Circumferentially continuous fire-extinguishing dielectric sleeve

Abstract

A sleeve for protecting elongated members, including bus bars, of a battery pack, and a method of construction thereof are provided. The sleeve includes a knitted wall having a circumferentially continuous outer surface extending along a longitudinal axis between opposed open ends. The knitted wall is at least partially formed by a multifilament flame retardant yarn. The multifilament flame retardant yarn is woven to form both the knitted wall and a first rib extending longitudinally along the circumferentially continuous outer surface or a second rib extending annularly around the circumferentially continuous outer surface. An impermeable flame retardant coating is bonded to the outer surface of the circumferentially continuous knitted wall.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This PCT application claims the benefit of U.S. Provisional Patent Application No. 63 / 284,011, filed November 30, 2021, and the benefit of U.S. Provisional Patent Application No. 63 / 257,551, filed October 19, 2021, and the benefit of U.S. Provisional Patent Application No. 63 / 221,476, filed July 13, 2021, and priority to U.S. Patent Application No. 17 / 862,745, filed July 12, 2022, all of which are incorporated herein by reference in their entirety.

[0002] Background of the Invention 1.Technical Field The present invention relates generally to a knitted sleeve for protecting an elongated member contained therein, and more particularly to a circumferentially continuous, axially and radially stretchable, fire-extinguishing, dielectric knitted sleeve.

[0003] 2. Related technologies It is known to encase elongated members, such as various types of wires, wire harnesses, cables, and conduits, in circumferentially continuous tubular-walled sleeves to provide protection for the elongated members against impact and abrasion, fluid and external heat effects. However, there remains a need for a protective sleeve that can provide dielectric and fire protection for the elongated members housed therein while also achieving a low profile, has a fitted fit around the elongated members and their connectors so as to be non-cumbersome, unsightly, and bulky, is impervious to dust, particles, and fumes, and is flexible so as to be able to be routed along serpentine paths, such as bends in the elongated members, without wrinkling. There is a further need for a protective sleeve that can protect the busbar connections between the cells of the batteries in an electric vehicle battery system, allowing the vehicle to remain operable under power from the battery system for at least five minutes after a thermal runaway condition in one or more of the battery cells, to allow the driver of the electric vehicle sufficient time to safely maneuver to a suitable parking spot and vacate the vehicle.

[0004] Summary of the Invention One object of the present disclosure is to provide a textile sleeve that provides dielectric fire protection to an elongated member housed therein.

[0005] Another object of the present disclosure is to provide a stretch knit sleeve that provides dielectric fire protection to an elongated member housed therein.

[0006] Another object of the present disclosure is to provide protection to busbar connections between portions of an electric vehicle battery pack via a textile sleeve to allow the battery pack to power the electric vehicle for five minutes or more when a problem is encountered within one or more cells of the battery pack.

[0007] Another object of the present disclosure is to provide protection for busbar connections between cells of a battery pack in an electric vehicle battery system to allow sufficient time for an electric vehicle driver to safely maneuver to a suitable parking location and clear the vehicle of an overheating condition that occurs within one or more cells of the battery pack.

[0008] Another object of the present disclosure is to provide protection to busbar connections between cells of a battery pack of an electric vehicle battery system via a knitted sleeve to enable the battery system to power the electric vehicle for five minutes or more in the event of an abnormal overheating condition occurring within one or more cells of the battery pack.

[0009] Another object of the present disclosure is to provide a textile sleeve that can bend along the busbars between batteries and / or cells in an electric vehicle battery system and fit around any connectors attached to the busbars.

[0010] Another object of the present disclosure is to provide a knitted sleeve that can fit around the busbar connections between cells of a battery pack of an electric vehicle battery system in a snug-fitting relationship around the busbar and any connectors attached to the busbar.

[0011] In accordance with these and other objects, a sleeve is provided for providing protection to busbars interconnecting cells in an electric vehicle battery pack. The sleeve has a knitted wall having a circumferentially continuous outer surface extending along a longitudinal axis between opposed open ends. The knitted wall is formed at least in part from a multifilament flame-retardant yarn. The knit structure of the knitted wall is axially and radially stretchable, thereby allowing the knitted wall to be easily bent and to fit without wrinkling around a busbar, regardless of the number of bends and the shape of the outer contour of the busbar's exterior surface, for easy assembly.

[0012] In accordance with another aspect of the present invention, an impermeable coating is provided extending around the outer surface of the knitted wall to prevent the intrusion and penetration of dust, particles, and smoke through the knitted wall and to enhance the flame retardant and flame resistant protection of the sleeve.

[0013] In accordance with another aspect of the invention, the impermeable coating is stretchable to allow the underlying knitted wall to remain stretchable, thereby facilitating the formation of a snug, wrinkle-free fit in the knitted wall around the busbar.

[0014] According to another aspect of the invention, the impermeable coating is one of a silicone, silicone-based, liquid silicone rubber, polytetrafluoroethylene, or polyurethane layer bonded directly to the exterior surface of the knitted wall.

[0015] According to another aspect of the invention, the multifilament flame retardant yarn extends generally or substantially machine-wise or substantially parallel to the longitudinal axis (which may not be perfectly parallel, but close to parallel as seen by the naked eye of an observer, meaning not deviating by more than about 5 degrees from true parallel) and in a circumferential weft direction about the longitudinal axis.

[0016] According to another aspect of the present invention, the flame retardant yarn is a mineral yarn. According to another aspect of the present invention, the mineral yarn may be provided as at least one of fiberglass, silica, and basalt.

[0017] According to another aspect of the invention, the entire knit wall can be knitted from flame retardant yarn. In accordance with another aspect of the invention, the knit wall can be knitted in a rib knit pattern having raised ribs extending in one of the warp direction or the circumferential weft (fill) direction, thereby forming one of linear ribs extending in a substantially parallel relationship with the longitudinal axis or annular ribs extending circumferentially around the longitudinal axis, the ribs providing enhanced flexibility, conformability, and stretchability.

[0018] In accordance with another aspect of the present invention, a rib knit pattern may be formed by alternating knit and purl knits in a 1x1 and / or 2x2 knit pattern.

[0019] According to another aspect of the present invention, the rib knit pattern may include a smooth stitch to increase the height of the rib.

[0020] According to another aspect of the present invention, a sleeve for protecting busbar connections between portions of a battery pack system of an electric vehicle is provided. The sleeve is composed of a knitted wall having a circumferentially continuous outer surface extending along a longitudinal axis between opposed open ends and an outermost impermeable coating bonded to the outer surface of the knitted wall. The knitted wall is formed from flame-retardant multifilament yarn. The outermost impermeable coating is elastic, allowing the underlying knitted wall to remain stretchable, thereby facilitating the formation of a wrinkle-free, snug-fitting fit of the knitted wall around the busbar.

[0021] According to another aspect of the present invention, there is provided a method for constructing a sleeve for providing dielectric protection for busbar interconnections in an electric vehicle battery pack. The method includes knitting a multifilament flame-retardant yarn to form a knitted wall having a circumferentially continuous outer surface extending along a longitudinal axis between opposing open ends. The method further includes forming a plurality of first ribs extending longitudinally in a generally parallel relationship with the longitudinal axis within the knitted wall, or forming a plurality of second ribs extending circumferentially around the longitudinal axis within the knitted wall.

[0022] According to another aspect of the invention, the method may further include bonding an impermeable coating to the outer surface of the knitted wall.

[0023] According to another aspect of the invention, the method may further include bonding an impermeable coating having a uniform thickness over the entire knitted wall.

[0024] According to another aspect of the invention, the method may further include forming the impermeable coating from one of a silicone, silicone-based, liquid silicone rubber, polytetrafluoroethylene, or polyurethane layer.

[0025] According to another aspect of the invention, the method may further include providing the multifilament flame retardant yarn from at least one of glass fiber, silica, and basalt.

[0026] According to another aspect of the invention, the method may further include forming the first rib and the second rib by alternating knitting and purl knitting.

[0027] According to another aspect of the invention, the method may further include knitting the first ribs in substantially equidistant spaced relationship to one another or knitting the second ribs in substantially equidistant spaced relationship to one another.

[0028] According to another aspect of the invention, the method may further include knitting the entire knit wall from mineral yarn.

[0029] According to another aspect of the present invention, a sleeve for providing protection to busbar interconnections, such as adjacent cells and / or adjacent battery modules in an electric vehicle battery pack, is provided. The sleeve has a textile wall having a circumferentially continuous outer surface extending along a longitudinal axis between opposed open ends. The textile wall is formed at least in part by a multifilament flame-retardant yarn interwoven with a shrinkage yarn. The shrinkage yarn is configured to shrink the continuous outer surface from a first diameter to a reduced second diameter, thereby forcing the textile wall into a snug relationship with the busbar.

[0030] In accordance with another aspect of the invention, the outer surface of the textile wall exhibits a convoluted profile to enhance the flexibility of the textile wall, allowing the textile wall to bend freely along the bend in the bus bar and fit around the connector of the bus bar without twisting.

[0031] In accordance with another aspect of the invention, an impermeable coating may be provided that extends around the outer surface of the textile wall.

[0032] According to another aspect of the invention, the impermeable coating is one of a silicone, silicone-based, liquid silicone rubber, polytetrafluoroethylene, or polyurethane layer bonded directly to the outer surface of the textile wall.

[0033] According to another aspect of the invention, the textile wall can be woven. According to another aspect of the invention, the multifilament flame retardant yarns extend in a warp direction generally parallel to the longitudinal axis of the textile wall and in a circumferential weft direction about the longitudinal axis, and the shrinkage yarns extend only in the circumferential direction about the longitudinal axis.

[0034] According to another aspect of the invention, the textile wall can be knitted. According to another aspect of the invention, textile walls can be constructed.

[0035] According to another aspect of the present invention, the shrink yarn is heat shrinkable. According to another aspect of the present invention, a sleeve for protecting busbar connections between cells and / or battery modules in an electric vehicle battery pack is provided. The sleeve is composed of a tubular textile wall having a circumferentially continuous outer surface extending along a longitudinal axis between opposite open ends. The textile wall is formed from a flame-retardant multifilament yarn interwoven with a shrinkage yarn, the shrinkage yarn being configured to shrink the continuous outer surface from a first diameter to a reduced second diameter.

[0036] According to another aspect of the invention, the shrinking yarn is configured to shrink the continuous outer surface to form a tubular textile wall having a convoluted profile formed by alternating circumferentially extending peaks and valleys along its length.

[0037] According to another aspect of the invention, a method of constructing a sleeve for providing dielectric protection to a busbar interconnection, such as adjacent cells and / or adjacent battery modules of an electric vehicle battery pack, is provided. The method includes interweaving a multifilament flame-retardant yarn to form a textile wall having a circumferentially continuous outer surface extending along a longitudinal axis between opposed open ends, and interweaving a shrinkage yarn with the multifilament flame-retardant yarn, the shrinkage yarn configured to shrink the continuous outer surface from a first diameter to a reduced second diameter into a snug fit with the busbar.

[0038] According to another aspect of the invention, the method can include configuring a shrinking thread to shrink the continuous outer surface to form a continuous outer surface having a convoluted profile formed by alternating circumferentially extending peaks and valleys along its length.

[0039] According to another aspect of the invention, the method may further include bonding a flexible, high temperature resistant, impervious coating to an outer surface of the textile wall.

[0040] BRIEF DESCRIPTION OF THE DRAWINGS These and other aspects, features, and advantages will become readily apparent to those skilled in the art upon consideration of the following detailed description of the presently preferred embodiments and best mode, the appended claims, and the accompanying drawings. [Brief explanation of the drawings]

[0041] [Figure 1] 1 is a perspective view of a vehicle having a knitted sleeve constructed in accordance with one aspect of the present disclosure shown positioned around an electric vehicle battery component to be protected; [Figure 2]FIG. 1 is an enlarged, partial schematic perspective view of a knitted sleeve according to one aspect of the present disclosure shown positioned around an elongated member to be protected by the textile sleeve. [Figure 2A] FIG. 10 is an enlarged, partial schematic perspective view of a knitted sleeve according to another aspect of the present disclosure shown positioned around an elongated member to be protected by the textile sleeve. [Figure 3] FIG. 3 is an enlarged schematic cross-sectional view taken generally along line 3-3 of FIG. 2. [Figure 4A] FIG. 1 is a perspective view of a knitted sleeve before it is coated, with the knitted sleeve shown positioned around a busbar. [Figure 4B] 4B is a view similar to FIG. 4A, showing an impermeable coating applied to the outer surface of the knitted wall of FIG. 4A. [Figure 5] FIG. 10 is an enlarged, partial schematic perspective view of a textile sleeve constructed in accordance with another aspect of the present disclosure shown positioned around an elongated member to be protected with the textile sleeve shown in its manufactured, uncontracted state. [Figure 5A] FIG. 6 is a view similar to FIG. 5, but showing the textile sleeve in a contracted state. [Figure 6] FIG. 6 is an enlarged schematic cross-sectional view taken generally along line 6-6 of FIG. 5. [Figure 6A] FIG. 6A is an enlarged schematic cross-sectional view taken generally along line 6A-6A of FIG. 5A. [Figure 7A] FIG. 1 is a schematic plan view of the textile layers of a sleeve showing that the innermost textile layer is woven according to one embodiment of the present disclosure. [Figure 7B] 7B is a view similar to FIG. 7A showing the textile layers braided according to another embodiment of the present disclosure. [Figure 7C] FIG. 7B is a view similar to FIG. 7A showing the textile layer woven in accordance with yet another embodiment of the present disclosure. [Figure 8]FIG. 10 is an enlarged, partial schematic perspective view of a textile sleeve constructed in accordance with another aspect of the present disclosure shown positioned around an elongated member to be protected with the textile sleeve shown in its manufactured, uncontracted state. [Figure 9] 9 is a view similar to FIG. 8, but showing the textile sleeve in a contracted state. [Figure 10] 10 is an enlarged schematic cross-sectional view taken generally along line 10-10 of FIG. 8. [Figure 10A] 10A is an enlarged schematic cross-sectional view taken generally along line 10A-10A of FIG. 9. [Figure 11A] FIG. 1 is a schematic plan view of the textile layers of a sleeve showing that the innermost textile layer is woven according to one embodiment of the present disclosure. [Figure 11B] 11B is a view similar to FIG. 11A showing the textile layers braided according to another embodiment of the present disclosure. [Figure 11C] FIG. 11B is a view similar to FIG. 11A showing the textile layer knitted according to yet another embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0042] Detailed Description of the Preferred Embodiments Referring more particularly to the drawings, FIG. 1 illustrates a protective textile sleeve, hereinafter referred to as sleeve 10, constructed in accordance with one embodiment of the present invention having a textile knit wall 12 disposed around elongated members 11 to be protected from one another, such as busbar interconnections between adjacent cells and / or cell modules of a battery pack, hereinafter referred to as battery B, of a vehicle, such as an electric vehicle (EV). Knit wall 12 has a seamless, circumferentially continuous outer surface 13 extending longitudinally between open, opposing ends 14, 16 and about a longitudinal center axis 18 to bound a central cavity 20. Elongated members 11 extend through central cavity 20 and are protected within the central cavity by knit wall 12 against impact forces, such as those that may be encountered during a vehicle collision, abrasion, and contamination intrusion, by way of example and not limitation. The knitted wall 12 suppresses flame propagation, such as in the event of thermal runaway of one or more of the cells of battery B, thereby allowing the electric vehicle EV to remain powered by the battery for five minutes or more to allow the electric vehicle EV to be safely driven to a parking location so that the driver can evacuate the electric vehicle EV. The knitted wall 12 is formed at least partially or entirely from flame-retardant multifilament yarn 22 knitted in a rib knit pattern to increase the elasticity and stretchability of the wall 12 and facilitate assembly of the sleeve 10 around the elongated member 11. A plurality of ribs (R) are formed by alternating face knitting and purl knitting in a desired pattern, such as, by way of example and not limitation, 1×1, 2×2, etc., to form first longitudinally (warp) extending ribs R ( FIG. 2 ) or second circumferentially (weft or fill) extending ribs R ( FIG. 2A ), facilitating a wrinkle-free, snug-fitting fit of knit wall 12 around busbar 11, thereby facilitating assembly and flame suppression, having a low profile, and being aesthetically appealing. Thus, the knit structure of knit wall 12 is stretchable axially and radially (circumferentially), thereby allowing knit wall 12 to flex and be easily assembled into a tight, snug-fitting relationship around busbar 11.

[0043] To further enhance the flame resistance, stretchability, and resilience of sleeve 10, impermeable coating 26 is provided extending around outer surface 13 of knitted wall 12 to prevent the intrusion and penetration of dust, particles, and smoke through knitted wall 12 and enhance the flame resistance and flame protection of sleeve 10. Impermeable coating 26 is elastically stretchable and elastically resilient in all directions, including longitudinally and radially, to allow underlying knitted wall 12 to remain stretchable along longitudinal and radial directions, thereby facilitating a wrinkle-free, snug-fitting fit of knitted wall 12, and ultimately sleeve 10, around busbar 11.

[0044] When subjected to an excessive heat scenario, such as during an unintended thermal runaway condition in a battery, the flame-retardant multifilament yarns 22 retain their structural integrity to inhibit flame growth and propagation for at least five minutes or more, thereby allowing sufficient time for occupants of the automobile EV to park and / or evacuate the automobile EV.

[0045] An impermeable coating 26, such as a silicone, silicone-based, liquid silicone rubber, polytetrafluoroethylene, or polyurethane coating, can be applied and bonded to the exterior surface 13, and the coating 28, also referred to as a layer, is bonded directly to the exterior surface 13. The impermeable layer 26 can be applied to the exterior surface 13 using any desired process that allows the desired thickness (t) of the layer 26 to be achieved. In an exemplary embodiment, the thickness t is approximately 0.05 to 3 mm, more preferably approximately 0.1 to 0.3 mm. When the layer 26 is applied within the aforementioned range of thickness t, the flexibility and conformability of the wall 12 are optimized and optimal dielectric strength is provided, which can provide a breakdown voltage of approximately 5 to 40 kV. Therefore, the elongated member 11 is protected from undesirable electrical interference, including electromagnetic interference (EMI), radio frequency interference (RFI), and electrostatic discharge (ESD). In addition to various electrical protections, the layer 26 can provide significantly enhanced protection for the elongated member 11 against impact forces. Furthermore, considering that layer 26 can be hydrophobic and impermeable to fluids and debris, enhanced protection is provided against the ingress of contaminants such as fluid gases and solid debris.

[0046] According to another aspect, a method of constructing a thermal protection sleeve 10 is provided. The method includes knitting a multifilament flame-retardant yarn to form a textile wall 12 having a circumferentially continuous outer surface 13 extending along a longitudinal axis 18 between opposed open ends 14, 16. The method may further include knitting the multifilament flame-retardant yarn using a rib knit pattern to form a first rib R ( FIG. 2 ) extending lengthwise along the longitudinal axis 18 of the sleeve 10, or a second rib R ( FIG. 2A ) extending annularly circumferentially around the longitudinal axis 18 of the sleeve 10, the rib R increasing the flame resistance of the wall 12 while also increasing the stretchability of the wall 12 in both the radial and axial directions.

[0047] According to another aspect of the present invention, the method may further include bonding an impermeable coating 26 to the outer surface 13 of the textile wall 12, the impermeable coating 26 being formed from an elastomeric material to enhance the stretch and recovery of the sleeve 10.

[0048] According to another aspect of the invention, the method may further include forming the impermeable coating 26 from a resilient, stretchable silicone, silicone-based, liquid silicone rubber, polytetrafluoroethylene, or polyurethane material.

[0049] 5-7B illustrate a textile sleeve, hereafter referred to as sleeve 110, constructed in accordance with one embodiment of the present invention having a textile wall 112 disposed around elongated members 111 to be protected from one another, such as busbar-interconnected batteries B of a vehicle, such as an electric vehicle (EV). The textile wall 112 has a seamless, circumferentially continuous outer surface 113 extending longitudinally between open, opposing ends 114, 116 and around a longitudinal central axis 118 to bound a central cavity 120 through which the elongated members 111 extend, where the elongated members 111 are protected from impact forces, such as those that may be encountered in a vehicle crash, abrasion, and contamination ingress. The wall 112 suppresses flame propagation, such as in the event of thermal runaway of one or more of the batteries, thereby allowing the electric vehicle to remain powered by batteries B for five or more minutes to allow the electric vehicle to be safely driven to a parking spot, thereby allowing the driver to evacuate the electric vehicle. The textile wall 112 is formed from flame-retardant multifilament yarns 122 interwoven with shrinkage yarns 124, which cause the continuous outer surface 113 to shrink from a first diameter D1 ( FIG. 6 ) to a reduced second diameter D2 ( FIG. 6A ) into a snug, conforming relationship around the contours of the elongated member 111, thereby facilitating flame suppression, having a low profile, and being aesthetically appealing. It should be understood that shrinking the sleeve 110 from the first diameter D1 to the second diameter D2 can cause the sleeve 111 to assume a shape other than circular, and can shrink around any underlying contour shape, such as, by way of example and not limitation, a rectangle ( FIG. 6A ), to conform to a close, snug fit around the generally rectangular cross-sectional shape of a known busbar 111. Thus, shrinking the sleeve 110 can conform to a non-circular contour, as illustrated by shrinking across the outer diameter D2 and inner diameter D2′ of the busbar 111 shown in FIGS. 6 and 6A . This is particularly useful when shrinking around electrical connectors and the like, such as, by way of example and not limitation, around the terminals T of a vehicle battery B.

[0050] The textile wall 112 is one of a circumferentially continuous, tubularly constructed woven wall ( FIG. 7A ), braided wall ( FIG. 7B ), or knitted wall ( FIG. 7C ). It will be appreciated by those skilled in the art that a minimum amount of shrink yarn 124 sufficient to bring wall 112 from its expanded, assembled state ( FIGS. 5 and 6 ) to its final, assembled, contracted state ( FIGS. 5A and 6A ) may be used. When subjected to an excessive heat scenario, such as during an unintended thermal runaway condition of one or more of the cells of Battery B, the shrink yarn 124 may burn out or significantly burn due to the excessive heat, while the flame-retardant multifilament yarn 122 maintains their structural integrity to suppress flame growth and propagation for at least five minutes or more, thereby allowing sufficient time for occupants of the automobile EV to park and / or evacuate the automobile EV.

[0051] An impermeable coating 126, such as a silicone, silicone-based, liquid silicone rubber, polytetrafluoroethylene, or polyurethane coating, can be applied to and bonded to the exterior surface 113, also referred to as a layer, and is bonded directly to the exterior surface 113. The impermeable layer 126 can be applied to the exterior surface 113 using any desired process that allows the desired thickness (t) of the layer 126 to be achieved. In an exemplary embodiment, the thickness t is approximately 0.05 to 3 mm, more preferably approximately 0.1 to 0.3 mm. When the layer 126 is applied within the aforementioned range of thickness t, the wall 112 remains flexible and conformable while providing optimal dielectric strength, which can provide a breakdown voltage of approximately 5 to 40 kV. Thus, the elongated member 111 is protected from undesirable electrical interference, including electromagnetic interference (EMI), radio frequency interference (RFI), and electrostatic discharge (ESD). In addition to various electrical protections, the layer 126 can provide significantly enhanced protection for the elongated member 111 against impact forces. Furthermore, given that layer 126 can be hydrophobic and impervious to fluids and debris, enhanced protection against the ingress of contaminants such as fluids and solids is provided.

[0052] According to another aspect, a method of constructing a sleeve 110 is provided. The method includes interweaving multifilament flame-retardant yarns to form a textile wall 112 having a circumferentially continuous outer surface 113 extending along a longitudinal axis 118 between opposed open ends 114, 116, and interweaving the multifilament flame-retardant yarns 122 with shrinkage yarns 124, the shrinkage yarns 124 configured to shrink the circumferentially continuous outer surface 113 from a first diameter D1 to a reduced second diameter D2, D2′ (including non-circular shapes, as described above) in a snug, mating relationship with the busbar 111.

[0053] According to another aspect of the invention, the method may further include bonding an impermeable coating 126 to the outer surface 113 of the textile wall 112 .

[0054] According to another aspect of the present invention, the method may further include weaving the multifilament flame retardant yarn 122 and the shrink yarn 124 to form a textile wall.

[0055] According to another aspect of the present invention, the method may further include braiding the multifilament flame-retardant yarn 122 and the shrink yarn 124 to form the textile wall 112 .

[0056] According to another aspect of the present invention, the method may further include knitting the multifilament flame retardant yarn 122 and the shrink yarn 124 to form the textile wall 112 .

[0057] 8 illustrates a textile sleeve, hereafter referred to as sleeve 210, constructed in accordance with another embodiment of the present invention having a textile wall 212 disposed around elongated members 211 to be protected from one another, such as busbar-interconnected cells of a battery B of a vehicle such as an electric vehicle EV. Textile wall 212 has a seamless, circumferentially continuous outer surface 213 that extends longitudinally between open opposing ends 214, 216 and around a central longitudinal axis 218 to bound a central cavity 220. Elongated members 211 extend through central cavity 220 and are protected within the central cavity by wall 212 against impact forces, such as those that may be encountered during a vehicle collision, abrasion, and contamination intrusion, by way of example and not limitation. Wall 12 suppresses flame propagation, such as in the event of thermal runaway of one or more of the battery's cells, thereby allowing the electric vehicle to remain powered by the battery for five minutes or more to allow the electric vehicle to be safely driven to a parking spot so the driver can evacuate the electric vehicle. Textile wall 212 is formed from flame-retardant multifilament yarn 222, including monofilament or multifilament, interwoven with shrinkage yarn 224, which is configured to compress and shrink circumferentially extending discontinuous regions 225 axially spaced from one another along longitudinal axis 218 from an uncontracted state ( FIG. 10 ) to a contracted state ( FIGS. 9 and 10A ) to form a seamless, continuous outer surface 213 having a convoluted profile formed by alternating peaks P and valleys V. The constricted discontinuous regions 225 thereby force the wall 213 into a snug, conforming relationship around the contours of the elongated member 211, thus facilitating flame suppression, having a low profile, and being aesthetically appealing. It should be understood that the constriction of the sleeve 210 can be around any geometric shape, including circular and non-circular busbars 211, when viewed in cross section. As such, the constriction of the sleeve 210 can conform to non-circular contours, such as illustrated by the constriction across the outer diameter D2 and inner diameter D2' of the busbar 211 shown in FIGS. 9 and 10A. This is particularly useful when constricting around irregularly shaped electrical connectors, for example and without limitation.It should be further appreciated that the convoluted profile provided by the peaks P and valleys V increases the flexibility of the sleeve 210, thereby allowing the sleeve 210 to be routed along a serpentine path without twisting, while also increasing its impact resistance via the peaks P.

[0058] The textile wall 212 is one of a circumferentially continuous, tubularly constructed woven wall ( FIG. 11A ), braided wall ( FIG. 11B ), or knitted wall ( FIG. 11C ). It will be appreciated by those skilled in the art that a minimum amount of shrinkage yarns 224 sufficient to form a desired number and width of valleys V along the wall 212 can be used. It should be appreciated that the individual widths of the valleys V can be provided as desired, and the widths can be the same or different from one another, as desired, by providing the same number of circumferentially extending shrinkage yarns 224 in the discontinuous regions 225 to provide valleys V having the same width relative to one another, or different numbers of circumferentially extending shrinkage yarns 224 to provide at least some of the discontinuous regions 225 and resulting valleys V having various different widths relative to one another, as desired. When subjected to an excessive heat scenario, such as during an unintended thermal runaway condition of one or more cells of the battery, the shrink yarns 224 may burn out or significantly burn due to the excessive heat, while the flame-retardant multifilament yarns 222 retain their structural integrity to suppress flame growth and propagation for at least five minutes or more, thereby allowing sufficient time for occupants of the automobile EV to park and / or evacuate the automobile EV.

[0059] An impermeable fire-resistant coating, also referred to as a solid layer or layer 226, such as a silicone, silicone-based, liquid silicone rubber, polytetrafluoroethylene, or polyurethane coating, can be applied to and bonded to exterior surface 213, also referred to as a layer, directly bonded to exterior surface 213. Impermeable layer 226 can be applied to exterior surface 213 using any desired process that allows a preferred thickness (t) of layer 226 (FIG. 10) to be achieved. In an exemplary embodiment, thickness t is approximately 0.05 to 3 mm, more preferably approximately 0.1 to 0.3 mm. When layer 226 is applied within the aforementioned range of thickness t, wall 212 remains flexible and conformable while providing optimal dielectric strength, which can provide a breakdown voltage of approximately 5 to 40 kV. Thus, elongated member 211 is protected from undesirable electrical interference, including electromagnetic interference (EMI), radio frequency interference (RFI), and electrostatic discharge (ESD). In addition to various electrical protection, significantly enhanced protection for elongate member 211 against impact forces may be provided by layer 226. Furthermore, considering that layer 226 may be hydrophobic and impervious to fluids and debris, enhanced protection against the ingress of contaminants such as fluids and solids is provided.

[0060] According to another aspect, a method of constructing a sleeve 210 is provided. The method includes interweaving multifilament flame-retardant yarns 222 to form a textile wall 212 having a seamless, circumferentially continuous outer surface 213 extending along a longitudinal axis 218 between opposed open ends 214, 216, and interweaving the multifilament flame-retardant yarns 222 with selectively positioned contraction yarns 224, the contraction yarns 224 configured to compress and contract circumferentially extending annular discontinuous regions 225 of the textile wall 212, axially spaced from one another along the longitudinal axis 218, to form the continuous outer surface 213 having a convoluted profile formed by alternating multiple peaks P and multiple valleys V. The peaks P are formed predominantly or entirely from the multifilament flame-retardant yarns 222, and the valleys V are formed predominantly or entirely from the contraction yarns 224 in the weft direction, with the multifilament flame-retardant yarns 222 extending therethrough in the warp direction. Therefore, the weft direction yarns forming the valleys V can be provided over the entire contraction yarn 224.

[0061] According to another aspect of the invention, the method may further include bonding an impermeable coating 226 to the outer surface 213 of the textile wall 212 .

[0062] According to another aspect of the present invention, the method may further include weaving the multifilament flame retardant yarn 222 and the shrink yarn 224 to form the textile wall 212 .

[0063] According to another aspect of the present invention, the method may further include braiding the multifilament flame retardant yarn 222 and the shrink yarn 224 to form the textile wall 212 .

[0064] According to another aspect of the present invention, the method may further include knitting the multifilament flame retardant yarn 222 and the shrink yarn 224 to form the textile wall 212 .

[0065] Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is contemplated that all features of all claims and all embodiments may be combined with each other unless such combinations are mutually inconsistent. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

Claims

1. A sleeve for protecting an elongated member, comprising: A knitted wall having a circumferentially continuous outer surface extending along a longitudinal axis between opposed open ends, the knitted wall being formed at least in part by a multifilament flame-retardant yarn interwoven with a shrinkage yarn, the multifilament flame-retardant yarn being knitted to form a first rib extending longitudinally along the circumferentially continuous outer surface or a second rib extending annularly around the circumferentially continuous outer surface. A sleeve comprising:

2. The sleeve of claim 1 , further comprising an impermeable coating extending around the circumferentially continuous outer surface of the knitted wall.

3. 3. The sleeve of claim 2, wherein the impermeable coating is one of a silicone, silicone-based, liquid silicone rubber, polytetrafluoroethylene, or polyurethane layer bonded directly to the circumferentially continuous outer surface of the knitted wall.

4. A sleeve as described in claim 1, wherein the plurality of first ribs and second ribs are formed by alternating knitting and purl knitting in a desired pattern.

5. The sleeve of claim 2 , wherein the multifilament flame retardant yarn is a mineral yarn.

6. The sleeve of claim 5 , wherein the mineral yarn is at least one of fiberglass, silica, and basalt.

7. The sleeve of claim 5 , wherein the knit wall is formed entirely from the mineral yarn.

8. The sleeve of claim 1 , wherein the knitted wall is configured to be placed around a bus bar of a battery pack of an electric vehicle.

9. 1. A sleeve for protecting busbar connections between battery packs of an electric vehicle, comprising: a knitted wall having a circumferentially continuous outer surface extending along a longitudinal axis between opposed open ends, said knitted wall being formed at least in part by a multifilament flame retardant yarn interwoven with a shrinkage yarn, said multifilament flame retardant yarn being knitted to form one of a first rib R extending longitudinally in a generally parallel relationship with said longitudinal axis, or a second rib R extending circumferentially about said longitudinal axis; and an impermeable coating extending around the outer surface of the knitted wall; A sleeve consisting of:

10. 10. The sleeve of claim 9, wherein the impermeable coating is one of a silicone, silicone-based, liquid silicone rubber, polytetrafluoroethylene, or polyurethane layer bonded directly to the circumferentially continuous outer surface of the knitted wall.

11. A sleeve as described in claim 9, wherein a plurality of the first ribs and the second ribs are formed by alternating knitting and purl knitting in a desired pattern.

12. The sleeve of claim 9, wherein the multifilament flame retardant yarn is a mineral yarn.

13. The sleeve of claim 12 , wherein the mineral yarn is at least one of fiberglass, silica, and basalt.

14. The sleeve of claim 12 , wherein the knit wall is formed entirely from the mineral yarn.

15. 1. A method of constructing a sleeve for providing dielectric protection for busbar interconnections of an electric vehicle battery pack, comprising: knitting a multifilament flame retardant yarn interwoven with a shrinkable yarn to form a knit wall having a circumferentially continuous outer surface extending along a longitudinal axis between opposed open ends; forming a plurality of first ribs extending longitudinally in a generally parallel relationship with the longitudinal axis within the knitted wall or a plurality of second ribs extending circumferentially around the longitudinal axis within the knitted wall; A method comprising:

16. The method of claim 15 further comprising bonding an impervious coating to the circumferentially continuous outer surface of the knitted wall.

17. 17. The method of claim 16, further comprising forming the impermeable coating from one of a silicone, silicone-based, liquid silicone rubber, polytetrafluoroethylene, or polyurethane material.

18. 17. The method of claim 16, further comprising forming the first rib and the second rib by alternating knitting and purl knitting.

19. 17. The method of claim 16, further comprising providing the multifilament flame retardant yarn as a mineral yarn and knitting the entire knit wall from the mineral yarn.

20. 16. The method of claim 15, further comprising knitting the first ribs in substantially equidistant spaced relation to one another or knitting the second ribs in substantially equidistant spaced relation to one another.

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