| A fuel cell is an energy conversion device with a high efficiency and a lowpollution. Different from the traditional cells that can only reserve energy, it generateselectricity from fuels such as hydrogen, natural gas and other hydrocarbons. The fuelcell is also called a cell because it is composed of electrolyte, anode and cathode, whichare the same for a normal cell. The electrolyte is sandwiched by the two electrodes. Thefuel cell is also different from the traditional power generation methods. Because it isnot limited by the Carnot cycle, fuel cell has advantages of higher energy conversionefficiency and lower polluted gases emission over the traditional generator. Recentlywith the natural resource exhaustion and environment deterioration, developing efficientand environmental friendly energy techniques is necessary. Since fuel cell just matchessuch requirements, it attracts the interests all over the world.As the fourth generation fuel cell, SOFC (Solid Oxide Fuel Cell) has manyoutstanding advantages, which is better than other fuel cells. Firstly, equipped with allsolid components, it eliminates the problems that liquid electrolyte fuel cell faces, suchas corrosion and leakage of liquid electrolytes. Secondly operating at high temperatures,its electrode reaction is so fast that it is unnecessary to use noble metals as electrodes.Thus the cost of the cells can be minimized. The most outstanding advantage of SOFCis that it uses a large scale of fuels, from the hydrogen, carbon monoxide to the naturalgas or even other combustive gases.Here, we focus on the carbonate doped GDC (Gd0.1Ce0.9O0.95) and LCP(La0.16Ce0.8Pr0.04O1.9) electrolytes solid oxide fuel cell in detail. At the same time, westudy the properties of (Pr-Nd) 1-xSrxCoO3-δ(0.2≤x≤0.5) as new cathode for SOFC.First of all, GDC and LCP power were synthesized by sol-gel method(sol-gel) .Then the power was mixed with 20wt% double salt Li/Na2CO3. The singlecells were fabricated using a dry-pressing process, and their electrical conductivity,morphology, battery performance and DTA curves were analyzed. The experimentalresults show that the conductivity of the electrolyte at 400oC to 650oC increased with temperature, GDC-LiNaCO3 rate of up to 0.28S/cm (650o C) and LCP-LiNaCO3 up to0.29 S/cm (600oC). Single cell test results show that with increased the temperature ofelectrolyte, the battery's power density and current density are higher, at the same time,the open circuit voltage of LCP-LiNaCO3 electrolyte was about 09V. The maximumpower density of the cell with the LCP-LiNaCO3 and GDC-LiNaCO3 compositeelectrolyte were 230mWcm-2, 124mW/cm2 respectively. The result showed theproperties of LCP-LiNaCO3 were better than GDC-LiNaCO3 as electrolyte.In our study, Cathode materials consisting of (Pr-Nd)1-xSrxCoO3-δ(0.2≤x≤0.5) wereprepared by using the combustion method for intermediate-temperature solid-oxide fuelcells (IT-SOFCs). (Pr-Nd)1-xSrxCoO3-δ(0.2≤x≤0.5) had an single phase after sintering at1000°C for 2h. The electrical conductivities were all higher than 370 S/cm, which metthe demand for IT-SOFC. Using impedance spectra, the electrochemicalperformance of PNSC–SDC composite cathode in the temperature range of 650-800oCon SDC electrolyte, and the effect of sintering temperature on performance of cathodewere investigated. The area specific resistance (ASR) of PNSC4–SDC sintered at1000oC on SDC electrolyte has the lowest value, 0.049Ωcm2 at 850oC and 0.146Ωcm2at 750oC. We also tested the overpotential for PSCF-GDC composite cathode, it can bepredicted that the weak polarization properties of this cathode can improve performanceof electrode significantly, and the PNSC-SDC composite cathode is a potential cathodematerial. We measured the power densities of the SDC-supported fuel cells by usingPNSC-SDC as composite cathode. The maximum power density of the cell with thePNSC-SDC composite cathode was 355mWcm-2, 274mWcm-2 and 194mWcm-2 at850oC, 800oC and 750oC, respectively.
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