Sciencemadness Discussion Board

Solubility of Vanadium compounds in sulfuric acid

ReaktionChamber - 10-1-2018 at 22:12

Hey guys,

so i am currently working on a Vanadium redox flow cell, and I already got sponser for the membrane and so on. My problem is that I have to order the chems, and I don't really know how much and which to order.

So looked up in the internet and it says to use Vanadium Oxide Sulfate and vanadium(III)sulfate.
First problem, Vanadium(III)Sulfate May be not available. Any ideas for an exchange chem?
And my big problem is the solubility of these compunds in sulfuric acid. In the internet it says to use battery acid (38% H2SO4) and dissolve the 2 salts into it. Has any1 information on how much I need ?? I only want to build one stack so...

Ty, for further answers
Kind regards reaktionchamber

NEMO-Chemistry - 12-1-2018 at 19:52

Where are you? I have way too much pentoxide

NEMO-Chemistry - 12-1-2018 at 19:56

https://en.wikipedia.org/wiki/Vanadium(III)_oxide

halogen - 13-1-2018 at 17:35

Now I don't want to be like Socrates here, and, by asking questions, reveal what may seem to be ignorance... so, in any case, if you have obtained by accident a soluble vanadium salt that is the wrong one, you are likely to be able to convert it relatively simply to a better one.

NEMO-Chemistry - 14-1-2018 at 02:59

Maybe I should change my font and wear my glasses more :D

unionised - 14-1-2018 at 03:22

You can make the vanadium(III) sulphate by charging the battery.

I suggest checking the patent literature for hints at concentrations.

ReaktionChamber - 7-5-2018 at 07:39

So I found online that the electrolytes in the VRFB both a made by dissolving vanadium pentoxide in sulfuric acid. 2V2O5 + 4H2SO4 → 4VOSO4 + 4H2O + O2, now I know how VO2+ is formed but how is V2+/V3+ formed???

j_sum1 - 7-5-2018 at 12:30

Keep us posted on this project. Flow batteries are a fascinating idea and something that I would love to see become more available.

stamasd - 24-5-2018 at 18:13

The main problem with vanadium flow batteries is that due to the complexity involved they're not cost-effective unless they're very large. You can't just make them by rolling together 2 electrodes and an electrolyte-soaked membrane. It's unlikely that we'll use them in cell phones any time soon. If you could work toward that goal though, you have my full support. :)