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i'm familiar with the destructive power and unpredictable nature of hydrogen detonations, yes ;) but that's what happens when you don't vent the hydrogen to the atmosphere
Yes, but improperly venting the hydrogen is "not venting hydrogen" but looks like venting the hydrogen unless closely inspected.
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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...
you can just vent h2 to the atmosphere
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you can just vent h2 to the atmosphere
It doesn't work so easily; if you do that, the battery itself will fall apart because of deposition of the iron. See: https://iopscience.iop.org/article/10.1149/1945-7111/abcf50/...
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A flow battery isn't going to burst into extremely high temperature flames in a self-sustaining not easily extinguishable fire that also spews toxic fumes in mass quantities. I'll take a basement (or garage) with a flow battery over lithium ion ANY day of the week if I want battery backup for my house.
You would not use a laptop-style lithium battery for battery backup for your home. You would use LFP. It does not have the burst-into-flame problem you are thinking of. At some point I expect we will look back at the era when we used really flammable electrolytes and laugh about how wild that was. I bet we are not that far from it being just a memory.
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Why wouldn't you take a scratch-build EV on the road? People build kit-cars all the time, and an EV has a much simpler control system. This is a very simplified project to prove the concept and provide a test bed for further exploration, not an end-product by any stretch. This seems like the perfect project to test various membranes and electrolyte solutions.
>Why wouldn't you take a scratch-build EV on the road? Because you don't want to snap your spine in a minor fender bender. Scratch built is not the same thing as an EV conversion kit, where all the hard stuff (like a frame and body panels) was already made by commercial manufacturers. This flow battery is from scratch (well except for the pumps and electronics, but the cell itself is). They are not using off the shel…
https://www.solarcarchallenge.org/challenge/about.shtml
https://www.solarcarchallenge.org/challenge/docs/rules2023.p...
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…
So, in this case both are a bit underwhelming obviously. But the main point is that you can increase the kwh by simply using bigger tanks and the kw by using multiple cells in parallel or by improving the anode/cathode somehow.
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…
For example by just working with a handful of customers. Or by building a tiny factory that merely prove technical feasibility instead of a bigger one that would prove the business case as well as the technology benefits in terms of cost. Big battery factories are expensive and risky. And most battery tech doesn't really get profitable until you have a big factory and a few years of optimization. The price of the first batteries is generally really high and it can take years to get there.
This has been a problem with battery tech in particular where mostly companies in the US or Europe don't get much funding for new tech and where China actually seems to be doing a bit better. Which is why sodium batteries are shipping in China (CATL) and sort of stuck in R&D for many years elsewhere.
With flow batteries, the technology is kind of proven at this point. They work, they exist, etc. What's left to prove is the price point: can it be done cheaply? Everything seems to suggest yes. But proving that is going to require scaling production and a massive amount of investment to get that going. Think billions, not millions.
Small retail customers are not helpful here because those don't pay until after the factory gets built and starts shipping product. Demand is never the issue. It's doing the leg work to get to the promised price point at which that demand exists. That requires investment.
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>Why wouldn't you take a scratch-build EV on the road? Because you don't want to snap your spine in a minor fender bender. Scratch built is not the same thing as an EV conversion kit, where all the hard stuff (like a frame and body panels) was already made by commercial manufacturers. This flow battery is from scratch (well except for the pumps and electronics, but the cell itself is). They are not using off the shel…
Every other year, (solar-)electric cars scratch-built by high school students drive on public roads from Texas to (usually) California. This is considered a reasonable level of challenge, and something which insurers will cover (entrants are required to have vehicle liability insurance). https://www.solarcarchallenge.org/challenge/about.shtml https://www.solarcarchallenge.org/challenge/docs/rules2023.p...
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…