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Progress Of Lithium Rich Cathode Materials For Li-Ion Batteries, Jie ZHANG, WANG Jiu-Lin, YANG Jun 2013 Chinese Chemical Society | Xiamen University

Progress Of Lithium Rich Cathode Materials For Li-Ion Batteries, Jie Zhang, Wang Jiu-Lin, Yang Jun

Journal of Electrochemistry

Lithium rich materials xLi2MnO3·(1-x)LiMO2 (0<x<1, M=Mn, Co, Ni) become a hot topic because of their high capacities exceeding 250 mAh·g-1 and low cost. However, the large irreversible capacity during the first cycle, low rate capability and structure collapse during cycling remain impediments in developing these cathodes for applications. The structure analyses and charge/discharge mechanisms for lithium rich materials are currently main research contents. Although whether the lithium rich materials are solid solutions or composite is still controversial, oxygen release mechanism on the first charge 4.5 V plateau of lithium rich materials has come to consistency. Several modifications, such as bulk doping, surface coating and microstructure …


Fabrication And Performance Of Lani0.6Fe0.4O3-δ Cathode Modified By Coating With Gd0.2Ce0.8O2 For Intermediate Temperature Solid Oxide Fuel Cell, Rui-xuan REN, Bo HUANG, Xin-jian ZHU, Yi-xing Hu, Xiao-yi DING, Zong-yao LIU, Ye-bin LIU 2013 Chinese Chemical Society | Xiamen University

Fabrication And Performance Of Lani0.6Fe0.4O3-δ Cathode Modified By Coating With Gd0.2Ce0.8O2 For Intermediate Temperature Solid Oxide Fuel Cell, Rui-Xuan Ren, Bo Huang, Xin-Jian Zhu, Yi-Xing Hu, Xiao-Yi Ding, Zong-Yao Liu, Ye-Bin Liu

Journal of Electrochemistry

The symmetric cell of LaNi0.6Fe0.4O3-δ/Sc0.1Zr0.9O1.95/LaNi0.6Fe0.4O 3-δ was fabricated with screen printing method. A LaNi0.6Fe0.4O3-δ (LNF) cathode was modified by coating with nano-sized gadolinium-doped ceria (GDC, Gd0.2Ce0.8O2) prepared using a simple combustion process within the pores of the cathode. According to the electrochemical impedance spectra (EIS), the polarization resistance of the pure LNF was 0.70 W·cm2 at 750 ºC, while 0.13 W·cm2 for the 21.3% GDC (by mass)-coated LNF …


Preparation And Electrochemical Performance Of Hollow Carbon Spheres/Sulfur Composite, Jun ZANG, Hang QIAN, Er-man ZENG, Juan-ni FU, Ming-sen ZHENG, Quan-feng DONG 2013 State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;

Preparation And Electrochemical Performance Of Hollow Carbon Spheres/Sulfur Composite, Jun Zang, Hang Qian, Er-Man Zeng, Juan-Ni Fu, Ming-Sen Zheng, Quan-Feng Dong

Journal of Electrochemistry

Hollow carbon spheres were prepared by the PMMA template. Hollow carbon spheres/sulfur composite was made from sulfur and hollow carbon spheres as a conducting framework. The results of SEM and TEM showed that sulfur was uniformly filled in both of the shell and hollow core of hollow carbon spheres. The electrochemical performance of hollow carbon spheres/sulfur composite was characterized by the charge/discharge method. The results showed the excellent rate and cycle performance of hollow carbon spheres/sulfur composite. The reversible capacities of hollow carbon spheres/sulfur composite are 1145 mAh·g-1, 824 mAh·g-1, 702 mAh·g-1, 586 mAh·g …


Influence Of Electrode Hydrophobicity On Performance Of Alkaline Polymer Electrolyte Fuel Cells, Li-sheng TAN, Jing PAN, Yao LI, Lin ZHUANG, Jun-tao LU 2013 Chinese Chemical Society | Xiamen University

Influence Of Electrode Hydrophobicity On Performance Of Alkaline Polymer Electrolyte Fuel Cells, Li-Sheng Tan, Jing Pan, Yao Li, Lin Zhuang, Jun-Tao Lu

Journal of Electrochemistry

In the present work, we study the influence of the electrode hydrophobicity on the performance of alkaline polymer electrolyte fuel cells (APEFCs). QAPS or xQAPS is employed as the membrane and the ionomer, while PTFE is used as a hydrophobic additive in order to adjust the electrode hydrophobicity. We find that enhancing the hydrophobicity of anode can promote the performance of APEFCs, while a moderate hydrophobicity of cathode is required to achieve optimal performance. By using xQAPS as the electrolyte and adding some PTFE in the anode, a peak power density of 132 mW·cm-2 can be obtained …


Polypyrrole-Transition Metal-Oxygen Coordination Complexes As High Performance Lithium Storage Material, Ya Mao, Qingyu Kong, Bingkun Guo, Zhaoxiang Wang, Liquan Chen 2013 中国科学院物理研究所新能源材料与器件北京市重点实验室,中国科学院清洁能源前沿研究重点实验室,北京凝聚态物理国家实验室,北京 100190;

Polypyrrole-Transition Metal-Oxygen Coordination Complexes As High Performance Lithium Storage Material, Ya Mao, Qingyu Kong, Bingkun Guo, Zhaoxiang Wang, Liquan Chen

Journal of Electrochemistry

No abstract provided.


Multifunctional Corrosion Inhibition Behavior Of Zn-Al Calcined Layered Double Hydroxides For Steel Rebar In Nacl Solution, Xiao-juan ZHANG, Jing-jing WANG, Shi-gang DONG, Chang-jian LIN 2013 State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian, China;

Multifunctional Corrosion Inhibition Behavior Of Zn-Al Calcined Layered Double Hydroxides For Steel Rebar In Nacl Solution, Xiao-Juan Zhang, Jing-Jing Wang, Shi-Gang Dong, Chang-Jian Lin

Journal of Electrochemistry

The Zn-Al layered double hydroxides (Zn-Al LDHs) and calcined products (Zn-Al CLDHs) were synthesized successfully under a routine air atmosphere. The results showed that both Zn-Al LDHs and Zn-Al CLDHs had obvious flake structures. The corrosion inhibition of Zn-Al CLDHs for steel rebar in NaCl solution was studied by electrochemical techniques. It was found that the corrosion rate of steel rebar decreased significantly after the steel rebar was treated by Zn-Al CLDHs in NaCl solution for 3 h. It was indicated that Zn-Al CLDHs could absorb Cl- and release OH- during their reconstruction process, which provided dual protection …


Preparation And Characterization Of A Novel Composite Electrolyte Ceria-Sulfate For Intermediate Temperature Solid Oxide Fuel Cells, Ze TONG, Yi-mei YIN, Jie-wei YIN, Zi-feng MA 2013 Chinese Chemical Society | Xiamen University

Preparation And Characterization Of A Novel Composite Electrolyte Ceria-Sulfate For Intermediate Temperature Solid Oxide Fuel Cells, Ze Tong, Yi-Mei Yin, Jie-Wei Yin, Zi-Feng Ma

Journal of Electrochemistry

A novel composite electrolyte SDC-(Li/Na)2SO4 was prepared for intermediate temperature solid oxide fuel cells (ITSOFC). The phase structure and cross-sectional morphology were examined by XRD and SEM, respectively, and the ionic conductivity was investigated by AC impedance in a temperature range of 400 oC ~ 700 oC in air. It was found that the composite electrolyte was composed of two phases: crystal SDC and amorphous (Li/Na)2SO4. The conductivity of the composite electrolyte was significantly larger than that of SDC at intermediate temperatures (550 oC ~ 700 oC) and increased …


Electrocatalytic Mechanism And Porous Electrode Mass Transfer Process In Membrane Electrode Assembly For Direct Methanol Fuel Cells, Xin-dong WANG, Yi-tuo WANG, Gui-Cheng LIU, Meng WANG, Zhe TIAN 2013 Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, China

Electrocatalytic Mechanism And Porous Electrode Mass Transfer Process In Membrane Electrode Assembly For Direct Methanol Fuel Cells, Xin-Dong Wang, Yi-Tuo Wang, Gui-Cheng Liu, Meng Wang, Zhe Tian

Journal of Electrochemistry

Direct methanol fuel cell (DMFC) is considered to be a promising commercial energy conversion device for portable electronics due to its many advantages. In order to improve the performance of DMFC, many companies and research institutes have been launching the deep research and obtaining a lot of conspicuous achievements. In this paper, the electrocatalytic mechanism and porous electrode mass transfer process in membrane electrode assembly (MEA) are analyzed. In addition, combined with the preparation process of MEA, multilayer ordered structures and internal transfer process of the cell, recent progresses of MEA in DMFC are discussed.


Electrochemical Performance Of Al-Doped Spinel Limn2O4 Cathode Material For Li-Ion Batteries, Yong-Long WANG, Wen-Ge WANG, Qian ZHANG, Xin WANG, Jian-Sheng CAO, Shi-Hai YE 2013 Chinese Chemical Society | Xiamen University

Electrochemical Performance Of Al-Doped Spinel Limn2O4 Cathode Material For Li-Ion Batteries, Yong-Long Wang, Wen-Ge Wang, Qian Zhang, Xin Wang, Jian-Sheng Cao, Shi-Hai Ye

Journal of Electrochemistry

Spinel LiMn2O4, a cathode material for Li-ion batteries, is featured as good high-rate performance, low cost and environmental friendly. The pristine and Al-doped LiMn2O4 samples were prepared by sol-gel method. The structure and micromorphology of the as-prepared samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results demonstrated that the as-prepared LiMn2O4 samples had a typical cubic spinel structure and were composed of sphere-like particles with a diameter range of 300 ~ 500 nm. Galvanostatic charge-discharge tests showed that the LiMn2O4 samples doped …


Effect Of Ethyl Propionate On Low-Temperature Performance Of Lifepo4-Based Li-Ion Battery, Xiao-ping LI, Lian-sheng HAO, Wei-shan LI, Meng-qing XU, Li-dan XING 2013 Mcnair New Power Co., Ltd, Dongguan, Guangdong 523800, China

Effect Of Ethyl Propionate On Low-Temperature Performance Of Lifepo4-Based Li-Ion Battery, Xiao-Ping Li, Lian-Sheng Hao, Wei-Shan Li, Meng-Qing Xu, Li-Dan Xing

Journal of Electrochemistry

A linear carboxylic, ester ethyl propionate (EP), was used as the co-solvent of carbonates, ethylene carbonate (EC), ethyl-methyl carbonate (EMC) and dimethyl carbonate (DMC), and its effect on low-temperature performance of LiFePO4-based Li-ion battery was studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge test. The application of EP enhances the ionic conductivity of the electrolyte, improves the compatibility of the electrolyte with both LiFePO4 and graphite materials, and thus improves the low-temperature performance of LiFePO4-based Li-ion battery. The Li-ion battery using the optimized electrolyte of 1 mol·L-1 LiPF6/EC:EMC:DMC:EP …


Influences Of The Cinnamic Acid On Zinc Electrodeposition At Glassy-Carbon Electrode, Kai LI, Shen CHEN, Shen-na LIU, Bi-sang CHEN, Heng LIN, Guo-liang CHEN, Qing-xiang WANG 2013 Chinese Chemical Society | Xiamen University

Influences Of The Cinnamic Acid On Zinc Electrodeposition At Glassy-Carbon Electrode, Kai Li, Shen Chen, Shen-Na Liu, Bi-Sang Chen, Heng Lin, Guo-Liang Chen, Qing-Xiang Wang

Journal of Electrochemistry

The influences of cinnamic acid (CIN) on the mechanism of Zn deposition and nucleation kinetics onto glassy-carbon electrode were studied by cyclic voltammetry (CV) and chronoamperometry (CA). The results revealed that the zinc reduction took place via Zn2+ + 2e → Zn in the presence of CIN, but the kinetics of zinc deposition was changed and the formation rate of zinc nuclei was accelerated. In the absence of CIN, the mechanism of zinc nucleation followed the 3D-instantaneous diffusion-controlled nucleation, while the 3D-progressive diffusion-controlled nucleation in the presence of CIN. The addition of CIN reduced the nucleation rate, but increased …


Influence Of Media Composition On The Growth Rate Of Chlorella Vulgaris And Scenedesmus Acutus Utilized For Co2 Mitigation, Czarena L. Crofcheck, Xinyi E, Aubrey Shea, Michael D. Montross, Mark Crocker, Rodney Andrews 2013 University of Kentucky

Influence Of Media Composition On The Growth Rate Of Chlorella Vulgaris And Scenedesmus Acutus Utilized For Co2 Mitigation, Czarena L. Crofcheck, Xinyi E, Aubrey Shea, Michael D. Montross, Mark Crocker, Rodney Andrews

Biosystems and Agricultural Engineering Faculty Publications

Atmospheric carbon dioxide levels have increased since the industrial revolution due to increasing combustion of fossil fuels. One possible CO2 mitigation strategy is the use of microalgae for mitigation of CO2. This paper focuses on the influence of media composition on the growth rate of two microalgae strains, Chlorella vulgaris and Scenedesmus actus. A KNO3 based medium was found to work better for Chlorella, while a urea based equivalent worked better for Scenedesmus. The urea based media investigated here resulted in growth similar to that found with previously reported KNO3 based media. …


Direct Power Control Of Dfigs Based Wind Energy Generation Systems Under Distorted Grid Voltage Conditions, Emad Gameil Shehata E. G. Shehata 2013 Electric Engineering Dept.- Faculty of Engineering- Minia University- El Minia- Egypt

Direct Power Control Of Dfigs Based Wind Energy Generation Systems Under Distorted Grid Voltage Conditions, Emad Gameil Shehata E. G. Shehata

Emad Gameil Shehata E. G. Shehata

This paper presents an improved direct power control (DPC) strategy of a wind turbine driven doubly fed induction generators (DFIGs) connected to distorted grid voltage conditions. A coordinate control strategy of the grid side converter (GSC) and rotor side converter (RSC) of the DFIG is designed to improve the overall scheme performance. The RSC is controlled based on a DPC principle to eliminate the electromagnetic torque and stator reactive power oscillations. The total active and reactive power oscillations are compensated by the GSC control to achieve constant active and reactive powers from the overall DFIG system. A current control scheme …


Voltge & Reactive Power Control In Oman Transmission System, Omar H. Abdalla, Rashid Al-Badwawi, Hilal Al-Hadi, Hisham Al-Riyami, Ahmed Al-Nadabi, Karim Karoui, Ariadne Szekut 2013 University of Helwan

Voltge & Reactive Power Control In Oman Transmission System, Omar H. Abdalla, Rashid Al-Badwawi, Hilal Al-Hadi, Hisham Al-Riyami, Ahmed Al-Nadabi, Karim Karoui, Ariadne Szekut

Omar H. Abdalla

The paper presents voltage and reactive power control in the Main Interconnected Transmission System (MITS) in the Sultanate of Oman. The objective is to improve voltage profile at substations supplying distribution companies and directly connected bulk customer. An objective function is used to maximize reactive power margin of generating units to maintain as much as possible reserves on different generators. The control parameters include existing voltage and reactive power control means, e.g. settings of generators’ excitation/AVR, transformer tap-changing, and capacitor bank switching. The constraints include operational limits of the above control devices in addition to allowable limits of busbar voltages, …


Rapid Tool Heating, Jason Chi, Bobby Dodge 2013 California Polytechnic State University - San Luis Obispo

Rapid Tool Heating, Jason Chi, Bobby Dodge

Mechanical Engineering

Quatro Composites creates various molded parts for an array of industries. They are seeking to improve their thermoplastic molding process by decreasing the amount of time to heat up the steel tool that molds the thermoplastics. Currently, it takes approximately 1 hour to heat up their 120 pound steel mold from room temperature to approximately 700°F. The goal of this project is to create an optimum heating method that will minimize that heating time to about 20 minutes or less. It is critical for the stakeholders (Quatro Composites) to have a faster heating time in order to increase their production …


Design Of An Energy Efficient Virtual End Node Client Using Openadr2.0a And Smap, Kevin Navero 2013 California Polytechnic State University, San Luis Obispo

Design Of An Energy Efficient Virtual End Node Client Using Openadr2.0a And Smap, Kevin Navero

BioResource and Agricultural Engineering

Demand Response (DR) describes the set of actions taken to impose a reduction in electrical loads to stabilize the power grid and decrease costs. It is used when power grid emergencies or extremely high demand and congestion, threaten the electricity supply-demand balance. Automated Demand Response (ADR) describes a web-based control system that triggers DR events automatically by signaling other pre-programmed control systems. This project intends to use the OpenADR2.0 specifications provided by the OpenADR Alliance to construct an open source Virtual End Node (VEN) client to retrieve DR signals. The Simple Measurement and Actuation Profile (sMAP) software is also used …


Energy Dashboard Tool For Cal Poly Dormitories, Katie Zombro 2013 California Polytechnic State University - San Luis Obispo

Energy Dashboard Tool For Cal Poly Dormitories, Katie Zombro

Electrical Engineering

This project defines the needs, uses, and future projects (as well as business cases and procurement) of a University Housing dashboard tool, utilized by the Red Brick Dormitories on the Cal Poly campus. This easily accessed tool provides simple information regarding energy trending data, allowing for all student residents no matter their academic discipline, to understand their energy trends and opportunities for reduction. With the Energy Dashboard in place, Cal Poly’s red brick dormitories experienced savings ranging from 10%-20% from the 2011-2012 school year baseline, by the end of the 2012-2013 academic year. With the help of the Dashboard, competitions …


Wind And Hydroelectric Power Simulation For The Dc House Project, Randy Lormand, Christopher Goloskie 2013 California Polytechnic State University - San Luis Obispo

Wind And Hydroelectric Power Simulation For The Dc House Project, Randy Lormand, Christopher Goloskie

Electrical Engineering

This project details the design and integration of a wind and hydroelectric power simulation system in correlation with the DC House Project. The simulator uses variable speed drives to rotate a DC motor which then drives a generator to produce output. This output is then regulated using a DC to DC converter which holds the voltage level constant making it easier to interface with other power sources for the house. The test results indicate that the simulator will be able to produce two separate power outputs that will provide at least 70 Watts of power in the acceptable speed range …


Design, Fabrication, And Testing Of An Emr Based Orbital Debris Impact Testing Platform, Jeffrey J. Maniglia Jr. 2013 California Polytechnic State University, San Luis Obispo

Design, Fabrication, And Testing Of An Emr Based Orbital Debris Impact Testing Platform, Jeffrey J. Maniglia Jr.

Master's Theses

This paper describes the changes made from Cal Poly’s initial railgun system, the Mk. 1 railgun, to the Mk. 1.1 system, as well as the design, fabrication, and testing of a newer and larger Mk. 2 railgun system. The Mk. 1.1 system is developed as a more efficient alteration of the original Mk. 1 system, but is found to be defective due to hardware deficiencies and failure, as well as unforeseen efficiency losses. A Mk. 2 system is developed and built around donated hardware from the Naval Postgraduate School. The Mk. 2 system strove to implement an efficient, augmented, electromagnetic …


Unipolar Pulse Width Modulation Inverter, Randy Baggao, Gabriel Tam 2013 California Polytechnic State University - San Luis Obispo

Unipolar Pulse Width Modulation Inverter, Randy Baggao, Gabriel Tam

Electrical Engineering

This project portrays the design and construction of a pulse width modulation (PWM) inverter. The inverter is implemented as a unipolar converter. The inverter provides a steady single-phase sinusoidal 60Hz AC voltage output from a DC input. This is a basic DC-AC power converter that is built in 3 separate phases and integrated altogether at the end. The inverter can be broken down into the control unit, firing circuit, and the H-bridge. By using the PWM method, one can control the frequency and amplitude of the output by using a reference signal. This method will also avoid using a transformer …


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