A battery pack

Abstract

This utility model provides a battery pack, including a lower housing; a cell assembly disposed within the lower housing, comprising multiple stacked cells arranged in the width direction of the cells; a top cover connected to the lower housing and covering the cell assembly; a support member supporting and connected between the cells and the top cover; the support member having a first support portion and a second support portion, the first support portion being fixedly connected to the cells; the top cover being fixedly connected to the second support portion, and the support member shielding the cell's explosion-proof valve from the top cover. By providing a support member between the cells and the top cover, the support member provides support to the top cover, thereby enhancing the strength of the top cover and creating a certain distance between the top cover and the cells, reducing the probability of battery pack failure due to insufficient strength of the top cover; simultaneously, the support member shielding the cell's explosion-proof valve from the top cover protects the top cover and prevents the cell's explosion-proof valve from directly impacting the top cover.

Description

Technical Field

[0001] This utility model relates to the field of power battery technology, and in particular to a battery pack. Background Technology

[0002] With the development of battery technology, batteries are being used more and more widely, and the requirements for battery energy are also getting higher and higher. In existing electric vehicles, the battery pack is the primary energy source, making it a crucial component. The battery pack is typically installed under the seats and bears part of their weight. The battery pack's cover may collapse inwards, potentially leading to battery pack malfunction. Summary of the Invention

[0003] This utility model provides a battery pack to solve the technical problem that the top cover of the battery pack is not strong enough and may collapse inward, causing battery pack failure, thereby improving the overall stability of the battery pack.

[0004] The present invention provides a battery pack comprising: Lower housing; A battery cell assembly, disposed within the lower housing, comprises multiple stacked battery cells, wherein the stacking direction of the battery cells is the thickness direction of the battery cells; The upper cover is connected to the lower housing and covers the top of the battery cell assembly; A support member is provided, which is connected between the battery cell and the top cover. The support member has a first support portion and a second support portion. The first support portion supports the side of the battery cell facing the top cover and is fixedly connected to the battery cell. The side of the top cover facing the battery cell is supported by the second support portion and is fixedly connected to the second support portion. The support member also shields the explosion-proof valve of the battery cell between the top cover and the top cover.

[0005] In one embodiment of the present invention, at least a portion of the battery cells are provided with an explosion-proof valve on the side facing the top cover, the support extends along the stacking direction of the battery cells and spans the explosion-proof valve along the length direction of the battery cells, and an exhaust channel corresponding to the top of the explosion-proof valve is defined between the support and the battery cells.

[0006] In one embodiment of the present invention, the first support portion includes two first support plates, and the second support portion is a second support plate. Along the length direction of the battery cell, the second support plate is connected between the two first support plates. The second support plate arches towards the upper cover relative to the first support portion and spans across the explosion-proof valve.

[0007] In one embodiment of the present invention, along the length of the battery cell, the two first support plates are respectively connected to the second support plate via a connecting plate. The first support plate and the second support plate are arranged in parallel, and the connecting plate is smoothly connected to the first support plate and the second support plate.

[0008] In one embodiment of the present invention, a first curved portion is formed at the connection between the connecting plate and the first support plate, and a second curved portion is formed at the connection between the connecting plate and the second support plate, wherein the bending directions of the first curved portion and the second curved portion are opposite.

[0009] In one embodiment of this utility model, a mica sheet is provided on the side of the explosion-proof valve facing the support member.

[0010] In one embodiment of this utility model, the first support portion is bonded and fixed to the battery cell, and the second support portion is bonded and fixed to the top cover.

[0011] In one embodiment of the present invention, multiple limiting ribs are provided on the side of the first support portion facing the battery cell and on the side of the second support portion facing the upper cover. The multiple limiting ribs are distributed along the length direction of the battery cell, and each limiting rib extends along the thickness direction of the battery cell. A glue-limiting groove is formed between two adjacent limiting ribs.

[0012] In one embodiment of this utility model, multiple limiting ribs are evenly distributed along the length direction of the battery cell.

[0013] In one embodiment of the present invention, the support member includes an integrally formed glass fiber member.

[0014] The beneficial effects of this utility model are as follows: The battery pack proposed in this utility model provides support between the battery cell and the top cover, thereby enhancing the strength of the top cover and reducing the probability of battery pack failure due to insufficient strength of the top cover. At the same time, the support is shielded between the explosion-proof valve of the battery cell and the top cover. When the battery cell experiences thermal runaway, the large amount of high-temperature and high-pressure gas generated inside will not directly impact the top cover through the explosion-proof valve, thus protecting the top cover. Attached Figure Description

[0015] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0016] In the attached diagram: Figure 1 This is an exploded view of a battery pack according to an embodiment of the present invention; Figure 2 This is a partial structural diagram of a battery pack after the lower casing has been removed, according to an embodiment of the present invention. Figure 3 for Figure 2 An explosion diagram; Figure 4 This is a sectional view of the support component.

[0017] The attached figures are labeled as follows: Lower housing 1, battery cell 2, explosion-proof valve 21, upper cover 3, support component 4, first support plate 41, second support plate 42, connecting plate 43, limiting rib 44, glue limiting groove 45, exhaust channel 5, structural adhesive 6. Detailed Implementation

[0018] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0019] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components. In actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0020] In the following description, numerous details are explored to provide a more thorough explanation of embodiments of the present invention. However, it will be apparent to those skilled in the art that embodiments of the present invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring embodiments of the present invention.

[0021] Please see Figure 1 This utility model provides a battery pack, including a lower housing 1 and an upper cover 3 connected to each other. A battery cell assembly is installed inside the lower housing 1, and the upper cover 3 covers the battery cell assembly. The battery cell assembly includes multiple stacked battery cells 2, and the stacking direction of the battery cells 2 is the thickness direction of the battery cells 2.

[0022] like Figure 2 and Figure 3 As shown, to enhance the structural strength of the top cover 3 and prevent its deformation, a support member 4 is provided between the top cover 3 and the battery cell 2. The support member 4 has a first support part and a second support part. The first support part supports the side of the battery cell 2 facing the top cover 3 and is fixedly connected to the battery cell 2; the side of the top cover 3 facing the battery cell 2 is supported by the second support part and is fixedly connected to the second support part. At the same time, the support member 4 shields the explosion-proof valve of the battery cell 2 and the top cover 3, so that when the battery cell 2 experiences thermal runaway, the high-temperature and high-pressure gas generated inside it will not directly impact the top cover 3 through the explosion-proof valve 21, thus effectively protecting the top cover 3.

[0023] The support member 4 is connected between the battery cell 2 and the upper cover 3, and it avoids the terminals of the battery cell 2. That is, the first support part supports the top wall of the battery cell at a non-terminal position. The support member 4 effectively transfers and distributes the external pressure and impact load borne by the upper cover 3 to the battery cell assembly, preventing the upper cover 3 from denting or deforming due to excessive force, and greatly enhancing the structural integrity and impact resistance of the entire battery pack. The support member 4 supports the upper cover 3, enhancing its strength and ensuring that there is always a certain gap between the inner side of the upper cover 3 and the battery cell 2, without affecting the terminals of the battery cell 2. By setting the support member 4 between the battery cell 2 and the upper cover 3, the strength of the entire battery pack is enhanced, providing some support for the passenger cabin seats.

[0024] In some embodiments, such as Figure 2 and Figure 3 As shown, at least a portion of the battery cells 2 are equipped with explosion-proof valves 21 on the side facing the top cover 3. A support member 4 extends along the stacking direction of the battery cells 2 and is elongated. The support member 4 spans the explosion-proof valve 21 along the length of the battery cells 2, defining an exhaust channel 5 above the explosion-proof valve 21 between the support member 4 and the battery cells 2. When a battery cell 2 experiences thermal runaway, a large amount of high-temperature, high-pressure gas is instantly generated inside, causing the explosion-proof valve 21 to open and release pressure. The exhaust channel 5 provides a pre-defined flow path for the high-pressure gas. It can transform the destructive, disorderly jetting into orderly discharge along a predetermined direction, effectively preventing the high-pressure gas flow from directly impacting the top cover 3 or adjacent battery cells 2, thus avoiding some chain reactions of thermal runaway.

[0025] In some embodiments, the first support portion includes two first support plates 41, the two first support plates 41 are arranged in parallel, and directly supported and fixed on the top of the cell 2, and the two first support plates 41 are respectively located on two sides of the explosion-proof valve 21 along the length direction of the cell 2. The second support portion is a second support plate 42, along the length direction of the cell 2, the second support plate 42 is connected between the two first support plates 41, the second support plate 42 arches toward the top cover 3 relative to the first support portion, and spans over the explosion-proof valve 21. The two first support plates 41 and the second support plate 42 are connected to form a structure similar to a "几" shape.

[0026] Two poles are disposed on the side of the cell 2 close to the top cover 3, and the entire support member 4 is located between the two poles, which will not affect the normal connection of the poles.

[0027] The two first support plates 41, the arched second support plate 42 and the top surface of the cell 2 jointly define a continuous exhaust channel 5 with a substantially trapezoidal or arched cross section. The two first support plates 41 and the second support plate 42 are arranged in parallel, the bottom of the first support plate 41 is supported on the top of the cell 2, the two first support plates 41, the second support plate 42 and the top of the cell 2 enclose the exhaust channel 5, and the exhaust channel 5 completely shields and protects the explosion-proof valve 21 below.

[0028] In some embodiments, along the length direction of the cell 2, the two first support plates 41 are respectively connected to the second support plate 42 through the connecting plates 43, the first support plate 41 and the second support plate 42 are arranged in parallel, and the connecting plates 43 are respectively connected with the first support plate 41 and the second support plate 42 in a smooth transition manner. One end of the connecting plate 43 is bent with respect to the first support plate 41, and the other end of the connecting plate 43 is also bent with respect to the second support plate 42. Thus, a continuous and natural curved surface connection is formed between the connecting plate 43 and the first support plate 41 as well as the second support plate 42, which effectively avoids the stress concentration phenomenon. This structural design not only enhances the overall rigidity and stability of the support member 4, but also improves the fit degree with the surface of the cell 2 by expanding the contact area. The bent transition of the connecting plate 43 extends the coverage range of the support member 4 in the length direction of the cell 2, so that a larger support contact area is realized in a limited space, which helps to evenly disperse the stress generated by the volume change of the cell 2 during the charging and discharging process, and improves the safety and durability of the overall structure.

[0029] The bending directions between the connecting plate 43 and the first support plate 41 and between the connecting plate 43 and the second support plate 42 may be the same or different, as long as the first support plate 41 does not shield the explosion-proof valve 21.

[0030] In some embodiments, such as Figure 4As shown, along the length direction of the cell 2, the two first support plates 41 are respectively connected to the second support plate 42 through the connection plates 43, forming an integrated support frame. The first support plate 41 and the second support plate 42 are parallel to each other, and the connection plate 43 serves as a transition bridge between the two. Specifically, at the connection between the connection plate 43 and the first support plate 41, a first bent portion is formed through a smooth arc transition; correspondingly, at the connection between the connection plate 43 and the second support plate 42, a second bent portion is formed. The bending directions of the first bent portion and the second bent portion are opposite. That is, the two first support plates 41, the two connection plates 43 and the second support plate 42 form a structure similar to a "several" shape. The two first support plates 41 extend in opposite directions along the length direction of the cell 2, and this multi-segment bent structure further extends the effective contact area of the support member 4 and enhances stability. At the same time, the bends in opposite directions enhance the rigidity of the support member 4 in the height direction of the cell 2, effectively preventing the support member 4 from twisting or deforming.

[0031] In some embodiments, a mica sheet is provided on the side of the explosion-proof valve 21 facing the support member 4. As an excellent inorganic insulating material, the mica sheet has properties such as high temperature resistance, high insulation, and high flame retardancy. Providing the mica sheet on the explosion-proof valve, on the one hand, when a single cell 2 experiences thermal runaway, the mica sheet can effectively block high-temperature ejecta from directly impacting the upper support member 4 and the upper cover 3, delaying the escalation of thermal runaway; on the other hand, it has a lateral isolation effect. Through its low thermal conductivity, the mica sheet can reduce heat transfer and thermal radiation from the thermally runaway cell 2 to adjacent cells 2, thereby delaying or preventing the occurrence of thermal spread and increasing the response time for system safety warning and disposal.

[0032] In some embodiments, both between the first support part and the cell 2 and between the second support part and the upper cover 3 are fixed by bonding. Specifically, high-performance structural adhesive 6 is applied between the first support part and the upper surface of the cell 2, and between the second support part and the inner wall of the upper cover 3 of the battery pack. This bonding structure tightly combines the support member 4, the cell 2 and the upper cover 3 into a single whole, ensuring that no relative displacement occurs under vehicle vibration and impact conditions. The structural adhesive 6 usually also has certain thermal conductivity, which helps to promote uniform heat distribution.

[0033] In some embodiments, such as Figure 4As shown, multiple limiting ribs 44 are provided on the side of the first support facing the battery cell 2 and the side of the second support facing the upper cover 3. These limiting ribs 44 are distributed along the length of the battery cell 2, and each limiting rib 44 extends along the thickness direction of the battery cell 2. Adhesive-limiting grooves 45 are formed between adjacent limiting ribs 44. When the support member 4 is bonded to the battery cell 2 and the upper cover 3, the limiting ribs 44 act as stop surfaces, ensuring that after applying a certain pressure, a gap determined by the height of the limiting ribs 44 is maintained between the support member 4 and the bonding surface, avoiding the problem of excessively thick or thin adhesive layers. During the pressing process, excess adhesive is squeezed into the adhesive-limiting grooves 45.

[0034] In some embodiments, the cross-sectional shape of the limiting rib 44 is arc-shaped. When the support member 4 is subjected to stress caused by vibration, impact, or thermal expansion and contraction, the continuous arc-shaped surface can achieve a smooth transition and uniform distribution of stress, effectively avoiding stress concentration at the edge of the rib, thereby greatly improving the fatigue resistance and long-term reliability of the adhesive layer. At the same time, during the bonding and pressing process, the surface of the arc-shaped limiting rib 44 is smoother, resulting in less resistance to the flow of the adhesive. This facilitates the smoother flow of the adhesive to the limiting groove 45 between adjacent ribs when it is squeezed, ensuring the uniformity of the adhesive distribution.

[0035] In some embodiments, multiple limiting ribs 44 are evenly distributed along the length direction of the battery cell 2.

[0036] In some embodiments, the support member 4 includes an integrally molded glass fiber component, meaning the support member 4 can be made of glass fiber, manufactured using an integral molding process. The integrally molded glass fiber support member 4 offers advantages such as light weight, high strength, high rigidity, insulation safety, and dimensional stability. While meeting the required mechanical strength and deformation resistance, it also achieves lightweight design. Glass fiber has a low coefficient of thermal expansion and maintains shape and dimensional stability under different temperature and humidity conditions, ensuring the long-term stability of the bonding interface between the support member 4 and the battery cell 2 and the top cover 3, preventing deformation due to thermal expansion and contraction.

[0037] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A battery pack, characterized in that, include: Lower housing; A battery cell assembly, disposed within the lower housing, comprises multiple stacked battery cells, wherein the stacking direction of the battery cells is the thickness direction of the battery cells; The upper cover is connected to the lower housing and covers the top of the battery cell assembly; A support member is provided, which is connected between the battery cell and the top cover. The support member has a first support portion and a second support portion. The first support portion supports the side of the battery cell facing the top cover and is fixedly connected to the battery cell. The side of the top cover facing the battery cell is supported by the second support portion and is fixedly connected to the second support portion. The support member also shields the explosion-proof valve of the battery cell between the top cover and the top cover.

2. The battery pack according to claim 1, characterized in that: At least a portion of the battery cells are provided with an explosion-proof valve on the side facing the top cover. The support extends along the stacking direction of the battery cells and spans the explosion-proof valve along the length direction of the battery cells. An exhaust channel corresponding to the top of the explosion-proof valve is defined between the support and the battery cells.

3. The battery pack according to claim 2, characterized in that: The first support portion includes two first support plates, and the second support portion is a second support plate. Along the length direction of the battery cell, the second support plate is connected between the two first support plates. The second support plate arches towards the top cover relative to the first support portion and spans across the explosion-proof valve.

4. The battery pack according to claim 3, characterized in that: Along the length of the battery cell, the two first support plates are respectively connected to the second support plate via connecting plates. The first support plates and the second support plates are arranged in parallel, and the connecting plates are smoothly connected to the first support plates and the second support plates.

5. The battery pack according to claim 4, characterized in that: The connection between the connecting plate and the first support plate forms a first curved portion, and the connection between the connecting plate and the second support plate forms a second curved portion. The bending directions of the first curved portion and the second curved portion are opposite.

6. The battery pack according to claim 2, characterized in that: A mica sheet is provided on the side of the explosion-proof valve facing the support member.

7. The battery pack according to any one of claims 1-6, characterized in that: The first support portion is bonded and fixed to the battery cell, and the second support portion is bonded and fixed to the top cover.

8. The battery pack according to claim 7, characterized in that: Multiple limiting ribs are provided on the side of the first support portion facing the battery cell and on the side of the second support portion facing the top cover. The multiple limiting ribs are distributed along the length direction of the battery cell, and each limiting rib extends along the thickness direction of the battery cell. A glue-limiting groove is formed between two adjacent limiting ribs.

9. The battery pack according to claim 8, characterized in that: The multiple limiting ribs are evenly distributed along the length of the battery cell.

10. The battery pack according to claim 1, characterized in that: The support component includes a one-piece molded fiberglass component.

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