Energy Storage Science and Technology ›› 2022, Vol. 11 ›› Issue (1): 221-227.doi: 10.19799/j.cnki.2095-4239.2021.0333

• Energy Storage Test: Methods and Evaluation • Previous Articles     Next Articles

Quantitative analysis of key battery performance parameters of aging lithium battery module

Zihan YUAN1(), Xiao YAN2,3(), Tao YANG1   

  1. 1.School of information science and engineering, Fudan University, Shanghai 200433, China, Shanghai 201600, China
    2.Hong Kong quantum Artificial Intelligence Laboratory, University of Hong Kong, Hong Kong 999077, China, Shanghai 201600, China
    3.Shanghai MeiKeSheng Energy Storage Technology Co. Ltd. , Shanghai 201600, China
  • Received:2021-07-12 Revised:2021-07-26 Online:2022-01-05 Published:2022-01-10
  • Contact: Xiao YAN E-mail:1113648654@qq.com;sean.x.yan@ms-battery.cn

Abstract:

The number of retired energy storage batteries is gradually increasing with the rapid development of the new energy electric vehicle industry. To evaluate, maintain, and utilize retired lithium batteries, this study proposes a quantitative analysis method for the key battery performance parameters of an aging lithium battery module that adopts the “zero time cost” rapid detection method without disassembly. The key battery parameters (kbps), including the internal resistance, relative charging time difference, and charging cut-off voltage, can be characterized at the single-cell level by only one charging datum. The abnormal cells can then be detected by a box diagram of these kbps. The rechargeable capacity of each monomer and the continuous discharge capacity at the discharge cut-off time are estimated and compared with the abnormal monomer based on the capacity increment curve. Accordingly, specific maintenance suggestions are put forward, including equalization or replacement, and the expected effect is given, that is, the effectiveness of maintenance measures can be evaluated before maintenance to avoid an invalid maintenance. Three experiments were performed herein, and the kbps at the cell level were quantitatively analyzed. In Experiment 1, only a replacement maintenance can be conducted because an abnormal kbp exists in the same cell. A capacity calculation estimated that the discharge capacity of the battery pack can be increased by 12.57% after maintenance. In Experiment 2, a balanced maintenance can be performed because an abnormal kbp exists in different cells. The capacity calculation also estimated that the discharge capacity of the whole module can be increased by 35.9% after maintenance. Lastly, in Experiment 3, no abnormal value was found in some kbps due to the small difference among the monomers; hence, no maintenance measures were needed.

Key words: aging battery module, quantification, performance parameters

CLC Number: