As our cities become more crowded and public transport is not always a suitable alternative, electric bikes and scooters have become more common on the streets of the UK.

They represent a fast way of getting around the crowded streets, but also come with serious fire risks that many remain unaware of, including owners and users of these increasingly popular forms of transport. As ownership increases, so does the importance of understanding safe storage and charging practices to ensure that those fire risks are understood and minimised.

Powered by Lithium-ion batteries, electric bikes and scooters present similar risks to other vehicles and devices such as laptops and smartphones which use lithium-ion batteries as well. When they go into thermal runaway, Lithium-ion battery fires can spread incredibly quickly and become difficult to control – even for professionals.

In this article, we’re going to talk about some of the specific fire risks associated with electric bikes and scooters, as well as the risks brought about by poor ownership, and what you can do to minimise these risks.

We’ll use specific examples to explain what has already happened here in the UK, as well as expert tips from experienced, knowledgeable members of the Firechief® team that you can implement right away to keep your family, your property and yourself safe.       

What causes electric bike and scooter fires?

Let’s get straight into the facts and figures. According to the UK Government Office for Product Safety and Standards (OPSS), there were 199 fires involving electric bikes or scooters in 2023 – 176 of which were in London.

The risks have now become so significant that the London Fire Brigade has classed electric scooter and bike fires as the capital’s fastest-growing fire trend, with their crews attending one fire every two days.

One of the main reasons for the rising trend is the number of faulty or counterfeit conversion kits now available to buy online, enabling owners to perform upgrades using more affordable equipment that does not meet the specifications of the manufacturer.

A prime example of this was a recent house fire in Coventry which resulted in the tragic death of two people. Firefighters deemed that the fire was started by a converted electric bike (the owner having tried to make their pedal bike into an e-bike), which was stored in the hallway of the property. The fire itself was tackled by firefighters from four engines from the West Midlands Fire Service who took just over an hour to fully extinguish the blaze.

Another key fire risk comes from the use of incompatible chargers. The problem with growing trends in the technology industry is that the market can quickly become saturated with less expensive products, that claim to offer the same or better performance than the original equipment manufacturers (OEM) products.

When an OEM brings a product onto the market, they do so having done months, even years of testing and ensuring that their products meet the required safety standards. Third party manufacturers will often choose to produce ‘competitive’ products using lower quality components and without the testing or certifications required to guarantee safety for the user and those around them. This is something that Electrical Safety First have written about in more detail here as part of a campaign to tackle these “deadly” products.

This also means that people put themselves and their property at risk each and every time they plug e-bike or e-scooter batteries in to charge, which has, unfortunately, resulted in disastrous fires that have the potential to destroy not only the e-bike or e-scooter itself, but their home and possessions, too.

Senior Technical Consultant here at Firechief®, Matt Humby, says “As with any Lithium-ion battery device, the key is to educate yourself on the risks surrounding these fires.

“Whilst in most cases a thermal runaway event will be rare, the best advice is to follow some basic safety tips to make sure you are always buying these products from a reputable source, when and how to charge your device and signs of thermal runaway to look out for.

“Make sure you get into a habit of safe charging - any small change in how you view, treat, use your device could make a huge difference. Lastly, if you spot any signs of battery damage, never put the battery back on charge. Recycle it and purchase a new original one from the producer, or an authorised dealer.”

Are there any signs to look for before a fire starts?

There are several common signs that an e-bike or e-scooter might be at risk of catching fire, and these are consistent with most Lithium-ion battery fire indicators.

• Overheating and smoke. The generation of heat is normal for battery-powered devices, especially when they are plugged in to charge or in use. However, you’re likely to know when a battery is at risk of overheating by the fact that it’s hot to touch or, worse, starting to smoke. If the battery is emitting smoke, the process of catching fire is already starting, and you need to take action. Also, be aware that the smoke coming from a battery is likely to be highly toxic, so you should distance yourself from a smoking battery as soon as possible.
• Noise. As we learn more about Lithium-ion batteries and the devices that use them, we start to recognise a lot of the sounds they make. Failing Lithium-ion batteries tend to make a cracking sound or a hiss before they catch fire so if you notice your device doing the same, it’s time to act.
• Smell. Similarly, a smell coming from the e-bike or e-scooter is a good indication that there may be a problem.
• Decreased performance. Finally, the failure to reach a full charge or taking longer than usual to reach your desired charge level is a sign that the battery is starting to fail. It could also be the case that the e-bike or e-scooter is down on power when in use, perhaps failing to reach the acceleration levels you would expect under peak performance. Again, this could be a sign that the charger or equipment you’re using is defective and at risk of catching fire.

Is it safe to store e-bikes and scooters indoors?

Generally speaking, it is not safe to store an e-bike or scooter indoors because of the fire risks associated with lithium-ion batteries. Lithium-ion batteries burn in a very intense way, with temperatures potentially reaching over 1000°C, large flames and toxic fumes.

Instead, what you should do is store and charge your electric bike or scooter in a garage, shed or outbuilding but away from flammable or combustible materials.

Of course, that is not always possible. So, if you have no alternative but to charge your e-bike or e-scooter indoors, be sure to take fire safety precautions including the installation of a smoke alarm,  regularly checking the condition of the battery and charger and ensuring that you do not block any escape routes just in case of fire.

Should I leave an e-bike or scooter battery on charge overnight?

No, absolutely not. You should never leave devices such as these charging unattended for a long period of time. Charging overnight or when you are not fully alert or able to keep a close eye on it increases the risk of fire.

Current advice and good practice is to charge a battery to around 80% and then take it off charge. This will save you charging costs, extend the life of the battery, and reduce the risk of thermal runaway due to overcharging.

The risks associated with lithium-ion battery fires are so great that users are being advised to charge their electric bikes and scooters during the day, in a safe place and with the right fire detection and prevention methods in place.

Should I remove an electric bike or scooter battery in winter?

If the cold, dark and wet winter months are not your cup of tea and you’re unlikely to use your e-bike or e-scooter for a while then you should remove the battery and store it inside at room temperature.

Leaving a battery outside in cold (or warm) weather can affect the performance of the battery, meaning that when you come to use it again, it will struggle to achieve full charge. The e-bike or e-scooter itself can and should remain in your shed or garage as it is the lithium-ion battery that is likely to be affected by the conditions.

For further guidance on cold weather storage and battery maintenance, check out this useful guide from Giant Cycles, who also recommend charging the battery to around 60 per cent until you’re ready to ride again.

Is there a safety standard for electric bikes and scooters?

The EN 15194 standard covers electric bikes.

In the UK and France, it is mandatory for all bikes to comply with the standard, which regulates the overall safety, performance and design of the electric bikes.

At the time of writing, there is not a specific EN safety standard for e-scooters.

Are there any tips or regulations for electric bike or scooter storage in the workplace?

A lot of people are purchasing electric bikes and scooters as a means of getting to and from work without having to worry about parking charges, purchasing travel cards for public transport networks, paying to travel into cities such as London, or simply sitting in traffic.

This creates another series of challenges, however, as it means employers need to consider storage and charging in their own policies and fire safety regulations. Those willing to accommodate electric bikes and scooters are likely to ask employees to ensure safety and compliance by:

• Charging in designated areas that are safe and compliant to fire safety regulation
• Using approved chargers to minimise the risk of fire in the workplace
• Monitoring charging and avoiding leaving it unattended for extended periods

How to prevent e-bike and e-scooter fires

With the increased use of electric bikes and scooters, the risk of fire also increases as we’ve touched on already.

As the trend in sales is showing no signs of slowing down, and in addition to the guidance we’ve shared already, there are a number of key takeaways for owners to help prevent fires:

Safe charging

• Follow the manufacturer’s instructions
• Always unplug your charger when not in use
• Use the manufacturer-approved charger
• Buy an approved replacement if the original battery shows signs of wear or damage
• Charge while you are awake and alert so you can respond to a fire quickly

Safe storage

• Never store or charge electric bikes or scooters in communal areas or escape routes
• Store electric bikes, scooters and their batteries in cool places, but avoid extremes of heat or cold
• Follow manufacturer instructions for lithium-ion battery storage if they are not going to be used for a significant period

Safe purchasing

• Only purchase from reputable retailers – including batteries
• Check that products conform to any relevant British or European safety standards
• Register products with the manufacturer to validate your warranty

Safe disposal

• Check the condition of your battery regularly, and replace it if there are signs of damage
• Never dispose of your battery in household waste or recycling. Manufacturers may offer a dedicated recycling service, or you can check with your local council.

Disclaimer

The information contained within this blog is provided solely for general informational and educational purposes and is not intended as a substitute for professional advice. Before taking any actions based upon this information, we advise the reader to consult all relevant statutory or regulatory guidance and where felt necessary to consult a qualified fire or industry regulation professional. The use or reliance on any information contained herein is solely at the reader's risk.