Lithium Battery Fire?

[donradcliffe]

Originally Posted by HeywoodJ

Tesla makes an announcement about the switch of "industrial ESS systems" (Megapack, Megapack 2, Megapack 2 XL) to LFP about once a year during some investment call. They are, however, very, very cagey about what is actually in any specific Megapack.

As the owner/operator of a couple of dozen of the things, with more on the way, I can tell you that all they will give us is a list of 5 different Li-Ion chemistries (NCA, NMC, LFP, NMO, LiCoO2) that "may be included" in the Megapack "or a mixture of these compounds."

Unless you are intimately involved in a specific project it is nearly impossible to know what chemistry(ies) of Li-Ion are in a specific Megapack (or any other Tesla ESS for that matter).

The charging/discharging voltage points are different for each chemistry, and there is no effing way I would spend multimillions on Tesla Megapacks without knowing exactly what chemistry I had.

[HeywoodJ]

Originally Posted by donradcliffe

The charging/discharging voltage points are different for each chemistry, and there is no effing way I would spend multimillions on Tesla Megapacks without knowing exactly what chemistry I had.

Then you don't buy Tesla

That's why most of our fleet is BYD, Lishen, CATL or a few others. With Tesla everything is very opaque. We cannot directly monitor the fire suppression systems, or the cell voltages, or any other number of primary safety or operating parameters. Tesla regularly installs firmware updates and software changes without telling us. They regularly see conditions in the Megapack that we simply can't monitor and dispatch a technician - all without telling us. They're basic response, when we ask for more information is "you're the customer, you don't need to know, we take care of that for you."

At the same time their monitoring it not great. We caught a problem because one thing we could monitor, maximum temperature within the pack, was higher than we liked. Turned out to be a faulted VFD for the coolant pump. That one went right by them because they had not considered monitoring it for themselves. Only clue we got was lost capability in discharge, which led to some digging. And the only reason we know root cause is because we dispatched an operator to look over the technician's shoulder at the site.

[donradcliffe]

There's something wrong with this picture. Are you buying, or renting the megapacks, or are you buying an energy storage service from Tesla? There has to be a clear definition of who is responsible for what. Utilities are risk averse due to their regulatory environment, and I would think a black box storage service approach would not be viable.

In addition, if I was the local fire brigade, I would demand to know what toxic chemicals would be released in any thermal runaway.

[Joli]

According to published test results lifepo4 isn't as susceptible to thermal runaway or propagation as other lithium chemistries.

[donradcliffe]

Another video showing that Lithium doesn't play well with salt water.

https://www.autoblog.com/2023/11/16/...ns-underwater/

[Cheechako]

While modern batteries are great for many things, sitting in the water many miles from land would not be one of them I would think. Just sayin'...

[barcoMeCasa]

Originally Posted by donradcliffe

Another video showing that Lithium doesn't play well with salt water.

https://www.autoblog.com/2023/11/16/...ns-underwater/

Pretty much irrelevant to boat batteries though, different type of batteries. Google says model X Teslas never used LiFePo4. More likely the same sort of 18650 cells which are in your laptop or cordless drill battery pack.