ISSN 1608-4039 (Print)
ISSN 1680-9505 (Online)

Литиевые электрохимические системы

The effect of surface capacity of positive electrodes on cycle life of lithium-sulfur batteries

The effect of sulfur content in positive electrodes (the surface capacity of sulfur electrodes) on the characteristics (such as the depth of sulfur electrochemical reduction, changes in capacitance and Coulomb efficiency during cycle life) of lithium-sulfur cells with electrolytes based on sulfolane was studied. It was shown that the reason for the capacitance decrease of the lithium-sulfur cells at the early stage of its cycle life is the displacement of sulfur of the porous positive electrode from the rear regions into the front ones.

Study of the reversible electrochemical insertion of lithium into boron

The reversible insertion of lithium into electrodes based on amorphous boron has been studied. The reversible capacity upon the lithium insertion has been found to be about 750 mA⋅h/g. The most efficient in terms of specific capacity are the electrodes containing graphene as a conductive additive.

The chemical current sources with a magnesium anode: Electrode materials and their properties

The article is devoted to the study of the possibility of creating chemical current sources with a magnesium anode. The work presents the continuation of the analysis of conventional current sources with high specific characteristics. The article describes the types of cathode-active substances that have potential possibility in making chemical current sources with a magnesium anode or an anode based on magnesium intermetallic compounds.

Lithium-ionic batteries: the modern state, problems, and outlook

A modern state of developments of lithium-ion batteries, as well as their main problems and the directions of their advancing are reviewed.

Comparative examination of LiyNixCo1-xO2 materials for lithium-ion battery cathodes

A number of LiyNixCo1-xO2 compounds were synthesised by means of solid-state annealing. The synthesis conditions (the raw components, temperature, duration) were optimized so that phases with y > 0.97 were obtained suitable for making positive electrodes for lithium-ionic batteries. The charge-discharge characteristics of such LiyNixCo1-xO2. electrodes were studied.

Effect of synthesis conditions on electrochemical, electrophysical and structural characteristics of lithium cobalt oxide

The processes of thermodestruction of lithium and cobalt oxides and their mixtures have been studied. The studies using the IR-spectroscopy as well thermogravimetric analysis showed, that during the initial stage of heating the mixtures of lithium and cobalt acetates the double salts form, and only then their thermodestruction proceeds.

Electrochemical behavior of boron- and cadmium-doped carbon fibers

With the aid of chronopotentiometry, voltammetry, and potentiostatic closure, the electrochemical characteristics of lithium intercalation to polyacrylonitrile carbon fiber was determined, namely, the capacitance, kinetic currents, lithium diffusion coefficient, autocharge currents. The study was made at 298 К in 1 M solutions of LiClO4 in some mixed organic solvents (propylene carbonate – dimethoxyethane 7:3, propylene carbonate – diethyl carbonate 3:1).

New lithium conducting polymer electrolytes for power sources

The main roads of development in industrially useful solid polymer electrolytes (SPEs) are briefly reviewed. New SPEs based on acrylonitrile copolymers PBAN and PAN and lithium salts LiAsF6, LiCF3SO3, LiCIO4 have been obtained. The limits of salts solubility in polymer matrix PBAN were established. Ion solvation and ion association processes have been studied by IR spectroscopy. Conducting properties of SPEs were measured at 20-100°C.

Research of solid-state short-circuit system Li/polymeric composite of PAN for CSC

The researches of behaviour of electrochemical systems organized by a method of direct contact of the Li-anode and a polymeric composite, including co-polymer polyacrylonitrile and organic semiconductor representing salt of thiopyrily with ClO4- and SnCl62- anions are carried out. The basic electrochemical parameters of researched systems are determined.

Lithium-modified manganese oxides as materials for the positive electrode of the lithium batteiy

New phases in the Li2O-MnO2 system were obtained, capable of introducing lithium electrochemically at potentials about 3 V and reversibly. They possess a stable capacity on the level 70-80 mA·hour/g. Due to their low cost, simplicity of synthesis, and high cycling ability, the oxides synthesized show promise as a cathodic material for lithium-ionic batteries.