Electric Bike Batteries: Can They Explode?

Electric bike batteries have been in the news a lot recently, with a surge in fires and explosions. In the first half of 2023, the London Fire Brigade were called to an e-bike or e-scooter fire once every two days. In New York, six people died in 2022 due to fires started by e-bike batteries. So, what's causing these incidents? And are some batteries more likely to explode than others?

Cheap e-bikes and low-quality batteries are more likely to explode

Electric bike batteries can explode, catch fire, or exhale toxic gases. Cheap e-bikes and low-quality batteries are more likely to explode due to a lower-quality manufacturing process. If battery companies cut corners or use cheap materials, there’s more likely to be a defect that can lead the cells to expand and bulge. If they bulge, they can burst, which can also cause thermal runaway.

In 2022, six people died and 76 were injured in New York due to fires started by e-bike batteries. In the first half of 2023, the London Fire Brigade (LFB) was called to an e-bike or e-scooter fire once every two days. Four UK deaths in the first three months of 2023 were due to exploding lithium-ion batteries in e-bikes and e-scooters.

While high-quality batteries from brands like Bosch, Shimano, Yamaha, and Giant hardly ever catch fire, even reputable companies can make mistakes. For example, one of the best cell companies on the market had to recall 3 million devices because they kept exploding.

The greatest scrutiny is on electric bike conversion kits because they’re unregulated. This lack of regulation means that many kits available online don't include the battery.

Lithium-ion batteries can explode, catch fire, or exhale toxic gases

Electric bike batteries can explode, catch fire, or exhale toxic gases. Lithium-ion batteries, in particular, have been described as "deadly e-bombs in Britain's homes" by the *MailOnline* after four people in the UK died in the first three months of 2023 due to exploding batteries in e-bikes and e-scooters. In New York, six people died in 2022 due to fires started by e-bike batteries, and 76 were injured.

The likelihood of a battery exploding is increased by cheap manufacturing processes, which can lead to defects that cause the cells to expand and bulge. If they bulge, they can burst, which can also cause thermal runaway. According to Leo Raudys, president and CEO of Call2Recycle, a nonprofit battery-recycling program, "You just have to remember, you get what you pay for. These batteries are highly engineered devices, and if you’re only spending a couple of hundred bucks on a battery, you’re probably getting one that’s cutting corners in a number of different places".

However, even batteries from reputable companies can explode. One company had to recall 3 million devices because they kept exploding.

Electric bike conversion kits are also a cause for concern, as they are unregulated and many kits available online do not include the battery.

Electric bike conversion kits are unregulated and a cause for concern

The greatest scrutiny is on electric bike conversion kits because they are unregulated. This lack of regulation means that many kits available online do not include the battery. As a result, buyers may be tempted to purchase low-quality batteries, often imported from China, which are more likely to explode due to a lower-quality manufacturing process. If battery companies cut corners or use cheap materials, there is a higher chance of a defect that can lead the cells to expand and bulge. If they bulge, they can burst, causing thermal runaway and an explosion.

Even reputable companies can make mistakes, so it is important to treat electric bike batteries with respect and care. It is recommended that you visually inspect the battery for damage.

The surge in electric bike battery fires has led to parking restrictions for electric bikes in some condos worldwide.

Fires started by e-bike batteries have caused deaths and injuries

E-bike batteries can catch fire due to internal faults, physical or electrical abuse, or extreme temperatures. If the battery cells overheat, it can cause exothermic reactions and more heat spreads. Eventually, the cell becomes unstable and collapses, leading to flammable and toxic gases, fire, and explosion.

The greatest scrutiny is on electric bike conversion kits because they are unregulated. This lack of regulation means that many kits available online do not include the battery. Experts say that cheap e-bikes and low-quality batteries, often imported from China, are more likely to explode due to a lower-quality manufacturing process. If battery companies cut corners or use cheap materials, there is a higher chance of a defect that can lead the cells to expand and bulge. If they bulge, they can burst, causing thermal runaway.

However, it is important to note that high-quality batteries from reputable brands, such as Bosch, Shimano, Yamaha, and others, hardly ever catch fire.

Battery companies cutting corners can lead to defects that cause cells to expand and bulge

Electric bike batteries can explode, catch fire, or exhale toxic gases. This is due to the battery cells overheating, which can be caused by an internal fault, physical or electrical abuse, or extreme temperatures. The risk of this happening is higher with cheap e-bikes and low-quality batteries, often imported from China, due to a lower-quality manufacturing process. If battery companies cut corners or use cheap materials, there is a higher chance of defects that can cause the cells to expand and bulge. If they bulge, they can burst, which can also cause thermal runaway.

According to Leo Raudys, president and CEO of Call2Recycle, a nonprofit battery-recycling program, "You just have to remember, you get what you pay for. These batteries are highly engineered devices, and if you’re only spending a couple of hundred bucks on a battery, you’re probably getting one that’s cutting corners in a number of different places”.

In recent years, there has been a surge in incidents of electric bike battery fires. In the first half of 2023, the London Fire Brigade (LFB) was called to an e-bike or e-scooter fire once every two days, a 60% increase compared to the same period in 2022. In New York, six people died and 76 were injured in 2022 due to fires started by e-bike batteries. As a result, parking e-bikes in garages, caves, or apartments is forbidden in some condos worldwide.

While high-quality batteries from reputable brands are less likely to catch fire, even these companies can make mistakes. For example, one company had to recall 3 million devices because they kept exploding. Therefore, it is important to treat e-bike batteries with respect and care, and to visually inspect them for damage.

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