Lithium ion cells are one of the most promising solutions for energy storage. However, inevitable aging during the actual application will influence its thermal safety. This work intends to study the effect of aging on thermal behaviors of cells under external heating abuse. It was clearly shown that both fresh and aged cells were revealed to undergo thermal runaway and be ignited to fire. The venting flow was characterized firstly by a laser visualization technique, and the different structures in the presence of venting were discussed. After aging, the onset temperature of thermal runaway increased, while the temperature rise rate and maximum surface temperature decreased. Besides, the flame temperature as well as flame shape and flame height, were analyzed. The aged cells gave a forked flame with lower maximum flame temperature and flame height than fresh cells. The total mass loss of aged cells was less than that of fresh cells. Note that the aging way also affected the thermal stability of cells. These results indicate that the aged cells have a lower hazard of safety in current study. However, aging condition and thermal stability of both on cell and material level deserve to be studied in future work.

锂离子电池是最有前途的储能解决方案之一。但是，实际应用中不可避免的老化会影响其热安全性。这项工作旨在研究在外部加热滥用下老化对细胞热行为的影响。清楚地表明，新鲜的和老化的电池都被发现经历热失控并被点燃燃烧。首先通过激光可视化技术表征了排气流，并讨论了存在排气时的不同结构。老化后，热失控的起始温度升高，而升温速率和最高表面温度降低。此外，分析了火焰温度以及火焰形状和高度。老化的电池产生的叉形火焰的最大火焰温度和火焰高度低于新鲜电池。衰老细胞的总质量损失小于新鲜细胞。请注意，老化方式也会影响电池的热稳定性。这些结果表明，在当前研究中，老化的细胞具有较低的安全隐患。但是，在电池和材料层面的老化条件和热稳定性都值得在未来的工作中进行研究。