High-temperature proton exchange membrane fuel cell – Approaches to better performances

The methods to improve the performances of a High-Temperature Proton Exchange Membrane Fuel Cell (HT-PEMFC) have been studied. Two approaches were tested: the catalyst layer (CL) combination and external temperature control. The CL structures, properties, binder, and platinum/carbon (Pt/C) concentration were chosen as perimeters to find the best CL combination. The lowest weight percentage of Pt/C, provides the thickest CL with a smaller size and uniform distribution of Pt catalyst. Consequently, the electrochemical reaction can easily happen. The Polytetrafluoroethylene (PTFE) binder provides a higher gas permeability, resulting in more gases diffusing to the working area. The maximum current density of 0.62 A/cm2 and the highest power density of 190.15 mW/cm2 at 0.3067 V was reached, and the best combination of CL is 10 wt% Pt/C with PTFE binder. Temperature control of HT-PEMFC stack with heat pipe (HP) is also successfully proved. Both heating and cooling by HP provide a more uniform temperature distribution in the working area and a low-temperature gradient across the stack than the commonly used technique for controlling fuel cell temperature.