부산대학교 도서관

Polymer electrolyte fuel cells (PEFCs) offer the possibility of cleaner and more sustainable forms of energy, which is very important due to the global increase in energy demand and consumption. However, for PEFC stacks to become commercially viable, they must compete with and even surpass current technologies in aspects such as cost, performance, durability and portability. One of the major technical hurdles hindering the widespread implementation of PEFCs is the ability to manufacture long-life portable stacks in a cost-effective manner. Planar PEFCs constructed using printed circuit board (PCB) flow field plates (FFP) are a promising solution to these challenges as the cell configuration can be arranged to reduce the size of the stack and consequent materials needed, thereby minimising cost. This thesis aims to develop open- and closed- cathode planar PEFCs using PCB FFPs. In-situ and ex-situ diagnostic techniques are also applied to understand its internal workings in order to improve performance thereby developing a more efficient system. The result indicates that there is great potential in the use of planar fuel cells as power sources especially for low power applications (10 W). A five cell stack was developed for the closed system and it achieved a gravimetric power density of 263 W kg-1. Investigation into the open cathode fuel cell indicates that an optimum opening ratio is ~ 60% and the ideal operating point is between 200 mA cm-2 and 250 mA cm-2 as this represents an ideal trade-off between power and efficiency. Open-cathode fuel cell constructed using PCB FFPs should also be operated in a flat-upwards orientation to reduce the effect of water accumulation.