Battery made of aluminum, sulfur and salt proves fast, safe and low-cost
newatlas.comAt this point I strongly distrust any 'breakthrough' article about research at MIT. After hundreds of these, I'm fairly convinced that any time a grad student pours liquid into a beaker, MIT's marketing department is out publishing the fact that Flubber has just been invented and we're all going to be saved by bouncy flying automobiles.
I mean, congrats on the great marketing department. But it's tiring to be disappointed over and over by the hype.
Views like this are common amongst STEM types, but they vastly underestimate the importance that science communication plays in getting the public on board with science funding.
These are articles for taxpayers, not for you.
A scientist who is also an effective communicator can be 10-100x more effective than one who only publishes in journals, because it can build consensus to fund large projects and get champions and stakeholders.
That's lovely, but if this is not even effective communication.
Very frustrating that the article entirely fails to provide key information about its main topic - batteries. They even fail to provide even rough order-of magnitude values.
How much energy can it store, i.e., the energy density (watt-hours per kilogram or equivalent measure)?
How much power can it put out per unit mass (watts per kilogram or equivalent measure)?
What level of cost (e.g., dollars per kilogram) are we talking about?
Sure, they talk about some new feature, but without at least a rough order of magnitude on these key parameters, we cannot even guess at what will be the valid applications. For example, a battery with a very modest energy & power density but really cheap will be worthless for transport or airborne applications but may be great for fixed storage, and many other combinations.
But with only highlighting some new feature in isolation, the only possible audience is ignorant enthusiasts, who we hope are not making policy.
I used to be really enthusiastic about most new battery tech articles, but at this point, if they fail to even mention one of those three parameters, it looks to me just like clickbait or spam.
<quote>These are articles for taxpayers, not for you.</quote>
Are they? Taxpayers don't decide where their taxes go.
Am I not also a taxpayer?
Ars [1] has a pretty decent article with a bit more depth. Still no mention of the cell's basic voltage which I thought was like the number one piece of information for a new battery chemistry.
[1]: https://arstechnica.com/science/2022/08/new-aluminum-sulfur-...
I mean, the actual paper being discussed probably has the information you want - even if the Ars article doesn't
Probably 1.2 V, like any classic cell. I mean take one zinc and one copper disc, put some paper between them, spill citric acid onto said paper and voial!, you got yourself a battery cell.
From what I can recall of high-school chemistry, it depends on which ions are being used, and generally different for each combination. The basic zinc-manganese dioxide cell has an EMF of about 1.5V, while lead-acid car battery cells give about 2V.
https://www.pveducation.org/pvcdrom/battery-characteristics/...
https://www.pveducation.org/pvcdrom/battery-basics/electroch...
Update: I see it also depends on their concentration, so the voltage changes as the cell discharges, unless all the components are solids:
https://www.pveducation.org/pvcdrom/battery-basics/nernst-eq...
When I say classic, I meant the classic from 1800's, you know when Volta, Faraday and other were experimenting with different wet/dry electrolytes between the zinc/copper discs. Citric acid as electrolyte holds 1.2V and is easy to buy from you local supermarket.
So there you have a third datum confirming that the voltage is dependent on the materials used.
> The team says that this battery design would be best suited to the scale of a few dozen kilowatt-hours, like powering an individual home from renewable sources.
I'm curious to know if this would also be suitable for grid-scale storage, it seems like an odd ommision in the article. The description certainly implies that this would be a good use but I wonder if there is an issue that I'm not seeing that would make them less useful for that?
Not being flamable sounds like a good thing for house and charging station level storage, although heat management might be an issue in smaller houses. I've always been a bit uncomfortable about the idea of a large li-ion battery pack in my house, given the difficulty of extinguishing fires that involve them, I'd be happier with something like this assuming the thermal management could be dealt with.
> I've always been a bit uncomfortable about the idea of a large li-ion battery pack in my house
So am I, but I think we're not different from people who are afraid of using planes. Yes, it's really bad when it happens, it just doesn't happen all that often and when it does it ends up in the news. Just like cars are more dangerous than planes even when you have li-ion battery it probably has very low impact on total probability of your house burning down because of other potential sources.
Plus somehow people seem to be afraid of wall mounted battery while having no problem with EV car parked in the garage.
I guess it depends on how hard it is to move. At least when GM tells people not to park their Bolt inside or near flammable stuff, they can move it. I image it would be difficult to do that with a battery pack whether connected to the wall or not.
You could always mount it on wheels, which would be way way easier than moving a car that's on fire (you can even keep big wire cutters nearby)
If fire hazard is what's stopping people I guess one could also build a fire-resistant brick cage around it (presumably just a shelf on top should be enough? so that it still can stay cool during normal operation)
Especially since they tend to be installed in garages, that would be my plan if I get one. Building stuff with casters is something commonly do for my basement or garage.
The idea isn't to move it when it's on fire, but that if a recall is issued, then you can at least move it out of the structure in case it does ignite.
That makes it a lot more likely to move and be damaged/catch on fire due to an earthquake though.
If you live in a region we're that is a concern, then the answer to this problem shojld also be appearent to you. You can still have it on casters and achor it in others ways, such as ratchet straps and floor anchors.
In which case, there is zero need for casters. It’s easy to move even multi-ton stuff on flat floors with dowels.
Provided you can lift them on dowels, or that you leave them on.
For anyone considering this - it’s a lot easier than you think, and with basic hand tools it takes minutes to move something as long as you can get a prybar under it and know the fundamentals. but if there is a chance you can tip it onto yourself (say, a large multi-ton safe), call some safe movers instead of doing it yourself. Don’t be red goo.
Easier to make an impromptu firebreak between a car and the house, than a battery pack presumably securely mounted to the wall of the house.
From the article itself:
> Other types of batteries, such as a recent design using molten salt electrolyte and aluminum and nickel electrodes, could work better at grid scale.
Huh, weird. I definitely read the article and just that bit just didn't register! Weird.
Would still be interesting to see if this can be made to work well at grid scale, feels like we need as many different technologies so we minimise specific resource constraints.
I think I'd have even bigger concerns about a battery hitting 230F as part of normal operation in my house. Maybe they can create a dual use as a preheater for the water heater or something.
That is not so different from the tank water heaters that most houses have. The water isn’t 230F but it is still a tank of very hot water sitting in your closet or basement. Insulation and isolation would be key.
The challenge of course is scale. It is very easy to build a high powered and fast charging batteries as a one-off in a lab. Trying to produce a million a month is an altogether different proposition.
Sure, but if it can't be done in a lab, it can't be done in a factory.
Hear hear, the next breakthrough like the last 20 ones we had in the last ten years.
Though it's still Li-Ion, LiFePo and plain old Lead Acid in practice.
The Li-Ion battery that you have today is much better than the one you had 10 years ago. All battery tech has been improving year over year for a couple of decades now. We just don’t notice because the yearly change is not so large. New chemistries don’t come into play as often as it takes longer to work out the details and to make them ready for wide spread use.
https://arstechnica.com/science/2021/05/eternally-five-years...
Sodium ion is looking pretty promising.
> Though it's still Li-Ion, LiFePo and plain old Lead Acid in practice.
LiFePO4 is a type of lithium-ion battery. There are also plenty of others. In 20 years cost has decreased to a tiny fraction and gravimetric density (kWh/kg) has increased 3-4x.
No information about energy density and vague information about "..the new battery cells can withstand hundreds of charge cycles, and charge very quickly..."
So it does not have enough density and thus useless in BEVs and if amount of charge cycles is not counted in thousands, then it is kind of useless for renewable storage as well. But at least it is cheap.
> useless for renewable storage as well
If it's cheap enough, it might still be useful in a some sort of hybrid setting. Use this one after a more durable battery is almost exhausted. This way you'd get less cycles overall, but still have power when it's really needed.
Other way to look at it is if this one is 10 times cheaper per kWh, then you might prefer this over a more durable battery.
People with the paper quote 50mAh/g to 500mAh/g depending on charge rate for some reason (not discharge?). Which would give it slightly higher volumetric energy density but worse mass.
li-ion has 70-100mAh/g based on my estimation? so if they can do 200mAh/g that would be very nice, but what about the voltage, charge cycle lifespan and maximum discharge rate?
Voltage is 1.2. I couldn't understand the claims about charge cycle (I think the tests were of 100s of charges, but the discharge rate was variable). Discharge rates were up to 200D, but no explicit mention of internal resistance.
I think this was more of a 'we tried the thing' paper to justify whatever funding they had and now it'll all be hush hush until they think they have a product.
It's being commercialized by the same people that did ambri which looked like a very promising technology at the time with one hard materials problem then they went dark.
The ingredients are cheap and common; just recycle them after a coupla hundred cycles. Maybe you could even refurbish these things at home. The article didn't mention any exotic or expensive materials or parts, so perhaps you could even build your own. Which wouldn't infringe any patents, as long as you didn't sell the thing.
"They can not only operate at high temperatures of up to 200 °C (392 °F) but they actually work better when hotter – at 110 °C (230 °F), the batteries charged 25 times faster than they did at 25 °C (77 °F). Importantly, the researchers say the battery doesn’t need any external energy to reach this elevated temperature – its usual cycle of charging and discharging is enough to keep it that warm."
I feel like they're willing to hype anything. I'm sure this would be good for certain niche applications, but a standard operating temperature that high rules out a ton of uses and requires its own safety considerations.
I have no idea of the chemical reactions, but generally heat means wasted energy. I wonder what the efficiency is like for charge/discharge. And if they're used on a large scale how that heat dissipation would effect the local environment or climate change.
Internal combustion engines regularly get that hot. It isn't hot enough to damage any commonly used metals.
But do you want that in a phone, in your pocket? Or any other electrical device? Or producing that heat in your house?
Obviously this isn't for cell phones. There's no requirement to store batteries inside one's house. It's common to locate problematic equipment and supplies in unconnected sheds. I see lots of outdoor furnaces when I drive around my local area.
I regularly heat things in and near my house to 350º, 450º or even 600º F. It's called cooking. I'm pretty sure if I look at my water heater or clothes dryer the point heat source raising the temperature there is well over 200º F as well.
Yeah, and those aren't constantly on, some require outside venting and/or insulation. They also don't constitute the majority of a wall. There's a reason old timey kitchens were outdoors in the hot areas.
All I'm saying is that there are other concerns with this battery vs a lithium battery, and that I feel the concerns are much lower with lithium.
I'm more concerned about the battery itself bursting into flame on my wall, frankly, than having a battery that needs some insulation and a metal enclosure between it and air-conditioned space. Lithium batteries can do that. They say this one can't. Either way, safety steps should be taken before putting a battery in a pile of oily rags or anything.
Eh, that's exceedingly rare. I wouldn't be surprised if defects in the mass manufacturing of the new battery produces rare fire hazards too. I assume the thermal expansion and contraction of the containment materials will lead to issues too (I've seen it in even cooler operation temps for other batteries). Lithium sulfur batteries are supposed to be fire safe too. I assume there are other options out there as well, stuff with thousands of cycles vs hundreds.
It will be interesting to see how it pans out over the next decade, if it becomes commercially available at all.
I imagine before it hits any markets (if ever of course) refinements would increase the recharge cycle limit somewhat. They used to be lower on lithium, too. We used to use NiCad and NiMH too. I'm just saying that level of heat is not a deal killer for a fixed position residential application.
You might have a tank water heater in your home that holds a large quantity of very hot water 24/7. Not quite to this level but in the same scale. That water heater is insulated and doesn’t prove a problem due to heat.
Eventually you'll heat soak the insulation. With a waterheater, you have new water moving in as you use the previously heated on. The loss may be minimal, but still an efficiency drain half the year. Either way, you to pay for the housing and insulation. Then pay for a replacement battery every year or two.
Why would you need to pay for a replacement battery? These aluminum batteries are specifically designed for long lifetimes. the operating tempurature is not a detriment to the battery.
If you're using a cycle a day, it would deteriorate to 80% capacity in just 200 days. The article says it lasts a few hundred cycles. That's not very long.
The tempature isn't a detriment to the battery, in fact it's required to operate efficiently. What it does limit is the suitable applications.
These would probably not be suitable for phones, but would be suitable for a local power bank for a house and probably also for a car. Where they might really find a place would be for grid scale power storage for solar and wind.
Pretty sure the article said there are better options for grid storage.
I doubt this would be a good candidate for vehicles due to the minimum operating temperature. Certainly vehicle design would have to change to accommodate the different pattern configuration with all the required insulation.
Houses make the most sense, but not for more than emergency power given the battery life is hundreds of cycles and not thousands. Come to think of it, the need to keep it at the minimum operating temperature makes it a poor choice for emergency power too.
> Or producing that heat in your house?
Yes please, today if you can deliver. A combination battery / heater / heat pump sounds amazing.
Only if the climate is cold enough to need it in the summer, or a mechanism to avoid the heat in the summer. And of course, if it's more efficient than other sources, like heat pumps.
Sounds like you could put them in a data center...
So I need a kettle of boiling water to warm up the battery in my electric bike, before I can ride off in the morning? Also, boiling-hot molten salt - I don't want that spilling on me in the event the battery is ruptured in a collision.
(Sure, I don't really want lithium salts splashing on me either; but molten salt at 90C?)
For finicky people like you sire, we have the sodium-sulphur battery that works at room temperature - https://www.thehindu.com/sci-tech/science/iit-m-designs-room... ...
Would this also be a lot easier / safer to recycle?
That is one of the main claimed advantages, because the main components are simple inorganic substances, and not e.g. complex organic solvents that degrade in time, like in most lithium batteries.
Thanks, I scanned the article and searched for the word "recycle" but it wasn't clear.
Battery "breakthrough"s are a dime a dozen. There are usually fatal flaws.
Wake me up when you can buy them.
...so it's probably huge then?
Maybe not THAT huge, just not, pocket sized.
There's a hint here:
"The cells would cost just one sixth of the price of a similar-sized lithium-ion cell."
one thing I'd have liked that I didn't spot was a joules/kg or joules/volume question, and "size" is a bit nebulous, are they talking volume or energy? if it's 1/6th cost per volume, but it's 1/7th the energy per volume, lithium would still come out ahead on cost. It's probably not, but the article and the abstract didn't clarify that to my read.
For the same energy, the mass of an aluminum electrode would need to be almost 2.4 times greater than the mass of a lithium electrode, in a sulfur-based battery (the ratio can be computed from the enthalpies of the 2 sulfides, the atomic masses of Li and Al, and their number of valence electrons).
However, while there are also lithium-sulfur batteries in development, the current lithium-ion rechargeable batteries with Co/Ni/Mn/Fe electrodes have a much worse energy/mass ratio than a lithium-sulfur battery.
Moreover, in a lithium-ion battery, the mass of the electrode which stores the lithium is much greater than the mass of the stored lithium (which is intercalated in a porous structure), and the mass of the electrode is only a small fraction of the total mass of the battery.
The proposed aluminum-sulfur battery needs good thermal insulation, which will increase the volume in comparison with a lithium battery, but which should not increase much the mass.
In conclusion, it is likely that it should be possible to make such a battery at a similar energy per mass with the current Li-ion batteries, but at a worse energy per volume.
There is a chance to improve the energy per volume by making a very large battery, which would be possible because there is less risk of fires, but in a large battery the regrowth of the aluminum might be not uniform enough, resulting in a shorter number of charge-discharge cycles until degradation.
You don't have to insulate each module so one would think that last part isn't a consideration
Maybe this is too hard to quantify outside of mass-production?
I'd assume that a well-tuned mass-production cycle would drastically reduce size over time, like it did with lithium batteries?
So more expensive than lead acid? I think lead acid batteries are about 1 tenth the cost of lithium
The lead acid capacity numbers are a bit of a lie, though. With Li-ion, you can use 80-90% of the nominal capacity. With lead acid, if you do that with any regularity, you will quickly destroy the battery. Lead acid likes to be used in a narrow SoC range around 100%.
Sounds it. But as the article points out, this is probably more suitable for static installations like houses or charging stations, not in your car or phone.
"its usual cycle of charging and discharging is enough to keep it that warm."
Sounds like thermal loss to me...
Now it’s time for MIT or the like to correspondingly design a high-torque 1.5VDC electric motor.
Doesn't salt corrode aluminum? Maybe not these specific salts?
I'll buy twelve.