# US 6,777,126 B1 · Fuel cell bipolar separator plate and current collector assembly and method of manufacture > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,777,126 B1 - Document ID: US6777126B1 - Status: Granted - Kind: B1 - Application number: 09/714,526 - Filed: 2000-11-16 - Granted: 2004-08-17 - Earliest claimed: 1999-11-16 - Assignees: GenCell Corporation - Inventors: Jeffrey P. Allen - Web page: https://patentgrep.com/patent/US6777126B1 ## CPC - H01M 8/026: characterised by grooves, e.g. their pitch or depth - B21D 13/02: by pressing - H01M 8/0202: Collectors; Separators, e.g. bipolar separators; Interconnectors - H01M 8/0206: Metals or alloys - H01M 8/0228: in the form of layered or coated products - H01M 8/0247: characterised by the form (characterised by a channel configuration H01M8/0258) - H01M 8/0254: corrugated or undulated - H01M 8/0265: the reactant or coolant channels having varying cross sections - H01M 8/0267: having heating or cooling means, e.g. heaters or coolant flow channels - H01M 8/0271: Sealing or supporting means around electrodes, matrices or membranes - H01M 8/0276: Sealing means characterised by their form (H01M8/0273 takes precedence) - H01M 8/2457: with both reactants being gaseous or vaporised - H01M 8/2483: characterised by internal manifolds - H01M 8/2484: characterised by external manifolds - H01M 8/04074: {Heat exchange unit structures specially adapted for fuel cell} - H01M 8/0625: {in a modular combined reactor/fuel cell structure} - Y02E 60/50: Fuel cells - Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product - Y10T 29/49108: Electric battery cell making - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - B21D: WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL (working or processing of wire B21F) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A fuel cell bipolar separator plate of variable length is formed from a sheet having a fixed width. The sheet is passed through a tool a predetermined distance and a pattern of ribs is formed on a central portion of the sheet with the tool to define a segment along the length of the sheet. The ribs define a fuel flow path on a first side of the sheet and an oxidant flow path on an opposed second side of the sheet. The sheet is passed through a tool a predetermined distance and the steps of forming the pattern on the sheet and passing the sheet through the tool are repeated until the sheet possesses a desired length, at which point the sheet is cut to a desired length. ## Claims ### Claim 1 A repeatable segment of a fuel cell bipolar separator plate comprising, in combination: a plate having a first surface and an opposing second surface; a plurality of ribs on the plate defining flow channels along the first surface and the second surface of the plate; a seal area extending along each of opposed side edges of the plate, the seal areas being formed by folding over edge portions of the plate onto one of the first surface and the second surface of the plate and including mating pairs of apertures configured to line up with one another when the edge portions are folded over, the seal areas and mating apertures forming internal inlet and outlet manifolds in fluid communication with the flow channels of one of the first surface and the second surface; and a seal member secured along each seal area on the other of the first surface and the second surface of the plate to define external inlet and outlet manifolds along side edges of the plate in fluid communication with the flow channels of the other of the first surface and the second surface. ### Claim 2 (depends on 1) The repeatable segment of claim 1, wherein the seal members include apertures configured to line up with corresponding apertures of the seal areas, the apertures of the seal members being eyeleted to the corresponding apertures of the seal areas. ### Claim 3 (depends on 2) The repeatable segment of claim 2, wherein the apertures of the seal members are double eyeleted to the corresponding apertures of the seal areas. ### Claim 4 (depends on 2) The repeatable segment of claim 2, wherein the eyeleted apertures further comprise a sealant. ### Claim 5 (depends on 1) The repeatable segment of claim 1, further comprising a pair of shims, each shim positioned between a seal member and the other of the first surface and the second surface of the plate. ### Claim 6 (depends on 1) The repeatable segment of claim 1, wherein at least some of the internal inlet and outlet manifolds comprise fuel inlet and fuel outlet manifolds. ### Claim 7 (depends on 1) The repeatable segment of claim 1, wherein at least some of the internal inlet and outlet manifolds comprise oxidant inlet and oxidant outlet manifolds. ### Claim 8 (depends on 1) The repeatable segment of claim 1, wherein at least some of the external inlet and outlet manifolds comprise fuel inlet and fuel outlet manifolds. ### Claim 9 (depends on 1) The repeatable segment of claim 1, wherein at least some of the external inlet and outlet manifolds comprise oxidant inlet and oxidant outlet manifolds. ### Claim 10 (depends on 1) The repeatable segment of claim 1, wherein cross-sectional areas of the flow channels on the first surface are one of larger than and smaller than cross-sectional areas of the flow channels on the second surface. ### Claim 11 (depends on 1) The repeatable segment of claim 1, wherein the seal areas include a plurality of dimples extending outwardly from the first surface of the plate and a plurality of dimples extending outwardly from the second surface of the plate. ### Claim 12 (depends on 1) The repeatable segment of claim 1, wherein the flow channels on the first and second surfaces extend substantially perpendicular to a direction of manufacture of the repeatable segment. ### Claim 13 (depends on 1) The repeatable segment of claim 1, wherein a portion of each end of the plate is folded over onto one of the first surface and the second surface of the plate to form first end seals. ### Claim 14 (depends on 13) The repeatable segment of claim 13, further comprising end seal members, the end seal members being secured to the other of the first surface and the second surface of the plate to form second end seals. ### Claim 15 (depends on 1) The repeatable segment of claim 1, further comprising an additional plate having a first surface and an opposing second surface, and a plurality of ribs defining flow channels along the second surface of the additional plate, the ribs of the plate having a height that is different than a height of the ribs of the additional plate, the first surface of the additional plate abutting the second surface of the plate such that the ribs of the additional plate are nested within the ribs of the plate to form center flow channels between the plate and the additional plate. ### Claim 16 (depends on 15) The repeatable segment of claim 15, wherein the center flow channels are coolant flow channels. ### Claim 17 (depends on 15) The repeatable segment of claim 15, wherein the center flow channels house a reformer. ### Claim 18 (depends on 15) The repeatable segment of claim 15, wherein a portion of each of the opposed ends of the plate are folded over onto the second surface of the additional plate to form opposed first end seals. ### Claim 19 (depends on 15) The repeatable segment of claim 15, further comprising a pair of end seal members, each end seal member being secured to the first surface of the plate at a respective end of the plate to form opposed second end seals. ### Claim 20 (depends on 19) The repeatable segment of claim 19, further comprising a pair of shims, each shim positioned between an end seal member and the first surface of the plate. ### Claim 21 (depends on 15) The repeatable segment of claim 15, wherein edge portions of the additional plate are folded over onto one of the second surface of the additional plate and the first surface of the plate. ### Claim 22 (depends on 15) The repeatable segment of claim 15, wherein edge portions of the plate and the additional plate are folded over onto the second surface of the additional plate. ### Claim 23 (depends on 15) The repeatable segment of claim 15, wherein edge portions of the additional plate are folded over onto the second surface of the additional plate and edge portions of the plate are folded over onto the first surface of the plate. ### Claim 24 (depends on 23) The repeatable segment of claim 23, wherein a sealant is applied to edge portions of the sheet between the plate and the additional plate. ### Claim 25 (depends on 1) The repeatable segment of claim 1, further comprising a pair of dividing sections, each dividing section being positioned between a corresponding seal area and the flow channels. ### Claim 26 (depends on 25) The repeatable segment of claim 25, wherein a plane of the dividing sections is closer to a plane of one of the first and second surfaces of the plate than it is to the plane of the other of the first and second surfaces of the plate. ### Claim 27 (depends on 1) The repeatable segment of claim 1, further comprising an additional plate having a first surface and an opposing second surface, and a plurality of ribs defining flow channels along the second surface of the additional plate, the first surface of the additional plate abutting the second surface of the plate such that the ribs of the additional plate are aligned with the ribs of the plate to form center flow channels between the plate and the additional plate. ### Claim 28 (depends on 1) The repeatable segment of claim 1, wherein comers of the plate are folded over and crimped to provide a seal. ### Claim 29 (depends on 1) The repeatable segment of claim 1, further comprising a plurality of flat wires spaced apart from one another and secured to one of the first surface and the second surface of the plate. ### Claim 30 A fuel cell bipolar separator plate comprising, in combination: a plate having a first surface and an opposing second surface; a plurality of ribs on the plate defining flow channels along the first surface and the second surface of the plate; a seal area extending along each of opposed side edges of the plate, the seal areas being formed by folding over edge portions of the plate onto one of the first surface and the second surface of the plate and including mating pairs of apertures configured to line up with one another when the edge portions are folded over, the seal areas and mating apertures forming internal inlet and outlet manifolds in fluid communication with the flow channels of one of the first surface and the second surface; and a seal member secured along each seal area on the other of the first surface and the second surface of the plate to define external inlet and outlet manifolds along side edges of the plate in fluid communication with the flow channels of the other of the first surface and the second surface. ### Claim 31 (depends on 30) The separator plate of claim 30, wherein the plate comprises at least one repeatable segment, each repeatable segment including an internal inlet manifold in one seal area and an internal outlet manifold in an opposing seal area. ### Claim 32 (depends on 31) The separator plate of claim 31, wherein each repeatable segment is separated from adjacent repeatable segments by dividing ribs. ### Claim 33 (depends on 32) The separator plate of claim 32, wherein the dividing ribs comprise fluid flow channels. ### Claim 34 (depends on 31) The separator plate of claim 31, wherein each repeatable segment includes an external inlet manifold in one seal area and an external outlet manifold in an opposing seal area. ### Claim 35 (depends on 34) The separator plate of claim 34, wherein each repeatable segment is separated from adjacent repeatable segments by dividing ribs that comprise fluid flow channels, the fluid flow channels extending beyond the flow channels on the first and second surfaces and into the opposing seal areas of the plate such that they are in fluid communication with the external manifolds. ### Claim 36 (depends on 30) The separator plate of claim 30, further comprising a pair of shims, each shim positioned between a seal member and the other of the first surface and the second surface of the plate. ### Claim 37 (depends on 30) The separator plate of claim 30, wherein the seal members include apertures configured to line up with corresponding apertures of the seal areas, the apertures of the seal members being eyeleted to the corresponding apertures of the seal areas. ### Claim 38 (depends on 30) The separator plate of claim 30, wherein the plate comprises a plurality of segments positioned between first and second end segments. ### Claim 39 (depends on 30) The separator plate of claim 30, wherein a portion of each end of the plate is folded over onto one of the first and second surfaces of the plate to form opposed first end seals. ### Claim 40 (depends on 39) The separator plate of claim 39, further comprising a pair of end seal members, each end seal member being secured to the other of the first and second surfaces of the plate at a respective end of the plate to form opposed second end seals. ### Claim 41 (depends on 40) The separator plate of claim 40, further comprising a pair of shims, each shim positioned between an end seal member and the other of the first and second surfaces of the plate. ### Claim 42 (depends on 30) The separator plate of claim 30, wherein comers of the plate are folded over and crimped to provide a seal. ### Claim 43 (depends on 30) The separator plate of claim 30, further comprising a plurality of flat wires spaced apart from one another and secured to one of the first surface and the second surface of the plate. ### Claim 44 A bipolar separator plate comprising, in combination: a first sheet of metal having a plurality of ribs in a central area thereof, the ribs forming flow channels on a first surface of the first sheet; a second sheet of metal having a plurality of ribs in a central area thereof, the ribs of the second sheet having a depth shallower than a depth of the ribs of the first sheet and forming flow channels on a second surface of the first sheet, a first surface of the second sheet abutting a second surface of the first sheet such that the ribs of the second sheet are nested within the ribs of the first sheet to form center flow channels between the first and second sheets; opposing edge seal areas of the first and second sheets having mating pairs of apertures and being folded over themselves onto one of the first surface of the first sheet and the second surface of the second sheet, such that the apertures of each pair of apertures are aligned with one another and the folded over seal areas form opposing internal inlet and outlet manifolds; and a pair of strips of sheet metal, each strip being attached to the first sheet at an intersection of a seal area and the flow channels on the first surface of the first sheet and having a plurality of apertures that align with corresponding apertures of the first and second sheets, the strips forming external inlet and outlet manifolds at open edges of the bipolar plate. ### Claim 45 (depends on 44) The separator plate of claim 44, wherein the plate is composed of repeated segments. ### Claim 46 (depends on 44) The separator plate of claim 44, wherein at least some apertures of the first and second sheets and the strips of metal are eyeleted together such that an internal inlet manifold and an internal outlet manifold in opposing seal areas are in fluid communication with flow channels on the first surface of the first sheet. ### Claim 47 (depends on 44) The separator plate of claim 44, wherein at least some apertures of the first and second sheets and the strips of metal are eyeleted together such that an internal inlet manifold and an internal outlet manifold in opposing seal areas are in fluid communication with flow channels on the second surface of the second sheet. ### Claim 48 (depends on 44) The separator plate of claim 44, wherein at least some apertures of the first and second sheets and the strips of metal are eyeleted together such that an internal inlet manifold and an internal outlet manifold in opposing seal areas are in fluid communication with the center flow channels. ### Claim 49 (depends on 44) The separator plate of claim 44, wherein the external inlet and outlet manifolds are in fluid communication with the center flow channels. ### Claim 50 (depends on 44) The separator plate of claim 44, wherein at least some of the internal inlet and outlet manifolds comprise fuel inlet and fuel outlet manifolds. ### Claim 51 (depends on 44) The separator plate of claim 44, wherein at least some of the internal inlet and outlet manifolds comprise oxidant inlet and oxidant outlet manifolds. ### Claim 52 (depends on 44) The separator plate of claim 44, wherein at least some of the external inlet and outlet manifolds comprise fuel inlet and fuel outlet manifolds. ### Claim 53 (depends on 44) The separator plate of claim 44, wherein at least some of the external inlet and outlet manifolds comprise oxidant inlet and oxidant outlet manifolds. ### Claim 54 The separator plate of claim wherein edge portions of the first sheet and the second sheet are folded over onto the second surface of the second sheet. ### Claim 55 (depends on 44) The separator plate of claim 44, wherein edge portions of the second sheet are folded over onto the second surface of the second sheet and edge portions of the first sheet are folded over onto the first surface of the first sheet. ### Claim 56 (depends on 44) The separator plate of claim 44, wherein a sealant is applied between the first sheet and the second sheet along edges thereof. ### Claim 57 (depends on 44) The separator plate of claim 44, wherein cross-sectional areas of the flow channels on the first surface of the first sheet are one of larger than and smaller than cross-sectional areas of the flow channels on the second surface of the second sheet. ### Claim 58 (depends on 44) The separator plate of claim 44, wherein the seal areas include a plurality of dimples extending outwardly from the surfaces of the first and second sheet. ### Claim 59 (depends on 44) The separator plate of claim 44, wherein the separator plate is divided into segments, each segment including at least one internal inlet manifold in one seal area and at least one internal outlet manifold in the opposing seal area. ### Claim 60 (depends on 59) The separator plate of claim 59, wherein each segment is separated from adjacent segments by dividing ribs. ### Claim 61 (depends on 60) The separator plate of claim 60, wherein the dividing ribs comprise fluid flow channels. ### Claim 62 (depends on 59) The separator plate of claim 59, wherein each segment includes an external inlet manifold in one seal area and an external outlet manifold in the opposing seal area. ### Claim 63 (depends on 59) The separator plate of claim 59, wherein each segment is separated from adjacent segments by dividing ribs that comprise fluid flow channels, the fluid flow channels extending beyond the flow channels on the first and second surfaces and into the opposing seal areas of the plate such that they are in fluid communication with the external manifolds. ### Claim 64 (depends on 44) The separator plate of claim 44, wherein the flow channels on the first surface of the first sheet and the second surface of the second sheet extend substantially perpendicular to a direction of manufacture of the separator plate. ### Claim 65 (depends on 44) The separator plate of claim 44, wherein the first plate has a thickness sufficient to withstand a compressive force applied to a fuel cell stack comprising a plurality of nested first and second sheets. ### Claim 66 (depends on 44) The separator plate of claim 44, wherein the second sheet has a thickness sufficient to withstand a differential gas pressure between the flow channels on the second surface of the second sheet and the center flow channels, and insufficient to withstand a compressive force applied to a fuel cell stack comprising a plurality of nested first and second sheets. ### Claim 67 (depends on 44) The separator plate of claim 44, wherein the center flow channels are coolant flow channels. ### Claim 68 (depends on 44) The separator plate of claim 44, wherein the center flow channels house a reformer. ### Claim 69 (depends on 44) The separator plate of claim 44, wherein a portion of each of the opposed ends of the first and second sheets are folded over onto the second surface of the second sheet to form opposed first end seals. ### Claim 70 (depends on 44) The separator plate of claim 44, further comprising a pair of end seal members, each end seal member being secured to the first surface of the first sheet at a respective end of the first sheet to form opposed second end seals. ### Claim 71 (depends on 44) The separator plate of claim 44, wherein the first and second sheets each further comprise a pair of dividing sections, each dividing section being positioned between a corresponding seal area and the flow channels. ### Claim 72 (depends on 44) The separator plate of claim 44, wherein a plane of each dividing section is closer to a plane of one of the first and second sheets than it is to the plane of the other of the first and second sheets. ### Claim 73 (depends on 44) The separator plate of claim 44, wherein corners of the first and second sheets of metal are folded over and crimped to provide a seal. ### Claim 74 (depends on 44) The separator plate of claim 44, further comprising a plurality of flat wires spaced apart from one another and secured to one of the first surface of the first sheet of metal and the second surface of the second sheet of metal. ### Claim 75 A fuel cell assembly comprising, in combination: a housing; a fuel cell stack disposed in the housing, the fuel cell stack comprising a first sheet of metal having a plurality of ribs in a central area thereof, the ribs having a first depth and forming flow channels on a first surface of the first sheet; a second sheet of metal having a plurality of ribs in a central area thereof, the ribs of the second sheet having a second depth shallower than the first depth and forming flow channels on a second surface of the first sheet, a first surface of the second sheet abutting a second surface of the first sheet such that the ribs of the first and second sheets are nested with one another to form center flow channels between the first and second sheets; opposing edge seal areas of the first and second sheets having mating pairs of apertures and being folded over themselves onto one of the first surface of the first sheet and the second surface of the second sheet, such that the apertures of each pair of apertures are aligned with one another and the folded over seal areas form opposing internal inlet and outlet manifolds; and a pair of strips of sheet metal, each strip being attached to the first sheet at an intersection of a seal area and the flow channels on the first surface of the first sheet and having a plurality of apertures that align with corresponding apertures of the first and second sheets, the strips forming external inlet and outlet manifolds at open edges of the bipolar plate; and a pair of seals, each seal positioned between the fuel cell stack and the housing. ### Claim 76 A fuel cell bipolar separator plate comprising, in combination: a first plate having a first surface and an opposing second surface; a plurality of ribs on the first plate defining a fuel flow path along the first surface of the first plate; a second plate having a first surface and an opposing second surface; a plurality of ribs on the second plate defining an oxidant flow path along the second surface of the second plate; wherein the ribs on one of the first and second plates have a height different than the ribs on the other plate, and peaks of the ribs on one side of one of the first and second plates are in abutting relationship with corresponding peaks of the ribs on one side of the other of the first and second plates to define a coolant flow path between the first and second plates. ### Claim 77 (depends on 76) The separator plate of claim 76, wherein the fuel flow path, oxidant flow path, and coolant flow path are substantially parallel to one another. ### Claim 78 (depends on 76) The separator plate of claim 76, wherein the fuel flow path, oxidant flow path, and coolant flow path are substantially perpendicular to a direction of manufacture of the first and second plate. ### Claim 79 (depends on 76) The separator plate of claim 76, further comprising seal areas along each side edges of the first plate. ### Claim 80 (depends on 79) The separator plate of claim 79, wherein the seal areas are formed by folding over a portion of the first plate onto itself. ### Claim 81 (depends on 80) The separator plate of claim 80, wherein the seal areas include a plurality of dimples defining a fluid flow path within the folded over portions of the plate. ### Claim 82 (depends on 80) The separator plate of claim 80, wherein the first and second plates include a plurality of segments, each segment including at least one fuel inlet in one seal area and at least one corresponding fuel outlet in the opposing seal area of that segment, the inlet and outlet communicating with one another through the fuel flow path of that segment. ### Claim 83 (depends on 82) The separator plate of claim 82, wherein each fuel inlet and fuel outlet comprises a mating pair of apertures formed in the seal areas such that the mating pair of apertures line up with one another when the first plate is folded over onto itself. ### Claim 84 (depends on 80) The separator plate of claim 80, wherein the first and second plates include a plurality of segments, each segment including an oxidant inlet in one seal area and a corresponding oxidant outlet in the opposing seal area of that segment, the oxidant inlet and outlet communicating with one another through the oxidant flow path of that segment. ### Claim 85 (depends on 84) The separator plate of claim 84, further comprising an oxidant seal member secured along each edge of the plate to define the oxidant inlet and oxidant outlet ### Claim 86 (depends on 85) The separator plate of claim 85, wherein the seal areas include a plurality of dimples defining a fluid flow path between the seal members and the plate. ### Claim 87 (depends on 76) The separator plate of claim 76, wherein a central portion of each end of each plate is folded over onto itself to form a seal along the respective end of each plate. ### Claim 88 (depends on 87) The separator plate of claim 87, further comprising recesses formed along sides of each end of each plate outward of the central portions and shaped to receive the central portions when the central portions are folded over. ### Claim 89 (depends on 80) The separator plate of claim 80, wherein each segment further includes at least one coolant inlet in one seal area and at least one corresponding coolant outlet in the opposing seal area of that segment, the coolant inlet and coolant outlet communicating with one another through the coolant flow path of that segment. ### Claim 90 (depends on 89) The separator plate of claim 89, wherein each coolant inlet and coolant outlet comprises a mating pair of apertures formed in the seal areas such that the mating pair of apertures line up with one another when the first plate is folded over onto itself. ### Claim 91 (depends on 76) The separator plate of claim 76, wherein the ribs of the first and second plate are of a height sufficient to withstand a compressive force applied to a fuel cell stack comprising a plurality of first and second plates.