The EVOLVE Project is a collaborative European (SEVENTH FRAMEWORK PROGRAMME THEME SP1-JTI-FCH.2011.3.1) project funded by the Fuel Cell and Hydrogen Joint Undertaking (FCH JU) where 8 partners worked together at the development, up scaling and demonstration of new SOFC architecture for stationary and mobile application. This architecture, based on a composite anode substrate tolerant towards redox cycles aims at combining benefits of both existing anode and metal supported cell architecture, and limit the issue of carbon coking and sulphur poisoning thanks to improved anode materials.
Focus of the Project
Evolve focuses on an innovative concept for SOFC, particularly for the anode compartment, incorporating advanced materials with an approach in which each material performs only one function and enables cell operation at reduced temperature of 750°C. This concept is expected to enhance the durability and reliability of SOFC while exhibiting performance level equivalent to main-stream anode-supported cells.
Milestones to be Reached
- Power densities of cell at 0.7 V at 750°C above 550 mW/cm2 with hydrogen as fuel gas,
- Degradation in cell voltage 0.25%, 0.6% and 1.5% per kh during operation with hydrogen as fuel, syngas and syngas with at least 80 ppm of H2S respectively.
- Tolerance to withstand at least 50 thermal and redox cycles with less than 5% degradation in cell voltage.
- Demonstrate up-scalability of cells having the performance level defined in objectives 1-3.
- Integration of cells in 250 W stacks and its operation.
- Using realistic model cost analysis, establishing processing sequences and practices for the cell components to attain optimal cost-to-quality ratio.
Achievement of Objectives
The cell will be supported on a novel composite anode-current-collector made of aluminia-forming-alloy-foam impregnated with conductive ceramics. An anode layer of LSCM-CGO and YSZ electrolyte will be produced on top of the support followed by sintering. CGO and CGO-LSCF will be deposited on top of electrolyte. Catalysts will be then infiltrated in electrodes. The development will be based on correlating material, processing, microstructure and electrochemical performance and optimizing cell in term of performance and service life by combining experimental work with model for 3D microstructure, electrochemical kinetics and sintering. Based on these optimized processing protocols, up-scaled cell will be stacked.
A fuel cell is an electrochemical energy conversion device that converts directly the chemical energy of the combustion of hydrogen with oxygen into electrocity. The core component of a fuel cell is made of three parts: an electrolyte, an anode, and a cathode.
For a solid oxide fuel cell, the electrolyte is a solid ceramic material. The anode and cathode are made from special compounds that coat the electrolyte. Unlike other types of fuel cells, no precious metals, corrosive acids, or molten materials are required. Two electrochemical processes allow the convertion of fuel and air into electricity without combustion.
At high temperature, warmed air enters the cathode side of the solid oxide fuel cellwhile the fuel feeds the anode side. The oxygen contained at the cathode side is reduced into oxygen ions which, after diffusion through the electrolyte membrane are recombined at the anode side with the fuel molecules through an oxidation process. The whole process generates electricity heat, while water is produced as a waste from the reaction. When the fuel gas contains some carbon species, carbon dioxide is also formed as a product of the electrochemical process. As long as there is fuel, air, and heat, the process continues producing clean, reliable, affordable energy.