A detailed experimental investigation on the critical external heat leading to the failure of lithium-ion (Li-ion) batteries was conducted using an Accelerating Rate Calorimeter (ARC) at the National Institute for Occupational Safety and Health (NIOSH). Several types of commercial Li-ion batteries were selected for the study, including an iron phosphate Li-ion battery (LFP), a lithium-titanate battery (LTO), and a lithium-nickel-manganese-cobalt-oxide battery (NMC). Each battery was placed in a specially designed sealed steel canister and heated in the ARC. Battery voltage throughout the test was monitored and used to indicate the time to a battery failure. Three thermocouples, one attached to the battery surface, one measuring air temperature inside the canister, and one attached to the canister’s internal surface, were used to record temperature changes during the heating tests. Different thermal behaviors were observed for the various battery types. An analytical model was developed to estimate the total external heat received by the battery using the measured temperatures. Experimental data ranked the batteries tested in terms of the heat to failure as: LFP 26,650 (11 kJ) > LFP 18650 (4.3 kJ) > NMC 18650 MH1 (3.6 kJ) ≈ LTO 18650 (3.6 kJ) > NMC 18650 HG2 (3 kJ). Total heat normalized to the battery nominal energy capacity was also calculated and ranked as: LTO 18650 ≈ LFP 26650 ≈ LFP 18650 > NMC 18650 MH1 ≈ NMC 18650 HG2. The test and analysis method developed can be extended to other types of batteries with a cylindrical shape. Results from this work provide insights to the thermal safety of Li-ion batteries and can help enhance battery thermal design and management.

美国国家职业安全与健康研究所 (NIOSH) 使用加速量热仪 (ARC) 对导致锂离子 (Li-ion) 电池故障的临界外部热量进行了详细的实验研究。研究选择了几种类型的商用锂离子电池，包括磷酸铁锂离子电池 (LFP)、钛酸锂电池 (LTO) 和锂镍锰钴氧化物电池 (NMC) . 每个电池都放置在一个专门设计的密封钢罐中，并在 ARC 中加热。监测整个测试过程中的电池电压并用于指示电池失效的时间。三个热电偶，一个连接到电池表面，一个测量罐内的空气温度，一个连接到罐的内表面，用于记录加热测试期间的温度变化。对于各种电池类型，观察到不同的热行为。开发了一个分析模型，以使用测量的温度来估计电池接收到的总外部热量。实验数据根据失效热对测试的电池进行排序：LFP 26,650 (11 kJ) > LFP 18650 (4.3 kJ) > NMC 18650 MH1 (3.6 kJ) ≈ LTO 18650 (3.6 kJ) > NMC 18650 HG2 (3 kJ) ）。还计算了归一化为电池标称能量容量的总热量，并将其排序为：LTO 18650 ≈ LFP 26650 ≈ LFP 18650 > NMC 18650 MH1 ≈ NMC 18650 HG2。开发的测试和分析方法可以扩展到其他类型的圆柱形电池。