储能科学与技术 ›› 2022, Vol. 11 ›› Issue (5): 1641-1649.doi: 10.19799/j.cnki.2095-4239.2021.0623

• 储能测试与评价 • 上一篇    下一篇

基于健康特征参数的CNN-LSTM&GRU组合锂电池SOH估计

戴彦文(), 于艾清   

  1. 上海电力大学电气工程学院,上海 200090
  • 收稿日期:2021-11-23 修回日期:2021-12-08 出版日期:2022-05-05 发布日期:2022-05-07
  • 通讯作者: 戴彦文 E-mail:1209742263@ qq.com
  • 作者简介:戴彦文(1997—),男,硕士研究生,主要研究方向为基于数据驱动的锂电池健康状态预测,E-mail:1209742263@ qq.com
  • 基金资助:
    上海绿色能源并网工程技术研究中心项目(13DZ2251900)

Combined CNN-LSTM and GRU based health feature parameters for lithium-ion batteries SOH estimation

Yanwen DAI(), Aiqing YU   

  1. College of Electrical Engineering, Shanghai University of Electric Power, Shanghai 200090, China
  • Received:2021-11-23 Revised:2021-12-08 Online:2022-05-05 Published:2022-05-07
  • Contact: Yanwen DAI E-mail:1209742263@ qq.com

摘要:

锂电池健康状态(state of health,SOH)是表征电池实际寿命的关键性参数。SOH不可直接测量,为进一步提升锂电池SOH估计的精度,提出一种基于健康特征参数的CNN-LSTM与GRU组合SOH估计方法。首先,从锂电池充电曲线中初步选取健康特征参数,并通过Spearman相关系数提取健康特征,具体包括恒定电流充电时长、恒定电压充电时长、恒定电流充电时长与恒定电压充电时长的比值以及恒定电流充电阶段温度曲线在时间上的积分与恒定电压充电阶段温度曲线在时间上的积分。其次,采用卷积神经网络(convolutional neural network,CNN)提取健康特征的局部特征,长短期神经网络(long short-term memory,LSTM)挖掘数据时间序列特征,构造CNN-LSTM融合神经网络。然后,将CNN-LSTM网络与门口循环单元(gated recurrent unit,GRU)通过自适应权重因子构成组合SOH估计模型。最后,以NASA锂电池数据集5号、6号、7号、18号电池参数为依据进行验证。实验结果表明,所提组合模型相比于CNN-LSTM、LSTM和GRU此类单一模型,平均绝对误差分别降低了71.8.%、62.4%、22.6%,均方根分别降低了84.1%、79.8%、44.3%。

关键词: 锂离子电池, 健康状态, 健康特征, CNN-LSTM, GRU

Abstract:

The State of Health (SOH) of lithium batteries is a key parameter to characterize the actual useful life. SOH is not directly measurable, and a combined CNN-LSTM and GRU estimation method based on health feature parameters is proposed to further improve the accuracy of SOH estimation. Firstly, the health feature parameters are initially selected from the Li-ion battery charging curve, and the health features are extracted by Spearman correlation coefficient. Secondly, Convolutional Neural Network (CNN) is used to extract local features of health features and Long Short-Term Memory (LSTM) to mine data time series features to construct a CNN-LSTM fusion neural network. Subsequently, the CNN-LSTM and the Gated Recurrent Unit (GRU) are combined to form a combined SOH estimation model by adaptive weighting factors. Finally, the validation is based on the NASA lithium battery dataset 5, 6, 7, and 18 battery parameters. The experimental results show that the estimation accuracy of the proposed combined model is better than that of the single model, and the estimation error is further reduced.

Key words: lithium-ion battery, state of health, health feature, CNN-LSTM, GRU

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