Ebike battery fire

guerney

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I'm amazed at the speed this electric bike battery goes up in flames. I'll sniff my battery regularly from now on. Bag battery:




Man narrowly avoids fireball after e-bike explodes in block of flats



London Fire Brigade issues warning after exploding e-bike caught on camera

 
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guerney

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The battery bag has a hole, through which smoke is being forced out, which might have let rain in? He blew the bloody Dawes up.

51783
 
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guerney

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Great idea. Keep your face as close as possible and camera on. This will go viral on Tik Tok when battery explodes.

Edit: ;)
I need an electronic nose to sniff out imminent battery fire - this guy had ample warning, and enough time to move the bike using a lift down to the lobby.
 

Bonzo Banana

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Looks like some sort of bodge up as the flames are coming from the bag it seems yet the model in question has an internal battery in in the frame I think. So some DIY customisation going on here.
 

guerney

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Looks like some sort of bodge up as the flames are coming from the bag it seems yet the model in question has an internal battery in in the frame I think. So some DIY customisation going on here.
Dawes ARC II? Arced here too. Is that a mid drive motor on that bike, plus a rear hub motor?

 
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guerney

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If this is a mid-motor, IMHO it looks too small to be a Bafang. Did this battery blow up because this guy was using it to power a TSDZ2 plus a hub motor? Or perhaps he was using two independent systems, both hub and mid-drive, with two batteries, with the other battery in the frame? As usual, there is not enough detail in news reporting about ebike fires.


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saneagle

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Batteries in bags are just a very bad idea. People don't realise that the battery is bouncing up and down inside the bag. All it takes is one wire to rub through the insulation to get a fire-bomb. It makes little difference whether you have the battery hanging from the cross-bar, on a rack or in a pannier, though pannier is probably the worse because not only do you get constant movement of the wires, but it bashes against the frame too. The battery and every wire needs to be properly restrained and protected from ever touching another wire.

The majority of battery fires we see in the media and anywhere else involve batteries in bags.
 
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guerney

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Batteries in bags are just a very bad idea. People don't realise that the battery is bouncing up and down inside the bag. All it takes is one wire to rub through the insulation to get a fire-bomb. It makes little difference whether you have the battery hanging from the cross-bar, on a rack or in a pannier, though pannier is probably the worse because not only do you get constant movement of the wires, but it bashes against the frame too. The battery and every wire needs to be properly restrained and protected from ever touching another wire.

The majority of battery fires we see in the media and anywhere else involve batteries in bags.
Who are these "Experts" the media keep consulting, who say pretty much the same things every time? The battery has clearly bounced around dangerously inside the bag enough to wear through making at least one hole.


51789
 
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Bikes4two

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Batteries in bags are just a very bad idea. People don't realise that the battery is bouncing up and down inside the bag. All it takes is one wire to rub through the insulation to get a fire-bomb.
A badly made battery what ever it is contained in is not a good thing but of course a bag battery is more prone to having problems if not we'll built.

But with the right build quality and bag then a bag battery is going to be OK in my book.

I wonder what @Woosh might have to say on this seeing as he sells bag batteries and no doubt did some risk assessment on the product?

I'm coming up to a 1,000 miles on my self built handlebar mounted bag battery and I am going to partly dis-assembly it soon to check how it is fairing.

The comment about one wire wearing through to create a fire bomb is not true - it would have to be a particular pair of wires to lead to this, not just any old wire amongst the many to be found in a battery pack and careful design and build can greatly reduce even that risk.
 

saneagle

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A badly made battery what ever it is contained in is not a good thing but of course a bag battery is more prone to having problems if not we'll built.

But with the right build quality and bag then a bag battery is going to be OK in my book.

I wonder what @Woosh might have to say on this seeing as he sells bag batteries and no doubt did some risk assessment on the product?

I'm coming up to a 1,000 miles on my self built handlebar mounted bag battery and I am going to partly dis-assembly it soon to check how it is fairing.

The comment about one wire wearing through to create a fire bomb is not true - it would have to be a particular pair of wires to lead to this, not just any old wire amongst the many to be found in a battery pack and careful design and build can greatly reduce even that risk.
I'm not normally one to do scaremongering, but encouraging people to gamble on which wires are going to touch? Really?
 

guerney

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Are soggy batteries more likely to blow up?
 

Woosh

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A badly made battery what ever it is contained in is not a good thing but of course a bag battery is more prone to having problems if not we'll built.

But with the right build quality and bag then a bag battery is going to be OK in my book.

I wonder what @Woosh might have to say on this seeing as he sells bag batteries and no doubt did some risk assessment on the product?

I'm coming up to a 1,000 miles on my self built handlebar mounted bag battery and I am going to partly dis-assembly it soon to check how it is fairing.

The comment about one wire wearing through to create a fire bomb is not true - it would have to be a particular pair of wires to lead to this, not just any old wire amongst the many to be found in a battery pack and careful design and build can greatly reduce even that risk.
Pouch cells can explode because they don't have built-in anti explosion device and there is no air gaps between the pouches. When a cell is shorted, it will short adjacent cells and set off an explosion.
Cylindrical cells have anti explosion, steel jackets and placed inside plastic separators. They burn individually, give a lot of smoke and heat but not much fire and don't explode.
Don't buy batteries built with cheap pouch cells.
The bag battery is more susceptible to water damage than traditional plastic casings but the fire risk is the same.
 

StuartsProjects

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Pouch cells can explode because they don't have built-in anti explosion device and there is no air gaps between the pouches. When a cell is shorted, it will short adjacent cells and set off an explosion.
Indeed they can, seen a small one, 3S1P 1200mAhr explode into a fireball, medicine ball size.

Surely people are not daft enough to use el-cheap LiPo style batteries for eBike batteries ?
 

sjpt

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Surely people are not daft enough to use el-cheap LiPo style batteries for eBike batteries ?
If they are cheap people will buy them, whether suitable/safe or not.
 

Bikes4two

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Another ebike/battery fire report to scare the pants off the ill-informed.

When there are fires from well made, quality batteries that have been kept charged with quality chargers and not abused in the many ways that people do, then I'll worry, but in the meantime I'll be attributing such reports to those journalists (and forum posters) that are always looking for an attention grabbing headline.
 

guerney

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Another ebike/battery fire report to scare the pants off the ill-informed.

When there are fires from well made, quality batteries that have been kept charged with quality chargers and not abused in the many ways that people do, then I'll worry, but in the meantime I'll be attributing such reports to those journalists (and forum posters) that are always looking for an attention grabbing headline.
This was worth posting, because of useful information you and other forum members have posted about batteries, and I'm always willing to learn more. Anyone on this forum has the facility to ignore my posts if they wish, using the "Ignore" feature.
 
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guerney

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Thousands of unsafe e-bikes and e-scooters are being seized at UK ports

May 24 2023


 
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guerney

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Ask Rocio: How deadly goods sold online are putting lives at risk
Fire brigades warn that e-Scooters are ‘fastest-growing fire risk’ but vital government product safety review is delayed

"Clearly, putting the public at risk like this isn’t acceptable. The Office for Product Safety and Standards (OPSS), which currently operates out of the Department for Business and Trade (DBT), has conducted a review into the issue, but still we await its publication, meaning more needless delay on making our product safety regime fit for purpose. "


 

StuartsProjects

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I'm amazed at the speed this electric bike battery goes up in flames. I'll sniff my battery regularly from now on.
There has been comments about pouch batteries.

I was charging a 3S 1300mAhr LiPo, used in one of my RC model planes.

From hearing a noise, like plastic stretching, and there was no smoke or smell, and it exploding in a fireball was maybe 5 seconds.
Thousands of unsafe e-bikes and e-scooters are being seized at UK ports

May 24 2023


About time ?
 
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