A novel practical state of charge estimation method: an adaptive improved ampere‐hour method based on composite correction factor.

Xiong, Xin; Wang, Shun?Li; Fernandez, Carlos; Yu, Chun?Mei; Zou, Chuan?Yun; Jiang, Cong

Abstract

The research of the real-time state of charge (SOC) estimation method for lithium-ion battery is developing towards the trend of model diversification and algorithm complexity. However, due to the limitation of computing ability in the actual battery management system, the traditional ampere-hour (Ah) method is still widely used. First, temperature, charge-discharge current, and battery aging are considered as the main factors, which affect the estimation accuracy of the Ah method under the condition that detection accuracy of the current sensor is determined. Second, the relationship between the SOC and battery open-circuit voltage at different temperatures is analyzed, which is used to modify the initial SOC. Third, the influence mechanism of main factors on the effect of the Ah method is analyzed, and proposes a capacity composite correction factor to reflect the influence of charge-discharge efficiency, coulomb efficiency, and battery aging comprehensively, and then update its value in real-time. Lastly, the adaptive improved Ah formula and the complete SOC estimation model is designed, and the estimation effect of this model is verified by comparing with other SOC estimation methods in the experiment of dynamic cycle test. The results show that the estimation error of the adaptive improved method is less than 2% under two comprehensive working conditions, while the error of the traditional method is 5% to 10%, and compared with an extended kalman filter algorithm, it also gets a better SOC estimation performance, which proves that this method is scientific and effective.

Citation

XIONG, X., WANG, S.-L., FERNANDEZ, C., YU, C.-M., ZOU, C.-Y. and JIANG, C. 2020. A novel practical state of charge estimation method: an adaptive improved ampere-hour method based on composite correction factor. International journal of energy research [online], 44(4), pages 11385-11404. Available from: https://doi.org/10.1002/er.5758

• Journal Article Type: Article
• Acceptance Date: Jun 14, 2020
• Online Publication Date: Aug 20, 2020
• Publication Date: Nov 30, 2020
• Deposit Date: Aug 21, 2020
• Publicly Available Date: Aug 21, 2021
• Journal: International journal of energy research
• Print ISSN: 0363-907X
• Electronic ISSN: 1099-114X
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 44
• Issue: 14
• Pages: 11385-11404
• DOI: https://doi.org/10.1002/er.5758
• Keywords: Lithium-ion battery; State of charge; Adaptive improved ampere-hour method; Composite correction factor
• Public URL: https://rgu-repository.worktribe.com/output/962049