Study on a new structure of the separator plate assembly for molten carbonate fuel cell (MCFC) stacks

A new structure of separator plate assembly (SPA), which consisted of a separator plate, flow field plates, perforated plates, frame plates and seal gaskets, was developed for a molten carbonate fuel cell (MCFC) in this study. In this structure, the separator plate, flow field plates and perforated plates were hard-contacted (directly contacted each other); meanwhile the frame plates and the separator plates were bound with the inorganic seal gaskets. SPA and electrodes could be combined together to form a unit of electrode-SPA. The new structure SPA promoted the smooth volatilizing and complete burning of the organic compounds in the matrix. It was effective and reliable to press the stack with a suitable stacking pressure. It was facile and simple to assemble a stack by using electrode-SPA. With the electrode-SPAs, two MCFC stacks were assembled in co-flow and counter-flow, respectively. The performance of Stack B in counter-flow was higher than that of Stack A in co-flow at the same current density. The more uniform temperature distribution and current density distribution in Stack B were responsible for its higher performance.