well, this doesn't sound good.

what cathode material is used as an alternative to not make home battery a chemical weapon in disguise?

Maybe. But anyone who has worked with sodium is likely to be skeptical of that.

Are sodium fires less scary?

And gasoline fires and high speed collisions aren't? This is the bit of paranoia around EV deployment that I genuinely fail to understand. Personal vehicles are by far the most dangerous apparatus with which we interact, already. And we're fine with it! Have you ever, even once, called a Civic or Vespa "scary"?

But put a battery in it suddenly they need new tech before you'll be comfortable?

With a small but significant difference: it's in production already.

"There's no reason" just "make it safe and cheap in huge size".

Kind of like there's no reason we can't go to Mars for tourism. Just make it as convenient, safe, and cheap as a jet to London.

For some reason I wouldn't exactly feel safe knowing there is a huge battery under my house that may combust at any moment.

Cost is a reason. You need to dig out that dirt (which is expensive), it needs supports, your house needs support around it/through it…

Making things bulletproof and massive runs opposite of cheap

I don't think swimming pool is the best size. Why not a hole that's a few meters in diameter but SUPER deep? So long as your water table is sufficiently deep. This way you can service it, should you need to remove/replace contents. If it's under your house - good luck with that.

Why under the house? It can sit under your yard, no need to bother with so many tons of construction concrete on top of it.

that might be a evolutionary step where you just pump in electrolyte under a housing into waterproof container and every 10 years just pump it out again for fresh electrolyte

doesn't burn like LiFePo4 so no fire risks, though I am not sure what a short-circuit would do in damage/danger

why even under a structure though, just do it like a septic tank?

Historically, vehicles actually did have completely interchangable motive components. They were called horses.

It would have been difficult given the state of other technology at the time for the inventors of the internal combustion engine to have supplied it as a drop-in horse replacement for your carriage, but you could kind of imagine that working with current technology.

Regulations... in THIS economy and administration????

Largest Chinese companies will define the standards.

That's competing against LFP chemistry, so 33% penalty on a chemistry that itself has a penalty versus NMC.

My understanding about sodium though is that the performance in cold and heat is excellent. So even if you pay a penalty for weight, you can drop the thermal management, which saves quite a bit.

For grid storage, this chemistry will be a game changer. For vehicle, I think it has a ways to go before being preferred over LFP, but that's a guess.

I do wonder if there will be a convergence between sodium-ion battery architectures and cheaper, renewable-powered desalination. Could industrial seawater mining be competitive as a sodium feedstock source?

Not correct. Sodium-ion batteries were invented in the United States in the 1970s.