At the start of February, I had a guest visiting Alexandra to compete in the Mountain Bike Orienteering series. He was using an eBike (fair enough, as he’s a few years older than me) and after a big day of riding, he needed to recharge his battery.

It was a scorching hot day, so while we cooled off outside, he plugged the charger into the battery inside the house. When I later went inside, I noticed a distinct smell of overheating plastic. I immediately switched off the charger. It was hot to the touch, and the battery was warmer than usual—just on the edge of being concerning.

After some investigation, we found the issue: the plug connecting the wall to the charger had become loose, causing a poor connection and likely some minor arcing. We cleaned all the connections, ensured everything was securely plugged in, and moved the charger onto a tiled surface before trying again. This time, the battery charged normally, with only the expected slight warming.

But the situation left me wondering, what if we had gone out for the evening and left it charging unattended?

Tips for Safe Battery Charging

To reduce the risk of battery fires, here are some key precautions to take:

• Charge batteries in a safe, well-ventilated area. Ideally, use a concrete surface and keep them out of direct sunlight. Let the battery cool down before charging.
• Inspect your battery regularly. Watch for damage, such as dents, puffiness, deformities, overheating, strange smells, slow charging, or reduced performance. If you notice any of these, dispose of the battery safely (check the CODC rubbish guide for proper disposal methods).
• Be extra cautious after crashes. eBike and scooter batteries can become compromised after an impact, even if they appear fine externally.
• Use the correct charger. Don’t just use any charger that fits; always match the output voltage and Ah rating to your battery’s requirements.
• Monitor charging batteries. Check on them regularly and have a fire extinguisher nearby. Water won’t help in a battery fire.

What to Do in Case of a Battery Fire

If a fire breaks out, dial 111 immediately.

If it’s safe to do so:

• Use a fire extinguisher to prevent flames from spreading.
• Contain the fire with a fire blanket.
• If possible, move the burning battery to a safe distance away from other flammable materials.

By taking a few simple precautions, you can significantly reduce the risks associated with charging eBike batteries. Stay safe, and always be aware of potential hazards—because a little vigilance can prevent a major disaster.