The influence of current collection on the performance of tubular anode-supported SOFC cells

A mathematical model is developed and used to investigate the effects of axially distributed current collection on the performance of an anode-supported tubular solid oxide fuel cell (SOFC). The physical model considers coupled fluid and thermal transport within the tube, reactive porous-media flow within the electrodes, electrochemical charge-transfer, thermal transport within the MEA structure, and an electric circuit to represent the current-collection system. Four examples are used to illustrate the model and evaluate current-collection strategies. All the examples consider a particular Ni–YSZ || YSZ || LSM–YSZ tube, but with different current collection. The inlet fuel stream is a syngas mixture that results from steam reforming of dodecane. Results show that current collection can strongly affect local performance (i.e., composition, temperature, and current density profiles) along the length of the tube as well as overall performance (i.e., efficiency and utilization).