There is an urgent need for research into the quality of bike batteries and the causes of the fires involving them. That is the view of fire prevention expert Tim Renders.

According to Renders, the numbers of reported e-bike fires in Flanders and the Netherlands rose from 38 in 2021 to 102 in 2023 and 104 in 2024. So far this year, the total has already reached 65.

It is striking that e-bikes are catching fire often, even when they are not plugged into a charger.

After a fall, a battery can catch fire weeks or months later

Renders himself also emphasizes that the actual figure is undoubtedly higher, because many incidents do not receive media attention, or because not all of them are recorded in fire safety statistics.

At the same time, he warns in the newspaper Het Laatste Nieuws that it is a dangerous misconception to believe that the fire hazard posed by e-bikes exists only when they are charging.

For example, in July in West Flanders, an e-bike caught fire while its owner was riding it home. In Zomergem, East Flanders, a home sustained severe damage after the battery of an e-bike caught fire, even though it wasn’t charging.

When an e-bike falls, the separator between the positive and negative electrodes in the battery can become damaged, leading to thermal runaway – a buildup of heat that is difficult to stop.

This process can occur at any time, including hours of days, or even weeks or months after the damage occurs, so not necessarily while the bike is charging.

More control on quality and safety of e-bike batteries

That is why experts such as Renders and the Flanders Firefighters Association are calling for an official investigation into the quality and safety of e-bike batteries. Certified brands must comply with European standards and the new EU Battery Regulation. Many fires often involve cheap, non-genuine, or illegally modified batteries – not necessarily the original manufacturer’s battery.

However, the EU Battery Regulation, which has been in effect since February 2024, focuses primarily on the recycling, reuse, and sustainability of bicycle batteries – not on the type of fire prevention tests advocated by Renders and the Dutch Consumer’s Association.

No harmonized standard for e-mountain bikes and e-cargo bikes

Since May of this year, a harmonized European technical standard for e-bikes has been in effect, known as EN 15194. It specifies the following: maximum continuous motor power (250 W), the speed at which assistance cuts off (25 km/h), and requirements and test methods for the motor drive system, the electrical circuits, charging systems up to 48 V DC, and – importantly – the batteries. Manufacturers who comply with this standard are presumed to also meet the legal safety requirements.

The standard makes battery safety a strict, mandatory requirement- e-bike batteries must now be tested in accordance with EN 50604-1+A1, a stricter version specifically designed for light e-vehicles. However, it applies only to “standard” Electrically Power Assisted Cycles (EPACs). There is currently no harmonized standard for e-mountain bikes, e-cargo bikes, and other LEVs, such as e-scooters.

No control by a government agency

Of course, this standard does not apply retroactively; it applies only to bicycles introduced to the market as new after May 15, 2026. The millions of e-bikes and replacement batteries already in circulation – many of which will remain in use for years to come – will continue to operate under the old, less stringent regulations. Since batteries typically last four to six years, it will take a lot of time before the existing fleet is fully replaced.

Furthermore, the standard is based on a “presumption of conformity”: manufacturers themselves declare that they comply with the standard (CE marking), without a government agency systematically verifying this in advance. And while this standard does test for product defects in new batteries, it does not cover damage caused by drops, improper storage (sunlight, freezing temperatures), aging, or improper charging practices.

Experts and consumer advocacy groups therefore point out that while the standard itself represents a real improvement, there is still a huge gap in enforcement, the existing fleet, and the market segment outside of regulated retail – individual replacement batteries, used batteries, and cheap imports via platforms such as AliExpress or Temu often fall outside the scope of market oversight in practice, even though they are formally subject to the same rules.

Few tips

With nearly 300,000 units sold, e-bikes accounted for approximately 51% of total bicycle sales in Belgium last year. Just as in our neighboring countries, the number of e-bikes is growing rapidly, and statistically, more e-bikes also mean more incidents – even if the risk per bike remains the same.

Apart from that, cheap replacement batteries, improper storage (too hot, too cold, in a storage area with flammable materials), and poor maintenance also play a role.

Experts advise never storing an e-bike or battery in an entryway or other escape route. If you do store them indoors, do so only in a room with a smoke detector. Companies such as Mobile Locker and Nauta Security Storage for example, are also developing fire-safe lockers specifically designed to store bike batteries safely.