An Optimal Strategy of Balancing for LiFePO₄ Battery in Battery Energy Storage System

Abstract:

Cell imbalance is one of the key factors that limit the capacity and power of battery energy storage systems (BESS), especially the large lithium-ion battery packs. To deal with the unbalancing problem, an effective balancing circuit is required, so is an optimal balancing strategy. In this paper, an optimal strategy for cells balancing has been presented. Contrary to the conventional balancing algorithms which base on instantaneous voltage or state-of-charge (SOC) no matter what the cause of imbalance is, the proposed strategy is targeted to different imbalance situations. Four cases of cell imbalance have been analyzed and the balancing effects of different algorithms are discussed. The simulation results show that the proposed strategy improves the performances of battery packs, including the usable capacity and maximum power.

• Periodical: Applied Mechanics and Materials (Volumes 341-342)
• Pages: 1286-1293
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.341-342.1286
• Online since: July 2013
• Authors: Bo Li, Dai Ming Yang, Jian Zheng Liu, Man Chen, Zhi Gang Lu
• Keywords: Balancing Strategy, Battery Energy Storage System (BESS), Imbalance Analysis, LiFePO4 Battery

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