Proton exchange membrane fuel cells are becoming more relevant especially in the automotive sector given the new transition underway towards electric. In the introduction there is a brief explanation of the state of art of fuel cell sector, the principal automotive solutions available today, how polarization curve is obtained and the importance of catalyst deposition to improve cell performance. This is followed by an explanation of the COMSOL model used to execute the cell performance simulations with all equations that govern it. After this first explanation, I provide some ionomer ink preparations in the laboratory of Politecnico, analysing how temperature can influence the mixing procedure.