Analytical Study, 1-D Optimization Modeling, and Testing of Electrode Supported Solid Oxide Electrolysis Cells

The need for an infrastructure to provide hydrogen as a next generation energy carrier is ever increasing. High temperature solid oxide electrolysis cells (SOECs) have been proven to be a viable technology in the production of hydrogen [1]. With the increasing use of SOECs in various operating environments it is important to be able to specify the best SOEC for any given situation. We have developed a straightforward model to estimate cell performance in a timely and inexpensive manner. Composite electrode planer type SOEC models have been developed previously. It is a common assumption that all electrochemical reactions in these cells occur at the interface of the electrolyte and the electrode [2]. It has been shown by S. Gewies et al. [3] that the reactions occurring throughout a Ni/YSZ cermet electrode occur in a nonlinear fashion. Our one dimensional model has been developed to optimize SOECs with composite electrodes. This model takes into account ohmic, activation, and concentration polarizations. The electrochemical reaction that occurs within the electrode functional layers has been accounted for in the calculation of the concentration polarization. This is believed to give a more realistic view of the mass transfer that occurs in SOECs with composite electrodes via a simple and straightforward 1-D model.