никель-кадмиевый аккумулятор

The development of nickel-cadmium batteries with high energy capacious electrodes is described. Selection and development of technology of manufacturing nickel-oxide electrodes based on nickel-plated carbon and graphite felt materials are considered. Discharge characteristics of the electrodes are analysed.

Approach to the choice of charge termination criterion of nickel-cadmium accumulators forming cycles is described. The results of accumulators' physical models forming, using chosen criterion are represented. The research shows the effectiveness of prolonged – before voltage regulation – charges during nickel-cadmium accumulators capacity forming due to the considerable decrease in the number of charge-discharge forming cycles and improvement of their discharge characteristics.

Comparison of asymmetric current parameters influence on nickel-cadmium accumulators forming time is performed. According to the results of capacity forming of NKM-22 accumulators with thin pressed cadmium and metal-ceramic electrodes, the perspective of application of asymmetric current with parameters chosen during experiments and used in this paper is established. Waveforms giving the biggest increase of capacity comply with the most economical parameters defined om models during experiments. In particular, application of asymmetric current with such parameters for NKM-22 accumulators forming gave 11% increase of discharge capacity compared with direct current forming.

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.

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. In particular, application of asymmetric current with such parameters in the process of NKPLHC-0,5 accumulators formation resulted in increase of discharge capacity, compared with formation by direct current, by 16%.

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. The electrochemical tests have shown that the mockup batteries with newly-developed nickel oxide electrodes based on nickelized carbon/graphite felt have surpassed all requirements of the international standard IEC 62259:2007.