大容量储能电芯热特性及热失控预警研究

Research on Thermal Characteristics and Thermal Runaway Early Warning for Large-Capacity Energy Storage Battery Cells

摘要: 研究热失控预警及电芯热特性对提高锂离子电池的热安全性具有重要意义。本文以大容量储能电芯为研究对象，首先对大容量储能电芯进行热特性研究，探讨了多种信号作为热失控预警信号的可行性。结果表明，与温度相比，利用膨胀力可以提前386 s检测到电池故障，提前202 s提供热失控预警。这表明在大容量储能电芯使用膨胀力仍然具有良好的可行性。此外，通过不同类型的信号的对比，发现膨胀力信号在大容量储能电芯的热失控预警中是优于其他类型的信号的。同时基于上述的实验数据开发出大容量储能电芯热失控预测模型，热失控起始时间误差小于1%，热失控最高温度误差小于3%。

Abstract: Investigating thermal runaway early warning and thermal characteristics of battery cells holds significant importance for enhancing the thermal safety of lithium-ion batteries. This study focuses on large-capacity energy storage battery cells, conducting comprehensive thermal characterization to evaluate the feasibility of multi-signal monitoring for thermal runaway prediction. The experimental results demonstrate that compared to temperature signals, expansion force monitoring enables 386 s earlier detection of battery failure and provides a 202 s advance warning for thermal runaway initiation, proving its superior applicability in large-capacity energy storage systems. Through comparative analysis of heterogeneous signals, the expansion force signal exhibits optimal responsiveness in capturing thermal runaway precursors. Furthermore, a predictive model for thermal runaway propagation was developed based on experimental datasets, achieving a prediction error of less than 1% in thermal runaway onset timing and maintaining under 3% deviation in maximum temperature forecasting.