Who has First Hand experienced a LiPo fire ?

[Wingman]

You mean like this?😄

 

 

Edited July 1, 2023 by Wingman

[Phil Green]

51 minutes ago, KenC said:

Can someone tell me where they get ammo boxes from . 

Mine came from a local car-boot sale, some random bloke had a mountain of them. Nice shiney ones £20, scratched £15, battered but mechanically perfectly ok £10

BTW some advise drilling holes - dont!

[Graham Bowers]

8 minutes ago, Wingman said:

You mean like this?😄

 

Saw somebody giving that sort of treatment to a well puffed lipo at the field last weekend. I think it arrived in a "job-lot" however once eyeballed, nobody fancied putting it in the car to take home for disposal.

 

The protagonist had the forethought to use a rake as his weapon of choice.................

[ron evans]

Back in the last century I managed to drop a 7 cell nicad pack onto hard ground. The insulation looked undamaged but within a few seconds the pack got very hot and burned the insulation away, fizzing as it went. Not as bad as a lipo fire, but would have given a nasty burn if carried in the pocket.

 

In contrast, some years later I was flying a foam MX2 and when pulling hard into the vertical the 3s 2200 pack came out and they both went in from about 30 ft.

The MX2 was a mess and I fully expected the lipo to burst into flames, but it didn't despite being bent like a banana.

The pack was left to mellow for a few hours and I eventually took it home in the car ( a short journey, but in hindsight not the wisest thing to do ).

I cycled the pack a number of times and briefly ran it at 22a in the repaired MX2, but never used it again in the air.

I think that tough pack was a Gens Ace.

 

Ron

[leccyflyer]

1 hour ago, KenC said:

Can someone tell me where they get ammo boxes from . From my distant memories all our 7.62 was in wooden boxes with  sealed metal inners that were there more to keep things out.  I guess water might be a bit like it is when dealing with phosphorus , it stops it until the air is returned. 

No, that isn't really the case. There is sufficient oxygen in the electrolyte of the lipo battery to permit it to burn without access to atmospheric oxygen. That's what makes lipo fires so tricky to put out and that's why you can find videos of them burning with a vigorous flame underwater, That water can certainly help. in that it can help from the surrounding materials catching light as well, but it won't put the lipo fire itself out.

[Engine Doctor]

Compare a lipo or li- ion fire to an oxycetalene torch . Once lit you can put that under water and it will continue to burn happily due to the oxgen and gas  mix under pressure. Lipos or li- ion also produce combustible gases underpressure ignited  by battery components shorting that have enough oxygen to burn without the need of atmospheric oxygen.

If enough water or an extiguishing agent could get to the source of the heat and then it could probably evenntually extinguish the fire . Even a high pressure jet of water wont penetrate the plastic lipo or metal li-ion cases so they burn until the have exhausted their fuel.; hence fire brigades inability to put out EV fires , they just protect surrounding risk and let the EV burn out.

As for keeping gloves handy , dont be tempted. A lipo can expell a jet of hot or burning gas long enough to hit your face causing serious injury. Let it burn and if possible just protect the surounding area . 

[Neil James]

I’ve never had one myself but several years ago someone turned up at our flying site with an electric glider in the back of his car with the battery already installed. As he was unloading smoke was spotted so the glider was quickly yanked out of the car and onto the grass where the smoke turned into a cheery conflagration, destroying his model! I think he was very lucky not to lose his car.

On the other hand, I had a large electric glider crash into the tarmac sufficiently hard to mangle the battery but there was no subsequent temperature increase or flames.  

I carry my LiPo batteries in a containment bag on the passenger seat of the van so if anything happens I can drop the window and sling the whole lot outside.

[Zflyer]

Regarding ammo boxes. The odd few appear in model shops, car boot sales, outdoor exhibitions i.e. stream rallies claasic car etc.

As for not drilling holes i disagree, keeping more than one in an ammo box will, if one goes have others follow. Venting gas undrr pressure i think is better than a bursting metal box. Thats just my opinion i feel there will be others.

[Ron Gray]

If using ammo boxes remove the lid seal, that way they can vent without the need for additional holes.

[Chris Walby]

Only experienced one adverse event with a lipo. The battery in question was a tied old 4S3300 so rather than dispose of it I installed it in a start for IC engines. Being left in the flight box, occasional use, but high current may have caused the lipo to degrade. Anyway it seemed a bit limp starting an engine so was checked and was discharged down to about 40%.

 

Put it on charge in the clubhouse and went to fly a model, then on my return to the clubhouse to a odd smell, very puffed lipo and burn mark on the worktop. Charging stopped, disconnected and lipo moved outside. Later discharged and recycled.  

[MattyB]

3 hours ago, KenC said:

Can someone tell me where they get ammo boxes from . From my distant memories all our 7.62 was in wooden boxes with  sealed metal inners that were there more to keep things out.  I guess water might be a bit like it is when dealing with phosphorus , it stops it until the air is returned. 

Ebay, or specialist shops like this….

 

https://www.militarymart.co.uk/collections/boxes-containers

[Phil Green]

Well, to my mind an ammo box is designed to contain sudden and massive pressure bursts, thats its very purpose, if you drill it or remove the seal, jets of burning gas will escape, making the box pointless 🙂   it will blow out the seal itself if it really needs to!

 

[Geoff S]

4 hours ago, KenC said:

Can someone tell me where they get ammo boxes from . From my distant memories all our 7.62 was in wooden boxes with  sealed metal inners that were there more to keep things out.  I guess water might be a bit like it is when dealing with phosphorus , it stops it until the air is returned. 

 

I got mine from Anchor Surplus in Ripley, Derbys about 5/6 years ago. It's only about 3 miles from home.  I haven't called in for some time but the stock of 'real surplus' was getting lower, probably because the military isn't disposing of things as much as they once did.  In the early 50s military surplus sellers were exciting places for a schoolboy to visit - there was lots of fascinating things to covet - like radar racks 🙂  Perhaps, as tax payers, we should be glad there's less waste - if true!

[leccyflyer]

The most frequent advice for using the ammo boxes is to remove a section of the seal in the lid, so that they could vent, in the event of a fire, whilst retaining the flame front. That's the same principle as the genuine Lipo Sack and the Bat Safe- vent but contain the flames.

[PatMc]

When I got my first 4 or 5 lipos I stored them in a redundant oblong Pyrex casserole dish. This was placed in centre of the concrete floor of the garage with a couple of plastic bags of sand covering it. Idea being that if there was a fire the heat would melt the plastic dumping the sand over the dish, hopefully containing any flames & heat - it was never tested in earnest.  

[KenC]

Brilliant stuff guys, ammo box will be sorted .......  had not  even begun to consider the idea of transporting in the car , but having read this has made me think about it and the potential issues.  I sure hope no one from the insurance market reads any of this , can you see the disclaimers and policy excesses. 

[Graham Bowers]

7 hours ago, Phil Green said:

Well, to my mind an ammo box is designed to contain sudden and massive pressure bursts, thats its very purpose, if you drill it or remove the seal, jets of burning gas will escape, making the box pointless 🙂   it will blow out the seal itself if it really needs to!

 

I can see how that thought may have occurred, however have a different view.

 

I'd have thought the intended purpose of the ammo box is to ensure ammo is available at the point of use in good condition, so the sealing arrangement is to keep contaminants out. So it acts to keep what's outside getting in, not to act as a pressure vessel. Any pressure vessel I've ever seen is tubular or spherical and blow-off capability is proven by specific test.

 

We're using it inside-out in an improvised fashion to hopefully keep what's inside from getting out. But as it's not designed as a pressure vessel, gases must be allowed to escape. And hopefully not flames 😉

 

I think it's important to reach consensus here so readers are guided to make good choices.

 

Ideally we could read the NATO spec for an ammo box, but I've not been able to find it - anybody? The Wiki and other sources talk about the protection of the contents.

 

PS If nothing else, this thread has motivated me to improve my LiPo storage methods!

 

PPS Found this , requirements are in section 4. I have "previous" in standards and regulations, albeit in a different field, however am drawn to look for standards as a safe source of information.

 

https://data.unsaferguard.org/iatg/en/IATG-06.40-Packaging-marking-IATG-V.3.pdf

Edited July 2, 2023 by Graham Bowers

[leccyflyer]

7 hours ago, KenC said:

Brilliant stuff guys, ammo box will be sorted .......  had not  even begun to consider the idea of transporting in the car , but having read this has made me think about it and the potential issues.  I sure hope no one from the insurance market reads any of this , can you see the disclaimers and policy excesses. 

You would hope that transport in the car would be a lowish risk activity - the batteries are not being actively charged. Historically I used the genuine Lipo Sacks from the USA for charging and storage, but as my collection of lipos grew and I bought more of them, they needed to be better organised. So, for storage and transport I use three of the Zeee Power compartmentalised lipo storage bags, organised by size -2s-3s, 3s-4s and 5s-6s packs in separate bags. I charge in a pair of Bat Safes in the workshop and I take my largest, newest Lipo Sacks to the field, in the off chance that I might want to charge a pack at the field or in case I need to bring a damaged pack home to be safely disposed of. The original Lipo Sacks are the only ones that I would trust for charging in - have seen too many videos of the knock-offs just burning through or catching fire themselves.

Edited July 2, 2023 by leccyflyer

[leccyflyer]

Oh and batteries that are not in regular use are stored long term at storage voltage in a pair of Sentry Fire Safes, which I used before Mark Wood invented the Lipo Sack.

[J D 8]

In most of my time as a Coastguard we carried signal and illumination flares in ammo box's.

 A 50cal box for moving a few about and a heavy steel large caliber box for rest.

These box's are designed to keep contents dry but should a fire start inside the seal would melt and the box vent.

  Towards the end of my service we were issued with some light weight steel box's that had thousands of small holes all over and just a cardboard liner.

We all laughed and said you have got to be kidding! 

A practical demo was set up and it was amazing how well it controlled the fire of several flares burning inside with flames coming from the many holes shooting out only a couple of inches. 

 I guess if this happened in the back of a rescue truck the whole lot would still go up but give more time for crew to escape.

[David perry 1]

Me.  Lipo , a small one about 1300mah, on charge in sons bedroom caught fire.  After the fire brigade had done their best the clean up started.  Whole house ruined.  Windows gone, ceiling burnt, every piece of furniture changed.  My sons room and all.his stuff turned to ash.

 

We were lucky it happened by day or we'd have all been dead.  

 

We never ever charge lipos in the house now and we store them in tins in a second hand fridge in a shed outside.  Fire amd insurance investigators traced the cause to the lipo not the charger.   

 

The same son also had his employers workshop burn down during lipo charging...big lipos though, commercial but still the same chemistry and chargers as we use.  He wasnt nearby nor had he set the things up so no guilt!!  They lost a whole workshop so he instigated the same protocols for charging and storage after that.

 

I must say it is lipos that are driving me back to glow.

 

 

 

 

Edited July 2, 2023 by David perry 1

[GrumpyGnome]

To add some perspective, I've had 2 LiPo fires, in 9000 plus cycles (charge and fly).  Both my fault.

[Shaun Walsh]

15 hours ago, KenC said:

Can someone tell me where they get ammo boxes from . From my distant memories all our 7.62 was in wooden boxes with  sealed metal inners that were there more to keep things out.  I guess water might be a bit like it is when dealing with phosphorus , it stops it until the air is returned. 

Ebay,  50 cal ammo boxes

[Martin Harris - Moderator]

1 hour ago, J D 8 said:

 

  Towards the end of my service we were issued with some light weight steel box's that had thousands of small holes all over and just a cardboard liner.

We all laughed and said you have got to be kidding! 

A practical demo was set up and it was amazing how well it controlled the fire of several flares burning inside with flames coming from the many holes shooting out only a couple of inches. 

 I guess if this happened in the back of a rescue truck the whole lot would still go up but give more time for crew to escape.

Working on the principle of the Davy screen? Obviously not as effective as a fine mesh but useful by the sound of it. 
 

I’m not at all sure that suggestions of a sealed container in some posts are the way to go - they sound too much like a potential bomb!   A fire resistant container incorporating a fine mesh protected vent seems the best hope to be able to either contain or limit the effects of a small LiPo fire. 
 

Has anyone seen or have knowledge of such a device?

[MattyB]

The Bat Safe is the bespoke commercial solution, comes in a number of sizes now too. It is a vented solution, as you say sealing the container is not a good idea.

https://www.bat-safe.com