Adding turbulence to airflow traveling through channels in a fuel cell stack markedly improves the efficiency of A simple plastic grid can increase the efficiency of an air-cooled fuel cell stack by over 30 percent. Source: Aalborg Universitythe device. Researchers from Aalborg University, Denmark, explained that turbulence has a major effect on the heat transfer that occurs in fuel cells. Transferring the waste heat generated during fuel cell operation via turbulence prevents overheating and boosts device performance.

The researchers enhanced the efficiency of an air-cooled fuel cell stack by 33.5 percent through use of a small 16 x 16 cm plastic grid.

Heat increases in a fuel cell stack as power is extracted. Heat transfer is relatively poor with laminar flow, and this limits how much power can be extracted from the system. Adding turbulence not only ensures effective heat transfer to the air but also raises fuel cell efficiency.

The air-cooled fuel cells are currently being used in material handling with forklifts, as emergency power plants for IT and the telecom industry and for smaller drones. Fuel cells typically last five to six years, depending on how they have been operated, but service life can be extended by adding the plastic grid to a fuel cell stack for thermal management.