This circulated without any leaks, even lacking one of the endplates. [image: 1757751389933-acf0d9aa-832c-4c50-9b03-c659d088e03a-image.png] I will try doing a 3 cell stack, removing one of the other birch wood end plates.

My pumps didn't have them, only the ones built into the pump. I saw that on some of your pictures, you have additional fittings between the different elements, I guess to make it easier to connect and disconnect the cell. In the end, it might make more sense to just shrink the barbs on the flowframe and/or tank a bit so the tubing comes off mor easily.

@sepi Thanks for trying this. I understand what you mean, I had similar issues when I tried to do this before. The main issue is that the fit is quite tight, so depending on the resolution of both the sleeve and the hole on the endplate, you can have too low of a tolerance for it to work. The easiest fix is probably to increase the size of the holes on the endplate around 0.25mm, so that this works regardless of the printer. We will make the modification on the official endplate exported files so that this approach works more easily.

@danielfp248 ah, that makes sense as a last resort measure but would it not be nice to not lose charge? Well it all depends on how easiy it is to counteract by setting a different flow for the different electrolytes.

@sepi @danielfp248 Thanks for the quick and thorough answers! You should add those points to the docs unless you feel that this might potentially create legal trouble. I think we can add these as reasonable guidelines, we will include clarification that waste disposal should always be consulted with local regulations though. About the PPE, I was wearing nitrile gloves, cotton work cloths and plastic safety glasses (not closed though). I felt reasonably safe That seems adequate, especially if adequate ventilation is also in place. The quantities are small, so hopefully this also reduces the risk. About the copper carbonate for precipitation, would that be the natural one or basic one? Since I'm curious and want to bring my chemistry skills up to date: how do you know that this will cause precipitation? Is this compound used frequently for precipitation? Is this about chemical potential of copper iodide (s) and zinc carbonate (s) being lower than the sum of their respective ions (aq) in solution? This is because Zn carbonate and Cu iodide are insoluble so a double displacement reaction occurs and both fall out of solution. There is an additional complication in that Cu+2 does oxidize I- to elemental I2, so you will also have some solid iodine formation. What precipitates is actually Cu(I) iodide. You can add some Na thiosulfate if you want to make sure all iodine precipitates as copper (I) iodide.

@Vorg We will slowly get there but no, right now we don't have any kWh capacity battery. As I mentioned, it will be several years before we get there. The fun is to walk this path and make everything open source on the way.

@sepi Hi, if you do the selling of the tube, I would order 2 (two) meters.

@danielfp248 sorry, my question was not well formulated. I meant a potential between the electrolytes inside the cell independently the possibility of measuring them using an electrode. Or to formulate it differently, if you cut through the cell (lile you cut a sandwich) and plotted the electrical potential between the electrodes, how would it look like?

@czahl I am a huge fan of trying this, especially for the larger format where setups are likely to be more permanent. As kirk mentioned we have never actually tried it, so please let us know if you do!

@muntasirms Absolutely! A bunch of other great documentation on here, wanted to try to my part. I have a colleague who uses HIPS exclusively in strong alkaline systems. Significantly easier to print than PP from my limited experience. It's not pure polystyrene (which is great for alkaline), but the additive(s) don't seem to affect their tolerance too much. I'll keep you posted on compatibility as I test these systems! Not sure how long the parts will last yet.

@kirk @sepi I think Bert's models are free to download off his site, but if you wanted to read the paper, I'm happy to email them to you or you can reach out to him for a copy.

On it, thanks @sepi !

@gus nice! That's the spirit! Keep us up to date please. I'm almost done building the thing. Printing the PP parts right now then I just need to wait for the pumps, tubing and potentiostat to arrive.

Ah, in the FAQ ... Yes, was thinking wrong from other and not so good sources.

@sepi Unless you are very experienced soldering small components I would suggest not doing this. Some of the expensive components are tiny and easy to damage, either by overheating or by soldering multiple legs together and causing shorts. I tried soldering my own mystat 3 times (without success) before I got my first working one from pcbway. I am however, not good at all at soldering.

My latest quote is 315$ with assembly included by PCBWay. That's expensive but not prohibitive. Thanks for the input!