With the popularity of electric vehicles and climate change, it has become a typical scene to charge lithium-ion batteries (LIBs) at low temperatures at a high rate. Low temperature and high-rate charge and discharge would change the performance and then affect temperature rises, heat production and thermal runaway (TR) characteristics. This study tests the temperature rises of aging 18650 LIBs at various ambient temperatures and charge and discharge rates. The entropy and enthalpy changes of the batteries are computed based on the entropy coefficients, and subsequently, the heat productions of the batteries are computed. The TR test is carried out to explore the influence of rapid aging at low temperature environment on the thermal safety of LIBs. In this work, the heat generation mechanism and thermal runaway characteristics of lithium-ion batteries after low-temperature and high-rate cyclic aging are introduced in detail, aiming to provide a reference for the process safe design and application of lithium-ion batteries at low-temperature and fast charging scenarios.

中文翻译：

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低温高倍率循环老化对锂离子电池热特性及安全性的影响


随着电动汽车的普及和气候变化，低温高倍率对锂离子电池（LIB）充电已成为典型场景。低温和高倍率充放电会改变性能，进而影响温升、产热和热失控（TR）特性。本研究测试了老化 18650 LIB 在不同环境温度和充放电速率下的温升。根据熵系数计算电池的熵变和焓变，随后计算电池的产热量。通过TR测试来探究低温环境下快速老化对锂离子电池热安全性的影响。该工作详细介绍了锂离子电池低温高倍率循环老化后的发热机理和热失控特性，旨在为锂离子电池的工艺安全设计和应用提供参考。低温快充场景。