About conductive electrodes of piezoceramics layers

Hello everyone,

I am working on a piezoelectric energy harvester(substructure and a piezoceramic layer). I am applying a point force on the substructure and measuring the voltage from the surface of the piezoceramic to obtain voltage FRF (voltage/point force).

I want my model to account for the conductive electrodes bracketing the piezoceramic layer so that I can obtain uniform potential distribution throughout the surface of the piezoceramic. However, I couldnt find the appropriate boundary condition for this purpose.

I appreciate any help,
Bugra Bayik.