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Comment by ramshanker | Hacker News Reader

I am hoping for Sodium based batteries breakthrough more than increased lithium mining. All those static grid storage don’t need weight advantages of lithium. Neither home storage.

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Iron flow batteries are already in commercial use. For example: https://essinc.com

The 'cells' cost practically nothing to manufacture and utilize a membrane already common in lithium ion battery manufacturing, and there's nothing dangerous or toxic in the battery system. It's iron (in various oxidation states), salt, and water.

It's been a while since I looked at the whitepapers (which they've since pulled) but I think the secret sauce was how they managed the electrolyte's pH level.

What is the energy density of these batteries? Last time I checked, it was infeasible to replicate something like a powerwall in even 10x the volume. Which means it is a non-starter for EV.

GP says "All those static grid storage don’t need weight advantages of lithium. Neither home storage." so it might have been in that context, thus not relevant to EV

Nickel-Zinc is probably closer to reality. Sad that there’s so little talk about NiZn batteries.

In static service even lead-acid batteries are great.

Poor efficiency and limited lifespan, ongoing maintenance costs drive the costs up. Lithium iron phosphate is cheaper unless you don't use the batteries (i.e. emergency standby).

Because the dendrite problem has not been solved, and specific weight and efficiency is lower than lithium. (descending order of problems IMO).

It has been solved in modern cell designs. A lot of this is just outdated criticism.

For stationary energy storage, you don't need li-ion batteries at all.

That's what every company says, until they're in the field for a while then start dying.

Also, nickel is worse than lithium (metal) in about every way, so lifepo4 batteries are better on every dimension than NiZn: specific capacity, environmental impact, lifespan, specific power...

These problems seem to be really solved now. They’ve already are in the field and none of those doomsday scenarios seem to be happening.

NiZn batteries are actually recyclable, where as LiFePO₄ batteries are not.

You're ignoring that they are worse on every metric but below-freezing charging than lithium batteries:

NiZn: 70 to 85Wh / kg

Lifepo4: > 180

NiZn: 1000 charge-discharge cycles

Lifepo4: 3000 cycles

NiZn: significant self-discharge

Lifepo4: negligible self-discharge

NiZn: nickel is more expensive than all the metals in lifepo4 and more environmentally damaging to extract

There's nothing good about them, even if the dendrite problem was solved (which I doubt).

Lifepo4 can be recycled just fine, provided there's actually enough of them to be recycled, which won't be for a long time since they last so long.

NiZn almost certainly cheaper than LiFePO₄, at least once they get to scale. Problems like self-discharge or cycle-life likely vary depending on cell design. I'm sure you can design a cell that has less of these problems. It is also much easier to recycle than LiFePO₄ batteries, which is a big advantage. LiFePO₄ are basically never recycled in practice.

Should be noted that no one is suggest that NiZn is the end-all be-all battery chemistry. It is just a neat idea that is worth investing in, and will work in a lot of circumstances.

Nickel is $12/lb, lithium $31/lb.

Nickel atomic weight is 59, lithium is 7. $12 * 59/7 == $101

There's one electron per nickel atom and one electron per lithium atom. Nickel is 3x more expensive than lithium on that basis alone. The only useful place I see for NiZn is drop-in replacement for alkaline cells, not mass storage. Nickel is the one of the most expensive part of lithium batteries: https://www.cnbc.com/2022/03/08/nickel-price-surge-could-thr...

I'm not sure where you get the idea that it is cheaper.

> LiFePO₄ are basically never recycled in practice.

Because they haven't reached end-of-life yet. No one is going to recycle perfectly good batteries.

Note that the Tesla Powerwall is already quite heavy: 97 kg (250 lb). A sodium based battery will double that, which would make the logistics of transport and installation harder. So weight is not totally irrelevant for home storage.

Expect groups with lithium claims to interfere with cheaper competitive elements.

Every single pumpjack well in Texas is pulling up brine water extremely rich with lithium that could be cheaply extracted with evap pools. It just hasn’t been profitable until now. Lithium typically isn’t mined like gold, silver or diamonds, with a handful of exceptions.

Oh, OK, so expect the oil companies to interfere with alternatives then.

Ideally, you'd buy these wells from O&G companies at distressed prices using ESG funding and repurpose them for lithium production.

A quick google search suggests that sodium is 1000x more abundant than lithium. Will distressed prices be 1000x lower?

You actually don't even need to buy the well. Currently they pay to haul the brine water away and reinject it into a disposal well.

I think that it's going to be hard to interfere that way, they'll be too busy making money hand over fist from lithium.

The grid storage market, which sodium would serve, tends to be far more price sensitive since the storage is not attached to a massive amount of other tech that is sold primarily based on marketing and emotion, which is what sells cars. Grid storage is pure industrial economics.

I bet lithium miners and lithium battery manufacturers will be happy to hand over the grid storage market for the next decade, as vehicle battery demand will keep far ahead of vehicle battery supply.

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