Fire Resistant Charge Box

[BTCat]

Well, I could say "Fire Proof" but by definition, it isn't that good. I built a charge box and is relatively air tight and Could contain a lipo fire much better than those bags. Dam those bags are expensive and if the battery does catch on fire, it allows a substantial amount of flame to remain uncontained, or at least in the demo vids I've seen. I'd bet the box I build could contain and smoother a blaze.

I Velcroed my charger to the outside of it and put all my lipos inside. Took me all of 30 minutes to make and that was taking my time. The only weakness I see is that an electrical fire could follow the wires out.

I'll upload a pic in a minute

Here ya go...

[Solitaire]

What's the construction, BT?

[BTCat]

5/8 in drywall -- I forget the burn through rate. Ern probably knows. EDIT: Burn Through Rate 45 minutes

Fireplace mortar via a caulk gun. You can't see it, but all gaps are sealed

50 Cal ammo box with sealed lid.

In the event of a fire, it should contain, vent and smother. I don't think a completely air tight container is a good idea. I think they call that a bomb

[coffinsnail]

actualy if you think about it, it would not be a bomb. because the idea of air tight is no fule for the flames. it will burn out but you would have to let it set till it was cool before opening because then you would get the back draft effect. if you leave it so air can get in, it wont smother it will just burn slower. only two ways to put out a fire without a extingisher, remove the air (fuel) or smother it with to much fuel.

i would say seal it up where the wires go in, plus you have to think that box is going to get really hot if it does catch on fire, with air holes and without, the can is metal. i would suggest lining the outside of the can with some engine heat material used in cars just incase you need to move it. also i would suggest jamming the handle so its always up. might even be worth it to buy a small thermometor to stick on the outside just to see if its hot before touching the can.

i am unsure to the lipo may not need any o2 to burn since its a chemical based battery the fire might be the chemicals more then the air causing the burn. hard to say.

what would be cool is some fire foam, would be cool if you could line the lid of the box with some kind of fire foam that expands when it touches air, then you could seal it in a small plastic bag in the top, and let the fire melt the plastic to release the foam.

but yah thats a pipe dream but sure sounds cool. actually i wonder if you could make a special bag with alot of say backing soda in it to do the same thing ...

[BTCat]

I'm not sure how much of an oxidizer there is within the lipo. There is certainly a chemical reaction, if you view the sample videos of the fires. The reason I think an unsealed can works is that the opening is about .30 in by 1 in. Enough to vent, but not enough to allow sufficient oxigen to sustain the fire for more than a few minutes at best. The lipo fires seem very intense initially and then smolder. Its The chemical storage units I work around all accomplish this with what I would call blow out (or melt out) plugs. If a lipo were to burn in a sealed enviroment, even with the fire being starved of oxigen soon after, the pressure in the can would be dangerously high. That can would puff up like a toad inside of a few seconds.

Good idea on the contained foam. I have seen picks of sand bags being used, but I would think it would take quite a bit of sand. I could put a mini Argon cylinder on it. That would be doable. Not practical, but doable.

From a practical standpoint, though, simple is better to me. I would love to test this thing. I think it would put a lipo bag to shame. The biggest concern with it, or a lipo bag, is the possibility of the fire shorting out the charger. If the charger is worth 2 cents, it would shut off at the first sign of a short (if people would use their balance plugs :

Look at that -- 2:00 in the morning here. Dam pain pills aren't doing the trick tonight.

[coffinsnail]

yah know chargers are not cheap i think i would prefer it not mounted to the box, cause the box will heat up and that heat will transer to the charger. thus it could cause a internal short in the charger ruining the charger, even if the fire is contained in the box and smothered.

yah cause no matter what even a first burst from the lipo will generate enough heat to pass from the box to the outside of the charger, and i bet the wires and conductors resisters ect inside the charger are small and will not be able to handle any heat at all.

my suggestion un mount the charger and keep it a couple inchs away so it can not touch the box incase of fire.

[19000rpm]

I think the box looks like it will work great.

[akent]

I agree! That looks like a great idea and design!

Come to think of it, I think I have a couple of ammo boxes laying around somewhere. One for charged up batts and one for discharged ones?

Lithium needs oxygen to burn, but can also react with nitrogen. I would think less air is better in a container.
Kent

[brunaribeiro]

I probably will invest in a lipo bag, just have to look around. Its a
small price to pay for peace of mind, considering what could happen
should one of these batteries go.