Health conscious fast charging of Li-ion batteries via a single particle model with aging mechanisms

Battery fast charging is one of the most significant and difficult techniques that affects the acceptance of the electric vehicles. Due to the complex electrochemical reactions, fast recharge could affect the battery functionality and accelerate its aging processes. The accelerated aging process during fast charging can dramatically reduce cell lifetime, impact cell safety, and must be avoided. In this paper, we propose a health conscious fast charging framework with the aim of simultaneously reducing the charge duration and the battery degradation. This paper presents an electrolyte enhanced single particle model with degradation mechanisms. A multi-objective optimal control problem is formulated. Dynamic programming (DP) technique is employed to find the optimal charging strategies. Charging time and battery degradation are traded off and optimized. Strategies for fast charging (minimum time) and health conscious fast charging are examined and compared. Multiple experiments are carried out to compare the charge time and capacity fade between fast charging strategy, traditional CC/CV protocol, and health conscious fast charging strategy. The results demonstrate that the health conscious fast charging strategy is able to significantly reduce the charging time without sacrificing battery health.