Abstract:

The development of power battery thermal runaway propagation passive suppression technology is of great significance to solve the spontaneous combustion accident of electric vehicles in the static state. Existing passive technologies are based on thermal barrier mechanisms, but the resulting large thermal resistance will seriously affect the daily battery thermal management performance. This paper proposes a pseudo-passive power battery heat removal system based on pump drive cooling and thermoelectric conversion, which converts part of the heat generated by the battery system into electrical energy to achieve pseudo-passive heat removal. On this basis, it is combined with a thermal barrier to reduce the thermal resistance required to block the spread of thermal runaway. This article develops a test prototype, conducts experiments to analyze the heat removal process under different battery system heating power conditions, and explores the impact of heating power distribution. When the heating power is reduced by 33%, the steady-state values of dissipation in the cooling process of the pump drive, heat absorption in the thermoelectric conversion process, and electric energy generation are reduced by 30%, 27%, and 15%, respectively. The research in this paper will help to significantly improve the safety performance of electric vehicles.

Key words: power battery, thermal safety, pseudo-passive, heat removed, thermodynamic process, thermodynamics, dynamics

摘要：

发展非主动式动力电池热失控传播抑制技术对解决电动汽车在静置状态下的自燃事故具有重要意义。现有的非主动式技术是基于热阻隔机制，但由此形成的大热阻将严重影响日常的电池热管理性能。本文提出基于泵驱冷却与热电转换的准被动式动力电池热移出系统，将电池系统部分产热量转换为电能以实现准被动式的热移出，在此基础上与热阻隔相结合以减小阻断热失控蔓延所需的热阻。本文研制试验样机，通过实验分析不同电池系统发热功率工况下的热移出过程，探究发热功率分布的影响。当发热功率减少33%时，泵驱冷却过程散热量、热电转换过程吸热量及产生电能的稳态值分别降低30%、27%和15%。本文研究有助于显著提升电动汽车安全性能。

关键词: 动力电池, 热安全, 准被动式, 热移出, 热力学过程, 热力学, 动态学