PURPOSE: To realize the long life of a product by constituting a cathode electrode of a base electrode containing metal and an upper electrode comprising carbon powders dispersed in resin and formed in such a manner as covering the base electrode.
CONSTITUTION: A cathode electrode 2 is comprised of a base electrode 6 containing a metal(e.g.Ni) and an upper electrode 7 formed on the base electrode 6 and having carbon powders dispersed in resin serving as binders, thus preventing lead glass(conventional binder) from existing on the surface of the cathode electrode 2 and preventing electrode from being deteriorated when it becomes denser due to deposition of lead. Since the carbon powders are contained in the resin, a certain degree of conductivity is secured for preventing changes in a discharge characteristic of the electrode with time. Thus the long life of the product is ensured.
TERAO YOSHITAKA
KOBAYASHI HIROMI
SHIOZAWA NAOYUKI