Investigation on dynamic equalisation performance of lithium battery pack management

Research output: Contribution to journalArticle

Authors

  • Jie Lv
  • Wenji Song
  • Shili Lin
  • Ziping Feng

Colleges, School and Institutes

External organisations

  • Guangzhou Institute of Energy Conversion of the Chinese Academy of Sciences

Abstract

Lithium batteries must be connected in series to achieve large capacity and high-power output. Battery management system (BMS), which is designed to protect battery pack from damage and increase battery life, is important in electrical power system. The present equalisation techniques have many disadvantages: The passive balancing wastes energy and generates heat, while active balancing is complex. This study proposes an intelligent BMS with dynamic equalisation (DBMS) which contains active and passive balancing circuit independently per cell. Experimental results indicate that DBMS can reduce the inconsistency among cells. Moreover, the DBMS can assist battery stack to store and release more energy. Besides, the battery stack with DBMS gives an energy efficiency of 96.5% which is 7.7% higher than that without balancing. In addition, the battery stack with DBMS can reduce the maximum state of charge difference of cells from 10.415% to 4.51% after three charge-discharge cycles. What is more, the DBMS is simple and can decrease the auxiliary power level and the system heat. Such a DBMS will help us to provide a high-performance battery pack.

Details

Original languageEnglish
Pages (from-to)388-394
Number of pages7
JournalIET Circuits, Devices and Systems
Volume11
Issue number4
Early online date15 Dec 2016
Publication statusPublished - 1 Jul 2017