An open-source flow battery kit

Wow, hi all, I am Kirk, the author of this blogpost, never thought my small ARM board home server would handle this much traffic!

Currently reading through these posts, feel free to ask questions. Great to see interest.

FYI, I am quitting my postdoc job in two months to work on this full-time, which should help the rate of progress, but my main source of income will stop. We hav ea small but it will only cover a few months of full-time work.

If you want to support the project financially we have an Open Collective here: https://opencollective.com/fbrc/donate

We'd really appreciate any support you're able to give, which we'll use to push this open technology as far as we can! We are planning to start work on a much bigger stack after the kit.

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.

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 college campus) and utility scale customers.

So many promising products and technologies die because the inventors/developers hold out for huge customers while ignoring the huge demand from retail/small/medium corp customers.

"We won't talk to anyone except corporations with deep pockets. Once we find a couple of those, we'll be filthy stinking rich!" instead of "if we sell the components at a price that undercuts LiFePO4, we'll have as many customers as we can handle, and there's plenty of margin for distributors and retailers, so we don't have to be B2C."

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 get out of a small setup like this?

Looks like a cool project!

It would be helpful to start the article with a link to why flow batteries are amazing.

I cannot see how this is useful outside of being a fun student learning program.

From the data it appears a battery with 1L of electrolyte provides about 18Wh of energy. Mind you this is at ~1.2V, which isn't especially useful without a boost converter. With a boost converter though you would need a low internal impedance from the battery, which I highly doubt is any good with a paper membrane (from what I understand it already isn't great for flow batteries).

Meanwhile a pair of 18650 lithium ion batteries can be had for $5 and can provide 24Wh at a very usable 7V with no power conditioning or a range of voltages with more than enough ability to source current. And it is a fraction the size, weight, and complexity.

I don't mean to tear apart the project, perhaps there is a key detail I am missing, but I just don't see what this is trying to do outside being a learning experience for students.

Can this be combined with uphill water storage so you store both kinetic and chemical energy? The pump would store water uphill as it does now, but when it flows down it goes through the membrane and also generates power this way? Of course it robs some of the momentum used for the turbines but idk, maybe it’s more efficient?

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.

What is the Coulombic efficiency? A paper membrane probably leaks a lot, but a state of the art ion exchange membrane probably runs $1k/m2.

Hi! Just to say that Symantec doen not like your website! Malicious Site Blocked! Symantec Endpoint Protection blocked this website: https://dualpower.supply/