Щелочные аккумуляторы

It is shown by experiments that probability of thermal runway in nickel-cadmium batteries with sintered oxide-nickel electrodes is higher, than in the batteries with extruded and pasted electrodes. Besides, it is shown that the probability of thermal runaway decreases with decrease of battery capacitance.

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).

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.

The results of nickel-cadmium accumulators formation with asymmetric current, in the mode providing long life of the first cycle till the accumulator stress stops to grow, are represented. The possibility of using stress on the accumulator as criterion of charge completion is proved. Research shows efficiency of mode applying chosen criterion – consedirable decrease of charge-discharge cycles of formation while preserving given working characteristics.

It was shown by experiments for SAFT batteries of stationary application and medium rate of discharge, that empirical equations Korovin-Skundin's, Peukert's generalized equation, probability integral, porous electrode equation allow to describe the dependence capacitance C(f), given by nickel-cadmium batteries, from discharge current with the accuracy sufficient for practical needs (5-6%) on all the range of discharge currents.

Comparison of influence of asymmetric current parameters on nickel-cadmium accumulators formation process time is carried out. According to the results of capacity formation of accumulators types NKPLHC-0,5 with thin extruded electrodes, we established good perspective for application of asymmetric current with parameters chosen during experiments and applied in this paper. Current waveform which gave the biggest capacity increase, has long charging impulse and short, with wide range, discharge impulse.

A study of the porous structure and discharge characteristics of electrochemically impregnated nickel oxide electrodes based on nickel- ized graphitized felt«Voilocarb-22» is conducted. It is shown that the developed technology of nickel oxide electrodes fabrication that involves such operations as nickel plating of the substrate, electrochemical impregnation, electrode formation and pressing allows forming polydisperse structured electrode active material with pore sizes ranging from 0.01 pm to 100 pm.

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.

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.

Our test results of nickel-cadmium FKM mock-up batteries with metal-felt nickel-oxide electrodes are presented. The discharge characteristics of the tested mock-up batteries with nickel-oxide electrodes made on the carbon-graphite felt basis are shown to exceed virtually all relevant requirements of Russian Railway Industry Standards. The high cyclability of these batteries was established: reduction of the discharge capacity lower than the nominal value was observed after 3100 cycles.