Proposal for a master internship 2016

Mission proposée

Experimental study of the influence of internal mechanical compression
on the performance of a single-cell fuel cell

Context:

Fuel cell should play a major role in the future energy mix. Among the different fuel cell technologies, the Proton Exchange Membrane Fuel Cell (PEMFC) has already proven a strong potential for stationary and transportation applications. The PEMC strengths are its low operating temperature, the solid state of its electrolyte and its compactness. Nevertheless, before mass production and commercialization, one of the technological issues concerning the PEMFC is the optimization of the overall energy efficiency under the real operating constraints. This analysis is difficult because of the number of components and their heterogeneity: bipolar plates (BPs), gas diffusion layers (GDLs), catalytic layers, electrolytic membrane, gaskets, mechanical clamping…

Project abstract:

Recent researches have identified the mechanical properties of the internal components (in particular, GDLs) as key parameters concerning the final performances of fuel cell systems. The compression modulus of these components, the stability of their mechanical properties with respect to temperature and humidity and their ability to interact with water have an impact on the electrical contact resistances in the stack and, by consequence, on the overall performances of the electric generator. Reducing the losses by contact resistance is an objective necessary to the optimization of fuel cells in operation. Under particular operating conditions, the losses by contact resistance can reach up to 60 % of the total losses in the stack.

During this internship, we aim at testing and exploiting an experimental device that measures the effects of mechanical compressions applied to a single-cell fuel cell in operation. The fuel cell performances are electrically monitored while the mechanical compression is applied by a piston and completely controlled by a dedicated electronics and a specific software. The testing system allows an autonomous operation of the fuel cell (only the gas supply is necessary to operate the testing system). This equipment will help us to define the physical relations between the mechanical compression applied to the stack and the electrical performances in several operating conditions (temperature, humidity, load current …).

Research partnerships:

Three research partners (UTBM, IFSTTAR and Fraunhofer ISE) and two structures hosted by the fuel cell test platform of Belfort - France (FCellSys and FCLAB Research) are involved in the project consortium. This consortium provides an excellent coverage both in terms of scientific and technical competencies, as well as complementarity.

UTBM and FCellSys, center of technological resources around hydrogen and fuel cells, bring skills in experimental characterization (mechanical, thermal and electrical) and in modeling of the fuel cell components as GDLs and membranes. IFSTTAR and FC Lab Research have an expertise in the test and characterization of fuel cell systems: design and achievement of experimental testing, monitoring and control of fuel cells in real use conditions.

With a staff of about 1300, the Fraunhofer Institute for Solar Energy Systems ISE conducts research and develops technology for an environmentally friendly energy supply. The work focusses not only on solar energy conversion but also flexible storage, intelligent distribution and efficient utilization of energy. The institute pursues a practical approach to bring new products and processes to commercially marketable maturity with and for industrial partners.