Firefighters have issued a fresh safety warning after an e-bike battery caught fire in Shoreham, adding to growing concerns about the risks linked to lithium-ion batteries — particularly those used in aftermarket conversion kits.
The incident happened on Monday afternoon in Church Green, when a lithium-ion battery fitted as part of an e-bike conversion kit overheated and ignited.
While no one was injured, the fire required specialist handling by fire crews and serves as a reminder that these batteries can fail suddenly and violently.
What happened in Shoreham
Crews from West Sussex Fire & Rescue Service attended the scene and found the battery burning intensely.
As is standard practice with lithium-ion battery fires, firefighters submerged the battery in water to cool it and prevent re-ignition.
A thermal imaging camera was then used to monitor the battery’s temperature, as lithium-ion cells can continue to generate heat long after flames appear to be extinguished.
Growing popularity, growing risk
Crew commander Mike Wattam said the incident reflects a wider trend.
“E-bike conversion kits are becoming increasingly popular,” he said, “but they pose a serious fire risk when incompatible batteries and chargers are used.”
Unlike factory-built e-bikes, conversion kits often involve mixing components from different manufacturers.
If batteries, chargers and control units are not designed to work together, the risk of overheating, short-circuiting or thermal runaway increases significantly.
Why lithium-ion battery fires are so dangerous
Lithium-ion batteries store large amounts of energy in a compact space. When something goes wrong — whether through damage, overcharging, poor-quality components or incorrect installation — that energy can be released extremely quickly.
Fire services across the UK have warned that lithium-ion battery fires:
- Burn hotter than conventional fires
- Can re-ignite hours later
- Produce toxic smoke
- Are difficult to extinguish without specialist techniques
This is why the Shoreham battery had to be cooled in water and monitored closely.
Buy from reputable sources
Mr Wattam also stressed the importance of where equipment is purchased.
“Electronic devices, batteries and chargers should only be bought from reputable retailers to ensure they meet UK product safety standards,” he said.
Cheap or unbranded batteries and chargers sold online may not meet safety requirements and are increasingly being linked to fires in homes, garages and public spaces.
Don’t DIY battery modifications
Station manager Darren Wickings, who also chairs the multi-agency lithium-ion awareness group Liberate, urged cyclists to think carefully before attempting conversions themselves.
“If you’re considering converting a bike, seek professional help,” he said.
“Always follow the manufacturer’s instructions and never modify or tamper with the battery, charger or motor.”
He added that only the correct charger should ever be used and that charging should take place:
- On a flat, stable, non-combustible surface
- In a well-ventilated area
- Never overnight
- Never while unattended
Charging safety matters
Fire services are increasingly concerned about where and how lithium-ion batteries are charged. Mr Wickings also advised people to:
- Charge batteries away from escape routes
- Avoid charging near soft furnishings or combustible materials
- Ensure working smoke alarms are installed nearby
- Choose locations with a clear means of escape in case a battery fails
Many serious fires linked to e-bikes and scooters occur while batteries are charging — often late at night, when occupants are asleep and escape times are reduced.
A wider fire safety lesson
While this incident was resolved quickly, it reflects a growing national issue as e-bikes and conversion kits become more common. Fire services across the UK have reported sharp increases in fires involving lithium-ion batteries used in:
- E-bikes
- E-scooters
- Power tools
- Mobility aids
The message from firefighters is consistent: these products can be used safely, but only when installed correctly, charged properly and bought from trusted sources.
A timely warning
The Shoreham fire ended without injury, but it could easily have been more serious if it had happened indoors or overnight.
As lithium-ion powered devices become part of everyday life, fire services are urging people to treat batteries with the same respect as any other high-energy electrical system — because when they fail, they do so fast, fiercely and with little warning.
