Stratified Sorting Method of Battery Module Considering SOH in Echelon Utilization

To improve the efficiency of large-scale retired power battery (RPB) sorting in echelon utilization, and a stratified sorting method is proposed in the paper which takes battery module (BM) as object. Firstly, the correlation characteristic between the single battery and BM is built, and the main parameters of affecting the attenuation characteristic of the BM are defined. According to the consistency of the static initial parameters of the battery module, the first sorting is accomplished. Secondly, the characteristics correlation function between the single battery and the BM is established. The output characteristics of BM are calculated by using the equilibrium control method. Finally, the coupling relationship of the state of charge (SOC), depth of discharge, power characteristics and the state of health (SOH) of BM are established considering the SOH of BM comprehensively. The BM is sorted for the second time by using k-means clustering. The proposed sorting method is verified by simulation which effectively improves the accuracy of sorting and improves the battery's SOH.