What Causes Lithium Batteries to Catch Fire?
5 Answers
Lithium batteries catch fire due to separator damage or excessive temperature. There are two common types of lithium batteries: lithium iron phosphate (LiFePO4) batteries and ternary lithium batteries. These two types of batteries have different cathode materials. Lithium iron phosphate batteries have better safety performance and will only combust at temperatures around 800°C. Ternary lithium batteries are less safe compared to lithium iron phosphate batteries and can combust at temperatures as low as 200°C. All lithium batteries contain a separator inside, which allows lithium ions to pass through but blocks electrons. This forces electrons to travel through the external circuit, thereby generating electric current in the external circuit.
Lithium battery fires are primarily attributed to thermal runaway processes, which I frequently encounter when dealing with electric vehicle battery issues. Thermal runaway occurs when heat accumulates too rapidly inside the battery, causing chemical reactions to spiral out of control and release massive energy; it commonly happens due to overcharging, deep discharging, or exposure to high external temperatures, especially after parking in summer. Poor heat dissipation between battery cells can lead to a chain reaction of rising temperatures, ultimately igniting the electrolyte or separator. Additionally, manufacturing defects such as electrode impurities or faulty protection circuits can also trigger it. Preventive measures include using certified chargers, avoiding battery storage in sun-exposed locations, and regularly checking for aging signs like swelling. If you detect a burning smell or abnormal heating, immediately power off and seek professional repair assistance.
My neighbor's electric vehicle caught fire before, and the root cause was physical damage. Lithium batteries are fragile inside; drops, impacts, or punctures by sharp objects can easily damage their structure, leading to internal short circuits and fires. In daily use, factors like prolonged heavy-load driving or frequent fast charging can also increase stress, causing the battery to fail prematurely. Uneven battery quality is another factor; some people buy cheap, low-quality products with inadequate fireproof designs. If you notice strange noises or deformities in the battery, stop using it immediately and keep it away from heat sources. Prevention is crucial—I recommend securing the device properly, avoiding compression, and not placing flammable materials nearby while charging.
As a seasoned driver with years of experience, I believe the key cause of lithium battery fires is misuse or improper operation. Overcharging and over-discharging are the most common issues, as many people forget to unplug after charging, leading to excessive current that triggers uncontrolled chemical reactions. If the battery management system fails and cannot maintain voltage balance, the risks become even greater. During hot seasons when using air conditioning or engaging in aggressive driving, the sudden increase in battery load can easily trigger a fire. Early warning signs include failure to charge or sudden performance degradation; in such cases, avoid forcing usage and instead seek manufacturer inspection. Pay attention to maintenance details, such as regularly cleaning dust from connection points and ensuring a well-ventilated environment for safety.
Looking back at past accident cases, lithium battery fires often stem from inherent defects. For example, in certain batches of electric vehicle batteries, improper assembly at the factory led to short circuits between electrodes, causing spontaneous combustion. Design shortcomings are also an issue; insufficient battery pack protection or isolation failure makes them prone to damage during vibrations. External factors such as humid environments can cause corrosion, leading to internal electrolyte leakage and fires. In terms of user habits, mismatched chargers or prolonged charging sessions are hazardous. To reduce risks, opt for certified products, follow the user manual, and replace aging batteries promptly for peace of mind.
