An Adaptive Rapid Charging Method for Lithium-Ion Batteries with Compensating Cell Degradation Behavior

Abstract

Recent developments in high-density lithium-ion battery technologies have greatly expanded the electric vehicle (EV) market. Due to the fact that the rapid charging of an EV battery pack while maintaining a suitable cell cycle life is necessary for further growth of the EV market, we herein propose an innovative adaptive rapid charging pattern that minimizes cell degradation and reflects the degradation characteristics. This technology is advantageous in that cells can be developed by analyzing the charging characteristics in the latter stages of cell development of the rapid charging pattern, while also considering the complexity and heterogeneity of the manufacturing process. Furthermore, the battery charging pattern is optimized and controlled in real-time by reflecting the characteristics of the battery module and pack degradation as the cycle number is increased. More specifically, we present a preliminary study that simplifies the implementation of the new optimization pattern to improve the cell cycle life by over 45% in comparison to conventional fast charging patterns, and to address the drop in capacity in the latter half of cell life during rapid charging.