The Research On Anode Structure For Solid Oxide Fuel Cell

Solid oxide fuel cell (SOFC) is an all solid-state energy conversion device operated at high temperatures with the advantage of high efficiency, little pollution and no expensive metal catalyzer. SOFC attracts more and more attention allover the world for lack of power resources and environmental pollution. For improving the cell performance, influence of anode material content and manufature process on anode structure and performance is studied. The preparation of planar anode support SOFC is investigated. This paper consists of several parts as following:(1) The influence of anode material size on cell performance is discussed. The cell output performance indicates that the anode material with 1μm diameter MO powder and 1.5 μ m diameter YSZ powder has high electrical conductivity, but the reunited phenomena is observed in anode SEM image.(2) It is an effective method for improving anode porosity to put 20% (weight ratio) carbon powder into anode material. The SEM images show that the anode microstructure is appropriate. Use H2 as fuel and O2 as oxidant (the same as following) , the cell power density is up to 0.282 W/cm2 in 1000℃, more 0.05W/cm2 than the cell without carbon.(3) The different thickness(10 μm,20μ m,35 μm) anode are prepared and the cell tests imply activation polarization decreases, but the diffusing polarization and cell output density increases with anode thickness rising.(4) A new method (screen-printing) of roughening anode/electrolyte interface is presented. The output density of the cell fabricated by this method is up to 0.33 W/cm2 in 1000℃, 0.048 W/cm2 more than those of normal cell.(5) The anode support SOFC is fabricated for reducing SOFC operating temperature. Anode substrate, thin film YSZ electrolyte and LSM cathode are fabricated by dry-pressing process, spray-coating technique and slurry coating process respectively. The thickness of YSZ film is approximately 15-20 μm. The experimental results show anode support SOFC has lower activation polarization and diffusing polarization than electrolyte-supported SOFC in 800 ℃. The cell output density also increases 0.05 W/cm2, is up to 0.13 W/cm2.