Improved Method for State of Charge Estimation of Lithium Iron Phosphate Power Batteries

Abstract:

To resolve the problems that the initial state of charge (SOC) and the available capacity of batteries are difficult to estimate when using the Ah counting method, in this paper An improved SOC estimation method was proposed that combined with the open circuit voltage (OCV) method and Ah counting method based on the analysis and consideration of the battery available capacity variation caused by charge and discharge current, environment temperature and battery state of health (SOH). The precision of the proposed method was validated by using Federal Urban Driving Schedule (FUDS) test of a Lithium iron phosphate (LiFePO4) power battery. The SOC estimate error using the proposed method relative to a discharge test was better than the Ah counting method.

• Periodical: Advanced Materials Research (Volumes 712-715)
• Pages: 1956-1959
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.712-715.1956
• Online since: June 2013
• Authors: Ming Li, Yang Jiang, Jian Zhong Zheng, Xiao Xiao Peng
• Keywords: Improved, Lithium Iron Phosphate, Power Battery, State of Charge (SOC)

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DOI: 10.2172/214312