Segmentation of MEA by LASER Ablation

摘要

In a flat design several serial connected single cells are arranged side by side in a plane. Sealing problems can be reduced by using one single MEA for all cells. This MEA must consist of segments of catalyst coated area. In order to avoid short circuits between serial interconnected cells their catalyst segments have to be electrically insulated. The distance between the segments has to be minimised to use the MEA area most efficiently. By the use of conventional coating technology the distances between electrode areas are in the range of some millimetres. With LASER ablation the distance between the segments can be reduced to less than 200 μm. Results of removing the catalyst by LASER ablation are analysed by SEM and light microscopy. The electrical resistance between segmented areas are determined with 4-point probe impedance measurements. The influence of the segmentation on the cell performance is characterised in a planar serial connected test cell.