What Happens When a Lithium Battery is Thrown into Fire: Exploding or Not?

In recent years, the use of lithium batteries has become increasingly common, from smartphones to electric vehicles. These batteries store a significant amount of energy and are crucial for modern technology. However, it's essential to understand the potential risks associated with lithium batteries, particularly when they come into contact with fire. This article will explore what happens when a lithium battery is thrown into fire and explain why it might not explode as quickly as you might think.

Understanding Lithium Battery Temperature

Contrary to popular belief, a lithium battery does not 'explode' instantly when it is exposed to fire. Instead, the process is more complex and typically takes a few minutes. When a lithium battery is subjected to high temperatures, several critical events occur:

The Role of the Battery's Coating

The battery's performance and safety are significantly influenced by the outer coating. This coating is designed to protect the battery from external damage and internal failures. When a lithium battery is thrown into fire, the coating can start to melt at a specific temperature threshold, which is typically around 100°F to 150°F (38°C to 66°C) for many types of batteries. Once the coating melts, the battery begins to release gases and may start to catch fire.

The Internal Chemical Reaction

When a lithium battery is exposed to high temperatures, an accelerated internal chemical reaction might occur. This reaction can cause the pressure inside the battery to build up. If the internal pressure becomes too high, the battery may vent, releasing gases and heat. This venting process is crucial in preventing the battery from reaching a point where it could explode.

Temperature Thresholds and Safety

The exact temperature at which a lithium battery will start to catch fire and potentially explode depends largely on the specific type of battery and its internal chemistry. For example, lithium-ion batteries, commonly found in smartphones and laptops, have different safety mechanisms compared to lithium-polymer batteries, which are used in smaller devices like earbuds.

Why Lithium Batteries Don't Explode Immediately

The internal safety mechanisms in lithium batteries are designed to prevent immediate explosions. These mechanisms include pressure relief valves and thermal runaways. When the battery starts to heat up, the valve can release gases, reducing the internal pressure. This valve can significantly delay the process of explosion, preventing the battery from reaching a critical condition.

The Importance of Cooling

Cooling down the battery is one of the best ways to prevent it from exploding. Once a lithium battery starts to catch fire, it's crucial to remove it from the heat source as quickly as possible. Cooling the battery with water or by submerging it can help to reduce the temperature, thereby reducing the risk of an explosion.

Conclusion

While the idea of a lithium battery catching fire and exploding in a fire sounds alarming, it is important to understand that it does not happen immediately. When a lithium battery is thrown into fire, it takes a few minutes for the coating to melt and the internal chemistry to start reacting. This process allows for intervention and cooling measures, reducing the risk of an explosion. Understanding these facts can help ensure safer handling and use of lithium batteries, especially in situations where they might come into contact with fire.