He said users should charge the devices uncovered and on hard surfaces that would dissipate any buildup of heat.
A battery in thermal runaway could spit flaming material and the fire could easily spread, he said.
“In a home situation the best thing to do is get out of the way of the battery. There’s very little you can do without protective clothing, a very good understanding of the battery chemistry, in order to safely extinguish the fire.”
People should avoid charging the devices in their homes while sleeping or where they might block escape routes, he said.
Jonno Leonard, of Electric Scooter Shop in Auckland’s Takapuna, said he was yet to see a scooter catch fire in more than six years of selling and maintaining them.
The batteries were one of the most robust parts of the scooter but his staff were aware of the potential and prepared if things should go wrong, Leonard said.
“We do have a lithium ion-specific fire extinguisher because you definitely don’t want to be spraying water on a fire like that. We’ve also got leather welding gloves and masks in case we did have to pick something up that had started to smoulder and get it out of the building.”
The growing popularity of e-scooters meant people should be wary of cheap or second-hand scooters, he said.
A major red flag was if the charger was not matched in specification or brand to the scooter.
“I’ve seen some absolutely dreadful products and [they] turn up for servicing at our place quite often. Sometimes you have to turn it away and say ‘look, we don’t actually know what that is’,” Leonard said.
My Ride Bike store owner Fraser MacMaster said his business had sold and worked on thousands of lithium ion-powered e-bikes without incident.
Bikes and scooters should be well maintained and chargers turned off as soon as the battery was full, he said.
“Chargers do get warm and so you should always be able to touch the charger. If you can’t touch it because it’s too hot then something’s going wrong,” MacMaster said.
