Battery pack shell assembly and battery pack

Abstract

The utility model relates to the technical field of batteries, and particularly provides a battery pack shell assembly and a battery pack. Wherein the battery pack shell assembly comprises a box body, a box cover, a fastener and a bushing, the box body is provided with a second through hole, the box cover is provided with a first through hole, and the fastener penetrates through the second through hole and the first through hole to connect the box body with the box cover; the lining is arranged in the first through hole, part of the structure of the lining protrudes out of the first through hole in the direction away from the box body, the protruding part abuts against the fastener, and the size of the protruding part is h; the elasticity modulus of the box cover is a1, the elasticity modulus of the fastener is a2, and the formula that (a2-a1) / h is larger than or equal to 200 Gpa / mm and smaller than or equal to 300 Gpa / mm is met. In the invention, the lining part structure is supported between the fastener and the box cover, so that the box cover is prevented from being crushed by the fastener due to insufficient hardness. Specifically, when (a2-a1) / h meets the condition that (a2-a1) / h is larger than or equal to 200 Gpa / mm and smaller than or equal to 300 Gpa / mm, the connecting strength of the fasteners to the box cover and the box body can be guaranteed, and meanwhile the fasteners can be prevented from crushing the box cover.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and specifically proposes a battery pack housing assembly and a battery pack. Background Technology

[0002] Currently, in order to reduce their weight, some battery packs are made of composite materials in at least part of their structure, such as the battery pack outer casing. However, this makes the battery pack outer casing less rigid, and the lid can easily be damaged when the lid and casing are tightened with metal bolts and nuts. Utility Model Content

[0003] The purpose of this application is to solve at least some of the technical problems mentioned above, and this purpose is achieved through the following technical solutions:

[0004] In a first aspect, this application proposes a battery pack housing assembly, which includes a cover, a housing, fasteners, and a bushing. The cover has a first through hole, the housing has a second through hole, and the fasteners pass through the first and second through holes to connect the housing and the cover. The bushing is located in the first through hole, and a portion of its structure protrudes from the first through hole in a direction away from the housing, and the protruding portion abuts against the fastener. The size of the protruding portion is h. The elastic modulus of the cover is a1, the elastic modulus of the fastener is a2, and both satisfy 200Gpa / mm≤(a2-a1) / h≤300Gpa / mm.

[0005] The technical solution proposed in this application has at least the following technical effects:

[0006] In this application, the first through hole of the cover is provided with a bushing. The bushing covers the main body of the fastener. The bushing protrudes from the surface of the cover away from the box body and abuts against the limiting part of the fastener. That is, the bushing part of the structure supports the fastener and the cover, preventing the cover from being crushed by the fastener due to insufficient hardness. Specifically, when (a2-a1) / h satisfies 200Gpa / mm≤(a2-a1) / h≤300Gpa / mm, the connection strength of the fastener to the cover and the box body can be guaranteed, while preventing the fastener from damaging the cover. Attached Figure Description

[0007] To better integrate the content illustrated in the accompanying drawings with the description of the specific embodiments, a brief introduction to the drawings is provided below. It is understood that the accompanying drawings mentioned below are merely schematic illustrations of some embodiments of the relevant technical solutions and the technical solutions of this application. Without creative effort, those skilled in the art can create drawings illustrating other embodiments.

[0008] Specifically, the annotations for the accompanying drawings are as follows:

[0009] Figure 1This is a schematic diagram of the overall structure of the battery pack housing assembly described in some embodiments of this application;

[0010] Figure 2 This is a partial structural cross-sectional view of the battery pack housing assembly described in some embodiments of this application;

[0011] Figure 3 This is a schematic diagram of the structure of the bushing described in some embodiments of this application;

[0012] Figure 4 This is a partial structural diagram of the box lid described in some embodiments of this application;

[0013] Figure 5 This is a cross-sectional schematic diagram of the box cover and bushing described in some embodiments of this application.

[0014] Specifically, the annotations for the figure marks in the specification are as follows:

[0015] 10. Box cover; 101. First through hole; 102. Flanged edge; 20. Box body; 30. Fastener; 301. Limiting part; 40. Bushing; 402. Notch; 403. Gap; 50. Seal; 60. Washer; 70. Nut. Detailed Implementation

[0016] To make the embodiments of this application clearer, they will be described below in conjunction with the accompanying drawings. It is to be understood that the content mentioned below is only a partial embodiment of this application, while the complete list of all embodiments is provided. Therefore, other embodiments obtained based on the following embodiments without any inventive effort all fall within the protection scope of this application.

[0017] It should be understood that the terminology used herein is for the purpose of describing specific embodiments only and is not intended to impose strict limitations on the technical solutions unless the context clearly indicates otherwise. For example, the use of "a," "an," and "the" to modify a feature does not preclude the possibility that the feature may be plural in other embodiments.

[0018] It should be understood that the terms "comprising," "including," and "having" are open-ended, indicating the presence of the stated features but not excluding the possibility of other features in the embodiment. Similarly, the use of terms such as "first," "second," etc., to describe multiple features only indicates the distinction between one feature and another, and such terms do not imply order or sequence unless explicitly stated in the context.

[0019] It should be understood that, unless the context clearly indicates otherwise, the terms "setup," "connection," and "installation" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integrated connection; they can refer to a direct connection or an indirect connection via a medium. Those skilled in the art will understand the specific meaning of these terms in this document based on the specific circumstances.

[0020] In addition, for ease of description, the text will use terms of spatial relative relationship to describe the position of one feature relative to another feature, such as "inner", "outer", "end", "side", "upper", "middle", "lower", "high", "low", "axial", "circumferential", "radial", "horizontal", "vertical", "first direction", "second direction", etc. It can be understood that the spatial relative relationship between two features should include other specific situations besides those shown in the accompanying drawings of the specification.

[0021] The embodiments of this application are described below with reference to the accompanying drawings. It can be understood that the technical features involved in the different embodiments described below can be combined with each other as long as they do not conflict with each other.

[0022] Firstly, referring to Figures 1 to 5 ,in, Figure 2 and Figure 5 The main features of this embodiment are representatively illustrated. The embodiments of this application propose a battery pack housing assembly, which includes a cover 10, a housing 20, a fastener 30, and a bushing 40. The cover 10 has a first through hole 101, and the housing 20 has a second through hole. The fastener 30 passes through the first through hole 101 and the second through hole to connect the housing 20 and the cover 10. The bushing 40 is disposed in the first through hole 101, and a portion of its structure protrudes from the first through hole 101 in a direction away from the housing 20, and the protruding portion abuts against the fastener 30. The size of the protruding portion is h. The elastic modulus of the cover 10 is a1, and the elastic modulus of the fastener 30 is a2, and both satisfy 200Gpa / mm≤(a2-a1) / h≤300Gpa / mm.

[0023] In this embodiment, a bushing 40 is provided in the first through hole 101 of the cover 10. The bushing 40 covers the main body of the fastener 30. The bushing 40 protrudes from the surface of the cover 10 away from the box body 20 and abuts against the limiting part 301 of the fastener 30. That is, the bushing 40 partially supports the structure between the fastener 30 and the cover 10, preventing the cover 10 from being crushed by the fastener 30 due to insufficient hardness. Specifically, when (a2-a1) / h satisfies 200Gpa / mm≤(a2-a1) / h≤300Gpa / mm, the connection strength of the fastener 30 to the cover 10 and the box body 20 can be guaranteed, while preventing the fastener 30 from damaging the cover 10.

[0024] It should be noted that the elastic modulus is a physical quantity that describes a material's ability to resist deformation during the elastic deformation stage. It is defined as the ratio of stress to strain under uniaxial stress. It is an important indicator of a material's stiffness; the higher the value, the stronger the material's resistance to elastic deformation. It should be understood that the higher the elastic modulus of an object, the greater its hardness, and the greater the force required to crush it.

[0025] Therefore, the larger a2-a1 is, the harder the fastener 30 is, and the less hard the cover 10 is. The cover 10 is more easily crushed. Therefore, the protruding part of the bushing 40 needs to be larger, that is, h needs to be larger, so as to realize the support of the bushing 40 for the cover 10. The pressure on the cover 10 is relieved by the deformation of the bushing 40 itself.

[0026] More specifically, when (a2-a1) / h < 200 Gpa / mm, i.e. a2-a1 is small and h is large, this may affect the fixed connection between the housing 20 and the cover 10, resulting in poor sealing. When (a2-a1) / h > 300 Gpa / mm, i.e. a2-a1 is large and h is small, the bushing 40 fails to provide effective support, and the fastener 30 may damage the cover 10.

[0027] Optionally, the bushing 40 is made of a soft material such as rubber.

[0028] In some embodiments, refer to Figure 1 and Figure 4 Key reference Figure 4 The distance between the first through hole 101 and the edge of the cover 10 is d, and satisfies 2mm≤d≤10mm.

[0029] It should be noted that the cover 10 has multiple first through holes 101, and the body 20 has multiple second through holes. Each of the first through holes 101 corresponds to one of the second through holes and is secured by multiple fasteners 30. Taking the cover 10 as an example, the center of the cover 10 is arched and cooperates with the body 20 to form a battery housing space. The edge of the cover 10 has a flange 102 for opening the first through holes 101. Given a fixed battery pack volume, if the size of the flange 102 is made smaller (i.e., the dimension d of the first through hole 101 and the edge of the cover 10 is smaller), the arched area of ​​the cover 10 will be larger, thus ensuring a larger battery housing space and improving the battery volumetric energy density.

[0030] Therefore, when d satisfies 2mm≤d≤10mm, the volumetric energy density of the battery pack can be increased. At the same time, the strength of the edge of the cover 10 will be reduced. Therefore, in order to prevent damage to the cover 10, the value of h needs to be increased.

[0031] In some embodiments, refer to Figure 2 A sealing element 50 is provided between the box body 20 and the box cover 10.

[0032] In this embodiment, the sealing element 50 can not only improve the sealing performance between the cover 10 and the box body 20, but also reduce the pressure on the cover 10 during the fastener 30 fixing process, thus reducing the value of h.

[0033] Optionally, the seal 50 is a soft sealing strip.

[0034] In some embodiments, along the radial direction of the first through hole 101, the ratio of the thickness of the bushing 40 to the diameter of the first through hole 101 is b, and satisfies 0.1≤b≤0.3.

[0035] In this embodiment, the greater the proportion of the thickness of the bushing 40 in the first through hole 101, that is, when b satisfies 0.1≤b≤0.3, the better the support of the bushing 40, and thus the value of h can be reduced.

[0036] In some embodiments, refer to Figure 4 The distance between two adjacent first through holes 101 is c, and satisfies 70mm≤c≤110mm.

[0037] In this embodiment, when the distance between two adjacent first through holes 101 is small, that is, when 70mm≤c≤110mm, there are more fasteners 30 to fix the cover 10 and the box body 20, and the fixing effect is better, but the stress is more concentrated, so the value of h needs to be increased.

[0038] In some embodiments, refer to Figure 2 and Figure 3 The bushing 40 has a folded edge along its circumference at one end away from the housing 20. The fastener 30 has a limiting part 301. A washer 60 is provided between the limiting part 301 and the folded edge. The folded edge abuts against the limiting part 301 through the washer 60.

[0039] Specifically, the folded edge of bushing 40 is not shown in the figure.

[0040] In this embodiment, the folded edge abuts against the surface of the box cover 10 and the gasket 60, increasing the contact area between the folded edge and the gasket 60 and dispersing the pressure on the box cover 10.

[0041] It should be understood that in other embodiments, it is also preferable to not provide a folded edge for the bushing 40.

[0042] In some embodiments, refer to Figure 5 There is a gap 403 between the end of the bushing 40 facing the box body 20 and the surface of the box cover 10 facing the box body 20.

[0043] It should be noted that in some embodiments, before the fastener 30 locks the cover 10 and the box body 20, the bushing 40 may have a gap 403 with the surface of the cover 10. When the fastener 30 starts to fix, the gap 403 provides space for the bushing 40 to deform downwards, so as to prevent the bushing 40 from extending from the first through hole 101 toward the side of the box body 20 and squeezing the seal 50, which would make the sealing between the box body 20 and the cover 10 worse.

[0044] It should be understood that, in some other embodiments, it is also desirable for the bushing 40 to have a gap 403 between the cover 10 and the body 20 after the fastener 30 locks the cover 10 and the body 20 together.

[0045] In some embodiments, refer to Figure 3 The bushing 40 has a notch 402.

[0046] In this embodiment, the notch 402 provides more deformation space for the bushing 40, and h can be set to be larger.

[0047] In some embodiments, the elastic modulus of the bushing 40 is a3, and satisfies 120Gpa≤a3≤200Gpa, and / or 7Gpa≤a1≤15Gpa, and / or 70Gpa≤a2≤210Gpa, and / or 0.2mm≤h≤0.8mm.

[0048] In this embodiment, a1 can be any one of 120Gpa, 130Gpa, 140Gpa, 150Gpa, 160Gpa, 170Gpa, 180Gpa, 190Gpa and 200Gpa or a range between any two of these values.

[0049] In addition, a2 can be any one of 7Gpa, 8Gpa, 9Gpa, 10Gpa, 11Gpa, 12Gpa, 13Gpa, 14Gpa and 15Gpa or a range between any two of these values.

[0050] In addition, a3 can be any one of 70Gpa, 80Gpa, 90Gpa, 100Gpa, 110Gpa, 120Gpa, 130Gpa, 140Gpa, 150Gpa, 160Gpa, 170Gpa, 180Gpa, 190Gpa, 200Gpa and 210Gpa or a range between any two of these values.

[0051] In addition, h can take any one of the following values: 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, and 0.8mm, or a range between any two of these values.

[0052] Secondly, this application proposes a battery pack including a battery and a battery pack housing assembly as described in the first aspect, wherein the battery is housed inside the battery pack housing assembly.

[0053] Therefore, the battery pack of the second aspect possesses all the technical effects of the battery pack housing assembly of the first aspect, and its specific technical effects will not be elaborated here. It should be understood that the battery pack of this embodiment also includes other components, such as a protective circuit board, which will not be described further.

[0054] Optionally, the battery proposed in this embodiment may be, but is not limited to, a pouch battery, a cylindrical battery, a prismatic battery, etc.

[0055] In particular, the term "and / or" in this application should be understood as follows:

[0056] In the first case, the term “and / or” between the first subject and the second subject includes any of the following meanings: (1) only the first subject; (2) only the second subject; and (3) both the first subject and the second subject.

[0057] In the second case, the term "and / or" between the last two of three or more subjects means including at least any one of the subjects. For example, "first subject, second subject and / or third subject" has the same meaning as "first subject and / or second subject and / or third subject", specifically including the following combinations: (1) only the first subject; (2) only the second subject; (3) only the third subject; (4) first subject and second subject and no third subject; (5) first subject and third subject and no second subject; (6) second subject and third subject and no first subject; and (7) first subject, second subject and third subject;

[0058] Furthermore, the character " / " in this application indicates that the objects before and after it are in an "or" relationship.

[0059] Finally, although the embodiments of this application have been described above in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the concept of this application, and such modifications and variations all fall within the scope of protection of this application.

Claims

1. A battery pack housing assembly, comprising: Includes a lid (10), a body (20), fasteners (30) and bushings (40). The lid (10) has a first through hole (101), the body (20) has a second through hole, and the fasteners (30) pass through the first through hole (101) and the second through hole to connect the body (20) and the lid (10). The bushing (40) is provided in the first through hole (101), and part of its structure protrudes from the first through hole (101) in a direction away from the box body (20), and the protruding part abuts against the fastener (30), and the size of the protruding part is h; The elastic modulus of the cover (10) is a1, and the elastic modulus of the fastener (30) is a2, and both satisfy 200Gpa / mm≤(a2-a1) / h≤300Gpa / mm.

2. The battery pack enclosure assembly of claim 1, wherein, The distance between the first through hole (101) and the edge of the box cover (10) is d, and satisfies 2mm≤d≤10mm.

3. The battery pack enclosure assembly of claim 1, wherein, A sealing element (50) is provided between the box body (20) and the box cover (10).

4. The battery pack enclosure assembly of claim 1, wherein, Along the radial direction of the first through hole (101), the ratio of the thickness of the bushing (40) to the diameter of the first through hole (101) is b, and satisfies 0.1≤b≤0.

3.

5. The battery pack enclosure assembly of claim 1, wherein, The distance between two adjacent first through holes (101) is c, and satisfies 70mm≤c≤110mm.

6. The battery pack enclosure assembly of claim 1, wherein, The bushing (40) has a folded edge along its circumference at one end away from the housing (20), and the fastener (30) has a limiting part (301). A washer (60) is provided between the limiting part (301) and the folded edge, and the folded edge abuts against the limiting part (301) through the washer (60).

7. The battery pack enclosure assembly of claim 3, wherein, There is a gap (403) between one end of the bushing (40) facing the box body (20) and the surface of the box cover (10) facing the box body (20).

8. The battery pack enclosure assembly of claim 1, wherein, The bushing (40) is provided with a notch (402).

9. The battery pack enclosure assembly of any one of claims 1 to 8, wherein, The elastic modulus of the bushing (40) is a3, and satisfies 120Gpa≤a3≤200Gpa, and / or 7Gpa≤a1≤15Gpa, and / or 70Gpa≤a2≤210Gpa, and / or 0.2mm≤h≤0.8mm.

10. A battery pack, characterized by, It includes a battery and a battery pack housing assembly as described in any one of claims 1 to 9, wherein the battery is housed inside the battery pack housing assembly.

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