Why Can’t You Put Out a Lithium Battery Fire? Understanding the Risks and Chemistry

As winter approaches, many people are turning to heated vests and clothing to keep warm. These garments often rely on lithium batteries, which are known for their high energy density and long-lasting power. Some advanced heated lithium batteries can even last up to 20 hours, compared to the typical 3 to 10 hours for most heated clothing. However, lithium batteries come with their own set of risks, one of which is the potential for a fire that is difficult to extinguish. In this post, we'll explore why lithium battery fires are so challenging to put out.

The Chemistry Behind Lithium Batteries

Lithium batteries contain a lithium metal or lithium-ion anode, a cathode, and an electrolyte. The electrolyte is usually a lithium salt dissolved in an organic solvent. When the battery is in use, lithium ions move from the anode to the cathode, releasing energy. However, if the battery is damaged, short-circuited, or overheated, this can lead to a thermal runaway reaction.

What is Thermal Runaway?

Thermal runaway is a self-sustaining reaction that occurs when the heat generated by the battery exceeds its ability to dissipate that heat. This can lead to a rapid increase in temperature and pressure within the battery, causing it to catch fire or even explode.

Why is a Lithium Battery Fire Hard to Extinguish?

  1. Self-Oxidizing: Lithium is a highly reactive metal that can self-oxidize, meaning it can sustain a fire even without an external source of oxygen. This makes it difficult to smother the fire with traditional methods.
  2. High Temperatures: The temperatures in a lithium battery fire can reach up to 1000°F (538°C), which is much higher than typical fires. This can cause the fire to spread rapidly.
  3. Chemical Reactions: The electrolyte in lithium batteries can decompose into gases like hydrogen, which are highly flammable and can intensify the fire.
  4. Water Reactivity: Using water to extinguish a lithium battery fire can be dangerous because lithium reacts with water to produce hydrogen gas, which can lead to an explosion.

Safety Measures and Best Practices

  1. Use a Class D Fire Extinguisher: This type of fire extinguisher is designed for metal fires and is the most effective way to put out a lithium battery fire.
  2. Isolate the Area: If a lithium battery catches fire, it's crucial to isolate the area to prevent the fire from spreading.
  3. Professional Help: Always call emergency services when dealing with a lithium battery fire.
  4. Quality Matters: Always opt for high-quality lithium batteries from reputable manufacturers to minimize the risk of a fire.


While lithium batteries offer many advantages, such as long-lasting power for heated clothing, they also come with risks. Understanding why lithium battery fires are hard to extinguish can help you take the necessary precautions to handle them safely. Always follow the manufacturer's guidelines and be prepared for emergencies to ensure a warm and safe winter.

Stay informed, stay safe!