Battery Fires

Ray Winder

Pedelecer
Apr 13, 2017
102
28
71
North Yorks
I'm not an expert but it seems the battery fires while charging are an accelerating runaway process. Would it be so hard to make a power lead with a thermal power cut off which could be strapped to the battery with velcro when on charge?
Cut off point to be set at a safe level to try and arrest the problem early.
Probably not the perfect solution but another step towards safer charging.
I charge mine in the garage sitting the battery on one aluminium plate and the charger on another to act as heat sinks.
By the way I missed the announcement the DIY conversation was to be banned, when was that announcement?
 

Az.

Esteemed Pedelecer
Apr 27, 2022
2,092
932
Plymouth
We used to have them everywhere and then we started worrying about draughts and windows you could actually climb out of started disappearing.
So now people die in fires and have mold in house.
Now when I think of it, evacuation from my house through windows on first floor would be very problematic. I might need to do something about it.
 

Woosh

Trade Member
May 19, 2012
20,449
16,915
Southend on Sea
wooshbikes.co.uk
I'm not an expert but it seems the battery fires while charging are an accelerating runaway process. Would it be so hard to make a power lead with a thermal power cut off which could be strapped to the battery with velcro when on charge?
Cut off point to be set at a safe level to try and arrest the problem early.
Probably not the perfect solution but another step towards safer charging.
I charge mine in the garage sitting the battery on one aluminium plate and the charger on another to act as heat sinks.
By the way I missed the announcement the DIY conversation was to be banned, when was that announcement?
when the heat reaches the cable outside the case, the battery pack has already gone into thermal runaway. There is nothing anyone can do to stop the process and fire.
The weakpoint is usually one of the cells is faulty. There is nothing you can do to predict which one will short out. Fast charging or dodgy chargers can push weak cells over the edge.
The only practical solution for the moment is buying only from reputable retailers or force suppliers to have their batteries certificated.
 

Ghost1951

Esteemed Pedelecer
Jun 2, 2024
1,663
679
People might need to declare an interest here. I mean people who would have less competition and more profit if what they advocate came about.
 

Woosh

Trade Member
May 19, 2012
20,449
16,915
Southend on Sea
wooshbikes.co.uk
People might need to declare an interest here. I mean people who would have less competition and more profit if what they advocate came about.
I am one of about 1000 businesses selling e-bikes in the UK. I don't have any influence.
I think senior members of the forum should always err on the side of caution in their advice.
Battery fires are serious risks.
 
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Ray Winder

Pedelecer
Apr 13, 2017
102
28
71
North Yorks
when the heat reaches the cable outside the case, the battery pack has already gone into thermal runaway. There is nothing anyone can do to stop the process and fire.
The weakpoint is usually one of the cells is faulty. There is nothing you can do to predict which one will short out. Fast charging or dodgy chargers can push weak cells over the edge.
The only practical solution for the moment is buying only from reputable retailers or force suppliers to have their batteries certificated.
Of course I agree with the policy of buying reputable and feel that more should be done to close our market to disreputable.
Re the cut off I am sure the cable wont warm up much i was actually considering that it be mounted on a small aluminium patch which would be brought into full contact with the battery outer casing, my halfords suntour battery actually warms up very slightly when charging if it was set to trigger 4 or 5 degrees higher I'm sure it would give some protection.
 

Woosh

Trade Member
May 19, 2012
20,449
16,915
Southend on Sea
wooshbikes.co.uk
Of course I agree with the policy of buying reputable and feel that more should be done to close our market to disreputable.
Re the cut off I am sure the cable wont warm up much i was actually considering that it be mounted on a small aluminium patch which would be brought into full contact with the battery outer casing, my halfords suntour battery actually warms up very slightly when charging if it was set to trigger 4 or 5 degrees higher I'm sure it would give some protection.
even if you cut off the power to the charger, the chemicals inside the cells are the source of the fire when it's heated enough.
 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
20,980
8,565
61
West Sx RH
Have a care up there. Tree surgery is a very dangerous job and in my opinion, a young man's game.
Ladder tied lashed at top to tree. 5 ton rachet strap used to tie around large sections being cut and tied off lower down . Down on the ground one can safely lower the sections .
It is method and working safe that is important, rushing gets one nowhere.
 

AntonyC

Esteemed Pedelecer
Apr 5, 2022
332
144
Surrey
Fast charging or dodgy chargers can push weak cells over the edge.
The only practical solution for the moment is buying only from reputable retailers or force suppliers to have their batteries certificated.
The BMS is there to protect the cells, weak or otherwise, by cutting off. If charging causes a problem it's because the BMS isn't protecting the cells adequately. Charging does warm up cells but less than strong sunlight and much less than hard riding.

I think we should turn our attention to demanding good quality BMS, and restrict the sale of unprotected cell-packs into the consumer market, like we restrict knives, guns, poisons etc. (but not boxes of cells). As far as I can see 'overcharging' is being hyped for marketing reasons.
 
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AntonyC

Esteemed Pedelecer
Apr 5, 2022
332
144
Surrey
A lot of restrictions like PAT testing, EE waste disposal etc are supported through education and not fines.
It would be FAR FAR better to use education as the mechanism to reduce fires [...]

Attention to BMS quality would be a good thing. We all rely on that inexpensive little board to keep things safe. For such a cheap item, we may be over trusting them.
Agree 100%. Lithium ion cells have quite stringent requirements for stability, for example they tolerate a similar temperature range to a beeswax candle. The socio-economic aspect to fires needs public education to tackle them effectively.
 
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Ghost1951

Esteemed Pedelecer
Jun 2, 2024
1,663
679
Ladder tied lashed at top to tree. 5 ton rachet strap used to tie around large sections being cut and tied off lower down . Down on the ground one can safely lower the sections .
It is method and working safe that is important, rushing gets one nowhere.
I am sure that is true.

I have an eighty foot ash tree right outside my back door. It is just beginning to show signs of ash die back - at least there are a couple of small branches that look a bit sick. Most of the tree looks in its prime, but it is going to cost me a fortune to take down before too long. Worse still, there are power cables running very close. I had a quote for thousands of pounds last year. It will only have got bigger. When it does come down, I will have a life-time's fire wood if I can ever get it cut up.

You are very welcome to come and remove it. You can even keep the wood!

This photo was taken through a rooflight, so you can add at least 25 feet to estimate of size.

59111
 

Ghost1951

Esteemed Pedelecer
Jun 2, 2024
1,663
679
AntonyC said:
Agree 100%. Lithium ion cells have quite stringent requirements for stability, for example they tolerate a similar temperature range to a beeswax candle. The socio-economic aspect to fires needs public education to tackle them effectively
Apart from the volatile cathode and electrolyte made of organic solvents which burn, the separator which runs right through the many turns of the swiss roll construction is made of plastic that breaks down at about 130 C leading to a dead short throughout the battery cell with the release of very large amounts of energy. This technology is unstable and dangerous if it is not handled properly. Put into the hands of Deliveroo riders with 2 KW ebike motors that pull massive amperages from them, or young lads like the wheely artist I showed last week, and idiots who mix and match chargers, there is an issue here. Certifying battery construction might stop a tiny proportion of the fires, but I still think most of them are caused by stupid user behaviour. I am impressed by the statement made by saneagle that no one here has ever reported a battery fire. Why is that? Because they are aware of the dangerous practices that can make them explode.

Might as well ban the volatile kind and all go over to LiFePO4. It is pretty much impossible i think to get them to light up. Worst they seem to do is blow out some steam (which might contain obnoxious gasses) but they don't ignite even when people drive a nail right through them.

They do have less capacity for the same volume and weight though.
 
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flecc

Member
Oct 25, 2006
53,260
30,648
windows that actually open haven't been invented in most of the UK yet.
Full frame opening can be ordered as part of double glazing etc., here's one of my inward opening ones that can be cleaned both sides from indoors:

Inward opening full frame window.jpg
 

Peter.Bridge

Esteemed Pedelecer
Apr 19, 2023
1,328
609
People might need to declare an interest here. I mean people who would have less competition and more profit if what they advocate came about.
Well, not really, if suppliers had to go through a mandatory battery testing and certification process then we would have less of


I would definitely support it. It is more levelling on the playing field.

A "let the market decide" individualist approach doesn't take into account the cost to the state of dealing with battery fires - the consequences don't just fall on the individual that chooses the cheap dodgy battery.
 

AntonyC

Esteemed Pedelecer
Apr 5, 2022
332
144
Surrey
"stupid user behaviour..." A BMS cuts off if you pull too much current, or if high current persists making the cells too hot. It cuts off the wrong charger when current, voltage or temperature gets too high. It's there to take consumer grade misuse out of the equation, among other things, because until you know better stupidity is only ignorance. Get the BMS right and electrical issues go away.

Undoubtedly education would help massively both with sub-standard gear and because there's a limit to what physical protection can achieve for a battery left on a radiator or by a doorway etc. We need an education campaign and decent BMSes not fancy charger plugs, and I suspect sales restrictions on inadequately protected goods could work better, sooner and cheaper than certification.
 
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Ghost1951

Esteemed Pedelecer
Jun 2, 2024
1,663
679
Well, not really, if suppliers had to go through a mandatory battery testing and certification process then we would have less of


I would definitely support it. It is more levelling on the playing field.

A "let the market decide" individualist approach doesn't take into account the cost to the state of dealing with battery fires - the consequences don't just fall on the individual that chooses the cheap dodgy battery.
Well the product was removed from sale and that should solve the problem. Do we know of disasters caused by the product?

Part of my attitude to this issue is the impact on small, hard working and dedicated one man band e-bike converters like the one who converted my bike and made the battery. There is no way in Hell that he could get registered as a certified producer. He is too small. His business would be regulated out of existence in favour of larger, much more well resourced outfits.

And for what?

Would idiots stop hammering inadequate cells with their 2 kilowatt motors? No.

Would they stop sticking the first charge cable into their charge socket that they found when their old one blew a fuse - not bothering to wonder about its voltage or power output? No.

I doubt legislation would cut the rate of fires by 1%, because I don't think the fires are in general caused by bad manufacture, and if they are, Trading Standards will pick them up, force re-calls and order the UK online sellers to stop selling the product - as your post showed. That is what happened to UPP.
 

Ghost1951

Esteemed Pedelecer
Jun 2, 2024
1,663
679
If you think about it, why do we still allow people to buy matches, smoke in their houses, make chips in a chip pan, or God forbid - have an open fire or a wood burner? Where is the line

The state is not my nanny. I am responsible for what I do, and if I mess up and harm myself, it is nobody's fault but mine.
 

AntonyC

Esteemed Pedelecer
Apr 5, 2022
332
144
Surrey
His business would be regulated out of existence in favour of larger, much more well resourced outfits.
Regretably that's what the certification lobbying is all about, they even spell it out, look:

3 (1) (1) The Secretary of State must, within 12 months of the passing of this Act,
make regulations:
(b) Requiring that all micromobility vehicles have either
(i) a non-proprietary charging system with a communications protocol;
or
(ii) a proprietary charging system with a matched charger

This proposes one rule for the big brands who can afford proprietary tooling and another for the small players, who are ill placed to co-ordinate a common protocol, compatability with Bosch PowerStations and long term parts support, making their products less attractive.

Regulating charger matching serves no protective purpose... unless makers skimp on their BMS functionality which would make tampering easier and batteries less safe. What matching does is to tie in customers and allow bigger margins, but it also distracts from addressing fires effectively.
 

guerney

Esteemed Pedelecer
Sep 7, 2021
11,531
3,277
"Warwickshire Fire and Rescue Service said the e-bike was not on charge at the time but had started to not function properly."


...and that's why I keep my Ebike Battery Fire Expulserating PreTerminator™®©℠ on my battery whenever it's indoors, charging or not. The additional electricity cost is a small price to pay, considering. Tough luck if I'm not at home to hear the alarm horn go off, but at least my neighbours will wonder what the heck is going on. That horn sounding continously is extremely loud.


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/#post-708613

(Yes I know this needs a better video and sounds)
 
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