GM Backs Sodium Ion Batteries for U.S. Grid Storage • Hacker News Board

Re: GM Backs Sodium Ion Batteries for U.S. Grid Storage

#71

Post by lostlogin » Sun, Jul 26, 2026, 6:17 AM UTC

scarecrowbob wrote: post #53

AussieWog93 wrote: post #42

Earlier quoted context omitted.

I mean, I pay around $2,000 (AUD) per annum for electricity from the grid. If this battery plus some solar panels could get us free power for the next 20+ years, that's easily worth $15-$20k or so.

I am about 2 years in to my off-grid solar setup. The cost for the easement was looking to be about $25k, plus about 30k for the wire, transformer, et. I live in middle of nowhere so I just built out a system myself. I am about 8k into it. It's not the biggest system (6kw inverter, 4kw panels, 15kwh storage) but it's fine for one old man living a 2kM in the high desert.

Just to clarify - you were looking at 50k+ for an on grid setup and solar + battery has cost you 8k so far?

Re: GM Backs Sodium Ion Batteries for U.S. Grid Storage

#72

Post by wiml » Sun, Jul 26, 2026, 6:31 AM UTC

antisthenes wrote: post #29

TwiztidK wrote: post #4

My company operates two Jupiter Power owned LFP batteries in the MISO market. Each of them draws .5 - 2MW constantly for the HVAC system. If the cost for sodium batteries is similar to LFP, that alone would be a reason to switch.

> If the cost for sodium batteries is similar to LFP, that alone would be a reason to switch. Why would that be a reason to switch, given the LFP batteries typically have better operational parameters in everything except cold-weather charging?

My interpretation of TwiztidK's comment is that they could save the cost of that .5–2 MW power draw by switching to a battery chemistry with looser temperature requirements.

Re: GM Backs Sodium Ion Batteries for U.S. Grid Storage

#73

Post by tromp » Sun, Jul 26, 2026, 7:00 AM UTC

lebuffon wrote: post #35

xbmcuser wrote: post #32

Earlier quoted context omitted.

AT grid scale, sodium quickly closes the gap on lithium. The safety overhead, active cooling, and physical spacing needed to control lithium’s thermal runaway risk eat away most of its energy density advantage. Plus, CATL is hitting cost parity between full sodium BESS and LFP BESS systems.

The other big reason is the longevity. LFP life span gives you about 2000-5000 cycles depending on where your application can't tolerate the capacity reduction. Sodium Ion can go to 10,000 cycles (27 years) with a 70% capacity reduction at that life. This makes financing a large grid scale storage plant look way better to the bean counters because the investment continues to work and make money, after the 5 year amor…

> Sodium Ion can go to 10,000 cycles (27 years) with a 70% capacity reduction at that life.

The article claims much better:

> the company’s GS1.1 [Sodium Ion] system will store energy for 20 years, over roughly 20,000 cycles, and still retain 80 percent of its capacity. For LFP, a basic durability benchmark pegs them at 70 percent capacity after 8,000 cycles.

Re: GM Backs Sodium Ion Batteries for U.S. Grid Storage

#74

Post by ZeroGravitas » Sun, Jul 26, 2026, 7:02 AM UTC

cyberax wrote: post #6

Keep in mind, we could have had local Na-Ion battery production in the US. The company producing them needed about $5m of bridge loans, with products already sitting in warehouses awaiting the UL certification. This company got sold for scrap.

Re: GM Backs Sodium Ion Batteries for U.S. Grid Storage

#75

Post by [deleted] » Sun, Jul 26, 2026, 7:16 AM UTC

lebuffon wrote: post #35

xbmcuser wrote: post #32

Earlier quoted context omitted.

AT grid scale, sodium quickly closes the gap on lithium. The safety overhead, active cooling, and physical spacing needed to control lithium’s thermal runaway risk eat away most of its energy density advantage. Plus, CATL is hitting cost parity between full sodium BESS and LFP BESS systems.

The other big reason is the longevity. LFP life span gives you about 2000-5000 cycles depending on where your application can't tolerate the capacity reduction. Sodium Ion can go to 10,000 cycles (27 years) with a 70% capacity reduction at that life. This makes financing a large grid scale storage plant look way better to the bean counters because the investment continues to work and make money, after the 5 year amor…

[deleted]

Re: GM Backs Sodium Ion Batteries for U.S. Grid Storage

#76

Post by adrianwaj » Sun, Jul 26, 2026, 7:17 AM UTC

“You need to keep an LFP cell at 25 °C, give or take, or it will rapidly degrade” so LFPs have to be heated and cooled - not difficult to solve but it does add cost and complexity to a battery, something Sodium-Ion doesn't require.

But looking at the discharge profile of Sodium-Ion [1], then a 24v stable output would need about 48v at 100% battery charge and that means cost and complexity on the input and output sides to keep a steady voltage over the discharge cycle. LFP have a much flatter discharge curve but it's a much greater concern with Sodium Ion. Sodium Ion is also criticized for its lifetime cycle degradation.

LTO (Lithium Titanate) batteries hit the sweet spot between both chemistries and are used in electric buses, but I still like Sodium batteries for their environmental considerations.

Wouldn't it be great to somehow harvest power from the temperature swings between night and day in arid regions? Also large changes between sea level and cruising altitude.

I know black tourmaline and certain lithium compounds being pyroelectric generate power upon temperature change due to mechanical stress, which instigates piezoelectricity.

"If the goal is maximum electrical energy generated per degree shift, single-crystal PMN-PT (Lead Magnesium Niobate–Lead Titanate) is currently the top-performing synthetic material." [2]

[1] https://hackaday.com/2025/10/30/why-sodium-ion-batteries-are...

[2] https://share.gemini.google/0wylEwjLUcOL

Re: GM Backs Sodium Ion Batteries for U.S. Grid Storage

#77

Post by ryzvonusef » Sun, Jul 26, 2026, 7:39 AM UTC

from what I've heard, the problem with moving sodium from lab to manufacturing is that all the industrial processes and machinery have been setup for lithium and the factories are reluctant to invest in entire new sodium setup for not much benefit for them; lithium works perfectly well and is in fact the superior product, why switch?

Lithium prices have faced a massive crash, so there is no cost penalty for them anymore. Sodium's cost benefit isn't that significant now, and while other technical benefits exist, the question remains, is it worth it to setup an entire new factory from scratch for that marginal benefit?

Re: GM Backs Sodium Ion Batteries for U.S. Grid Storage

#78

Post by hgomersall » Sun, Jul 26, 2026, 7:54 AM UTC

I've been pondering the question of what happens if you change the design requirements to say, 20 charge/discharge cycles in total, then use it over seasonal timescales. Can you get the price so low that you can scale up enough battery storage to buffer a whole season?

Re: GM Backs Sodium Ion Batteries for U.S. Grid Storage

#79

Post by ZeroGravitas » Sun, Jul 26, 2026, 8:27 AM UTC

ryzvonusef wrote: post #77

from what I've heard, the problem with moving sodium from lab to manufacturing is that all the industrial processes and machinery have been setup for lithium and the factories are reluctant to invest in entire new sodium setup for not much benefit for them ; lithium works perfectly well and is in fact the superior product, why switch? Lithium prices have faced a massive crash, so there is no cost penalty for them any…

Sodium batteries use a relatively similar process to lithium, so I'd say overall that has sped up their adoption in manufacturing.

But the economics part is true, people looked to sodium as lithium prices went high and then enthusiasm cooled as they dropped again.

However they now seem to be passed that slump and the long term benefits seem enough for sustained investment.

It helps that the wider market is growing. You can keep your lithium battery factory and use your know how to set up a new sodium battery factory and aim to sell both to slightly different markets for the life of a factory.

Re: GM Backs Sodium Ion Batteries for U.S. Grid Storage

#80

Post by amluto » Sun, Jul 26, 2026, 8:44 AM UTC

adrianwaj wrote: post #76

“You need to keep an LFP cell at 25 °C, give or take, or it will rapidly degrade” so LFPs have to be heated and cooled - not difficult to solve but it does add cost and complexity to a battery, something Sodium-Ion doesn't require. But looking at the discharge profile of Sodium-Ion [1], then a 24v stable output would need about 48v at 100% battery charge and that means cost and complexity on the input and output side…

LFP’s flat discharge curve is actually kind of annoying: it makes it quite difficult to measure the state of charge of a cell. BMSes mostly need to track the SoC by counting coulombs, and balancing a series of cells may be challenging unless the SoC to reach the steeper part of the curve.

Meanwhile, most serious applications have power conversion circuitry, so a variable voltage may not be much of a problem.

The low-end “12V” LFP packs without real BMSes or power conversion that sort of pretend to be lead-acid batteries in RVs and such are awful designs and work pretty poorly, and their “24V” and “48V” cousins are not much better. It’s true that Na-Ion may not be an easy drop-in replacement. That being said, some people are working on Na-Ion as a lead-acid replacement for car starter batteries (and for low voltage systems in EVs), and they have a lot of potential in this application. (LFP doesn’t have adequate not temperature performance and lead-acid sucks for many reasons.)