"Hot Box" - Fire - Safe Storage. (Updated)

[Funky]

Updated build at 3rd page.  < Click here. 

 

So here is my masterpiece for safe wheel storage. I mainly built it - in case no one is home and fire starts. The fire should be contained inside the "Hot Box". I don't even plan fighting the fire.. As soon as the wheel starts burning, i will open window and run to next room, closing door behind me. I may attempt going in with one/two water buckets to damp the surrounding, while holding breath. But main idea was letting the wheel burn - till there is nothing else to burn.

The box itself is: https://www.se.com/ww/en/product/NSYCRN86300P/spacial-crn-plain-door-with-mount-plate-h800xw600xd300-ip66-ik10-ral7035-/ simple electrical IP66 steel enclosure.(~1.5mm thick walls.) I insulated inside with RockWool and added some padding at side/back. At bottom i added 2.5inch(6Cm) thick concrete blocks, to protect floor from catching on fire. Door has all the vent holes (2 holes per 1 battery cell), hole size are ~0.4inches(1Cm). I have also added second metal sheet/layer in the door themselves - meaning there is air gap between layers. Holes are misaligned, first door holes are more upwards, second metal sheet/layer holes are downwards. And built better handle for opening/closing the box itself.

I coated whole inside with little bit of PVA glue - the outer layer of RockWool, so it doesn't get destroyed so easily. (It is very thin layer of glue.. Meaning it doesn't change characteristics of RockWool and how it burns.. The thin layer will simply burn off.)

Also i built rolling self, for easy wheel storage/removal. It simply rolls in/out with wheel. (The concrete blocks are screwed to the box it self, for balanced weight.)

 

It all costed ~200$  (After update ~250$)

 

Some RockWool videos vs fire. (I tested myself with "BIG" gas torch. Sadly didn't take photos/videos myself.. Doh result was the same as in videos.)

 

 

And now for the "Hot Box" itself, some photos:

 

The 2x layered doors.

 

Side/Back padding.

 

The upgraded handle.

 

The bottom blocks.

 

 

The inside.

 

The super duper rolling shelf with stand.

 

Perfect fit.

Edited January 28, 2023 by Funky

[Paul g]

That thing is a work of art! Thanks for sharing with us. It will make our houses safer. 

I still don’t understand how you’ve done the door. Do you have something between the two panels? I would use that wool in there, so gases escape, but not sparks.

 

[Funky]

12 minutes ago, Paul g said:

That thing is a work of art! Thanks for sharing with us. It will make our houses safer. 

I still don’t understand how you’ve done the door. Do you have something between the two panels? I would use that wool in there, so gases escape, but not sparks.

 

Last image you can see those 8 smaller screws, 1 each corner and 4 in middle. I have put nut between the layers. Door/nut/plate/nut.

I tried to put the rockwool between them. But hardly any air could be pushed.. The wool get's suppressed to tightly. Holes are misaligned so should work good enough. Also there are so many holes, that the air will not "blow", but simply pass true. So sparks should not get "blown" out.

Edited September 20, 2022 by Funky

[Paul g]

2 minutes ago, Funky said:

I tried to put the rockwool between them. But hardly any air could be pushed.. 

OK. That explains it. I’m still uncomfortable knowing sparks can be spewed out.

[Funky]

13 minutes ago, Paul g said:

OK. That explains it. I’m still uncomfortable knowing sparks can be spewed out.

I at least haven't seen many sparks in battery fires.. (Mostly only fire..) Sure right at the moment when battery "pops" some burning ashes/sparks may be launched out. But still the sparks will need to travel upwards to the vent holes. And then go Zig~~~Zag past both layers. Most time till they land, they already go out. Even if little spark lands on floor, it will go out in some seconds.

Edited September 20, 2022 by Funky

[Robse]

Good job

[Eucner]

1 hour ago, Funky said:

2.3 vent holes for each battery cell. It literally has 2x the size of cell diameter to vent hole. Or is the volume/pressure so much greater? (I built the box for my ks18xl wheel in mind.. For much bigger wheels it would need to be much more robust.)

~285 vent holes for 120 cells.

 Yes, hot flammable gasses will find a way out of your box. The box won't help at all when gasses in your room ignite. Just imagine a firesak from the video in your room.

[Funky]

28 minutes ago, Eucner said:

 Yes, hot flammable gasses will find a way out of your box. The box won't help at all when gasses in your room ignite. Just imagine a firesak from the video in your room.

You mean ignite in the box.. Or at holes. Why would they ignite in room? If fire is in the box? Any flammable gas that would come out of wheel would automatically catch on fire, no? (At least i taught like that.)

And yes i positioned the box taking into mind, that flames will come out flying. Other side of the box is empty 2 meter space. -Till concrete/brick wall.

It's just natural that the gas/pressure of flames will come out flying of the small box.. I already know that. My sealing will melt for sure.  

That's why i made so many holes, so there less pressure as possible, when the flames come out. -So they don't travel as far..

Edited September 26, 2022 by Funky

[Paul g]

Maybe is better to put some handles on the box so it can be quickly taken out of the house-not a good idea to have concrete slabs attached in this case. I don’t see how anything can withstand a battery fire for long after seeing this:  

 

Edited September 26, 2022 by Paul g

[Eucner]

13 minutes ago, Funky said:

You mean ignite in the box.. Or at holes. Why would they ignite in room? If fire is in the box? Any flammable gas that would come out of wheel would automatically catch on fire, no? (At least i taught like that.)

And yes i positioned the box taking into mind, that flames will come out flying. Other side of the box is empty 2 meter space. -Till concrete/brick wall.

It's just natural that the gas/pressure of flames will come out flying of the small box.. I already know that. My sealing will melt for sure.  

That's why i made so many holes, so there less pressure as possible, when the flames come out. -So they don't travel as far..

The phases of lithium ion battery fire are:

1. A bad cell starts to heat up and swell.

2. The bad cell heats up adjacent cells.

3. The electrolyte of bad cell purges out as a grey gas.

4. More cells heats up and purges gasses.

5. The gasses are ignited from hot surfaces.

Your box is fine up to the phase 4. When gasses inside your box ignite, they will carry heat or flame to ignite the gasses vented and spread into your room. In constrained space that will create a fire ball igniting everything else in the room. The NYC S20 flamethrower case and this new Firesak case happened outdoors where the heat can escape in all directions. They would have looked much worse inside of house where heat accumulates.

Here is video of a battery burning test. It is made in well ventilated testing area. Please note how much gasses escape before it ignites.

 

[Funky]

1 hour ago, Paul g said:

Maybe is better to put some handles on the box so it can be quickly taken out of the house-not a good idea to have concrete slabs attached in this case. I don’t see how anything can withstand a battery fire for long after seeing this:  

 

Those two big Wh packs simply "blow" up the bag itself.. Because all batteries ignited almost the same time. My battery is half of that. If the box can handle those to "explosions" after that it's simple fire. As in no more flames being blown out of box itself. Carrying was never the plan. As i already mentioned, if no one is home and if fire starts..

1 hour ago, Eucner said:

The phases of lithium ion battery fire are:

1. A bad cell starts to heat up and swell.

2. The bad cell heats up adjacent cells.

3. The electrolyte of bad cell purges out as a grey gas.

4. More cells heats up and purges gasses.

5. The gasses are ignited from hot surfaces.

Your box is fine up to the phase 4. When gasses inside your box ignite, they will carry heat or flame to ignite the gasses vented and spread into your room. In constrained space that will create a fire ball igniting everything else in the room. The NYC S20 flamethrower case and this new Firesak case happened outdoors where the heat can escape in all directions. They would have looked much worse inside of house where heat accumulates.

Here is video of a battery burning test. It is made in well ventilated testing area. Please note how much gasses escape before it ignites.

 

If so, then there's no point in the box and i can simply leave the wheel on good old wooden stand without any protection. Because if it starts burning - everything will simply burn.  

Doh do "fireball" that happens what? 2-5 seconds have enough heat to start burning wood, plastic? Have you tried filling a bag/balloon full of gas and setting it on fire? It doesn't start fire.. Sure if there were paper, clothes, they would maybe start burning. Also don't forget the gases/fireball will rise to sealing. No wear near floor or my bed..

I at least try something to be "safer". Could have left it sitting right next to my bed. Without second thought. 

Edited September 27, 2022 by Funky

[sbb]

2 hours ago, Funky said:

You mean ignite in the box.. Or at holes. Why would they ignite in room? If fire is in the box? Any flammable gas that would come out of wheel would automatically catch on fire, no? (At least i taught like that.)

Almost, not quite.

Most any fuel source will offgass, but not initially ignite until it gets hot enough. With your box, the gas will pool at the top of your box and fill down until it finds a vent or two.

At that point, the excess flow out, and up, probably in a somewhat laminar stream and pool along the ceiling.

When the fuel source in the box finally ignites, all the existing gas in the box will go. This may or may not chain to what's pooled outside the box, depending on turbulence, temperature, mix, and how the various gasses ladder.

If you want more detail than that, you'll need to watch Dodson's final class on smoke which I will not reiterate here. But in a nutshell, for your setup -

• expect gasses that are not hot enough to ignite to escape your box (as you intended)
• expect those not-hot-enough gasses to ignite when, or soon after, the stuff in the box ignites
• expect gasses that are hot enough to ignite, but too rich to ignite, to escape the box
• expect those to ignite once they mix with ambient air

The setup you described should get you the time you need to GTFO if things go sideways. Just pay attention to where hot things flow to, and do not breathe any of that crap. It'll probably include a wonderful mix of phosgene and cyanide.

Remember to shut every single door on your way out, to prevent any smoke damage to the rest of the house. Shut windows as well, if you can do so safely. This will very much restrict the spread of the fire, and it's the polite thing to do - you should always let the Truckies handle any venting, so that they can watch the Engine Company put the fire out.

 

[Tawpie]

3 hours ago, sbb said:

With your box, the gas will pool at the top of your box and fill down until it finds a vent or two.

There are surveillance videos out of China showing electric scooters pre-fire, and the initial cell venting gasses they put off hugged the ground. Then they flashed in a fuel-air type ignition when the pack finally ignited. Absence flame, it looked like at least some the venting byproduct was heavier than air.

Not that it matters much… just that a runaway Li Ion pack is a scary thing indeed.

 

Edited September 27, 2022 by Tawpie

[Paul g]

In my opinion the best setup would be a metal box capable of holding water, with access from above and having a water hose attached to it with an automated opening mechanism, so the wheel can be flooded, this method being recommended by firefighters.

[Funky]

3 hours ago, Paul g said:

In my opinion the best setup would be a metal box capable of holding water, with access from above and having a water hose attached to it with an automated opening mechanism, so the wheel can be flooded, this method being recommended by firefighters.

Yeah - i thought about that, same as drooping ton of sand when fire starts. Simply takes up to much space.

Simplest method would be having another box - on top of my box filled full with sand. And have some kind cloth/plastic divider in between. As fire starts it burns/melts and fills bottom box full of sand.  

Still doesn't do anything agains so said "fireball".  Worst fire is at the start of each pack igniting. When the pack catches on fire. And when second pack catches on fire. As they like to "explode" making big "fireball".

Edited September 27, 2022 by Funky

[Eucner]

3 hours ago, Paul g said:

In my opinion the best setup would be a metal box capable of holding water, with access from above and having a water hose attached to it with an automated opening mechanism, so the wheel can be flooded, this method being recommended by firefighters.

It would take several minutes (too long) to fill the box with water from regular hose. You need a sprinkler system or a prefilled water bucket near the fire box.

Edited September 27, 2022 by Eucner

[Eucner]

5 minutes ago, Funky said:

Yeah - i thought about that, same as drooping ton of sand when fire starts. Simply takes up to much space.

Simplest method would be having another box - on my box filled full with sand. And have some kind cloth/plastic divider in between. As fire starts it burns/melts and fills bottom box full of sand.  

No, it isn't. The way water works is cooling down the batteries and stopping thermal runaway. Sand would just block oxygen path. It wouldn't work because the needed oxygen for burning is already contained in the battery chemistry.

[Paul g]

5 minutes ago, Funky said:

Yeah - i thought about that, same as drooping ton of sand when fire starts. Simply takes up to much space.

Simplest method would be having another box - on my box filled full with sand. And have some kind cloth/plastic divider in between. As fire starts it burns/melts and fills bottom box full of sand.  

I had a similar idea in my head, but with a water container on top that would immediately discharge the water in the box below, flooding the wheel right away when fire starts. A good type of such container would be a toilet reservoir. It is able to discharge the water extremely quick so water would be able to absorb the extreme heat coming from the batteries and not cause major damages around the house.

[Paul g]

9 minutes ago, Eucner said:

It would take several minutes (too long) to fill the box with water from regular hose. You need a sprinkler system or a prefilled water bucket near the fire box.

Exactly.

[Rawnei]

I just wish to point out that this is a hot topic. 🔥 🥁

That is all, i can find my own way out.

[Robse]

6 minutes ago, Rawnei said:

I just wish to point out that this is a hot topic. 🔥 🥁

That is all, i can find my own way out.

Go buy yourself some wienerbrød and calm down 

[Funky]

45 minutes ago, Eucner said:

No, it isn't. The way water works is cooling down the batteries and stopping thermal runaway. Sand would just block oxygen path. It wouldn't work because the needed oxygen for burning is already contained in the battery chemistry.

Yes - eliminating thermal runaway would be number one rule for stopping the batteries from catching on fire. Igniting next cells on fire.

Yes - batteries still would thermal runaway under the sand.. But would they burn/catch on fire? Would the wheel that is under sand catch on fire?

Edited September 27, 2022 by Funky

[The Brahan Seer]

I think I am going to make a box out of fireproof materials from these guys to stop the spread...

https://www.vitcas.com/ceramic-fibre-insulation

 

[Eucner]

15 minutes ago, Funky said:

Yes - batteries still would thermal runaway under the sand.. But would they burn/catch on fire? Would the wheel that is under sand catch on fire?

Yes, it would burn even hotter under sand. Sand would prevent some heat to escape. Sand wouldn't prevent hot flammable and toxic gasses to spread into your room.

[meepmeepmayer]

Given how complicated this is and how many things may not work as expected, I think a I have figured out the ideal EUC storage:

• Build a catapult, point it at a body of water or some wide open space or a neighbor you don't like
• Add a thin flammable trigger wire above the payload bucket
• Store EUC in bucket
• ???
• Fire concerns no more!