Behavior Prediction of Metal Hydride Electrodes in Operation Used in Alkaline Batteries

J. E. THOMAS; E. B. CASTRO; S. G. REAL; A. VISINTIN

INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

Elsevier Science

Lugar: NY Vol. 33; Año: 2008 vol. 33 p. 3493 - 3495

0360-3199

Metallic alloys of multicomponents and multiphases are used at present in electrodes for nickel metal hydride rechargeable batteries due to their high capacity and good kinetics. The influence of structural properties of the electrode, such as porosity, are evaluated in terms of a physicochemical model in order to optimize the design of new electrodes. In the electrodes prepared with carbon, PTFE and AB5-type alloy, the influence of compaction pressure, on the discharge response of the electrodes was analyzed. An improvement in discharge performance has been observed, as the pressure of compaction is diminished, coming to a structural compromise of the electrode at low pressures. The simulation of the discharge curves in terms of a model based on the classic theory of porous flooded electrodes, predicts an enhancement in the discharge time associated with an increase in the porosity of the electrode as a consequence of the decrease of the compaction pressure.