The present invention generally relates to the use of a transition metal sulphide compound in a positive electrode for solid state batteries, to a transition metal sulphide compound, to a device or a material incorporating said compound, such as a composite material, an electrode, an electrochemical energy storage cell or a device such as an all-solid-state battery. It further relates to a method to manufacture and/or to use such a compound, material or device and to a process to manufacture said compound, material and/or device.