Литиевые электрохимические системы

The influence of the composition, the thickness and the surface morphology of Li3V2(PO4)3 or Li4Ti5O12 based electrode composites with carbon nanomaterial and polyvinylidene fluoride on their electrochemical performance was examined. The thickness and the surface morphology of the electrodes were jointly controlled by rolling with different gaps and monitored using 3D laser microscopy and scanning electron microscopy.

The use of solid polymer electrolytes is a novel and promising approach for enhancing the safety of lithium-ion and sodium-ion batteries. A number of publications on manufacturing electrolytes with lithium-ion and sodium-ion conductivity based on Nafion-like polymers have appeared in recent decade. The present mini-review analyses various methods of the synthesis of such electrolytes and their properties, as well as the information on laboratory lithium-ion and sodium-ion batteries using such electrolytes.

The protective properties of the coating applied to the surface of lithium-manganese spinel (LiMn2O4), using the eutectic composition of Li2O : B2O3 = 47 : 53 (wt.) with the melting point of 650°C, were studied. The content of the eutectic lithium borate varied from 1% to 10%. The electrochemical behavior of the obtained materials in the cathode half-cells of lithium-ion battery was studied at room temperature.

An approach for constructing mathematical models of the current dependence of the capacity of electrode materials is proposed. The approach involves analyzing the probabilities of favorable and unfavorable events occurring on the elements of electrical equivalent circuits that can be used to model the electrode. Several probabilistic models that correspond to different combinations of a capacitor, a Warburg element and a constant phase element in an electrical circuit are proposed.

Nowadays, the active search for an anode material, which can be used in lithium-ion current sources, takes place. The potential anode materials are transition metal oxides (SnO₂, NiO and others). In this work, submicron NiO powder was obtained using the thermal decomposition of Ni(CH₃COO)₂⋅4H₂O. Besides, a NiO/C composite anode was fabricated and its behavior in the anode half-cell of lithium-ion current source was studied during multiple cycling.

Compositions of ultrafine Si and C particles are promising anode materials for lithium-ion power sources with improved energy characteristics. In the work, samples of lithium-ion power sources with an anode made of ultrafine SiC fibers, as well as mixtures of SiC fibers with graphite (C/SiC) and electrolytically deposited submicron silicon fibers (C/Si/SiC) were fabricated and studied for energy characteristics.

The effect of the structure and the specific surface area of carbon materials, contained in positive electrodes, on the peculiarities of cycling of lithium-sulfur cells (the depth of electrochemical reduction of sulfur and lithium polysulfides, the changes in capacity and Coulomb efficiency of cycling) was studied.