Porosity and Pore-size Distribution of Sintered Nickel Plaque for Battery by Slurry Technique

Abstract

It has been found that the porosity of the sintered nickel plaque for nickel-cadmium batteries made by the slurry technique can be controlled by adjusting the “slurry porosity”defined by the volume ratio of the liquid carrier to the slurry, besides sintering temperature and sintering time. The sintered porosity increased with an increase of slurry porosity, but only slight increment of the former was observed beyond a value of the latter (O.94).
The pore-size distribution of the plaque made by using methyl cellulose was scar e cely affected by the slurry porosity and showed almost uniform pore-size in the vicinity of 10 μm, while carboxymethylcellulose had a greater distribution of the pore-size ranging from 10 to 60 μm and the fraction of large pores increased as the slurry porosity increased. This beneficial effect of methylcellulose seems to arise from its surfactant activity, which probably yields more homogeneous dispersion of nickel powder.