An electrolyte model for the solid oxide fuel cell (SOFC) with proton conducting perovskite electrolyte is developed in this study, in which four types of charge carriers including proton, oxygen vacancy (oxide ion), ...An electrolyte model for the solid oxide fuel cell (SOFC) with proton conducting perovskite electrolyte is developed in this study, in which four types of charge carriers including proton, oxygen vacancy (oxide ion), free electron and electron hole are taken into consideration. The electrochemical process within the SOFC with hydrogen as the fuel is theoretically analyzed. With the present model, the effects of some parameters, such as the thickness of electrolyte, operating temperature and gas composition, on the ionic transport (or gas permeation) through the electrolyte and the electrical performance, i.e., the electromotive force (EMF) and internal resistance of the cell, are investigated in detail. The theoretical results are tested partly by comparing with the experimental data obtained from SrCe0.95M0.05O3-α, (M=Yb, Y) cells.展开更多
This study combines the three-dimensional model of the high-temperature proton exchange membrane fuel cell(HT-PEMFC)with theoretical analysis,by optimizing the structure of the fuel cell,adding a semicircular baffle i...This study combines the three-dimensional model of the high-temperature proton exchange membrane fuel cell(HT-PEMFC)with theoretical analysis,by optimizing the structure of the fuel cell,adding a semicircular baffle in the gas channel and implementing novelly arranged obstacles to improve the PEMFC performance. The effects of velocity distribution,interface reactant concentration and pressure drop on performance are studied. The results show that adding obstacles in the gas channel will produce vertical velocity and can improve output performance,especially in the case of high current density and higher baffle radius. The superiority of the optimized structure in mass transfer capacity is proved,and a mechanism explanation is given for the improvement of performance.展开更多
The purpose of this study is to point out the dominant factor of heat and mass distribution in single-cell PEFC (polymer electrolyte fuel cell). The numerical simulation by simple 3D model to clarify the influence o...The purpose of this study is to point out the dominant factor of heat and mass distribution in single-cell PEFC (polymer electrolyte fuel cell). The numerical simulation by simple 3D model to clarify the influence of cell components structure on heat and mass transfer phenomena as well as power generation experiment and measurement of in-plane temperature distribution by thermograph was carried out. From the simulation, the gas channel pitch of separator was the key factor to unify in-plane distribution of temperature and gas concentration on reaction surface in cell. The compression of GDL (gas diffusion layer) by cell binding caused wider distribution of mass concentration in GDL. From the experiment, the power generation performance was promoted with decreasing gas channel pitch. The temperature range in observation area was reduced with decreasing gas channel pitch. It can be concluded that the power generation performance is promoted by decreasing gas channel pitch.展开更多
Ceramic BaCe0.8Ho0.2O3-α with orthorhombic perovskite structure was prepared by conventional solid state reaction, and its conductivity and ionic transport number were measured by ac impedance spectroscopy and gas co...Ceramic BaCe0.8Ho0.2O3-α with orthorhombic perovskite structure was prepared by conventional solid state reaction, and its conductivity and ionic transport number were measured by ac impedance spectroscopy and gas concentration cell methods in the temperature range of 600-1000 ℃ in wet hydrogen and wet air, respectively. Using the ceramics as solid electrolyte and porous platinum as electrodes, the hydrogen-air fuel cell was constructed, and the cell performance at temperature from 600-1000 ℃ was examined. The results indicate that the specimen was a pure protonic conductor with the protonic transport number of 1 at temperature from 600-900 ℃ in wet hydrogen, a mixed conductor of proton and electron with the protonic transport number of 0.99 at 1000 ℃. The electronic conduction could be neglected in this case, thus the total conductivity in wet hydrogen was approximately regarded as protonic conductivity. In wet air, the specimen was a mixed conductor of proton, oxide ion and electron hole. The protonic transport numbers were 0.01-0.09, and the oxide-ionic transport numbers were 0.27-0.32. The oxide ionic conductivity was increased with the increase of temperature, but the protonic conductivity displayed a maximum at 900 ℃, due to the combined increase in mobility and depletion of the carriers. The fuel cell could work stably. At 1000 ℃, the maximum short-circuit current density and power output density were 346 mA/cm^2 and 80 mW/cm^2, respectively.展开更多
文摘An electrolyte model for the solid oxide fuel cell (SOFC) with proton conducting perovskite electrolyte is developed in this study, in which four types of charge carriers including proton, oxygen vacancy (oxide ion), free electron and electron hole are taken into consideration. The electrochemical process within the SOFC with hydrogen as the fuel is theoretically analyzed. With the present model, the effects of some parameters, such as the thickness of electrolyte, operating temperature and gas composition, on the ionic transport (or gas permeation) through the electrolyte and the electrical performance, i.e., the electromotive force (EMF) and internal resistance of the cell, are investigated in detail. The theoretical results are tested partly by comparing with the experimental data obtained from SrCe0.95M0.05O3-α, (M=Yb, Y) cells.
基金supported by the De-fense Industrial Technology Development Program (No. JCKY2018605B006)the Aviation Science Fund (No. 201928052002)
文摘This study combines the three-dimensional model of the high-temperature proton exchange membrane fuel cell(HT-PEMFC)with theoretical analysis,by optimizing the structure of the fuel cell,adding a semicircular baffle in the gas channel and implementing novelly arranged obstacles to improve the PEMFC performance. The effects of velocity distribution,interface reactant concentration and pressure drop on performance are studied. The results show that adding obstacles in the gas channel will produce vertical velocity and can improve output performance,especially in the case of high current density and higher baffle radius. The superiority of the optimized structure in mass transfer capacity is proved,and a mechanism explanation is given for the improvement of performance.
文摘The purpose of this study is to point out the dominant factor of heat and mass distribution in single-cell PEFC (polymer electrolyte fuel cell). The numerical simulation by simple 3D model to clarify the influence of cell components structure on heat and mass transfer phenomena as well as power generation experiment and measurement of in-plane temperature distribution by thermograph was carried out. From the simulation, the gas channel pitch of separator was the key factor to unify in-plane distribution of temperature and gas concentration on reaction surface in cell. The compression of GDL (gas diffusion layer) by cell binding caused wider distribution of mass concentration in GDL. From the experiment, the power generation performance was promoted with decreasing gas channel pitch. The temperature range in observation area was reduced with decreasing gas channel pitch. It can be concluded that the power generation performance is promoted by decreasing gas channel pitch.
基金Project supported by the National Natural Science Foundation of China (No. 20171034) and the Natural Science Foundation of Education Department of Jiangsu Province (No. 04KID150218).
文摘Ceramic BaCe0.8Ho0.2O3-α with orthorhombic perovskite structure was prepared by conventional solid state reaction, and its conductivity and ionic transport number were measured by ac impedance spectroscopy and gas concentration cell methods in the temperature range of 600-1000 ℃ in wet hydrogen and wet air, respectively. Using the ceramics as solid electrolyte and porous platinum as electrodes, the hydrogen-air fuel cell was constructed, and the cell performance at temperature from 600-1000 ℃ was examined. The results indicate that the specimen was a pure protonic conductor with the protonic transport number of 1 at temperature from 600-900 ℃ in wet hydrogen, a mixed conductor of proton and electron with the protonic transport number of 0.99 at 1000 ℃. The electronic conduction could be neglected in this case, thus the total conductivity in wet hydrogen was approximately regarded as protonic conductivity. In wet air, the specimen was a mixed conductor of proton, oxide ion and electron hole. The protonic transport numbers were 0.01-0.09, and the oxide-ionic transport numbers were 0.27-0.32. The oxide ionic conductivity was increased with the increase of temperature, but the protonic conductivity displayed a maximum at 900 ℃, due to the combined increase in mobility and depletion of the carriers. The fuel cell could work stably. At 1000 ℃, the maximum short-circuit current density and power output density were 346 mA/cm^2 and 80 mW/cm^2, respectively.