An Effective Equalization Based On Fuzzy Logic for Series Moduled Battery Strings

  • Shumei Zhang
  • Yishan Cai
  • Jiaxi Qiang
  • Lin Yang
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 216)


In the lithium-ion batteries for electric vehicle applications, the battery equalizer is required to enhance life time and guarantee safety. A simple technique that provides effective equalization in terms of battery voltage for a series string of battery cells is presented in this paper. The advantages of accurate equalization are very substantial and include reduced damage to battery cells in the stack and a dramatic increase in battery life. The main circuit technique of two-level DC/DC converters substantially simplifies the structure. Moreover, fuzzy logic equalizing algorithm effectively enhances the uniformity of batteries. The operational principles and design considerations of the proposed equalizer are presented, and equalization performance is verified by the prototype with 6 Ah lithium-ion batteries.


Electric vehicle Battery equalizer Two-level DC/DC converters Fuzzy logic equalizing algorithm Uniformity of batteries 


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Copyright information

© Springer-Verlag London 2013

Authors and Affiliations

  • Shumei Zhang
    • 1
  • Yishan Cai
    • 1
  • Jiaxi Qiang
    • 1
  • Lin Yang
    • 1
  1. 1.Institute of Automotive Electronic Technology Shanghai Jiao Tong UniversityShanghaiChina

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