Scaling of Automotive Fuel Cells in Terms of Operating Indicators

The search for alternatives to fossil fuels has led to hydrogen becoming an important factor in the powering means of transportation. Its most effective application is in fuel cells. A single fuel cell is not a sufficient source of power, which is why a stack of fuel cells is the more common solution. Fuel cells are tested using single units, as this allows all cell parameters (the current density, flow rates and efficiency) to be evaluated. Therefore, the scalability of fuel cells is an essential factor. This paper analyses the scalability of fuel cells with a power of approximately 100 kW and 1.2 kW. Road tests of the fuel cells were compared with stationary tests, which allowed the load to be reproduced and scaled. This provided a representation of the scaled current and the scalable power of the fuel cell. The research provided voltage–current characteristics of fuel cell stacks and their individual equivalents. It was concluded that regardless of the power scaling or current values, the characteristics obtain similar patterns. A very important element of the research is the awareness of the properties of these cells (the number of cells and active charge exchange area) in order to compare the unit characteristics of fuel cells.