Flow Battery Research Collective

Video of the talk is now available here! https://video.fosdem.org/2026/aw1126/3EEZZB-open-source-batteries.av1.webm

I'm in the middle of Southern Africa, so part of it is making sure I can import the required equipment. I'm also looking for "How I would do it" bearing in mind my lack of decades of experience. I've rebalanced the system once on purpose but would prefer to have the right pumps, acid resistant fittings, valves, T connections and so on.

Time-stamping the electrolyte formulation for Zn-I, I am making the documentation to build the dev kit chemistry agnostic (so I am taking these weights out of the docs for now) zinc chloride - 1.36 grams potassium iodide - 3.32 grams ammonium chloride - 1.07 grams deionized water - 8.50 grams triethylene glycol - 0.55 grams This usually ends up preparing around 11 mL of solution which we split evenly between the two reservoirs.

I'm no chemist, so this may not apply here, but I've been looking at info on different batteries. I looked at Nickel/Iron because of their known long life. One change mention from original Edison design is adding a little Lithium oxide or dioxide ( forget exactly) to the electrolyte To extend the life of the Iron electrode. There was also something about making plates (instead of just using sheets of iron) using iron powder with carbon (for conductivity) and something else which I forget that reduced the production of hydrogen.