GREEN HYDROGEN LABORATORY

In the era of rapid deployment of conventional sources of fuel, with much emphasis given on renewable energy sources, fuel cells have found themselves a good fit between energy and power delivered. Polymer electrolyte membrane fuel cells (PEMFCs), in particular, are being explored extensively in unmanned aerial applications. Cylindrical PEMFCs are found to be better candidates for such applications owing to their multifold gravimetric and volumetric power densities compared to planar structures.

Here, we are involved in investigating the fabrication as well as sizing issues with the cylindrical/tubular fuel cells. Such fuel cells have tremendous potential in small to medium power applications (<500 W). The structural modifications will surely help these types of fuel cells gain more visibility in industries as well as commercial market.

Renewable energy sources have been able to satisfy the ever growing demand of energy throughout the world, however, their intermittency of energy production have put enormous load on the grid. this load is sometimes too heavy for the grid to hold leading to its failure. Unitized regenerative fuel cells (URFCs), therefore, are being investigated as  possible solution to standalone systems, in particular. 

URFCs smartly couple the fuel cell and electrolysis characteristics and therefore work both as load as well as source. The surplus energy available from primary renewable sources (e.g. PV modules) may be supplied to URFC which would generate hydrogen and oxygen in electrolysis mode of operation. These gases, once stored locally, can further be used to supplied to URFC running in fuel cell mode thereby powering the load when primary source fails.

The research focus of our laboratory has been primarily on resolving the durability issues with the technology as well as optimize the cell structurally such that the interfacial contact resistance is kept minimum.

Fuel cells, primarily convert chemical energy of fuel directly into electrical energy leaving water as only its biproduct. such conversion of energy is highly effective/efficient when the size of cell/system is small (electrode area<100 cm2). This is primarily due to the lesser chaos in the system leading to better distribution of gases, effective management of heat and water produced, better contact between the interface of electrode and the current collector and so on! The better interfacial contact helps electrons to pass to/from one cell component to the other thereby minimizing the contact resistance of the cell. 

With increase in the size of fuel cell (electrode area) increases the complexity of system in terms of gas distribution and its availability at the reaction sites, contact pressure and its distribution across the interface etc. All such factors damp the fuel cell performance to a great extent. Hence, it becomes very important for scaled up fuel cells to optimize and select the very parameters such as clamping pressure, gas pressure, gasket material and thickness etc. such that contact pressure at the electrode and current collector is well distributed for minimum resistance.

One of the research focuses of our research group has been the identification of scale up issues in fuel cells and efforts are being put up in resolving the same.