| Fuel cell is a kind of the fuel by the direct conversion of chemical energy into electrical energy in chemical devices, also known as electrochemical generator. As the fuel cell through the electrochemical reaction to the chemical energy of fuel in some of the Gibbs free energy conversion into electrical energy, Carnot cycle effects are not restricted, so efficient and low pollution, no noise. Relatively traditional power supply has many advantages, since the beginning of the 21st Century, fuel cell research is developing rapidly and has already shown to enter the commercialization stage. Rapid progress in the current study is the FC direct methanol fuel cell (DCFC), proton exchange membrane fuel cell (PEMFC), solid oxide fuel cell (SOFC). And solid oxide fuel cell with multi-fuel adaptability, simple structure, high energy conversion rate, and cell waste heat can be generated by a joint power supply as a source of heat other parts of the system used to achieve a combined heat and power, so as to more effectively improve the entire power system efficiency, the power supply at the regional aspects of SOFC promising.And compared to traditional single battery, fuel cell is an electrochemical device, has no difference with ordinary battery. Monomer has both positive and negative battery electrodes and electrolyte composition, anode is the oxidizer electrode, negative electrode of the fuel electrode, the active substance of ordinary batteries are placed directly on the internal battery, so this limits the battery capacity. Fuel cell is negative in itself does not contain any active substance, which is only a component of catalytic converters. Thus, FC can be said to be worthy of the name of the chemical energy to electricity energy converter, the battery at work, fuel and oxidizer by the external supply, so in principle, continue to enter as long as the reactants, products continue to discharge, the fuel cell will be able to continuous discharge.Here, mainly on the carbonate doped CeO2-based solid oxide fuel cell research in detail.First of all, by sol - gel method (sol-gel) synthesized nano-GDC, were mixed in three different double salt: Li2CO353mol% and Na2CO347mol%, Li2CO353mol% and SrCO347, mol%, and BaCO353mol and SrCO347mol%. Each of them with the ratio of GDC composite of 10%, 20% and 30% respectively. The single cells were fabricated using a dry-pressing process, and their electrical conductivity, morphology, battery performance and DTA curves are analyzed.The experimental results show that the conductivity of the electrolyte to complex LiNaCO3 the highest conductivity, at 400℃to 650℃between the carbonate doped with increased volume, increased with temperature and increase the conductivity of which LiNaCO330% rate of up to 0.32Scm-1 (625℃). Electrolyte doped Li2/SrCO3 maximum 0.006Scm-1, is mixed in 20% of the components obtained when the electrical conductivity with the salt content is not increased because the salt content of 30% and 10% The results are very similar content. GDC doped Ba/SrCO3 poor conductivity, the maximum is only 0.005Scm-1, and the conductivity of salt mixed with the volume on the decline. The various components of the SEM results showed that, with the parameters of salt increased, the complex salt with the GDC, the better. However, in trials, the proportion of salt, after more than 30% of the cells will decrease structural strength, so the experiment is the ratio of salt to 30% so far. Single cell test results show that with LiNaCO3 increased as the temperature of electrolyte, the battery's power density and current density are higher; at 500℃below the open circuit voltage is very small, that after more than 500℃in between 0.8V and 0.9V. Doped Li2/SrCO3 maximum power in 20% of the components obtained, 100mWcm-2 (650℃). Doped Ba/SrCO3 no power output. From three different salt compound and electrolyte content of the tests found that the performance of electrolyte into the molten completely dependent on the state of the carbonate ion conductivity. Lower melting point LiNaCO3 in doped compounds, the single-cell performance mixed with the amount of salt increases. Ba/SrCO3 doped in the complex, because of the high melting point of salt, the salt in the crystalline state failed to improve the performance of electrolyte, and along with the increase in salt content, but the performance of single-cell decline, because the crystalline salt hindered oxygen ionic conductivity of GDC. In short, manage to find ways to reduce the operating temperature of the electrolyte to improve the ionic conductivity at low temperatures is the low-temperature solid oxide fuel cell of the main research directions.
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