Conductive coating for positive earth in electrochemical cell - comprising e.g. soln. of PVC in tetra:hydro:furan contg. graphite particles

摘要

Good electrical contact between a positive earth formed according to Parent patent and the positive current collector of an electrical generator using Zn-MnO2 and Mg-MnO2 couples, is ensured by coating the felt or gauze of carbon or graphite, prior to its impregnation with MnO2, on the surface which will be in contact with the positive collector, with a thin layer of conducting material. This avoids adverse effect on the electrical contact due to the presence of MnO2 on this surface. Partic, the coating material is a resin consisting of PVC dissolved in THF (12.5 wt.% PVC/87.5 wt.% THF), contg. a mixt. of lamellar graphite (size 0.1-0.4 mm) and spheroidal graphite (size =0.6 mu).