Analysis of the Cycle Life Characteristics of Lithium-Ion Batteries according to their Anode Density in High Rate Charging

Abstract

Recently, Li-ion batteries have become battery technologies ranging from electric vehicles to grid packing system. Although a lot of automakers are announcing electric forms with its products, range anxiety and the time required to charge the batteries are even now a frequent worry. Extreme fast charging, by aiming 20 minutes recharge time for 80% SOC, is composed to quicken mass market acceptance of electric vehicles currently. However, these goals not only inhibit Li deposition but also require good lifetime for offering a good performance. By changing the electrode density of anode in the whole NCM811/graphite lithium-ion battery, delaying cell degradation were attempted. This work was investigated using several methods such as XRD, XPS and SEM after cycle life test. Also, variations of charging protocol were often made to avoid mechanical stress condition when Li plating is possible by reducing heat generation. In addition, superficial film construction was not even after cycling in high rate charging and 1C discharging. This non-even modification more followed in active material delamination from the current collector because of the changes of charging protocol and electrode density of anode