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Battery made of aluminum, sulfur and salt proves fast, safe and low-cost

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11–20 of 79 posts

Re: Battery made of aluminum, sulfur and salt proves fast, safe and low-cost

#11
post #8
post #4

...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.

Re: Battery made of aluminum, sulfur and salt proves fast, safe and low-cost

#12
post #3

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.

Re: Battery made of aluminum, sulfur and salt proves fast, safe and low-cost

#13
post #10

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-...

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.

Re: Battery made of aluminum, sulfur and salt proves fast, safe and low-cost

#15
post #10

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-...

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.

The classic cell has 1.5V.

Re: Battery made of aluminum, sulfur and salt proves fast, safe and low-cost

#16
post #5

> 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 th…

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.

Re: Battery made of aluminum, sulfur and salt proves fast, safe and low-cost

#17
post #10

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-...

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...

Re: Battery made of aluminum, sulfur and salt proves fast, safe and low-cost

#18
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.

Re: Battery made of aluminum, sulfur and salt proves fast, safe and low-cost

#19
post #8

Earlier quoted context omitted.

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.

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?

Re: Battery made of aluminum, sulfur and salt proves fast, safe and low-cost

#20
post #8

Earlier quoted context omitted.

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.

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