Long charging time is one of the technical barriers that should be overcome for the wide acceptance of electric vehicles (EVs) in the market. The charging time can be simply reduced by an increased charging current that adversely reduces lifespan and deteriorates the safety of batteries. Therefore, the design of an appropriate charging protocol is a challenging issue. We have developed a fast charging method based on a reduced order electrochemical life model (ROM) considering side reactions and lithium plating. Among different fast charging profiles, the negative pulse (NP) charging method is selected. The pulse discharging current between high charging currents can promote lithium stripping so that lithium ions can be recovered from the plated lithium. The fast charging currents are optimized using a nonlinear model predictive control (NMPC) algorithm. The objectives are set to reduce the charging time with minimized degradation speed. Multiple constraints are considered in NMPC such as state of charge, cutoff voltage, side reaction rate, anode potential, and ion concentrations. The proposed fast charging algorithm is tested in real-time using a Battery-In-the-Loop (BIL) system. The results have shown that the charging time can be reduced while degradation rate can be maintained compared with the normal charging method. Reference [1] Yin Y., Bi Y., Hu Y., Choe, S. Y. (2021). Optimal Fast Charging Method for a Large-Format Lithium-Ion Battery Based on Nonlinear Model Predictive Control and Reduced Order Electrochemical Model. Journal of The Electrochemical Society, 167, 160559 [2] Yin Y., and Choe, S. Y. (2020). Actively temperature controlled health-aware fast charging method for lithium-ion battery using nonlinear model predictive control. Applied Energy, 271, 115232.[3] Song M., Choi M., and Choe, S. Y. (2023). Start-Up Charging Strategy for a Large-Format NMCA/Graphite Pouch Cell from Subzero Temperature Using an Electrochemical, Thermal, and Mechanical Life Model. Journal of The Electrochemical Society, 170, 060533[4] Song M., and Choe, S. Y. (2019). Fast and safe charging method suppressing side reaction and lithium deposition reaction in lithium ion battery. Journal of Power Sources, 436, 226835
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