A process for producing an all-solid thin-layer battery including the following series of steps: a) a layer including at least one anode material (referred to here as "anode material layer") is deposited on its conductive substrate, preferably selected from the group formed by a metal sheet, a metal strip, a metallised insulating sheet, a metallised insulating strip, a metallised insulating film, said conductive substrates, or conductive elements thereof, capable of serving as an anode current collector; b) a layer including at least one cathode material (referred to here as "cathode material layer") is deposited on its conductive substrate, preferably selected from the group formed by a metal sheet, a metal strip, a metallised insulating sheet, a metallised insulating strip, a metallised insulating film, said conductive substrates, or conductive elements thereof, capable of serving as a cathode current collector, with the understanding that steps a) and b) can be reversed; c) on at least one layer obtained in step a) and/or b), a layer including at least one solid electrolyte material (referred to here as "electrolyte material layer") is deposited; d) a layer of a cross-linked polymer material, preferably chosen from polymethyl methacrylates, polyamines, polyimides or polysiloxanes, comprising ionic groups having a thickness of less than 10 μm, preferably less than 5 μm, and even more preferably less than 2 μm, is deposited: - on the anode material layer coated with a solid electrolyte material layer and/or on the cathode material layer coated or not with a solid electrolyte material layer; - or on the cathode material layer coated with a solid electrolyte material layer and/or on the anode material layer coated or not with a solid electrolyte material layer; e) an anode material layer obtained in step a), c) or d) is stacked face to face in series with a cathode material layer obtained in step b), c) or d) with the understanding that the stack includes at least one solid electrolyte material layer obtained in step c) and at least one cross-linked polymer material layer obtained in step d); f) a heat treatment and/or a mechanical compression of the stack obtained in step e) is carried out in order to obtain an all-solid thin-layer battery. a) a layer including at least one anode material (referred to here as "anode material layer") is deposited on its conductive substrate, preferably selected from the group formed by a metal sheet, a metal strip, a metallised insulating sheet, a metallised insulating strip, a metallised insulating film, said conductive substrates, or conductive elements thereof, capable of serving as an anode current collector; b) a layer including at least one cathode material (referred to here as "cathode material layer") is deposited on its conductive substrate, preferably selected from the group formed by a metal sheet, a metal strip, a metallised insulating sheet, a metallised insulating strip, a metallised insulating film, said conductive substrates, or conductive elements thereof, capable of serving as a cathode current collector, with the understanding that steps a) and b) can be reversed; c) on at least one layer obtained in step a) and/or b), a layer including at least one solid electrolyte material (referred to here as "electrolyte material layer") is deposited; d) a layer of a cross-linked polymer material, preferably chosen from polymethyl methacrylates, polyamines, polyimides or polysiloxanes, comprising ionic groups having a thickness of less than 10 μm, preferably less than 5 μm, and even more preferably less than 2 μm, is deposited: - on the anode material layer coated with a solid electrolyte material layer and/or on the cathode material layer coated or not with a solid electrolyte material layer; - or on the cathode material layer coated with a solid electrolyte material layer and/or on the anode material layer coated or not with a solid electrolyte material layer; - on the anode material layer coated with a solid electrolyte material layer and/or on the cathode material layer coated or not with a solid electrolyte material layer; - or on the cathode material layer coated with a solid electrolyte material layer and/or on the anode material layer coated or not with a solid electrolyte material layer; e) an anode material layer obtained in step a), c) or d) is stacked face to face in series with a cathode material layer obtained in step b), c) or d) with the understanding that the stack includes at least one solid electrolyte material layer obtained in step c) and at least one cross-linked polymer material layer obtained in step d); f) a heat treatment and/or a mechanical compression of the stack obtained in step e) is carried out in order to obtain an all-solid thin-layer battery.