Jülich--Jülich scientists have set a new world record: Their fuel cell stack with high-temperature fuel cell is running now for over 8 years or 70,000 hours. That's longer than any other fuel cell with ceramic cells. Such solid oxide fuel cells are suitable as ideal and due to their high effeciency and could supply households and small businesses, large vehicles like trucks, trains and ships with energy due to their high efficiency. Research State Secretary Thomas Rachel congratulated the Jülich researchers to reach the new record.
Thomas Rachel said, Parliamentary Secretary, Federal Ministry of Education and Research."The fuel cell world record in the research stage shows that fuel cells are a highly efficient and environmentally friendly electricity and heat source,and can help to compensate for fluctuations in renewable energies and thus make an important component to the success of the energy transition in Germany."
High temperature fuel cells deliver the highest electrical efficiencies of up to 60 percent, recapturing the waste heat can be exploited even more. The long-term test was launched on 6 August 2007 and is intended to demonstrate the durability of the solid oxide fuel cell developed at Jülich. 5 to 10 years or converted 40,000 to 80,000 hours, they have to run, so that the effort is worthwhile economically. In the field of electricity and hot water supply in the home the high-temperature fuel cell technology is already available for use in vehicles, experts anticipate even with a development time of about five years.
"The operating temperature of 700 degrees Celsius places enormous demands on the materials used. With the record we can now demonstrate for the first time that we have developed materials ready for application in combination and are in working order over such a long period, which initially held hardly anyone for possible had, "said Harald Bolt, member of the Executive Board of the Forschungszentrum Jülich.
The two-cell stack is operated with hydrogen as a fuel gas, but also can withstand natural gas, or more precisely: methane. Overall, he delivered since the start of the experiment 3,400 kilowatt hours of electricity - enough to supply a household with electricity for a year. Over the entire term of the stack pointed to only a very slight aging of about 0.6 percent per 1,000 hours of operation, which is reflected in a reduction of tension and the associated power loss. A refined stack from 2010 even performed slightly better: he aged only half as fast as 34,500 hours.
With the new record level of over 70,000 operating hours of the Jülich stack from 2007 solves now the previous record holder from: tubular cells of Siemens Westinghouse Power Corporation (SWPC), which had more than 69,000 hours in operation. The Jülich SOFC builds unlike those not on a ceramic tube, but on a flat ceramic surface as an anode substrate. Due to the lower internal resistance can thus achieve higher power densities at reduced temperatures.
Scientists of the research center for 20 years working on SOFC, so the abbreviation for "Solid Oxide Fuel Cell", to German "solid oxide fuel cell" for whose development they have already received 95 patents. Even the record stack consists largely of self-developed components. These include the ceramic cells, the contact layers and a special glass ceramic which is used because of the high temperatures for sealing. The material for the intermediate plates that allow the cells to form a "stack" (English for "stack) assemble, comes from the Austrian company Plansee SE, Reutte.