Energy Storage Science and Technology ›› 2022, Vol. 11 ›› Issue (1): 228-239.doi: 10.19799/j.cnki.2095-4239.2021.0373

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

Lithium-ion battery model based on sliding window and long short term memory neural network

Shaofeng ZHANG1, Qingyong ZHANG1(), Yesen YANG2, Yixin SU1, Binyu XIONG1   

  1. 1.School of Automation, Wuhan University of Technology, Wuhan 430072, Hubei, China
    2.School of Electrical and Electronic Engineering (EEE), Nanyang Technological University, Singapore 639798
  • Received:2021-07-26 Revised:2021-08-19 Online:2022-01-05 Published:2022-01-10
  • Contact: Qingyong ZHANG E-mail:qyzhang@whut.edu.cn

Abstract:

This study proposes a lithium-ion battery model based on the sliding window and long short-term memory (LSTM) neural network to improve the model accuracy under complex working conditions. First, a lithium-ion battery model based on the LSTM neural network is established. Next, the basic structure of the neural network is determined. The time series feature extraction, feature fusion, and regression prediction are realized by combining the LSTM, vector splicer, and full connection layers. A sliding window input vector processing method is then proposed. The sliding window is advanced one time point at a time, and the data volume is limited by restricting the maximum number of letter elements within the time window. A computational margin is reserved for the parallel computation of the multiple LSTM layers and the deep hidden layers of the splicing and fully connected layers. Subsequently, the optimal selection of the depth of the recurrent network layer in the model is achieved. A training method using offline data set pre-training and online data parameter modification is proposed to solve the generalization problem under various complex working conditions. The model learns the common parts of the battery through the repetitive training of a large number of offline data sets. The network parameters are adjusted and used in the prediction by using a part of the online data. Finally, the datasets of the constant current/constant voltage, random current pulse, high-power pulse, and other working condition test profiles are applied for validation. The results show that the proposed modeling method can accurately predict the battery's output voltage and state of charge.

Key words: lithium-ion battery, battery model, neural network, long short term memory, feature extraction, sliding window

CLC Number: