volume expansion overshoot of lithium-ion batteries: Experimental analysis and modeling

Under extreme charging conditions such as fast-charging and low-temperature charging, lithium-ion batteries suffer from volume expansion overshoot, i.e. battery volume expansion rapidly exceeds the maximal value during normal charging and falls to a steady value. Battery volume expansion overshoot can result in severe stress within module/pack and threaten battery safety. Though lithium plating has been reported as a possible cause of battery expansion overshoot, the quantitative relationship between the expansion overshoot and lithium plating remains elusive. In this paper, the correlation between the volume expansion overshoot and the lithium plating is firstly demonstrated through a series of non-destructive and post-mortem analyses. Differential analyses of the battery voltage and expansion ratio profiles demonstrate the concurrence of the expansion overshoot and the lithium plating, which is further validated through cross-section scanning electron microscopy. Furthermore, a battery volume expansion model is established to reproduce the expansion overshoot during charging process, for the first time. The simulation results further confirm that lithium plating is the root cause of the expansion overshoot. Based on the model, a linear relationship between the volume expansion overshoot and the amount of plated lithium is derived, which can be applied for quantitative detection of lithium plating in practical application.