Getting rid of fuel cell / flow battery membrane

[dgjxqz]

I am aware of laminar flow but would like to look for some other ways.
Is it possible to block ions from flowing in the "wrong" direction by applying a magnetic field to the electrolyte and let neutral molecules pass through?

 

[dgjxqz]

As an example (which probably won't work but other combinations may), a magnetic field is setup to allow positively charged ions to flow from negative half cell to positive half cell but not the other way round.
In the negative half cell, H₂PO₂^- is oxidized to HPO₃^2-, both ions are negatively charged thus won't flow to the positive half cell.
In the positive half cell, VO₂⁺ is reduced to VO²⁺, both ions are positively charged thus won't flow to negative half cell.

 

[biofuel_chemist]

You are leaving out the proton and hydroxide redox half reactions in your example, which complete the electrical circuit and generate movement of (at minimum) water between the electrodes. I don't think your proposed membrane-less scheme will work because the magnetic field strength is much weaker than other motive forces acting on the ions in solution.

 

[dgjxqz]

Yeah, looks like one reaction is acidic while the other is basic. Perhaps S₂^2-/S₄^2-,Fe³⁺/Fe²⁺ is a better example?
How do you calculate other forces (diffusion?)?

 

[russ_watters]

Can you explain what would be the point of this?

 

[dgjxqz]

Ion exchange membrane is often a bottleneck in flow batteries, a membraneless system can reduce complexity and improve efficiency.