Grid-scale batteries: They’re not just lithium

When size and weight don't matter, lots of other battery chemistries can work.

See full article...

 

[cbreak]

I'm not an expert in this area... but what about just pumping a lot of seawater up a mountain, and then slowly releasing it through a turbine generator whenever you need more electricity? There's no loss of stored energy over time like with chemical batteries.

Side benefit: if you happen to have extra energy, you can use the water pressure to push that seawater through reverse-osmosis filters and get freshwater, which is scarce in certain parts of the country, like California.

Is anyone doing something like this already?

That sounds like a bad idea, seawater is very corrosive.

 

[real mikeb_60]

Thank you for this, here in the UK and likely everywhere, there are lots of very loud voices shouting about wind not blowing or sun not shining. I wish they'd just listen to experts for once without whining. Renewables are the essential majority component of a modern energy grid and anyone arguing otherwise is a fool or paid to say so. Debate should be about the lowest cost way to get peaker-equivalent generation, not the rest.

The real point is that there is no silver bullet when you're looking at a renewables-dominated system. In the olde dayze, if you needed more power, you built another coal plant and then griped that people didn't use enough power to keep it running all day and night so you had to convince them to use more, which then resulted in the need for more power at peak times, rinse and repeat. Or use some gas turbines or diesel engines for peaking. And not worry about the stack emissions from all of that. Yes, you can replace some coal with nuke, for a price, and then have to deal with the waste for 10K+ years. It's still industrial electricity produced by burning something.

It's a harder management job to have renewables power a lot of a grid because no single or small number of technologies will do the job. An "all of the above" approach is needed. CA ISO, for all its faults, is demonstrating how some of that can be done. Look at their (near-real-time) sources displays. Yes, at certain times, renewables as a group may come close to powering the state. And solar is the Big Noise among renewables during the day. Lots of other things are in the mix, though, including recently a lot of (and growing rapidly) batteries. So far, they don't break down what kind of batteries. That's probably deeper into the weeds than makes sense under present circumstances, as long as they can store power in and drain it from them enough when needed.

As for small-scale storage tech: all my old UPS boxes in the house use small SLA. Works fine for situations where they sit at 100% almost all of the time except when a brief self-test is going on. The UPS makers want me to change the batteries annually or so; I've been going on more of a 5-year cycle. The UPS's can still run the desktop for 30-40 minutes, and the gateway/router for longer than AT&T can supply digital service during a (thankfully very rare) power outage.

Edit: forgot link

 

[numerobis]

Northvolt's isn't NaS, and the newer Chinese ones aren't either, IIRC. Na‑ion, instead. Most of the current production and research seems to be focused on Prussian blue analogues as the cathode, with carbon anodes. I don't think there is any sulphur in the electrolyte either. There was some research in China on MoS₂ anodes, though.

Oh, whoops, how’d I get that notion?

 

[DovePig]

Oh, whoops, how’d I get that notion?

Probably mixed them up? Happens to the best of us NaS batteries exist (though most were high‑temperature only I think) and were also used for grid storage and also produced in China, IIRC, so it's an easy mistake to make.

 

[jimlux]

~70% round trip efficiency in just the battery is their big drawback, until long duration storage is incentivized by regulators that's enough to keep them from being widely deployed.

70% may be perfectly fine - if you’re storing solar power, just build the solar installation a bit bigger. The incremental cost may be less than other techniques to solve the storage problem I don’t know what round trip is for pumped storage, but I think it’s in the 70-80% range.

 

[jimlux]

The trade off with flow batteries is charge/discharge rate is significantly reduced compared to cell batteries, they tend to be big, though, because they need to have 2x the volume as their electrolyte takes up, just in electrolyte tanks, mostly seasonal grid, the advantage is that they can scale up almost at cubed square and the electrolyte can be cheap.

On the other hand, if you’re adding storage to a square mile of solar panels or solar thermal in the desert, the extra space probably isn’t a big deal. And it’s not like you need exotic construction or manufacturing - people have been building large tanks for centuries.

 

[real mikeb_60]

"These batteries do not require the critical minerals that lithium-ion batteries need, which are sometimes from parts of the world that have unsafe labor practices . . . "

Unsafe labor practices, is really underselling it to the point of outright deception. We're not talking about technical Osha violations. I think the human suffering involved in making these things is a greater externality than any environmental consideration, of course YMMV.

https://www.npr.org/sections/goatsa...48/red-cobalt-congo-drc-mining-siddharth-kara

Cobalt is the main "conflict mineral" used in Li batteries, but only in certain formulations. Li-(cobalt-containing formulations) batteries have their uses, where high power and energy density are important (like in transportation). With the improvements made to LFP in China (yes, they were invented in the US, but the patents were sold to Chinese companies a long time ago), though, it makes little sense in most grid situations to use the cobalt-containing batteries. LFP uses ... lithium, iron, and phosphates, which are not usually considered "conflict minerals".

And when you hear or read about batteries requiring "rare earths" you are truly seeing FUD. Those are used in permanent magnets for electric motors (for which, also, there are alternatives), but not in batteries.

 

[jimlux]

I think the next likely step will be sodium ion batteries in standard formats like 18650 or 21700. I say this because they reuse existing industrial equipment but have less expensive inputs so the time to ROI on scaling up their manufacturing will be shorter than custom solutions. The one thing that could upset this prediction is government intervention, if a major countries government were to throw money behind mass serial production of flow batteries for grid scale use then you might be able to get steep enough on the adoption curve for it to reach practical pricing, but so long as all that is funded is research and pilot programs you're never going to reach a $/kWh that will compete with the established tech.

There are large battery plants in industrial UPS applications and they don’t use 18650 cells. The small cells are used in cars because they need the energy density, and they’re leveraging the enormous consumer market for small cells. But big batteries have been around for a long long time. Phone exchanges, industrial UPS, etc. have rooms full of racks with big batteries. And big batteries have a lot of advantages - manufacturing tolerances are looser, for instance.

 

[jimlux]

I'm not an expert in this area... but what about just pumping a lot of seawater up a mountain, and then slowly releasing it through a turbine generator whenever you need more electricity? There's no loss of stored energy over time like with chemical batteries.

Side benefit: if you happen to have extra energy, you can use the water pressure to push that seawater through reverse-osmosis filters and get freshwater, which is scarce in certain parts of the country, like California.

Is anyone doing something like this already?

Pumped storage is very common. Not with seawater, but with fresh water (because you can leverage an existing hydro installation fed by a river filling a lake).

 

[Oldmanalex]

For those who can only conceive of batteries in vehicles, sodium-sulfur was tried. Ford worked on it, and ran a small test fleet of Transit Connect predecessors with NaS batteries. Yes, a few caught fire; the sulfur was corrosive, and when it leaked it burned at the 300F+ the batteries ran at. Ford gave up on NaS and moved to fuel cells and lead-acid (much later, Li-Ion) batteries. See: https://en.wikipedia.org/wiki/Ford_Ecostar

Sodium-sulfur has been around for a very long time. Back in the '80s people were talking about them for train locomotives, as the high temperature and bulk could easily be handled in a loco, but not in most road vehicles. Also collisions are much rarer on railroads than roads, and molten sulfur, and more particularly molten sodium, are not things you want leaking out after a crash. Part of the loco size advantage was plenty of capacity for both insulating the hot cells, and armoring them against collisions.

Although I understand the cobalt human rights concerns, I am a little skeptical when these are offered as major advantages of different battery chemistries. The future may have a different set of conflict minerals, but the thermodynamics and efficiencies and discharge characteristics of the different battery chemistries are pretty much forever. So if not talking up the good technical points first, I tend to get a little suspicious. Think of the children is not an opening gambit that I expect when discussing energy storage modalities.

 

[Oldmanalex]

See: https://en.wikipedia.org/wiki/Mediterranean-Dead_Sea_Canal. That's a fairly straightforward hydroelectric scheme, not a battery, and not based on any kind of pumping. Once-through.

One could conceive of something similar between, say, the Gulf of California and the Salton Sea, but the difference in elevation is less and the collateral damage (loss of agriculture and other things - like the Coachella festival - in the region as Lake Coahuilla redevelops); and there's speculation that the southern San Andreas would come unstuck if the Lake reappeared providing water to lubricate the fault.

Pumping water up the hill then collecting power from it when it runs back down is standard pumped-hydro. It's a great setup if you have enough elevation difference over a short distance and plenty of water available. Both of those are limiting factors.

Pumping salt water into a fresh water system is a really bad idea. Period.

 

[jimlux]

My problem with "old obsolete" SLA is its high internal resistance, and how you really shouldn't run it to near 0% SoC, even for deep-cycle batteries. High internal resistance means you can't easily put a prolonged high load on it (voltage dips too quickly at lower SoC), and a reduced depth-of-discharge rate means you're actually only able to access 60-70% of the energy available in lead acid.

With LFP batteries being ridiculously cheap these days - and I would say almost on par with SLA per Wh, since you can actually use more of the energy stored - there's no good reason to stay with SLA for indoor use. (Not being able to charge below freezing point is a significant drawback for some applications, I'll concede that)

LFPs can sit at 100% for a prolonged time without degradation (it's not that your SLAs in UPSes are staying good forever either), and a good BMS with a shunt and proper calibration shouldn't have any issues figuring out pack SoC.

On a large installation, recalibrating “segments” of battery would be easy. Nothing says you have discharge all the batteries at the same time. If you had, say, 6 batteries, you discharge #1 to end, while holding #2,3,4,5,6 at full charge (or whatever). Next time you discharge #2, etc.

 

[fenris_uy]

Given that the flow batteries are listed as more expensive than li-ion. I'm guessing that the cell membrane is really expensive and has to be replaced frequently.

 

[jimlux]

The real point is that there is no silver bullet when you're looking at a renewables-dominated system. In the olde dayze, if you needed more power, you built another coal plant and then griped that people didn't use enough power to keep it running all day and night so you had to convince them to use more, which then resulted in the need for more power at peak times, rinse and repeat. Or use some gas turbines or diesel engines for peaking. And not worry about the stack emissions from all of that. Yes, you can replace some coal with nuke, for a price, and then have to deal with the waste for 10K+ years. It's still industrial electricity produced by burning something.

It's a harder management job to have renewables power a lot of a grid because no single or small number of technologies will do the job. An "all of the above" approach is needed. CA ISO, for all its faults, is demonstrating how some of that can be done. Look at their (near-real-time) sources displays. Yes, at certain times, renewables as a group may come close to powering the state. And solar is the Big Noise among renewables during the day. Lots of other things are in the mix, though, including recently a lot of (and growing rapidly) batteries. So far, they don't break down what kind of batteries. That's probably deeper into the weeds than makes sense under present circumstances, as long as they can store power in and drain it from them enough when needed.

As for small-scale storage tech: all my old UPS boxes in the house use small SLA. Works fine for situations where they sit at 100% almost all of the time except when a brief self-test is going on. The UPS makers want me to change the batteries annually or so; I've been going on more of a 5-year cycle. The UPS's can still run the desktop for 30-40 minutes, and the gateway/router for longer than AT&T can supply digital service during a (thankfully very rare) power outage.

Edit: forgot link

Hawaii is also doing a lot with storage and trying to integrate countless individual small installations. The big deal is that without a lot of “spinning mass” keeping the grid stable is tougher, particularly when you have distributed generation and storage (e.g. houses with batteries) that isn’t centrally managed.

There’s a whole lot of research on Grid Forming Inverters that can supply reactive power and be dispatched.

 

[TreeCatKnight]

This depends on the storage use case. For very long term storage with few charge/discharge cycles, the "cost of inefficiency" becomes unimportant compared to the capex of energy storage capacity. On that, hydrogen can be far superior to batteries.

There was an illuminating discussion of this recently in another thread.

https://meincmagazine.com/civis/threa...rst-half-of-2024.1502569/page-7#post-43119624

I'd very much like to know how long term storage of hydrogen works.

Because it doesn't.

 

[fenris_uy]

I'm not an expert in this area... but what about just pumping a lot of seawater up a mountain, and then slowly releasing it through a turbine generator whenever you need more electricity? There's no loss of stored energy over time like with chemical batteries.

Side benefit: if you happen to have extra energy, you can use the water pressure to push that seawater through reverse-osmosis filters and get freshwater, which is scarce in certain parts of the country, like California.

Is anyone doing something like this already?

Evaporation exists, so you have losses if you don't have a non pumped source of water.

There are already some hydro storage facilities. The one that I can name is the one in Niagara falls. Also every damn is a passive form of hydro storage if your damn isn't near it's peak storage level. Generate less power when the sun it's up store water.

 

[leonwid]

So I have the same musing a lot of you do - we used about 16.5MW of power in the last year at my home, and so I would have loved to see more details about how many MWH/etc. these things could provide. As somebody else mentioned above:

Yes, you can currently get generators that run on LNG/etc. around here for the occasional power outage, but imagine if every home had a "power bank" that could power their house for upto 6-12 months during a power outage. And even in communities with smaller lots, a "small" one of these providing upto a 1-3 month supply? Especially with a wide solar initiative, it seems like we could then really focus on optimizing our power grid and lowering costs. (Not that the privatized monopolistic power companies in the US would allow it, but....)


All that aside, it's cool to watch how the power storage industry is moving forward esp. with advances in car and solar technology. Slow but steady progress!

12 months of energy in a form factor small enough to be attached to a house. I have the feeling that that involves a fairly high energy density. I wonder what technology can handle that density safely in an urban setting.

 

[numerobis]

"These batteries do not require the critical minerals that lithium-ion batteries need, which are sometimes from parts of the world that have unsafe labor practices . . . "

Unsafe labor practices, is really underselling it to the point of outright deception. We're not talking about technical Osha violations. I think the human suffering involved in making these things is a greater externality than any environmental consideration, of course YMMV.

https://www.npr.org/sections/goatsa...48/red-cobalt-congo-drc-mining-siddharth-kara

The lithium ion batteries these ideas are competing with also don’t use cobalt.

 

[numerobis]

Pumping salt water into a fresh water system is a really bad idea. Period.

The Dead Sea is famously not fresh water.

 

[SparkE]

Thank you for this. We don't usually hear much about the non-Lithium Ion battery tech currently in use.

I wonder how some of these technologies compare with the giant lead acid batteries that local telcos used so that landline phones remained working even during a power outage. For those of you who may remember, 50 years ago when power outages occurred, landline phones always remained working. They had giant vats of acid, each one a cell in an array to achieve the desired voltage. As I remember, those cells lasted for decades and I don’t remember them having a lot of drawbacks other than size. For all I know, maybe these batteries are still in use.

I guess my main point and a point brought up by others is that when space isn’t a problem, you don’t necessarily have do use a lot of expensive, exotic materials and engineering to store grid power for use when renewable sources aren’t at peak production.

 

[fenris_uy]

I wonder how some of these technologies compare with the giant lead acid batteries that local telcos used so that landline phones remained working even during a power outage. For those of you who may remember, 50 years ago when power outages occurred, landline phones always remained working. They had giant vats of acid, each one a cell in an array to achieve the desired voltage. As I remember, those cells lasted for decades and I don’t remember them having a lot of drawbacks other than size. For all I know, maybe these batteries are still in use.

I guess my main point and a point brought up by others is that when space isn’t a problem, you don’t necessarily have do use a lot of expensive, exotic materials and engineering to store grid power for use when renewable sources aren’t at peak production.

Isn't the electrolyte in lead acid batteries pretty toxic?

 

[numerobis]

Isn't the electrolyte in lead acid batteries pretty toxic?

Only because it’s had chunks of lead bathing in it. Otherwise it’s just sulphuric acid, which is pretty easy to deal with.

 

[wagnerrp]

There is some hope for flow batteries because their storage capacity is independent of the power output. Basically, higher capacity just needs bigger tanks to store the electrolytes so you could have a system where it can cycle daily using only 5 or 10% of the total capacity while reserving the rest of the capacity for more long term shifting. That said if the 5 or 10% is sized to do peak output for a couple hours during evening peak rates for the utility the full 100% would only be a couple days of power stored, at best.

That's an artificial requirement to promote coal and natural gas. You can have enormous piles of coal, and enormous underground caverns filled with natural gas, and that will last you a month or more, but why? If you are cloudy, overbuild your solar and increase your regional transmission. If you're just so cloudy over such a large region that overbuilding solar isn't practical, add wind. Then add more wind. Then start building long range HVDC links to pump energy from somewhere that does have resources. You need infrastructure, and it's not like that coal/gas would be worth a damn without our barge, freight rail, and pipeline networks.

 

[numerobis]

I wonder how some of these technologies compare with the giant lead acid batteries that local telcos used so that landline phones remained working even during a power outage. For those of you who may remember, 50 years ago when power outages occurred, landline phones always remained working. They had giant vats of acid, each one a cell in an array to achieve the desired voltage. As I remember, those cells lasted for decades and I don’t remember them having a lot of drawbacks other than size. For all I know, maybe these batteries are still in use.

I guess my main point and a point brought up by others is that when space isn’t a problem, you don’t necessarily have do use a lot of expensive, exotic materials and engineering to store grid power for use when renewable sources aren’t at peak production.

Lead acid still makes a great backup battery. It does better when kept fully charged, and you don’t expect many power outages over the life of the system.

For daily cycling, which is what these systems aim for, it’s pretty crap because lead acid batteries don’t have particularly good cycle life. And LFP batteries also have cheap inputs.

 

[wagnerrp]

Their power is low relative to their energy. Iirc, it takes 100hrs to discharge. If you have 100MWhr of storage, you can only pull 1MW. If you had 100MWhr of Li-Ion, you could pull up to 100MW.

You may have 100MWh of LiIon cells, but only 10MW of inverters, so you can only pull 10MW, and have a minimum of 10hrs to discharge. There's always extra equipment besides just the storage medium, and that imposes extra constraints on the operation of the battery. The current "sweet spot" for current battery installations is around 4:1, or four hours of battery life at maximum draw.

Flow batteries just take that concept a bit further by separating the storage medium from the cell, as you would a fueled system. You could have one cell with an enormous tank, such that your battery lasts days. You could have ten cells for ten times the power, and your battery only lasts hours. The promise of flow batteries has always been that the cells are the expensive part, so if you just want more storage, the tanks and medium are cheap. The reality of flow batteries is that we haven't yet figured out how to make either cheap (maybe we just haven't spent the necessary investment), and the cells are still expensive.

 

[paulfdietz]

Good luck finding a mountain that you will be allowed, these days, to hack a great big hole into the top of.

I’ve calculated that Li-Ion batteries could do the same thing for about the same price.

Well, just about the entire Basin and Range Province has suitable geography for pumped storage. The White Pine Pumped Storage project I linked before is to be located there, near Ely, Nevada.

This area is under crustal extension, estimated to have been roughly 100% since the start of extension. This causes faults that drop valleys and raise ridges ("horst and graben" geography). Almost anywhere is suitable for locating pumped storage.

I agree Li-ion price drops are placing pumped hydro projects in jeopardy. It's not clear the White Pine project will go forward now, given market realities.

 

[paulfdietz]

[...] LFP uses ... lithium, iron, and phosphates, which are not usually considered "conflict minerals".

And when you hear or read about batteries requiring "rare earths" you are truly seeing FUD. Those are used in permanent magnets for electric motors (for which, also, there are alternatives), but not in batteries.

Just to quibble: a variant of LFP dopes the phosphate with yttrium, so that rare earth is involved.

 

[evan_s]

That's an artificial requirement to promote coal and natural gas. You can have enormous piles of coal, and enormous underground caverns filled with natural gas, and that will last you a month or more, but why? If you are cloudy, overbuild your solar and increase your regional transmission. If you're just so cloudy over such a large region that overbuilding solar isn't practical, add wind. Then add more wind. Then start building long range HVDC links to pump energy from somewhere that does have resources. You need infrastructure, and it's not like that coal/gas would be worth a damn without our barge, freight rail, and pipeline networks.

No. It's just a simple fact. Any asset, not just power generation, that rarely gets used is going to have a very high per unit cost. As far as the grid of the future goes I expect it will include a bit of everything. Overbuilding Solar/wind will happen and in many area's you could say it has already started. CA has more solar production than consumption in the early afternoon on many days. Texas has wind over production at night such that spot prices for power even pushed negative sometimes.

Just overbuilding alone won't be practical because that solar or wind that is only needed in worst case scenarios will never get built because the ROI won't make sense alone. Transmission helps some to average things over a larger area but for practical levels won't handle things on its own. Storage will help and we are already seeing that in CA. Storing that excess solar and wind to help with the peak at night.

I expect that if my theoretical flow battery ever gets put into service what will actually happen is the 10% daily cycling will be combined with deeper cycling as needed throughout the year so the other 90% isn't strictly seasonal cycling but may be tapped into once or twice a month to provide some additional level of power capacity as needed.

Another thing I expect we will see is a lot more controllable or variable demands added. We already see this in early programs that are hitting easy options like electric heating/cooling, BEV charging etc but as we overbuild more and more I expect we will start to see some variable loads built specifically to consume some of that overproduction as cheap electricity for input into processes. It might be hydrogen generation or water desalination or some other thing that we don't even anticipate. I know those have challenges like the capitol cost of building everything and needing to run enough of the time to still make sense but I think something will fit into that niche.

 

[wagnerrp]

My problem with "old obsolete" SLA is its high internal resistance, and how you really shouldn't run it to near 0% SoC, even for deep-cycle batteries. High internal resistance means you can't easily put a prolonged high load on it (voltage dips too quickly at lower SoC), and a reduced depth-of-discharge rate means you're actually only able to access 60-70% of the energy available in lead acid.

Even deep cycle batteries only have access to around 30% of their capacity. If you drop below ~50% SoC, you're damaging the battery. If you're regularly cycling to 100% SoC, you're damaging the battery. You really only want to use a portion in the middle, but then if you do that, you're damaging the battery, and need to take it offline semi-regularly to float it. Lead acid in general is pretty shitty.

LFPs can sit at 100% for a prolonged time without degradation (it's not that your SLAs in UPSes are staying good forever either), and a good BMS with a shunt and proper calibration shouldn't have any issues figuring out pack SoC.

I think this is the biggest complaint about people using SLAs in UPSs. You spend a lot of money on a device that you rarely if ever use, and then five years later when you actually have an outage, that battery you failed to replace per schedule is trash, and the UPS shuts down after just 30 seconds.

Either that, or people completely misunderstand the purpose of a UPS, to give you a little bit of extra time to save and close everything down and/or spin up the generator.

 

[wagnerrp]

No. It's just a simple fact. Any asset, not just power generation, that rarely gets used is going to have a very high per unit cost.

You mean the production of that asset is going to have a higher per-unit cost? The asset itself doesn't cost any more per-unit, and often times costs less per-unit because of the volume purchase.

As far as the grid of the future goes I expect it will include a bit of everything. Overbuilding Solar/wind will happen and in many area's you could say it has already started. CA has more solar production than consumption in the early afternoon on many days. Texas has wind over production at night such that spot prices for power even pushed negative sometimes.

Just overbuilding alone won't be practical because that solar or wind that is only needed in worst case scenarios will never get built because the ROI won't make sense alone. Transmission helps some to average things over a larger area but for practical levels won't handle things on its own. Storage will help and we are already seeing that in CA. Storing that excess solar and wind to help with the peak at night.

Our current levels of electrical transmission only modestly help to average over a larger area, because we spent the last century using rivers, rails, and roads as our primary transmission infrastructure. We bring fuels to the area it needs to be consumed, rather than bringing electricity from what it is being generated. Electrical transmission "doesn't work" to solve these issues, because we don't have the necessary infrastructure to make it work.

We need storage because we designed our grid around energy sources that permitted transportation and provided storage. See the problem? We don't fundamentally need massive amounts of storage, we need transmission. Especially Texas.

Another thing I expect we will see is a lot more controllable or variable demands added. We already see this in early programs that are hitting easy options like electric heating/cooling, BEV charging etc but as we overbuild more and more I expect we will start to see some variable loads built specifically to consume some of that overproduction as cheap electricity for input into processes. It might be hydrogen generation or water desalination or some other thing that we don't even anticipate. I know those have challenges like the capitol cost of building everything and needing to run enough of the time to still make sense but I think something will fit into that niche.

Variable demand is a costly asset that is not always online producing output, making that output cost more. You can play that game on both sides of the problem.

 

[paulfdietz]

I'd very much like to know how long term storage of hydrogen works.

Because it doesn't.

Salt domes.

https://www.powermag.com/want-long-term-energy-storage-look-to-hydrogen/

 

[Stuart Frasier]

Cobalt is the main "conflict mineral" used in Li batteries, but only in certain formulations. Li-(cobalt-containing formulations) batteries have their uses, where high power and energy density are important (like in transportation). With the improvements made to LFP in China (yes, they were invented in the US, but the patents were sold to Chinese companies a long time ago), though, it makes little sense in most grid situations to use the cobalt-containing batteries. LFP uses ... lithium, iron, and phosphates, which are not usually considered "conflict minerals".

I'm hoping to see NMA batteries come along, which get rid of cobalt altogether, and are supposed to perform slightly better than NMC and NCA,.

https://texpowerev.com/ev-technologies/
I can't find any information on how close they are to commercializing it beyond their pilot plant.

 

[DDopson]

Those numbers won't be super interesting here, as they would change vastly with larger scale.

Maybe the best way to get a number like this would be to just add up the raw materials cost, since that's relatively unchanging and can't easily be optimized away like the assembly costs can. I suspect all three of these are quite low from that stand point, not including any rare or expensive ingredients.

Great, so then report:

1. Today's non-competitive cost per MWhr, if one exists, along with a historical trend if it has been improving.
2. The start-up's aspirational at-scale cost target in X years, along with their narrative for how they hope to reach that target.
3. Sanity check with a first-principles analysis of the fundamental costs.

For example, let's do some of that #3 work for sodium sulfer batteries...

While Google's summary reports $300 to $500 per kWhr for sodium-sulfer batteries, it seems that number comes from this 2012 eBook, and Lithium-ion battery prices have improved by >10X over that time period, so did sodium sulfur prices also improve, or is this merely a once-promising also-ran technology that's getting lapped by the superior scaling economics of the dominant tech path? I haven't been able to find an accurate modern price and I can find this article saying that 720MW/5,000MWh of sodium sulfer batteries have been deployed worldwide, and there's at least three deals in development worth another +300 MWhr (only 6% of the installed base, suggesting very slow growth), but I can't find any concrete cost numbers anywhere other than to say BASF's new model is 20% cheaper than the old model.

The raw elemental materials for sodium sulfer are indeed very cheap, on the order of 0.10 / kWhr, which rounds to zero. So that's clearly not where the cost is coming from. Where is the cost coming from?

I found a much older paper, here, probably from the late 80's, and despite the age, it has a good first-principles break-down of the cost structure for these sodium-sulfer batteries. Oddly, it arrives at a total cost of only $112/kWhr, but if those are 1987 dollars, that would be $311 today, suggesting that the prices for sodium sulfer batteries haven't improved in almost four decades and have in fact slowly appreciated at the rate of inflation.

Of that cost, 42% comes from the materials for "Cell Production" and "Battery Assembly", direct labor is less than 4%, and then the remainder comes from various levels of overhead including management, facility cost, sales, distribution, support, warranty, and 24% for "ROI & Taxes". Overheads like those typically have a strong proportionality to the fundamental material and labor costs, so we could say that materials cost seems to be directly or indirectly driving the vast majority of the ultimate price, a surprising counter-argument to the "sodium and sulfer are very cheap" narrative.

What makes the battery materials so expensive? Well, the paper has a breakdown:

Notably, "Seals and Containment" is almost half of the cell materials cost. Storing high-temperature sodium does sound expensive, and not in a way that has improved to nearly the same extent that we've improved our ability to fabricate the incredibly intricate layers of a Lithium-ion battery. Any forward-looking story for this technology should be addressing that topic, especially since it might be difficult to scale the battery capacity by "just" adding more cheap sodium and sulfer if that also incurs a proportional increase in the containment costs.

My primary complaint with this article is that the author had access to representatives from these companies, who should be at least somewhat motivated to get coverage, and the author either failed to ask, or was unable to get any sort of price narrative from them. Perhaps they weren't willing to discuss costs and prices, but then that would be a major red flag worth reporting. If you're a start-up, it's your responsibility to put together an economic case for why the business plan makes sense and has a good chance of achieving sales and profitability. At a bare minimum, such a story could be something like "while costs for this technology are currently too high, they don't need to be, and we are developing a more scalable manufacturing solution that we believe will reduce costs by more than an order of magnitude; in particular, XYZ is most expensive component, and we can fabricate by ...". Any start-up unable to construct such a story and have it sound at least vaguely plausible is going to have a very hard time raising funding. Whether that story is true or not will determine whether the start-up still exists in five years. Lack of a quantitatively grounded story is a major red flag.

 

[m0nckywrench]

There was a fire at a local industrial energy storage site last week which used lithium batteries that has the residents now all up in arms about having fires at industrial energy storage sites. I suspect the sentiment is more about "No fires in my back yard" than it is about the actual safety (or seeming lack thereof) behind industrial energy storage sites.

But if you have this as a selling point:

Then I suspect neighbors would be less intolerant of having them in their back yards. Hard to say, though, since that region of the county is heavily conservative, and they hate anything the liberals like. So it's not just NIMBY, but political NIMBY on top of it.

Fires vary in kind and quality. The public quite reasonably accept ordinary fires because they're (generally) easy to exinguish. Fires which are difficult to stop or contain without specialty equipment and extended firefighter presence are different. Fires which can be stopped early with handheld or even wheeled commercial extinguishers are not the same as self-sustaining fires requiring a well-equipped fire department even to contain.

No sprinkler system can halt lithium ion battery fires. They're wonderful devices of immense value to the modern world but frequency of fire is not kind and quality of fire. Common and commonly controllable fire is different from less common, difficult to control fire.

Have some NFPA: https://afdc.energy.gov/case/3133

 

[CosmicTourist]

StorEn Technologies of Greenville, SC is developing a vanadium flow battery system that can address home residential as well as industrial and larger-scale projects. Vanadium flow batteries can be discharged 100% over and over without losing their capabilities, and they have an estimated lifespan of 25 years or more. Also the electrolyte can be recycled into new batteries and doesn't suffer from the costs required to recycle LiON batteries.

 

[Geburtenfresser]

I'm not an expert in this area... but what about just pumping a lot of seawater up a mountain, and then slowly releasing it through a turbine generator whenever you need more electricity? There's no loss of stored energy over time like with chemical batteries.

Side benefit: if you happen to have extra energy, you can use the water pressure to push that seawater through reverse-osmosis filters and get freshwater, which is scarce in certain parts of the country, like California.

Is anyone doing something like this already?

No, you just came up with that. Congrats.

 

[wagnerrp]

Fires vary in kind and quality. The public quite reasonably accept ordinary fires because they're (generally) easy to exinguish. Fires which are difficult to stop or contain without specialty equipment and extended firefighter presence are different. Fires which can be stopped early with handheld or even wheeled commercial extinguishers are not the same as self-sustaining fires requiring a well-equipped fire department even to contain.

No sprinkler system can halt lithium ion battery fires. They're wonderful devices of immense value to the modern world but frequency of fire is not kind and quality of fire. Common and commonly controllable fire is different from less common, difficult to control fire.

Have some NFPA: https://afdc.energy.gov/case/3133

Then why even try? Treat it like various other industrial hazardous materials and abandon control for mere containment. Pass standards that require spacing or revetments and a berm such that one failed unit will not spread to others.

 

[THT]

So I have the same musing a lot of you do - we used about 16.5 [MWH] of power in the last year at my home, and so I would have loved to see more details about how many MWH/etc. these things could provide. As somebody else mentioned above:

Yes, you can currently get generators that run on LNG/etc. around here for the occasional power outage, but imagine if every home had a "power bank" that could power their house for upto 6-12 months during a power outage. And even in communities with smaller lots, a "small" one of these providing upto a 1-3 month supply? Especially with a wide solar initiative, it seems like we could then really focus on optimizing our power grid and lowering costs. (Not that the privatized monopolistic power companies in the US would allow it, but....)


All that aside, it's cool to watch how the power storage industry is moving forward esp. with advances in car and solar technology. Slow but steady progress!

From the article for the sulphur-sodium flow battery: "The batteries are packaged in 20-foot-long shipping containers that has six modules that collectively provide 1.45 megawatt-hours, Brannock said. The shipping containers are usually used in groups of four."

Doesn't seem tenable for seasonal usage for a home, unless you have a couple of acres. Scale it down to 100 kWH, maybe it is as big as 2 or 3 refrigerators? And, batteries will need to provide enough power for air conditioners where I live. Delivering a lot of power isn't a strong feature for flow batteries.

Solar+storage + V2G will pretty much do it for your house though. Get yourself about 12 to 15 kW of solar, 40 kWH of battery (likely LFP for a while), and 80 to 100 kWH in your car, you are basically set for days to weeks on end. Cloudy to rainy for several days in a row, just go charge your car and you'd be set for two or more days, repeat until it is sunny enough. Assuming the grid is out for a long time, that is.

 

[zaco]

I don't think that flow batteries seem that compelling due to the cost and need of constant maintenance. And, this is something the article didn't critically examine; it seemed to take the statements downplaying maintenance requirement from the company's reps at face value. From the article:

The batteries typically use an annual maintenance program to replace components that wear out or fail, something that’s not possible with many other battery types.

For maintenance, CMBlu Energy recommends regular visual inspections, including checking the pumps and valves and looking for leaks—the maintenance requirements are relatively minimal

Any grid-scale energy storage facility is going to have maintenance, advertising the annual contracts seems to indicate the scale of the maintenance here is a bit more. Flow batteries require replacement membranes and pumps on a regular basis because they are constantly in contact with corrosive liquid electrolytes. The electrolyte and electrodes also need to be replenished or replaced, though less frequently. I would think that a flow storage facility would need plumbers, electricians, and probably chemists to maintain the various systems, while a Li storage really just needs electricians. Is this cheaper than replacing cells/cell packs as they fail in Li storage?

Zinc bromine is perhaps a safe chemistry, though elemental bromine is pretty toxic so good containment is still important, but it won't burn your neighborhood down. As for the iron flow or vanadium flow, they also kinda have the same containment problems, very corrosive or toxic electrolytes in large volumes is going to be expensive to handle. I think if the chemistry works then you could just make traditional battery cells out of it and save all the trouble with the flow system.

If the zinc bromide is a value-added product from the oil and gas industry, is that actually a good thing? Would scaling this technology up be cost effective or ethically justified along side a (hopeful) transition away from fossil fuel production?

Edit: It sounds like they plan to sell the used electrolyte to the oil and gas industry and not recycle used zinc bromide. Either way the association seems dubious and requires a bit more explanation.