Sökning: "in-situ impedance spectroscopy"

Visar resultat 11 - 15 av 24 avhandlingar innehållade orden in-situ impedance spectroscopy.

  1. 11. Proton Conducting Ceramics; Synthesis, Characterization and Sample Cell Environments

    Författare :FRANCIS GACHAO KINYANJUI; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; perovskites; neutron diffraction; Rietveld refinements; BaSnO3; in-situ cell; deuteron position; proton conduction; BaZrO3;

    Sammanfattning : Acceptor doped Perovskite ceramics have been shown to exhibit high levels of protonic conduction in humid atmospheres. However significant grain boundary resistance and long sintering times required to achieve sufficient grain size growth has hindered their widespread application as electrolyzers, fuel cells and gas separation membranes. LÄS MER

  2. 12. Functional Oxide Materials exhibiting Ionic Conductivity for Future Energy Conversion Needs

    Författare :FRANCIS GACHAO KINYANJUI; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; neutron diffraction; perovskites; oxygen deficient perovskites; BaSnO3; Rietveld refinements; BaZrO3; in-situ cells; proton conduction; deuteron position; Ba3In2ZrO8;

    Sammanfattning : Fuel cells are electrochemical devices that transform the chemical energy in hydrogen and oxygen into electrical energy at high efficiencies and produce only water vapour emissions. Materials with the perovskite or fluorite structure types are commonly employed as the ion conducting ceramic electrolyte membranes in intermediate and high temperature fuel cells. LÄS MER

  3. 13. Transition Metal-Based Electrocatalysts for Alkaline Water Splitting and CO2 Reduction

    Författare :Zhen Qiu; Tomas Edvinsson; Kevin Sivula; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Alkaline water splitting; CO2 reduction; Electrocatalyst; In-situ Raman spectroscopy.; Kemi med inriktning mot materialkemi; Chemistry with specialization in Materials Chemistry;

    Sammanfattning : With excessive usage of fossil fuels and ever-increasing environmental issues, numerous efforts have been devoted to the development of renewable energies for the replacement of traditional fossil fuels to reduce greenhouse gas emission and realize the rapidly growing demand for global energy. Renewable energies, however, often show diurnal and seasonal variations in power output, forming a need for energy storage to meet people’s continuous energy supply. LÄS MER

  4. 14. Electrochemical Studies of Aging in Lithium-Ion Batteries

    Författare :Matilda Klett; Göran Lindbergh; Charles Delacourt; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; aging; EIS modeling; electrolyte characterization; graphite; hybrid electric vehicles; impedance spectroscopy; LiFePO4; Li-ion batteries;

    Sammanfattning : Lithium-ion batteries are today finding use in automobiles aiming at reducing fuel consumption and emissions within transportation. The requirements on batteries used in vehicles are high regarding performance and lifetime, and a better understanding of the interior processes that dictate energy and power capabilities is a key to strategic development. LÄS MER

  5. 15. Lithium Ion Conductive Membranes Based on Co-continuous Polymer Blends

    Författare :Anette Munch Elmér; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Polymerteknik; Polymer technology; biopolymers; conductivity measurements; in-situ UV-polymerisation; solution casting; poly methyl methacrylate ; vinylidene fluoride copolymers; poly ethylene carbonate-co-ethylene oxide methacrylate; PEG methacrylate macromonomers; heterogeneous polymer blends; polymer electrolyte membranes; lithium salt containing gels;

    Sammanfattning : There is a growing need for multifunctional polymeric materials for the development of several important energy conversion technologies. For example, the polymer electrolyte is a key component in lithium polymer batteries. The basic functions of this electrolyte are to efficiently conduct the lithium ions and physically separate the electrodes. LÄS MER