E-mobility Fire Risk: how to educate, evaluate and mitigate

A stark reminder of this growing risk; in December 2024, an e-bike battery explosion destroyed a family home in South-East London. A converted conventional pedal cycle with a battery pack fitted to it, was being charged inside the property at the time. Footage showed how quickly the house became engulfed in flames and occupants escaping through doors and skylight windows. In this case, one member of the household sustained serious injuries from falling from his escape route and another was treated in hospital for smoke inhalation. LFB noted that it was “fortunate that no lives [had] been lost” in the “devastating” fire.

LFB deputy assistant commissioner, Richard Field, added: “We’ve seen around 160 e-bike and e-scooter fires in London this year and this incident highlights the dangers e-bikes and e-scooters can pose.”

Educate

While they provide a speedy option for zipping from A to B, if the batteries in e-bikes and e-scooters become damaged or begin to fail, they can start incredibly ferocious fires within seconds. Government initiatives and guidance help to mitigate risk to an extent. In October 2024, the Government “Buy Safe, Be Safe” initiative was launched with key safety guidelines but there is still a pressing need for increased education for users, surrounding their devices post-sale.

Leading examples of bodies providing this much needed education include LFB’s #ChargeSafe and Surrey Fire and Rescue Service (SFRS)’s #BatteryWise campaigns.

Why are these batteries a fire risk?

Huge energy, small space

The lithium batteries which power e-bikes and e-scooters, store a whopping amount of energy in a very small space. These batteries are vastly more powerful compared with other types of batteries.

‘Out of control’ energy release

If the energy within the battery is released in an uncontrolled way, wittingly or not via modification, then a fire or explosion may result. The ferocity of flames, which develop so rapidly, quickly escalate situations in residential properties to the incredibly serious and life-threatening.

Thermal runaway

Put simply, thermal runaway is an uncontrollable, self-heating state which occurs when battery temperatures increase too drastically, releasing large amounts of toxic and flammable gases. These gases burst the battery and almost always ignite. Fire then rapidly spreads across all the cells in the battery, causing thermal runaway in otherwise undamaged cells. The explosive nature of the molten metal and the degree of collateral fires it causes is huge, with peripheral fires spreading to surrounding areas rapidly. The Fire Protection Agency (FPA) have described an e-bike or e-scooter battery which goes into thermal runaway “akin to a box of fireworks going off in your bedroom. FPA note calculations which suggest a typical e-bike or e-scooter battery stores the same amount of energy as six hand grenades.

Damaged goods

Batteries can be damaged by dropping them or crashing e-bikes or e-scooters. Where the battery is damaged, it can overheat. Overheating, crushing, penetrating or overcharging can cause a fault in damaged battery cells, leading the battery to catch fire or explode.

User behaviour

Obstruction

Often, devices are stored and charged in communal areas in homes, sometimes overnight in hallways, thus blocking what may be the only escape route in a property. Tragically, a number of fatal battery fires have been attributed to obstructed exits and the rapid, explosive nature of these fires.

Modification

The LFB note that many of these fires are caused by incompatible chargers, modifications to e-bikes, or faulty or counterfeit products, including chargers, lithium batteries and conversion kits. In January 2024, the UK Office for Product Safety and Standards (OPSS) issued a warning about a brand of e-bike battery made in China that was linked to fires. The batteries were sold on online marketplaces like Amazon, eBay, and Alibaba. The report cited that the product presents a serious risk of fire as there is the potential for it to enter into thermal runaway.

LFB deputy commissioner, Charlie Pugsley, notes that “many of the fires we’ve attended have involved secondhand vehicles or bikes that have been modified using parts bought online.” Converting pedal bikes into e-bikes using DIY kits bought online can be very dangerous, posing a higher risk of fire.

Continued efforts

There is a need for on-going, active education and a change in user behaviour in order to effectively mitigate fire risks linked to these types of batteries.

You can find out more about proactive approaches to e-mobility fire safety education, by registering for our upcoming webinar: E-mobility and Fire Safety – Are Facing a Growing Risk?

Visible policies, robustly monitored

General policies restricting the storage of e-cycles, e-scooters and similar items in common areas, stairwells and other fire escape routes should be fully implemented and monitored. These should be visible and allow individuals to take ownership of their safety and surroundings.

Inside individual homes

While the legislation and guidance on storage in communal areas is clear, behind people’s own front doors, an informed level of vigilance is crucial. Inside individual flats, apartments and houses, safe storage of e-mobility devices is still inconsistent at best and alarming at worst.

Outreach to inform, support and monitor safe storage among individual residents inside their own home, has the power to save lives.

An excellent example of this type of outreach, is the vital e-vehicle health check service being offered by housing association, Gentoo, in Sunderland.

The health checks are carried out inside customers’ homes, where vehicles’ overall condition and electrical components are checked and customers are given advice and information from Tyne and Wear Fire and Rescue Service (TWFRS) personnel about how to safely use, store and charge their vehicle.

Join Gentoo’s Gemma Darville and Stacey Thwaites in our upcoming webinar, as they share insights from their proactive approach to e-mobility fire safety. Also joining our guest panel will be Jan Taranczuk, Vice-chair of the National Social Housing Fire Strategy Group (London and Southeast), and Kabbe Njie, Senior Fire Engineer, Heathrow, offering a wider industry perspective on the impact of Gentoo’s initiative.

You can also read more about Gentoo’s effective partnership and how it serves to protect individuals in the community.

Leading safety campaigns

LFB has collaborated with both Amazon and Deliveroo as part of its #ChargeSafe campaign which aims to share crucial, life-saving safety advice to users.

With these commercial giants recognising their role in active education, it is hoped that the growing fire risks associated with e-bikes and e-scooters is addressed.

Amazon

Amazon’s contribution focuses around buying and selling legislation, in response to the potential dangers of ‘at home’ device modification and conversion.

The International Fire and Safety Journal (IFSJ) say that Amazon is enforcing stricter safety standards by requiring sellers to provide proof of compliance with applicable laws and documented testing from accredited laboratories.

Thanks to a collaboration with the London Fire Brigade, when someone buys an e-bike, e-scooter or accessory such as a battery pack, conversion kit or charger from Amazon, they will receive an email notification with easy-to-understand tips on how to use and store them safely.

Deliveroo

In 2024, City of London Police recorded 295 seizures of modified e-bikes. Most of the riders who had illegally modified e-bikes were food deliverers trying to get a faster vehicle to do their job. City of London Police’s Sgt, Stuart Ford, explained, “So they’ll buy a normal bike, and then they’ll buy a kit online of batteries – which are unstable in a lot of cases – throttles and rear hub motors that will turn them into mopeds basically.”

A Deliveroo spokesperson said the company takes its “responsibilities seriously to ensure the safety of riders and the communities where we operate”. In response to the far advanced risk which modified e-battery kits pose, Deliveroo have been active participants in the LFB’s #ChargeSafe campaign, organising ‘Rider Roadshow’ events where delivery riders meet firefighters at stations across London.

The direct engagement for riders emphasises responsible use of e-bikes at home and work and advocates the importance of high safety standards for equipment sold to riders.

Government guidance & law

It is hoped that the Government’s Product Regulatory and Metrology Bill, announced during the King’s Speech in July 2024, will respond to new product risks and “enable the UK to keep pace with technological advances … such as the fire risk associated with e-bikes and lithium-ion batteries.” The Bill, which covers both e-bikes and e-scooters, was introduced in the House of Lords on 4th September, with the Second Reading and Committee Stage starting on 8th October and 4th November 2024, respectively.

It also seeks to ensure that the law can be updated to recognise new or updated EU product regulations (including CE markings), enable improvements to compliance and enforcement and update the legal metrology framework by identifying new and emerging business models in this rapidly expanding market.

The King’s Speech briefing notes detail that “there is an urgent need to legislate to respond to emerging threats to consumer safety, for example, to address issues such as incidents from ingesting button batteries, and e-bike fires where there was a 78 per cent increase in e-bike fires in 2023 compared to 2022 in London according to the London Fire Brigade”.

Evaluate and Mitigate

All e-bikes and e-scooters are different. Evaluate your device and the devices around you, especially in densely populated communal areas. What is the risk? What is the response?

(LFB Guidance, National Fire Chiefs Council (NFCC) NFCC Guidance)

High risk:

Evaluate the device. For any of the indicators below, take immediate action to stay safe and reduce fire risk. Get out, stay out and call 999.

Heat: If your device’s battery feels extremely hot to the touch, it may be defective and start a fire.
Bulging: A battery bulging or swelling out of shape is a common sign of it failing. If your battery looks swollen, you should stop using it immediately. Similar signs include any type of lump or leaking from the device.
Noise: Failing lithium batteries have been reported to make hissing or cracking sounds.
Smell: A strong or unusual smell coming from the battery could be a sign of it failing. 
Performance: A failure to fully charge or longer charge times can be a sign that your battery is failing.
Smoke: If your battery or device is smoking, a fire has already started.
Modification and reputable products: Always use the manufacturer approved charger. If you spot any signs of wear and tear or damage, buy an official replacement charger for your product from a reputable seller.

Medium risk:

Upon evaluation your device appears safe. Now reduce the risk of fire when you charge and store an e-bike or e-scooter.

Avoid storing or charging e-bikes and e-scooters on escape routes or in communal areas of a multi occupied building, which obstructs safe escape routes.
Responsible Persons should consider and offer advice to residents on the risks posed by e-bikes and e-scooters left in common areas, such as means of escape, bike stores and mobility scooter charging rooms. NFCC Guidance
Reduce the risk of overheating by allowing batteries to cool down before attempting to re-charge.
Charge on hard flat surfaces where heat can dissipate.
Do not cover chargers or battery packs when charging, which could lead to overheating or fire.
Do not charge batteries or store e-bikes or e-scooters near combustible or flammable materials.
To reduce damage, ensure batteries are not getting knocked around while in use or being carried. Do not continue to use a damaged battery.
Batteries should never be exposed to extremes of temperature.

Low risk:

Your device is serviced and safely charged and stored. You can continue to enjoy it safely and legally. It is, of course, important that the potential of e-mobility devices is not unnecessarily limited, providing that safe use is prioritised. The Cycle Association (TCA) shared new research in August 2024, revealing that concerns over battery fires are deterring a significant portion of the population from choosing to travel by e-cycle, blocking significant health, environmental and money-saving benefits.

TCA reports that a new survey of UK bike shop staff has found that concerns over battery safety and fire risk is significantly affecting cycling businesses on local high streets throughout the country.

95% of staff have heard concerns from prospective customers about battery fires
25% stated that they believe this has harmed their business.

Meanwhile, The Cycle Association reports that almost two-thirds (64%) of UK adults claim that e–bike education would lower their concerns about purchasing and using an electric bike.

This magnifies the crucial need and opportunity to support both British retailers and potential buyers through education so that they may benefit from and utilise e-mobility safely.

Government guidance from February 2024 on managing fire risk for premises, also highlights the strong need to facilitate responsible use of e-bikes and e-scooters, once the immediate physical provisions for safe charging and storage have been made.

Find out more

Find out more in order to Educate, Evaluate and Mitigate the fire risk posed by these types of batteries. Listen to our previous webinar: E-mobility and Fire Safety – Are We Facing a Growing Risk?

Webinar video and summary