Battery pack

Abstract

The application provides a battery pack, comprising a battery box and a cell stack arranged in the battery box; the battery box comprises a lower box, a cover combined with the lower box, and a pressing strip matched with the outer surface of the cover; the cell stack comprises a plurality of cells arranged side by side and a separator pad arranged on the top of the cells; the cover is provided with a groove recessed towards the lower box, the top of the separator pad abuts against the inner surface of the cover and corresponds to the position of the groove; and the opposite ends of the pressing strip are fixedly connected with the lower box. The application can improve the anti-displacement capability of the cell stack in a vibration scene, avoid hidden dangers such as cell deviation and contact short circuit caused by bonding failure or structural loosening, and ensure the safety of the battery pack.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more particularly to a battery pack. Background Technology

[0002] To improve the space utilization of battery packs in products such as vehicles, battery packs are usually designed as long strips, with mounting points at opposite ends of the battery pack housing for installation and fixation.

[0003] In related technologies, the battery cell stack is fixed in the lower housing by adhesive bonding or insulating tape. When the battery pack is subjected to external vibration, the lack of reliable longitudinal restraint on the battery cell stack can easily cause problems such as battery cell stack failure or busbar breakage. Utility Model Content

[0004] In view of the above, this application aims to provide a battery pack to solve some or all of the technical problems raised in the background art.

[0005] To achieve the above objectives, this application provides a battery pack, including a battery housing and a cell stack disposed within the battery housing; the battery housing includes a lower housing, a cover covering the lower housing, and a pressure strip abutting the outer surface of the cover; the cell stack includes a plurality of cells arranged side by side and a spacer disposed on top of the cells. The cover has a recessed groove facing the lower box body, the top of the spacer abuts against the inner surface of the cover body and corresponds to the position of the groove; the opposite ends of the pressure strip are fixedly connected to the lower box body.

[0006] As can be seen from the above, the battery pack provided in this application has a spacer between the top of the cell stack and the inner surface of the cover, which can provide effective support and insulation protection for the cell stack. The pressure strip added in the groove on the outer surface of the cover can enhance the connection strength between the cover and the lower box, improve the support stability of the spacer, and ensure that the spacer can moderately compress the cell stack, thereby improving the cell stack's resistance to displacement in vibration scenarios, avoiding potential hazards such as cell displacement and short circuits caused by bonding failure or structural loosening, and ensuring the safety of the battery pack. Attached Figure Description

[0007] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0008] Figure 1 This is a schematic diagram of the battery pack structure in an embodiment of this application; Figure 2 This is a cross-sectional view of the battery pack in an embodiment of this application; Figure 3 for Figure 2 A magnified view of a portion of region A in the middle; Figure 4 This is a partial cross-sectional view of the cover in an embodiment of this application; Figure 5 This is a schematic diagram showing the connection between the pressure strip and the lower housing in an embodiment of this application; Figure 6 This is a schematic diagram of the first distribution of grooves on the outer surface of the cover body in an embodiment of this application; Figure 7 This is a schematic diagram of a second distribution of grooves on the outer surface of the cover body in an embodiment of this application; Figure 8 This is a schematic diagram of the third distribution of grooves on the outer surface of the cover in an embodiment of this application.

[0009] Explanation of reference numerals in the attached figures: 1. Lower housing; 101. Flange face; 2. Cover; 201. Inner surface; 202. Outer surface; 210. Groove; 220. Protrusion; 3. Cell stack; 310. Cell; 320. Spacer; 4. Pressing strip; 410. Pressing part; 420. Connecting part; 421. Through hole; 5. Adhesive layer. Detailed Implementation

[0010] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with specific embodiments and the accompanying drawings.

[0011] It should be noted that, unless otherwise defined, the technical or scientific terms used in the embodiments of this application should have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word covers the element or object listed following the word and its equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are only used to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0012] To improve the utilization efficiency of the battery pack in the product installation space, the battery pack can be designed as a rectangular or strip structure, and mounting points can be set at opposite ends of the battery pack housing to achieve the reliability and firmness of the battery pack installation.

[0013] A battery pack may include a battery housing and a stack of battery cells inside. To secure the stacked cells, adhesive materials can be used to directly fix them to the lower housing of the battery housing, or insulating tape can be used to bind them across the top surface of the stacked cells, thus limiting and securing them. However, when products using the aforementioned battery packs experience continuous or severe vibration, both methods of securing them exhibit significant drawbacks. Specifically, the adhesive layer and insulating tape have limited resistance to the dynamic loads generated by vibration, making it difficult to provide reliable support and effective constraint for the stacked cells in the longitudinal direction (i.e., the height of the battery pack). This is especially true for stacked cells located in the middle area of ​​the battery housing. The dynamic loads on the stacked cells may reduce the restraining effect of the adhesive layer or insulating tape, leading to fatigue damage and failure of the adhesive layer, or fatigue fracture of the insulating tape. This could result in the stacked cells detaching from the lower housing, and could even affect the connected busbars, causing them to break and impacting the subsequent use of the battery pack.

[0014] This application provides a battery pack, combined with Figures 1-8 The content shown provides a detailed description of the battery pack.

[0015] A battery pack includes a battery housing and a cell stack 3 disposed within the battery housing; the battery housing includes a lower housing 1, a cover 2 covering the lower housing 1, and a pressure strip 4 abutting the outer surface 202 of the cover 2; the cell stack 3 includes a plurality of cells 310 arranged side by side and spacers 320 disposed on the top of the cells 310; the cover 2 has a groove 210 recessed toward the lower housing 1, the top of the spacer 320 abutting against the inner surface 201 of the cover 2 and corresponding to the position of the groove 210; the opposite ends of the pressure strip 4 are fixedly connected to the lower housing 1.

[0016] Figures 1-3 The displayed content includes a structural schematic diagram, a cross-sectional view, and a partial enlarged view of region A, which can be the distribution of the spacer 320 within the battery pack. Figures 1-3As shown, the battery pack may include a battery housing and a cell stack 3 disposed inside it. The battery housing has a receiving part that can accommodate the cell stack 3, providing centralized placement and protection for the cell stack 3. As the core component of the battery pack, the cell stack 3 may include multiple cells 310 and spacers 320 disposed on top of the multiple cells 310. The multiple cells 310 can store energy during charging and release and provide electrical energy during use.

[0017] Furthermore, the battery housing may include a matching lower housing 1 and a cover 2. For example... Figure 1 and Figure 2 As shown, the lower housing 1 has a cavity, and the battery cell stack 3 can be fixed inside the cavity by bonding or binding, thus achieving stable support. The cover 2 has an inner surface 201 and an outer surface 202 that are arranged opposite each other. The cover 2 covers the lower housing 1, so that the cavity of the lower housing 1 and the inner surface 201 of the cover 2 together form a receiving cavity for accommodating and covering the battery cell stack 3, which can provide effective protection for the battery cell stack 3. This ensures a compact structure between the battery housing and the battery cell stack 3, while also achieving good protection for the battery cell stack 3.

[0018] For example, both the lower housing 1 and the cover 2 can be made of metal to ensure that the battery pack has sufficient strength and improve the protection of the cell stack 3.

[0019] Furthermore, since the lower casing 1 and cover 2 of the battery pack are made of metal, when the cell stack 3 is dislodged from its original installation position, causing the electrode terminals of the cell 310 to come into contact with the lower casing 1 and / or cover 2, it may lead to a short circuit or other safety hazards in the cell stack 3. To address the aforementioned problem, the battery pack provided in this application includes a pressure strip 4 in the battery casing and a spacer 320 in the cell stack 3. The pressure strip 4 and the spacer 320 work together to provide limiting support and insulation protection for the cell stack 3.

[0020] Specifically, the outer surface 202 of the cover 2 is provided with a groove 210 recessed towards the lower housing 1, so that the inner surface 201 of the cover 2 forms a pressing area corresponding to the groove 210; when the cover 2 and the lower housing 1 are in a closed state, the spacer 320 of the cell stack 3 is located inside the battery housing; wherein, the bottom surface of the spacer 320 abuts against the shoulder of the top surface of a plurality of cells 310 in the cell stack 3, and the shoulder of the cell 310 is the area of ​​its top surface near the edge; the spacer 320 The top surface of 0 contacts the compression area of ​​the inner surface 201 of the cover 2, so that the spacer 320 forms a bidirectional support between the two; the pressure strip 4 is located in the groove 210, which can position the pressure strip 4, reduce the positioning difficulty of the pressure strip 4 assembly, and avoid the connection position from being offset; and the pressure strip 4 is in contact with the outer surface 202 of the cover 2 in the groove 210, and the opposite ends of the pressure strip 4 are respectively connected to the opposite sides of the lower box 1, so that the pressure strip 4 can press the cover 2 tightly and fix it above the lower box 1.

[0021] More specifically, when the pressure strip 4 is used to fix the cover 2, the pressure applied by the pressure strip 4 to the cover 2 in the groove 210 can act on the spacer 320 through the squeezing area of ​​the inner surface 201 of the cover 2, so that the squeezing area of ​​the inner surface 201 of the cover 2 can press the spacer 320 tightly against the top of the cell stack 3. Therefore, on the one hand, the cooperation between the pressure strip 4 and the spacer 320 can moderately squeeze and limit the cell 310, thereby enhancing the ability of the cell stack 3 to resist vibration in the height direction of the housing, and preventing problems such as connection failure or positional displacement caused by shaking of the cell stack 3; on the other hand, the application of the spacer 320 can form a stable insulating gap between the inner surface 201 of the cover 2 and the top of the cell stack 3, which can avoid short circuit problems caused by accidental contact between the electrode terminals and the cover 2, and ensure the safety and overall quality of the battery pack.

[0022] In some embodiments, the inner surface 201 of the cover 2 is provided with a protrusion 220 for squeezing the spacer 320. The protrusion 220 protrudes toward the lower housing 1 and is disposed opposite to the groove 210. The spacer 320 is connected to the surface of the protrusion 220.

[0023] Figure 4 The content shown is a partial sectional view of cover 2; such as Figure 3 and Figure 4As shown, in order to effectively compress the spacer 320 and enhance the support effect on the battery cell stack 3, in addition to the groove 210 on its outer surface 202 for positioning and accommodating the pressure strip 4, the cover 2 in this application also has a protrusion 220 on its inner surface 201. This reduces the distance between the inner surface 201 of the cover 2 and the top of the battery cell stack 3, improving the compression effect of the spacer 320. The protrusion 220 protrudes from the inner surface 201 of the cover 2 towards the lower housing 1 and is positioned opposite to the groove 210. Thus, when the pressure strip 4 is placed in the groove 210 and has pressure, the pressure can be transmitted to the spacer 320 through the protrusion 220, thereby enhancing the support stability of the spacer 320 within the battery housing.

[0024] For example, the groove 210 on the outer surface 202 and the protrusion 220 on the inner surface 201 of the cover 2 can be formed by a stamping process, which is beneficial to improving the production efficiency of the cover 2 and reducing the manufacturing cost.

[0025] In some embodiments, at least two grooves 210 are provided, with at least one groove 210 extending along the length direction of the lower housing 1; and / or at least one groove 210 extending along the width direction of the lower housing 1.

[0026] Specifically, such as Figure 2 and Figure 3 As shown, the groove 210 is designed to precisely position the pressure strip 4 and, in conjunction with the pressure strip 4, apply stable pressure to the spacer 320, thereby enhancing the connection strength and vibration resistance of the cell stack 3 within the lower housing 1. By appropriately adjusting the number of grooves 210, matching installation positions can be provided for a corresponding number of pressure strips 4, thus optimizing the fixing effect of the pressure strip 4 on the cover 2 and the spacer 320.

[0027] For example, to facilitate a clear explanation of the structure and connection relationship of each component of the battery pack in conjunction with the accompanying drawings, the length direction of the lower housing 1 can be defined as the x-direction, and the width direction of the lower housing 1 can be defined as the y-direction, thereby reducing the complexity of understanding the accompanying drawings.

[0028] Example 1: Figure 6 The displayed content is a schematic diagram of the first distribution of the grooves 210 on the outer surface 202 of the cover 2. For example... Figure 6 As shown, the outer surface 202 of the cover 2 can be provided with two parallel grooves 210, both of which extend along the length of the lower box 1. At this time, the pressure strip 4 located in the groove 210 crosses the cover 2 along the length of the lower box 1 and is fixedly connected to the opposite ends of the lower box 1, ensuring the fixing effect of the cover 2.

[0029] Example 2: Figure 7 The illustration shows a second distribution of the grooves 210 on the outer surface 202 of the cover 2. For example... Figure 7 As shown, the outer surface 202 of the cover 2 can be provided with two parallel grooves 210, both of which extend along the width direction of the lower box 1. At this time, the pressure strip 4 located in the groove 210 crosses the cover 2 along the width direction of the lower box 1 and is fixedly connected to the opposite sides of the lower box 1 to ensure the fixing effect of the cover 2.

[0030] Example 3: Figure 8 The illustration shows a third type of distribution of the groove 210 on the outer surface 202 of the cover 2. For example... Figure 8 As shown, the outer surface 202 of the cover 2 can be provided with two types of grooves 210, and each type of groove 210 can be provided with two, one of which extends along the width direction of the lower box 1, and the other extends along the width direction of the lower box 1. The corresponding pressure strips 4 located in the grooves 210 all span the cover 2 and are fixedly connected to the lower box 1 to enhance the pressing effect on the cover 2 and the spacer 320.

[0031] In some embodiments, the spacer 320 is foam, and the spacer 320 is compressibly disposed between the protrusion 220 and the cell 310.

[0032] Specifically, because foam is lightweight, low-cost, and has good compressibility and resilience, by using foam as the spacer 320 between the protrusion 220 and the battery cell 310, it can buffer and dampen vibrations during vibration, ensuring that the spacer 320 can provide continuous and stable contact pressure to the inner surface 201 of the cover 2 and the battery cell stack 3.

[0033] In some embodiments, the cell 310 is a prismatic cell, and the bottom surface of the spacer 320 is adhered to the top surface of two prismatic cells that are spaced apart from each other.

[0034] Specifically, since the square-shell battery cell 310 has a regular structure, it is easy to arrange it closely. Using square-shell battery cells to form a battery cell stack 3 can improve the space utilization inside the battery box. Moreover, the top of the square-shell battery cell can provide a stable support point for the spacer 320, thereby improving the limiting effect of the spacer 320 on the battery cell stack 3.

[0035] In addition, regarding the spacer 320, the bottom surface of the spacer 320 is adhered to the top surface of the two relatively spaced square-shell cells, so that the cells 310 with spacing can share the same spacer 320, which helps to reduce the number of spacers 320 and reduce the manufacturing cost of the cell stack 3.

[0036] In some embodiments, the pressure strip 4 includes a pressing part 410 and a connecting part 420 connected to each other. The pressing part 410 is positioned in the groove 210 and fits against the outer surface 202 of the cover 2. The end of the connecting part 420 is fixedly connected to the lower box 1.

[0037] In this embodiment, a pressure strip 4 is added to the groove 210 on the outer surface 202 of the cover 2 to reinforce the connection between the cover 2 and the lower housing 1. The groove 210 also engages with the protrusion 220 on the inner surface 201 of the cover 2 to transmit pressure to the spacer 320, thereby limiting and stably supporting the battery cell stack 3. Figures 1-3 and Figure 5 As shown, the pressure strip 4 may include a pressing part 410 and a connecting part 420. One end of the pressing part 410 is connected to one end of the connecting part 420. The pressing part 410 is located in the groove 210 and first adheres to the outer surface 202 of the cover 2, which can increase the force-bearing area between the pressing part 410 and the outer surface 202 of the cover 2, ensuring that the pressing part 410 can stably apply pressure towards the lower housing 1 to the cover 2, and ensuring that the cover 2 and the lower housing 1 are fully covered. Each pressure strip 4 is provided with two connecting parts 420, which are respectively connected to the two ends of the pressing part 410. The other end of each connecting part 420 is fixedly connected to the lower housing 1, which can form a stable mechanical constraint structure and improve the assembly strength and vibration resistance of the battery pack.

[0038] In some embodiments, an adhesive layer 5 is provided in the groove 210, and the pressure strip 4 is connected to the outer surface 202 of the cover 2 through the adhesive layer 5.

[0039] like Figure 3 As shown, an adhesive layer 5 is provided in the groove 210 of the outer surface 202 of the cover 2. When the pressing part 410 of the pressure strip 4 is placed inside the groove 210, the adhesive layer 5 can firmly connect the pressure strip 4 to the outer surface 202 of the cover 2, enhance the connection strength and stability between the pressure strip 4 and the outer surface 202 of the cover 2, prevent the pressure strip 4 from falling out of the groove 210, and ensure that the pressure strip 4 can provide a stable and reliable fixing effect for the cover 2.

[0040] For example, the adhesive layer 5 may be formed using an adhesive such as an insulating adhesive.

[0041] In some embodiments, the connecting portion 420 has a through hole 421 for accommodating fasteners, and the connecting portion 420 is fixedly connected to the lower housing 1 through the through hole 421 and the fasteners passing through the through hole 421.

[0042] Specifically, such as Figure 5 As shown, by providing a through hole 421 at the end of the connecting part 420 and using fasteners, it is convenient to accurately position and quickly connect the pressure strip 4 and the lower housing 1, ensuring the reliability of the assembly between the pressure strip 4 and the lower housing 1.

[0043] In addition, the cost of creating the through hole 421 is relatively low, and the fasteners, such as bolts, are readily available, which helps to reduce the assembly cost of the battery pack.

[0044] For example, fasteners can be screws.

[0045] In some embodiments, the lower housing 1 is provided with a horizontally extending flange surface 101, and the connecting portion 420 is fixed to the flange surface 101.

[0046] like Figure 1 and Figure 5 As shown, the lower housing 1 is provided with a horizontally extending flange face 101, which can provide threaded holes for fastener connection positions. In this way, the connecting part 420 of the pressure strip 4 can be fixed to the flange face 101 by fasteners, and the connecting part 420 is close to or fits against the outer surface 202 on the side of the cover 2. This helps to ensure the tightness of the pressure strip 4 and the fixing effect on the cover 2, and realizes a stable connection between the pressure strip 4 and the lower housing 1.

[0047] In addition, to enhance the connection strength between the lower housing 1 and the cover 2, the edge of the cover 2 is provided with a flange extending horizontally. The lower housing 1 can be further connected to the cover 2 through the flange face 101 and bolts to ensure the reliability of the connection between the two.

[0048] In some embodiments, the pressure strip 4 is made of a single piece of metal. Specifically, the pressure strip 4 made of a single piece of metal has higher structural strength and stability, which can enhance the fixing effect on the cover 2, while also reducing the manufacturing difficulty of the pressure strip 4, reducing the production cost of the pressure strip 4, and ensuring that the pressure strip 4 can remain sturdy and reliable during long-term use.

[0049] For example, the pressure strip 4 can be a flexible metal pressure strip 4, such as a stainless steel strip; or it can be a rigid metal pressure strip 4, such as a sheet metal pressure strip 4.

[0050] It should be noted that some embodiments of this application have been described above. Other embodiments are within the scope of the appended claims.

[0051] The various embodiments in this application are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0052] The description in this application is given for illustrative purposes and is not intended to be exhaustive or to limit the application to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical application of this application and to enable those skilled in the art to understand this application and design various embodiments with various modifications suitable for a particular purpose.

[0053] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of this application (including the claims) is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the embodiments of this application as described above, which are not provided in the details for the sake of brevity.

[0054] Although this application has been described in conjunction with specific embodiments thereof, many substitutions, modifications and variations of these embodiments will be apparent to those skilled in the art from the foregoing description.

[0055] The embodiments of this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of this application should be included within the protection scope of this application.

Claims

1. A battery pack, characterized in that, The battery includes a battery housing and a cell stack disposed within the battery housing; the battery housing includes a lower housing, a cover covering the lower housing, and a pressure strip that abuts against the outer surface of the cover; the cell stack includes a plurality of cells arranged side by side and a spacer disposed on top of the cells. The cover has a recessed groove facing the lower box body, the top of the spacer abuts against the inner surface of the cover body and corresponds to the position of the groove; the opposite ends of the pressure strip are fixedly connected to the lower box body.

2. The battery pack according to claim 1, characterized in that, The inner surface of the cover is provided with protrusions for squeezing the spacer. The protrusions protrude toward the lower box and are positioned opposite the groove. The spacer is connected to the surface of the protrusions.

3. The battery pack according to claim 2, characterized in that, The groove is provided in at least two parts, and at least one of the grooves extends along the length direction of the lower housing, and / or At least one of the grooves extends along the width direction of the lower housing.

4. The battery pack according to claim 2, characterized in that, The spacer is made of foam and is compressibly disposed between the protrusion and the battery cell.

5. The battery pack according to claim 2, characterized in that, The battery cell is a prismatic cell, and the bottom surface of the spacer is adhered to the top surface of two prismatic cells that are spaced apart from each other.

6. The battery pack according to claim 2, characterized in that, The pressure strip includes a pressing part and a connecting part that are connected to each other. The pressing part is positioned in the groove and fits against the outer surface of the cover; the end of the connecting part is fixedly connected to the lower box.

7. The battery pack according to claim 4, characterized in that, An adhesive layer is provided in the groove, and the pressure strip is connected to the outer surface of the cover through the adhesive layer.

8. The battery pack according to claim 6, characterized in that, The connecting part has a through hole for accommodating fasteners, and the connecting part is fixedly connected to the lower housing through the through hole and the fasteners passing through the through hole.

9. The battery pack according to claim 8, characterized in that, The lower housing is provided with a horizontally extending flange surface, and the connecting part is fixed to the flange surface.

10. The battery pack according to any one of claims 1-9, characterized in that, The pressure strip is made of a single piece of metal.

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