Modelling and DC-polarisation of a three dimensional electrode/electrolyteinterface

A finite element model (FEM) was developed which is able to calculate and p redict the electrical performance of a solid oxide fuel cell (SOFC) with a three dimensional interface between cathode and electrolyte. An enlargement of the electrochemical active surface leads to a significant increase of t he electrical performance of a SOFC. Various three dimensional electrolyte/ electrode interfaces have been realized by first screen printing of individ ual 10YSZ particles onto a flat and dense 8YSZ substrate. Surface enlargeme nts between 10 and 50% have been realised and investigated. Second, a scree n printed cathode (LSM) layer was applied as a current collector and gas di stribution layer. In order to develop a FEM-model for this type of cathode/ electrolyte interface, several electrical properties of cathode (LSM) and e lectrolyte (8YSZ) were examined. Further on, measurements of symmetrical ce lls (LSM/8YSZ/LSM) to evaluate the electrode resistance R-0 were carried ou t for different symmetrical cells. Taking into account the enlargement of t he interface surface, electrical conductivity and electrode resistance R-0, the entire DC polarisation-resistance R-pol could be calculated by FEM. (C ) 2001 Elsevier Science Ltd. All rights reserved.