Lithium Battery Fires – Risks, Thermal Runaway and Fire Safety Advice

Why Lithium Battery Fires Are Dangerous

Lithium battery fires can be extremely dangerous because they can burn intensely, reignite without warning and release toxic gases.

Unlike many ordinary fires, lithium battery incidents may involve a process called thermal runaway. This happens when heat builds rapidly inside the battery, causing cells to fail in sequence. Once this process starts, the fire can escalate very quickly.

Where Lithium Batteries Are Found

Lithium batteries are now used in many everyday items, including:

• Mobile phones
• Laptops and tablets
• Electric scooters
• Electric bikes
• Electric vehicles
• Home battery storage systems

As these products age, become damaged or are charged incorrectly, the risk of battery failure may increase.

Common Causes of Lithium Battery Fire Risk

Many lithium battery incidents are linked to poor charging practices, damaged batteries or unsuitable chargers. Cheap or incompatible chargers can increase the risk of overheating, particularly with e-scooters, e-bikes, laptops and mobile devices.

Charging devices overnight or in escape routes, such as hallways and stairwells, can be especially dangerous. If a battery fails while people are asleep, or if a fire blocks the exit route, the consequences can be severe.

Off-Gassing and Early Warning Signs

Before a lithium battery bursts into flames, it may begin off-gassing. This means gases are released from the battery as it fails. These gases may be toxic and flammable.

Warning signs may include:

• Hissing, popping or crackling sounds
• Swelling or bulging of the battery or device
• A strange chemical smell
• Smoke or vapour
• Unusual heat from the device

Fire Safety Controls for Lithium Batteries

Lithium battery safety is not solved by one single product. A safe approach should consider:

• Early detection through smoke, heat or gas detection systems.
• Safe charging practices, using the correct charger and following the manufacturer’s instructions.
• Fire containment to help prevent the fire spreading.
• Clear escape routes so people can leave safely.
• Emergency planning so everyone knows what to do if a battery fails.

Charging Lithium Batteries Safely

To reduce the risk of lithium battery fires, always use the correct charger supplied or recommended by the manufacturer. Avoid charging batteries overnight where possible, and never charge e-scooters, e-bikes or large battery packs in hallways, stairwells or escape routes.

Large batteries, including those used for electric vehicles and home energy storage systems, should be installed, charged and maintained according to the manufacturer’s guidance and by competent people where required.

What to Do if a Battery Starts Smoking or Off-Gassing

If a lithium battery starts smoking, hissing, swelling or giving off fumes, do not pick it up. The device may burst into flames without warning.

Leave the area immediately, close doors behind you if safe to do so, call the fire and rescue service and stay out.

Key Safety Message

Get out, call the fire brigade and stay out. Lithium battery fires can escalate rapidly and release toxic gases. Personal safety must always come first.