Abstract: There are provided primary cells comprising a negative lithium electrode and a positive CrO.sub.x cathode wherein 2.ltoreq..times..ltoreq.2.9. These cells are devoid of the conventional separator between the electrodes. Instead, there is provided at the outer face of the chromium oxide electrode, a barrier layer formed by the reaction of lithium and chromium oxide. The exact constitution of this barrier layer is not known. The barrier layer is ion conductive but not electro-conductive and has a substantially lower ohmic resistance than the conventional polypropylene or paper separators. There is thus provided a cell of high current capacity. Such cells can also be constructed utilizing magnesium dioxide, silver monoxide and disilver oxide or nickel hydroxide provided that said metal oxie cathodes are coated with a covering of chromium oxide.