Fuel cells are basically considered as a green technology addressing the high demand for a sustainable and climate friendly mobility. Without the use of fossil energy, fuel cells provide electrical energy by the electrochemical reaction of oxygen (O₂) of the environmental air with hydrogen (H₂) of the storage tank in the vehicle yielding pure water as the final product. However, since environmental air comprises a wide variety of different gases, some of them negatively affecting the functional performance and the life time of fuel cell stacks, the incoming air must be selectively filtered before entering the fuel cell stack. Basically, air filtration makes use of adsorbents that capture target gases by physisorption and chemisorption, both depending on environmental influences, like relative humidity (i.e. water molecules), air temperature and gas concentrations. In terms of cathode air filtration, the interplay between temperature, water molecules and gases and their interaction with the adsorbent is poorly understood under long term conditions, but mandatory for developing tailored filtration materials. Especially, gaseous air pollutants, such as ammonia (NH₃) and sulfur dioxide (SO₂), were shown in the past to have a negative impact on the functional integrity and on the life time of fuel cell stacks.
In this study, the gas concentrations of ammonia and of sulfur dioxide as well as the environmental air temperature and relative humidity should be continuously monitored for a long period of time, thereby receiving a sophisticated image of environmental conditions. Therefore, dedicated sensors will be installed into a container that is located in a highly frequented street in Ludwigsburg, Germany. Furthermore, besides detection of environmental conditions, a gas adsorption filter, intended for protection of fuel cell stacks, will be additionally mounted into the same container and the ammonia and sulfur dioxide concentrations after the gas filtration step, i.e. on the downstream side of the filter will be detected in situ as well. The results of this approach will enable...