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


-

Kinetics of Oxygen Reduction Reaction on Cobalt Containing Systems with Low Platinum Content

High temperature method was used to synthesize PtCo/C catalysts on the basis of various precursors. It was shown using the RDE method that a catalytic system with low Pt content (5.0 wt.% Pt + 1.5 wt.% Со) synthesized on the basis of H2PtCl6 and Co phthalocyanine on carbon black ХС72 demonstrates the highest electrocatalytic activity due to the formation of highly dispersed Pt3Co alloy particles. This was confirmed by XPS studies.

Degradation of matrix electrolyte under Molten Carbonate Fuel Cell environment

The change in phase composition, dispersibility and morphology of ?-, ?- and ?-lithium aluminates, which are the components of molten carbonate fuel cell were investigated after long exposure in Li/KCO3 (62/38 vol.%) eutectic melt under H2, H2 + CO2 (20-mol.%) and 0.33 O2 + 0.67 CO2 atmospheres at 650°C. ?- , ?- , ?- aluminates and their mixtures were found to transform into ?-phase under oxidative atmosphere. Under reducing atmosphere both ?- and ?-phases always coexist.

Production of electrolytes based on LiPF6 and mixtures of carbonate estors by means of double exchange reactions

By the methods of isothermal solubility, 19F NMR spectroscopy and also by implementation of ab initio quantum – chemical calculations the kinetics is explored and thermodynamics of reactions of double exchange in the systems K(Na)RF6 – LiBF4 – propylene carbonate – dimethyl carbonate. A method is offered of receipt of electrolytes on the basis of LiРF6 and mixtures of carbonate ethers. An electrolyte successfully is tested in elements with the hard cathodes.

Thermostable membranes for fuel cells

Thermostable proton exchange membranes for fuel cells are overviewed. Three groups of the membrane are described: modified membranes based on perfluorosulfonic acid, alternative sulfated polymers and corresponding composite membranes, acid-alkali polymer membranes.

Advanced non-destructive methods for state-of-charge diagnostics of the industrial and pilot lithium coin cells

It was established one-, two and three-factor regression dependencies among discharge capacity С, short-circuit current I (SC), open circuit voltage U (OCV), internal resistance (Ri) and mass (m) for polynomials of a degree n(n = 1–4) in all sampling. The discharge capacity of ``fresh'' cell's forecasts a little bit better than after their long storage and magnitude of standard deviations for ``fresh'' CR2325 (2.5%) differ from ``old'' cells approximately twice (5.5%).

Discharge of alkaline batteries

It is shown that the correlations of Romanov and Shepherd–Dasoyan are equivalent under description of discharge curves of alkaline accumulators in the interval of discharge voltages from the beginning to 1 V and any ones used for the particular accumulators of discharge currents. However under low discharge voltages the correlation of Shepherd–Dasoyan describes the direction of discharge curve correctly while the correlation of Romanov gives false results.

Kinetics of processes in the lanthanum-based LiLaAl/LiClO4/MnO2, system at potentiodynamic cycling

In present work the lithium diffusion was investigated to LiAl- and MnO2-electrodes, modified by La. With this purpose Al and MnO2 was worked up by cathodiе incorporation method in aprotic organic solutions of sulfanilate lanthanum. The next cyclization of electrodes to lithium perchlorate solution was making in potentiodynamic conditions.

Mathematic simulation of current generating processes and analysis of porous electrode operating efficiency

With mathematical methods of description of macrokinetic processes in the volume of porous electrodes the investigation of influence of kinetic and structural characteristics of electrode-comprising materials to the process of current generation was performed. The nonuniformity of current generation distribution as well as the level of polarization loss are significantly determined by correlation of electric conduction values of solid phase components and electrolyte.

Criteria and mechanism of capacity and pseudocapacity charge accumulation in activated carbon in view of its nanoporous structure and electronic structure

The relation between porous structure, electronic properties of carbonaceous material and the capacitance of its interface with an electrolyte is discussed. The sizes of the pores in which the processes of capacitive and pseudocapacitive charge accumulation dominate are determined.

Behavior of Small Lithium-ion Batteries During Overcharge

Safety level of small commercial Lithium-Ion cells with LiCoO2 as cathode material during overcharge was investigated. Conditions and possible mechanism of autocatalytic rise of temperature and pressure inside the battery were discussed.

Pages