Lithium-Ion Battery Fires: Understanding the Risks and How to Stay Safe

Why are these fires so dangerous?

Lithium-ion battery fires behave differently from ordinary fires. They can:

• Develop very quickly

• Produce intense heat

• Vent toxic and flammable gases

• Reignite after the fire appears under control

• Spread rapidly inside homes, communal areas and workplaces

That is why these fires are such a concern in flats, HMOs, care environments, workplaces and buildings with shared escape routes. London Fire Brigade warns that charging e-bikes or e-scooters in communal areas or escape routes can quickly block people’s way out in an emergency.

Practical lithium-ion battery safety advice

The good news is that many lithium-ion fires are preventable. Safer buying, charging, storage and disposal can significantly reduce the risk.

1. Buy carefully

Choose products tested by a recognised certification body, such as UL or Intertek/ETL, and avoid cheap, unbranded or suspiciously low-cost batteries and chargers. National fire safety campaigns increasingly stress that listed and certified products are far safer than uncertified alternatives.

2. Always use the correct charger

Only use the charger supplied by the manufacturer, or a replacement specifically approved for the device. Avoid generic multi-fit chargers unless the manufacturer has approved them. London Fire Brigade warns that using the wrong charger can put too much power into the battery and greatly increase the risk of fire.

3. Charge on a hard, non-combustible surface

Do not charge batteries on beds, sofas, carpets or under pillows. A hard surface with good airflow is much safer. Guidance from fire safety bodies also advises against leaving charging devices unattended or charging overnight.

4. Keep batteries away from exits and escape routes

Do not charge or store e-bikes, e-scooters or spare batteries in hallways, stairwells or communal areas. If a battery fails, the fire can grow quickly and cut off escape. This is especially important in flats, HMOs and multi-occupied buildings.

5. Watch for warning signs

Stop using the battery immediately if you notice:

• Swelling or bulging

• Excessive heat

• Hissing or cracking sounds

• A strong or unusual smell

• Leaking

• Smoke

• Sudden changes in charging time or performance

These are recognised warning signs of battery failure. If a battery is smoking or on fire, get out, raise the alarm and call 999.

6. Avoid modifications and conversion kits unless properly certified

Conversion kits are a major area of concern. If batteries, motors, chargers and control systems are not designed and tested to work together, the fire risk increases significantly. That is one reason fire services and regulators are focusing more closely on conversion kits and aftermarket components.

7. Store batteries correctly

Where possible, store lithium-ion batteries at room temperature and away from combustible materials. Do not leave them in hot cars, direct sunlight or freezing conditions. Fire safety guidance also advises keeping spare batteries away from anything that can burn.

8. Dispose of batteries properly

Never put lithium-ion batteries in household rubbish or mixed recycling. They should be taken to an appropriate battery recycling point. Incorrect disposal is a known cause of fires in bin lorries and waste facilities.

What should businesses and responsible persons in England do?

For businesses, landlords, managing agents and anyone responsible for premises in England, lithium-ion batteries should now be treated as a specific fire risk, not an afterthought. That means reviewing fire risk assessments, identifying where batteries are charged or stored, and putting sensible controls in place. British Safety Council reporting in 2024 found that 71% of surveyed organisations had not updated their fire risk assessments to cover lithium-ion battery fire risks.

Practical steps include:

• Reviewing where lithium-ion devices are used, stored and charged

• Preventing charging in escape routes and communal areas

• Creating designated charging areas where appropriate

• Training staff to recognise warning signs and respond correctly

• Checking that fire alarms, extinguishers and emergency lighting are suitable and maintained

• Ensuring waste batteries are handled and disposed of safely

• Updating policies for e-bikes, e-scooters and charging on site

What about fire extinguishers?

Not every extinguisher is suitable for lithium-ion battery incidents. For smaller battery fires, a specialist extinguisher designed for lithium-ion risks, such as an AVD-based unit, may help control or cool the fire. However, larger batteries, e-bike battery packs and electric vehicle fires are far more complex and should be treated as a serious emergency. They can reignite, escalate rapidly and require fire and rescue service attendance.

If there is any doubt, the safest response is evacuation, raising the alarm and calling 999.

A growing issue that cannot be ignored

This is no longer a niche fire safety topic. Fire services, regulators and standards bodies are all paying closer attention because the number of incidents is rising and the consequences can be severe. Fire chiefs in the UK have called for stronger product safety rules, tighter control of online sales and improved public awareness. Internationally, safety standards are also moving in the same direction, with more emphasis on certified products, better risk assessment and specialist control measures.

Lithium-ion batteries are here to stay, but the fire risks that come with them need to be taken seriously. Whether at home, in rented property, in the workplace or across a larger property portfolio, safer buying, charging, storage and disposal can make a real difference.

At Fire Guard Services, we help businesses and responsible persons across England identify fire risks, improve compliance and put practical protection measures in place. From fire risk assessments and extinguisher provision to fire alarm maintenance, emergency lighting and staff training, we provide straightforward fire safety support built around real-world risks.