Experimental design and assessment of a novel mixed-cooling proton exchange membrane fuel cells stack for enhanced power generation and thermal management

In this study, a novel mixed-cooling proton exchange membrane fuel cells (PEMFCs) stack is proposed and fabricated, which has been specially tailored with an efficient mixed cooling pathway. Compared with conventional air-cooled stacks and previous-generation split-cooling stacks equipped with micro heat pipe arrays, the mixed-cooling stack achieves higher load capacity, improved power generation performance, and superior thermal performance. In addition, the mixed-cooling stack is configured with fewer fans, resulting in lower additional power consumption and a more uniform voltage distribution. The experimental results indicate that the load capacity of the mixed-cooling stack is 14.3 % higher than that of the split-cooling stack and shows a 71.4 % increase compared to the ordinary air-cooled PEMFC stack of the same specification. At the same current, the net power output of the mixed-cooling stack is 65.9 W higher than that of the split-cooling stack. When operating at 30 A, the maximum voltage difference for a single cell within the mixed-cooling stack is only 0.100 V, and the voltage uniformity index is 70.2 % lower than that of the split-cooling stack. Furthermore, the temperature uniform index of the mixed-cooling stack is superior to that of the split-cooling stack under identical current conditions.