The thermal runaway of lithium-ion batteries under extreme coupled abuse conditions has seriously hindered the sustainable development of lithium-ion new energy vehicles. To reveal the complex thermal runaway behavior mechanism of overcharged lithium-ion batteries induced and by nail penetration, In this paper, a coupled stimulated thermal runaway experimental platform was built, and experimental studies of overcharge-penetration coupled stimulated thermal runaway and flame eruption dynamics were carried out on 18650-type NCM523 lithium-ion batteries from macro and minutiae viewpoints, in which the states of charge (SOC) of the overcharged batteries were 100 %, 105 %, 110 %, 115 %, 120 %, 125 %, 130 %, 135 %, 140 %, 145 % and 150 %. The results showed that the maximum battery surface temperature during overcharging increased from 32.7°C at 100 % SOC to 66.1°C at 150 % SOC, an improvement of 102 %. The thermal runaway battery temperature increased from 529.0°C at 100 % SOC to 657.1°C at 150 % SOC, an increase of 24.2 %. The thermal runaway maximum flame temperature increases from 485.5°C at 100 % SOC to 983.9°C at 150 % SOC, an improvement of 102.6 %. The flame area of medium overcharged> high-level overcharged> low-level overcharged batteries and the flame area of thermal runaway increased by 22213.95 cm2 compared to the maximum of 100 % SOC, and the flame propagation speed of the batteries after thermal runaway showed that the greater the SOC, the stronger the intensity of the flame. The higher the degree of overcharging, the higher the danger of thermal runaway on the side of the battery and near the positive electrode, and the danger of thermal runaway in overcharged lithium-ion batteries increases with the increase of SOC.

中文翻译：

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过充-渗透耦合刺激诱导NCM523锂离子电池热失控和火焰喷发特性的实验研究


锂离子电池在极端耦合滥用条件下的热失控严重阻碍了锂离子新能源汽车的可持续发展。为揭示过充锂离子电池诱导和针刺的复杂热失控行为机制，本文搭建了耦合受激热失控实验平台，从宏观和细枝两个角度对 18650 型 NCM523 锂离子电池进行了过充-渗透耦合受激热失控和火焰喷发动力学的实验研究， 其中，过充电电池的充电状态 （SOC） 为 100 %、105 %、110 %、115 %、120 %、125 %、130 %、135 %、140 %、145 % 和 150 %。结果表明，过充电时电池表面的最高温度从 100 % SOC 时的 32.7°C 增加到 150 % SOC 时的 66.1°C，提高了 102 %。热失控电池温度从 100% SOC 的 529.0°C 上升到 150% SOC 的 657.1°C，提高了 24.2%。热失控火焰最高温度从 100% SOC 的 485.5°C 增加到 150% SOC 时的 983.9°C，提高了 102.6%。中度过充>高电平过充>低电平过充电池的火焰面积和热失控的火焰面积较100 % SOC的最大值增加22213.95 cm2，热失控后电池的火焰传播速度表明，SOC越大，火焰强度越强。过充程度越高，电池侧面和正极附近发生热失控的危险性就越高，过充锂离子电池中发生热失控的危险性随着SOC的增加而增加。