A structure, battery pack, and vehicle for improving battery pack vibration noise.

Abstract

The present invention discloses a structure, a battery pack and a vehicle for improving the vibration noise of a battery pack, the structure comprising a rigid bracket arranged in the middle of the battery pack and spring brackets arranged around the battery pack, wherein the rigid bracket is welded to the upper cover of the battery pack, each of the spring brackets is welded to the upper cover of the battery pack, the top of the rigid bracket has a first welding screw, the top of each spring bracket has a second welding screw, the first welding screw and the second welding screw are used to connect to the lower body of the vehicle, wherein there is a set pre-compression amount between the rigid bracket and the lower body to generate a shock-absorbing pre-tightening force. The present invention provides strong support for the middle of the battery pack by combining the rigid bracket arranged in the middle of the battery pack and the spring brackets arranged around it, thereby achieving a significant improvement in the noise reduction effect.

Description

Technical Field

[0001] The present invention relates to the fields of battery packs and electric vehicles, and in particular to a structure for improving vibration noise of a battery pack, a battery pack having the structure, and a vehicle. Background Art

[0002] Figures 1 to 3 The figure shows a typical structure of a battery pack of an electric vehicle. The battery pack 10' consists of a bottom plate 11', an upper cover 12', and a battery module 13'. The battery pack has connection points 14' on the four sides, which are connected to the lower body of the electric vehicle 20' by screws 30'.

[0003] While driving, if Figure 4 As shown, the vibration of the battery pack will generate noise, which will be transmitted into the car compartment, bringing a bad riding experience. Chinese patent document CN1482971A discloses a shock absorption solution for electric vehicle battery packs, which arranges shock absorbing springs at the four corners between the lower body and the battery pack to achieve a shock absorption effect.

[0004] The existing shock-absorbing spring solution has reduced the battery pack noise to a certain extent, but there is still discernible noise, which has not achieved the ideal effect. In the process of implementing the invention, the inventors found that this is not because the selection or layout of the shock-absorbing spring in engineering is not optimal, but because there are other noise sources. Summary of the invention

[0005] The object of the present invention is to provide a structure for improving the vibration noise of a battery pack, so as to enhance the noise reduction effect of the battery pack during movement.

[0006] Another object of the present invention is to provide a battery pack for improving vibration noise, so as to enhance the noise reduction effect of the battery pack during movement.

[0007] Another object of the present invention is to provide a vehicle to enhance the noise reduction effect of the battery pack during movement.

[0008] To this end, on one hand, the present invention provides a structure for improving the vibration noise of a battery pack, characterized in that it includes a rigid bracket arranged in the middle of the battery pack and a plurality of spring brackets arranged around the battery pack, wherein the rigid bracket is welded to the upper cover of the battery pack, and each of the spring brackets is welded to the upper cover of the battery pack, the top of the rigid bracket has a first welding screw, and the top of each spring bracket has a second welding screw, the first welding screw and the second welding screw are used to connect to the lower body of the vehicle, wherein there is a set pre-compression amount between the rigid bracket and the upper cover of the battery pack to generate a shock-absorbing pre-tightening force.

[0009] Furthermore, the spring bracket includes a bottom plate, a top plate, and a shock absorbing spring located between the top plate and the bottom plate and welded to the top plate and the bottom plate.

[0010] Furthermore, the top plate and the bottom plate are each provided with a stamping boss for welding and positioning the shock absorbing spring.

[0011] Furthermore, the rigid bracket comprises a box-mounted bracket body and welding feet symmetrically arranged on both sides of the box-mounted bracket body.

[0012] Furthermore, the box-mounted bracket body and the two welding foot plates are integrally formed sheet metal parts.

[0013] Furthermore, each bending portion of the sheet metal part is provided with a stamping recessed structure.

[0014] Furthermore, the above-mentioned pre-compression amount is 8mm-12mm.

[0015] Furthermore, the spring bracket and the battery pack upper cover are welded by spot welding.

[0016] Furthermore, the above-mentioned plurality of spring brackets are four spring brackets, and the four spring brackets are divided into two pairs, and each pair of spring brackets is symmetrically arranged about the center line of the battery pack cover.

[0017] Furthermore, the battery pack has a plurality of connection points on its four sides, which are connected to the lower body of the vehicle by screws.

[0018] According to another aspect of the present invention, a battery pack is provided, which adopts the above-described structure for improving vibration noise of the battery pack.

[0019] The present invention also provides a vehicle, such as an electric car, which includes a lower body and a battery pack arranged below the bottom of the lower body, and the battery pack adopts the structure described above for improving the vibration noise of the battery pack.

[0020] The present invention provides strong pre-compression support for the battery pack, especially the upper cover in the middle of the battery pack, by combining a rigid bracket (i.e., an incompressible bracket) arranged in the middle of the battery pack with spring brackets on all sides, thereby achieving a significantly improved noise reduction effect.

[0021] In addition to the above-described objects, features and advantages, the present invention has other objects, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0023] Figure 1 It is the assembly relationship between existing electric vehicles and battery packs;

[0024] Figure 2 It is a schematic diagram of the structure of an existing battery pack;

[0025] Figure 3 yes Figure 2 A schematic structural diagram of the battery pack along the AA section shown;

[0026] Figure 4 It is a phenomenon that the battery pack of existing electric vehicles transmits vibration noise to the car compartment during operation;

[0027] Figure 5 is a schematic diagram of a structure for improving the vibration noise of a battery pack of an electric vehicle during operation (referred to as a noise reduction structure) according to the present invention;

[0028] Figure 6 is a schematic structural diagram of a shock absorbing spring of a noise reduction structure according to the present invention;

[0029] Figure 7 Shows Figure 6 The internal structure of the shock absorbing spring shown;

[0030] Figure 8 is a schematic structural diagram of a rigid support of a noise reduction structure according to the present invention; and

[0031] Fig. 9 Shows Figure 8 BB section view of the rigid bracket shown. DETAILED DESCRIPTION

[0032] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0033] In the process of implementing the invention, the inventors found that the existing battery pack is fixed by spring tensioning on all sides, and the battery pack (especially the battery pack cover) itself is flat, like a piece of cardboard, and the middle part is relatively weak, forming a "drum head" structure. When the vehicle is moving, the battery pack cover hits the air, and the "drum head" produces a booming noise.

[0034] Figures 5 to 9 Some embodiments according to the invention are shown.

[0035] Combined with reference Figure 5 , Figure 6 and Figure 8The noise reduction structure of the present invention includes a rigid bracket 52 in the middle of the battery pack and a plurality of spring brackets 51 arranged around the battery pack. The four edges of the battery pack have connection points, which are connected to the lower body of the electric vehicle by screws, wherein the rigid bracket 52 is welded to the upper cover of the battery pack, and each of the spring brackets 51 is welded to the upper cover of the battery pack. The top of the rigid bracket has a first welding screw 522, and the top of each spring bracket has a second welding screw 514, wherein the first welding screw 522 and the second welding screw 514 are used to connect to the lower body of the electric vehicle, wherein a set pre-compression amount is provided between the rigid bracket and the upper cover of the battery pack to generate a shock-absorbing pre-tightening force.

[0036] There are various welding methods with the battery pack cover, and resistance spot welding is preferred. In this case, the welding is required to be completed before the battery pack cover is assembled.

[0037] In the present invention, the middle of the battery pack (especially the middle of the upper cover of the battery pack) refers to the position where the vibration is the largest or near it. Figure 3 Near point B on the top cover of the battery pack.

[0038] Since the battery pack cover itself is just a stamped sheet metal (thickness less than 1mm), its own strength is not high, and the middle part of the battery pack cover (near point B) is far away from the connection points D1 and D2 between the two ends of the battery pack cover and the battery pack side beams (parts with greater strength). Therefore, when the battery pack shakes in the vertical direction, the vibration of the middle part of the battery pack cover is relatively greater, and the vibrating middle part of the battery pack cover will "slap" the air, causing a booming noise.

[0039] One possible situation is that the position with the maximum vibration is not suitable for welding a rigid bracket. In this case, a position suitable for installing a rigid bracket nearby is selected. Compared with the installation at the position with the maximum vibration, it also has a noise reduction effect that is not easily distinguished by the senses for passengers. In the present invention, the position with the maximum vibration is obtained by experiment, and empirically, the geometric center of the upper cover can be selected.

[0040] In the present invention, the pre-compression amount is obtained according to the actual situation. Under the premise of achieving the noise reduction effect, the smaller the pre-compression force, the better. In one embodiment, the gap between the upper cover of the battery pack and the lower body is 40mm (such as Figure 3 h), and the middle rigid support height is 51mm (such as Fig. 9 H), the pre-compression amount is 11mm.

[0041] In one embodiment, four spring brackets 51 are used, and the rigid bracket 52 is located on the center line L of the upper cover. The four spring brackets are divided into two pairs and are arranged symmetrically about the center line, such as Figure 5As shown in the figure, due to the structural constraints of the upper cover, one pair of spring brackets are closer together, while the other pair of spring brackets are farther apart. The function of the spring brackets is to dampen and reduce vibration. Without the damping springs, the overall vibration of the battery pack, especially the upper cover of the battery pack, will be more severe.

[0042] In the present invention, springs on all sides tighten the upper cover of the battery pack to form a "drum head". At the same time, the rigid bracket in the middle is installed in a pre-tightened manner, which is equivalent to having a "drumstick" in the center of the "drum head" pressing down on the drum head to stop the sound. In this way, the drum head cannot vibrate under external excitation and is not easy to make sound, thereby achieving the purpose of noise reduction.

[0043] In the present invention, Figure 5 As shown, since the distance between the location where the spring is arranged and the connection point between the battery pack upper cover and the battery pack side beam is relatively close, it is more reasonable to set a spring bracket here. Due to the flexibility of the spring itself, the upper cover will not be plastically deformed while being tensioned.

[0044] Continue to refer Figure 3 , Figure 5 As shown in the figure, in the middle of the upper cover (near point B), since it is far from the connection point between the upper cover and the side beam, and the middle of the upper cover is also the point where the vibration amplitude of the "drum surface" is the largest, the rigid bracket set here can make the "drum surface" in the middle of the upper cover form a large tension while preventing the "drum surface" from plastic deformation. If a spring is still used to press the drum surface in the center of the drum surface, then under certain vibration excitation, the spring will still be compressed and stretched along with the drum surface, and the vibration of the drum surface cannot be completely eliminated.

[0045] Combined with reference Figure 6 The spring bracket 51 includes a top plate 512, a bottom plate 513, and a shock absorbing spring 511 located between the top plate and the bottom plate and welded to the top plate and the bottom plate, wherein the second welding screw 514 is welded and fixed to the top plate 512. The spring bracket structure is lightweight on the one hand, and on the other hand, the bearing area of ​​the upper cover of the battery pack is increased, which helps to avoid local deformation of the upper cover due to stress.

[0046] Preferably, if Figure 7 As shown, the top plate 512 and the bottom plate 513 are respectively provided with stamping bosses 512a and 513a for welding and positioning the shock absorbing spring 511.

[0047] Combined with reference Figure 8 and Fig. 9The rigid bracket 52 includes a box-mounted bracket body 521 and welding foot plates 523 symmetrically arranged on both sides of the box-mounted bracket body, wherein the box-mounted bracket body 521 and the two welding foot plates 523 are integrally formed sheet metal parts. The height H of the middle rigid bracket (for example, H = 51mm) is greater than the gap h between the battery pack cover and the lower body (for example, h = 40mm). On the one hand, the rigid bracket is lightweight, and on the other hand, its symmetrical welding foot plate structure increases the load-bearing area of ​​the battery pack cover, which helps to avoid local deformation of the cover due to stress.

[0048] Preferably, each bending portion of the sheet metal component is provided with a stamped recessed structure 524 (ie, a reinforcing rib formed by stamping) to increase the structural strength and deformation resistance of the sheet metal component.

[0049] The present invention also provides a battery pack, which adopts the above-described structure for improving the vibration noise of the battery pack to enhance the noise reduction effect of the battery pack during movement.

[0050] The present invention also provides a vehicle, such as an electric car, comprising a lower body and a battery pack arranged below the bottom of the lower body, the battery pack adopts the structure described above for improving the vibration noise of the battery pack to enhance the noise reduction effect of the battery pack during movement.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A structure for improving vibration noise of a battery pack, characterized in that: It includes a rigid bracket arranged in the middle of the battery pack and a plurality of spring brackets arranged around the battery pack, wherein: The rigid bracket is welded to the upper cover of the battery pack, and each of the spring brackets is welded to the upper cover of the battery pack. The top of the rigid bracket has a first welding screw, and the top of each of the spring brackets has a second welding screw. The first welding screw and the second welding screw are used to connect with the lower body of the vehicle, wherein a set pre-compression amount is provided between the rigid bracket and the upper cover of the battery pack to generate a shock-absorbing pre-tightening force. The spring brackets on all sides tighten the upper cover of the battery pack to form a drum surface. At the same time, the rigid bracket in the middle is installed in a pre-tightened manner, which is equivalent to having a drumstick in the center of the drum surface pressing down on the drum surface to stop the sound. In this way, the drum surface cannot vibrate and make sound under external excitation, thereby achieving the purpose of noise reduction.

2. The structure for improving vibration noise of a battery pack according to claim 1, characterized in that: The spring bracket comprises a bottom plate, a top plate, and a shock absorbing spring which is located between the top plate and the bottom plate and welded to the top plate and the bottom plate.

3. The structure for improving vibration noise of a battery pack according to claim 2, characterized in that: The top plate and the bottom plate are each provided with a stamping boss for welding and positioning the shock absorbing spring.

4. The structure for improving vibration noise of a battery pack according to claim 1, characterized in that: The rigid bracket comprises a box-mounted bracket body and welding foot plates symmetrically arranged on both sides of the box-mounted bracket body.

5. The structure for improving vibration noise of a battery pack according to claim 4, characterized in that: The box-mounted bracket body and the two welding foot plates are integrally formed sheet metal parts.

6. The structure for improving vibration noise of a battery pack according to claim 1, characterized in that: The pre-compression amount is 8mm-12mm.

7. The structure for improving vibration noise of a battery pack according to claim 1, characterized in that: The plurality of spring supports are four spring supports, and the four spring supports are divided into two pairs, and each pair of spring supports is symmetrically arranged about the center line of the battery pack cover.

8. The structure for improving vibration noise of a battery pack according to claim 1, characterized in that: The battery pack has a plurality of connection points on its four sides, which are connected to the lower body of the vehicle by screws.

9. A battery pack for improving vibration noise, characterized in that: A structure for improving vibration noise of a battery pack comprising any one of claims 1 to 8.

10. A vehicle comprising a lower body and a battery pack disposed below the bottom of the lower body, characterized in that: The battery pack is the battery pack for improving vibration noise according to claim 8.

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