GB187584A - Improvements in or relating to negative electrodes for electric accumulators - Google Patents

Abstract

187,584. Gross, C. Oct. 17, 1921, [Convention date]. No Patent granted (Sealing fee not paid). Electrodes.- A negative electrode for an accumulator consists of an oxide of manganese together with a hydrogen-transmitting substance such as palladium or a metal of the platinum group. The mixture may be pressed into the form of a plate or it may be attached to a grid. The mass may be rendered porous by adding a chlorine or bromine compound of manganese or other metal in the same group, the halogen being subsequently removed by chemical or electrolytic means. In an example manganic oxide is added tn a saturated solution of manganese chloride containing 1 per cent of palladium chloride to form a dough which is pressed into the form of a plate or introduced into a metal grid. The plate is then dried and placed in sulphuric acid whereby a part of the halogen is liberated, the plate being then ready for use as an accumulator electrode. During the first charge the manganic oxide is reduced to manganous oxide, and during the subsequent discharge the remaining halogen is liberated. The Specification as open to inspection under Sect. 91 (3) (a) states that the active material may consist of an oxide of a metal capable of forming several oxygen compounds, porosity being obtained bv the addition of a chlorine or bromine compound of the same metal or a metal in the same group. This subject-matter does not appear in the Specification as accepted.