Wow, basen rack.mounts batteries destroy a home in germany

[CoolWill]

And gallon on gasoline has higher energy content than 60 pounds of TNT or C4.
Takes helluva big mansion if you can't level it with 60 pounds of TNT.

Now 1 pound of TNT won't blow a house to ground but 1 pound of wheat flour will do it.

There's no reason to keep beating this horse. But I will say that is true from a strict joule capacity. And you might get such an explosion if you completely atomize the gasoline with the correct amount of oxygen and ignite it. As far as gasoline vs TNT, the detonation velocity is important. TNT detonates at about 7000 m/s vs gasoline at 1800 m/s.

But at any rate, maybe gasoline could demolish that house. Which is still more believable than the battery doing it.

 

[Groscout]

That blast had flames riding on top, so I don't believe it was a steam explosion. Gas wouldn't have been released until after the steam explosion, so no buildup.

I would think that was gas itself.

(based on reasoning, not past experience reviewing such things.)

Now as for the Mythbusters one, I think that was electric not gas, so no flames, can't use it to evaluate the house explosion.
But it was quite effective at "disresembling" the shed.

Could a secondary gas explosion/burning cause soot buildup seen in the photos? How can you tell that you had flames “riding on top”? Also has it been determined that there was cell venting? I haven’t read the thread in whole.

 

[Groscout]

Can anyone have a legitimate conversation about boiler safeties here? HVAC guys? I’m a cross trained plumber. Residential oriented. ‘Waiting for it to rain down’

 

[hwy17]

Also has it been determined that there was cell venting?

It has not. The guy reported a strong lithium smell but even then, no more info to support whether that started before or after the explosion.

 

[Partimewages]

Can anyone have a legitimate conversation about boiler safeties here? HVAC guys? I’m a cross trained plumber. Residential oriented. ‘Waiting for it to rain down’

What do you want to know?

 

[Shimmy]

Can anyone have a legitimate conversation about boiler safeties here?

I think the challenge is mixing hazards here. It is hard to believe a RCA would not be required in a case like this, but there is a lot of missing information so far.

But, the minimum re for the water heater would be combustion exhaust and potentially make-up air, along with automatic pilot light failure detection.

For an older unit though, it is possible some appropriate safety features were missing.

 

[OffGridForGood]

Wow - Wish the title of this thread would be changed and corrected.
The title assumes a cause that is not supported.
Wait for the investigation report and post when available.

 

[Hedges]

How can you tell that you had flames “riding on top”?

This other incident was blamed on a water heater:



At the moment of explosion, there is large amount of flame, as seen in this image.
I don't believe a steam tank explosion which broke gas connection would do this. The gas would take time to come out.
I believe this was a gas leak that exploded.

But, the minimum re for the water heater would be combustion exhaust and potentially make-up air, along with automatic pilot light failure detection.

All you would need is a cracked or otherwise leaking gas connection to fill the room. Pilot remains lit, or auto-ignitor activates.

 

[Surferdudemi]

1. Do LFP cells vent during non puncture failures? Yes that's what the vent is for and why we call it a vent.

2. Are the vent gases flammable? Yes, primarily comprised of hydrogen.

3. Do the vent gases self combust during a venting event? Most evidence points to no.

We don't need youtube videos to conclude that there is a possible concern with buildup of vent gases in an enclosed area with an ignition source.

Proof of all this has already been posted in the Pytes testing.

"Yes, primarily comprised of hydrogen."

No, they are not primarily comprised of hydrogen. Of the simple gases (CO, H2, CO2, CH4), which make up less than 10% of the total, about half is hydrogen. Less than 20% of the total is hycrocarbons.

Fully 80% is "Other" in this report in figures 7 and 8:

Thermal Runaway Vent Gases from High-Capacity Energy Storage LiFePO4 Lithium Iron

Lithium batteries are being utilized more widely, increasing the focus on their thermal safety, which is primarily brought on by their thermal runaway. This paper’s focus is the energy storage power station’s 50 Ah lithium iron phosphate battery. An in situ eruption study was conducted in an...

www.mdpi.com

That's not to say they are all non-flammable, but they are not hydrogen. So any analysis that relies on the total volume of gases x 50% to get the amount of hydrogen in a room is flawed.

 

[hwy17]

I was getting that from this result, maybe I'm misreading it or it omits other gases? Oh maybe it omits all the nonflammable gases.

Still, we can see from the puncture tests the gases are flammable. So filling a room with them is dangerous.

I may be a layman but the people who did this room size calculation at SGS probably are not.



The consideration seems quite simple to me: Do you think your batteries will ever vent and if they do, do you think that's ok if it happens in your battery room?

For me I definitely don't put it out of the realm of possibility that I could have a venting situation. Today I woke up and my server rack battery is erroring out at 0 SOC after I left it yesterday at 80% and 40w load. Unexpected shit happens and we are not dealing with premium cells or premium electronics.

If it vents, I really don't want it filling up my utility room with the propane water heater, or even just getting vent gases into my house anywhere. So I am quite happy that even a potentially false alarm story has brought this to my attention and motivated me to add a passive battery case to outdoors vent path.

 

[Groscout]

Sorry @Hedges I was referring to the photos of the incident in Germany, also the video example I gave was incorrect. The myth busters example was what I was thinking of at the time. My initial argument was, steam event then some smoldering.

This other incident was blamed on a water heater:

View attachment 176933

At the moment of explosion, there is large amount of flame, as seen in this image.
I don't believe a steam tank explosion which broke gas connection would do this. The gas would take time to come out.
I believe this was a gas leak that exploded.



All you would need is a cracked or otherwise leaking gas connection to fill the room. Pilot remains lit, or auto-ignitor activates.

All that said and as much as I would like to blame a super heated steam event, I really think what happened is:

1. The/a gas appliance, gas valve failed and let enough gas in causing the explosion, likely from an unknown source of ignition. Totally plausible.

2.(Maybe more likely because this is an older house) During retrofitting of later equipment an old gas line/fittings/equipment was disturbed or damaged and leaked causing the explosion which was delayed due to the right atmospheric conditions being required for buildup. (I have personally found leaks on existing gas piping before and after gentle retrofitting. Which is why I spray listed test liquid on every joint from meter to the fixture and beyond after retrofitting. I have seen trades people yank/get aggressive on existing gas piping and legally not re test.)

Finally, if you don’t get “lithium” smell from “30kWh LFP storage” after an explosion like that (venting or not) I don’t believe you were there.

 

[Martijn]

Given the number of panels, is there any reason to think this isn't an electric boiler instead?

 

[Groscout]

Given the number of panels, is there any reason to think this isn't an electric boiler instead?

If it is this may be a consideration: https://products.geappliances.com/a...as can be produced,GAS IS EXTREMELY FLAMMABLE!!

Yes electric water heating elements do produce hydrogen..

 

[Martijn]

If it is this may be a consideration: https://products.geappliances.com/appliance/gea-support-search-content?contentId=39712#:~:text=Hydrogen gas can be produced,GAS IS EXTREMELY FLAMMABLE!!

Yes electric water heating elements do produce hydrogen..

Interesting, but this also means that the gas is inside the pipes, I'll take it he didn't open up any taps in that basement and light a flame.

 

[Groscout]

n

Interesting, but this also means that the gas is inside the pipes, I'll take it he didn't open up any taps in that basement and light a flame.

There wouldn’t need an open faucet if your electric boiler had one of these:

 

[Daddy Tanuki]

Not a good idea. But I see your approach. It’s foolish.

sorry I should have probably been a bit more specific, here is a photo that shows the conex box, as it is under a roof and has over 5' of clearance at the low end, and 15' of clearance at the high end the conex box does not get hot in the summer as a bare conex does. as such the fuel is safe.

 

[Bluedog225]

Cool place. I’d suggest you look into storing flammable liquid and explosive gas in a conex. It’s not a matter of heat. While rare, they have exploded and, from memory, killed emergency personnel. It doesn’t take much to serve as an ignition source for gasoline vapor.

All the best.

 

[hwy17]

@Bluedog225 Thanks for the PSA (to me and others). I am actually gonna stop storing my gas cans in my conex now. I'm gonna convert a well ventilated and unused chicken coop into a fuel and generator storage shed.

 

[Martijn]

There wouldn’t need an open faucet if your electric boiler had one of these:View attachment 177663

Still makes me wonder what could have been the ignition source then. Does the MP2 produce an open spark somewhere?

 

[Groscout]

Still makes me wonder what could have been the ignition source then. Does the MP2 produce an open spark somewhere?

Me too, I was going with unknown source of ignition like an electrical device that failed and caused a spark/heat. Who will ever know with the house being demolished without inspection.