Porous materials are of special interest for the development of electro-devices such as bio-batteries, bio-actuators and bio-sensors, in particular for miniaturization purposes. Because of their potentially large specific area, these materials allow high current density production that can be several orders of magnitude larger than simple flat electrodes of comparable volume. Nevertheless, these materials have always been designed so far on an empirical basis regarding the thickness of the material and its pore size and organization. These parameters have a crucial impact on the competition between mass transfer, enzymatic turnover and heterogeneous electron transfer rate. A way to progress in their optimization is to make use of modelling, in order to decipher the relationship between the microstructure and the macroscopic properties of the electrode. The presentation will show how this modelling approach through the scales can be performed in conjunction with material reconstruction based on image analysis and electroanalytical tests carried out on synthetized porous materials. Several different electro-chemical situations will be illustrated and an optimization procedure for the electrode macroscale dimensions will be reported. The overall procedure opens the way towards a rational recursive way of an optimal design for efficiency improvement of these devices.