Fabrication of solid-state battery cells and solid-state batteries

A method for fabricating a solid-state battery cell, the method comprising:

• forming a plurality of spaced electrically conductive structures on a substrate, wherein forming the plurality of spaced electrically conductive structures on the substrate comprises transforming at least part of a valve metal layer into a template comprising a plurality of spaced channels aligned longitudinally along a first direction, and wherein transforming at least part of the valve metal layer into the template comprises:
• a first anodization step, which anodizes at least part of the valve metal layer in a thickness direction to form a porous layer of valve metal oxide comprising a plurality of channels, wherein each channel comprises channel walls aligned longitudinally along the first direction and a channel bottom, wherein the channel bottom is coated with a first insulating metal oxide barrier layer as a result of the first anodization step;
• a protective treatment that induces hydrophobic surfaces to the channel walls and channel bottoms;
• a second anodization step after the protective treatment, which substantially removes the first insulating metal oxide barrier layer from the channel bottoms to induce anodization only at the bottoms of the plurality of channels and create a second insulating metal oxide barrier layer at the channel bottoms;
• and
• an etching step in an etching solution, wherein the etching step removes the second insulating metal oxide barrier layer from the channel bottoms, the method further comprising:
• depositing a solid functional material within the channels of the template to form the plurality of spaced structures inside the plurality of channels, wherein the plurality of spaced structures are aligned longitudinally along the first direction;
• forming a first layer of active electrode material on the plurality of spaced electrically conductive structures, wherein the first layer of active electrode material conformally coats surfaces of the plurality of spaced electrically conductive structures;
• depositing an electrolyte layer over the first layer of active electrode material;
• and
• forming a second layer of active electrode material over the electrolyte layer, wherein:
• the first layer of active electrode material forms a cathode layer of the solid-state battery cell and the second layer of active electrode material forms an anode layer of the solid-state battery cell;
• or
• the second layer of active electrode material forms the cathode layer of the solid-state battery cell and the first layer of active electrode material forms the anode layer of the solid-state battery cell.