Abstract: Battery stacks are disclosed. In examples, the battery stack comprises a plurality of electrochemical cells. Each electrochemical cell of the plurality comprises a cathode layer, an electrolyte layer arranged on the cathode layer, and an anode layer arranged on the electrolyte layer. The battery stack comprises a cathode current collector comprising at least a first portion and a second portion, the first portion arranged on the cathode layer of a first electrochemical cell of the plurality of electrochemical cells, the second portion arranged on the cathode layer of a second electrochemical cell of the plurality of electrochemical cells. Between the first portion and second portion of the cathode current collector, the cathode current collector comprises an intermediate portion, at least one surface of which coated with an electrically-insulating coating.

Abstract: Solid-state electrochemical cells are disclosed. In examples, the cell comprises a cathode current collector, a sintered cathode layer arranged on the cathode current collector, a sintered electrolyte layer arranged on the sintered cathode layer, a sintered anode layer arranged on the sintered electrolyte layer, and an anode current collector arranged on the anode layer. Also described herein are methods of manufacturing said solid-state electrochemical cells, battery stacks comprising a plurality of said solid-state electrochemical cells, and electrically-powered devices comprising the solid-state electrochemical cell or battery stack.

Abstract: Methods of providing laminates are disclosed. In examples, the method involves providing an electrode containing electrode material; providing an electrolyte on a surface of the electrode, the electrolyte containing electrolyte material; and at least one of: reducing the roughness of the surface of the electrode before providing the electrolyte on the surface of the electrode; or heating the electrolyte material to a temperature of from 100°° C. to 300° C. Also described herein are methods of reducing mechanical stress in electrolytes, methods of reducing roughness of surfaces of electrodes, methods of providing electrochemical cells, electrochemical cells, and electrically-powered devices.

Abstract: Solid-state electrochemical cells are disclosed. In examples, the cell comprises a sintered cathode layer, an electrolyte layer, an anode layer arranged on at least part of the electrolyte layer, an anode current collector, and a cathode current collector. The sintered cathode layer comprises side surfaces having portions which extend in planes oblique to the plane in which the top and/or bottom surfaces of the sintered cathode layer extend. The electrolyte layer is arranged on at least one of these portions; the cathode current collector is arranged on at least another of these portions.

Abstract: A method of forming a layer of a cathode is provided. The method includes generating a plasma remote from one or more sputter targets, sputtering material from the target or targets using the plasma, and depositing the sputtered material on the substrate to which a bias voltage has been applied, thereby forming the layer of cathode.