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WO2010065022A1 - Connecteurs électriques à base de nanotubes de carbone - Google Patents

Connecteurs électriques à base de nanotubes de carbone Download PDF

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Publication number
WO2010065022A1
WO2010065022A1 PCT/US2008/013428 US2008013428W WO2010065022A1 WO 2010065022 A1 WO2010065022 A1 WO 2010065022A1 US 2008013428 W US2008013428 W US 2008013428W WO 2010065022 A1 WO2010065022 A1 WO 2010065022A1
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WIPO (PCT)
Prior art keywords
electrical
carbon nanotubes
polymer
electrical connector
electrically
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PCT/US2008/013428
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English (en)
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Michael T. Searfass
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Priority to PCT/US2008/013428 priority Critical patent/WO2010065022A1/fr
Publication of WO2010065022A1 publication Critical patent/WO2010065022A1/fr
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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R4/00—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation
    • H01R4/28—Clamped connections, spring connections
    • H01R4/50—Clamped connections, spring connections utilising a cam, wedge, cone or ball also combined with a screw
    • H01R4/5033—Clamped connections, spring connections utilising a cam, wedge, cone or ball also combined with a screw using wedge or pin penetrating into the end of a wire in axial direction of the wire
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
    • C08J5/005—Reinforced macromolecular compounds with nanosized materials, e.g. nanoparticles, nanofibres, nanotubes, nanowires, nanorods or nanolayered materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/20—Conductive material dispersed in non-conductive organic material
    • H01B1/24—Conductive material dispersed in non-conductive organic material the conductive material comprising carbon-silicon compounds, carbon or silicon
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R4/00—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation
    • H01R4/10—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation effected solely by twisting, wrapping, bending, crimping, or other permanent deformation
    • H01R4/18—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation effected solely by twisting, wrapping, bending, crimping, or other permanent deformation by crimping
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R13/00—Details of coupling devices of the kinds covered by groups H01R12/70 or H01R24/00 - H01R33/00
    • H01R13/02—Contact members
    • H01R13/03—Contact members characterised by the material, e.g. plating, or coating materials

Definitions

  • Modern power cables come in a variety of sizes, materials, and types, each cable being particularly adapted to its end use. Cables are constructed from three major design components: conductors, insulations, and protective layers. The construction details of individual cables vary according to their intended application. A variety of connections are available for power cables, such as male connections (plugs), female connections (sockets), twist-on connections, and alligator clips.
  • Carbon nanotubes have been proposed to replace metal-based conductors in certain applications due to their high conductivity, strength, and light weight. Carbon nanotubes are known to display a range of electric properties. For example, single- wall carbon nanotubes (SWNTs) can be metallic conductors, semi-metallic conductors, semiconductors, or insulators depending on their chirality. Carbon nanotube/polymer composites offer significant mechanical strength, as well as electrical conductvity when conducting carbon nanotubes are blended in the polymer. Orientation of the carbon nanotubes in the polymer composite can influence both the mechanical and electrical properties of the composite material. Despite the potential benefits offered by carbon nanotubes, commercial success in electrical and mechanical applications utilizing these species has not yet been realized.
  • SWNTs single- wall carbon nanotubes
  • Carbon nanotube/polymer composites offer significant mechanical strength, as well as electrical conductvity when conducting carbon nanotubes are blended in the polymer. Orientation of the carbon nanotubes in the polymer composite can influence both the mechanical and electrical properties of the composite material
  • electrical connectors and devices based on carbon nanotubes represent a significant unmet commercial need. Further, the electrical connectors and devices should be easily constructed and be simply integrated into existing electrical applications. For example, lightweight, highly-conducting electrical cables based on carbon nanotubes dispersed in a polymer and formed into a cable having conventional cable connections would be of particular commerical interest.
  • electrical connectors comprise at least one polymer, carbon nanotubes, and an electrical conductor.
  • the carbon nanotubes are dispersed in the at least one polymer to form an electrically- conducting carbon nanotube/polymer dispersion.
  • the electrical conductor comprises two electrical connection points.
  • the electrical conductor comprises at least one metal. A first of the two electrical connection points contacts the carbon nanotube/polymer dispersion. A second of the two electrical connection points comprises a standard electrical connection.
  • methods for constructing electrical connectors include preparing a dispersion of carbon nanotubes in a polymer, preparing an electrical conductor comprising at least one metal, and connecting the electrical conductor and the dispersion.
  • the carbon nanotubes in the dispersion are at least partially aligned.
  • the electrical conductor includes a first electrical connection point and a second electrical connection point.
  • the first electrical connection point comprises a plurality of electrically-conducting pins.
  • methods for transmitting electric current comprise providing an electrical connector as described herein and connecting the electrical connector to a power source.
  • FIGURE 1 illustrates an embodiment of an electrical connector comprising carbon nanotubes dispersed in a polymer and having standard electrical connections;
  • FIGURE 2 illustrates a plot of volume conductivity versus SWNT concentration in a urethane-methacrylate polymer, as measured both in the presence and absence of an applied voltage
  • FIGURE 3 illustrates a first derivative plot of volume conductivity versus SWNT concentration in a urethane-methacrylate polymer for measurements made in the presence of an applied voltage
  • FIGURE 4 illustrates a first derivative plot of volume conductivity versus SWNT concentration in a urethane-methacrylate polymer for measurements made in the absence of an applied voltage
  • FIGURE 5 illustrates a plot of volume conductivity versus the logarithm of (SWNT wt. % - percolation threshold wt. %) in the presence and absence of an applied voltage;
  • FIGURE 6 illustrates an exemplary spreadsheet used for inputing and calculating various electrical connector construction parameters.
  • the calculated carbon nanotube percentage does not represent physical reality as calculated based on the input parameters;
  • FIGURE 7 illustrates an exemplary spreadsheet used for inputing and calculating various electrical connector construction parameters.
  • the calculated carbon nanotube percentage represents a physically realistic carbon nanotube percentage as determined based on the input parameters;
  • FIGURE 8 illustrates various electrical connector construction parameters for some common voltages and currents applicable to AC and DC power.
  • FIGURE 9 illustrates a plot of carbon nanotube/polymer dispersion diameter and pin sizing versus power requirements of various electrical connectors.
  • Contact refers to, for example, a condition where two or more bodies touch one another. In some embodiments, contact may comprise surface contact between the two or more bodies. In some embodiments, contact may comprise touching of one or more of the bodies to the interior of an adjacent body. Contact may occur at a single point or at a plurality of points.
  • Corrosion-resistant metal refers to, for example, an electroplated metal which is less galvanically noble than a metal on to which the corrosion-resistant metal is electroplated.
  • corrosion-resistant metal refers to, for example, any sacrificial or protective metal applied to prevent corrosion in a specific chemical environment. In various embodiments presented hereinbelow, corrosion- resistant metals protect and maintain functionality of electrical connectors.
  • carbon nanotubes are referenced.
  • carbon nanotubes may be formed by any known technique in any length, diameter and chirality.
  • carbon nanotubes may exist in bundles of aggregated nanotubes or as debundled individual nanotubes.
  • carbon nanotubes may be purified or unpurified.
  • carbon nanotubes may be functionalized or unfunctionalized.
  • the carbon nanotubes may have any number of concentric walls, including but not limited to, single- wall carbon nanotubes (SWNTs), double-wall carbon nanotubes (DWNTs), and multi- wall carbon nanotubes (MWNTs).
  • SWNTs single- wall carbon nanotubes
  • DWNTs double-wall carbon nanotubes
  • MWNTs multi- wall carbon nanotubes
  • SWNTs may have (n-m) chirality indices that provide metallic, semi-metallic or semiconducting forms.
  • SWNTs may be physically or chemically separated to provide SWNTs in pure or highly- enriched metallic, semi-metallic or semi-conducting forms.
  • carbon nanotubes may also be shortened, such as those obtained, for example, through oxidative reaction of carbon nanotubes in a mixture of nitric acid and fuming sulfuric acid (oleum).
  • the carbon nanotubes may be functionalized with organic groups. A number of methods for functionalizing carbon nanotubes with a wide range of organic groups are well known to those of skill in the relative art. Functionalization of carbon nanotubes may occur on the ends of the carbon nanotubes, on the sidewalls of the carbon nanotubes, or a combination thereof.
  • carbon nanotubes are dispersed in a polymer.
  • the carbon nanotubes may be unbound to the polymer or covalently-bound to the polymer.
  • the carbon nanotubes become an integral part of the polymer structure.
  • the present disclosure describes electrical connectors having standard electrical connections. Electrical conduction in the electrical connectors is provided by a polymer composite having carbon nanotubes dispersed in the polymer matrix. Various embodiments of the physical forms of the electrical connectors, fabrication methods, and design algorithms have been established and are presented hereinbelow.
  • electrical connectors are disclosed herein.
  • the electrical connectors comprise at least one polymer, carbon nanotubes, and an electrical conductor comprising two electrical connection points.
  • the carbon nanotubes are dispersed in the at least one polymer to form an electrically-conducting carbon nanotube/polymer dispersion.
  • the electrical conductor comprises at least one metal.
  • a first of the two electrical connection points contacts the carbon nanotube/polymer dispersion.
  • a second of the two electrical connection points comprises a standard electrical connection.
  • FIGURE 1 presents an illustrative embodiment of such an electrical connector 100.
  • the electrical connector has standard electrical connections 111. In FIGURE 1, the standard electrical connection 111 is a plug.
  • the electrical connector 100 includes an electrically- conducting carbon nanotube/polymer dispersion 101 and metallic electrical conductor 102.
  • the electrically-conducting carbon nanotube/polymer dispersion 101 may be lined with shielding foil 104, insulation 105 or a combination thereof to confine, isolate and protect the electrically-conducting carbon nanotube/polymer dispersion 101.
  • the metallic electrical conductor 102 further comprises a first electrical connection point 1021 and a second electrical connection point 1022.
  • the first electrical connection point 1021 contacts the electrically-conducting carbon nanotube/polymer dispersion 101.
  • the second electrical contact point 1022 comprises standard electrical connection 111.
  • Illustrative standard electrical connections 111 include, for example, wires, blocks, sockets, plugs, pins, alligator clips, and circuits. Standard electrical connections 111 are advantageous for using the electrical connectors 100 in various applications, such as those integrating with existing electrical circuitry.
  • the electrical connectors 100 described herein are advantageous over ordinary electrical conductors, such as copper or aluminum wire.
  • ordinary electrical conductors a high level of surface electron conduction is observed. This feature is known in the art as the skin effect.
  • the conduction electrons of the electrical connectors 100 are advantageously distributed throughout the entire volume of the electrically-conducting carbon nanotube/polymer dispersion 101 by the carbon nanotubes.
  • the carbon nanotubes comprise single-wall carbon nanotubes. In various embodiments of the electrical connectors 100, the carbon nanotubes are functionalized. In various embodiments of the electrical connectors 100, the carbon nanotubes are at least partially aligned in the electrically-conducting carbon nanotube/polymer dispersion 101.
  • Carbon nanotube alignment in the electrically-conducting carbon nanotube/polymer dispersion 101 may be accomplished by application of an electrical or magnetic field during initial dispersion of carbon nanotubes in the electrically-conducting carbon nanotube/polymer dispersion 101, during a connection of the metallic electrical conductor 102 to the electrically-conducting carbon nanotube/polymer dispersion 101, or both.
  • carbon nanotube alignment beneficially enhances the electrical conductivity and mechanical properties of the electrically-conducting carbon nanotube/polymer dispersion
  • Percolation theory predicts that there exists a percolation threshold concentration at which electrical conduction is established by a continuous carbon nanotube-to-carbon nanotube pathway. At the percolation threshold concentration, electrical conduction is established in an otherwise insulating material.
  • a weight percentage of carbon nanotubes in the electrically-conducting carbon nanotube/polymer dispersion 101 is above a percolation threshold concentration.
  • the percolation threshold concentration is an intrinsic property of various carbon nanotube/polymer dispersions. The percolation threshold concentration varies, for example, on the polymer composition and the type of carbon nanotubes used.
  • the metallic electrical conductor 102 comprises at least one metal.
  • the at least one metal may include, for example, copper, aluminum, silver, gold and combinations thereof.
  • the at least one metal may be essentially oxide free or be purified to become essentially oxide free to ensure a high level of conductance. At least a portion of the metallic electrical conductor
  • the metallic electrical conductor 102 may be coated with a substance to improve corrosion resistance, leaving at least first electrical connection point 1021 and second electrical connection point 1022 uncoated.
  • the corrosion-resistant substance provides cathodic corrosion protection, while also serving as a physical barrier between the metallic electrical conductor 102 and the environment.
  • at least a portion of the metallic electrical connector 102 is electroplated with a metal providing corrosion resistance.
  • the metallic electrical conductor 102 comprises copper, which is electroplated, at least in part, with tin.
  • any of a number of galvanically more active metals may be used for electroplating.
  • the metallic electrical conductor 102 comprises copper
  • electroplating may also be conducted with nickel, chromium or zinc.
  • Other methods such as, for example, flame metallization and hot dipping may be used to deposit the metal providing corrosion resistance.
  • the metallic electrical conductor 102 is coated with a corrosion- resistant layer that is not a metal.
  • the corrosion-resistant coating may include a polymer.
  • the at least one metal may comprise O 2 -free copper.
  • O 2 -free copper refers to a high-purity copper conductor having a very low concentration of copper oxides. Typically, O 2 -free copper has been electrolytically refined to provide oxygen levels below about 0.001%.
  • Various grades of O 2 -free copper are specified by the ASTM database. For example, O 2 -free electronic copper (ClOlOO) is 99.99% pure copper with an oxygen content of less than 0.0005%.
  • O 2 -free copper (C 10200) is 99.95% pure copper with an oxygen content of less than 0.001%.
  • the electrical connectors 100 described herein may also be constructed from electrolytic-tough-pitch copper, which has a copper purity of 99.9% and an oxygen content of 0.02 to 0.4%.
  • the metallic electrical conductor 102 may be constructed as a casting or machined block with first electrical connection point 1021 and second electrical connection point 1022 built into cavities in the block.
  • Second electrical connection point 1022 comprises a standard electrical connection 111.
  • the standard electrical connection 111 is a female connection in some embodiments.
  • the standard electrical connection 111 may be a socket.
  • the standard electrical connection 111 may be a male connection other embodiments.
  • the standard electrical connection 111 may be a plug.
  • the second electrical connection point 1022 comprises a plug as the standard electrical connection 111.
  • Standard electrical connection 111 may be attached to an existing electrical power source or standard electrical device when the electrical connector 100 is used in an application.
  • the at least one polymer is selected from the group consisting of thermoplastic and thermosetting polymers. As discussed hereinbelow, the electrical conduction properties of the electrical connectors 100 are not especially dependent on the particular polymer selected. Therefore, the at least one polymer can be selected based on fabrication and mechanical operating requirements. In various embodiments of the electrical connectors 100, the at least one polymer is selected from the group consisting of polyethylene (PE), polypropylene (PP), polyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyamide-imide (PAI), polyetherimide (PEI), polyurethane, polymethylmethacrylate, vinyl ester, epoxy, and combinations thereof.
  • PE polyethylene
  • PP polypropylene
  • PEEK polyetheretherketone
  • PEKK polyetherketoneketone
  • PAI polyamide-imide
  • PEI polyetherimide
  • the first electrical connection point 1021 contacts the electrically-conducting carbon nanotube/polymer dispersion 101.
  • the first electrical connection point 1021 may comprise a flat surface or a raised shape.
  • the raised shape may be regular or irregular and include a plurality of individual connection points. Since conducting electrons are distributed throughout the entire volume of the electrically-conducting carbon nanotube/polymer dispersion 101, rather than just residing on the outer surface as in ordinary conductors, it is advantageous to extend the electrical point of contact between electrically-conducting carbon nanotube/polymer dispersion 101 and metallic electrical conductor 102 beyond just a surface connection.
  • the first electrical connection point 1021 comprises a plurality of electrically-conducting pins 103.
  • Each of the plurality of electrically-conducting pins 103 have a diameter 120.
  • Each of the plurality of electrically-conducting pins 103 are embedded in the electrically- conducting carbon nanotube/polymer dispersion 101, which has a diameter 130.
  • Each of the plurality of electrically-conducting pins 103 may penetrate the surface of the electrically-conducting carbon nanotube/polymer dispersion 101 and embed a distance 110 within the electrically-conducting carbon nanotube/polymer dispersion 101.
  • Each of the plurality of electrically-conducting pins 103 may be cylindrical, oval, or prismatic.
  • Prismatic pins may be, for example, trigonal, tetragonal, pentagonal, hexagonal, heptagonal, octagonal, nonagonal, or decagonal.
  • the tips of the pins may be sharpened, hardened, chemically etched or a combination thereof to facilitate penetration of the electrically-conducting carbon nanotube/polymer dispersion 101.
  • Sharpening, hardening, or chemical etching modifies the shape and composition of the pins to provide for efficient flow of polymer around the plurality of electrically-conducting pins 103.
  • the plurality of electrically- conducting pins 103 have a triangular pitch to aid in penetrating the electrically- conducting carbon nanotube/polymer dispersion 101.
  • a typical arrangement of the plurality of electrically-conducting pins 103 is characterized by equidistant spacing between pins, triangular pin pitch, and uniform penetration distance 110.
  • the plurality of electrically conducting pins 103 is parallel to the direction in which at least a portion of the carbon nanotubes are aligned within the electrically-conducting carbon nanotube/polymer dispersion 101.
  • the plurality of electrically-conducting pins 103 can provide a much higher contact surface area between the first electrical connection point 1021 and the electrically-conducting carbon nanotube/polymer dispersion 101 than is achievable using a flat first electrical connection point 1021.
  • the ratio of the contact surface area of the first electrical connection point 1021 to that of the electrically-conducting carbon nanotube/polymer dispersion 101 is unity (one).
  • the ratio of the increase in surface area using a plurality of electrically-conducting pins 103 compared to a flat first electrical connection point 1021 may be calculated from the expression
  • Apjns/Ap o iym e r is the ratio of surface area of the plurality of electrically-conducting pins 103 to that of a flat first electrical connection point 1021 surface
  • N is the number of pins
  • d is the pin diameter 120 (assuming round pins)
  • L is the pin penetration depth distance 110
  • D is the diameter 130 of the contact point of the electrically-conducting carbon nanotube/polymer dispersion 101 (assuming a round contact point).
  • N is the number of pins
  • d is the pin diameter 120 (assuming round pins)
  • L is the pin penetration depth distance 110
  • D is the diameter 130 of the contact point of the electrically-conducting carbon nanotube/polymer dispersion 101 (assuming a round contact point).
  • N increases, the ratio Apins/ aceaymer also increases, and once a certain number of pins is reached, the pin surface area becomes greater than that of a flat connection surface.
  • the highest ratios of Ap ms /Ap o iymer are obtained when a large number N of pins having a small diameter 120 and long penetration depth 110 are utilized.
  • the most easily fabricated pin diameters are dictated, for example, by standard American Wire Gauges that are commercially available. One skilled in the art will recognize, however, that custom pin diameters and lengths may be fabricated which are not limited by standard American Wire Gauges.
  • the number, arrangement, diameter, and length of the plurality of electrically- conducting pins 103 may be adjusted based on the contact area required for minimal voltage drop between the electrically-conducting carbon nanotube/polymer dispersion 101 and the first electrical connection point 1021.
  • a design algorithm is presented in more detail hereinbelow, wherein physical properties of the carbon nanorubes and measured electrical properties of the electrically-conducting carbon nanotube/polymer dispersion 101 are used to determine various design parameters of the electrical connectors 100.
  • the design algorithm is based on percolation theory.
  • a ratio of pin cross-sectional area (CSA) to carbon nanotube/polymer dispersion CSA is less than about 0.01.
  • This CSA ratio is advantageous for providing smooth insertion of the plurality of electrically-conducting pins 103 into the electrically-conducting carbon nanotube/polymer dispersion 101.
  • This CSA ratio further provides for a slightly larger diameter of metallic electrical conductor 102 than the electrically-conducting carbon nanotube/polymer dispersion 101. As such metallic electrical conductor 102 can be inserted over electrically-conducting carbon nanotube/polymer dispersion 101. Advantages of this design feature for constructing electrical connectors 100 are considered hereinbelow.
  • the plurality of electrically-conducting pins 103 comprising the first electrical connection point 1021 may be the same metal as the rest of the metallic electrical conductor 102. Alternately, the plurality of electrically-conducting pins 103 comprising the first electrical connection point 1021 may be a different metal than the rest of the electrical conductor 102.
  • the metallic electrical conductor 102 may be bimetallic.
  • the plurality of electrically-conducting pins 103 may comprise at least one metal selected from a group including copper, aluminum, gold, silver, and combinations thereof.
  • the metallic electrical conductor 102 may be heated to soften the electrically-conducting carbon nanotube/polymer dispersion 101 and ease insertion of the pins. Alternately, the electrically-conducting carbon nanotube/polymer dispersion 101 may be heated directly to ease pin insertion. Electrical current may be supplied through the metallic electrical conductor 102 into electrically-conducting carbon nanotube/polymer dispersion 101 during pin insertion. Application of a current during pin insertion beneficially realigns carbon nanotubes displaced during polymer heating or pin insertion.
  • the plurality of electrically conducting pins 103 also provide mechanical strength to the connection point between the metallic electrical conductor 102 and the electrically- conducting carbon nanotube/polymer dispersion 101. When inserted into partially melted polymer of the electrically-conducting carbon nanotube/polymer dispersion 101, the plurality of pins 103 add strength to the connection point by creating an integrated phase transition zone from the electrically-conducting carbon nanotube/polymer dispersion 101 to the metallic electrical conductor 102.
  • a compression ring 106 may be fitted over the insulation 105 of the electrically-conducting carbon nanotube/polymer dispersion 101 and crimped to the carbon nanotube/polymer dispersion 101 in a first crimping operation 1071.
  • the compression ring 106 may comprise, for example, Cu/CuO.
  • the compression ring 106 may have a roughened inner surface for added adhesion to the insulation 105.
  • a second crimping operation 1072 may be performed between metallic electrical conductor 102 and electrically-conducting carbon nanotube/polymer dispersion 101.
  • Second crimping operation 1072 includes crimping the end of the metallic electrical conductor 102 down to the diameter of compression ring 106, following the first crimping operation 1071.
  • the metallic electrical conductor 102 extends at least some distance beyond the compression ring 106 following the second crimping operation 1072.
  • a third crimping operation 1073 and a fourth crimping operation 1074 are performed to crimp electrical conductor 102 to compression ring 106.
  • a protective layer 108 may be added over the completed assembly of electrical connector 100 to provide electrical insulation, mechanical shock absorbance, and corrosion resistance.
  • the protective layer 108 may be an insulating polymer, for example.
  • the protective layer 108 may be applied, for example, by heat shrinking or dip coating methods.
  • the metallic electrical conductor 102 and electrically-conducting carbon nanotube/polymer dispersion 101 may be crimped together during assembly of a completed electrical connectors 100.
  • the metallic electrical conductor 102 may be connected in a field application to an electrical power source and then connected to the electrically-conducting carbon nanotube/polymer dispersion 101 through a series of crimping operations.
  • one may cut the electrically-conducting carbon nanotube/polymer dispersion 101 with appropriate tools and then connect the metallic electrical conductor 102 by inserting the plurality of electrically-conducting pins 103 into the electrically-conducting carbon nanotube/polymer dispersion 101.
  • Adjustment of polymer viscosity and carbon nanotube alignment by heating, applying a current, or a combination thereof may be accomplished in a field application rather than directly during manufacture.
  • the electrical connectors 100 described herein embody a new paradigm in electrical conduction, certain considerations are necessary in determining various electrical design parameters.
  • carbon nanotubes are conductive at current densities up to 100 times that of Cu and other metals. Unlike metals, carbon nanotubes do not exhibit electromigration.
  • the resulting mismatch in current carrying capacity between carbon nanotubes and metallic electrical conductor 102 implies that the contact point between electrically-conducting carbon nanotube/polymer dispersion 101 and metallic electrical conductor 102 is ultimately limited by the current density of the chosen metal of the metallic electrical conductor 102.
  • the plurality of electrically-conducting pins 103 from metallic electrical conductor 102 embedded into electrically-conducting carbon nanotube/polymer dispersion 101 beneficially allows a large contact surface area to be maintained.
  • the cylindrical carbon nanotubes are generally oriented in parallel to the plurality of electrically-conducting pins 103.
  • the calculated minimum and effective contact surface area between the plurality of electrically-conducting pins 103 and the electrically-conducting carbon nanotube/polymer dispersion 101 may be determined using an algorithm described in more detail hereinbelow. Due to contact imperfections, the minimum calculated contact surface area is incrementally increased by an amount after initial calculations to provide an effective contact surface area for constructing the electrical connector 100.
  • Illustrative variables for determining the minimum and effective contact areas between metallic electrical conductor 102 and electrically-conducting carbon nanotube/polymer dispersion 101 include, for example, carbon nanotube type, carbon nanotube chirality, carbon nanotube diameter, carbon nanotube length, and a current density low enough to avoid self-heating.
  • the calculated minimum contact surface area is then adjusted upward by the volume concentration of the carbon nanotubes in the polymer to yield an effective contact surface area. Further upward refinement of the contact surface area is then performed to account for carbon nanotube misalignment in the polymer dispersion, voltage drop due to trapped polymer at the contact interface, and current density limits relative to the volume of the plurality of electrically-conducting pins 103.
  • a small degree of carbon nanotube misalignment may be beneficial in certain embodiments of the electrical connectors 100 in order to transfer current from carbon nanotube to carbon nanotube along a coherent pathway.
  • the conductivity of carbon nanotubes is thermo-electronic, rather than only electronic in nature.
  • Application of a voltage across a carbon nanotube induces various vibrational modes leading to Joule self-heating of the carbon nanotube structure.
  • Carbon nanotube electrical conductivity is strongly temperature dependent and can be described fundamentally by the temperature dependence of an electron charge carrier scattering with both acoustic and optical phonons. Phonons are quantized vibrations that carry thermal energy and alter electron equilibrium within the lattice of individual carbon nanotubes. Consequently, phonon behavior can affect many electron- dependent transport phenomena, including electrical conductivity.
  • SWNTs having metal-like conduction have zero or very small band gaps based on their (n, m) chirality indices.
  • Maximum conductivity of carbon nanotubes allows the carbon nanotubes to approach the conductivity of conducting metals, such as Cu and Al.
  • thermo-electronic model describing SWNT self-heating, electronic transport, and heat dissipation mechanisms has been described (E. Pop, D. Mann, K. E. Goodson, HJ. Dai, J. Appl. Phys. 2007:101 p. 093710).
  • the findings of this work facilitate design criteria for the electrical connectors 100 described herein.
  • the thermo-electronic model indicates that heating of SWNTs in the range of about 1 to about 10 ⁇ m in length can be limited by applying a design criterion of limiting overall power density in the electrical connectors 100.
  • methods for constructing electrical connectors comprise preparing a dispersion of carbon nanotubes in a polymer, preparing an electrical conductor comprising at least one metal, and connecting the electrical conductor and the dispersion of carbon nanotubes.
  • the carbon nanotubes in the dispersion are at least partially aligned.
  • the metallic electrical conductor comprises a first electrical connection point and a second electrical connection point.
  • the first electrical connection point comprises a plurality of electrically-conducting pins.
  • the second electrical connection point comprises a standard electrical connection.
  • the connecting step comprises inserting the plurality of electrically-conducting pins into the dispersion of carbon nanotubes. Standard electrical connections have been considered in more detail hereinabove.
  • the carbon nanotubes comprise single-wall carbon nanotubes.
  • the methods for constructing the electrical connectors further include heating the metallic electrical conductor comprising at least one metal during the connecting step. In various embodiments, the methods for constructing the electrical connectors further include heating the dispersion of carbon nanotubes during the connecting step. In various embodiments, the methods for constructing the electrical connectors further include applying an electrical current during the connecting step.
  • the at least one metal of the electrical conductor may be selected, for example, from copper, aluminum, silver, gold and combinations thereof.
  • the metallic electrical conductor is at least partially coated with a metal providing corrosion resistance. Properties of corrosion-resistant metals have been considered hereinabove.
  • the metallic electrical conductor may be formed from copper, which is essentially free of copper oxides, and then electroplated with tin.
  • metals such as, for example, nickel, zinc or chromium may be used for electroplating tin.
  • Methods for depositing the metal providing corrosion resistance are not limited to electroplating.
  • the metal providing corrosion resistance may be deposited by flame metallization or hot dipping.
  • Non-metallic corrosion-resistant coatings may also be applied to the metallic electrical conductors in the various fabrication methods.
  • a polymer may be used to coat the metallic electrical conductor.
  • the methods for constructing the electrical connectors include a series of crimping operations to connect the metallic electrical conductor to the carbon nanotube dispersion.
  • the methods for constructing the electrical connectors further include crimping a compression ring to the dispersion of carbon nanotubes.
  • the compression ring may have a roughened inner surface to provide a firm hold on the dispersion or insulation surrounding the dispersion.
  • the compression ring provides a solid structural support for further crimping operations.
  • the methods for constructing the electrical connectors further include crimping the metallic electrical connector to the dispersion of carbon nanotubes and crimping the metallic electrical conductor to the compression ring.
  • the methods for constructing the electrical connectors further include coating a protective layer over the electrical connectors.
  • the protective layer may comprise an insulating polymer layer.
  • the standard electrical connection is a male connection.
  • the standard electrical connection may be a plug.
  • the standard electrical connection is a female connection.
  • the standard electrical connection may be a socket. The choice of the standard electrical connection will ultimately be dictated by the end use of the electrical connector.
  • the methods further comprise 1) determining a percolation threshold concentration for the dispersion of carbon nanotubes; 2) fitting a power law conductivity equation using the percolation threshold concentration; 3) specifying a voltage and current to be carried by the electrical connector; 4) specifying a length of the electrical connector; 5) calculating a length and a diameter of each of the plurality of electrically conducting pins; and 6) displaying a concentration of the carbon nanotubes in the dispersion of carbon nanotubes to achieve the voltage and the current to be carried by the electrical connector.
  • the input data for example; percolation threshold concentration, voltage, current, and length; are manipulated to produce an output displayed and read by a human.
  • a human can utilize the displayed output results for constructing an electrical cable 100 having specified performance properties.
  • the input data are manipulated to produce an output displayed and read by machine.
  • the machine can automatically apply the input design parameters and output design parameters to construct an electrical cable 100 having specified performance properties.
  • methods of transmitting electrical current include providing an electrical connector described herein and connecting the electrical connector to a power source.
  • the electrical connector may be assembled prior to connecting to the power source.
  • the metallic electrical conductor of the electrical connector may be first connected to the power source, and the electrically-conducting carbon nanotube/polymer dispersion is then attached to the metallic electrical conductor through the crimping operations described hereinabove.
  • the electrical connectors provide for field assembly in various embodiments of transmitting electrical current.
  • Example 1 Fabrication of an Electrical Connector in the Form of a Cable
  • An illustrative process by which an electrical connector described hereinabove was constructed in the form of an electrical cable follows. In the illustrative example described, the electrical cable was completely assembled during the manufacturing process.
  • Electroplate Sn or other metal providing corrosion resistance on to the casting.
  • the precise number and length of the pins is determined by applying an algorithm based on the conductivity of the carbon nanotube/polymer dispersion 101 described in a subsequent example hereinbelow.
  • steps 6 and 7 drill holes into the flat face of the cavity on the second electrical contact point 1022 of the casting. Insert pins into the drilled holes by compression fitting. Solder the pins at their bases where they contact the main body of the metallic electrical conductor 102. These pins form a standard electrical connection plug. The number and arrangement of these pins is determined by the requirements of the electrical circuitry to which the electrical cable is being integrated.
  • insulating polymer sheath Place an insulating polymer sheath over the completed assembly and apply external, convective heat to shrink the sheath.
  • the insulating polymer sheath also adds support around the compression ring 106.
  • the insulating polymer sheath may be applied by dip-coating application.
  • Example 2 Evaluation of Electrical and Thermal Properties in a SWNT/Polymer Dispersion
  • the electrical connector design includes an iterative algorithm using a percolation equation, which is derived from experimental data, to confirm that the carbon nanotube concentration initially chosen will deliver a required electrical connector power load at a limiting current density.
  • the design algorithm utilizes a near-comprehensive battery of electrically-conducting carbon nanotube/polymer dispersion physical properties in determining various construction parameters of the electrical connectors.
  • the design algorithm includes carbon nanotube thermo-electronic properties, carbon nanotube geometry, carbon nanotube-to-carbon nanotube contact resistances, carbon nanotube-polymer interactions, and carbon nanotube-metallic electrical conductor 102 contact resistances.
  • the various data from real electrically-conducting carbon nanotube/polymer dispersions 101 are utilized to optimize various electrical connector
  • SWNT weight concentration to volume concentration and adjust the pin surface area upward to ensure that the pins encounter the required number of SWNTs when inserted into the SWNT/polymer dispersion. Because the SWNT/polymer dispersion and individual SWNTs are both cylindrical, the cross-sectional area fraction of SWNTs in the polymer is proportional to the volume fraction of SWNTs.
  • an electrical connector constructed as a cable is described.
  • the cable was specified for having a nominal 120 V DC (or V AC), 30 A, 3600 W SWNT-polymer conductor.
  • the SWNT/polymer dispersion was 100 ft long.
  • the SWNTs were manufactured by Southwest NanoTechnologies, Inc. (SWeNT) as Commercial Grade (CG) material and dispersed in a urethane-methacrylate polymer. Dispersion was accomplished using methods known in the art to provide sufficiently uniform polymer dispersions of carbon nanotubes.
  • SWNT concentration was incrementally varied from 0.0025 wt. % to 5.0 wt. %, and the SWNT/polymer dispersion was placed in an electrically insulating mold of uniform cross-section following processing.
  • Cu test leads were added to each end of the SWNT/polymer dispersion.
  • a DC voltage (0 - 600 V DC) was applied to the SWNT/polymer dispersion to induce an electric field and enhance alignment of the SWNTs. Voltage was applied using a constant hold, linear ramp, or cyclical sweep.
  • the electrical (Ohmic) resistance of each sample was measured both with and without applied V DC using various multimeters capable of covering a range of 1.0 x 10 "8 ⁇ to 2.1 x 10 ⁇ .
  • Raw resistance measurements were converted into volume resistivity values and then into conductivity values. These volume conductivity results were then plotted vs. SWNT concentration as shown in FIGURE 2, both in the presence and absence of an applied voltage.
  • the application of a voltage increased the conductivity of the SWNT/polymer dispersion. This effect highlights the utility of applying a voltage when connecting the SWNT/polymer dispersion and metallic electrical conductor.
  • a first derivative plot of the volume conductivity versus SWNT concentration plot was then prepared as shown in FIGURES 3 and 4, respectively, for measurements made in the presence and absence of an applied voltage.
  • the maximum values of the first derivative plots represent the percolation threshold concentration for the SWNT- urethane-methacrylate polymer dispersion. Concentrations greater than the percolation threshold concentration increased conductivity, but by an incrementally smaller amount.
  • the percolation threshold represents the aggregate effect of carbon nanotube type, size, extent of dispersion, and physico-chemical interactions with the polymer matrix. As indicated in FIGURES 3 and 4, the first derivative of conductivity reached a maximum at 0.005 wt. % SWNT, both in the presence and absence of an applied voltage.
  • the 0.005 wt. % percolation threshold is a defined property representative of the particular SWNT/polymer dispersion, and the percolation threshold is altered if either the type of carbon nanotubes or the polymer is changed.
  • the percolation equations for SWeNT CG SWNT in urethane-methacrylate polymer provide a characterization of intrinsic electrical properties vs. concentration, as well as the sensitivity of these properties to process conditions (SWNT dispersion methods, polymer curing technique, applied voltage, etc.)
  • the percolation equations were used to extrapolate the SWNT concentration predicted to achieve a target conductivity, for example, a conductivity approaching a conductive metal, such as Cu.
  • the predicted SWNT concentration should represent physical reality and not exceed certain mechanical limitations. For example, the calculated SWNT concentration to achieve a target conductivity cannot be greater than 100%. Further, the calculated SWNT concentration should not be greater than the weight percentage that the particular polymer matrix can accommodate while maintaining mechanical integrity.
  • a concentration greater than 100% or greater than the polymer's capacity to maintain mechanical integrity indicates that the SWNTs are inadequate for specified conductivity.
  • Any combination of SWNT and polymer matrix for which a percolation equation has been derived, and for which physically achievable SWNT concentrations may be realized, can be used in conjunction with the electrical connectors.
  • the electrical design method was applied to configure the electrical cable specified above (100 ft of SWNT/polymer dispersion and 3600 W power capacity).
  • the SWeNT CG SWNT concentration in urethane-methacrylate was initially specified as 5.0 wt. %.
  • An exemplary spreadsheet used for inputing and calculating various electrical connector construction parameters is shown in FIGURE 6. Parameters requiring input are indicated with darkened cells.
  • Example 4 Application of Design Algorithm in a Physically-Realistic Electrically-Conducting Cable
  • This Example describes a cable design in which the initial design specifications were within the intrinsic electrical conduction capacity of SWeNT CG SWNTs.
  • An exemplary spreadsheet used for inputing and calculating various electrical connector construction parameters is shown in FIGURE 7.
  • the cable specified in FIGURE 7 showed suitability for use in applications having a capacity of 100 V and 0.2 A, or 22 W of power.
  • a single pin penetrating 0.635 cm into a 7.62 cm SWNT/urethane- methacrylate polymer dispersion was utilized for percolation threshold concentration testing.
  • the SWNT concentration in urethane-methacrylate was 4.9 wt. % SWeNT CG SWNTs.
  • this embodiment of the electrical connector was designed to match the conductivity of SWeNT CG SWNT at a defined concentration. After setting an initial SWNT concentration of 5.0 wt. %, all design parameters were calculated. The input concentration was then iterated until the SWNT concentration output of the algorithm matched the specification. The model converged at a concentration of 4.9 wt. % SWNT and a SWNT/polymer dispersion diameter of 3.4 mm. Calculated resistivity for the electrical connector described was 6.42 ⁇ -cin versus an actual measured value of 7.54 ⁇ -cm obtained when the electrical cable was constructed and tested.
  • Example 5 Application of Design Algorithm for Common Voltages and Currents
  • FIGURE 8 A listing of various design parameters is specified in FIGURE 8. A relationship between polymer dispersion sizing and the number and gauge of pins relative to power capacity of these common voltages and currents is shown in FIGURE 9.

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Abstract

L’invention décrit des connecteurs électriques comprenant des nanotubes de carbone, au moins un polymère et un conducteur électrique métallique. Les nanotubes de carbone sont dispersés dans le polymère pour créer une dispersion polymère électriquement conductrice. Le conducteur électrique métallique est en contact avec la dispersion polymère électriquement conductrice pour former le connecteur électrique. Les connecteurs électriques comprennent les connexions électriques standards pour l’incorporation dans les applications de circuits électriques standards. L’invention décrit des procédés pour préparer les connecteurs électriques.
PCT/US2008/013428 2008-12-05 2008-12-05 Connecteurs électriques à base de nanotubes de carbone Ceased WO2010065022A1 (fr)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016025422A1 (fr) * 2014-08-11 2016-02-18 Raytheon Company Ensemble cryogenique comprenant des interconnexions électriques à nanotubes de carbone

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6146196A (en) * 1999-03-30 2000-11-14 Burger; Edward W. Mated coaxial contact system
US6683783B1 (en) * 1997-03-07 2004-01-27 William Marsh Rice University Carbon fibers formed from single-wall carbon nanotubes
WO2005109581A1 (fr) * 2004-05-06 2005-11-17 Plishner Paul J Connecteur ou autre element de circuit comprenant un circuit integre couple indirectement
WO2006060476A2 (fr) * 2004-12-01 2006-06-08 William Marsh Rice University Fibres constituees de nanotubes de carbone monoparoi obtenus par croissance epitaxiale, et procede de croissance continue et a catalyseur ajoute au niveau de l'extremite
WO2008041965A2 (fr) * 2005-08-08 2008-04-10 Cabot Corporation Compositions polymériques contenant des nanotubes
US20080251270A1 (en) * 2007-04-11 2008-10-16 Tsinghua University Coaxial cable

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6683783B1 (en) * 1997-03-07 2004-01-27 William Marsh Rice University Carbon fibers formed from single-wall carbon nanotubes
US6146196A (en) * 1999-03-30 2000-11-14 Burger; Edward W. Mated coaxial contact system
WO2005109581A1 (fr) * 2004-05-06 2005-11-17 Plishner Paul J Connecteur ou autre element de circuit comprenant un circuit integre couple indirectement
WO2006060476A2 (fr) * 2004-12-01 2006-06-08 William Marsh Rice University Fibres constituees de nanotubes de carbone monoparoi obtenus par croissance epitaxiale, et procede de croissance continue et a catalyseur ajoute au niveau de l'extremite
WO2008041965A2 (fr) * 2005-08-08 2008-04-10 Cabot Corporation Compositions polymériques contenant des nanotubes
US20080251270A1 (en) * 2007-04-11 2008-10-16 Tsinghua University Coaxial cable

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
GREGORY G WILDGOOSE ET AL: "Metal Nanoparticles and Related Materials Supported on Carbon Nanotubes: Methods and Applications", SMALL, WILEY VCH, WEINHEIM, DE, vol. 2, no. 2, 1 January 2006 (2006-01-01), pages 182 - 193, XP007907442, ISSN: 1613-6810, [retrieved on 20051219] *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016025422A1 (fr) * 2014-08-11 2016-02-18 Raytheon Company Ensemble cryogenique comprenant des interconnexions électriques à nanotubes de carbone
CN106537069A (zh) * 2014-08-11 2017-03-22 雷神公司 包括碳纳米管电连接件的低温组件

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