# US 2014/0190545 A1 · Integrated back-sheet assembly for photovoltaic module > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0190545 A1 - Document ID: US20140190545A1 - Status: Published application - Kind: A1 - Application number: 14/151,120 - Filed: 2014-01-09 - Published: 2014-07-10 - Earliest claimed: 2013-01-10 - Assignees: E. I. Du Pont de Nemours and Company - Applicants: E I Du Pont De Nemours and Company - Inventors: CHANGMING LEI; ZELIN LIU; MINFANG MU - Web page: https://patentgrep.com/patent/US20140190545A1 ## CPC - H10F 19/908: {for back-contact photovoltaic cells} - H10F 19/85: Protective back sheets - Y02E 10/50: Photovoltaic [PV] energy - Y10T 156/1057: Subsequent to assembly of laminae - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A process for forming a back-sheet assembly for a photovoltaic module having multiple solar cells with back-side electrical contacts includes providing a substrate, adhering an electrically conductive metal circuit to the substrate, adhering release pads to the metal circuit in a pattern, adhering an insulating layer to the metal circuit, forming openings in said insulating layer in a pattern over the release pads, and filling the openings with electrically conductive material that is in electrical contact with the electrically conductive metal circuit. A process for forming a photovoltaic module with this back-sheet assembly is also provided. The back-sheet assembly and photovoltaic module made with the back-sheet assembly are also provided. ## Claims ### Claim 1 A process for forming a back-sheet assembly for a photovoltaic module having multiple solar cells with back-side electrical contacts, comprising: providing a substrate having a back surface and a front surface; adhering an electrically conductive metal circuit to the front surface of said substrate; adhering a plurality of release pads to the electrically conductive metal circuit in a pattern; adhering an insulating layer to said electrically conductive metal circuit over said electrically conductive metal circuit and said release pads; forming a plurality of openings in said insulating layer in a pattern corresponding to the pattern in which the release pads are adhered to the electrically conductive metal circuit; and filling said plurality of openings in said insulating layer with an electrically conductive material such that the electrically conductive material is in electrical contact with said electrically conductive metal circuit. ### Claim 2 (depends on 1) The process of claim 1 wherein the forming of a plurality of openings in said insulating layer comprises drilling the insulating layer to form a plurality openings in said insulating layer, said openings being disposed over the corresponding release pads. ### Claim 3 (depends on 1) The process of claim 1 wherein the forming of a plurality of openings in said insulating layer comprises the steps of: cutting said insulating layer to form a plurality of cut sections in said insulating layer, said cut sections being disposed over corresponding release pads and being defined by a cut in the insulating layer; removing said cut sections in said insulating layer from said insulating layer to provide the plurality of openings in said insulating layer in a pattern corresponding to the pattern in which the release pads were adhered to the electrically conductive metal circuit. ### Claim 4 (depends on 3) The process of claim 3 wherein said release pads are comprised of polymer. ### Claim 5 (depends on 4) The process of claim 4 wherein said release pads are screen printed on said electrically conductive metal circuit. ### Claim 6 (depends on 4) The process of claim 4 wherein said release pads are formed by casting, extruding or laminating a polymer layer on said electrically conductive metal circuit, cutting the polymer layer to form said release pads in said polymer layer and polymer layer portions between and around said release pads, and removing said polymer layer portions between and around said release pads. ### Claim 7 (depends on 1) The process of claim 1 wherein said insulating layer comprises a polymer insulating layer. ### Claim 8 (depends on 7) The process of claim 7 wherein said polymer insulating layer is extruded, laminated or cast on said electrically conductive metal circuit. ### Claim 9 (depends on 7) The process of claim 7 wherein said insulating layer comprises at least two layers. ### Claim 10 (depends on 9) The process of claim 9 wherein said at least two layers comprise an ILD adhered to said electrically conductive metal circuit and an encapsulant layer adhered to said ILD. ### Claim 11 (depends on 3) The process of claim 3 wherein the cutting of said insulating layer to form a plurality of cut sections is done by die cutting, laser cutting, or calendering. ### Claim 12 (depends on 1) The process of claim 1 wherein said release pads are comprised of an electrically conductive material, and wherein the peel strength between said release pads and said electrically conductive metal circuit is greater than the peel strength between said release pads and the insulating layer, such that the removing of the cut sections of the insulating layer over said release pads leaves the release pads adhered to the electrically conductive metal circuit. ### Claim 13 (depends on 1) The process of claim 1 wherein said release pads are comprised of a polymeric release film, and wherein the peel strength between said release pads and said electrically conductive metal circuit is less than the peel strength between said release pads and the insulating layer, such that the removing the cut sections of the insulating layer over said release pads also removes the release pads from the electrically conductive metal circuit. ### Claim 14 (depends on 1) The process of claim 1 wherein in the step of filling said plurality of openings in insulating layer with electrically conductive material, the electrically conductive material comprises a plurality of electrically conductive solid objects that are inserted into corresponding openings in said insulating layer. ### Claim 15 (depends on 1) The process of claim 1 wherein in the step of filling said plurality of openings in insulating layer with electrically conductive material, the electrically conductive material is an electrically conductive adhesive in the form of a liquid, a melt or a powder. ### Claim 16 (depends on 15) The process of claim 15 wherein said electrically conductive adhesive is a polymer filled with conductive metal particles. ### Claim 17 (depends on 1) The process of claim 1 wherein said electrically conductive metal circuit comprises a plurality of electrically conductive circuits formed from an electrically conductive metal foil. ### Claim 18 (depends on 1) A process for forming a back-contact photovoltaic module, comprising: providing a back-sheet assembly for a photovoltaic module of claim 1; providing a plurality of back-contact solar cells having a light receiving side and an opposite back side, said back-contact solar cells each having a plurality of electrical contacts on their back side in a pattern corresponding to the pattern of openings in the insulating layer that are filled with electrically conductive material; and adhering the back side of the plurality of back-contact solar cells to the insulating layer such that the electrical contacts on the back side of the solar cells are in electrical contact with the electrically conductive metal circuit through the electrically conductive material in the openings in said insulating layer. ### Claim 19 A back-sheet assembly for photovoltaic module having multiple solar cells each having back-side electrical contacts, comprising: a substrate having a back surface and a front surface; an electrically conductive metal circuit adhered to the front surface of said substrate; a plurality of electrically conductive release pads adhered to said electrically conductive metal circuit in a pattern; an insulating layer adhered to said electrically conductive metal circuit; a plurality of openings in said insulating layer over said release pads, said openings being filled with an electrically conductive material and being in a pattern corresponding to the pattern of the release pads adhered to said conductive circuit. ### Claim 20 (depends on 19) The back-sheet assembly of claim 19 wherein the insulating layer comprises an ILD adhered to said electrically conductive metal circuit and an encapsulant layer adhered to said ILD. ### Claim 21 (depends on 19) A back-contact photovoltaic module comprising: the back-sheet assembly for a photovoltaic module of claim 19; a plurality of back-contact solar cells having a light receiving side and an opposite back side, said back contact solar cells each having a plurality of electrical contacts on their back side in a pattern corresponding to the pattern of openings in the insulating layer that are filled with electrically conductive material; and wherein the back side of the plurality of back-contact solar cells are adhered to the insulating layer such that the electrical contacts on the back side of the solar cells are in electrical contact with the electrically conductive metal circuit through the electrically conductive material in the openings in said insulating layer.