主管：中华人民共和国应急管理部
主办：应急管理部天津消防研究所
ISSN 1009-0029  CN 12-1311/TU
消防科学与技术

消防科学与技术 ›› 2026, Vol. 45 ›› Issue (5): 26-33.

• • 上一篇    下一篇

锂电池安全阀朝向对电动自行车火灾特性的影响

林晓晔, 李凯玲, 侯亚楠, 王永逸   

  1. （长安大学 地质工程与测绘学院，陕西 西安 710061）
  • 收稿日期:2025-10-21 修回日期:2026-01-27 出版日期:2026-05-15 发布日期:2026-05-15
  • 作者简介:林晓晔，长安大学地质工程与测绘学院硕士研究生，主要从事消防安全工程研究，陕西省西安市雁塔区雁塔路南段126号，710061。
  • 基金资助:
    国家自然科学基金青年科学基金项目（52504200）； 中国博士后特别资助基金项目（2025T180447）

Impact of safety vent orientation on fire characteristics in lithium-ion battery e-bikes

Lin Xiaoye, Li Kailing, Hou Yanan, Wang Yongyi   

  1. (School of Geological Engineering and Geomatics, Chang'an University, Xi'an Shaanxi 710061, China)
  • Received:2025-10-21 Revised:2026-01-27 Online:2026-05-15 Published:2026-05-15

摘要： 针对电动自行车锂电池火灾这一城市安全重要问题，通过全尺寸燃烧试验分析了安全阀朝向对火灾发展过程的影响。结果表明，2次试验中，电动自行车火灾整体均呈现“初期燃烧、射流火-稳定燃烧、衰减熄灭”3个阶段。射流火次数与电池数量密切相关，而射流火焰规模与其发生次序无显著关联。安全阀竖直朝向（试验A）会显著提升其正上方区域火焰温度，平均最高温度达181.8 ℃，较水平朝向（试验B）提高约16%，且整车呈现“先车后部、后车前部”的完全燃烧模式，车前部由射流火直接引燃；而试验B的火焰水平喷射距离最远达2.5 m，但火灾仅局限于车后部。此外，试验A的总热释放量约为试验B的1.71倍。研究证明安全阀朝向可显著影响锂电池电动自行车火灾蔓延特征与燃烧强度。

关键词: 电动自行车, 锂电池, 安全阀, 燃烧特性, 火灾危险性

Abstract: This study addresses the critical urban safety issue of lithium-ion battery fires in electric bicycles by analyzing the influence of safety vent orientation on fire development through full-scale burning tests. Results show that e-bike fires generally exhibit three distinct stages in both tests: initial combustion, jet fire followed by stable combustion, and decay leading to extinction. The number of jet fire incidents is closely related to the number of battery cells, whereas the scale of jet flames shows no significant correlation with their sequence of occurrence. When the safety vent is oriented vertically (Test A), the flame temperature directly above it is significantly increased, with an average peak temperature of 181.8 ℃， approximately 16% higher than that observed in the horizontal orientation (Test B). Moreover, the entire e-bike in Test A is fully burned in a "rear-first, then front" pattern, where the front section is directly ignited by a jet flame. In contrast, Test B produces a horizontal jet flame with a maximum projection distance of 2.5 m, but the fire remains confined to the rear section. Additionally, the total heat release rate in Test A is about 1.71 times that of Test B. The study confirms that safety vent orientation significantly influences both fire spread behavior and combustion intensity in lithium-ion battery e-bike fires.

Key words: electric bicycle, lithium-ion battery, safety vent, combustion characteristics, fire risk