Energy Storage Science and Technology ›› 2025, Vol. 14 ›› Issue (1): 358-369.doi: 10.19799/j.cnki.2095-4239.2024.0526

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

State of health estimation based on subtraction average based optimizer and bidirectional long and short term memory networks for lithium-ion batteries

Jianxuan LI(), Chen LIN, Zhongkai ZHOU()   

  1. School of automation, Qingdao University, Qingdao 266071, Shandong, China
  • Received:2024-06-12 Revised:2024-06-26 Online:2025-01-28 Published:2025-02-25
  • Contact: Zhongkai ZHOU E-mail:18946215411@163.com;zzkai@qdu.edu.cn

Abstract:

Accurate estimation of state of health (SOH) is crucial for ensuring the safe and reliable operation of lithium-ion batteries and extending their service life. To address the challenges posed by many health features that fail to characterize the aging mechanism of batteries and the inability to accurately track SOH trends under abnormal working conditions, this study introduces an SOH estimation approach that combines empirical models with data-driven techniques. The lithium-ion battery anode SEI film thickening mechanism is incorporated into Arrhenius' law to develop an empirical model. Parameters are identified using the least-squares method, and Spearman's correlation coefficients are calculated for each parameter and capacity. The results indicate strong correlations between these parameters and capacity decline, confirming their viability as reliable health indicators for estimating SOH. Furthermore, to address the issue of the bidirectional long and short term memory (BiLSTM) network having excessive parameters and being prone to overfitting, this study employs the subtraction average based optimizer (SABO) algorithm to optimize the hyperparameters of the BiLSTM and develop the SOH estimation model. The proposed approach is validated using experimental test data and data from the National Aeronautics and Space Administration data. In addition, the performance of the method is compared with the estimation results from three algorithms: long and short-term memory (LSTM) network, BiLSTM network, and BiLSTM network with Particle Swarm Optimization (PSO). The results reveal that the SABO-BiLSTM model achieves mean absolute percentage errors of 0.043%, 0.053%, 0.259%, and 0.230% for the SOH estimation of four batteries. These values represent reductions of 94.71%, 92.62%, 88.75%, and 90.13% compared to the LSTM model, reductions of 89.11%, 91.60%, 77.90%, and 76.41% compared to the BiLSTM model, and reductions of 58.65%, 58.91%, 65.37%, and 69.29% compared to the PSO-BiLSTM model.

Key words: lithium-ion batteries, Arrhenius law, subtraction average based optimizer, bidirectional long and short-term memory networks

CLC Number: