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


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Electrophysical properties of non-stoichiometric lithium-iron magnesium-substituted spinels

Samples having the chemical formula Li0.5 Fe2.5 – x MgxO4 (0 ? x ? 1) were prepared by the standard ceramic method. The parts of the dielectric constant ?', ?'' and A.C. conductivity ?(?) are measured at different frequencies from 10 – 2 to 105 Hz in the room temperature and different cooling velocity, and then the dielectric loss tangent tg ? was calculated. The sample with x = 0.1 what was cooled quickly showed the greatest values of ?0 as compared with the other samples.

Lithium rechargeable work in the systems with polymer electrolytes based on C-PVC and PVDE

Electrochemical behavior of Li in the systems with PE based on polymers of chlorinated polyvinylchloride and polyvinylidene fluoride were investigated by the method of cyclic voltammetry and galvanostatic cycling. Potentiodynamic investigations have shown that on lithium electrode even in the systems with polymer electrolyte the high current densities up to 5 mA/cm2 are realized. Influence of polymer electrolyte composition on the properties of the interface Li/electrolyte and rechargeable work of lithium electrode has been shown.

Catalytic composition and fuel influence on anodic processes characteristics of solid polymer electrolyte fuel cells

It was studied an influence of prior carbon treatment (temperature and gas conditions, mass content of waterproofing agent) on activity of platinum catalyst, synthesized on disperse carbon carrier. It was shown that characteristics of anodic processes depend on quantity of solid polymer electrolyte in catalytic composition. Optimal content of ion exchange polymer under varied degree of carbon carrier waterproofing (used for synthesis of platinum catalyst) is not equal.

Self-discharge dynamics and accelerated test approach for state-of-charge forecast for lithium cells BR2325

There were investigated the self-discharge dynamics in two homogeneous groups («A» and «B») of the coin lithium cells ВR2325 on the basis of superstoichiometric fluorocarbon CF1.20, selected from the uniform experimental batch of 10000 pieces. The reason of two different groups («A» and «B») appearance through 3–6 months of storage is connected with the origin of hydrogen fluoride in cathodes of group «A» cells, which will be derivated at auto catalytic hydrolysis of C-F-bonds by a moisture tracers (0.1–0.5%).

Iron disulfide is promising positive electrode material for lithium power battery

Comparative characteristic of natural and synthesized iron disulfide has been carried out. Physical, chemical and macrostructure characteristics of pyrite powders have been shown. By the methods of cyclic Vtammetry the electrochemical properties of FeS2 – based cathodes have been investigated in non-aqueous liquid (1М LiClO4; PC+DME) and polymer (CPVC; 1М LiClO4; PC) electrolytes.

Some trends in improvement of cathode materials for lithium-ionic batteries

Major trends in cathode active material development for lithium-ion batteries have been reviewed. Statistics on all publications in «Journal of Power Sources» (from 03.2006 till 04.2007) is summarized in order to point out that the main effort in secondary batteries development is concentrated on lithium-ion batteries, especially on positive electrode study. Based on these publications the main routes for LiCoO2 modification as well as for novel materials research have been reviewed.

Influence of structural parameters of lead-acid batteries on their service characteristics

The effect of new kind of the separator, with the glassmat on the positive plate, which pressing the active mass, and new alloys for positive grid on efficiency of service characteristics (starting capacity, the electrolyte level changing under the charging and discharging) was investigated.

A discharge equation of alkaline accumulators. activation-ohmic polarization

It is shown, that activation-ohmic items in empirical equations by Shepherd, Khaskina-Danilenko, Shepherd-Dasoyan, Romanov is abnormally describe of activation-ohmic processes at the discharge of accumulators a direct current. New expression U = RI + A ln(BI + 1) matching is offered to experimental data.

A carbonic material of vegetal raw materials for supercapacitor electrodes

Energy and power characteristics of supercapacitors with aqueous electrolyte and electrodes based on a carbonic material obtained of vegetal raw materials are investigated. Conditions for carbonization of the considered kinds of raw materials as well as a technology of the activation of the carbonized materials are established. It is shown that the activated materials prepared of corn smut and corn stigmas have high energy and power characteristics.

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