Modeling the electrochemical behaviors of charging Li-ion batteries with different initial electrolyte salt concentrations

Based on a 1D electrochemical model, a series of galvanostatic charge processes of lithium ion batteries with different initial electrolyte salt concentrations are simulated and investigated. In light of the simulation results, it is found that many electrochemical characters, including charge curve, end-of-charge salt concentration, anode potential, and reaction depth distribution, can all be affected by initial electrolyte salt concentration. Meanwhile, the lithium plating phenomenon commonly occurring during charge is studied with batteries of different salt concentrations during overcharge. A corresponding solution, changing the thickness ratio of anode to cathode, is proposed, which can also be used to extend the charging capacity. Overall, this study gives better understanding of the relevance between electrochemical behaviors of charging battery and initial electrolyte salt concentration, thus emphasizes the important role of electrolyte salt concentration in the performance and health of lithium ion battery. Copyright (C) 2016 John Wiley & Sons, Ltd.