Efficient Determination and Analysis of Model-Based Optimal Charging Protocols to Minimize Li-Ion Battery Degradation

Abstract

Alternate charging protocols for lithium-ion batteries have been proposed to reduce aging and improve their lifetime.1 Physics-based models capture the mass and charge transport of lithium ions within the cell by solving their corresponding governing equations. Optimal charging profiles can be derived from physics-based models by controlling the cell's internal state and restricting phenomena that lead to cell degradation.Our previous efforts have shown that optimal charging profiles that restrict intercalation-induced stresses, lithium plating, and the SEI layer growth can be derived with reformulated physics-based models. 2 - 4 Deriving optimal charging profiles in real-time can be performed through the optimization of reduced-order models. This work demonstrates several optimal charging profiles derived from the Tanks-in-Series model 5 to minimize various degradation mechanisms. We test these profiles under several cycling protocols and analyze the effect of each mechanism on capacity loss. We have also shown cases of deriving optimal profiles during the cycling period to update the profile based on the aging trajectory of the cell. References A. Tomaszewska et al., eTransportation, 1, 100011 (2019).B. Suthar, V. Ramadesigan, S. De, R. D. Braatz, and V. R. Subramanian, Phys. Chem. Chem. Phys., 16, 277–287 (2014).B. Suthar, P. W. C. Northrop, R. D. Braatz, and V. R. Subramanian, J. Electrochem. Soc., 161, F3144–F3155 (2014).M. Pathak, D. Sonawane, S. Santhanagopalan, R. D. Braatz, and V. R. Subramanian, ECS Trans., 75, 51–75 (2017).A. Subramaniam et al., J. Electrochem. Soc., 167, 013534 (2020).