Silver wire seal design for planar solid oxide fuel cell stack

A method for sealing solid oxide fuel cells with silver wire gaskets was developed and tested. The 1.6 mm diameter gaskets were fitted into machined channels, 1.5 mm deep in the interconnect plates. The channels were machined into 430 stainless steel plate along the edge of both surfaces and around alternate gas inlets. The interconnect plates were 6.35 mm thick, 152.4 mm long and 76.2 mm wide. A one-cell-stack was assembled for pressure testing with a stainless steel sheet in place of the ceramic membrane. The gas connections were brazed to the stack with a nickel–chromium brazing alloy. The apparatus was bolted together and tested for gas leakage at 137.8 kPa between room temperature and 500 °C. At room temperature, the measured leak rate was 5.14 kPa min−1. With the stack heated to 500 °C, the leak rate decreased to 75.8 Pa min−1.