Engineering

70,000 Hours Ceramic Solid Oxide Fuel Cell

Is the fuel cell ready for wide deployment? The signs are growing. The high-temperature fuel cell of research center Jülich has managed now 70,000 hours. It runs non-stop since August 6, 2007. Thus, the practice maturity to access is close.

70,000 Hours Fuel Cell That Never Ends
Ceramic Solid Oxide Fuel Cell in front of the stove: more than eight years, the fuel cell from Research Centre “Jülich” produces electricity.

Toyota now believes that the fuel cell has earned the step from the labs in the series. Last week the Japanese pioneer had presented the first production car with fuel cell, the Toyota of Mirai. The first copies are delivered in Germany until the end of the year. The practice will show whether the Toyota Mirai is really ripe for long-term use.

Ceramic Solid Oxide Fuel Cell
So unimpressive winner look: the Solid Oxide Fuel Cell stack at Research Centre Jülich supplies for more than 70,000 hours.

The engineers are anyway, convinced that the fuel cell is just before the breakthrough at the Research Centre Jülich. The installed high-temperature fuel cell provides power tirelessly since August 6, 2007 and that since more than 70,000 hours of operation. There are now more than 70,000 hours without a break. Almost 3000 days. More than eight years. Never before a fuel cell with ceramic cells ran longer.

Electrical efficiency of up to 60% with 70,000 Hours Ceramic Solid Oxide Fuel Cell

The Jülich record fuel cell is a consisting of two cells stack powered by hydrogen as fuel gas. Since the start of the long term experiment on August 6, 2007, the cell 3400 delivered kWh of electricity. That is sufficient to provide a budget for one year with electricity. Such high temperature fuel cells provide electrical efficiencies of up to 60%, the heat can be used in addition.

“The operating temperature of 700 degrees makes enormous demands on the materials used,” said Harald Bolt, Member of the Board of the Research Centre Jülich. “We can prove with the record for the first time, that the materials we have developed also in combination are application-ready and functional over such a long period, which initially hardly anyone has kept possible.”

Fuel cells use hydrogen or gas

Ceramic high temperature cell can be operated with hydrogen or natural gas. Final product is water, carbon dioxide comes however at natural gas operation.

The cell meets for Jülich design with the world record a core demand of the car industry. A cell is to hold five to ten years and in that time 40,000 to 80,000 hours generate electricity. Otherwise the use of expensive cells not worth. If the cell has the same endurance when she is exposed to the additional stresses of driving must be seen however.

Aging of the cells cost performance

But the long-term test in Jülich occupied not only the performance of the fuel cell, but also the ageing through the operation. The cell stack to 0.6%, which is noticeable in a lowering of tension and a loss of performance age per 1000 hours of operation. You extrapolate these aging purely linear on the 70,000 hours of operation, so the performance of the cell has fallen over the past eight years by 42%.

But still lots of music is included in these figures. So, a further development of the record cell stack from the year 2010 are 34,500 hours continuous operation was aged only half as fast.

Previous record holder what Siemens Westinghouse

The FZJ researchers replaced Siemens Westinghouse Power Corporation (SWPC) as a world record holder. The company had let solid 69,000 hours electricity produce an oxide fuel cell (SOFC – solid oxide fuel cell). However, Jülich cell has a different design than the Siemens Westinghouse. The ceramics, which ensures that only ions can pass through, so that there is a charge separation, is flat. SWPC sat on a tubular ceramic.

For 20 years the Jülich researchers are working on the “solid oxide fuel cell”, what means solid oxide fuel cell. The stack with the world record fuel consists mainly of self-developed components. These include the ceramic cells, the contact layers and a special glass-ceramic to seal.

The Austrian Plansee SE company based in Reutte has supplied the material for the intermediate plates composed with which the cells to the stack.

DLR experimented with 70,000 Hours Ceramic Solid Oxide Fuel Cell

70,000 Hours Fuel Cell That Never Ends__
HY4 DLR: the plane has a fuel cell on Board that converts hydrogen and oxygen into water and electrical energy. The four passengers to sit in two separate cabins. The first flight is scheduled for mid 2016 from Stuttgart Airport.

The German Center for air and space DLR opts for the fuel cell. The DLR experimented with fuel cells, which provide the current in electric aircraft and thus increase the range compared to battery-powered electric aircraft.