Many of the very problematic 'delivery franken bikes' being seen by the London Fire Brigade are not only dangerously cobbled together often with multiple batteries in parallel, but they are also worked very hard with big motors which heat up the batteries to dangerous levels and then they are being docked onto fast chargers which heat them up much more. This kind of very dangerous abuse is a world apart from sensible people using a kit of parts put together in a sensible way and used with a properly matched charger.

 

London Fire Brigade ran a special information event for delivery riders, which sort of backs up what I have been saying about some of their bikes. Many of us have seen these bikes - they are not normal e-bikes in my experience.

 

https://ebiketips.road.cc/content/news/amazon-and-deliveroo-have-recognised-the-part-they-can-play-when-it-comes-to-e-bike

What a proper battery standard would do, and perhaps UL2271 has already done in the US, is guarantee that the battery is safe no matter what the user does to it. (Perhaps excluding falling in a canal...remember that thread a while ago?)

 

The BMS should limit discharge and charge currents, monitor temperatures and each cell group voltage as well as total voltage, and turn off if any exceedance is detected. The design should have sufficient margin relative to absolute maximum cell capabilities, a quality of construction that is electrically and mechanically adequate, a level of water resistance suitable for outdoor use and so on. The charge port should not accept an incorrect charger voltage.

 

None of the above is difficult and when integrated into mass production facilities, need not add much cost.

 

The low standard and vulnerability to user error of cheap ebike batteries is unthinkable in the electric car world.

Without pictoral evidence for the London( Diy bike) fire , one can likely summise it was a typical 1kw lash up job .

Again the fact that the fire occured during the charge process one can only assume an incorrect charge procedure being used.

 

Practically every UK bike fire we hear about involves 1kw conversions with what one assumes a 48v or 52v battery. These guys simply have no idea of what they are doing especially with the charging process.

These guys simply have no idea of what they are doing especially with the charging process.

Nor should they have to. Consumer / user level goods need to be idiot proof.

I don't claim any electrical engineering qualifications , but I would be very careful if I was going to dismantle a battery. There was a chap on here a few days ago who accidentally punctured a cell while doing that which caused a fire, and he suffered burns to his hand and his leg which put him in hospital for a week.

 

 

I have an old Oven I made from a Smeg cooker so basically a double skin S/S steel box including the door with fire proof heat insulation in between the Two layers of metal .

 

I used to just stick it on a large Folker gas ring to cook baguettes at shows .

The fire officers where happy for me to use it I was just about to throw it on the scrap.

As it worked but not great with no automatic thermostat Very hands on .

but it got another Two years use out of a scrap 20 year old Smeg oven maybe it will live on !

 

I am thinking along the lines now of repurposing it for my planned work shop to charge battery’s in when I want to leave them unattended.

 

Although under the fire rated Gazebo in the garden is probably the best option when it’s not to cold .

 

Does a battery need to be in a vented place when Charging ?

 

As I just worked out my battery from an ex display Bird bike has internal problems so I may just try harvest any decent cells , and fix the one a blew in my other post.

 

Just need to design a way of getting 240 electric supply into it that will also contain a fire a very hot one .

I will do a post on it and see what you experienced guys think .

 

No what I am getting at is a sealed fire proof box any use for charging battery’s ?

 

I e . Do they need air flow around them so they do not over heat or can an old oven work as a safe place to charge things that may be a bit suspect , or if you wanted to put 5v through a cell group then go out and leave it say for 5 to six hours or less Or over night .

 

or would you need to vent say through an old chimney stack ?

 

So if it did catch fire any fire would be contained And any smoke could go out through an old chimney . Which would then also be an air flow vent

No what I am getting at is a sealed fire proof box any use for charging battery’s ?

 

No. You would be literally making a bomb. The more you try to contain gasses the bigger explosion you will get.

 

or would you need to vent say through an old chimney stack ?

 

So if it did catch fire any fire would be contained And any smoke could go out through an old chimney . Which would then also be an air flow vent

 

Smoke is toxic and flammable. Chimney won't remove all of it , but it is better than nothing.

Your approach is back to front, and in a commercial setting potentially unlawful.

 

Known risks must be sufficiently mitigated, and most of that is in designing out the chances of them occurring.

 

Instead of containing a risky procedure in a fire proof box, eliminate the risky procedure!

 

That might be to implement equipment that cannot produce the dangerous situation. In the example of charging an individual cell group, the charging equipment would need to incorporate as a minimum automatic disconnection to avoid exceeding safe voltage, and better if it also monitored temperature and current.

 

Or in a commercial setting, treat a severely depleted or unbalanced battery as dangerous scrap, and eliminate the procedure altogether. Where's the liability if such a 'recovered' battery goes on to cause a problem? I wouldn't want it.

 

A fireproof box as a secondary measure does no harm, but is no substitute for proper risk controls.

The news story say's the bike was bought from an online market place (what ever that is) face book or Ebay so likely a used item ???

The bike as we know is a converted push bike .

The chances of a mismatched battery /charger comes to light in my mind as well as the user not being familiar with safe charging practices or matched component parts.

Where's the liability if such a battery goes on to cause a problem? I wouldn't want it.

 

I would not want such a battery either.

 

If the battery were 'recovered' by someone very experienced at recovering batteries, then maybe.

 

But how often do people, who are clearly beginners, go onto public Internet forums and get advice on how to recover a battery .............

I would not want such a battery either.

 

If the battery were 'recovered' by someone very experienced at recovering batteries, then maybe.

 

But how often do people, who are clearly beginners, go onto public Internet forums and get advice on how to recover a battery .............

There is one on this very thread that does yet realise how close he came to a serious fire by bypassing the BMS (based on 'knowledge' gained here) and is now talking about a commercial venture repairing batteries. I warned him in another thread but he seems determined to either burn his house down or cause an explosion. This stuff is NOT a fire risk, it is an EXPLOSION risk and not to be treated lightly.

We currently have a drink driving campaign going on here which talks about 1000 times it was fine but the 1001st ended in disaster.

 

But how often do people, who are clearly beginners, go onto public Internet forums and get advice on how to recover a battery .............

 

 

 

There is one on this very thread that does yet realise how close he came to a serious fire by bypassing the BMS (based on 'knowledge' gained here) and is now talking about a commercial venture repairing batteries. I warned him in another thread but he seems determined to either burn his house down or cause an explosion. This stuff is NOT a fire risk, it is an EXPLOSION risk and not to be treated lightly.

 

We currently have a drink driving campaign going on here which talks about 1000 times it was fine but the 1001st ended in disaster.

 

 

 

Sorry 36 v

 

Damm just as I thought it was charging as it came up to fully charge I heard a small crack sound and now one cell group has gone down .

 

Black RS white Red LS yellow is now 0 volts

 

 

 

Advice is better than no advice. Personally, as a non-expert, that huge difference in cell bank voltage would have stopped me in my tracks. Excessive charging temperature within the case would probably have set off my alarm, before that hot cell/cell group cracked:

 

 

https://www.pedelecs.co.uk/forum/threads/home-ruination-by-ebike-battery-fire-expulserating-preterminator%E2%84%A2%C2%AE%C2%A9%E2%84%A0.46934/

 

 

Presumably he switched the charger off when he heard the crack, and had he not read forum threads and received advice, that "small crack sound" would have occurred while the battery pack was inside the case, probably gone unnoticed while the battery continued to charge, which might have gone on to damage adjacent cells starting a chain reaction, leading to more ignitable smoke and explosion? At least that dude still has nostril hairs, eyebrows, possibly a full head of hair, and a house they can all live in.

Edited December 22, 20241 yr by guerney

A couple of thermistors isn't going to cost much but I somehow doubt that is the route that will be followed / legislated.

 

As far as I can tell, there's a dearth of detail in the new guidelines, and I reckon this is because there wasn't much agreement between the vested interests involved, which I believe will lead to them doing whatever the heck they want with regard to locking everything down to hell and making ebikes unrepairable. Repairability isn't mentioned at all! Roll on fast e-fashion! Our food, air and water will be further poisoned by ewaste and the oceans will become gigantic extinction level event causing cesspools. :mad::mad::mad::mad::mad:

 

https://www.gov.uk/guidance/statutory-guidelines-on-lithium-ion-battery-safety-for-e-bikes

Edited December 21, 20241 yr by guerney

Advice is better than no advice.

 

For sure it is.

 

And most often the advice should be, you dont know enough about the subject, you cannot become an expert by reading a couple of internet posts, so dont even attempt the repair.

 

Yet still the 'advice' is given.

There is one on this very thread that does yet realise how close he came to a serious fire by bypassing the BMS (based on 'knowledge' gained here) and is now talking about a commercial venture repairing batteries.

 

Well asking advice is fine.

 

But you cannot redact the appropriate advice to a couple of sentences in an Internet post, yet some people try.

 

If you were buying a 'repaired' battery, most people might might expect that the person doing the repair had some formal qualifications or certifications in electrics\electronics.

For sure it is.

 

And most often the advice should be, you dont know enough about the subject, you cannot become an expert by reading a couple of internet posts, so dont even attempt the repair.

 

Yet still the 'advice' is given.

I have bought a job lot of Carrera bikes and parts from an online auction .

 

The risk is on a whole other scale vs a joblot of broken ICE dirt bikes to repair and resell. I reckon that battery pack would have been charged, overheated, smoked and exploded, if he hadn't received advice and opened the battery pack. Sadly, time can't yet be rewound to confirm. If time ever could be, we'd already know how.

 

BTW despite the ban, second hand ebikes and batteries are still being sold by individuals on ebay.

Edited December 21, 20241 yr by guerney

There is one on this very thread that does yet realise how close he came to a serious fire by bypassing the BMS (based on 'knowledge' gained here)

He didn't do it based on knowledge gained here. He was told how to check the battery and how to balance it, but he chose to charge it through the output terminals, presumably because he read that somewhere else or just invented that procedure himself. Nobody advised him to do that, and, to my knowledge, nobody has ever advised anybody to do that on this forum without explaining the risks and how to mitigate them.

He didn't do it based on knowledge gained here. He was told how to check the battery and how to balance it, but he chose to charge it through the output terminals, presumably because he read that somewhere else or just invented that procedure himself. Nobody advised him to do that, and, to my knowledge, nobody has ever advised anybody to do that on this forum without explaining the risks and how to mitigate them.

While he may not ha e been instructed to completely bypass the BMS to charge the whole bank he had been told to charge individual cell groups directly by bypassing the BMS. A couple of posts later he has got bored of waiting for the individual groups to charge so decided to do the rest all in one go. Some of the cell groups appear to have a higher voltage than others leading to the fortunately benign incident. If he continues buying piles of shite and not understanding what he is doing and not following the sometimes very technical advice given here to the letter somone is going to get badly hurt.

My guess is, he knows more about balloons than I do, but not as much as [mention=9614]Nealh[/mention].

 

 

 

 

I sometimes wonder how many have a go battery repair heroes don't post about how they burned their houses down and killed their families, out of fear of embarrassment and barrage of "I told you so"s. I can't wait for the first one.

they wont have any internet will they and be in prison for being a twat

While he may not ha e been instructed to completely bypass the BMS to charge the whole bank he had been told to charge individual cell groups directly by bypassing the BMS. A couple of posts later he has got bored of waiting for the individual groups to charge so decided to do the rest all in one go. Some of the cell groups appear to have a higher voltage than others leading to the fortunately benign incident. If he continues buying piles of shite and not understanding what he is doing and not following the sometimes very technical advice given here to the letter somone is going to get badly hurt.

Somebody explained to him exactly how to balance individual cells and how to monitor them so that there would be no issues. There's nothing wrong with that. You can't blame whoever that was for the guy ignoring the advice and doing his own thing.

 

It's basically the same as somebody asking how to store their battery. They'd be advised to keep it in a cool stable situation, but instead, they put it in an oven and it blew up when somebody turned on the oven to pre-heat it for the Sunday roast. Your argument is that nobody should have advised him to store it in case he ignored the advice and did his own thing. Storing batteries is dangerous if you don't do it right, so is using one, and so is having one. Maybe we should advise everyone not to get an ebike because they're dangerous. In fact never mind owning an ebike, riding any bike is complicated and dangerous if you don't get it right, so keep away from them. Is that it?

If you were buying a 'repaired' battery, most people might might expect that the person doing the repair had some formal qualifications or certifications in electrics\electronics.

 

My guess is, he knows more about balloons than I do, but not as much as [mention=9614]Nealh[/mention].

 

Provided people follow expert instructions to the letter, I'm not entirely certain electrics/electronics qualifications or certifications are strictly necessary to attempt diagnosing a battery fault. Apart from assembling and "repairing" PCs and servers (ie diassembly and reassembly, no soldering of components involved), I myself have made a point of never mucking about with physical electronics and getting my hands dirty... until I bought a Bafang BBS01B conversion kit, because I wanted an ebike which had a reasonable chance of repairing myself, rather than a locked down to hell bastard of a device (increasingly de rigueur these days), functionality of some or all of which, could be killed remotely by the manufacturer whenever they wanted to make me spend even more money than they charge via agents for servicing - a disgusting state of affairs nearly all of us are now certain to end up with, thanks to those intentionally vague new government guidelines manfacturers have cooked up in collusion. There's no mention of repairability, or use of an common open standard for comms. I never had to do much practical electrickery with O and A level physics, and aside from computing modules for my joint honours degree (lots of typing and scribbling with pencils was the extent of practical stuff, nothing that got my fingers substantially dirty), everything I studied at university was something hardly anyone studies (wasn't one of the soggy sciences - those lead to dirty hands), yet as you know I was finally forced to learn how to solder thick wires together, with help from you and others on the forum (cheers!), and my hands are now often dirty. When my battery goes titsup, I'll certainly seek advice on the forum and attempt diagnosis of the problem, but if cell bank voltages show very wide variation, I would probably attempt to balance (I've bought at least two types of lithum-ion cell charging module, ready for the day) and soon thereafter most likely abandon the battery, buy a new one.

 

 

While he may not ha e been instructed to completely bypass the BMS to charge the whole bank he had been told to charge individual cell groups directly by bypassing the BMS. A couple of posts later he has got bored of waiting for the individual groups to charge so decided to do the rest all in one go.

 

I've seen that happen here before - this isn't a 24 hour live chat service desk run by some commercial concern manned by hired experts, and impatient people jump the gun leading to problems.

 

 

If he continues buying piles of shite and not understanding what he is doing and not following the sometimes very technical advice given here to the letter somone is going to get badly hurt.

 

I sometimes wonder how many have a go battery repair heroes don't post about how they burned their houses down killing their families and pets, out of fear of embarrassment and barrage of "I told you so"s. I can't wait for the first one.

Edited December 22, 20241 yr by guerney

Advice / instructions must always be accompanied by sufficient safety warnings, including 'don't do it if you don't understand'.

 

As with all good info, the 'why' as well as the 'what'.

 

I think that was the case on this occasion.

Three injured after e-bike fire traps them inside Plymouth home

The casualties suffered burns and smoke inhalation

https://www.plymouthherald.co.uk/news/plymouth-news/three-injured-after-e-bike-9812101

He didn't do it based on knowledge gained here. He was told how to check the battery and how to balance it, but he chose to charge it through the output terminals, presumably because he read that somewhere else or just invented that procedure himself. Nobody advised him to do that, and, to my knowledge, nobody has ever advised anybody to do that on this forum without explaining the risks and how to mitigate them.

 

yes no one advised me , when the battery was nearly charged as Mathew instructed , I realised we now had voltage at the secondary terminal s that go to the battery , whilst still not getting any voltage at the first input and discharge terminals.

 

I was sitting with it when put the main charger on just for a few minutes, then heard the crack , turned it off and disconnected it .

and monitoring the voltage the set that fused or blew was at 4.5V so just one volt higher than the rest.

 

but as the charge was still going into the BMS it must be knackard ?

 

Hence my questions on how to make a safe place to do this sort of thing if something goes wrong.

 

or how is it supposed to be done in a commercial battery repair shop ?

 

That said any battery charging is a risk then even expensive branded things so if we think about Risk Assesment something I have done many times then really do we want to charge any battery in our homes unattended without some sort of emergency procedures in place ?

 

After all as soon as One goes out on a bike or car there is risk.

 

One of the other posts regarding getting round £500 quid Carrera battery handshake does work .

 

Attached is a motor test set using KT , Suntours combination , which I whished I had set up a few days ago .

 

I just had to refund a guy on e bay for for a Suntour motor and wheel which I could not test after buying a job lot of ex display bikes

 

this one works fine with a throttle .

 

but I would still like to put an after market BMS in this battery as I can no longer sell it on e bay .

 

I have always liked playing with fire !

 

taking all your good advise on board guys thanks , but I will be learning how to build batteries and fix other components I enjoy the challenge.

 

hope you will still help ?

Oh and it went crack just as the charger went from red to green practically simultaneously.

 

 

That said any battery charging is a risk then even expensive branded things so if we think about Risk Assesment something I have done many times then really do we want to charge any battery in our homes unattended without some sort of emergency procedures in place ?

 

I don't. I don't charge at home and don't keep e-bike batteries at home.

 

I have always liked playing with fire !

 

Except when you sell repaired bikes, it is not you who is playing with fire.