The aging process of lithium-ion batteries could be divided into two stages dominated by solid electrolyte interphase(SEI)growth and lithium plating mechanism.In order to quickly and accurately predict the aging process of lithium-ion batteries and identify the turning points of the two-stage aging process,an empirical model of the two-stage aging process based on electrochemical process model was established.Aiming at the aging process of Li(NiMnCo)O2 battery,the two-stage aging data under different parameter conditions were obtained based on the two-stage electrochemical process model.The two-stage empirical model of lithium-ion batteries under different conditions was obtained using a two-step nonlinear fitting method,and the empirical model was verified and compared with the traditional semi-empirical model.The results show that the empirical model of the battery aging process established in this work can effectively predict the two-stage aging process under different parameter conditions and is better than the traditional semi-empirical model particularly in the accelerated aging stage.
关键词
锂离子电池/容量衰退/循环寿命/转折点/两阶段经验模型
Key words
lithium-ion battery/capacity fade/cycle life/knee point/two-stage empirical model
维普
万方数据