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In recent years, reports of lithium battery fires and even explosions have become quite common. Batteries are primarily composed of negative electrode materials, an electrolyte, and positive electrode materials. The graphite used as the negative electrode material, at high temperatures, approaches the properties of metallic lithium; during the decomposition of the SEI layer, the lithium ions embedded in graphite react with the electrolyte and the binder polyvinylidene fluoride, releasing a large amount of heat. Alkyl carbonate organic solutions are commonly used as electrolytes and are flammable. The cathode material is usually a transition metal oxide, which has strong oxidizing properties in the charged state. It tends to decompose at high temperatures to release oxygen; this released oxygen undergoes an oxidation reaction with the electrolyte, resulting in the release of large amounts of heat. The operating temperature of lithium batteries generally does not exceed 60°C. However, in situations such as overcharging, rapid charging or discharging, or short circuits, the battery temperature can rise significantly. In severe cases, this can lead to chain reactions within the battery, resulting in thermal runaway and even spontaneous combustion or explosion of the battery. Therefore, from a materials perspective, lithium-ion batteries pose significant risks; in particular, under conditions of abuse, safety issues become even more prominent. The fire risk of lithium-ion batteries mainly depends on the heat generated by chemical reactions. The fire risk of lithium-ion batteries ultimately depends on the thermal stability of the battery materials, which in turn is determined by the chemical reactions between their internal components. Currently, instruments such as thermal scanners, thermogravimetric analyzers, and heat flux sensors are primarily used to study the thermal stability of battery-related materials. The Japanese EKO heat flux sensor – HF-10S, distributed by GongCaiWang, is suitable for directly measuring the heat flux within materials. By utilizing thermocouples to measure temperature differences, the heat flux passing through can be accurately measured. It can be used in research on the thermal stability of battery materials. Additionally, incompatibility between batteries and chargers also leads to excessive heat generation when charging EV batteries. Some users, when charging their electric vehicles, do not use the original charger. Instead, they simply buy any charger they can find, or even use chargers designed for other vehicles. As a result, the voltage and current output by these chargers do not match those required by their electric vehicles. Although charging is still possible, the battery can become severely heated due to this mismatch in current. It is important to note that batteries should be charged using a dedicated professional charger; otherwise, not only will the battery be damaged, but a fire may also occur.