LIPO pouch - best available

[Frecklychimp]

Real sorry to hear of a fellow racers injuries and wish him a speedy recovery, i'm sure he was doing his best in panic to save others and kit around him as a lot of us would in that split second by removing the blaze.

How many clubs have sand buckets available or even extinguishers? especially indoor ones based in school halls and gyms etc?

It's a rare problem, seen one flare up in a car in last 4 years (Durango 4WD rear driveshaft pin puncturing case) but still a nasty potential so we all need to think a bit smarter and take care, especially when we all cram indoors pitting in bunches at busy winter meetings.

Just ordered a 50 Cal ammo box for home storage, should squeeze a few saddle packs in fine looking at dimensions.

Will be making up sand bags using dry sand and plastic freezer sacks or something similar to line it with under around and on top of lipos just for home storage.

Been semi retired for while but it does cross my mind having a few packs sat in separate lipo sacks in the house is not enough to prevent serious damage and expense or worse.

Can live with smoke mess and couple of hundred £'s of lipos going up and needing replacing but not with the potential worst... especially when we don't spend 24hrs a day guarding them when not in use.

Lipo sacks need homologating, controlled destruction testing, possibly using the lipo packs sent by distributors for homologation?

one school hall fire will wipe out cheap BRCA insurance for all of us!

[bodgit]

These are on ebay 25cmx18cmx9cm

http://www.ebay.co.uk/itm/Genuine-Ex...item19c6eb6409

[Conrad]

Their was a good thread on rc-tech about this a while back, alot of US racers are using ammo boxes or money tins to house their lipo during charging.

Obviously much safer than a pouch but as most clubs adhere to the BRCA guidelines stating pouches must be used that kind knocks the metal box idea on the head?

[bodgit]

Originally Posted by Conrad

Obviously much safer than a pouch but as most clubs adhere to the BRCA guidelines stating pouches must be used that kind knocks the metal box idea on the head?

I think some of the posts are thinking about safe storage in their homes as well so an ammo box would be better than a sack.

[Aire valley]

Just been and bought an ammo box ! Very strong good seal etc.... but what insulation can I use in it that won't burn...? Would like to use sponge or something to protect the batteries...?

[Frecklychimp]

Originally Posted by Conrad

but as most clubs adhere to the BRCA guidelines stating pouches must be used that kind knocks the metal box idea on the head?

Do they?

i'll open the can of worms... it might be on entry forms and championship rules and in BRCA handbook but i've never been checked for using Lipo sacks or ever seen it enforced

most racers in my experience with offroad classes leave lipos bolted in the car when charging or have the spare set charging on the shiny branded pit mat/towel whilst another set are in the car... and that is the reality of it

[bpwain]

Originally Posted by Frecklychimp

Do they?

i'll open the can of worms... it might be on entry forms and championship rules and in BRCA handbook but i've never been checked for using Lipo sacks or ever seen it enforced

most racers in my experience with offroad classes leave lipos bolted in the car when charging or have the spare set charging on the shiny branded pit mat/towel whilst another set are in the car... and that is the reality of it

I cannot comment for other sections, but I assure you that this is strictly enforced at the BRCA micro nationals

.....and so it should be!

[SlowOne]

Likewise - we strictly enforce the LiPo sack usage at BRCA 12th Nationals. I also ask people to make sure the pouches are closed. Those who were present during both our incidents are usually the ones making sure that is done - they've seen how much damage can be done to their other kit when an incident occurs!

Using sealed metal boxes there must be some vents in the box so that when the pressure builds ups the lid will not blow off - then you are back to square one. There must be some vents in the box to allow the expanding gases to escape, otherwise the lids will just come off. The vents need to be numerous and relatively large as there are a lot of gases given off.

Charging in a metal box is not the best plan. When these things do get into thermal runaway, they give off copious amounts of noxious gases. As the metal box has no access for sand to be tipped on the LiPo, the gases escape into the atmosphere. Not only do we have lithium in there, we also have the noxious fumes of the plastic box and the silicone wires. This goes on for quite a time. In an enclosed space like a sports hall it might mean having to get everyone out and then trying to clear the hall of the gases.

With the LiPo sack you can take immediate action to cut off the gases at source as quickly as possible. Once smothered, the source of any gas is stopped. The incident is well-contained and can be cleared up afterwards.

Please let's not scaremonger about clubs and insurance and events that we know nothing about. The precautions are simple and not costly. Just get three large buckets of kilne-dried sand, position them where everyone at the meeting knows their location and then dump the contents promptly on any incident that occurs. It might cost the driver a few quid in new kit, and the club a table to replace and some clearing up (sand gets everywhere!) but that's it in our experience - LiPo sacks and sand.

Linings for metal boxes - try a shop that sells wood-buring stoves. Micalite board and vemiculite bricks come in thicknesses from 25mm upwards and are usually rated above 800C. I am not sure how you cut them but will guess they are a bit like tiles - score and tap. They will be more than enough for a LiPo container. My Dad used to buy asbestos boards and cut them up for his fire safe, and he lived to be 94! Those were the days...

[Frecklychimp]

I'm glad to see some sections/clubs enforcing it... as it should be!

For indoor racing it is vital when the buildings etc we use for the hobby are just rented and big expensive halls with nice floors etc

I agree with scaremongering, but common sense and the facts are that any of these incidents could start major fires, harm people/property and if it was to be flung into public eye through media etc if a school was damaged it would be a massive blow for the hobby... clubs will soon find problems sourcing venues willing to allow them use or insurance willing to cover without unaffordable premiums.

It is all our responsibilities as individuals to be safe, our hobby and BRCA is run by same likeminded enthusiasts and we shouldn't wait for these incidents to take preventative measures or argue/flaunt the rules in the name of mostly small costs compared to our race kit and bravado.

I can't see a lot of racers wanting to use ammo boxes unless they have fancy paint jobs and brand logos sprayed on them to look 'cool' but as a storage solution at home outside the sport they are a good idea.

it seems to be these incidents are commonly caused by charging issues, personally chargers should be designed to do one job i/e just charge lipos and seperate chargers for Nimh's etc but that is too late to even entertain. It is user error if a charger changes settings with a reset and doesn't check before hitting the go button.

have any of these incidents been down to faulty good condition homologated lipos charged at 1c as recommended?

why are we allowing swollen lipos to be used at meetings?

why haven't we got a list of 'safe' lipo charging sacks?

why are distributors/shops allowed to sell us the sacks that are not up to the job or do not contain any fire suitably and just delaying or making the incident worse?

[xtreme-rc]

it seems to be these incidents are commonly caused by charging issues, personally chargers should be designed to do one job i/e just charge lipos and seperate chargers for Nimh's etc but that is too late to even entertain. It is user error if a charger changes settings with a reset and doesn't check before hitting the go button.

have any of these incidents been down to faulty good condition homologated lipos charged at 1c as recommended?

yes,as ed`s dad i know what went on with his fire, all we want is that racers charge there li-po`s in a sack so that if anything goes wrong you can deal with it.
for the record, the charger was a high end li-po charger, with near new cells, charged at 6 amps, with-in the 1c
all the talk about li-po sacks not doing there job is incorrect, the heat produced is very high, with-out the pouch, at best they would be looking for a new home, at worst lets not go there,
we are still trying to find out what caused this fire, if we can but lets be honest we have all charged out of the sack, in the home and at the track, why does it have to be enforced , we should all take the safety of our selves and others and not have to watch as others walk round and check.
we certainly will and if this thread does anything it will open racers eyes as to what can happen
xtreme

[Frecklychimp]

Originally Posted by xtreme-rc

it seems to be these incidents are commonly caused by charging issues, personally chargers should be designed to do one job i/e just charge lipos and seperate chargers for Nimh's etc but that is too late to even entertain. It is user error if a charger changes settings with a reset and doesn't check before hitting the go button.

have any of these incidents been down to faulty good condition homologated lipos charged at 1c as recommended?

yes,as ed`s dad i know what went on with his fire, all we want is that racers charge there li-po`s in a sack so that if anything goes wrong you can deal with it.
for the record, the charger was a high end li-po charger, with near new cells, charged at 6 amps, with-in the 1c
all the talk about li-po sacks not doing there job is incorrect, the heat produced is very high, with-out the pouch, at best they would be looking for a new home, at worst lets not go there,
we are still trying to find out what caused this fire, if we can but lets be honest we have all charged out of the sack, in the home and at the track, why does it have to be enforced , we should all take the safety of our selves and others and not have to watch as others walk round and check.
we certainly will and if this thread does anything it will open racers eyes as to what can happen
xtreme

I think the major point is that there are different brands/types of containers sold on market as safety charging holders and from what has been said some of them will lose threads or velcro seals quickly in event of a fire inside and not contain the fire as well or could cause further issues by spreading burning debris.

In my eyes what this really means is that we need testing done to separate the best containment sacks/boxes from the weaker types/models/brands and then make sure our hobby community know that buying and using sack X is more sensible/safer than buying sack Y

We can pretty much assume that all the containers will be manufactured in China and just have various brands stuck on them for the resale companies but they need testing

I'd like to think the distributors and importers etc would actually be human enough to accept this and any results from destruction testing... if a safety product is weaker then they shouldn't be selling them

[SlowOne]

Your points are interesting, Freckly, but the issue here is personal responsibility as Ed's Dad has so carefully said. There are lots of products on the market that are tested to within an inch of their lives. Everything from aircraft to the humble toaster is tested, yet things still go wrong. The issue is what are you doing to make sure that risks are mitigated or avoided, not what someone else is doing.

If you are worried about using LiPos and 'untested' products then I suggest you find another hobby. Distributors and importers state on their products exactly what they will and will not do, so none of this should come as a surprise to anyone. Never, anywhere has anyone claimed that LiPo sacks will contain the fire absolutely. As Ed's Dad says, without the sack the risks were higher.

May I point out the error of fact in your last posts? LiPo sacks do not claim to contain debris or to spread debris. They simply claim to be able to hold a LiPo during charging and that doing so reduces risks. This is true for both types in the fires we have. Our experience is that one type does it better than the other. Since no degree of containment is claimed, no degree of performance can be deduced from the manufacturer's description. Please state your evidence that these all these containers are made in China - I have not found anything to support that.

There is no evidence that these incidents were caused by charging issues or charging above 1C. The problem is that once the incident occurs, one of the first casualties is the charger and the second thing is that it is usually disconnected by someone in the false belief that this will stop the fire. Once the incident is over, the information the charger might give us is lost from one of these two causes.

(Another tip - don't waste any time disconnecting the charger. A LiPo fire is a thermal runaway caused by the burning of the lithium. When it starts a short circuit inside the battery is inevitable at which point the charger is doing nothing to help or hinder the incident. In some case that sort circuit might blow a fuse in the charger, or damage its internal circuits. Lithium reacts with oxygen, so once started the fire is self-fulfilling. Until all the lithium is consumed, or the oxygen supply cut off (hence the sand) the fire will not go out on its own.)

If you would like to set up a qualified testing regime please go ahead. Otherwise we cannot reasonably test these products since we do not have a qualified set of circumstances that they are supposed to be tested against. I am sure that distributors and manufacturers would be pleased to accept your results providing they were scientifically researched and carried out.

I appreciate what you are trying to achieve here, but your posts are not in the least helpful to those of us trying to get the right advice to racers. Assumptions are useless and most unhelpful, bad facts even worse. It is not the manufacturers, distributors, retailers or BRCAs problem, it is our problem and we as users have to deal with it ourselves as best we can.

Xtreme - like you we have no evidence that leads to the root cause of the fires we saw. Like you both were using chargers that were not at the bottom end of the market, and like you the cells were of good specification from known manufacturers/ distributors. As stated above, any help from charger settings were lost when the incidents (and not a small quantity of sand!) wrecked the chargers.

My only clue to what might be happening was unearthed during the Sony/Dell/Apple computer fires of 2006. During that investigation it was revealed that the manufacturing process cannot prevent tiny metal fragments being in the lithium/polymers. It was speculated that if these migrate when the batteries get warm, they can puncture the separators and short circuit.

I stress I have no evidence for this but it does fit with the random nature of these incidents. We are pushing things way beyond a simple domestic-usage cell. Even at 1C we are charging modern cells at 6A to 7A!

We still cannot say what causes these incidents, so we have to mitigate the risks. LiPo pouches are the best means we know at present for charging at the races. Storing in a ventilated tin at home helps with any storage concerns. Making sure your charger is on a LiPo program with the right cell count and charge rate before you start charging, as well as closing the pouch as well as possible, all reduce risk. Finally, make sure you know where the sand bucket is.

I hope Ed gets better soon and is not put off our sport. If you do find out anything more about your incident I would be grateful if you could share information.

[mark christopher]

here is pete's favourite product, watch the video. lots of smoke yes, but seems to be no flames


http://www.oople.com/forums/showthre...ht=lipo+bunker

[SlowOne]

Yup, don't want to be in a room when that goes off!! Note the vents, and imagine what might happen if your cells are in a sealed metal box...

[Frecklychimp]

because there are no fumes with a sack?!


http://www.youtube.com/watch?v=mw8jb1KmAG8

[SlowOne]

Nope, plenty of fumes with a sack. Because you cannot get to the source of the fumes and put out the fire that creates them. As Mark testified above, our LiPo fires were out way before they would have naturally gone out because we could get to them and stop them. With a metal bunker you can't get to the source. The fumes on that video go on for over 35 seconds, ours were out within ten.

In both our cases the remains of the LiPos were substantially intact. When you open the bunker all you have is 'ashes'. What we did was to stop the fumes at source as fast as possible, something you cannot do when the source is isolated in the metal box.

[mark christopher]

Originally Posted by SlowOne

Yup, don't want to be in a room when that goes off!! Note the vents, and imagine what might happen if your cells are in a sealed metal box...

but al least there is no way velcro can melt, smoke is vented up and more controlled than a bag, and you aint going to loose ur house to smoke, but fire you could easy do.

[mark christopher]

Originally Posted by SlowOne

In the second fire, the LiPo was just tucked into the pouch near the top and the Velcro was not fully closed. Again the fire melted the Velcro (not difficult, it is plastic!), the flap popped open and the fire chucked its hot debris across the pit table setting fire to a body shell. In this case the fire was directed off the flap and so at least went only in one direction.

Originally Posted by SlowOne

Nope, plenty of fumes with a sack. Because you cannot get to the source of the fumes and put out the fire that creates them. As Mark testified above, our LiPo fires were out way before they would have naturally gone out because we could get to them and stop them. With a metal bunker you can't get to the source. The fumes on that video go on for over 35 seconds, ours were out within ten.

In both our cases the remains of the LiPos were substantially intact. When you open the bunker all you have is 'ashes'. What we did was to stop the fumes at source as fast as possible, something you cannot do when the source is isolated in the metal box.

sorry pete but im going to pick up on something here
if there in a sealed bag, how did you get to the source?
your own admission says the bag was NOT sealed and flames shot out!

there is as much chance of smothering the "bunker" than a sealed correctly bag!

[dodgydiy]

as i said before, an ammo box with the charge cables routed in through a intumescant stuffing gland is way superior to a lipo sack for charging in and also for storage. i will probably get slated for saying this again by the person who called me a cock for suggesting it before but charging in a fireproof container superior to a lipo sack should be legal in brca rules. oh and without having to pay an extra £50 for a brca approved one...... ammo boxes are superb for storing, just add some hard foam cut to size and with cutouts for your cells and you wont beat it.

[Origineelreclamebord]

Originally Posted by SlowOne

Yup, don't want to be in a room when that goes off!! Note the vents, and imagine what might happen if your cells are in a sealed metal box...

If that's a concern: poke two holes in the sealed metal box and seal the holes with something that melts or burns away in contact with smoke or heat (Polystyrene/PS, Silicon Sealant, Polycaprolactone/PCL (thermoplastic that melts around 60 degrees, so it's easy to apply/seal). That way smoke can escape instead of pressure building up.

To be honest though, I think the seals of an ammo box will not hold off overpressures a burning LiPo pack might create when burning. It would need testing, and I would say to prevent any risks, it would be best to make a it possible to open the box remotely (you never know what happens when a fresh air supply enters the equation).

As for someone's question about flame-retardant insulation: When a battery goes, they'll all go - I'd say it's only to prevent electrical conductivity with the box itself. Any insulation (no matter how flammable) will not add much to the intensity of the fire I'd say