Is thermal runaway a serious risk for lithium batteries?

Understanding Thermal Runaway

Thermal runaway occurs when a lithium battery’s internal temperature exceeds its safe operating range, usually above 120°C (248°F). This can be triggered by various factors, including overcharging, physical damage, or manufacturing defects. Battery management systems (BMS) can mitigate this risk by monitoring temperature and voltage, but even with proper BMS, high-stress conditions can still lead to thermal runaway.

Causes and Prevention

One of the main causes of thermal runaway is the buildup of internal pressure due to gas evolution. Lithium-ion batteries can produce gas when there is electrolyte degradation or other internal issues. To prevent this, it’s essential to use high-quality cells with robust internal design, such as those with internal pressure relief valves or advanced separator materials. Additionally, proper battery handling, storage, and charging practices can minimize the risk of thermal runaway.

Mitigation and Safety Measures

To mitigate the risks associated with thermal runaway, lithium battery manufacturers and users must prioritize safety. This includes implementing strict quality control measures, using protective packaging and shielding, and ensuring proper installation and maintenance. In the event of a thermal runaway incident, having a fire suppression system in place can help prevent property damage and minimize the risk of injury.