Mounting opening seals for vehicle battery sets

Abstract

According to a non-restrictive example, a battery pack for a vehicle comprises a housing that includes a base, a plurality of side walls, and a cover extending over the plurality of side walls. The cover includes an outer surface section and an inner surface section, and an opening extending through both the outer and inner surface sections. A grommet having a central opening is arranged in the opening. The grommet includes a first section engaging the outer surface section, a second section engaging the inner surface section, and a connecting section joining the first and second sections. A pressure relief valve having a through-pass is mounted in the central opening of the grommet.The pressure limiter comprises a flange surrounded by the first section of the nozzle and a support section extending through the connecting section to the second section of the nozzle.

Description

INTRODUCTION

[0001] The subject matter of the disclosure relates to the state of the art in vehicle battery packs and, in particular, to the mounting hole seal for a vehicle battery pack.

[0002] Vehicle battery packs consist of a housing that surrounds multiple battery modules enclosing battery cells. The housing includes a sealed cover. The battery pack is mounted inside the vehicle through the cover. Generally, the battery pack is positioned underneath the vehicle and against a lower surface. Fasteners are threaded from the vehicle interior through a vehicle floor, through the cover, and connected to the battery pack. Once tightened, the battery pack is secured to the vehicle.

[0003] After manufacturing and before transport to an assembly facility, a vacuum is created within the enclosure. This vacuum is part of an end-of-line vacuum test of the enclosure and ensures that the battery pack is properly sealed for shipping. Openings in the cover that accommodate the fasteners make it difficult to create a vacuum for shipping. Accordingly, it is desirable to provide a seal that closes the openings to allow a vacuum within the enclosure while still allowing passage for mechanical fasteners to mount the battery pack to the vehicle. SUMMARY

[0004] A battery pack for a vehicle, according to one non-limiting example, includes a housing including a base, a plurality of sidewalls, and a cover extending over the plurality of sidewalls. The cover includes an outer surface portion and an inner surface portion and an opening extending through the outer surface portion and the inner surface portion. A grommet having a central opening is disposed in the opening. The grommet includes a first portion engaging the outer surface portion, a second portion engaging the inner surface portion, and a connecting portion connecting the first portion and the second portion. A pressure limiter having a passageway is mounted in the central opening of the grommet.The pressure limiter comprises a flange surrounded by the first section of the nozzle and a support section extending through the connecting section to the second section of the nozzle. A plug is arranged in the passage.

[0005] In addition to one or more of the features described herein, a connecting element is disposed between the housing and the cover, the connecting element including a threaded passage aligned with the opening in the cover.

[0006] In addition to one or more of the features described herein, the support portion of the pressure element abuts the connecting element.

[0007] In addition to one or more of the features described herein, the first portion of the grommet comprises a first thickness and the flange comprises a second thickness different from the first thickness.

[0008] In addition to one or more of the features described herein, the first thickness is greater than the second thickness.

[0009] In addition to one or more of the features described herein, the flange of the pressure limiter includes an annular recess, the first portion of the grommet overlapping the annular recess.

[0010] In addition to one or more of the features described herein, the grommet is formed from an elastic material.

[0011] In addition to one or more of the features described herein, the pressure limiter is formed from an inelastic material.

[0012] In addition to one or more of the features described herein, the inelastic material comprises one of a metal and a metal alloy.

[0013] In addition to one or more of the features described herein, the plug is formed from a self-healing, pierceable elastic material.

[0014] A vehicle, according to one non-limiting example, includes a body defining a passenger compartment having a floor including an interior surface and an exterior surface. A battery pack is mounted to the exterior surface of the floor. The battery pack includes a housing including a plurality of sidewalls and a cover extending over the plurality of sidewalls. The cover includes an outer surface portion and an interior surface portion and an opening extending through the outer surface portion and the interior surface portion. A grommet having a central opening is disposed in the opening. The grommet includes a first portion engaging the exterior surface portion, a second portion engaging the interior surface portion, and a connecting portion connecting the first portion and the second portion.A pressure limiter having a passageway is mounted in the central opening of the grommet. The pressure limiter includes a flange surrounded by the first portion of the grommet and a support portion extending through the connecting portion to the second portion of the grommet. A plug is disposed in the passageway. A fastener extends through the base into the plug. The fastener secures the battery pack to the outer surface of the base.

[0015] In addition to one or more of the features described herein, a connecting element is disposed between the housing and the cover. The connecting element includes a threaded passage aligned with the opening in the cover. The fastening element extends through the plug into engagement with the threaded passage.

[0016] In addition to one or more of the features described herein, the support portion of the pressure element abuts the connecting element.

[0017] In addition to one or more of the features described herein, the first portion of the grommet comprises a first thickness and the flange comprises a second thickness different from the first thickness.

[0018] In addition to one or more of the features described herein, the first thickness is greater than the second thickness.

[0019] In addition to one or more of the features described herein, the flange of the pressure limiter includes an annular recess, the first portion of the grommet overlapping the annular recess.

[0020] In addition to one or more of the features described herein, the grommet is formed from an elastic material.

[0021] In addition to one or more of the features described herein, the pressure limiter is formed from an inelastic material.

[0022] In addition to one or more of the features described herein, the inelastic material comprises one of a metal and a metal alloy.

[0023] In addition to one or more of the features described herein, the plug is formed from a self-healing, pierceable elastic material.

[0024] The above features and advantages, as well as other features and advantages of the disclosure, will be readily apparent from the following detailed description when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Further features, advantages and details are listed only as examples in the following detailed description, which refers to the drawings, where: Fig. 1 is a left side view of a vehicle having a battery pack including mounting port seals, according to one non-limiting example; Fig. 2 a perspective view of a battery pack of Fig. 1, comprising a plurality of mounting hole seals, according to a non-limiting example; Fig. 3 is a cross-sectional side view of a portion of a battery pack connected to the vehicle, according to a non-limiting example; Fig. 4 is a perspective view of a mounting hole seal, according to a non-limiting example; Fig. 5 is a cross-sectional view of a mounting hole seal used in a cover of the battery pack of Fig. 2 is mounted; and Fig. 6 a perspective view of the mounting hole seal of Fig. 4, according to a non-limiting example. DETAILED DESCRIPTION

[0026] The following description is merely exemplary and is not intended to limit the present disclosure, its application, or uses. It should be understood that throughout the drawings, corresponding reference characters designate like or corresponding parts and features.

[0027] A vehicle according to a non-limiting example is in Fig. 1, generally indicated at 10. The vehicle 10 includes a body 12 supported on a plurality of wheels 16. The body 12 partially defines a passenger compartment 20 having seats 23 positioned behind an instrument panel 26. A steering controller 30 is disposed between the seats 23 and the instrument panel 26. The steering controller 30 is actuated to control the orientation of the steerable wheel(s). The vehicle 10 includes an electric drive motor 34 that provides power to one or more of the plurality of wheels 16.

[0028] A rechargeable energy storage system (RESS) or battery pack 38 is mounted on the body 12. The battery pack 38 provides power to the electric drive motor 34. At this point, it should be understood that the location of the electric drive motor 34 and the battery pack 38 within the vehicle 10 may vary. In one non-limiting example, the passenger compartment 20 includes a floor 40 having an interior surface 42 and an exterior surface 44 ( Fig. 3). As explained in more detail below, the battery pack 38 is mounted on the outer surface 44 of the floor 40 beneath the vehicle 10. In one non-limiting example, a support member 48, Fig. 2 provide an additional support function and additional protection for the battery pack 38.

[0029] In a non-limiting example, Fig. As illustrated in Figure 2, the battery pack 38 includes a housing 50 having a base 54 and a plurality of sidewalls 56 connected to and extending from the base 54. A cover 58 is disposed over the plurality of sidewalls 56. The housing 50 contains a number of battery cells (not shown) capable of receiving, storing, and discharging electrical energy. The cover 58 includes an outer surface portion 60 and an inner surface portion 62. Fig. 5. A plurality of openings 64 extend through the cover 58. The openings 64 provide passage for mechanical fasteners 66 to pass through the cover 58 and into the battery pack 38.

[0030] As in Fig. 3, a plurality of mechanical fasteners 66 pass through the floor 40 of the passenger compartment 20 and are connected to the battery pack 38, as explained in more detail below. Each of the plurality of mechanical fasteners 66 passes through the floor 40 into a corresponding one of the plurality of openings 64 in the cover 58 of the battery pack 38. In one non-limiting example, the battery pack 38 includes a connecting member 74 disposed beneath the cover 58. The connecting member 74 includes a surface 77 that includes a plurality of threaded passages 79. Each of the plurality of mechanical fasteners 66 is connected to a corresponding one of the threaded passages 79 to secure the battery pack 38 to the body 12.

[0031] In a Fig. 3 and Fig. 5, a sealing assembly 82 is secured in each of the numerous openings 64 in the cover 58. The sealing assembly 82 has a number of functions. First, the sealing assembly 82 closes the openings 64 so that the battery pack 38 can be subjected to a vacuum test after manufacture to ensure that the housing 50 is properly sealed. The sealing assembly 82 also closes the openings 64 to prevent contamination during transport from a manufacturing facility to an installation facility. The sealing assembly 82 further provides a sealed passage for mechanical fasteners 66. As shown in Fig. 4, the sealing assembly 82 includes a grommet 84, a pressure limiter 86, and a plug 88. The grommet 84 may be formed from a variety of materials, including elastic materials, inelastic materials, a metallic material, and materials of various mixtures or alloys, including metallic alloys.

[0032] Reference is now made to Fig. 5 and Fig. 6, with further reference to Fig.4 in describing the sealing assembly 82. By way of non-limiting example, the grommet 84 includes a first portion 92, a second portion 94, and a connecting portion 96 extending along a sealing axis "S" between the first portion 92 and the second portion 94. The grommet 84 includes a central opening 100 passing through the first portion 92, the second portion 94, and the connecting portion 96. The grommet 84 is inserted into the opening 64. The first portion 92 rests on the outer surface portion 60 of the cover 58 and includes an annular recess 104. The second portion 94 includes a barb portion 106 that engages the inner surface portion 62 of the cover 58. The first portion 92 has a first thickness along the sealing axis "S."

[0033] By way of non-limiting example, the pressure limiter 86 is designed to accommodate compressive loads that may develop during assembly of the battery pack 38 to the body 12 without compromising the effectiveness of the seal. The pressure limiter 86 includes a flange 108 having a second thickness along the seal axis "S" that is less than the first thickness. As explained in more detail herein, the flange 108 fits within the first portion 92 of the grommet 84. The pressure limiter 86 also includes a support portion 110 having a passageway 112. The support portion 110 extends from the flange 108 through the connecting portion 96 of the grommet 84 and, when installed in the opening 64, abuts the surface 77 of the connecting member 74.

[0034] In one non-limiting example, the flange 108 includes an annular recess portion 114 forming an annular step 116. The annular step 116 is received by the annular recess 104 in the first portion 92 of the grommet 84. The first portion 92 of the grommet 84 overlaps the annular step 116. The plug 88 is installed in the passageway 112 of the pressure limiter 86. The plug 88 includes a substantially cylindrical cross-section and is formed from a self-healing material. This means that when punctured, the plug 88 surrounds and seals against the mechanical fastener 66.

[0035] During operation, the sealing assembly 82 can seal the openings 64 and maintain the vacuum within the housing 50. The sealing assembly 82 can also prevent dirt, water, and other contaminants from entering the housing 50 during shipping. When installed, the mechanical fastener 66 is passed through the base 40 and the plug 88 and engages the connecting member 74 through the threaded passages 79. As each mechanical fastener 66 is tightened, the inner surface portion 72 of washer 68 compresses the pressure limiter 86. The support portion 110 of the pressure limiter 86 engages the connecting member 74 and limits the compressive force exerted on the grommet 84. In this way, the grommet 84 continues to seal the opening 64 even when the battery pack 38 is mounted to the body 12.

[0036] The terms "a / an / an" do not imply a quantity limitation, but denote the presence of at least one of the mentioned items. The term "or" means "and / or" unless the context clearly indicates otherwise. References to "an aspect" throughout this specification mean that a particular element (e.g., a feature, structure, step, or property) described in connection with the aspect is included in at least one of the aspects described herein and may or may not be present in other aspects. In addition, it is understood that the described elements in the various aspects may be combined in any suitable manner.

[0037] When an element such as a layer, film, region, or substrate is described as lying "on" another element, it may lie directly on top of the other element, or there may be intervening elements. In contrast, when an element is described as lying "directly on" another element, there are no intervening elements.

[0038] Unless otherwise indicated herein, all examination standards are the most recent standard in effect on the filing date of this application or, if priority is claimed, the filing date of the earliest priority application in which the examination standard appears.

[0039] Unless otherwise defined, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0040] Although the above disclosure has been described with reference to exemplary embodiments, it will be appreciated by those skilled in the art that various changes may be made and equivalent elements may be substituted without departing from the scope of the disclosure. In addition, many changes may be made to adapt a particular situation or material to the teachings of the disclosure without departing from its essential scope. Therefore, the present disclosure is not intended to be limited to the particular embodiments disclosed, but is intended to include all embodiments falling within its scope.

Claims

[1] Battery pack for a vehicle, comprising: a housing comprising a base, a plurality of side walls, and a cover extending over the plurality of side walls, the cover comprising an outer surface portion and an inner surface portion and an opening extending through the outer surface portion and the inner surface portion; a grommet having a central opening disposed in the opening, the grommet having a first portion engaging the outer surface portion, a second portion engaging the inner surface portion, and a connecting portion connecting the first portion and the second portion; a pressure limiter having a passage mounted in the central opening of the spout, the pressure limiter comprising a flange surrounded by the first portion of the spout and a support portion extending through the connecting portion to the second portion of the spout; and a plug arranged in the passage. [2] The battery pack of claim 1, further comprising a connector disposed between the housing and the cover, the connector including a threaded passage aligned with the opening in the cover. [3] Battery pack according to claim 2, wherein the support portion of the pressure limiter abuts the connecting element. [4] The battery pack of claim 1, wherein the first portion of the spout comprises a first thickness and the flange comprises a second thickness different from the first thickness. [5] The battery pack of claim 4, wherein the first thickness is greater than the second thickness. [6] The battery pack of claim 1, wherein the flange of the pressure limiter includes an annular recess, the first portion of the grommet overlapping the annular recess. [7] The battery pack according to claim 1, wherein the grommet is formed of an elastic material. [8] A battery pack according to claim 7, wherein the pressure limiter is formed of an inelastic material. [9] The battery pack of claim 1, wherein the plug is formed of a self-healing, pierceable elastic material. [10] Vehicle comprising: a body defining a passenger compartment having a floor including an inner surface and an outer surface; and a battery pack as described in claim 1 mounted on the outer surface of the floor.

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