[A CFD free user]

Hello Folks
I want to define two electric and protonic potentials inside a fuel cell using UDS. Here's the problem: when I define electric field, then it's required to define UDS diffusion coefficient which is in fact, electrical conductivity and has a dimension just (1/ohm.m) and it's different from UDS diffusivity coefficient exist in material panel which is (kg/m.s). How can handle this problem? Furthermore, in material panel there are also other parameters such as density or viscosity and etc. what should I do with them for UDS? Should I actually use material panel for this purpose?
Please give me some advice.
Thank you in advance.