LiPo Fire Information

[Boyntonstu]

http://electricbikereport.com/electric-bike-battery-fires/

From the article:

There are about 220 million electric bikes in daily service around the globe, and fires are so rare as to attract international attention. (And keep in mind that cell phone batteries and computer batteries also, but rarely, catch fire.)

As an avid collector of ebike battery fire stories, I know of less than 20 such fires over a period of 20 years and more than 200 million ebikes in use.

Even so, there are a few recent stories in the media about fires that were caused by batteries on electric bicycles. Most of them at bike shops. And this raises questions.

The cause of these fires is often described as “battery for an electric bike that was charging”. (This reminds me of the family owned bike shop in the USA that burned down due to an electric drill on charge. That same family had a home burn due to another power tool on charge. Keep in mind that what is described here is applicable to all rechargeable batteries.) And often “charging over night”.

---------------------------------------------

In my situation I use a low current charger on 4 hour timer and I am sure that that it is off prior to going to sleep.

Does anyone have data on fireballs that occurred when not being charged or while riding?

https://www.electricbike.com/dangers/

"Mistreatment of lithium batteries
There have been numerous reports of lithium fires on electric bike rides, and also while the bike is charging. Most of these fires are on home built electric bikes with home made lithium battery packs consisting of strapped together R/C hobby lipo cells. Lithium batteries are very combustible and should be treated with a lot of respect and caution."

 

[brumbrum]

I doubt that there are any mass produced lithium polymer (lipo/lico) battery packs for ebikes even made. So it will be only the DIYer that uses them, and where there is diy there is always going to be error, misuse, stupidty, and accidents.

 

[Boyntonstu]

I doubt that there are any mass produced lithium polymer (lipo/lico) battery packs for ebikes even made. So it will be only the DIYer that uses them, and where there is diy there is always going to be error, misuse, stupidty, and accidents.

The Walmart Booster is as close as I could find as a mass produced 12V LiPo battery.

Everything in one battery package including a charge balance circuit, state of charge indicator, and a ac/dc low Amp charger.

No soldering and no cell handling.

Perhaps the equivalent of a SLA battery, but with its own charger.

 

[brumbrum]

I doubt that there are any mass produced lithium polymer (lipo/lico) battery packs for ebikes even made. So it will be only the DIYer that uses them, and where there is diy there is always going to be error, misuse, stupidty, and accidents.

The Walmart Booster is as close as I could find as a mass produced 12V LiPo battery.

Everything in one battery package including a charge balance circuit, state of charge indicator, and a ac/dc low Amp charger.

No soldering and no cell handling.

Perhaps the equivalent of a SLA battery, but with its own charger.

So are you saying you can buy a mass produced ebike that has a factory made lipo pack built in? 12v does not seem like much power for propelling a motor and wheel. We dont have Walmarts here in the U.K so i do not know what a walmart booster is.

 

[nutnspecial]

Ok, here's my take. People please correct me if I'm wrong.

Yep, and those powerpacks seem great in series for how they're being used. They have big bonuses over naked lipo (as mentioned), but the necessity to manually check cell levels remains important imo. Even if a pack has a bms for charge and discharge they should be monitored, because:

Lithium batteries are combustible. 'Lipo' is a unique lithium chemistry in that it offers high discharge rates with the downside of a lower thermal runaway. Both the lower internal resistance and lower thermal runaway equal more potential danger if overcharged or overdischarged. Lipo is also exclusively (afaik) in pouches which also increases volatility if unprotected- so yes overdischarging can come from physical cell damage too.

No batteries burst into flames for no reason, and although when charging is the most likely for a cell/cells to hit thermal runaway, it could happen on discharge or in storage -though each tends to be increasing rare regardless of how cell quality is monitored and dealt with.

Balance charging drastically reduces overcharging a pack or bad cell with the exception of user error (setting a charger over voltage/charge rate). If the cells are healthy, there is near zero risk of fire from discharge or storage provided discharge and storage are within accepted specs.

So it's good to know what the cells (and bms if equipped) are doing, across all three instances of use/disuse and to never be overly confident they wont catch fire seemingly randomly. IE, if you know all cells are good (dependable balanced discharge and charge with little help from you or other 'bms') you know they won't be catching fire just sitting there, or during spec'd charge/discharge.

So, know what the cells are doing to ascertain their continued dependablity, and don't use them or leave them in a place where you can't deal with a fire, in the event of a mistake/accident.

 

[Boyntonstu]

I doubt that there are any mass produced lithium polymer (lipo/lico) battery packs for ebikes even made. So it will be only the DIYer that uses them, and where there is diy there is always going to be error, misuse, stupidty, and accidents.

The Walmart Booster is as close as I could find as a mass produced 12V LiPo battery.

Everything in one battery package including a charge balance circuit, state of charge indicator, and a ac/dc low Amp charger.

No soldering and no cell handling.

Perhaps the equivalent of a SLA battery, but with its own charger.

So are you saying you can buy a mass produced ebike that has a factory made lipo pack built in? 12v does not seem like much power for propelling a motor and wheel. We dont have Walmarts here in the U.K so i do not know what a walmart booster is.

You should have something close to these wherever you live:

https://endless-sphere.com/forums/viewtopic.php?f=2&t=74924

 

[Boyntonstu]

Both the lower internal resistance and lower thermal runaway equal more potential danger if overcharged or overdischarged.

Overcharging with the supplied low current ac/dc charger and a 4 hour timer is not feasible.

Overdischarged is controlled by mild acceleration and by limiting max speed, and by keeping the discharge to about 3/4 full.

That is how I use the four in series 12V Walmart Boosters for a 48V battery.

 

[amberwolf]

There are a number of threads linked/listed in the various compilation threads by Bigmoose, about specific incidents. These and others are linked here:
https://endless-sphere.com/forums/viewtopic.php?f=14&t=69721
and there are probably others not yet linked there.

 

[Boyntonstu]

There are a number of threads linked/listed in the various compilation threads by Bigmoose, about specific incidents. These and others are linked here:
https://endless-sphere.com/forums/viewtopic.php?f=14&t=69721
and there are probably others not yet linked there.

As I read through the posts I noticed a few themes:

1> Chargers left overnight unattended. Solution: use a timer and a charge well below 1C.
2> Pilot error due to not paying attention such as connecting poss to neg. You know the solution.
3> Allowing a Lipo to fall and ignite. You know what not to do.
4> Building groups and connecting them in parallel. I use factory made 12V Walmart Boosters in series.


Some quotes:
The cause is still unknown but a damaged cell(s) in the pack that was being charged without monitoring is most likely.

I am concluding that it was an overcharged 3 series that caused the fire. The 4 series overcharged the 3 series and the 3 series had a thermal event.
I suppose there could have been a short , it was raining, but all the evidence is burnt up except the very intact power leads.

I have 15 packs I am playing with for many projects 3 spares besides that and 20 on order ATM. I was using the 15 packs for power for the drift trike and never made Y adapters for the ends of the packs I just left methods HVC/LVC boards in place to keep the 3 strings paralleled. On the YSR I made a set of Y adapters for the ends but I can not transfer them to the drift trikes so in my "Testing" on the drift trike I melted the traces on one parallel board at the end of my string and ran a single pack to 0v during hard current draw ~70 amps right down to 0v per cell. It must have happened early on because I Still had 4.2v in the cells on the other two packs that were originally paralleled to it. THIS IS MY FAULT 100%. I will not make the mistake again.

I combined my lipos into 20 ah 6s packs and I was loading them onto my bike and I managed to drop one. Two of the four batteries in the pack were damaged.


So my brother gets into ebikes... second time home alone charging with b6s and chooses nicd or nimh setting... charge for 4 hours... 24 hours later i check his battery and cells and gets confused. I see this: 4.6V


My bike is a DH Kona stinky deluxe full suspension, but is set up to ride on the street and bike paths only. I sometimes put the Lipo's in a bag that I fix inside the frame's triangle. You can see the pics on my build thread http://endless-sphere.com/forums/viewtopic.php?f=28&t=52029. Well that sudden drop actually compressed my back suspension enough to come squeeze my bag with 3 x 6 cell lipo's in it. It pierced one of the cells on one of the batteries.

Don't play with LiPo's, you may get burnt!

 

[Hillhater]

I doubt that there are any mass produced lithium polymer (lipo/lico) battery packs for ebikes even made. So it will be only the DIYer that uses them, and where there is diy there is always going to be error, misuse, stupidty, and accidents.

The Walmart Booster is as close as I could find as a mass produced 12V LiPo battery.
.

So are you saying you can buy a mass produced ebike that has a factory made lipo pack built in? 12v does not seem like much power for propelling a motor and wheel. We dont have Walmarts here in the U.K so i do not know what a walmart booster is.

Do you really think that all of those 220 million Ebike users made their own DIY battery packs ?
When was the last time you googled "Ebike" or looked on Ebay /Alexpress ?
Commercial lipo/lico packs are readily available and far outnumber the DIY packs you hear about.

 

[Alan B]

The RC folks have a lot more experience with Lipo than the ebiker's do, and they have a lot more data and burned cars, garages and houses.

Sometimes it is a bad setting on the charger (operator error), sometimes a charger fails (electronics is not perfect).

More often it is mechanical damage to the pack. The outer protection is very thin. There isn't much protection in many of the RC applications. They play hard and crash hard.

One thing good to do is mechanically inspect the Lipo for damage. The RC folks can do that easily since their packs are open to inspection, at least on the outside. Their procedure after a crash to pull it out and let it sit awhile and watch it. But cars, garages, shops and houses still get burned from time to time.

The car starting batteries are enclosed in plastic and rubber. We don't actually know how well supported and protected the Lipo is in the interior mounting. Vibration or dropping could impart damage to the pack inside with no way to inspect it. The Lipo in a $19 car starting battery might be well protected, but they have very little budget to do a top notch job between the lipo, the electronics, the charger, the USB regulator, the LED flashlight, the starting protection circuit, the battery clamps and the Nylon case and store packaging. I would like to see how protected it is in there. It may be great or it may be marginal. These packs were NOT designed to be series connected and they were never designed to be mounted to a vibrating, pounding bicycle.

We've seen RC Lipos fail when the circuit board at the end of the pack rubs against the pack. A difficult to inspect location.

We've seen 18650's fail and burn laptops due to metal flakes inside the cells when they were manufactured (Sony/Panasonic?). So it isn't limited to Lipos. The reliability of lithium batteries is more related to the quality of manufacturing and QC than any one other factor, I suspect. How much manufacturing quality and QC is there on a $800 cellphone? On a $3000 ebike? On a $600 laptop? On a $19 EverStart Car Starting Pack??

We've seen lipos fail sitting on a desk, never having been used. Probably damaged in shipment, a tiny puncture in the mylar bag. That's all that keeps them safely away from air and airborne moisture and failure. A very few thousandths of Mylar.

Be safe and have fun.

 

[motomech]

Ever buy a car or motorcycle or something on impluse and when you get home, you think, rather belatedly, "maybe I should research what I bought".
So you go on-line and are horrified that the first things to pop-up are complaints to Better Business and the like.
Like the guy who has put 3 transmissions in before 20,000 miles. You see dozens of folks with nothing but problems with the same model you were so proud of.
Then you settle down and wonder, "how many of these did Chevy or Dodge, or whomever make of this model?"
100, 000, 200,00? Maybe more?
Well, maybe you didn't buy a POS after all.
And then there the idiots that can break anything.
And if that guy went to the dealer for 3 transmissons, one right after another, he's an idiot anyway.
And then there are the haters and trolls posting.
It's the nature of the internet to make rare occurrences seem common place.

 

[dogman dan]

That is a very good article, written by a guy who is not just a dude with an opinion. Edward Benjamin has serious credibility.

http://electricbikereport.com/electric-bike-battery-fires/

One thing he did not mention, though he did stress "buy quality", is that most of the available e bike batteries that are lower priced lack UN 3835 certification. This means they are not good enough to pass in some cases, or they have not done the procedure to get the certification at the minimum.

So these uncertified batteries are illegal to ship, which is why the invoice says something like toys, or power supply, and there is no lithium battery labeling or hazmat shipping labeling on the box. This can be the case with both china, or vendors in your country. So ask if the battery will be shipped hazmat. If they aren't dinging you for hazmat shipping, likely it's shipped illegal. If the box doesn't have the lithium battery caution label on it when it comes, it was shipped illegal.

Don't trust those type the same as you would a certified battery.

Ever wonder why those walmart booster packs are the size they are, and not bigger? It's cuz they are small enough to ship legally without the UN cert. And hazmat shipping for a pack that small is not so costly.

 

[Boyntonstu]

If I can guess, charging is the most dangerous time for a LiPo fires.

Until I read http://electricbikereport.com/?s=fires I never heard of a bicycle charging rack that would allow a bike shop to wheel a smoking ebike outdoors.

Wow!

My guess is that 90% of fireballs occur during charging.

After the charger is removed and a few ours have passed, LiPo's appear to be fairly safe.

 

[Alan B]

If I can guess, charging is the most dangerous time for a LiPo fires.

Until I read http://electricbikereport.com/?s=fires I never heard of a bicycle charging rack that would allow a bike shop to wheel a smoking ebike outdoors.

Wow!

My guess is that 90% of fireballs occur during charging.

After the charger is removed and a few ours have passed, LiPo's appear to be fairly safe.

Charging is a dangerous time for batteries. Especially damaged ones.

Another 80 percent fireball later, after mechanical damage, some right away, some delayed. Without charging.

Charging a damaged battery does two things - it makes a fire more likely, and it gives it more stored energy to use in starting and sustaining the fire. Without charging a damaged battery may just smoke and go out rather than start a conflagration.

But sometimes they burn later, without charging.

Such as the Chevy Volt that burned days after the NHTSA crash tested it.

I talked to one bike shop owner who had a fire, and he said the fire started in an area with some non ebike chargers, and come computer peripherals like a printer. A power strip full of cheap power supplies, chargers and low cost electronics. There weren't any ebike batteries being charged and none in the area where the fire started. The fire department tried hard to figure out what started it and were unable to. The shop owner was convinced it was not an ebike battery fire.

One of our members here had a bike battery burn after it was punctured while rattling around in a bike basket. Mechanical damage followed by fireball. No charging involved.

You can imagine that an ebike shop would have a customer whose bike battery has some problem and they would be trying to charge it while diagnosing the problem, and have a fire. How detailed are the technician training and certifications for working on lithium batteries, especially larger complex ones, and actually doing repair? One battery was returned to the manufacturer and they found three parallel sections that were damaged and ruined on that daily driver pack. No fire on that one, but how far was it from that? That was 18650 cells, not lipo. Why was the BMS allowing it to be charged? To be used?

How would you safely approach working on a battery pack with a problem? How do you legally and safely ship it to the manufacturer? You probably cannot. One good approach is to only buy batteries from a local manufacturer who will repair them and whom you can drive to. When you buy a pack from far away you must be prepared to throw the pack out and take the loss.

What if it was a pack like this (there's no problem with this pack, but just assume that you had to work safely on something like it) - how would you approach that safely, who could you hire to do it and how much would that cost:

Since damaged lithium batteries can't be shipped, the local folks are the only ones who can work on them. But they're trained primarily in safe disposal, not analysis, welding and repair. They may be motivated by the cost of the pack to try to fix it rather than junk it, especially if they are on the hook for the warranty. But they probably aren't actually trained to do that.

I like Justin's approach - build packs from smaller (but well made) plug in sections that are each safer and more legal to ship or carry on planes. It is easier to diagnose and repair a problem this way.

The industry is headed for "lithium paranoia" and anytime something goes wrong with a few cells they'll destroy the whole battery, not fix it. The consumer will have to pay for it. They'll gladly sell you a new pack. This approach leads to $1000 plus battery packs.

That article seems to be excluding all non-commercial ebike batteries, so it isn't about our packs. Basically it is excluding most of the packs that have caught fire as well - the hoverboards and the RC applications. It is trying to make the commercial ebike batteries appear to be safe and promote the training which he apparently does for his income. Which is fine, but understand that there is a lot more out there to learn from than the limited experience of the commercial ebike manufacturers.

The Walmart Everstart batteries are not the batteries he is talking about here. He probably would not like them because they're pouches, not certified, and cheap imported products. They are more like the hoverboards than like the commercial ebike packs he is talking about.

Be safe and have fun,

 

[fechter]

If you search the forum for "battery fire" you will find many reports
https://endless-sphere.com/forums/search.php?st=0&sk=t&sd=d&sr=posts&keywords=++battery++fire

 

[Boyntonstu]

If I can guess, charging is the most dangerous time for a LiPo fires.

Until I read http://electricbikereport.com/?s=fires I never heard of a bicycle charging rack that would allow a bike shop to wheel a smoking ebike outdoors.

Wow!

My guess is that 90% of fireballs occur during charging.

After the charger is removed and a few ours have passed, LiPo's appear to be fairly safe.

Charging is a dangerous time for batteries. Especially damaged ones.

Another 80 percent fireball later, after mechanical damage, some right away, some delayed. Without charging.

Charging a damaged battery does two things - it makes a fire more likely, and it gives it more stored energy to use in starting and sustaining the fire. Without charging a damaged battery may just smoke and go out rather than start a conflagration.

But sometimes they burn later, without charging.

Such as the Chevy Volt that burned days after the NHTSA crash tested it.

I talked to one bike shop owner who had a fire, and he said the fire started in an area with some non ebike chargers, and come computer peripherals like a printer. A power strip full of cheap power supplies, chargers and low cost electronics. There weren't any ebike batteries being charged and none in the area where the fire started. The fire department tried hard to figure out what started it and were unable to. The shop owner was convinced it was not an ebike battery fire.

One of our members here had a bike battery burn after it was punctured while rattling around in a bike basket. Mechanical damage followed by fireball. No charging involved.

You can imagine that an ebike shop would have a customer whose bike battery has some problem and they would be trying to charge it while diagnosing the problem, and have a fire. How detailed are the technician training and certifications for working on lithium batteries, especially larger complex ones, and actually doing repair? One battery was returned to the manufacturer and they found three parallel sections that were damaged and ruined on that daily driver pack. No fire on that one, but how far was it from that? That was 18650 cells, not lipo. Why was the BMS allowing it to be charged? To be used?

How would you safely approach working on a battery pack with a problem? How do you legally and safely ship it to the manufacturer? You probably cannot. One good approach is to only buy batteries from a local manufacturer who will repair them and whom you can drive to. When you buy a pack from far away you must be prepared to throw the pack out and take the loss.

What if it was a pack like this (there's no problem with this pack, but just assume that you had to work safely on something like it) - how would you approach that safely, who could you hire to do it and how much would that cost:

Since damaged lithium batteries can't be shipped, the local folks are the only ones who can work on them. But they're trained primarily in safe disposal, not analysis, welding and repair. They may be motivated by the cost of the pack to try to fix it rather than junk it, especially if they are on the hook for the warranty. But they probably aren't actually trained to do that.

I like Justin's approach - build packs from smaller (but well made) plug in sections that are each safer and more legal to ship or carry on planes. It is easier to diagnose and repair a problem this way.

The industry is headed for "lithium paranoia" and anytime something goes wrong with a few cells they'll destroy the whole battery, not fix it. The consumer will have to pay for it. They'll gladly sell you a new pack. This approach leads to $1000 plus battery packs.

That article seems to be excluding all non-commercial ebike batteries, so it isn't about our packs. Basically it is excluding most of the packs that have caught fire as well - the hoverboards and the RC applications. It is trying to make the commercial ebike batteries appear to be safe and promote the training which he apparently does for his income. Which is fine, but understand that there is a lot more out there to learn from than the limited experience of the commercial ebike manufacturers.

The Walmart Everstart batteries are not the batteries he is talking about here. He probably would not like them because they're pouches, not certified, and cheap imported products. They are more like the hoverboards than like the commercial ebike packs he is talking about.

Be safe and have fun,

I am an inventor and if there is a problem, I always seek a solution.

A concept comes to mind: The battery is charged in a fireproof setting, preferably outdoors in a steel box enclosure.

[youtube]6M5ftkN9PtY[/youtube]

When you go for a ride you mount the battery onto a spring loaded connector.

This airplane safety system comes to mind: http://sportair.aero/6-chutes/whole-plane-parachutes/

On a bike we would not need anything more than an ejector handle.

If we detect a problem by sight or smell, we dump the battery as quickly and as safely as possible; hopefully after a stop.

Good riddance to a nightmare!

In my situation using the Walmart batteries, carrying them on a front frame mounted basket over the wheel instead of mounting them to the frame triangle would be an alternative.

Perhaps all LiPo batteries should be carried in steel boxes on and off the bike.

 

[Hillhater]

.....Perhaps all LiPo batteries should be carried in steel boxes on and off the bike.

That might make mobile phones, lap tops, Ipads, etc a little less portable !
But perhaps you are being a little paranoid and getting this all a little out of proportion.
I wouldnt recommend charging them under your bed whilst you are sleeping,...but i wouldnot let them prey on your mind quite so much.
A battery fire is much less likely than a fatal accident with a dumb car/truck/bus driver.....or, these days, ....a terrorist attack !

 

[motomech]

Amen,
I'm sure glad I started using Lipo years ago before I knew how dangerous it is

 

[Boyntonstu]

.....Perhaps all LiPo batteries should be carried in steel boxes on and off the bike.

That might make mobile phones, lap tops, Ipads, etc a little less portable !
But perhaps you are being a little paranoid and getting this all a little out of proportion.
I wouldnt recommend charging them under your bed whilst you are sleeping,...but i wouldnot let them prey on your mind quite so much.
A battery fire is much less likely than a fatal accident with a dumb car/truck/bus driver.....or, these days, ....a terrorist attack !

"Perhaps all LiPo batteries should be carried in steel boxes on and off the bike."


How did phones, laptops, ans ipads get included in this thread?

 

[amberwolf]

Just a guess, but perhaps because they contain LiPo batteries?

 

[friendly1uk]

Both my commercial bikes were lipo. Look at any suppliers website, it's very common indeed. Any commercial product with such chemistry contains a bms though. So very few burn. Here we have lots of fires because people choose not to use a bms. I mean.. why would you. It's cheaper easier and safer. Why would you want to do that when you could spend more on a more complex system that does less and causes about 100% of the fires. Sounds dull as hell to me. Charging your pack should be an event, with lots of wire swapping, sparks, the occasional explosion and a good Adrenalin rush. Some parameters to set and extra boxes to carry add to the fun. It seems a no brainer to me.

 

[Syonyk]

I doubt that there are any mass produced lithium polymer (lipo/lico) battery packs for ebikes even made.

Schwinn sold at least one. BP-L2410EH is the model number - it's very clearly pouch cells, and the person contacting me had them badly swollen to the point that they'd snapped the clips off the enclosure.

Lithium batteries are combustible. 'Lipo' is a unique lithium chemistry in that it offers high discharge rates with the downside of a lower thermal runaway. Both the lower internal resistance and lower thermal runaway equal more potential danger if overcharged or overdischarged. Lipo is also exclusively (afaik) in pouches which also increases volatility if unprotected- so yes overdischarging can come from physical cell damage too.

"Lipo" is not a unique lithium chemistry. It is commonly used to refer to pouch type cells - period. They use the same chemistries as any other lithium battery, though they do tend to be lithium cobalt oxide more often than not (power dense, energy dense, frighteningly low thermal runaway temperature). You can get LiFePO4 "lipo" cells as well, and I'd expect some NCA ones are on the market by now.

What if it was a pack like this (there's no problem with this pack, but just assume that you had to work safely on something like it) - how would you approach that safely, who could you hire to do it and how much would that cost:

Nope. There's almost certainly no way to do anything to that even faintly safely. Wouldn't touch it at all.

 

[docw009]

An e-bike shop in Madison, WI had a fire a few days ago.
http://www.channel3000.com/news/fire-reported-at-retail-building-on-odana-road/39040748

 

[Boyntonstu]

Keep Lipo's in a steel box and let them burn.

The ability of steel to contain the LiPo fire temperature without melting is a safe solution to prevent a fire from spreading.

[youtube]6M5ftkN9PtY[/youtube]