Spacer for the top cover of a battery pack, battery pack assembly, and method of attaching a battery pack

Abstract

A spacer for restricting the movement of the top cover of a battery pack toward the vehicle body is disclosed. The spacer includes a rigid support bracket arranged to be attached to the top cover. The elastomeric member supported by the support bracket has first and second portions formed integrally. The first portion is mainly elastically deformed by bending, and the second portion is mainly deformed by compression, and both cooperate to generate a non-linear repulsive force. A method of attaching a battery pack using such a spacer is also disclosed.

Description

Technical Field

[0001] The present disclosure relates to the field of automotive battery packs, and more particularly to spacers used when attaching an automotive battery pack to a vehicle body, assemblies including such spacers, and methods of attaching a battery pack to a vehicle body using such spacers.

Background Art

[0002] The progress of electrification in the automotive industry involves many challenges, such as the design of battery systems and their assembly into electric vehicles such as passenger cars and trucks. Considerations in the design of battery systems include passenger safety such as collision energy absorption, protection of the battery pack against shock and vibration, thermal management, cost and weight constraints, assembly space constraints, and manufacturing and assembly considerations.

[0003] Automotive battery systems (also referred to as battery packs) for electric vehicles can be quite large and heavy. For example, a battery pack mounted on the underside of a passenger car has a size of 2×2 meters and a weight that accounts for about 25% of the total vehicle weight. To design for this large weight and attach it to the vehicle underside, it is necessary to keep the battery pack in a structurally and functionally stable state during driving and to assemble the battery pack efficiently and safely to the vehicle underside. Also, due to the large size of the battery pack, there are issues in terms of allowable error. In the vehicle assembly process, the battery pack is attached to the vehicle underside to form the assembled vehicle body. In many of the latest vehicles, the battery pack includes a structure configured to withstand structural loads and absorb collision energy.

[0004] Generally, an automotive battery pack includes a housing and a number of components disposed within the housing. These components include multiple rechargeable batteries (usually grouped into battery modules), an electronic battery management system, a cooling system, thermal insulation materials, a structure for housing individual battery modules, and so on.

[0005] The housing of an automotive battery pack is generally made of metal such as aluminum and / or steel structures. The housing can include a trough-shaped housing portion and a housing top cover attached to the trough-shaped housing portion to close it. In some designs, the trough-shaped housing portion is provided by a peripheral frame and a bottom cover attached to the peripheral frame. In other designs, the trough-shaped housing portion is provided by an integral component such as a deep-drawn aluminum sheet. The housing can also include an internal compartment or housing structure for housing the battery modules. The top cover of the housing, also known as the top cover or upper shell, is usually manufactured from a metal sheet such as an aluminum sheet. The top cover can have a shape and contour corresponding to the shape and contour of the vehicle body underside. The shape and contour of the vehicle body underside can vary significantly between different automotive brands and models, and accordingly, the top cover of the battery housing is also designed to exhibit a shape and contour corresponding to the shape and contour of the vehicle body underside.

[0006] From an assembly perspective, since there are battery modules within the housing, it is usually not possible to attach the battery pack to the vehicle body underside by attaching the top cover to the vehicle body underside. Therefore, to attach the battery pack to the vehicle body underside, the housing of the battery pack usually has an external attachment function along the side of the housing, for example, elongated aluminum or steel structures attached to both sides of the trough-shaped housing portion, and a plurality of screw holes for receiving assembly screws that are screwed into the vehicle body underside for attaching the battery pack.

[0007] In the prior art, it is known to arrange a plurality of spacer elements made of a foamed elastic material in the space between the lower body of the vehicle and the top cover of the battery pack. The foamed spacer elements are usually rectangular elements and / or more elongated rib-shaped elements that are attached to the upper surface of the top cover by an adhesive. The foamed spacers are slightly compressed when the battery pack is attached with the above-described screws. During driving, the foamed spacers prevent direct contact between the lower surface of the vehicle body and the top cover of the battery pack.

Summary of the Invention

[0008] In view of the above, it is an object of the present invention to provide enhanced spacers and assembly solutions in the field of battery pack assembly for electric vehicles.

[0009] According to one aspect of the present invention concept, there is provided a spacer extending along the axis of the spacer between the upper end and the lower end of the spacer, which is arranged to be provided between the vehicle body and the top cover of the battery pack in order to limit the movement of the top cover towards the vehicle body, and this spacer is a rigid support bracket having a bracket height extending along the axis between the bracket base of the bracket and the bracket top of the bracket, the bracket base being configured to be attached to the top cover and defining the lower end of the spacer, the support bracket and an elastomer member made of a solid elastomer material and supported by the support bracket, having integrally formed first and second portions, the first portion extending to the upper end of the spacer and forming the upper end of the spacer, and the second portion being attached to the support bracket, the elastomer member and the first portion of the elastomer member is configured and arranged to elastically deform mainly by bending of the elastomer material in response to an external force acting on the spacer to generate a first repulsive spring force. The second part of the elastomer member is configured and arranged to elastically deform mainly by compression of the elastomer material when an external force acting on the spacer exceeds a preset value, generating a second repulsive force greater than the first repulsive force generated by the first part. The height of the bracket, plus the height of the elastomer member between the bracket top and the upper end of the spacer, forms the total height of the spacer.

[0010] From a general functional perspective, the spacer according to the present invention, during driving, · A limiter and a buffer for the movement of the top cover in the vertical direction · An absorber of vibrations and noises between the battery pack and the vehicle body · A heat filter between the lower surface of the vehicle body and the battery pack functions as.

[0011] During driving, the elastomer member of the spacer according to the present invention undergoes elastic deformation in response to an external force caused by the movement of the top cover relative to the lower surface of the vehicle body. As described above, such movement of the top cover towards the lower surface of the vehicle body may be due to heat generated in the battery pack. This heat can cause the pressure inside the battery pack to change and the top cover to be directly heated. Both phenomena can cause the top cover to expand or deform, and without countermeasures, unacceptable direct contact between the top cover and the lower surface of the vehicle body may occur. In some cases, due to a specific movement of the entire battery pack, the top cover may move vertically.

[0012] Due to the elastic deformation of the elastomer member, a repulsive spring force is generated that acts to oppose and limit the upward movement of such a top cover. For the initial slight movement of the top cover, the repulsive spring force is mainly generated by the first part of the elastomer member that deforms mainly by bending. The bending of the first part of the elastomer member in response to an external force occurs due to its elastic bending and can move downward into the space of the spacer. The value of the first repulsive force generated by the first part of the elastomer member can increase in response to an increase in the movement of the cover lid and the accompanying increase in the bending of the first part.

[0013] When the external force acting on the spacer exceeds a preset value and accordingly the total height of the spacer decreases to a certain extent, the second part of the elastomer member becomes active and helps to limit further movement of the top cover. As the top cover moves further upward, the second part of the elastomer member is elastically compressed along the axis of the spacer, generating a second repulsive spring force higher than the first repulsive spring force generated by the first part. The result can be expressed as the overall non-linear repulsive spring force characteristic of the spacer. When the second part becomes active, a distinct increase in the repulsive spring force can be achieved. As a non-limiting example, in the operating range of the first part of the elastomer member, the initial first repulsive force can be selected so that the total reaction force of all the spacers of the battery pack does not exceed 100 N, while after the second part of the spacer becomes active (i.e., after the movement of the top cover exceeds a threshold corresponding to the normal operating range of the spacer, such as 7 mm), the second higher repulsive force generated by the second part of the spacer can be selected so that the total reaction force of all the spacers of the battery pack is at least 300 N.

[0014] A general advantage of the present invention concept is that the present invention provides improved controllability and new functions compared to the prior art foaming elements.

[0015] The present invention concept provides advantages over the prior art upper foam spacers with respect to the control of the repulsive spring force or reaction force generated by the spacer on the top cover of the battery pack. These advantages apply to both assembly conditions and driving conditions. The prior art foam spacers do not provide any control function. They are merely foam elements.

[0016] The present invention improves the possibilities of control and design with respect to the dependency between the degree of compression of the spacer and the repulsive spring force generated in response to the compression of the spacer.

[0017] According to the present invention, it becomes possible to design the spacer so as to provide optimal repulsive spring characteristics according to the available space / height of the spacer between the vehicle body and the battery pack.

[0018] Also, the spacer according to the present invention concept can be designed to handle the loads generated during driving over a considerably long movement distance of the spacer, i.e., over a large operating range of the elastomeric member of the spacer.

[0019] The ability to more appropriately control the repulsive spring force of the spacer attached between the top cover of the battery pack and the lower surface of the vehicle body is advantageous for several reasons.

[0020] · During the manufacturing and assembly stages, when attaching the battery pack close to the vehicle body bottom surface, the spacers arranged on the top cover can contact the vehicle body bottom surface to prevent direct contact between the top cover and the vehicle body. During the installation work, when the battery pack is firmly fixed to the vehicle body with screws along the side surface of the battery pack, a plurality of spacers arranged on the top cover are slightly compressed (pre-loaded) according to the attachment of the battery pack. In this assembly procedure, if the initial repulsive spring force generated by each individual spacer is too large, the pre-loaded total repulsive force generated by all the spacers will make it difficult to position and attach the battery pack. From the perspective of this assembly, the initial repulsive spring force of the non-compressed spacer should not be too high.

[0021] · On the other hand, from the perspective of the driving state, the repulsive force generated by the spacer at the pre-loaded position during use must be sufficient to prevent the top cover from moving excessively towards the vehicle body bottom surface. Such movement of the top cover towards the vehicle body may be caused by the heat generated in the battery pack. The heat can change the pressure inside the battery pack, and the top cover may also be directly heated, both of which may cause undesirable expansion or shape change of the top cover. If this is not restricted, the top cover and the vehicle body may come into direct contact. The degree of movement of the top cover can vary significantly depending on the design of the vehicle or the battery. As a non-limiting example, it may be about 5 - 10 mm. For various reasons, it is important to prevent and limit such up and down movement of the top cover. From this perspective, it is advantageous that the value of the repulsive spring force generated by the spacer during such movement of the top cover can be controlled, and also how the repulsive spring force depends on the compression degree of the spacer, that is, the distance - force characteristics can be controlled. In particular, it is advantageous to design the spacer such that the repulsive force has a non-linear characteristic, showing a low initial repulsive spring force for a relatively small movement of the top cover and a very high repulsive spring force for a larger movement of the top cover close to the maximum allowable movement of the top cover.

[0022] According to the present invention, it becomes possible to highly control both the general value of the repulsive spring force for specific needs of the battery pack assembly and the dependency between the degree of compression of the spacer and the repulsive spring force generated in response to the spacer compression. In the prior art simple foam spacers used for mounting automotive battery packs, the repulsive spring force generated by the foam material is essentially proportional to the compression distance of the foam material and can only be controlled by changing the thickness of the foam material. According to the inventive concept of using an elastomeric element made of a solid elastomer material and supported by a rigid support bracket, it becomes possible to design the spacer to exhibit particularly controlled non-linear force-distance characteristics so as to generate an optimal repulsive force for various degrees of compression of the spacer.

[0023] A further advantage of the inventive concept is obtained from the arrangement of the rigid support bracket that supports the elastomeric element and forms part of the total height of the spacer. The rigid support bracket can be manufactured in whole or in part from a rigid plastic material such as, for example, a reinforced plastic material. The elastomeric member may be molded onto the support bracket or assembled to the support bracket by adhesion and / or mechanical connection.

[0024] In a given assembly, the support bracket can have a fixed (unchanging) bracket height, while the elastomeric member of the spacer is flexible and can change height in response to the movement of the top cover. The combination of the unchanging bracket height and the variable height of the portion of the elastomeric element that extends beyond (above) the bracket top defines the total variable height of the spacer corresponding to the variable distance between the top cover of the battery pack and the lower surface of the vehicle body. By using the rigid support bracket as part of the total height of the spacer, many advantages are obtained.

[0025] · One of the advantages of using the rigid support bracket as part of the total height of the spacer is related to safety. The rigid support bracket defines the potential absolute minimum distance between the top cover and the lower surface of the vehicle body. If for some reason the upward movement of the top cover becomes excessive and the repulsive force generated by the elastomeric member of the spacer cannot accommodate any further movement, the rigid support bracket functions as a rigid spacer, effectively preventing unacceptable direct contact between the top cover of the battery and the lower surface of the vehicle body. From this perspective, the minimum bracket height is, as a non-limiting example, only about 10 mm. Depending on the design of the spacer according to the present invention, such a potential absolute minimum distance between the top cover and the lower surface of the vehicle body may be equal to the bracket height or equal to the bracket height plus the compressed portion of the elastomeric member located above the upper surface of the support bracket.

[0026] · Another advantage of using the rigid support bracket as part of the total height of the spacer is related to the option of being able to change the bracket height. The distance between the top cover of the battery pack and the lower surface of the vehicle body can vary significantly between different vehicle models, different battery packs, and different positions on a given top cover. Such variations in the space where the spacer is placed can be at least partially addressed by changing the bracket height without necessarily changing the design or height of the elastomeric member. This is a general advantage from a manufacturing perspective. Also, it is possible to maintain the same repulsive spring force characteristics of the set of spacers while only changing the bracket height. This can be advantageous when it is necessary to make the repulsive spring force characteristics the same for all spacers attached to a given top cover with different distances to the lower surface of the vehicle body.

[0027] ·Another advantage of using the rigid support bracket as part of the total spacer height is related to creating an optimal operating range for the elastomeric member. By using the rigid support bracket as part of the total spacer height, there is an advantage that the bracket height can be changed and selected in the design process to obtain a desired operating range for the flexible elastomeric member. For example, it is advantageous if the spacer can absorb a relatively large tolerance in the distance between the vehicle body and the top cover. Such a tolerance can be on the order of plus or minus a few millimeters. This can be solved by selecting a bracket height that gives a sufficiently large operating range for the elastomeric member. As a non-limiting example, if the total distance between the top cover and the vehicle body is about 19 mm (tolerance of 15.5 ± 3.5 mm) at a particular position of the top cover and the desired flexible operating range (movement of the top cover) is about 7 ± 3.5 mm, a bracket height of about 10.5 mm can be selected.

[0028] ·A further advantage of using the rigid support bracket as part of the spacer is related to the operation of the elastomeric member and the designability of various repulsive spring force characteristics thereof. The support bracket has a specific bracket height. At least the upper part of this height can be used to accommodate the flexible movement / compression of the elastomeric member. In a preferred embodiment, the support bracket has an internal bracket cavity arranged to receive at least a portion of the elastomeric member. The size of this portion may increase as the elastomeric member deforms. In some embodiments, the elastomeric member can also be completely accommodated within the bracket cavity for a sufficiently large external force.

[0029] Further advantages of the inventive concept result from using solid elastomer materials as compared to prior art foam materials. When using foam materials, it is not possible to control the distance-force characteristics, and the values of the spring forces also differ significantly. A spacer made of a foam material, as a function of the foam material, merely creates a reaction force due to its linear force-distance characteristic. As described above, according to the present invention, it becomes possible to control the repulsive spring force or the reaction force at various points of the movement curve. Another advantage of the present invention is that in the prior art, more foam material is required to generate the same reaction force, which is not always possible in the limited available space between the battery pack and the vehicle body underside.

[0030] In some embodiments, a rigid support bracket is configured and arranged such that, in response to an increase in the deformation of the elastomer member caused by an external force acting on the spacer, an increased portion of the elastomer member is received within the internal space of the support bracket. In such embodiments, the elastomer member may already be partially received within the bracket cavity in the initial non-compressed state of the spacer. In some embodiments, the entire second portion may be disposed within the bracket cavity. As the elastomer member deforms due to an external force, a larger portion or volume of the elastomer member, particularly the first portion of the elastomer member, may be received within the bracket cavity.

[0031] In some embodiments hereinafter referred to as "dome design", the first portion of the elastomeric member includes a dome-shaped wall having a convex outer surface facing away from the support bracket, and the apex of the dome-shaped wall defines the upper end of the spacer in its uncompressed state. The dome-shaped wall can define an internal space within the dome. During operation, the dome-shaped wall is configured to elastically deform from an initial curved shape to a less curved shape mainly by bending in response to an external force acting on the spacer, thereby reducing the height of the first portion of the elastomeric member. During this bending deformation, the wall of the dome bends into the initial internal space of the dome. In some embodiments, the dome-shaped wall can have a circular or non-circular bottom. In some embodiments, the dome-shaped wall can also exhibit a non-uniform curvature between its apex and bottom. For example, the dome shape can have two different curvatures such that the curvature is greater closer to the apex and smaller closer to the bottom of the dome. This can be advantageous when the dome-shaped design may result in an initial response that is too weak.

[0032] In embodiments related to the dome design, the support bracket can include an upwardly open bracket cavity arranged to receive the increased portion when the dome-shaped wall deforms. This has the advantage of providing a space under the "dome" for receiving the elastomeric material when the dome-shaped wall is flattened. In some embodiments, substantially the entire first portion may be received within the bracket cavity in response to a sufficiently high external force. Also, in some embodiments, the bottom of the dome-shaped wall may already be disposed within the bracket cavity and attached to the support bracket therein in a state where the spacer is not compressed. In other embodiments, the dome-shaped wall can also be attached to the support bracket only through the second portion of the elastomeric member.

[0033] In an embodiment according to the dome design, the second part of the elastomeric member can be arranged around or circumferentially of the dome-shaped wall. The second part may be arranged above the upper surface of the upper end of the support bracket. In the initial assembled state, the second part of the elastomeric member may be arranged along the axis of the spacer at a position such that there is a distance between the upper end of the second part and the lower surface of the vehicle body. In such an embodiment, since the second part of the elastomeric member is spaced from the lower surface of the vehicle body, it is initially inactive. When a sufficiently large force is applied, the first part becomes unable to cope with the movement of the top cover, and the lower surface of the vehicle body finally contacts the second part of the elastomeric member, whereby the second part becomes active. As a result, when the top cover moves further upward, the second part is compressed in the vertical direction, and a second reaction spring force greater than the reaction spring force generated by the dome-shaped wall is generated. In a preferred embodiment, the second part is at least partially located above the upper surface of the support bracket. Thereby, the rigid support bracket functions as an efficient rigid support in a state where the second part is compressed, and as a result, when the second part becomes active, a higher reaction spring force than intended is obtained. It will be understood that the total reaction spring force of the spacer is the sum of the reaction spring forces generated by the first and second parts of the elastomeric member.

[0034] In an embodiment according to the dome design, the second portion of the elastomeric member can include a plurality of elastomeric studs, each stud protruding beyond the stud height towards a stud end of the stud that faces away from the support bracket. The stud height is selected such that the stud end is initially spaced from the lower surface of the vehicle body in the initial assembled state. As described above, when the movement of the top cover is sufficiently large, the studs become active and, by their compression, the total rebound spring force of the spacers clearly increases. One advantage of using a plurality of studs or "towers" is that the material that undergoes compression can deform in the space between the studs. Another advantage of using studs to generate a second rebound spring force is that such studs can include studs of different stud heights. In such an embodiment, the taller studs become active first, and then the shorter studs become active. This allows for the design of a smoother or less abrupt spring force characteristic, yet still allows for a significant increase in the rebound spring force compared to the force generated in the first portion.

[0035] In some embodiments hereinafter referred to as "pillar design", the support bracket includes a peripheral bracket wall extending from a bracket base to a bracket top and defining an internal bracket cavity that opens towards the upper end of the support bracket, and a second portion of the elastomeric member is at least partially located within the bracket cavity and attached to the bracket wall within the bracket cavity. In this design, the first portion of the elastomeric member may be configured and arranged to elastically deform by bending itself upwards in response to an external force acting on the spacer. Similar to the dome design, such bending may occur by the first portion moving downwards during deformation within an initially open space defined by the elastomeric member. However, in the pillar design, the first portion of the elastomeric member may be configured and arranged to undergo bending by increasing the curvature at least in part. The first portion of the elastomeric member is configured and arranged to be fully accommodated within the bracket cavity in response to an external force of sufficient magnitude acting on the spacer, such that ultimately the upper surface of the bracket wall contacts the lower surface of the vehicle body. In the pillar design, the first portion of the elastomeric member can have a lateral extent with respect to the axis of the spacer that is smaller than the lateral extent of the bracket top. The pillar design may be advantageous to use when the space available for the spacer is limited.

[0036] According to a further aspect of the inventive concept, there is provided a top cover arranged to be attached to a housing of an automotive battery pack, the top cover comprising a plurality of spacers according to the present invention, and each bracket base of each spacer within the plurality of spacers being attached to the upper surface of the top cover, whereby the spacers project from the upper surface of the top cover along the full height of the spacers. In some embodiments, the plurality of spacers comprises spacers having different bracket heights from each other and optionally the same elastomeric member as each other.

[0037] According to a further aspect of the inventive concept, a battery pack having the top cover described above is provided.

[0038] According to a further aspect of the inventive concept, an assembly is provided, the assembly comprising a vehicle body, and a battery pack having the top cover described above, the battery pack being attached to the lower surface of the vehicle body, wherein a distance between an upper surface of the top cover and a lower surface of the vehicle body is such that a plurality of spacers provided on the top cover are in a biased state when the battery pack is attached to the lower surface of the vehicle body.

[0039] According to a further aspect of the inventive concept, a method for attaching an automotive battery pack is provided, the method comprising attaching a plurality of spacers according to the present invention to an upper surface of a top cover of an automotive battery pack, and attaching the battery pack provided with the spacers to a lower surface of the vehicle body, wherein, in response to the attachment of the battery pack, a first portion of an elastomeric member of the plurality of spacers undergoes an initial deformation to form an initial biasing state of the spacers.

[0040] Terminology In the present disclosure, the term "solid elastomeric material" should be construed as a non-foamed elastomeric material such as solid silicone rubber, for example. However, the elastomeric member itself made of such a material may optionally have openings.

[0041] In the present disclosure, the term "bending" should be construed as a change in shape to a more curved shape and / or a less curved shape. Such bending of a component made of an elastomeric material may involve some compression, but in the present disclosure, "bending" is used to distinguish a deformation caused by compression only.

[0042] In the present disclosure, the term "dome-shaped" should be construed as a shape curved in two directions. Optionally, the dome-shaped surface is the surface of a solid of revolution generated by rotating a meridian curve about an axis of rotation. From the bottom of the dome to the apex of the dome, the curvature or radius may vary or may be constant. The bottom of the dome can have various geometric shapes, such as circular or non-circular.

Brief Description of the Drawings

[0043] Hereinafter, with reference to the drawings, the present inventive concept, some non-limiting embodiments, and further advantages of the present inventive concept will be described.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0044] First, with reference to FIGS. 5 to 7, the general usage position of the spacer according to the present invention will be described. As shown in FIGS. 5 to 7, a plurality of spacers 10 according to an embodiment of the present invention are configured and arranged to be attached to the top cover 110 of the automotive battery pack 100 of a vehicle 200 such as an electric drive passenger vehicle. In the assembly process, before attaching the top cover 110, as shown in FIG. 7, the spacers 10 can be first attached to the upper surface of the top cover 110 in a number and pattern suitable for a specific vehicle type and battery design. Then, the top cover 110 can be attached to the trough-shaped housing 120 of the battery pack 100 as shown in FIGS. 5 and 6. Finally, as shown in FIG. 5, the battery pack 100 can be attached to the lower surface 210 of the vehicle body. Optionally, after attaching the top cover 110 to the battery housing 120, the spacers 10 can also be attached to the top cover.

[0045] Also, as an option in the manufacturing process, the spacer 10 can also be used as a spacer between the stacked top covers 110. At a first location, the spacer 10 can be attached to the top cover 110. Then, a plurality of top covers 110 each provided with the spacer 10 are stacked on top of each other on a pallet and transported to another location, where the top cover 110 can be attached to the battery housing 120. During transportation, the spacer 10 functions as a protective cushioning material and a distance limiting material between the stacked top covers 110.

[0046] As described above, inside the housing 120 of the battery pack 100, a number of components (not shown), such as a plurality of rechargeable batteries (usually grouped into battery modules), an electronic battery management system, a cooling system, heat insulation material, and a structure for accommodating individual battery modules, can be arranged. The housing 120 can be provided with an external electrical connection portion 130. In some designs, the trough-shaped housing 120 is provided by a peripheral frame and a bottom cover attached to the peripheral frame. In other designs, the trough-shaped housing 120 is provided by an integral component such as a deep-drawn aluminum sheet. The housing 120 can also be provided with an internal compartment or accommodation structure for accommodating the battery modules.

[0047] The top cover 110 (FIG. 7) is typically manufactured from a metal sheet such as an aluminum sheet. The top cover 110 can have a shape and contour corresponding to the shape and contour of the vehicle body lower surface 210, as schematically shown in FIG. 5. The shape and contour of the vehicle body lower surface 210 can vary significantly between different vehicle models and different battery packs 100. For this reason, the top cover 110 of the battery pack 100 can be designed to show a shape and contour corresponding to the shape and contour of the vehicle body lower surface 210. As shown in the figure, by way of non-limiting example, the contour of the top cover 110 can be provided with a raised portion, such as a rectangular raised portion 111, corresponding to a similar contour of the vehicle body lower surface 210. However, due to the design of the spacer 10 according to the present invention, it is also possible for the top cover 110 to show a shape and contour that does not correspond well to the shape and contour of the vehicle body lower surface 210.

[0048] In the assembly process, the top cover 110 is attached to the housing 120 by screws passing through screw holes 140 arranged on the periphery of the top cover 110. Usually, the top cover 110 is hermetically sealed with respect to the housing 120. Also, in order to cope with thermal events of the battery pack 100, it is necessary to properly seal the top cover 110 to the housing 120 to prevent heat and smoke from entering the compartment.

[0049] In the assembly process, a plurality of spacers 10 according to the present invention are provided on the battery pack 100, and are preferably pre-attached to the top cover 110. As described above, since there is a battery module in the housing 120, usually, the battery pack 100 cannot be attached to the vehicle body lower surface 210 by directly attaching the top cover 110 to the vehicle body lower surface 210. Therefore, in order to attach the battery pack 100 to the vehicle body lower surface 210, the housing 120 of the battery pack is usually provided with an external attachment function 150 along the side surface of the housing 120, for example, elongated aluminum or steel structures arranged on both sides of the trough-shaped housing 120, and a plurality of screw holes (not shown) for receiving the assembly screws screwed into the vehicle body lower surface 210 for attaching the battery pack 100 are provided.

[0050] As will be described in more detail below, the spacer 10 is not essential, but preferably is designed to have a height such that when the battery pack 100 is attached to the vehicle body lower surface 210 during the assembly process, the first portion of the elastomeric member of the spacer 10 undergoes a specific deformation, thereby creating an initial preloaded state of the spacer 10 during battery pack attachment. One of the functions of the spacer 10 during driving is to limit and prevent the top cover 110 from moving excessively towards the vehicle body lower surface 210.

[0051] First Embodiment Referring to FIGS. 1A to 1E, the spacer 10 according to the first embodiment of the present invention will be described, and referring to FIGS. 2A to 2E, its operation will be described.

[0052] The spacer 10 of the first embodiment extends along the axis A between the upper end 11 of the spacer 10 and the lower end 12 of the spacer 10 (FIG. 1C). The axis A is usually vertical at the use position of the spacer 10, but an inclined arrangement is also possible.

[0053] The spacer 10 includes an elastomeric member 20 and a rigid support bracket 40 arranged to support the elastomeric member 20. The elastomeric member 20 of the spacer 10 according to the present invention can be attached to the support bracket 40 by molding or assembly with an adhesive or the like. The support bracket 40 can be manufactured from any suitable rigid material such as a suitable plastic material and can be reinforced as required. As shown in FIG. 1C, the support bracket 40 has a bracket height B along axis A between a bracket base 42 and a bracket top 41. For a given spacer 10, the bracket height B is fixed, but as will be described later, one of the advantages of the present inventive concept is that the bracket height B can be changed. Optionally, a support bracket 40 having an adjustable bracket height B is also possible.

[0054] In the illustrated embodiment, the support bracket 40 includes a cylindrical bracket wall 43 that extends between the bracket top 41 and the bracket base 42 and defines an internal bracket cavity 44. In the illustrated embodiment, the bracket base 42 is integrally formed with the bracket wall 43 and includes a plate-like member that partially extends outside the periphery of the bracket wall 43. A double-sided adhesive tape may be provided on the lower surface of the bracket base 42 to attach the battery pack 100 to the top cover 110. In the illustrated embodiment, the shape of the bracket wall 43 is cylindrical. Other shapes, such as non-circular, rectangular, conical, etc. are also possible. As a main condition of the support bracket 40, the support bracket 40 needs to be arranged to firmly support the elastomeric member 20 of the spacer 10 on the top cover 110 and enable deformation of the elastomeric member 20 in response to an external force caused by the movement of the top cover 110. In some embodiments, in response to deformation of the elastomeric member 20, the support bracket 40 can also be configured to accommodate a variable portion or volume of the elastomeric member 20 within the internal bracket cavity 44. In an alternative embodiment, the support bracket 40 may have an internal structure that is at least partially solid.

[0055] By way of illustration and not limitation, the support bracket 40 can have a bracket height B corresponding to about 50% of the total height T (FIG. 1C) of the spacer 10 in its initial undeformed state, for example about 65 mm. The diameter of the bracket wall 43 can be, by way of non-limiting example, about 30 mm. From the perspective of manufacturing cost, it is desirable to limit the amount of elastomeric material used for the elastomeric member 20, and correspondingly, it may be desirable to design the support bracket 40 such that the bracket height B occupies most of the total spacer height T. On the other hand, in order to ensure the required operating range for the elastomeric member 20, it is necessary to prevent the bracket height B from becoming too large. In this numerical example, in the state where no load is applied to the spacer 10 shown in FIG. 1C, the elastomeric member 20 can extend about 10 mm above the bracket top 41, and as a result, the total spacer height T is 65 mm in the state where no load is applied to the spacer 10.

[0056] The elastomeric member 20 of the spacer 10 according to the present invention is made of a non-foamed elastomeric material called "solid elastomeric material" in the present disclosure. The elastomeric material can exhibit an appropriate hardness (soft, medium, hard). The durometer, expressed as a numerical value on the Shore A scale, can be, by way of non-limiting example, within the range of 40 to 70 (Shore A).

[0057] According to the inventive concept, the elastomeric member 20 of the spacer 10 includes at least a first portion and a second portion, the first portion becoming active first to generate a first repulsive spring force, and the second portion becoming active thereafter to generate a second, higher repulsive spring force. In the first embodiment shown in FIGS. 1A - 1E, the first portion of the elastomeric member 20 is constituted by a domed wall 21 having an outer surface convex in a direction away from the support bracket 40. This domed wall 21 defines an internal space, and in response to an external force, the domed wall 21 can deform into this internal space. The apex 22 of the domed wall 21 defines the upper end 11 of the spacer 10 in the state where no load is applied in FIGS. 1A - 1C. The bottom 23 of the domed wall 21 is below the bracket top 41 and is located inside the bracket cavity 44. The domed wall 21 can have a constant curvature or a varying curvature between its bottom 23 and apex 22. As described above, in order to avoid the initial reaction force becoming too weak, it may be desirable to increase the curvature near the apex 22. The second portion 24 of the elastomeric member 20 is circumferentially disposed around the domed wall 21 and is located above the bracket top 20 such that at least a portion thereof is vertically supported from below by the rigid bracket wall 43. In the illustrated embodiment, the second portion 23 includes a lower ring-shaped portion attached to the bracket top 41, and a plurality of vertically projecting portions 25a - 25c are circumferentially spaced apart from each other around the first domed portion 21. In this embodiment, the plurality of projecting portions or studs 25a - 25c have different vertical heights (H2 - H4) from each other, all have upward-facing stud upper ends, and those stud upper ends are vertically spaced apart from the apex 22 in the state where no load is applied to the spacer 10, and are also vertically spaced apart from the vehicle body lower surface 210 in the initial assembled state of the spacer (FIG. 2A).

[0058] In the illustrated embodiment, the vertically projecting portions are · a first stud 25a (FIG. 2C) whose upper end is located at a height H2 above the bracket top 41 of the support bracket 40, and · A second stud 25b (FIG. 2D) whose upper end is located at a slightly lower height H3 < H2 above the bracket top 41 of the support bracket 40, · And a third stud 25c (FIG. 2E) whose each end is located at an even lower height H4 < H3 above the bracket top 41 of the support bracket 40.

[0059] The studs 25a - 25c are configured and arranged to deform mainly by vertical compression of the solid elastomer material and generate a second repulsive spring force when activated in response to a greater movement of the top cover 110 of the battery pack 110. The rigid support bracket 40 functions as a rigid vertical support below the studs 25a - 25c during this compression. The spacing 26 between adjacent studs 25a - 25c allows the elastomer material to expand laterally within the spacing 26 during compression. In the illustrated embodiment, the lowest stud 25c is formed as a rib 25a, each having an elongated spread in the circumferential direction. In an alternative embodiment, the studs 25a - 25c can be omitted and replaced with a continuous ring - shaped wall forming the upper end of the second portion of the elastomer member 20. In other alternative embodiments, the heights of all the studs can be made the same. The advantage of providing studs of different heights is that it produces a more gradual increase in force when the second portion of the elastomer member 20 becomes active. It will be understood that each additional set of studs becoming active exhibits a definite (non - linear) increase in the second repulsive force.

[0060] Here, the operation of the spacer 10 of the first embodiment shown in FIGS. 1A - 1E will be described with reference to FIGS. 2A - 2E.

[0061] FIG. 2A shows the spacer 10 of the first embodiment in an unloaded state spaced from the vehicle body underside 210. The total height T of the spacer 10 is T = B + H0, where H0 is the height of the portion of the elastomer member 20 extending beyond the bracket top 41 in the unloaded state of the spacer 10.

[0062] Figure 2B shows the spacer 10 in the initial assembled state. The battery pack 100 is attached to the lower surface 210 of the vehicle body. Correspondingly, the spacer 10 attached to the top cover 110 is slightly compressed by the flattening of the dome-shaped wall 21. The dome-shaped wall 21 has a portion protruding beyond the bracket top 41, and its height is H1 < H0. In this initial assembled state, the stud ends of all the studs 25a to 25c are separated from the lower surface 210 of the vehicle body.

[0063] Figure 2C shows the spacer 10 in a state where the first part of the elastomeric member 20 has reached its normal operating range. Contact occurs between the highest stud 25a and the lower surface of the vehicle body, and the protruding height of the elastomeric member 20 above the bracket top 41 is H2 < H1. The elastic response by the stud 25a is substantially stiffer than the response from the dome-shaped wall 21, achieving a significant increase (non-linear) in the repulsive spring force, which can thereby efficiently counteract further movement of the top cover 110.

[0064] Figure 2D shows the spacer 10 in a state where the top cover 110 moves further towards the lower surface 210 of the vehicle body, thereby also contacting the next highest stud 25b here, and a further non-linear increase in the repulsive spring force has occurred. The protruding portion of the elastomer has decreased to a height H3 < H4 here.

[0065] Figure 2D shows the spacer 10 in a state where it has also contacted the lowest stud 25c, resulting in an even greater repulsive spring force.

[0066] Second Embodiment Next, with reference to FIGS. 3A to 3C, the spacer 10 of the second embodiment according to the present invention will be described, and its operation will be described with reference to FIGS. 4A and 4B. The same reference numerals as those in the first embodiment are assigned to the similar parts. The description in the first embodiment regarding the material of the spacer, optional features and its use, operation and basic functions is also applicable to the second embodiment when applicable.

[0067] According to the second embodiment, the first portions 50 to 52 of the elastomer member 20 are located above the second portion 53 of the elastomer member 20 and are integrally formed with this second portion. The elastomer member 20 includes a first upper portion 50 to 52 configured and arranged to operate mainly by bending, and a second lower portion 53 below the upper portion, configured and arranged to operate mainly by compression.

[0068] In the illustrated second embodiment, the second portion of the elastomer member 20 does not have a free upper surface with an initial interval from the vehicle body lower surface 210 corresponding to the stud free ends of the studs 25a to 25c. Instead, as a result of the first portions 50 to 52 of the elastomer member 20 being initially deformed to such an extent that they deform the second portion 53 downward and start compressing it, the second portion 53 becomes active.

[0069] The embodiment of FIGS. 3A to 3C shows an example of the spacer 10 in which the bracket height B occupies a further larger proportion of the total height T of the spacer.

[0070] As described above, the elastomer member 20 of the spacer according to the present invention can be connected to the support bracket 40 by molding or by subsequent assembly and attachment. The embodiments of FIGS. 3A to 3C show a second alternative. As shown in FIG. 3C, the lower portion of the elastomer member 20 includes a circumferential mounting groove 55 defined by an upper portion 53a and a lower portion 54. The support bracket 40 is provided with an internal mounting flange 45 having a through opening 46 for receiving the lower portion 54 of the elastomer member 20. During assembly, due to the deformation of the lower portion 54, the mounting groove 55 engages with the mounting flange 45. This mounting principle can optionally also be used in the first embodiment. If it is desirable for the elastomer member 20 to be completely housed within the support bracket 40, it is preferably mounted inside the support bracket 40.

[0071] Optionally, as shown in FIG. 4b, the dimensions of the elastomer member 20 relative to the dimensions of the bracket wall 43 may be such that when a sufficiently large external force is applied, the elastomer member 20 is completely housed within the bracket cavity 44. Thereby, when a sufficiently large external force is applied, the upper surface 41 of the bracket wall 43 comes into direct contact with the vehicle body lower surface 210, and the bracket height B defines the minimum spacer height T.

[0072] Next, the operation of the second embodiment of FIGS. 3A to 3C will be described with reference to FIGS. 4A and 4B. FIG. 4A shows the spacer 10 with the bracket base 42 attached to the top cover 110 before the battery pack 100 is attached to the vehicle body lower surface 210. FIG. 4B shows the spacer 20 in a deformed state in which the first portions 50 to 52 of the elastomer member 20 are bent to be essentially completely deformed to the extent that compression of the second portion 53 is initiated. Here too, there is still a distance between the bracket top 41 and the vehicle body lower surface 210. When the top cover 110 moves further upward, the elastomer member 20 is finally compressed to the extent that it is completely housed within the bracket cavity 44, where the bracket top 41 provides a final rigid movement stopper.

[0073] As described above, the first portion of the elastomeric member 20 is configured and arranged to operate mainly by bending. To obtain such an operation, the first portion in the illustrated embodiment includes a funnel-shaped upper portion 50, an intermediate portion 51 that is curved inward with a thin wall thickness, and a lower portion 52. The deformation of the first portion of the elastomeric member 20 is shown in the enlarged view of FIG. 4B, which shows how the first portion is bent onto itself. In this embodiment, there is free space outside the periphery of the intermediate portion 51, enabling bending. Also, as shown in FIG. 3C, the lower portion 52 has a slightly thinner wall thickness compared to the second portion 53, which also serves to facilitate the bending operation.

[0074] Referring to FIGS. 6 and 7, the illustrated example of the battery pack 100 includes a cover lid 110 having a raised portion or step portion 111 at one end. The spacer attached to the raised portion is labeled 10b. This drawing is for showing options having various bracket heights B for a given top cover 110. As shown in the enlarged view of FIG. 6, the spacer 10b on the raised portion 111 has a lower bracket height B compared to the remaining spacers 10a. However, as shown in FIG. 6, the elastomeric member 20 is the same between the spacers 10a, 10b and can provide the same repulsive spring force characteristics to all the spacers on the top cover 110.

Claims

1. A spacer, which extends along the axis of the spacer between the upper end and the lower end of the spacer and is configured to be provided between the vehicle body and the top cover of the battery pack in order to restrict the movement of the top cover toward the vehicle body, A rigid support bracket having a bracket height extending along the axis between the bracket base and the bracket top of the bracket, wherein the bracket base is configured to be attached to the top cover and defines the lower end of the spacer, The elastomer member is supported by the support bracket and is made of a solid elastomer material, having a first and second integrally formed portion, the first portion extending to the upper end of the spacer and forming the upper end of the spacer, and the second portion being attached to the support bracket. The first portion of the elastomer member is configured and positioned to generate a first rebound spring force by elastically deforming, mainly by bending the elastomer material, in response to an external force acting on the spacer. The second portion of the elastomer member is configured and arranged to elastically deform, mainly by compression of the elastomer material, when the external force acting on the spacer exceeds a preset value, thereby generating a second repulsive force that is greater than the first repulsive force generated by the first portion. A spacer characterized in that the total height of the spacer is formed by adding the height of the bracket to the height of the elastomer member between the top of the bracket and the upper end of the spacer.

2. In the spacer according to claim 1, A spacer characterized in that, when the deformation of the elastomer member increases due to the external force acting on the spacer, the support bracket is configured and positioned such that the increased portion of the elastomer member is accommodated within the internal space of the support bracket.

3. In the spacer according to claim 2, The spacer is characterized in that, when the deformation of the elastomer member increases due to the external force acting on the spacer, the support bracket is configured to accommodate the increased portion of the first part of the elastomer member within the internal space of the support bracket.

4. In the spacer according to any one of claims 1 to 3, A spacer characterized in that the first portion of the elastomer member includes a dome-shaped wall having a convex outer surface facing away from the support bracket, and the apex of the dome-shaped wall defines the upper end of the spacer when no load is applied to the spacer.

5. In the spacer according to claim 4, The spacer is characterized in that the dome-shaped wall has a bottom that is at least partially located within the internal cavity of the support bracket.

6. In the spacer according to claim 4, The second portion of the elastomer member is Arranged circumferentially around the dome-shaped wall, It is located at least partially above the upper end of the support bracket, and A spacer characterized in that, when no load is applied to the spacer, it is located at a position away from the upper end of the spacer.

7. In the spacer according to claim 6, The spacer is characterized in that the second portion of the elastomer member includes a plurality of elastomer studs arranged circumferentially around the dome-shaped wall, and each stud of the elastomer studs protrudes in the axial direction toward the stud end of the stud that faces away from the support bracket.

8. In the spacer according to claim 7, A spacer characterized in that the plurality of elastomer studs include several elastomer studs having different stud heights from the other elastomer studs.

9. In the spacer according to claim 4, The spacer is characterized in that the support bracket includes a bracket wall extending circumferentially around the axis, and the diameter of the bracket is larger than the diameter of the bottom of the dome-shaped wall.

10. In the spacer according to any one of claims 1 to 3, The spacer is characterized in that the support bracket includes a peripheral bracket wall that extends from the bracket base to the bracket top and defines an internal bracket cavity that opens toward the upper end of the support bracket, and a second portion of the elastomer member is at least partially located within the bracket cavity and attached to the bracket wall within the bracket cavity.

11. In the spacer according to claim 10, A spacer characterized in that the first portion of the elastomer member is configured and arranged to elastically deform by bending on itself in response to an external force acting on the spacer.

12. In the spacer according to claim 10, A spacer characterized in that the first portion of the elastomer member is configured and arranged so as to be completely housed within the bracket cavity in response to a sufficiently high external force acting on the spacer.

13. A top cover that is attached to the housing of an automotive battery pack and positioned to close the housing, The top cover comprises a plurality of spacers as described in any one of claims 1 to 3, wherein the bracket base of each spacer in the plurality of spacers is attached to the upper surface of the top cover, and thereby the spacers protrude from the upper surface of the top cover along the entire height of the spacers.

14. In the top cover described in claim 13, The top cover is characterized in that the plurality of spacers include spacers having different bracket heights from each other.

15. A battery pack provided with the top cover described in claim 13.

16. An assembly comprising a vehicle body and the battery pack described in claim 15, The assembly is characterized in that the battery pack is attached to the underside of the vehicle body, and the distance between the upper surface of the top cover and the underside of the vehicle body is such that when the battery pack is attached to the underside of the vehicle body, a plurality of spacers provided on the top cover are biased.

17. A method for installing a car battery pack, The steps of attaching a plurality of spacers according to any one of claims 1 to 3 to the upper surface of the top cover of an automotive battery pack, A method comprising a step of attaching a battery pack, on which the top cover having the spacers is provided, to the underside of a vehicle body, characterized in that, in accordance with the attachment of the battery pack, the first portion of the elastomer members of the plurality of spacers undergoes initial deformation, thereby forming an initial biasing state of the spacers.

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