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Ogniwa litowo-jonowe wysokiej mocy : przegląd materiałów katodowych

Urbanek K.

Wiadomości Chemiczne

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2018

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[Z] 72, 5-6

265--278

EN

Due to lack of practical energy sources – ones that are ecological, economic, portable and capable of being regenerated – storage is necessary in modern world for many areas of life to which people became accustomed. Development of many devices requires convenient electric power sources, often providing high currents and voltages, capable of ensuring large amounts of energy in short time. New technologies of lithium-ion cell batteries are a promising solution to this problem – current technologies are frequently inadequate – however they still require massive workloads in research, development, implementation to industry, and then to consumer market. Because of advancement in this area and evergrowing group of people interested in it is imperative to render an overview of the situation and knowledge of this topic. This article presents a review of most intensely studied cathode materials capable of providing high power, viable paths of improvement and short description of most important features of lithium-ion cells along with issues requiring solutions.

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Structural, morphological and electrochemical characterization of electron beam deposited Li 1+xMn2O4 (x = 0, 0.05) thin films

Balaji S., Shanmugan S., Mutharasu D., Ramanathan K.

Materials Science Poland

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2010

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Vol. 28, No. 2

583--593

EN

Li1+xMn2O4 (x = 0, 0.05) powders were synthesized using the microwave assisted co-precipitation method. Materials were evaporated using an electron beam gun. Structural analyses of thin films coated over platinum substrates revealed their cubic structure. The lattice constant of Li1.05Mn2O4 thin film was found to be around 8.2475 A. The lattice constant of Li1.05Mn2O4 Powder was found to be 8.2488 A. Morphological properties of the coated films were studied by SEM and the obtained micrographs were analyzed using the Image-j software. The roughness and the porosity were observed to be higher for the samples containing an excess of Li. The thin films were subjected to electrochemical characterization in aqueous LiNO3 solution; cyclic voltammograms obtained for the samples revealed two sets of well defined redox peaks around 0.07 and 0.1 V in LiNO3 solution. The redox peaks in Li1.05Mn2O4 thin film samples had lower intensities than those of the stochiometric compound.

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Cycling behaviour of barium doped LiMn2O4 cathode materials for Li ion secondary batteries

Sahan H., Göktepe H., Patat S.

Materials Science Poland

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2010

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Vol. 28, No. 4

773--780

EN

In order to improve the cycling performance of LiMn2O4, the spinel phase LiMn2-xBaxO4 (x = 0.01, 0.02 and 0.05) compounds were fabricated by the glycine-nitrate method. The structures of the products were investigated by X-ray diffraction. Electrochemical studies were carried out using the Li|LiMn2O4 and Li|LiMn2-xBaxO4 cells. The capacity loss of Li|LiMn2O4 cell is about 15% after 30 cycles, whereas that for Ba doped spinel materials (x = 0.01, 0.02 and 0.05) are 7.5%, 3.5% and 1.8% respectively. The good capacity retention of LiMn2-xBaxO4 electrodes is attributed to stabilization of the spinel structure by Ba doping of Mn sites. Ba substituted spinals display better cycle performance in terms of cycle life compared with LiMn2O4.