Australia's Biggest Tesla Battery Storage System at Moorabool is on FIRE

[EEVblog]

Australia's Biggest Tesla Battery Storage System at Moorabool is on FIRE! 
The 450MWh plant wasn't operational yet, it was still being tested.
https://www.abc.net.au/news/2021-07-30/tesla-battery-fire-moorabool-geelong/100337488
https://reneweconomy.com.au/tesla-megapack-container-on-fire-at-site-of-australias-biggest-battery/

[Ian.M]

Hmm.  You'd have thought that they'd have spaced the containers out a bit more to reduce the risk of fire spreading.   Its a green field site so the cost of say 50% more land would probably be a small part of the total budget . . .

It seems Tesla Megapacks don't come with built-in fire suppression!

Its already breaking news on select tech sites worldwide e.g. https://www.theregister.com/2021/07/30/tesla_battery_on_fire/

Edit: Tesla Megapack (summary) datasheet: https://impulsora.com/wp-content/uploads/2020/09/Ficha-Tecnica-Mega-Pack.pdf

[fourtytwo42]

I wonder how they are going to deal with all the toxic waste from that one, quietly bury it on the adjacent farmland ?

[Gyro]

"If we try and cool them down it just prolongs the process," the CFA's Assistant Chief Fire Officer Ian Beswicke said.

"But we could be here anywhere from 8 to 24 hours while we wait for it to burn down."

I guess the 'don't use water unless you have lots of water' electric car fire strategy just breaks down when you have a 13 tonne battery to contend with!

I'm a bit surprised they're not trying to cool down adjacent cabinets though. I'd expect them to suffer some thermal damage too, time will tell I guess.

[Berni]

Whops that must have been pretty expensive.

Tho i don't see why they wouldn't cover the other batteries with water. Sure it doesn't sounds like a good idea to put out the fire on this battery, its probably just gonna keep burning and its all toxic scrap now anyway. But giving the surrounding batteries a light shower of water sounds like it could go a long way in making sure they are still fine. For example the white front panels on the next battery across the row already turned black so they must be getting rather toasty. I'm sure a bit of water would go a long way for bringing the temperature of those panels down. The batteries are outside so they must survive rain anyway.

Perhaps it was more of a safety concern that none of the firefighters wanted wet mud around the burning battery becoming a shocking hazard. Don't think that would ever actually happen but firefighters are trained not to fuck with giant lithium batteries... for a good reason.

[Kleinstein]

The video footage shows some water spraying going on, though at a low level.

Tesla should have enough experiance with burned batteries, so they know how to handel the disposal of the 2 brunt containers.

[sandalcandal]

Reposting from the video thread

The suggestion of full on building brick walls between packs seems a bit excessive to me. From the photos shown the fire is only present in one bank. We'll see tomorrow morning if it spread.

The thing with many small cells being more likely to fail is intuitive but incorrect. The total capacity is of course dependent on electrode mass/area. If that capacity is achieved using many small units or fewer large units, the electrode area and chance of random manufacturing faults in the jelly roll is ~equal. By having the capacity split into small units however, failures can be better isolated and rejected in the manufacturing QC and also implementation isolating failures to single smaller cells.

Also as far as a single cell fault setting off a whole pack. IEC 62619 and UL 1973 as well as other standards for battery safety which is could fall under have "propagation testing" aka "Single Cell Failure Tolerance" if one cell blows up then the rest of the pack needs to remain safe. Reason being if there does happen to be a cell with a manufacturing fault or other random fault sneak in, it can't set the whole pack off.

From the above two you can hopefully see how small cell designs are generally considered safer.

As for what happened here, the Tesla battery pack designs are liquid cooled which should make them incredible tolerant to fire, as long as coolant is present (not even pumped, just sitting in and filling the coolant lines). Given this occurred during construction, my guess is that during commissioning there was some fault with coolant not being in the system whether that be insufficient or not at all filling the coolant or a coolant leak then during a commissioning load testing the pack with faulty coolant fill could have overheated and caught fire. The propagation testing only guard against limited individual cell failure, not a whole pack overheating.

Regardless, something went very wrong with the system/installation process.

Edit: From Ian M's datasheet


Edit2: https://www.greenburghny.com/DocumentCenter/View/7245/PB-20-18-Eagle-Energy---Tesla-Safety-Data-Sheet
Info on fire safety design. "All Tesla products undergo rigorous testing to standards such as UL 1973 and IEC 62619 that ensure the battery modules are resistant to single cell thermal runaway propagation."

[sandalcandal]

I wonder how they are going to deal with all the toxic waste from that one, quietly bury it on the adjacent farmland ?

It's a lithium ion based system not a NiCd or lead acid. The most toxic substance is the electrolyte which will be well burned off. The hazard in lithium ion battery disposal is batteries starting fires.
https://en.wikipedia.org/wiki/Environmental_impacts_of_lithium-ion_batteries

Edit: Also not sure what that "toxic smoke warning issued by authorities" is that's plastered on a few news sites. If it actually happened then it was taken down quick. Lithium ion battery fires just produce "normal" smoke. Official source: "There is currently no threat to the community though residents and motorists will notice smoke in the area. An Advice message has been issued." - https://www.frv.vic.gov.au/large-battery-fire-moorabool

[EEVblog]

Hmm.  You'd have thought that they'd have spaced the containers out a bit more to reduce the risk of fire spreading.

They are letting it burn itself out overnight, so will be interesting to see how many banks were hit. Looks like at least two, maybe 3.
This is will actually provide valuable data on fire spread in these types of systems.
Maybe they already have data on this and it's a basic cost/benefit trade-off?

[EEVblog]

Edit2: https://www.greenburghny.com/DocumentCenter/View/7245/PB-20-18-Eagle-Energy---Tesla-Safety-Data-Sheet
Info on fire safety design. "All Tesla products undergo rigorous testing to standards such as UL 1973 and IEC 62619 that ensure the battery modules are resistant to single cell thermal runaway propagation."

"Resistant" is not the same as guaranteed never to happen ever.
Standards and certification to them are not perfect.
It's all good to boast about that track record, until Murphy bites you on the arse and the incredibly unlikely thing happens.

I'm not saying it's a cell, but I wouldn't rule it out. It is afterall one of the primary, if not the primary cause of possible fire in such systems, that's why the standards exist in the first place to try and prevent it happening.

[EEVblog]

An early report in the comments is that this was its first operational testing charge, and had only been charging for a matter of hours before the fire, so 

[EEVblog]

I wonder how they are going to deal with all the toxic waste from that one, quietly bury it on the adjacent farmland ?

It's a lithium ion based system not a NiCd or lead acid. The most toxic substance is the electrolyte which will be well burned off. The hazard in lithium ion battery disposal is batteries starting fires.
https://en.wikipedia.org/wiki/Environmental_impacts_of_lithium-ion_batteries

Edit: Also not sure what that "toxic smoke warning issued by authorities" is that's plastered on a few news sites. If it actually happened then it was taken down quick. Lithium ion battery fires just produce "normal" smoke. Official source: "There is currently no threat to the community though residents and motorists will notice smoke in the area. An Advice message has been issued." - https://www.frv.vic.gov.au/large-battery-fire-moorabool

Sounds pretty toxic to me:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5577247/#:~:text=Lithium%2Dion%20battery%20fires%20generate,amounts%20of%20gas%20and%20smoke.&text=Fluoride%20gas%20emission%20can%20pose,large%20Li%2Dion%20battery%20packs.

How far that spreads, though, no idea.
I guess that's why they are taking it seriously

"A FRV HAZMAT appliance is on scene conducting atmospheric monitoring with a Scientific Officer in support. FRV’s specialist RPAS (drones) unit has also been deployed.

[EEVblog]

As for what happened here, the Tesla battery pack designs are liquid cooled which should make them incredible tolerant to fire, as long as coolant is present (not even pumped, just sitting in and filling the coolant lines). Given this occurred during construction, my guess is that during commissioning there was some fault with coolant not being in the system whether that be insufficient or not at all filling the coolant or a coolant leak then during a commissioning load testing the pack with faulty coolant fill could have overheated and caught fire. The propagation testing only guard against limited individual cell failure, not a whole pack overheating.

My reply on Youtube:

I would have presumed that the system would have a safety charging/discharge cutoff for a pack and/or cabinet in the event of a lack of coolant or coolant system failure, as the odds of something going wrong with a coolant pumping system would be orders of magntiude higher than cell failure. That would be bread-and-butter safety stuff in the design of such a system. So I'd be surprised if it's that.
What has caused the various Tesla battery car fires? There must be a lot of data on that by now?
Yes, will be very interesting to find out the actual cause.

[fourtytwo42]

Yes, will be very interesting to find out the actual cause.

I suspect unfortunately many well paid lawyers will ensure that we don't 

[sandalcandal]

Thanks for taking the time to read my responses and pinning my YouTube comment.

They are letting it burn itself out overnight, so will be interesting to see how many banks were hit. Looks like at least two, maybe 3.
This is will actually provide valuable data on fire spread in these types of systems.
Maybe they already have data on this and it's a basic cost/benefit trade-off?

IMO it should be either "safe" or a no go. The only cost/benefit trade-off is pay for it to be safe or not at all.

"Resistant" is not the same as guaranteed never to happen ever.
Standards and certification to them are not perfect.
It's all good to boast about that track record, until Murphy bites you on the arse and the incredibly unlikely thing happens.

I'm not saying it's a cell, but I wouldn't rule it out. It is afterall one of the primary, if not the primary cause of possible fire in such systems, that's why the standards exist in the first place to try and prevent it happening.

From my knowledge designing and testing for failure propagation, the main thing that can cause a compliant design to go non-compliant is elevated ambient temperature. If a whole pack is sitting toasty up at >90°C and one goes off then they're all going off. Given it's winter here right now I don't think elevated environmental ambient temperatures are the cause (16.5°C top in Moorabol today). Multiple cells being in close proximity and on the edge of failure such that a failure cluster with sufficient energy to set off the whole pack occurs seems also seems statistically pretty unlikely to me.

Even with cell failures, in liquid cooled systems it is extremely difficult to initiate any significant thermal runaway to begin with because even without coolant being pumped, once temperature hits 100°C the water based coolant boils off and hard limits the temperature rise. It generally (depending on construction and exact chemistry) takes temperatures around 120°C in a short amount of time to get cells to do something violent instead of safely venting. Having a sustained fault sufficient to deplete (boil off) coolant to the point where still volatile cells can get hot enough start significant and self-propagating fires seems also unlikely. If the coolant system was intact and filled I strongly believe there would be no fire, particularly of this scale. Perhaps some venting of a few overheated cells but that's it. Perhaps a really sustained failure event where safety monitoring systems failed to pick up a deviation and shut things down??

I would have presumed that the system would have a safety charging/discharge cutoff for a pack and/or cabinet in the event of a lack of coolant or coolant system failure, as the odds of something going wrong with a coolant pumping system would be orders of magntiude higher than cell failure. That would be bread-and-butter safety stuff in the design of such a system. So I'd be surprised if it's that.
What has caused the various Tesla battery car fires? There must be a lot of data on that by now?
Yes, will be very interesting to find out the actual cause.

You make a fair point about cut-offs for detecting coolant system failures but other than a coolant failure I don't really see how it could have gone up in flames... In the case of fiery Tesla car and battery pack failures I've looked at in the past, that all also appear related to some breach or failure of the coolant system or were otherwise exposed to a burning ICE car long enough to boil off all the coolant. My best guess is still that something went shitty with the coolant system and it wasn't caught. [Edit: I don't think actually seen the coolant monitoring systems on the Tesla packs, I mostly look at the electrical stuff and air cooled systems]

I'll ask some colleagues what they think next week. There are some other experienced lithium ion battery system engineers on this forum too so hopefully they can check what I'm saying.

I wonder how they are going to deal with all the toxic waste from that one, quietly bury it on the adjacent farmland ?

It's a lithium ion based system not a NiCd or lead acid. The most toxic substance is the electrolyte which will be well burned off. The hazard in lithium ion battery disposal is batteries starting fires.
https://en.wikipedia.org/wiki/Environmental_impacts_of_lithium-ion_batteries

Edit: Also not sure what that "toxic smoke warning issued by authorities" is that's plastered on a few news sites. If it actually happened then it was taken down quick. Lithium ion battery fires just produce "normal" smoke. Official source: "There is currently no threat to the community though residents and motorists will notice smoke in the area. An Advice message has been issued." - https://www.frv.vic.gov.au/large-battery-fire-moorabool

Sounds pretty toxic to me:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5577247/#:~:text=Lithium%2Dion%20battery%20fires%20generate,amounts%20of%20gas%20and%20smoke.&text=Fluoride%20gas%20emission%20can%20pose,large%20Li%2Dion%20battery%20packs.

How far that spreads, though, no idea.
I guess that's why they are taking it seriously

"A FRV HAZMAT appliance is on scene conducting atmospheric monitoring with a Scientific Officer in support. FRV’s specialist RPAS (drones) unit has also been deployed.

UL 1973 includes a clause for toxic emissions. As I mentioned before, the most toxic substance is the electrolyte which is generally fluorine based so can produce some toxic gasses when burnt. The amount is pretty miniscule though, particularly for an outdoor system so that's why it's generally not a problem. It can be a problem for large batteries in a confined space as that paper (and others) point out but I'd also be equally worried about general electronics smoke in that scenario. Not saying there are zero hazards and right by the emergency services to act with caution and get their own data.

Also the rest of the fire safety section you screenshoted:

They make design efforts to help prevent spread of fire from pack-to-pack as you would hope. I think it's possible we'll see only the one bank burned tomorrow (though more will need replacing for safety).

What could be a worry though is if this event turns out relatively inconsequential people will get too complacent with large battery systems. Not every system is designed like the Tesla Megapacks to such high levels of compliance. I've seen some real dodgy stuff out there. I hope it doesn't hurt the renewable industry sector but I also hope people don't get lax either.

[sandalcandal]

Yes, will be very interesting to find out the actual cause.

I suspect unfortunately many well paid lawyers will ensure that we don't 

Australia is a small country with a small renewables industry. I'm not involved in this project but I'm hoping I can hear something from a "friend of a friend" most likely from the fire department's reports on the incident.

[Marco]

The suggestion of full on building brick walls between packs seems a bit excessive to me.

I'd expect sprinklers though.

[sandalcandal]

The suggestion of full on building brick walls between packs seems a bit excessive to me.

I'd expect sprinklers though.

They're literally filled with water (inside tubes). Under normal circumstances I don't see a sprinkler system being of much use, if a fire actually starts you aren't putting it out, just preventing it from spreading... to the other water filled battery packs.

[sandalcandal]

Just found out. The installation uses the Megapack which is a different product to the Powerpack used at Hornsdale.
https://cleantechnica.com/2020/10/05/tesla-megapack-powerpack-powerwall-battery-storage-prices/
https://en.wikipedia.org/wiki/Tesla_Megapack

Megapack:


Powerpack:

[Marco]

They're literally filled with water (inside tubes).

Running water has an infinite heat capacity, a watercooling loop does not.

[Gyro]

You'd have thought that it wasn't past human ingenuity to have an X-Y grid of rails running on the ground through the whole site. It would be an easy job then to just roll in a set of vertical fire resistant barriers around the failed unit.

Damn, I should have patented the idea!

[sandalcandal]

They're literally filled with water (inside tubes).

Running water has an infinite heat capacity, a watercooling loop does not.

From the perspective of a single cell failure, the volume of the watercooling loop is the same. As I said before, something must have gone horribly wrong with a large number of cells at once or the coolant system went. As bad as it can get, in the design I can see so far, there's not any significant benefit a sprinkler system would bring to reducing the damage experienced.

Maybe it could help a bit? Especially if you expect no one to be able to show up and attend to a major failure for a few hours?

[sandalcandal]

You'd have thought that it wasn't past human ingenuity to have an X-Y grid of rails running on the ground through the whole site. It would be an easy job then to just roll in a set of vertical fire resistant barriers around the failed unit.

Damn, I should have patented the idea!

Alright, good luck finding the people to roll the barriers into place or doing automatically with any reliably outdoors!

Probably cheaper and more reliable to just space them out more or or build stationary walls if they needed to, though the seems to be they don't think they need anything?

[Gyro]

You'd have thought that it wasn't past human ingenuity to have an X-Y grid of rails running on the ground through the whole site. It would be an easy job then to just roll in a set of vertical fire resistant barriers around the failed unit.

Damn, I should have patented the idea!

Alright, good luck finding the people to roll the barriers into place or doing automatically with any reliably outdoors!

Haha, I wasn't thinking about getting a bunch of guys with corks round their hats to just wander out and take a bunch probably 1 tonne rolling barriers for a walk.

Naturally you would use mechanical means, probably using pre-layed steel cables. The infrastructure for putting the barriers on the appropriate rails and locating them would be on the periphery of the array. You're talking probably a portable crane and a few winches.

[sandalcandal]

Naturally you would use mechanical means, probably using pre-layed steel cables. The infrastructure for putting the barriers on the appropriate rails and locating them would be on the periphery of the array. You're talking probably a portable crane and a few winches.

Dave was making it sound like the whole place was going up in flames but we've only seen a single "bank" on fire and I reckon and that's all there will be. Just one burnt out bank and another charred adjacent bank. They seemed to have it under control and the lack of further news reports or alarms being called would support that assumption. I could still be wrong  we'll see soon enough. I do hope Dave makes a follow up or edits corrections into his video somehow. Some of the stuff he was saying was pretty far off.

Edit: My main issue was with Dave telling the world this must be a single bad cell and small cells make a more dangerous system.