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Comment by Renaud | Hacker News Reader

I wish we had better fire protection against these batteries.

As we're ramping up production and large packs become ubiquitous, in cars, factories, houses, we're really ill-equipped to combat their nasty tendency to burst into flames that are basically impossible to extinguish.

These things will burn if they fall below their minimal voltage, they will burn if you over-charge them, they will burn if you overheat them, they will burn if you constrain them too much, they will burn if you stab or mechanically stress them....

No fire services in the world appear to be equipped to put out those fires. At this stage, I'm wouldn't be surprised of some large-scale catastrophe brought by a defective cell in a larger pack somewhere.

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> No fire services in the world appear to be equipped to put out those fires.

Huh? Fire services have already adapted to electric car fires - they got mobile rolling container tanks in which burning car carcasses are submerged: https://efahrer.chip.de/news/warum-die-feuerwehr-diesen-bmw-...

For battery fires in buildings, the situation is a bit different. Small scale (laptop, toys, powerbank, phone) fires can be extinguished with sand or common special metal fire fighting salts which melt and thus enclose the burning battery, depriving it of oxygen. While we're at it, it is always a good idea to keep a bucket of sand in your home - in case something battery-backed burns, empty the sand bucket over it.

Large scale aka battery pack fires are uncharted territory at the moment as these are a relatively new invention... but in general, it is imaginable that regulations will be adapted, to require putting a wall power bank in a separate room, similar to how natural-gas or diesel tanks are supposed to be installed.

> thus enclose the burning battery, depriving it of oxygen

Isn't one of the big problems with lithium battery fires that they produce their own oxygen?

From water, yes. If they're surrounded by something impermeable that isn't water, then that solves it.

> Isn't one of the big problems with lithium battery fires that they produce their own oxygen?

The problem with lithium fires is that if you douse them with water, the heat of the reaction (and/or lithium acting as a catalyst, my chemistry classes are a decade ago and my memory is hazy at best) splits the water into oxygen and hydrogen. The hydrogen is the real issue as it immediately combusts explosively.

According to testing they did on the previous generation of PowerPacks, it's extremely difficult for it to catch fire, and the damage tends to be contained within a single cell. It requires a substantial event like a high-energy puncture or external fire to actually set it alight. Very curious to see the investigation on this one.

> I wish we had better fire protection against these batteries.

Even better, let's work out chemistries that don't have the same level of risk. We already have LFP, which is an order of magnitude less likely to combust. IMO we really shouldn't be using traditional lithium ion batteries for things like grid storage or home batteries where weight isn't a prime consideration. I wouldn't want one in my house, I'd use LFP instead. Or even better, LTO, though it's not as cost effective. If I have to sleep above it...

If LFP is so good, why isn't it already used? Supply?

It is popular, but it does not have the most well-known battery company in the world standing behind it. Volume EVs in China use LFP, which has the effect of making those cells common and then available cheaply in the rest of the world. So DIYers love them, and there are lots of commercial products that rely on LFP.

Tesla doesn't have any incentive at this point to use LFP, they're selling every Powerwall they can make. The people who are buying them aren't price sensitive. The folks who are, buy LFP instead.

Elon Musk has recently stated that they are going to make a big shift to LFP batteries[1]. On the Tesla's quarterly earnings call last week, he stated that iron based batteries will likely eventually be used for almost all battery applications due to the low cost. Iron is cheap and sourced all over the globe. He said airplanes and ships will probably have to still use Nickel and/or Cobalt (but corrected himself later saying only airplanes will probably need them).

[1]https://www.torquenews.com/1/lfp-batteries-pros-and-cons-elo...

That is excellent news!

I was doing some research the other day on state-of-the-art and noticed LFP was gaining some ground on power density, getting some love from Tesla is a big win. Future looks bright.

The patent portfolio for LFP could be used for free only in China since about 2003. The patents expire everywhere next year.

We learned how to very safely handle big tanks of extremely flammable fluids with explosive volatile vapors. We also learned how to deal with a system that pipes extremely explosive flammable gas into millions of homes, and outlets with high voltage electricity everywhere. We'll learn how to handle these too.

Nothing capable of powering modern society or transport is going to be made of unicorn glitter. Stored energy is stored energy and there are always dangers with it.

I am curious if Tesla's batteries have had more fire issues or if they're just reported more because it's Tesla and that makes it click bait.

I think a bit of both. Tesla is right at the edge of the current capabilities in terms of storage density so it is kind of logical that they would be the ones to find out the hard way what the real physical limits are with respect to handling and safety, and they are also the system that is the most widely deployed. On top of that anything Tesla is automatically newsworthy.

The most practical suggestion about how to deal with the problem that I've seen pass by is to ensure a certain minimum spacing between packs to create 'fire breaks' beyond which one pack can not ignite the next one over, but this would waste rather a large amount of space and probably would not work in situations like parking lots and such.

Yeah, I believe the best handling procedures for a big tank of extremely flammable fluids with explosive volatile vapours that is sitting in a fire[0] is to run away - a long way away. Sure, put out the fire and cool down the tank too, if you can do that from a long way away.

[0] https://www.firerescue1.com/firefighter-training/articles/wh...

Even with good safety procedures and legislation, we still get the storage of flammable liquids catastrophically wrong occasionally: http://www.earthquakes.bgs.ac.uk/research/events/buncefield_...

LiIon batteries may burn occasionally, but at least for grid storage the effects are localized and tend not to be explosive.

Fire services are learning how to deal with batteries [1] and most fire departments have had to adapt to new fire hazards as society changes over time with automobiles, high-rise buildings etc. For grid storage however it doesn't seem unreasonable to require each site to have the ability to move a burning pack somewhere where it can be extinguished.

[1] https://cfpa-e.eu/container-puts-out-inextinguishable-fires-...

Moving a burning pack seems overkill and unnecessarily hazardous. Rather than moving the fire to containment, it'd be a lot safer and easier to move containment to the fire. All you'd need is a few fireproof walls stored on site which can be moved into place when needed.

I'm pretty sure the lessons learned from this incident will be incorporated into future builds (and conceivably even some retrofits to this Victoria build.)

Since the stock fire-fighting response to this is (according to the article) "Keep other battery packs close to the fire cool and let it burn itself out," (Lithium fires, eh!) I'm guessing that something like automatic (fire-triggered) cooling systems (if that's not already in place - the article made no mention of existing fire-response systems and mitigations) and possibly better access between the packs for fire-fighting machinery.

I'm pretty sure that the occasional fire is just part of the risk in building these extremely large agglomerations of Lithium cells, just as it is part of the risk in existing electrical substations. All things considered, I'm reasonably impressed that the fire remained as contained as it has.

I think we need to stop giving Tesla the benefit of doubt

> I'm reasonably impressed that the fire remained as contained as it has.

Indeed—though one must assume that this kind of catastrophic event was specifically predicted and planned for. So the fact that the fire didn't spread is really just evidence that they knew what they were doing.

Electric vehicles catch fire at a much lower rate than internal combustion engines.

It turns out what you said is also true of tubes full of gasoline.

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