Power and Energy Commons^™

Effects Of Different Carbon Sources On Performance Of Li3V2(Po4)3/C Composite Cathode Materials, Kai-Yuan Liu, Jian-Shu Huang, Li Yang

Journal of Electrochemistry

The monoclinic Li₃V₂(PO₄)₃ cathode materials were prepared by carbothermal reduction method,with methyl cellulose, chitosan(crab shells) or glucose anhydrous as carbon sources, respectively.The crystal structures, morphologies and the electrochemical performances were characterized by XRD, SEM and electrochemical measurement. The XRD patterns show that the samples obtained at 800 ℃ for 6 h have a pure monoclinic structure,which indicates that the carbon exists in amorphous phase. Electrochemical measurements show that the difference of carbon sources has a significant influence on the electrochemical properties of the materials. The Li₃V₂(PO₄)_{3 …}

Performance Of Sulfur-Super Conductive Carbon Black Composite In Electrolyte Mixed With Room Temperature Ionic Liquid, Bo Zhang, Si-Ting Chen, Xue-Ping Gao

Journal of Electrochemistry

The sulfur-super conductive carbon black composite was prepared as cathode material of lithium/sulfur battery.The composite was characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),and electrochemical impedance spectroscopy(EIS).The sulfur composite shows a high discharge capacity and a good cycle performance in electrolyte mixed with 50% of room temperature ionic liquid.In particular,the discharge capacity of the composite was stabilized at 483.6 mAh/g after 50 cycles.

Preparation And Characterizations Of Li3V2(Po4)3 Cathode Material For Lithium Ion Batteries, Hong Chen, Tao Jiang, Chun-Zhong Wang, Gang Chen, Ying-Jin Wei

Journal of Electrochemistry

The carbon-coated Li₃V₂(PO₄)₃ was prepared by carbothermal reduction method.The structural and morphological properties of the material were studied by X-ray diffraction,FTIR and transmission electron microscopy.The synthesized material was a pure phase of Li₃V₂(PO₄)₃,with the particle size of about 100 nm.The values of Li ion diffusion coefficient of the material in the potential window of 3.0 ～ 4.3 V were nearly 3 orders larger than those in 3.0 ～ 4.8 V.In addition,the charge-transfer resistances in 3.0 ～ 4.3 V were much smaller than those in 3.0 …

Investigation Of Ceo2 As Cathode Electrocatalyst For Direct Borohydride Fuel Cell, Xue-Min Ni, Ya-Dong Wang, Mu Pan

Journal of Electrochemistry

The performance of CeO₂ as oxygen reduction electrocatalyst in direct borohydride fuel cell was investigated.The experimental results indicate that CeO₂ shows significant electrocatalytic performance for oxygen reduction and exhibits no observed promotion effect on hydrolysis or electro-oxidation of BH₄^-.The power density of experimental one-compartment fuel cell with CeO₂ as cathode electrocatalyst can reach a 67.8 mW·cm^-2 at room temperature.

Preparation And Electrochemical Behavior Of Li4Ti5O12 Nanosheets As Anode Material For Lithium Ion Battery, Yi-Fei Wang, Yu-Feng Tang, Zheng Qiu, Li Yang

Journal of Electrochemistry

Spinel lithium titanate(Li₄Ti₅O₁₂) nanosheets with a size range of 200 ～400 nm were synthesized by hydrothermal process from the amorphous hydrous titanium oxide precursors.The as-prepared products were characterized by X-ray powder diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The electrochemical behaviors of Li₄Ti₅O₁₂ electrode in conventional organic electrolyte and ionic liquid electrolyte were investigated by using cyclic voltammetry,galvanostatic charge-discharge and AC impedance techniques.The experimental results indicate that the as-prepared nanostructured Li₄Ti₅O₁₂,evaluated as anode material,exhibited good reversibility and cycle performance.It is expected to be a …

Synthesis Of High-Performance Lini1/3Co1/3Mn1/3O2 Cathode Materials Via Azeotropic Distillation Method, Sheng-An Xia, Li-Xia Yuan, Ze Yang, Zhao-Hui Wang, Yun-Hui Huang, Shuang Li, Wu-Xing Zhang, Ya-Bin Meng, Wei-Gong Zheng

Journal of Electrochemistry

Layered LiNi_1/3Co_1/3Mn_1/3O₂ is one of the most promising alternative materials for LiCoO₂ in lithium ion batteries due to its low cost,large capacity and excellent cyclability.In this paper,LiNi_1/3Co_1/3Mn_1/3O₂ was synthesized via azeotropic distillation method with isobutyl alcohol as an azeotropic agent.The structure and surface morphology were characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM),respectively.The as-prepared LiNi_1/3Co_1/3Mn_1/3O₂ shows a layered α-NaFeO₂ structure;the particles are small and uniformly distributed.As compared with the sample prepared by traditional method,the present cathode material …

Electrochemical Behavior Of Co-Ru Composite In Alkaline Solution, Su-Mei Yao, Guo-Chun Li, Xue-Ping Gao

Journal of Electrochemistry

The electrochemical properties of Ru doped cobalt hydroxides synthesized via homogeneous chemical co-precipitation were investigated in 6 mol·L^-1 KOH solution by galvanostatic charge-discharge process and cyclic voltammetry(CV).It is demonstrated that Ru doped cobalt hydroxides exhibited good capacitive characteristic and high specific capacitance.The sample with a Co/Ru molar ratio of 8 /1 shows the optimized electrochemical performance,including capacitive property and discharge capacity.The microstructure and morphology of the obtained Ru doped hydroxides were characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM).The amorphous structure of ruthenium dioxide nanoparticles and single-crystal structure of Co(OH)₂ platelets were confirmed.Based on a structure analysis and …

Electrocatalytic Reduction Of L-Cystine At Pb/Nanotio2 Film Electrode, Dao-Bao Chu, Feng Wang, Ying Xiao, Xue-Jiao Zhang

Journal of Electrochemistry

The nanoporous Ti-based TiO₂ films electrodes modified with Pb particles(Pb/nanoTiO₂) were prepared by using anodization and potentiostatic electro-deposition.The optimum deposition conditions were determined by comparing with various deposition potentials and time.The SEM analyses indicated that the TiO₂ films were homogeneous nanoporous structure,and the Pb particles well dispersed on the TiO₂ films.The L-cystine electrocatalytic activity reduction on the Pb/nanoTiO₂ film electrodes was investigated by cyclic voltammetry and Chronoamperometric curves.The results showed that this type of the electrode posseses high acticity and stability.

Preparation And Characterization Of Sulfur/Mesoprous Carbon Composite Cathodes, Wen-Hua Zhang, Yao Chen, Xin-Ping Ai, Yu-Liang Cao

Journal of Electrochemistry

A sulfur/mesoporous carbon composite was prepared by thermally treating a mixture of sublimed sulfur and mesoporous carbon. The microstructure of the mesoporous carbon was characterized by BET analysis and X-ray diffraction(XRD). The electrochemical performance of the S/C composite as cathode materials was evaluated by the galvanostatic method. The results confirmed that the mesoporous carbon could not only greatly enhance the electrochemical activity of sulfur electrode, but also effectively confine the diffusion of dissolved polysulfides in organic electrolyte. As a result,the S/C composites showed high capacity, good cycle performance and excellent rate capability. The specific capacity of the S/C composite was …

The Synthesise Of Electron-Conducting Redox Hydrogel And Its Application In Microbial Fuel Cell, Kai-Peng Wang, Sheng-Li Chen

Journal of Electrochemistry

Efficient electron transfer between the microbe and the anode is key for the electricity generation in Microbial fuel cell(MFC).Through the modification of anode,the rate of electron transfer can be accelerated,therefore the performance of MFC can be enhanced.In this paper,we report the synthesis of a type of electronconducting and bio-compatible redox hydrogel and its application.The hydrogel consists of poly(4-vinylpyridine) as backbone and neutral red as the redox center.By immobiliazing neutral red on the backbone through covalent bond,the secondary contamination due to the soluble redox mediator to external environment can be prevented.MFCs using the hydrogel-modified carbon anode significantly exhibit shorter acclimation period,and …

Electrochemical Properties Of Ni(Oh)2 Doped By Nio, Fei-Biao Chen, Bo-Rong Wu, Wei-Feng An, Zhao-Jun Yang, Feng Wu, Shi Chen

Journal of Electrochemistry

The Ni(OH)₂ cathode material of MH/Ni was doped by NiO,which behaves as a capacitor and can improve the charge-discharge rate capacity of Ni(OH)₂.The electrochemical properties of Ni(OH)₂ was characterized by charge-discharge curves and cyclic voltammetry.The results showed that the material had the best discharge property when doped by 5% NiO,and the discharge specific capacity could reach 310.1 mAh/g at 0.2 C rate and remianed 79.5% at 3 C rate.The difference oxidation and reduction potentials between the of the battery was 164 mV when the Ni(OH)₂ was doped by 5% NiO,which showed a good cyclic property.

Electrosynthesis Of P-Aminobenzenearsenic Acid, Chun-An Ma, Qin-An Zheng, Qiang Zhou, Ying-Hua Xu

Journal of Electrochemistry

The electrochemical reduction of p-nitrophenyl arsonit acid to p-aminobenzenearsenic acid was studied using controlled-current electrolysis.The results showed that the yield of p-aminobenzenearsenic acid was determinated by the following factors:the concentrations of sulphuric acid,the amount of additive,temperature and the concentrations of p-nitrophenyl arsenic acid.The optimum electrolytic conditions were obtained to be is 10% H₂SO₄,1% NaCl,80 ℃,25 g/350 mL p-nitrophenyl arsenic acid and 10 A·dm^-2.The yield of arsanilic acid could be reached 64.7% under the optimum electrolytic conditions.

Cobalt-Doped Todorokite Prepared By Refluxing At Atmospheric Pressure As Lithium-Ion Battery Cathode, Rui-Qi Li, Chun-Hua Song, Chao Xu, Li-Xing Tu, Guo-Hong Qiu, Fan Liu

Journal of Electrochemistry

Cobalt-doped todorokites were prepared by refluxing at atmospheric pressure,and then charactered by X-ray diffraction(XRD),thermogravimetry(TG) and the analysis of chemical compositions.These measurements showed that all of the refluxing products were single phase of todorokites and the structure formulas were Mg_xCo_yMnO_z·nH₂O,where 0.18 ≤ x ≤ 0.22,0 ≤ y ≤ 0.24,2.10 ≤ z ≤ 2.53,and 0.35 ≤ n ≤0.73.The electrochemical characteristics of cobalt-doped todorokites were examined as lithium insertion hosts for cathodes in rechargeable lithium batteries.The first discharge capacity of undoped todorokite electrode was 211 mAh/g and the discharge capacity became 37 mAh/g after 30 …

Fabrication And Characterization Of The Ni-Scsz Composite Anodes With A Lscm-Ceo2 Catalyst Layer In Thin Film Sofc, Yun-Yun Wang, Bo Huang, Xin-Jian Zhu, Wan-Qi Hu, Qing-Chun Yu

Journal of Electrochemistry

Solid oxide full cell(SOFC) running directly on hydrocarbon fuels has attracted much attention in recent years. In this paper, a dual-layer structure anode was fabricated by tape casting and screen printing method. The addition of a LSCM-CeO₂ catalyst layer to the supported anode surface yielded better performance in ethanol fuel. The maximum power density reached 710 and 669 mW/cm² at 850 ℃ running on hydrogen gas steam and ethanol steam,respectively. No significant degradation in performance has been observed after 216 h of cell testing when the Ni-ScSZ13 anode was exposed to the ethanol steam at 700 ℃. Very …

2010 Spring Engr333 Project Assignment, Matthew K. Heun

ENGR 333

The Spring 2010 ENGR333 project assessed options for the design of a redundant data center for the Calvin campus.

I asked the students “What would it take to build a redundant data center at Calvin that is 30% more energy efficient than the existing data center?”

Note: Because I was on sabbatical in Fall 2009, ENGR333 was moved to Spring 2010.

Customer

The customer for this project was Calvin’s VP for finance Henry DeVries.

The Value Of Concentrating Solar Power And Thermal Energy Storage, Ramteen Sioshansi, Paul Denholm

Publications (E)

This paper examines the value of concentrating solar power (CSP) and thermal energy storage (TES) in four regions in the southwestern United States. Our analysis shows that TES can increase the value of CSP by allowing more thermal energy from a CSP plant’s solar field to be used, by allowing a CSP plant to accommodate a larger solar field, and by allowing CSP generation to be shifted to hours with higher energy prices. We analyze the sensitivity of CSP value to a number of factors, including the optimization period, price and solar forecasting, ancillary service sales, capacity value and dry …

Doe Request For Information (Rfi) De-Foa-0000153 Pv Manufacturing Initiative: Summary Report, National Renewable Energy Laboratory

Publications (E)

Clean Cities hosts a collection of tools on the exploring concepts for a “PV Manufacturing Initiative” to facilitate the development of a strong photovoltaic (PV) manufacturing industry in the United States. As an integral part this effort, and to inform the creation of a new funding opportunity in this area, DOE sought feedback from the PV industry.

This document summarizes the results of the PV Manufacturing Request for Information (RFI), DE-FOA-0000153. (See Attachment 1.) The RFI was posted on http://www.grants.gov on 4 September 2009 and the NREL Web site on 9 September 2009. Respondents were asked to submit RFI inputs …

Ab Initio Simulations Of Hydrogen And Lithium Adsorption On Silicene, Tim H. Osborn

Browse all Theses and Dissertations

The energies and temperature-dependent dynamics of hydrogen and lithium chemisorption on a silicon nanosheet, called silicene, were studied using density functional theory and molecular-dynamics (MD) simulations. Silicene has a buckled honeycomb structure, and has been fabricated as suspended monolayer sheets and nanoribbons in recent experiments. We calculated the adsorption energies of hydrogen and lithium on silicene for different adsorption ratios between 3.1% and 100%. The studies will clarify the characteristics of these novel and promising nanomaterials, and pave the way for their applications.

For Hydrogen, the adsorption energy had a maximum of 3.01 eV/H for complete hydrogenation, and decreased by …

Fabrication Of Zinc Oxide Thin Films For Renewable Energy And Sensor Applications, Theresa Y. Hill

Browse all Theses and Dissertations

Progress in commercializing renewable energy technologies is being advanced by developments in Zinc Oxide material science. The photovoltaic cell, for example, generates electricity by receiving solar energy into the cell, generating electrons, and simultaneously transporting electrical charge out of the cell. Metals are capable of removing electrical charge but block transmission of sunshine. Glass and plastics are capable of transmitting sunshine but block the removal of electrical charge. Therefore an exterior layer that is both optically transparent and electrically conductive is desirable. Transparent conductive oxides (TCOs) are the ideal material for such applications since they are capable of both functions. …

Sulfur-Tolerant Catalyst For The Solid Oxide Fuel Cell, Bozeman Joe Frank Iii

Browse all Theses and Dissertations

JP-8 fuel is easily accessible, transportable, and has hydrogen content essential to solid oxide fuel cell (SOFC) operation. However, this syngas has sulfur content which results in a poisonous hydrogen sulfide that degrades electrochemical activity and causes complete SOFC failure in some cases. The goal is to synthesize and verify a cost-effective, catalyst supported on cerium oxide that either stabilizes ionic conductivity in the presence of hydrogen sulfide and/or is highly sulfur-resistant. After thorough computational analysis, it was concluded that the platinum-copper skin catalyst was the most cost-effective, sulfur-resistant catalyst. Experimental synthesis of copper, platinum, and platinum-copper skin catalysts supported …

The Role Of Energy Storage With Renewable Electricity Generation, Paul Denholm, Erik Ela, Brendan Kirby, Michael Milligan

Publications (E)

Renewable energy sources, such as wind and solar, have vast potential to reduce dependence on fossil fuels and greenhouse gas emissions in the electric sector. Climate change concerns, state initiatives including renewable portfolio standards, and consumer efforts are resulting in increased deployments of both technologies. Both solar photovoltaics (PV) and wind energy have variable and uncertain (sometimes referred to as “intermittent”) output, which are unlike the dispatchable sources used for the majority of electricity generation in the United States. The variability of these sources has led to concerns regarding the reliability of an electric grid that derives a large fraction …

2008 Solar Technologies Market Report, U.S. Department Of Energy

Publications (E)

This report focuses on the U.S. solar electricity market, including photovoltaic (PV) and concentrating solar power (CSP) technologies. The report provides an overview of global and U.S. installation trends. It also presents production and shipment data, material and supply chain issues, and solar industry employment trends. It also presents cost, price, and performance trends; and discusses policy and market drivers such as recently passed federal legislation, state and local policies, and developments in project financing. The final chapter provides data on private investment trends and near-term market forecasts.

Analysis Of Hybrid Hydrogen Systems: Final Report, J. Dean, R. Braun, D. Munoz, M. Penev, C. Kinchin

Publications (E)

This project examined biomass pathways for hydrogen production and how they can be hybridized to support renewable electricity generation. The project considered many potential hybrid systems before narrowing the focus to two. The systems were studied in detail for process feasibility and economic performance. The best-performing system was estimated to produce hydrogen at a cost ($1.67/kg) within range of the Department of Energy target for central biomass-derived hydrogen production, while also providing value-added energy services to the electric grid.

Nrel: A Year In Clean Energy Innovations: A Review Of Nrel's Feature Stories, National Renewable Energy Laboratory

Publications (E)

The National Renewable Energy Laboratory (NREL) is the nation’s primary laboratory for renewable energy and energy efficiency research and development.

NREL’s mission and strategy are focused on advancing the U.S. Department of Energy’s and our nation’s energy goals. The laboratory’s scientists and researchers support critical market objectives to accelerate research from scientific innovations to market-viable alternative energy solutions. At the core of this strategic direction are NREL’s research and technology development competencies. These areas span from understanding renewable resources for energy, to the conversion of these resources to renewable electricity and fuels, and ultimately to the use of renewable electricity …

Wind Powering America: Fy09 Activities Summary, National Renewable Energy Laboratory

Publications (E)

The Wind Powering America FY09 Activities Summary reflects the accomplishments of state Wind Working Groups, WPA programs at the National Renewable Energy Laboratory, and partner organizations.

Exercise Power Grid Display And Web Interface, Alexander (Alex) Chernetz

Computer Engineering

The 2008-2009 expansion of the Recreation Center at Cal Poly includes three new rooms with cardiovascular fitness equipment. As part of its ongoing commitment to sustainable development, the new machines connect to the main power grid and generate power during a workout. This document explains the process of quantifying and expressing the power generated using two interfaces: an autonomous display designed for a television with a text size and amount of detail adaptable to multiple television sizes and viewing distances, and an interactive, more detailed Web interface accessible with any Java-capable computer system or browser.

Reflective Optics Cpv Panels Enabling Large Scale, Reliable Generation Of Solar Energy Cost Competitive With Fossil Fuels, S. Horne, M. Mcdonald, N. Hartsoch, K. Desy

Publications (E)

The objective of this 18 month subcontract was the improvement of reflective optics CPV panels to enable the large-scale, reliable production of solar electricity to meet SAI-established LCOE targets, and ultimately provide a path to solar power at parity with or better than the cost of energy generated utilizing fossil fuels. To this end, SolFocus has completed this subcontract with great success as evidenced by the end results of a CPV panel with conversion efficiencies greater than the targeted 22% and manufacturing capabilities with a run rate capacity far exceeding the milestone benchmark >3MW.

Wind Energy And Power System Operations: A Review Of Wind Integration Studies To Date, Jennifer Decesaro, Kevin Porter

Publications (E)

This paper provides an overview of the challenges associated with wind integration and summarizes the findings of the wind integration studies conducted over the course of the past five years. We begin with an overview of the approximate time frames used in grid operations. We then describe how wind integration studies are conducted, discuss the results on wind integration costs and grid impacts from these grid integration studies, and assess some of the grid planning and operation changes that may be necessary to incorporate higher levels of wind generation. We close with several conclusions.

Indirect Electrosynthesis Of Double Aldehyde Starch Using Pb-(Bro3-/Br-) As Electro-Catalytic Mediator, Ni-Na Chen, Ri-Yao Chen, Xi Zheng, Xiao Chen, Zhen Chen

Journal of Electrochemistry

In this paper,Nafion membrane was used as the separator in the electrolysis cell to indirectly electro-generating the double aldehyde starch(DAS) with BrO₃^-/Br^-as a redox mediator and Pb as an anode.Effects of temperature,concentration of sulfuric acid and starch on the electro-oxidation of DAS were discussed.The steady state polarization curves were obtained.The experiment results showed that the current efficiency was over 50% when the electrolysis current density was 15mA/ cm².

Progresses In Electrocatalysis Of Nanomaterials—Tuning The Surface Structure And Property Of Electrocatalysts, Yan-Xia Jiang, Na Tian, Zhi-You Zhou, Sheng-Pei Chen, Shi-Gang Sun

Journal of Electrochemistry

The property of an electrocatalyst depends strongly on its surface structure.The study of surface structure-catalytic functionality is the base of design and preparation of electrocatalysts of high activity,high stability and high selectivity at microstructure level.In this paper,based mainly on our results concering hydrogen and oxygen adsorption-desorption,ethylene glycol oxidation and CO₂ reduction,the research progresses in tuning the surface structure and property of electrocatalysts are summarized.This paper overviews firstly the cyclic voltammetric characteristics,electrocatalytic properties of platinum single crystal planes lying on different crystallographic zones of the unit stereographic triangle of face-centered cubic(fcc) metals.Next,the innovation of electrochemical methods to control the surface …