LECLANCHE CELL INVESTIGATIONS - PART II - ZINC POTENTIAL AS A TOOL FOR STUDYING INTERMITTENT DISCHARGE

R20 sized Leclanche cells containing EMD and traditional or ZnCl2 elec trolyte have been discharged through 4 Omega for 15, 30 and 60 min/day . Measurement of recuperated zinc electrode potential against a precis ely-located KCl bridge/SCE reference electrode assembly has enabled th e three major stages of discharge in traditional electrolyte to be dem onstrated in a cell for the first time. Reasonable correspondence betw een the discharge data and calculations, based on the positive active mixture composition, have confirmed the overall discharge reactions ta king place in stages 1 and 2. In ZnCl2 electrolyte, zinc potential dec reased more rapidly than would have been expected for a discharge prod uct of ZnCl2. 4Zn(OH)(2). H2O. The experimental behaviour could be exp lained if this product which has a layer structure, absorbed additiona l ZnCl2 and possibly H2O between the layers. The potential of the EMD/ H insertion electrode confirmed data obtained previously on another EM D so the large decrease of potential with H insertion is again ascribe d to independent mobility of inserted protons and electrons. (C) 1998 Elsevier Science Ltd. All rights reserved.