Experimental Performance Comparison of a Single Cell and Multi-Cell Stack of High Temperature PEM Fuel Cell Prototype

In this study, we experimentally studied our newly designed and built single cell and multi-cell high temperature (140°C∼180°C) polymer electrolyte membrane (HTPEM) fuel cell stack prototype at different operating conditions to investigate the effects of operating temperature, pressure and CO concentration on the cell performance. In particular, the effects of these parameters on the current-voltage characteristics of the fuel cell stack are investigated extensively. Experimental results obtained from both the single cell and multi-cell stack with high temperature PBI-based membrane show that the high CO tolerance at high operating temperature of HTPEM fuel cell stack makes it possible to feed the reformate gas directly from the reformer without further CO removal. In order to develop design parameters for fuel reformer, experimental data of this type would be very useful. The experimental results revealed the fact that a fuel reformer is a consumer of heat and water, and the HTPEM fuel cell stacks are a producer of heat and water. Therefore, the integration of the fuel cell stack and the reformer is expected to improve the entire system’s performance and efficiency. The results obtained from this study showed significant variations in current-voltage characteristics of HTPEM fuel cell stack at different temperatures with different CO poisoning rates. The results are promising to understand the overall system performance development strategy of HTPEM fuel cell in terms of current-voltage characteristics while fed with on-site reformate with different CO ratios in the anode fuel stream.