This study provides a step-by-step, up-to-date fuel cell fundamentals, thermodynamic and
electrochemical principles, and system evaluation factors via a case study of a 10-kW alkaline fuel cell designed to operate in space applications. The system also produces 100 kg of pure water and 5.5 kW of heat. The system is modelled using MATLAB and ANSYS Fluent.
Then, the model is verified with theoretical and experimental results from the literature.
A parametric study of various design and operating parameters, and material selection is
carried out to optimize the overall performance. A net output voltage of 0.8 V is obtained at
150 mAcm-2 current density, which yields an overall efficiency of 75%. The results indicate
that increasing the electrolyte thickness or operating temperature results in a lower net
voltage output. Additionally, improving the performance of a fuel cell through the bipolar
plate can be achieved by understanding the contribution of different parameters towards
minimizing the pressure drop across the bipolar plate. It is found that implementing an
optimized selection of fluid flow rate, channel width, channel depth, number of channels and
current density minimize the pressure drop throughout the bipolar plate. Relative humidity
has a significant effect on the pressure drop. Results indicate that increasing the relative
humidity consequentially rises the pressure drop. Finally, the CFD simulation illustrates that
the end-zones in the bipolar plate accumulates fluid due to the nature of stagnation at those
locations. Thus, total pressure at those locations is the highest. One of the major contributions
here is studying the effect of KOH concentration on the performance of the AFC at different
operating temperatures. In addition, a wide range of design and operating parameters were
analysed to understand their effect on the overall performance of the fuel cell.