Sadiq Khan has issued a fire alert about privately-owned e-scooters and online conversion kits for e-bikes.
The Mayor said he had “serious safety concerns” that some lithium-ion batteries bought on the web breached trading standards and were a fire hazard.
The London Fire Brigade revealed that there had been 130 fires this year involving the batteries — 65 used by e-bikes, 24 used by e-scooters and the remainder involving those used in e-cigarettes.
Mr Khan has been warned that lives could be lost and was urged to launch a campaign warning of the dangers posed by the batteries. Some are known to overheat when being charged.
In June, a faulty battery caused a blaze to break out on the 12th floor of a tower block in Shepherd’s Bush that needed 60 firefighters to bring under control.
In July, five people were hospitalised after a house fire in Walthamstow. Firefighters said the cause was the failure of lithium-ion batteries for a converted e-bike.
The following month, four people were taken to hospital after a fire in a flat in Bow. Two jumped from a first floor window after an e-bike being charged in a hallway burst into flames.
Also in August, trains into London Bridge station had to be halted when a blaze in a railway arch being used to store a dozen battery-powered pedicabs went up in smoke.
Mr Khan said: “It’s important that Londoners understand which vehicles are safe and which might not be.
“As e-bikes and e-scooters have become more common, the London Fire Brigade has seen an increase in the number of incidents that they are attending involving lithium ion batteries from these type of vehicles. Conversion kits which allow people to convert a normal bike to an e-bike are the cause of many of the fires. They have usually been bought from an online marketplaces and may not meet the correct safety standards.”
Conversion kits that turn a bike into an e-bike are available for less than £200. Some bikes are fitted with two batteries in “rogue” conversions to increase their speed.
One east London bike shop told the Standard it refused to repair illegally converted e-bikes after finding one was capable of 68mph.
Many Londoners flout the ban on private e-scooters being used on public roads and pavements.
Retailers will come under renewed pressure from the Met police and City Hall this Christmas to remind shoppers of the law.
Lib-Dem London Assembly member Hina Bokhari, who raised concerns at Mayor’s Question Time last Thursday, said: “We must do all we can to prevent a death that could result from charging an e-bike or e-scooter.
“As we are approaching Christmas we do need to be warning Londoners…. and promoting reputable manufacturers of e-bikes.”