Teddington residents are being warned not to let their Black Friday bargain go up in smoke in a stark, joint warning over the risks of buying e-bikes, scooters and conversion kits online. 

Consumer safety charity, Electrical Safety First, and the London Fire Brigade have warned that the wrong purchase can lead to serious unintended consequences down the line as the capital's residents look to bag a bargain this Black Friday or Cyber Monday. 

The warning comes as new research, jointly commissioned by Electrical Safety First and the London Fire Brigade, of more than 2,000 Londoners, found that e-bikes and e-scooters both appeared in the top 10 most sought-after products the capital's residents are considering buying this Black Friday. 

Meanwhile, more than 1 in 10 (11%) of those surveyed also said an e-bike conversion kit was a purchase they were most considering this Black Friday.

Separately, 1 in 5 of those surveyed said they would definitely consider taking advantage of a Black Friday/Cyber Monday deal to purchase either an e-bike, e-scooter or e-bike conversion kit.  

Worryingly, of those, more than half (58%) said they would most likely shop for these devices via online marketplaces - sparking fears the capital's Black Friday bargain hunters could unintentionally bag a dodgy deal. 

"Buying from a reputable manufacturer or retailer has never been so vital when it comes to electrically powered bikes and conversion kits." 

Lesley Rudd, chief executive of Electrical Safety First said: "These devices are useful purchases when they are compliant and safe and purchased from a reputable manufacturer, but if they are either substandard, charged incorrectly or conversion kits are installed poorly, they present a risk of a ferocious fire in the event of a catastrophic battery failure.

"With Londoners looking to bag an e-bike bargain this Black Friday, remember that safety starts with where you shop.

"Unknowingly buying a substandard e-bike, charger or conversion kit online could have serious consequences."

Fires caused by batteries in electrically powered bikes and scooters are one of London's fastest growing fire trends with the London Fire Brigade being called out to an e-bike or e-scooter fire on average every other day in the past year. 

London Fire Brigade's Deputy Assistant Commissioner for Prevention & Protection, Richard Field said: "We understand that people are trying to save money, but if you spot a deal this week that looks too good to be true, it probably is. 

"When shopping from third-party sellers via online marketplaces or auction sites, there is not the same level of regulation of products for e-bikes and e-scooters compared to buying from high street shops, so you can't be confident that your purchases will meet the correct safety standards. 

"We are urging anyone looking to buy an e-bike or e-scooter, or the batteries, chargers or conversion kits, to do so from a reputable seller."

Experts are particularly concerned with modified electric bikes and conversion kits that can catch fire if installed to a poor standard, using sub-standard parts or charged incorrectly.  

Electrical Safety First and the London Fire Brigade are also warning shoppers seeking out conversion kits that it is essential a battery is charged with a compatible charger, meaning it supplies the battery with a safe voltage and current.

Conversion kits purchased online often come with a motor, controls and wiring but it is common for them to lack a battery and a charger, so the shopper will often need to purchase these items separately, leaving them at risk of purchasing an incompatible pair.

If an incompatible or sub-standard charger is used, the battery risks overcharging and this increases the risk of the battery catching fire. 

Of the 2,001 Londoners surveyed, more than a quarter (27%) said they would not be confident picking out a compatible charger for an e-bike or e-scooter battery in the event they had to purchase one separately.  

Video footage from Electrical Safety First shows how devastating the consequences can be if a substandard battery is charged with an incompatible charger.

One south west London resident was left in sheltered accommodation after a family member's converted bike caught fire and destroyed their home.

Bus driver, Don Hettiarachchi, 49, who lives in New Malden, has only just moved back into the top half of his home after a devastating blaze back in September this year.

Don Hettiarachchi's house caught fire after his son's e-bike caught ablaze (Credit: London Fire Brigade)

His son's e-bike had been charging for five hours in the conservatory at the back of the house when it burst into flames.

Hettiarachchi said: "I work night shifts and when I heard the smoke alarm, I initially thought it was some car alarms in the street outside. 

"Disorientated, I went to have a look and found the whole of the bottom floor of my home filled with smoke.

'The whole of the bottom floor of my home filled with smoke,' says Don Hettiarachchi (Credit: London Fire Brigade)

"My son's converted e-bike was charging inside the conservatory, had caught fire and the kitchen was full of thick black smoke. 

"Luckily the smoke alarms alerted us to get out of the house. I woke my wife and son, and we escaped outside."

 He continued: "The e-bike was bought second hand by my son, and he'd been using it for about two months.

"It had been charging for over five hours and was on charge at the time of the fire. It was always charged in the conservatory. 

"My wife is still suffering from shock at the moment," he said.

"We both went to the doctor and took a month off work due to the stress.

"We stayed in emergency accommodation that the Council provided because our home was inhabitable. 

"My house insurance expired in the summer. My father-in-law was ill and due to being preoccupied with his illness, I missed paying the house insurance renewal - we lost everything in the fire. 

"For anyone thinking of buying a bargain this Black Friday, my advice is to really do your homework before you buy.

"Make sure the e-bike battery and the charger are compatible with one another. Make sure you buy from a reputable seller that you know and trust. 

"Never leave them on charge unattended, in particular overnight, as you need to react should anything go wrong.

"Don't think it won't happen to you because it happened to us and my whole house was destroyed in less than ten minutes by an exploding battery." 

The Brigade has been running its #ChargeSafe campaign to raise awareness of the fire risks associated with these types of vehicles and seek changes to regulation to prevent poor quality batteries, chargers and conversion kits being sold via online marketplaces. 

Fortunately,Hettiarachchi stored the e-bike in a conservatory as blocking an escape route can be extremely dangerous.

You should always keep an e-bike or e-scooter outside or in a shed.

If this is not possible, you should put it in a room where you can shut a door and contain a fire.

Although the smoke alarm sounded, this incident also highlights the risks of charging whilst people are sleeping as there is less time to react before the fire intensifies.