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Comment by IlikeKitties | Hacker News Reader

I'd prefer LFP Batteries anyway. Much more stable chemistry in regards. Higher Cycle Life, Higher Temperature Stability and they are significantly less likely to blow up or catch fire in an accident. Their only disadvantage is energy density.

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Sodium Ion is expected to be quite a bit better on cycle life in the end once its matured, they think it could go 20k or more cycles compared to LFPs 6k.

Assuming once daily cycling, that’s ~54 year service life. Wild.

“One day kids, this stationary storage facility will all be yours.”

I do wonder if you could get away with abusing an LFP battery in a way you wouldn't with NMC. If you don't have to worry about running it down so much then perhaps that makes up for the lower capacity.

Sodium batteries are much better for environment. Sodium is everywhere.

Lithium is common and present everywhere too.

I was under the impression that lfp didn't work in cold temperatures, which is a problem if you want to keep it in a shed so it doesn't burn your house down.

In the ESS context, unless you are buying bare cells, I don't think it's possible to buy an LFP battery without built-in heating.

Well, I have 15kwh of batteries in a shed (powering my internet connection and this computer, actually). The are mostly in a shed for convenience- I'm not too worried about a fire, personally.

You can charge them when freezing, but you can discharge them while freezing.

Discharging them causes their internal temperature to rise.

Last winter (I'm in the desert in CO at about 6k feet, with temps in the single digits at some points) my graphs say that they never failed to reach 40-something degrees and charge.

Maybe there are other issues I don't know about, but I certainly hope they work as well this winter as they did last winter.

LFP have a significantly more stable battery chemistry. Much more abuse tolerant and less likely to suffer thermal runaway. You'd get LFP cells so you won't have to store them in the shed due to fire safety. And while sodium ion batteries would be happy in a frozen shed they're supposed to be even more stable.

Anyway,sodium ion taking off explains the recurrent deep sales for LFP power stations. Which might still be overpriced if there developments hold up.

Most solar battery banks have moved on to LFP as of last year. They work to 10f if I'm not mistaken. Booting it up before the cold sets in will ensure it can run.

Most BMS support heating pads, but regardless sodium is superior in cold and will win that segment long term.

If safety is a concern, why not flow storage?

I see enough reports of Li battery related unpleasantness to be slightly concerned on this front, and for fixed location storage I'm less concerned with density and more so with maintenance and life span.

TFA talks about (favourable) temperature tolerance of Na, at least at the low end, I didn't see high end figures.

Would be great, actually making it work at scale isn't there yet as far as I know? And depending on the chemistry has other downsides.

I was mainly talking about cars.

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