Elucidating Copper Dissolution Phenomenon in Li-Ion Cells under Overdischarge Extremes


Commercial lithium-ion batteries (LIB) often specify a voltage range for safe operation to prevent undesirable side reactions in the cell. Overdischarge is an abnormal condition that occurs when LIB discharges below the manufacturer's recommended lower voltage limit when connected in parallel-series configuration. While many studies have investigated the effects of overdischarge down to 0.0 V, few of them have focused on overdischarge below 0.0 V. Extreme overdischarge causes dissolution of the copper from the anode current collector and leads to severe capacity loss and deposition of metallic copper.