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An open-source flow battery kit

dualpower.supply

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Re: An open-source flow battery kit

#31

Post by hlieberman »

KennyBlanken wrote: post #17

I've been watching ESS (they make a non-toxic iron flow battery system) for years and been really frustrated that they have made essentially zero progress deploying the technology, with less than half a dozen deployments. The technology looks great, but they seem annoyingly incompetent at marketing/selling their product...or are just holding out for "whale" customers, refusing to work with anyone except microgrid (ie…

The author actually talks about ESS in a comment to the linked blog post from the article. Apparently their battery generates a ton of H_2 that needs to be managed. That could easily be the sort of thing that only is possible/realistic at large scales, thus eliminating sizing the battery down indirectly. https://chemisting.com/2024/03/15/an-open-source-diy-flow-ba...

Re: An open-source flow battery kit

#32

Post by sterlind »

mikewarot wrote: post #30

It's my understanding that iodine is one of those things watched very closely by the TLAs enforcing prohibition. Be careful, lest you end up unable to move about freely because this gets you on a list.

Iodine used to be commonly used to reduce pseudoephedrine to meth, but these days most meth comes from superlabs in Mexico, who use a very different process. I doubt you'll catch much heat for it these days, especially since it has a number of legit uses. And even if it gets you on a "list" you're more likely to just get raided once rather than no-fly'd.

Re: An open-source flow battery kit

#33

Post by briffle »

0cf8612b2e1e wrote: post #27
ForOldHack wrote: post #25

Earlier quoted context omitted.

There are two key details you are missing: 1) Its scalable to dishwasher size, ( enough to power a tiny house ) 2) If you shot it with a bullet, it would just leak salt water. That is all. Lithium Ion will explode: Now here is the quiz: If you have a cell phone that is inflating, do you A) Dunk it in water? or B) Toss it in a full document safe? or c) Quickly empty your document safe, and toss it in? If a flow batter…

… if you are looking to scale this to a couple of hundred megawatts, just stop reading and thinking about this now I thought that was one huge appeal of flow batteries is that you can basically infinitely scale them. China has a 100MW installation (potentially more since this 2022 report) https://www.pv-magazine.com/2022/09/29/china-connects-worlds...

These guys in the US make a 500kwh version, that can run at 75kw of discharge power across 3 phases, and its a single shipping container: https://essinc.com/energy-warehouse/

It doesn't seem like it would take up that much space to have 200 shipping containers sitting somewhere, i'm pretty sure the Home Depot distrubution center in our town already is close to that in their parking lot (yes, you would want them not on wheels, and farther apart)

Re: An open-source flow battery kit

#34

Post by Workaccount2 »

Retric wrote: post #28
Workaccount2 wrote: post #13

Earlier quoted context omitted.

>Also, the internal resistance depends entirely on how many cells you have. Right, from the one study I can find, commercial flow batteries have about 10-20x the internal resistance of a lithium ion battery, so the match the power and energy capabilities of a single li-ion cell you would need a liter of electrolyte and about 30 (!) cells (3 for voltage x 10 for power). And that is for a commercial quality flow batter…

1 liter of electrolyte is nothing for a flow battery, the smallest scale they become a serious competitor is ~10m3 (10,000L) tanks which are ~(7 foot X 7 foot X 7 foot). Start taking GWh of storage and lithium ion technology gets really expensive and has a lot of associated risks. Flow batteries on the other hand don’t need to worry about a single cell failure resulting in a fire which then spreads.

The amount of electrolyte doesn't scale the available power though, only the available energy.

Re: An open-source flow battery kit

#35

Post by Workaccount2 »

Dylan16807 wrote: post #22
Workaccount2 wrote: post #13

Earlier quoted context omitted.

>Also, the internal resistance depends entirely on how many cells you have. Right, from the one study I can find, commercial flow batteries have about 10-20x the internal resistance of a lithium ion battery, so the match the power and energy capabilities of a single li-ion cell you would need a liter of electrolyte and about 30 (!) cells (3 for voltage x 10 for power). And that is for a commercial quality flow batter…

Unless you're flying a drone, you don't need to match the power and energy capabilities of lithium ion. On top of that, you don't have to match the internal resistance to match power. If you have plenty of material to absorb the heat, then you can tolerate more percentage points of loss. In particular, while lithium ion batteries can be built to sacrifice discharge rate for a bit of extra capacity, something like a 3…

I see what you are saying, in reality the right energy storage is very application dependent. The crux of my argument is that I cannot think of many applications where a commercial grade flow battery is the best choice, much less a single application where a DIY flow battery is the best choice.

Re: An open-source flow battery kit

#36

Post by Workaccount2 »

mschuster91 wrote: post #26
Workaccount2 wrote: post #13

Earlier quoted context omitted.

>Also, the internal resistance depends entirely on how many cells you have. Right, from the one study I can find, commercial flow batteries have about 10-20x the internal resistance of a lithium ion battery, so the match the power and energy capabilities of a single li-ion cell you would need a liter of electrolyte and about 30 (!) cells (3 for voltage x 10 for power). And that is for a commercial quality flow batter…

> I'm not trying to say flow batteries are stupid or dumb, but their use cases are going to be very limited without some huge breakthroughs that will probably dramatically increase the complexity too. The largest use case is going to be grid scale storage, and for that one a bunch of dumb tanks and a bank of cells are far easier to handle and less risky than a bunch of li-ion cells that can go into runaway for whatev…

The thing is that there are like 50 other options for energy storage, it's not just lithium-ion that flow batteries have to out compete. Everything from electrolyzed hydrogen, to hot sand, to air pressure tanks, to sodium-ion and zinc air and LiFePo batteries.

Flow batteries are cool because the storage element is extremely easy to scale. But its not even that great because you also need to scale the amount of cells dramatically to make it useful outside of edge cases. At which point it probably makes more sense to just use another storage mechanism.

Re: An open-source flow battery kit

#37

Post by moffkalast »

RobotToaster wrote: post #29
perlgeek wrote: post #8

Lots of software started this way: as a toy, a proof-of-concept, a learning opportunity for the programmers. I really hope that they find interested people who join their experiments, and build something awesome and open together.

Home 3d printers started as repraps that could barely print a shot glass.

That wasn't because it was a proof of concept tech, but because Stratasys was effectively patent trolling it since the 80s.

Re: An open-source flow battery kit

#38

Post by moffkalast »

_alex_ wrote: post #20

I dont know anything about flow batteries, but some quick searching leads me to believe that there are two tanks of electrolytes with pumps that pump them along a membrane and then you get power across the membrane. In this small battery kit, is the idea that the battery provides enough power to both operate all its own pumps/electronics, and then output usable power? Does anyone know how much power you'd be able to…

Definitely looks like a great idea, fuel cells with something that doesn't outright explode if you look at it wrong. The shortcoming would be the energy density I would expect. But even so if there's something that can maybe be half as good as lithium but can be refuelled in seconds by just filling up a tank there's definitely a market for it.

Re: An open-source flow battery kit

#39

Post by smallerize »

ForOldHack wrote: post #24
perlgeek wrote: post #8

Lots of software started this way: as a toy, a proof-of-concept, a learning opportunity for the programmers. I really hope that they find interested people who join their experiments, and build something awesome and open together.

This looks like a toy, but its INSANELY COOL! You build a proof of concept? This technology is cool. I was at a tiny house competition, and we were using golf cart batteries, and the winner: The University of Santa Clara, CA: "The house stores its energy using saltwater batteries, the only batteries in the world to be Cradle to Cradle certified." https://www.tinyhousebasics.com/revolve/

That article is from 8 years ago. Saltwater batteries are hard to find right now since Aquion quit making them and I don't know of anyone retailing Salgenx yet.

Re: An open-source flow battery kit

#40

Post by almostnormal »

Workaccount2 wrote: post #34
Retric wrote: post #28

Earlier quoted context omitted.

1 liter of electrolyte is nothing for a flow battery, the smallest scale they become a serious competitor is ~10m3 (10,000L) tanks which are ~(7 foot X 7 foot X 7 foot). Start taking GWh of storage and lithium ion technology gets really expensive and has a lot of associated risks. Flow batteries on the other hand don’t need to worry about a single cell failure resulting in a fire which then spreads.

The amount of electrolyte doesn't scale the available power though, only the available energy.

Energy storage is the problem that needs a solution, e.g., storage from summer to winter.
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