Lithium Plating Detection and Intensity Estimation Using Current Pulsation

In situ detection and avoidance of lithium plating during battery charging is a key element to enable fast charging of Li-ion batteries. In this paper, a methodology is proposed to identify occurrence of lithium plating using the cell voltage during charging. The proposed method applies short interruptions, such as 5 seconds, to the constant current charging profile and monitors the cell behavior during the current cutoff period. It is found that, the voltage droop during the current cutoff behaves differently at high charging rates, when reversible plating happens on the anode, compared to low current charging conditions. The voltage droop is used to estimate a low frequency impedance for the cell which is found as a reliable indicator for the plating detection. Validated with anode potential measured using a reference electrode, the results indicate that lithium plating is successfully detected for two different chemistries using the proposed active diagnostics algorithm. In addition, it is found that the estimated impedance behavior is correlated to the severity of the lithium plating observed in the cell.