The state of the art anode material used in Solid Oxide Fuel Cells is the Ni/YSZ ceramic-metal (cermet) composite (where YSZ = Y2O3/ZrO2) which has several difficulties in use. The anode is prepared as NiO/YSZ, and must be reduced to Ni/YSZ to work: this entails a large volumetric shrinkage, which can cause the cells to crack. Ni is a good catalyst for cracking hydrocarbon fuels, but tends to produce solid carbon, which then blocks the electrode, lowering performance and effective working life. The metallic Ni phase is also mobile and tends to sinter over time, again lowering performance.
Our technology overcomes these problems while achieving a comparable electrochemical performance, electrical and catalytic properties (significantly better when used with methane fuel). The new perovskite anode shows better tolerance to hydrocarbon fuels, without depositing carbon on the electrode. The perovskite anode can withstand more repeated cycling than a Ni/YSZ anode.
- As effective as existing materials but without the problems such as cell cracking and reduced effective working life.
- Redox stable - no cracking on cycling.Highly tolerant of hydrocarbon fuels.
- Resistant to carbon deposition.No need for initial cell reduction.
- The perovskite anode can be used in any Solid Oxide Fuel Cell (SOFC) instead of Ni/YSZ, where redox stability or hydrocarbon use is needed. This covers most applications of SOFCs.
- The University would welcome enquiries from commercial parties interested in developing commercial applications of fuel cells and fuel cell materials.
The University of St Andrews has granted patents in Japan, USA, Canada, China, Australia and Europe (GB, France, Denmark, Switzerland, Italy, Spain, Austria and Germany) and continues to perform R&D in advanced materials for fuel cells. The University is looking for a licensee to the patents and knowhow or a commercial collaborator to take it to market. Patent Numbers: PCT/GB2003/003344, Granted patents: US 7,504,172 , Europe 1532710. Additional information can be made available under a confidentiality agreement.