Alkaline batteries

Development of the effective ways of the activation of the anodes for water electrolysis

Electrochemical activity of anodes on the basis of a nickel mesh grid for water electrolysis is investigated. Activation of anodes was made by three ways:
1) chemical covering sulfur-containing compounds of nickel and iron;
2) immersing in solution Na2S2O3 + H2SO4 (till pH=3);
3) immersing in solution Na2S + H2SO4 (till pH=3).
The water solution 6M KOH was used as the electrolyte while the electrodes testing. Current density varied in a range from 1 to 600 mAJ cm2 at temperature 20, 50 and 70°C. The greatest electrochemical activity have anodes activated by the third method. The anode potential at current density 600 mA/cm2 and temperature 70°C is equal +0.57 V (concerning Hg/HgO – the comparison electrode).

Electrochemical activity of the cathodes with platinum or platinum-palladium electrocatalysts for alkaline water electrolysis

Electrochemical activity of cathodes with Pt or Pt-Pd-electrocatalysts was studied by voltammetry method under galvanostatic conditions. The dependence of the overvoltage of hydrogen evolution reaction on the logarithm of current density and on the test time of the cathode with Pt-Pd-electrocatalysts are defined. It is shown that the electrochemical activity of cathode with Pt-Pd-electrocatalyst is two times higher than with Pt-electrocatalyst at the hydrogen evolution reaction in 30% KOH solution at 90°C. As the temperature increases from 15 to 90° C the current density at 40 mV overvoltage at the cathode with Pt-Pd-electrocatalyst increases by 8 times. The test results with this cathode electrocatalyst in the laboratory electrolyzer at a current density of 400 mA/cm2 and 65° C temperature within 11 days of intermittent regime work confirm the overvoltage stability in time.

Tests of the sealed nickel-cadmium storage batteries for capacity safety during long-term storage after charging with direct and asymmetric currents

Comparative results of the tests of the sealed nickel-cadmium batteries for capacity safety during long-term storage after charging with direct and asymmetric currents are represented. Charging with asymmetric current was carried out in an accelerated manner at average value of the charging current equal to 0.8Crated. Charging with direct current was carried out at average value of the charging current equal to 0. lCrated in accordance with Technical Conditions. Tests prove that batteries acceleratedly charged with asymmetric current are compliant with technical conditions concerning capacity safety during long-time storage. Tests also prove discharge capacity advantage of batteries charged with asymmetric current after long storage, in comparison with batteries charged with direct current.

Automated rapid charge of the sealed nickel-cadmium storage batteries with asymmetric current, and its influence on the resource

The research results of the sealed nickel-cadmium storage batteries reliability at the rapid charge with asymmetric current are represented. In accordance with the reliability theory postulates, the experimental data of the resource test in the mode of the storage batteries 10NKGZ-1,8-1, 10NKGZ-3,5-l, 10NKGZ-4 cycling. The predicted resource gain in comparison with the direct current charge, while using the device of automated storage batteries charge with asymmetric current is confirmed, as well as decrease in the mode of the heating-up charge, and the fall-off in gas emission intensity.

Generalized model of capacitance from discharge current dependence in nickel-cadmium batteries

For nickel-cadmium batteries of stationary application, a global empiric correlation C(i) describing the dependency of released capacitance by the batteries at different discharge currents was suggested, which is true for batteries of any capacitance and any mode of discharge (H, M, L). The global correlation C(i) can be described by generalized Peukert's equation, Korovin-Skundin's equation, probability integral, and porous electrode equation with accuracy sufficient for practical application. This correlation is most easily described by the generalized Peukert's equation C=Cm/(1+(i/IC/2)3.6).

Temperature dependence of polarization and corrosion characteristics of different aluminum alloys in alkaline electrolyte

Aluminum is one of the most energy-intensive materials, which is the base for the air-aluminum electrochemical generators (AA ECG) with a specific energy of 300 W·h/kg. Such generators can be considered as a promising source of energy for electric vehicle due to their advantages such as high energy, the possibility of organizing a closed cycle of aluminum production and use of heat generated by the AA ECG for heating the interior of the electric vehicle. The operation of AA ECG is most effective when aluminum alloys with indium in an alkaline electrolyte (with the addition of tin salts as a corrosion inhibitor) are used. The subjects of temperature influence on the anodic dissolution and aluminum corrosion and maximum power density are still not enough studied. This article is devoted to the study of the temperature effect on the anodic dissolution of aluminum and its alloys at the maximum achievable current density.

Influence of additive in electrolytic production of zinc electrode on its electrical characteristics

We have studied the influence of brighteners used in zinc electroplating on the characteristics of zinc powder, which produced in the manufacture of electrolytic zinc electrode. Their effect was determine on the cathodic process, the nature of spongy zinc deposits, corrosion of the zinc electrode and capacity characteristics with intense discharge in a nickel-zinc accumulator.

Nonlinear structural model of the battery, research of processes of relaxation after charge

It is shown that the nonlinear structural model of the battery can be used for modeling the voltage relaxation processes after a charge of batteries. The solution obtained is valid for alkaline, acid and lithium-ion batteries. Comparison of solutions, with the experimental data for nickel-cadmium batteries, showed, that the relative error does not exceed 3%.