Solid Oxide Fuel Cells (SOFC) R&D began in 1987 in the JOULE programme, with the development of small cells. This research has now reached a stage where kW size SOFC systems are constructed on different concepts. This project involves the flat-plate SOFC concept with multiple array cells and metallic bipolar plates. It will include : - The development of stack technology for large area metallic bipolar plates and adequate joining technique.
- Improvement in the lifetime of SOFC components and testing under realistic conditions (single small stack tests with 3 cells in series). Stacks up to a power of 1 kW will be assembled and tested.
- The testing and optimization of mixed ionic/electronic cathode materials, which will be used as supporting substrates for thin electrolyte layers and anode top-layers.
Till now the partners have increased the current densities of single cells to about 1.000 mA/cm2 and have demonstrated the technical feasibility of the Siemens multiple cell array design by testing several stacks, up to 10 layers connected in series, each containing 4 cells in parallel (100 W stack).
The first part of the project aims at the development of 20 kW SOFC technology. This includes assembly and testing of a short stack in the first year and a 1 kW stack in the second year. The characteristics of the 20 kW technology are metallic bipolar plates with enlarged area and adapted thermal expansion behaviour with respect to the electrolyte material. The metallic bipolar plates will be connected to the electrodes by metallic and ceramic functional layers, respectively (Siemens AG, Erlangen).
The joining materials will be improved and the joining techniques will be adapted to the upscaled area. The joining materials will be available for the partners. (GEC Alsthom, Stafford) The lifetime of SOFC components will be improved and characterized under realistic testing conditions. Single cell tests using enlarged cells and 3 cell stack tests will be carried out (ECN, Petten).
The second part is directed to the development of new mixed
ionic/electronic cathode materials for low temperature operation at about 800°C. To reduce the ohmic resistivity of the state of the art electrolyte material, thin layers of electrolyte material will be deposited onto cathode substrates. To complete the cells, anodes will also be deposited as second thin layers (Imperial College, London).
Funding SchemeCSC - Cost-sharing contracts
ST17 4LN Stafford
SW7 2BP London