Plating energy as a universal descriptor to classify accelerated cell failure under operational extremes
Sobana Perumaram Rangarajan, Yevgen Barsukov, Partha P. Mukherjee
Abstract
Lithium plating is an anode-centric degradation process occurring in lithium-ion batteries resulting in irreversible capacity loss and cell failure. Temperature plays a critical role in improving the kinetics and transport, reducing lithium plating propensity. This study quantitively probes the evolution of plating with aging under temperature extremes in commercial Li-ion cells. Plating energy is proposed as a unique descriptor to quantify the extent of lithium plating and state of the electrode using operando analytics at any operating condition. Cells operated at temperature extrema (high/low) experience rapid capacity fade accompanied by a significant rise in anode impedance and exhibit plating energies greater than 1 Wh. Unfavorable intercalation kinetics at low temperatures and favorable solid electrolyte interphase (SEI) kinetics at high temperatures exacerbate anode impedance. These kinetically disparate manifestations on anode impedance adversely impact the interfacial overpotential and reversibility of plating, resulting in localized deposits and preferential stripping, ultimately promoting cell failure.