News Article

Underrated E-Bike Battery Fire Hazards Call for Attention on Safe Storage


DOETINCHEM, the Netherlands – Concerns over Lithium-Ion batteries exist for a long time already. However, due to what recently happened at a Dutch dealer where an e-bike battery spontaneously caught fire causing severe damages is increasing such worries. It’s high time to turn to a fire safety engineering expert for advice and tips on the storage of e-bike batteries.

Underrated E-Bike Battery Fire Hazards Call for Attention on Safe Storage
Handle e-bike batteries with care. Like by charging batteries used in e-bikes on display in showrooms and the ones in bikes in stock to up to only 30%. – Photos Bike Europe

A security camera at Auke Tweewielers in Ede, the Netherlands precisely shows what happens when a lithium-ion battery catches fire.

What starts with a few sparks develops into an ever-increasing fire as more and more battery cells ignite and emit flammable and toxic gases. How to prevent and to handle such fires is explained by fire safety engineer and battery safety expert Rob Overdijkink.

Safety aspects

Following the fire at Auke Tweewielers Rob Overdijkink came to inspect the store, the workshop and the place where bicycles and e-bikes are stored. He advised the dealer on redesigning both the storing of the to be repaired e-bikes as well as his battery storage room. Overdijkink has extensive experience with electric vehicles and everything that comes with it. He is consultant and owner of FSE Support (Fire Safety Engineering) and advises on safety aspects concerning electric cars, their lithium batteries and on associated fire protection.

‘Rather unreliable, rather explosive’

Overdijkink compares Lithium-Ion batteries, the most commonly used batteries in e-bikes with North Korean leader Kim Jong-un. “Rather unreliable, rather explosive. You are never sure if or when they will explode. And when they do, you have a big problem.”
He sums up examples of damages caused by exploding lithium-ion batteries. Like at a bike dealer in Hannover, Germany where a battery fire accounted for a loss of half a million euro. Or at another German city where a historic building burned down due to an exploding battery, causing a damage of 5 million euro.

Cylindrical cells with standard safety features

Overdijkink: “Fortunately, in recent years the prismatic cells in batteries have been replaced by the now mostly used and much safer round or cylindrical cells which have more standard safety features.” But he still advises to also handle them with care. Like by charging batteries used in e-bikes on display in showrooms and the ones in bikes in stock to up to only 30%. “This percentage is the most secure. Moreover, aging will be about zero.”

Battery storage container

For demonstration e-bikes; the to-be-delivered ones and the to be repaired bikes, he advises dealers to purchase a suitable battery storage container or room that has an integrated automatic extinguishing system. Such systems are equipped with temperature and/or smoke sensors which 24/7 are able to detect heat and/or smoke and eventually activate the fire extinguishing automatically as well as cooling the container. With that more damage can be significantly reduced.

Insurance companies too noticed that e-bike batteries are posing an increased risk to companies and dealers that stock them. Insurers can require additional measures for safe storage and handling by for instance fire extinguishers.

Battery transport

Next to storage also the transport of e-bike batteries presents a safety issue. Such issues are tackled by the “Accord européen relatif au transport international de marchandises Dangereuses par Route”. This is referred to as ADR and is the pan-European treaty for the international transport of dangerous goods by road. But there’s more with regard to ADR. In for instance the Netherlands it stipulates that a prevention officer is to be appointed at companies where dangerous goods such as e-bike batteries are present. However, there are no rules requiring this to be an ADR-trained employee. In companies with a maximum of 25 employees, the director may take this task upon himself.

Battery Safety Tips

  • E-bike battery charging always in staff presence; not at night.
  • If a battery is dropped preventive check is recommended. Check with the owner if the bike including battery has ever been dropped.
  • Do NOT try to put out battery fires with classic extinguishing agents such as CO2, powder or foam.
  • Put out fires with abundance of water.
  • Covering and extinguishing an ‘inflated’ battery can also be done with sand.
  • Never immerse burning batteries in water. This produces chemical reaction which generates hydrogen gas; together with oxygen this forms very explosive gas.
  • Putting out battery fires is most effective in closed off space with dry aerosol.
  • Refurbishing batteries only advisable if refurbishing company complies with all the rules. Partial cell replacement in existing battery is strongly discouraged. After refurbishing, the battery must (again) comply with EN50604 standard and UN 38.3 standard.
  • Purchase special battery storage container with integrated certified lithium extinguishing system.


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