Publications by authors named "Elena Markevich"

The development of advanced liquid electrolytes for high-voltage/high-energy rechargeable Li metal batteries is an important strategy to attain an effective protective surface film on both the Li metal anode and the high-voltage composite cathode. Herein, we report a study of two CF-substituted ethylene carbonates as components of the electrolyte solutions for Li metal|NCM811 cells. We evaluated trifluoromethyl ethylene carbonate (CF-EC) and trans-ditrifluoromethylethylene carbonate Di-(CF)-EC as cosolvents and additives to the electrolyte solutions.

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Lithium sulfur batteries are suitable for drones due to their high gravimetric energy density (2600 Wh/kg of sulfur). However, on the cathode side, high specific capacity with high sulfur loading (high areal capacity) is challenging due to the poor conductivity of sulfur. Shuttling of Li-sulfide species between the sulfur cathode and lithium anode also limits specific capacity.

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To date, lithium ion batteries are considered as a leading energy storage and conversion technology, ensuring a combination of high energy and power densities and prolonged cycle life. A critical point for elaboration of high energy density secondary Li batteries is the use of high specific capacity positive and negative electrodes. Among anode materials, Li metal anodes are considerably superior due to having the highest theoretical specific capacity (3860 mAh g) and lowest negative redox potential (-3.

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We report on the highly stable lithium metal|LiNiCoMnO (NCM 622) cells with practical electrodes' loading of 3.3 mA h g, which can undergo many hundreds of stable cycles, demonstrating high rate capability. A key issue was the use of fluoroethylene carbonate (FEC)-based electrolyte solutions (1 M LiPF in FEC/dimethyl carbonate).

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The effect of fluorinated ethylene carbonate (FEC) as a cosolvent in alkyl carbonates/LiPF6 on the cycling performance of high-voltage (5 V) cathodes for Li-ion batteries was investigated using electrochemical tools, X-ray photoelectron spectroscopy (XPS), and high-resolution scanning electron microscopy (HRSEM). An excellent cycling stability of LiCoPO4/Li, LiNi0.5Mn1.

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Incorporation of electron accepting units (oxadiazole) into the 2,5-thienylene conjugated chain leads to a significant improvement in the n-doping-undoping redox stability of the resulting polymer.

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Using molecular mechanics (MM3 force field)-based methodology, conformational dynamics have been studied for 1-azabicyclo[2.2.0]hexane, 1-azabicylo[3.

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