Spate of e-bike and e-scooter fires prompts battery warning

A rise in sales of e-bikes and e-scooters has seen a surge in fires sparked by exploding batteries, with cheaper models often to blame.

They’re fun, convenient, cheap and growing in popularity, but there is also a dangerous side to e-scooters and e-bikes that has authorities concerned.

Market consulting firm P&S Intelligence reports the Australian micro mobility market — which encompasses both electric and traditional bikes and scooters, as well as electric mopeds and three-wheeled ‘pods’ — generated $16.9m in revenue in 2020.

The largest share of that figure was in e-scooter sales, due to their cost effectiveness.

But since then people have been hurt or killed when the rideable devices, mostly powered by lithium-ion batteries, have burst into flames.

Most incidents have occurred with low-quality light electric vehicles while they were charging.

An e-bike battery fire gutted this home in Eastgardens, Sydney on March 19.

EV FireSafe, a body tracking electric vehicle battery fires thanks to Defence Department funding, found 97 people were injured, and eight killed, in 57 separate incidents worldwide since the start of the year.

The project’s director Emma Sutcliffe said 13 of those serious incidents occurred in Australia, with the same number of people being injured.

Among those incidents was a fire that gutted the garage and ground floor of a house at Eastgardens, in Sydney’s east, on March 19.

NSW Fire and Rescue said investigators believed a faulty lithium-ion battery on the bike exploded, causing the fire, which has badly damaged the home and destroyed a car in the garage .

A woman was forced to leap from a second-storey balcony to escape the flames, but no one was harmed.

The battery units on electric rideables can experience ’thermal runaway’ when a damaged lithium-ion cell overheats, heating its neighbouring cells, causing them to rupture, explode, and ignite. Picture NCA NewsWire / Ian Currie

Ms Sutcliffe said there were three issues with low-quality electric vehicles: they often have poor quality lithium ion battery cells and battery management systems; they take a beating in normal operation; and they’re often stored or charged inside a home or workplace, so there is a higher risk of a fire spreading.

“Not all LEVs are poor quality and many companies are using high quality lithium-ion battery cells and battery management systems,” she said.

Battery packs are made up of a module of smaller battery cells, like a group of traditional AA batteries all working together. If damaged or overcharged, those cells can begin generating heat and internal gas build-up.

The heat from the faulty cell spreads to other nearby cells, creating a chain reaction and eventual explosive exothermic reaction as those built up gases burst, catch fire, and vent from the battery module.

“LEV owners should check out their state fire agency advice for lithium ion battery operation, charging and storage,” said Ms Sutcliffe.

“They should also be aware of the early signs of thermal runaway: loud popping noises; hissing or whistling noises; clouds of ‘smoke’ coming from the battery pack — this is actually toxic and flammable gases that can cause respiratory distress, ignite, or explode.”

Damage caused to an e-bike when its battery exploded in Chatswood, Sydney, on February 17.

A council worker put the blaze out with a fire extinguisher, before firefighters arrived and submerged the battery in water.

NSW Fire and Rescue has urged users to take care with selecting their devices and the care and storage of them.

“Faulty or overcharged lithium-ion batteries pose a serious safety risk,” NSW Fire and Rescue says.

“Always stick to reputable and compatible lithium-ion battery brands, avoid over-charging and charging devices whilst you're asleep or away from home.”

Even high quality lithium-ion batteries are capable of creating a fire risk when they experience what’s known as “thermal runaway.”

This was the case for a Queensland mother and her two teenage sons, woken in the middle of the night to popping explosions “like fireworks” when an e-bike caught fire while charging in their Sippy Downs home on February 20.

One of the boys had purchased the e-bike from someone on Facebook Marketplace; it had been left in the house to charge overnight when the battery exploded, gutting the rental property, and leaving the family homeless.

Mother Frances Higgins subsequently warned others from charging their LEV’s inside homes.

Market consulting firm P&S Intelligence found the Australian micro mobility market generated $16.9m in revenue in 2020. Picture: Dan Peled

Meanwhile, the nation’s consumer watchdog is conducting its own investigation into lithium-ion battery fires, with part of the probe focusing on rideables.

The Australian Competition and Consumer Commission (ACCC) released an issues paper on the batteries for consultation last December.

A report on the matter is expected to be released by the end of the year.