Energy Storage Science and Technology ›› 2025, Vol. 14 ›› Issue (2): 799-811.doi: 10.19799/j.cnki.2095-4239.2024.0808

• Energy Storage Test: Methods and Evaluation • Previous Articles     Next Articles

A parallel multi cale-featured fusion model for state-of-health estimation of lithium-ion batteries based on relaxation voltage

Hairui WANG1(), Changyu XU1, Guifu ZHU2(), Xiaojian HOU1   

  1. 1.School of Information Engineering And Automation, Kunming University of Science and Technology
    2.Information Technology Construction Management Center, Kunming University of Science and Technology, Kunming 650500, Yunnan, China
  • Received:2024-08-31 Revised:2024-11-05 Online:2025-02-28 Published:2025-03-18
  • Contact: Guifu ZHU E-mail:1035248443@qq.com;zhuguifu@kust.edu.cn

Abstract:

The estimation of state-of-health (SOH) in lithium-ion batteries is crucial for ensuring the reliability and safety of energy storage systems. However, existing SOH estimation methods are limited by single-feature extraction and dependency on fixed charge-discharge conditions, which hinders adaptability to dynamic operational environments. To address these challenges, we propose an SOH estimation approach based on relaxation voltage, integrating a parallel multiscale feature fusion convolution model (MSFFCM) with XGBoost. The MSFFCM model leverages multilayer stacked convolutional modules to extract deep features from relaxation voltage data while utilizing a parallel multiscale attention mechanism to enhance the capture of multiscale features. These features are then fused with statistical features to improve the model's feature extraction and integration capabilities. Bayesian optimization is applied to the XGBoost model for parameter tuning, enabling high-accuracy SOH estimation based on multi-source fused features. Validation experiments were conducted on datasets from two commercial 18650 lithium-ion battery types under varied temperature and charge-discharge strategies. Results indicate that the proposed method achieves a root mean square error and mean absolute error of less than 0.5%, significantly outperforming conventional methods. This study provides an effective estimation tool for lithium-ion battery health management without reliance on specific charge-discharge conditions, demonstrating promising potential for complex real-world applications.

Key words: lithium-ion battery, state-of-health estimation, relaxation voltage, parallel multi-scale features, feature fusion

CLC Number: