A route for the preparation of binder-free sulfur-carbon cathodes is developed for lithium sulfur batteries. The method is based on the impregnation of elemental sulfur into the micropores of activated carbon fibers. These electrodes demonstrate good electrochemical performance at high current density attributed to the uniform dispersion of sulfur inside the carbon fiber.

Document VersionPublisher's PDF, also known as Version of Record (includes final page, issue and volume numbers) Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Platinum catalysts are involved in a vast variety of redox reactions, and O 2 reduction is one of the most important of them. Therefore, considerable efforts are undertaken by electrochemists to understand the fundamental aspects of Pt catalysts and to improve the properties of applied catalytic systems in general. The fundamental relevance of Pt catalytic properties has become even more important because carbon-supported Pt catalysts have so far been the best choice for the oxygen reduction at the cathode of low-temperature polymer electrolyte membrane fuel cells ͑PEMFCs͒. 1The oxygen reduction reaction ͑ORR͒ on Pt surfaces has been widely studied in electrochemistry, but the details of the mechanism remain elusive. The overall ORR is a multistep process involving four electron transfers during which bonds are broken and formed. It is still not clear whether the process starts from the oxygen molecule dissociation on Pt electrodes, this being followed by electron and proton transfer, or whether the first reduction step happens before O-O bond cleavage. Damjanovic proposed that the first step is an electron transfer to the O 2 moleculeThis step is rate-determining and is either accompanied by or followed by a fast proton transfer. A theoretical study by Sidik et al. has proven the first electron transfer to be rate-determining on dual adsorption sites. Proton transfer is involved in this step, because the electron affinity of the reactant complex is increased significantly by t...

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Si electrodes are the most important high capacity substitutes of Li metal and carbon anodes in high energy density Li ion batteries, including those based on sulfur or air cathodes. In this study we examined amorphous columnar structure silicon film anodes prepared by sputtering in rechargeable Li ion battery prototypes based on TiS 2 cathodes. The choice of this cathode material enabled focusing on the examination of pre-lithiated Si films as anode candidates in alkyl carbonate electrolyte solutions. The effectiveness of fluoro-ethylene carbonate (FEC) as a co-solvent in alkyl carbonates/LiPF 6 solutions for good performance of silicon anodes was exhibited. Hundreds of cycles were demonstrated in full Li ion cells containing these components. The columnar morphology of these anodes is retained after 1000 cycles. Their surface chemistry, measured by EDS and XPS is discussed. The results of this work encourage further R&D efforts toward the use of amorphous silicon films as anodes in advanced rechargeable Li batteries.