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Full-Text Articles in Mechanical Engineering

A New Solid Oxide Molybdenum–Air Redox Battery, Xuan Zhao, Yunhui Gong, Xue Li, Nansheng Xu, Kevin Huang Feb 2015

A New Solid Oxide Molybdenum–Air Redox Battery, Xuan Zhao, Yunhui Gong, Xue Li, Nansheng Xu, Kevin Huang

Kevin Huang

A new type of rechargeable molybdenum–air battery based on the technologies of reversible solid oxide fuel cells and chemical looping is reported in this study. The reversible solid oxide fuel cell serves as the electrical unit to realize the charging and discharging cycles while a pair of Mo/MoO2 redox couple integrated with the reversible solid oxide fuel cell stores electrical energy via an H2–H2O oxygen shuttle. The specific charge of the new battery reaches 1117 A h per kg-Mo at 550°C, which is 45% higher than the non-rechargeable Mo–air battery. The corresponding discharge specific energy ...


Characterization Of Sr‐Doped Lamno3 And Lacoo3 As Cathode Materials For A Doped Lagao3 Ceramic Fuel Cell, Kevin Huang, Man Feng, John B. Goodenough, Michael Schmerling Feb 2015

Characterization Of Sr‐Doped Lamno3 And Lacoo3 As Cathode Materials For A Doped Lagao3 Ceramic Fuel Cell, Kevin Huang, Man Feng, John B. Goodenough, Michael Schmerling

Kevin Huang

Energy dispersive spectrometry line scan and ac impedance spectroscopy were used in this study to investigate the chemical reactions between two cathode materials, La0.84Sr0.16MnO3 (LSM), La0.5Sr0.5CoO3-δ (LSC), and the electrolyte La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM). Significant interdiffusions of Co into LSGM and Ga into LSC were found at an LSC/LSGM interface even at relatively low fabrication temperatures. In contrast, only small interdiffusions of Mn into LSGM and Ga into LSM were detected at the ...


Combining Proton Conductor Bazr0.8Y0.2O3-Δ With Carbonate: Promoted Densification And Enhanced Proton Conductivity, Xue Li, Nansheng Xu, Lingling Zhang, Kevin Huang Feb 2015

Combining Proton Conductor Bazr0.8Y0.2O3-Δ With Carbonate: Promoted Densification And Enhanced Proton Conductivity, Xue Li, Nansheng Xu, Lingling Zhang, Kevin Huang

Kevin Huang

No abstract provided.


H3Po4-Imbibed Three-Dimensional Polyacrylamide/Polyacrylamide Hydrogel As A High-Temperature Proton Exchange Membrane With Excellent Acid Retention, Qunwei Tang, Guoging Qian, Kevin Huang Feb 2015

H3Po4-Imbibed Three-Dimensional Polyacrylamide/Polyacrylamide Hydrogel As A High-Temperature Proton Exchange Membrane With Excellent Acid Retention, Qunwei Tang, Guoging Qian, Kevin Huang

Kevin Huang

We herein report the use of polyacrylamide/polyacrylamide interpenetrating polymer network (PAM/PAM IPN) hydrogel as a matrix to imbibe proton conducting H3PO4, forming a robust proton exchange membrane (PEM) suitable for high-temperature PEM fuel cells by combining excellent acid retention, simple synthesis, and low cost. Its extraordinary ability to absorb large quantity of aqueous solution is fully utilized to achieve high H3PO4 loading, showing a proton conductivity of 0.0833 S cm−1 at 183 °C in dry air. The synthesized membrane also shows excellent acid retention even under mechanical load and high humidity. These profound advantages along with ...


Sol-Gel Synthesis Of A New Oxide-Ion Conductor Sr- And Mg-Doped Lagao3 Perovskite, Kevin Huang, Man Feng, John Goodenough Feb 2015

Sol-Gel Synthesis Of A New Oxide-Ion Conductor Sr- And Mg-Doped Lagao3 Perovskite, Kevin Huang, Man Feng, John Goodenough

Kevin Huang

No abstract provided.


A Novel Intermediate-Temperature All Ceramic Iron–Air Redox Battery: The Effect Of Current Density And Cycle Duration, Xuan Zhao, Xue Li, Yunhui Gong, Nansheng Xu, Kevin Huang Feb 2015

A Novel Intermediate-Temperature All Ceramic Iron–Air Redox Battery: The Effect Of Current Density And Cycle Duration, Xuan Zhao, Xue Li, Yunhui Gong, Nansheng Xu, Kevin Huang

Kevin Huang

We here report the energy storage characteristics of a new all ceramic iron–air redox battery comprising of a reversible solid oxide fuel cell as the charger/discharger and a Fe–FeOx redox couple as the chemical storage bed. The effects of current density and cycle duration on specific energy and round trip efficiency of the new battery have been systematically studied at 650°C and 550°C. The results explicitly show that current density is the most influential variable on the performance, signifying the importance of improving electrochemical performance of the reversible solid oxide fuel cell.


High Conductivity Mixed Oxide-Ion And Carbonate-Ion Conductors Supported By A Prefabricated Porous Solid-Oxide Matrix, Lingling Zhang, Xue Li, Siwei Wang, Kevin Romito, Kevin Huang Feb 2015

High Conductivity Mixed Oxide-Ion And Carbonate-Ion Conductors Supported By A Prefabricated Porous Solid-Oxide Matrix, Lingling Zhang, Xue Li, Siwei Wang, Kevin Romito, Kevin Huang

Kevin Huang

No abstract provided.


Beneficial Effects Of Mg-Excess In La1-XSrXGa1-YMgY + ZO3-Δ As Solid Electrolyte, Xuan Zhao, Xue Li, Nansheng Xu, Kevin Huang Feb 2015

Beneficial Effects Of Mg-Excess In La1-XSrXGa1-YMgY + ZO3-Δ As Solid Electrolyte, Xuan Zhao, Xue Li, Nansheng Xu, Kevin Huang

Kevin Huang

One of the paramount obstacles to the commercialization of La1-xSrxGa1-yMgyO3-δ (LSGM)-based intermediate-temperature solid oxide fuel cells is the high cost and low mechanical strength associated with the use of Ga2O3. We demonstrate in this study the use of excess Mg-doping on Ga-site as a means of lowering cost and potentially increasing mechanical strength of the final LSGM product. Conventional techniques such as XRD, SEM and AC impedance spectroscopy are applied to characterize the synthesized Mg-excess La0.8Sr0.2Ga0.83Mg0.17 + zO3-δ. The microstructures revealed by SEM indicate an increased appearance of the Mg-rich second phase along the grain-boundaries with ...


Development Of Delta-Type High Power Density Solid Oxide Fuel Cells At Siemens Stationary Fuel Cells, Kevin Huang Feb 2015

Development Of Delta-Type High Power Density Solid Oxide Fuel Cells At Siemens Stationary Fuel Cells, Kevin Huang

Kevin Huang

This paper describes recent development in Siemens Stationary Fuel Cells of Delta-type high power density solid oxide fuel cells, the foundation for future high power and high efficiency electrical power generation. Relatively high-level overviews are given in the areas of cell materials, basic cell design, basic bundle design and basic module design. The testing results of six-cell Delta 9 bundle and single Delta 8 cell are particularly highlighted to demonstrate the unique advantage of high power density and high total power presented by Delta geometry.


Mixed Oxide-Ion And Carbonate-Ion Conductors (Moccs) As Electrolyte Materials For Solid Oxide Fuel Cells, Xue Li, Guoliang Xiao, Seung Min Lee, Kevin Huang Feb 2015

Mixed Oxide-Ion And Carbonate-Ion Conductors (Moccs) As Electrolyte Materials For Solid Oxide Fuel Cells, Xue Li, Guoliang Xiao, Seung Min Lee, Kevin Huang

Kevin Huang

A systematic investigation on the effective ionic conductivity (σm) of a novel intermediate temperature mixed oxide-ion and carbonate-ion conductor (MOCC) consisting of a ceria and a carbonate is reported. The study explicitly shows that the observed remarkable temperature-dependent σm is primarily the result of softening/melting of the carbonate phase as the physical state of the carbonate phase transforms from solid, softened to molten. DSC analysis complements the understanding of the observed electrical behavior by revealing temperatures of melting and solidification in agreement with the onset temperatures of σm. In addition, the measured σm agrees reasonably well with those simulated ...


Silver-Molten Carbonate Composite As A New High-Flux Membrane For Electrochemical Separation Of Co2 From Flue Gas, Nansheng Xu, Xue Li, Maxwell Franks, Hailei Zhao, Kevin Huang Feb 2015

Silver-Molten Carbonate Composite As A New High-Flux Membrane For Electrochemical Separation Of Co2 From Flue Gas, Nansheng Xu, Xue Li, Maxwell Franks, Hailei Zhao, Kevin Huang

Kevin Huang

No abstract provided.


High Co2 Permeation Flux Enabled By Highly Interconnected Three-Dimensional Ionic Channels In Selective Co2 Separation Membranes, Lingling Zhang, Nansheng Xu, Xue Li, Siwei Wang, Kevin Huang, William Harris, Wilson Chiu Feb 2015

High Co2 Permeation Flux Enabled By Highly Interconnected Three-Dimensional Ionic Channels In Selective Co2 Separation Membranes, Lingling Zhang, Nansheng Xu, Xue Li, Siwei Wang, Kevin Huang, William Harris, Wilson Chiu

Kevin Huang

Abatement of CO2 emissions from existing fossil-fueled power plants is currently the sole near-term solution to stabilize CO2 concentration in the atmosphere. Separation and capture of CO2from process streams of these power plants is the first step toward this effort. In this paper, we report a high flux membrane consisting of highly and efficiently interconnected three-dimensional ionic channels prepared from a combined “co-precipitation” and “sacrificial-template” synthesis. The membranes exhibit remarkable CO2 permeation characteristic, achieving a CO2 flux density two orders of magnitude higher than other similar systems reported in the literature. The experimental results also have an excellent agreement with ...


Fuel Utilization And Fuel Sensitivity Of Solid Oxide Fuel Cells, Kevin Huang Feb 2015

Fuel Utilization And Fuel Sensitivity Of Solid Oxide Fuel Cells, Kevin Huang

Kevin Huang

No abstract provided.


Sr‐ And Ni‐Doped Lacoo3 And Lafeo3 Perovskites: New Cathode Materials For Solid‐Oxide Fuel Cells, Kevin Huang, Hee Y. Lee, John B. Goodenough Feb 2015

Sr‐ And Ni‐Doped Lacoo3 And Lafeo3 Perovskites: New Cathode Materials For Solid‐Oxide Fuel Cells, Kevin Huang, Hee Y. Lee, John B. Goodenough

Kevin Huang

An improved cathode material for a solid‐oxide fuel cell would be a mixed electronic and oxide‐ion conductor with a good catalytic activity for oxygen reduction at an operating temperature T op ≥ 700°C and a thermal expansion matched to that of the electrolyte and interconnect. We report on the properties of Sr‐ and Ni‐doped LaCoO3 and LaFeO3 perovskites that meet these criteria. Single‐phase regions were determined by X‐ray diffraction, and thermogravimetric analysis measurements were used to obtain the temperatures above which oxygen loss, and hence oxide‐ion conductivity, occurs. The conductivity and Seebeck ...


Activity Of Bi2O3 In Bi2O3 Y2O3 Oxygen Ion Conductor, Kevin Huang, Changzhen Wang, Xiuguang Xu Feb 2015

Activity Of Bi2O3 In Bi2O3 Y2O3 Oxygen Ion Conductor, Kevin Huang, Changzhen Wang, Xiuguang Xu

Kevin Huang

No abstract provided.


Heat Conduction And Seebeck Effect In Oxygen Cell, Kevin Huang, Yuhua Xia, Qingguo Liu Feb 2015

Heat Conduction And Seebeck Effect In Oxygen Cell, Kevin Huang, Yuhua Xia, Qingguo Liu

Kevin Huang

No abstract provided.


A Reversible And Stable Flake-Like Licoo2 Cathode For Lithium Ion Batteries, Tao Wei, Rui Zeng, Yongming Sun, Yunhui Huang, Kevin Huang Feb 2015

A Reversible And Stable Flake-Like Licoo2 Cathode For Lithium Ion Batteries, Tao Wei, Rui Zeng, Yongming Sun, Yunhui Huang, Kevin Huang

Kevin Huang

A dense and thick flake-like cathode structure was demonstrated to have a preferential crystallographic orientation for Li+ migration and a better tolerance to cracking, both of which enable a reversible and stable capacity at moderate rates from 0.1 to 2 C.


Study Of A Renewable Biomass Powered Sofc, Yunhui Gong, Andrew Chien, Zhengping Mao, Kevin Huang Feb 2015

Study Of A Renewable Biomass Powered Sofc, Yunhui Gong, Andrew Chien, Zhengping Mao, Kevin Huang

Kevin Huang

The objective of this work is to explore a solution to utilize biomass carbon by a tubular solid oxide fuel cell integrated with an "in-situ" steam gasification reactor. Non-catalyzed and catalyzed coconut shell carbons were employed as solid fuels, which were directly converted to gaseous fuels to feed the SOFC operated at 800°. Single cells showed variable electrochemical performances according to the catalytic additives. Sample without catalysts exhibited low power density, while those with catalysts such as Fe2O3 and K2CO3 showed higher performances. The enhanced cell performance with catalysts was considered to be the ...


Standard Gibbs Free Energy Of Formation Of Zros, Whi-Tong Sui, Xing-Yi Xiao, Kevin Huang, Chang-Zhen Wang Feb 2015

Standard Gibbs Free Energy Of Formation Of Zros, Whi-Tong Sui, Xing-Yi Xiao, Kevin Huang, Chang-Zhen Wang

Kevin Huang

No abstract provided.


Synthesis And Electrical Properties Of Dense Ce0.9Gd0.1O1.95 Ceramics, Kevin Huang, Man Feng, John Goodenough Feb 2015

Synthesis And Electrical Properties Of Dense Ce0.9Gd0.1O1.95 Ceramics, Kevin Huang, Man Feng, John Goodenough

Kevin Huang

No abstract provided.


A New Electrochemical Sensor For Rapid Determination Of Silicon Content In Carbon Saturate Iron, Kevin Huang, Weijiang Wu, Qingguo Liu Feb 2015

A New Electrochemical Sensor For Rapid Determination Of Silicon Content In Carbon Saturate Iron, Kevin Huang, Weijiang Wu, Qingguo Liu

Kevin Huang

No abstract provided.


Gas-Diffusion Process In A Tubular Cathode Substrate Of A Sofc, Part Ii: Identification Of Gas-Diffusion Process Using Ac Impedance Method, Kevin Huang Feb 2015

Gas-Diffusion Process In A Tubular Cathode Substrate Of A Sofc, Part Ii: Identification Of Gas-Diffusion Process Using Ac Impedance Method, Kevin Huang

Kevin Huang

The effects of cathodic dc bias, bulk pO2, and effective O2 -diffusivity on ac impedance spectra of Siemens Westinghouse Power Corporation’s cathode-supported solid oxide fuel cells were systematically studied over a temperature range of 800 to 1000°C. It was found that the activation process dominated the overall electrode kinetics at 800°C, by which the applied dc bias reduced the electrode resistance considerably. With increasing the temperature to above 900°C, the activation process became effectively activated, leading to a visible arc at the lowest frequency on the impedance spectrum, which is relevant to the pore gas-diffusion process ...


Bi2O3-Y2O3-Ceo2 Solid Solution Oxide-Ion Electrolyte, Kevin Huang, Man Feng, John Goodenough Feb 2015

Bi2O3-Y2O3-Ceo2 Solid Solution Oxide-Ion Electrolyte, Kevin Huang, Man Feng, John Goodenough

Kevin Huang

No abstract provided.


The Diffusivity And Solubility Of Oxygen In Reference Electrodes Ni-Nio, Co-Coo, Fe-Feo And Mo-Moo2 Systems, Kevin Huang, Shaohua Tang, Qingguo Liu Feb 2015

The Diffusivity And Solubility Of Oxygen In Reference Electrodes Ni-Nio, Co-Coo, Fe-Feo And Mo-Moo2 Systems, Kevin Huang, Shaohua Tang, Qingguo Liu

Kevin Huang

No abstract provided.


Cyclic Durability Of A Solid Oxide Fe-Air Redox Battery Operated At 650°C, Xuan Zhao, Yunhui Gong, Xue Li, Nansheng Xu, Kevin Huang Feb 2015

Cyclic Durability Of A Solid Oxide Fe-Air Redox Battery Operated At 650°C, Xuan Zhao, Yunhui Gong, Xue Li, Nansheng Xu, Kevin Huang

Kevin Huang

The recently developed rechargeable solid oxide metal-air redox battery has shown a great potential for applications in mid- to large-scale stationary energy storage. Cyclic durability is one of the most important requirements for stationary energy storage. In this study, we report the cyclic durability of a solid oxide Fe-air redox battery operated at 650◦C. The battery was continuously cycled 100 times under a current density of 50 mA/cm2 with rather flat performance, producing an average specific energy of 760 Wh/kg-Fe at a round-trip efficiency of 55.5%. The post-test examination indicated that the performance losses could arise ...


Effects Of Testing Configurations And Cell Geometries On The Performance Of A Sofc: A Modeling Approach, Daan Cui, Chenghao Yang, Kevin Huang, Fanglin Chen Feb 2015

Effects Of Testing Configurations And Cell Geometries On The Performance Of A Sofc: A Modeling Approach, Daan Cui, Chenghao Yang, Kevin Huang, Fanglin Chen

Kevin Huang

No abstract provided.


Combustion-Assisted Co2 Capture Using Mecc Membranes, Steven Sherman, Joshua Gray, Kyle Brinkman, Kevin Huang Feb 2015

Combustion-Assisted Co2 Capture Using Mecc Membranes, Steven Sherman, Joshua Gray, Kyle Brinkman, Kevin Huang

Kevin Huang

No abstract provided.


Reduced Area Specific Resistance For Iron-Based Metallic Interconnects By Surface Oxide Coatings, Kevin Huang, Peggy Hou, John Goodenough Feb 2015

Reduced Area Specific Resistance For Iron-Based Metallic Interconnects By Surface Oxide Coatings, Kevin Huang, Peggy Hou, John Goodenough

Kevin Huang

No abstract provided.


Wet Chemical Synthesis Of Sr- And Mg-Doped Lagao3, A Perovskite-Type Oxide-Ion Conductor, Kevin Huang, John Goodenough Feb 2015

Wet Chemical Synthesis Of Sr- And Mg-Doped Lagao3, A Perovskite-Type Oxide-Ion Conductor, Kevin Huang, John Goodenough

Kevin Huang

No abstract provided.


Hydrophobic Hydrogel Caged H3Po4 As A New Class Of High-Temperature Proton Exchange Membranes With Enhanced Acid Retention, Qunwei Tang, Guoging Qian, Kevin Huang Feb 2015

Hydrophobic Hydrogel Caged H3Po4 As A New Class Of High-Temperature Proton Exchange Membranes With Enhanced Acid Retention, Qunwei Tang, Guoging Qian, Kevin Huang

Kevin Huang

We herein report a new class of high-temperature proton exchange membranes comprised of poly(acrylic acid-graft-hexadecyltrimethylammonium bromide) (PAA-g-CTAB) or poly(acrylic acid)-graft-poly(ethylene glycol) (PAA-g-PEG) hydrophobic hydrogel caged H3PO4. The membranes exhibit reasonable proton conductivity, enhanced H3PO4 retention ability and low solubility in water, making them promising as potential high performance and robust electrolytes for high-temperature proton exchange membrane fuel cells. Although the proton conductivity is still lower than that of H3PO4 doped PBI membranes, the new concept provides a different approach to proton exchange membranes for acid retention.