Lithium-ion batteries, which power almost everything from your smartphone to an electric bike, have become the fastest growing cause of fires in British homes.
Reports from fire departments and insurance companies indicate that the number of incidents involving these batteries has more than doubled in the past two years. Although the technology is fundamentally safe, a specific combination of factors turns everyday objects into high-risk devices.
Main culprits: Micro-mobility in the first place
The London Fire Brigade (LFB) statistics are unrelenting: electric bicycles and electric scooters are by far the most common cause of fatal battery-related fires.
Interestingly, the biggest risk comes not from factory models of renowned brands, but from DIY conversion kits. Users often buy cheap kits online that do not have adequate battery management systems (BMS).
Although e-bikes are the most dangerous due to the size of the battery, the items that break down most often and cause smaller (but still dangerous) fires are smaller devices:
- Vape devices (Vapes): Due to the low price and often questionable quality control, the batteries in cheap vapes are prone to short circuits.
- Mobile phones and laptops: Although they are safer, the risk increases with the use of non-original (“third-party”) chargers that do not communicate properly with the battery, leading to overheating.
- Cordless vacuum cleaners and power tools: These devices use powerful batteries that are often charged in storage rooms or garages, where a fire can go unnoticed for a long time.
Why does the disaster happen?
Insurance experts highlight three key risk factors.
In the first place are cheap chargers, because using a charger that is not intended for a specific device can damage the battery cells.
Physical damage is also a common problem. Dropping a phone or hitting an e-scooter battery can cause an internal short circuit that may not manifest itself immediately, but hours later during charging.
You should also pay attention to unattended charging, because most fires happen at night. When the battery overcharges or malfunctions, sleeping users have very little time to react due to the toxic fumes.
A special problem with the ignition of lithium batteries is the so-called “Thermal Runaway”., because when a battery like this catches fire, it doesn’t burn like an ordinary fire. It is a chemical reaction that creates its own oxygen, producing an intense flame that is nearly impossible to extinguish with standard apparatus.
How to reduce the risk?
British authorities and insurers recommend the “golden rules” of digital hygiene:
- Using original chargers: Savings on a charger of 10 euros can cost an entire household.
- Watch out for evacuation routes: Never charge an e-bike or scooter in the hallway or near the front door – if it catches fire, it will block your only exit.
- Smoke detection: Install smoke detectors in rooms where devices are charged, especially if they are garages or utility rooms.
Technology demands respect
Lithium-ion technology is a marvel of modern engineering, but it requires strict discipline. As batteries become more and more energy dense, the tolerance for mistakes (and bad chargers) becomes less and less. In 2026, the energy security of the home is no longer just a matter of fuses and installations, but also awareness of what exactly we put on the charger before turning off the light, writes Homebuilding.