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

[Daddy Tanuki]

That's exactly what I thought when I read the article. Maybe a loose connection sparked or heated up, or like you said a relay triggered a spark, that then set off some other type of gas leak.

There's no way one of those battery packs blew holes through concrete. A lot of houses in Germany are built out of thick concrete / cinder block, and it would take a hell of a lot of energy to break that apart to the point of structural failure.

That basement photo looks like someone set off a pound of tannerite.

not sure, but I don't think even a pound of low power explosive like tannerite would not do that unless it was inside a pressure vessel to concentrate the blast.

the battery cases were pretty much intact, the person has a gas water heater, and it was an insurance company blaming the batteries. thats All I needed to read. until some other agency that does not have a vested interest in either direction comes up and says it was the batteries... I call BS.

IF the battery is were one of the more energy dense version of lithium that we know can and do explode and catch fire on a regular basis I would consider it, except the fact that the battery cases were in pretty good condition form the few photos that were posted.

 

[PyroRider]

The propane is only delivered at .4 psi so the pipe would have to basically snap off to leak enough.

I work for a company that does electrics, water and gas in germany and we recently had a case where a gas boiler literally exploded due to not being taken care of in 20 years.

 

[OffGridForGood]

yeah like the home-owner that thought they would "fix" their "leaking" Hot Water Tank, by removing the dripping drop pipe from the temperature & pressure relief valve, and installing a solid threaded plug!!
The problem with a fool-proof system is our under estimation of the ingenuity of complete fools - love that statement,{Credit @upnorthandpersonal}

 

[Daddy Tanuki]

yeah like the home-owner that thought they would "fix" their "leaking" Hot Water Tank, by removing the dripping drop pipe from the temperature & pressure relief valve, and installing a solid threaded plug!!
The problem with a fool-proof system is our under estimation of the ingenuity of complete fools - love that statement,{Credit @upnorthandpersonal}

damn even I am not that stupid... must have been air force...

 

[Coydon]

that is a kiln though right? to have one of those in your own home is actually pretty impressive with what they cost.

laugh folks, When the SHTF the ability to make things like jugs, plates etc, will be worth something! just gotta figure out how to power it via solar

No problem, just oversize your home system by about a factor of 100 to run that kiln. Or just do it the way that makes sense with a few sticks. Plus, you can't get the wood effect from electric...

 

[mement0]

The investigation has come to an initial conclusion. It looks likely that it one of the server rack batteries that caused the blast after all..:

Interesting fact: this is the middle battery - the ones below and above appear to be unaffected, and were still charged (these contained prismatic cells btw, while the baked battery was built out of pouch cells).

 

[upnorthandpersonal]

Why do I have the feeling they might have been different voltages, 15s and 16s mixed? Still, the BMS should have cut that one off...

 

[Hedges]

Burned, puffed, but not ruptured.
Not like the walls of the house.

Is the theory that this battery outgassed explosive mixture, rather than burning, and something ignited the gas built up in the house?

 

[upnorthandpersonal]

Is the theory that this battery outgassed explosive mixture, rather than burning, and something ignited the gas built up in the house?

I believe so.

 

[justgary]

Still, the BMS should have cut that one off...

Maybe it did just that quite some time ago, then drained the cells to the point of instability.

 

[upnorthandpersonal]

Maybe it did just that quite some time ago, then drained the cells to the point of instability.

But then the BMS would enable charging again, as the voltage drops below the high voltage reconnect.

 

[Hedges]

BMS with cells at low SoC and voltage enables its FETs, paralleling the battery with another one at high SoC and voltage?

OK to close FETs onto a current source (SCC) but not voltage source (battery.)
Disconnect due to over-current. Wash, rinse, repeat?

 

[Zwy]

The investigation has come to an initial conclusion. It looks likely that it one of the server rack batteries that caused the blast after all..:
View attachment 190729View attachment 190730
Interesting fact: this is the middle battery - the ones below and above appear to be unaffected, and were still charged (these contained prismatic cells btw, while the baked battery was built out of pouch cells).

I'm not buying that story.

That battery box is intact. The top is bulged in the first photo, the second photo shows intact sides. An explosion inside the box would have caused the box to sustain more damage.

How does the box stay intact yet blows out a concrete wall?

 

[upnorthandpersonal]

How does the box stay intact yet blows out a concrete wall?

Cells release gasses, don't explode - gas builds up in the building, and an ignition source there causes the explosion.

 

[Brucey]

The investigation has come to an initial conclusion. It looks likely that it one of the server rack batteries that caused the blast after all..:
View attachment 190729View attachment 190730
Interesting fact: this is the middle battery - the ones below and above appear to be unaffected, and were still charged (these contained prismatic cells btw, while the baked battery was built out of pouch cells).

Coincidental timing:

BYD to stop pouch type battery production amid durability concerns: report

Electric vehicle maker BYD is reportedly planning to phase out the pouch-type batteries that have been used in its best-selling hybrids.

www.teslarati.com

I think GMs ultium platform is still based on pouch cells?

What's exciting to me is talk of mini blades I e shorter ones

 

[upnorthandpersonal]

BMS with cells at low SoC and voltage enables its FETs, paralleling the battery with another one at high SoC and voltage?

OK to close FETs onto a current source (SCC) but not voltage source (battery.)
Disconnect due to over-current. Wash, rinse, repeat?

Breaker on the rack would trip.

 

[Zwy]

Cells release gasses, don't explode - gas builds up in the building, and an ignition source there causes the explosion.

The gas in the box doesn't ignite under that theory, another hard to believe scenario.

There looks to be 32 pouch cells on each half, my guess is 4P or the other alternative would be 2P with 2 strings in parallel.

 

[Hedges]

Cells release gasses, don't explode - gas builds up in the building, and an ignition source there causes the explosion.

The gas in the box doesn't ignite under that theory, another hard to believe scenario.

And concentration inside the battery being near 100%, doesn't burn or explode.

Alternative is natural gas. What is explanation for puffing?

 

[Zwy]

And concentration inside the battery being near 100%, doesn't burn or explode.

You see this inside fuel tanks on vehicles, the fuel runs thru the fuel pump armature and windings for cooling purposes. People don't realize there are sparks from the armature with gas all around it. It can't explode, there isn't any oxygen.

If the gas inside the battery is 100%, then it displaced oxygen. No ignition possible internally, even if ignition occurred outside the battery. Which you allude to below, why the puffing?

Alternative is natural gas. What is explanation for puffing?

My theory is the battery was possibly an ignition source of a natural gas leak.

The homeowner was negligent, it seems from original story he knew there was a problem before the explosion.

 

[Hedges]

Could be natural gas was inside room and battery. Over-pressure was enough to blow out walls but not to disassemble the battery box. Ignition doesn't have to come from battery, and I wouldn't expect it to unless there was a relay.

The cells got charred. Was there a subsequent fire? Were they first damaged by the explosion?

Haven't read the report to see how they arrived at initial conclusion, "The battery did it!"