A battery pack
By incorporating buffers and insulating films into the battery pack, performance issues caused by insufficient or excessive buffer space were resolved, thereby improving the stability and cycle performance of the battery pack.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CALB GROUP CO LTD
- Filing Date
- 2025-05-29
- Publication Date
- 2026-06-26
AI Technical Summary
In a battery pack, insufficient buffer space will affect the battery's cycle performance, while excessive buffer space will affect the installation stability of the battery pack.
In the battery pack, buffers are placed between adjacent batteries, and insulating films are placed between the insulating layers to increase insulation and sealing, and to prevent the buffers from affecting the buffer space.
This improves the installation stability of the battery pack and the cycle performance of the battery, avoiding performance degradation caused by insufficient or excessive buffer space.
Smart Images
Figure CN224417946U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of batteries, and in particular to a battery pack. Background Technology
[0002] A battery pack typically consists of multiple batteries arranged in a specific direction. Within a battery pack, the batteries are usually spaced apart to accommodate deformation during charge-discharge cycles and to prevent short circuits between adjacent batteries. The space between adjacent batteries serves as a buffer for battery expansion. However, since the battery's cycle performance is also affected by this buffer space, insufficient buffer space will negatively impact and degrade the battery's cycle performance. Conversely, excessive buffer space can cause the batteries within the pack to wobble, affecting the stability of the battery installation. Utility Model Content
[0003] This application discloses a battery pack that maintains installation stability while preventing cycle performance degradation due to insufficient buffer space.
[0004] To achieve the above objectives, this application provides the following technical solution:
[0005] This application provides a battery pack, which includes at least two batteries and a buffer is provided between adjacent batteries;
[0006] The battery includes a casing body and an end cap. The casing body has at least one opening, and the end cap covers the opening. An insulating layer is provided on the outer surface of the casing body, and an insulating film is provided on the outer surface of the end cap. The insulating film extends from the surface of the end cap to the outer surface of the casing body adjacent to the end cap.
[0007] The buffer is disposed between the insulating layers of adjacent batteries.
[0008] The beneficial effects of adopting the technical solution of this application are as follows:
[0009] An insulating layer is provided on the outer surface of the battery casing to achieve insulation between batteries. The end cap and casing are sealed by welding, where the sealing performance of the insulating layer is prone to deterioration. Therefore, an insulating film is provided on the surface of the end cap, extending from the end cap surface to the outer surface of the casing, thereby increasing the sealing performance between the end cap and the casing and achieving insulation. A buffer is provided between adjacent batteries within the battery pack to increase the insulation between them and improve the installation stability of the battery pack. To buffer battery expansion during charging and discharging, the buffer is placed between the insulating layers of adjacent batteries, avoiding the location of the insulating film. If the buffer were placed at the location of the insulating film between adjacent batteries, the overlapping area between the insulating film and the insulating layer would reduce the buffer space, resulting in poorer battery cycle performance. In this application, the buffer is placed at the location of the insulating layer between adjacent batteries, thus avoiding any impact on the buffer space. Attached Figure Description
[0010] Figure 1 This is a schematic diagram of the structure of a battery pack provided in an embodiment of this application;
[0011] Figure 2 This is a schematic diagram of the structure of a battery;
[0012] Figure 3 This is a side view of the structure of adjacent batteries in one embodiment.
[0013] Icon labels:
[0014] 100 - Battery pack; 10 - Battery; 20 - Buffer;
[0015] 11-Shell body; 12-End cap; 121-Pole post assembly; 13-Insulating layer; 14-Insulating film. Detailed Implementation
[0016] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0017] Figure 1 This is a schematic diagram of the structure of a battery pack according to one embodiment. Figure 1As shown, the battery pack 100 includes at least two batteries 10 arranged along a first direction, i.e., the x-direction shown in the figure. The number of batteries 10 in the battery pack 100 can be multiple, such as 3, 4, 5, 8, 10, 13, 15, or more. No specific limitation is made here; the design can be based on the electrical performance of the battery pack 100.
[0018] Figure 2 This is a schematic diagram of the structure of a battery 10. (See attached diagram.) Figure 2 As shown, the battery 10 includes a casing body 11 and end caps 12. The casing body 11 has at least one opening, and correspondingly, the number of end caps 12 can be at least one. The end caps 12 cover the opening of the casing body 11. One end cap 12 can be covered at each opening. The battery cell of the battery 10 can be disposed within the receiving space formed by the casing body 11 and the end caps 12. The battery cell may include a cell body and tabs connected to the cell body, and the tabs may be divided into positive tabs and negative tabs. The end caps 12 may be provided with terminal assembly 121, such as a positive terminal and a negative terminal. The positive terminal can be connected to the positive tab of the battery cell, and the negative terminal can be connected to the negative tab of the battery cell.
[0019] Along the height direction of the battery 10, the battery 10 includes a top surface and a bottom surface, and the end cap 12 is disposed on the top surface of the battery 10. The outer surface of the casing body 11 is provided with an insulating layer 13, such as an insulating coating formed by spraying or coating processes. The surface of the end cap 12 is provided with an insulating film 14, which can be formed on the surface of the end cap 12 by covering. To improve the insulation at the joint between the end cap 12 and the casing body 11, the insulating film 14 can extend from the surface of the end cap 12 to the outer surface of the casing body 11 adjacent to the end cap 12. The insulating layer 13 can cover the entire outer surface of the casing body 11, or it can have a certain gap from the opening of the casing body 11. After the insulating film 14 extends to the surface of the casing body 11 adjacent to the end cap 12, it abuts against the insulating layer 13, or it covers part of the insulating layer 13.
[0020] In one embodiment, the insulating film 14 covers a portion of the insulating layer 13. That is, there is a partial overlap between the insulating film 14 and the insulating layer 13. The insulating layer 13 covers the entire outer surface of the shell body 11. The portion of the insulating film 14 on the outer surface of the shell body 11 completely overlaps with the insulating layer 13 to increase the insulation of the shell body 11.
[0021] Reference Figure 2 To improve the installation stability of the battery pack 100 and to provide a certain expansion buffer space for the battery pack 100, a buffer element 20 can be set between adjacent batteries 10 in the battery pack 100.
[0022] Figure 3 This is a side view schematic diagram of adjacent batteries 10 in one embodiment. Figure 3As shown, the buffer 20 is disposed between the insulating layers 13 of the adjacent batteries 10.
[0023] Reference Figure 2 and Figure 3 An insulating layer 13 is provided on the outer surface of the casing body 11 of the battery 10 to achieve insulation between batteries 10. The end cap 12 and the casing body 11 are sealed by welding. The sealing performance of the insulating layer 13 is prone to deterioration at this point. Therefore, an insulating film 14 is provided on the surface of the end cap 12, extending from the surface of the end cap 12 to the outer surface of the casing body 11. This insulating film 14 increases the sealing performance between the end cap 12 and the casing body 11, achieving an insulation effect. A buffer member 20 is provided between adjacent batteries 10 within the battery pack 100 to increase the insulation between adjacent batteries 10 and to increase the installation stability of the battery pack 100. To buffer the expansion of the batteries 10 during charging and discharging, the buffer member 20 is positioned between the insulating layers 13 of adjacent batteries 10, avoiding the location of the insulating film 14. If the buffer element 20 is located at the position of the insulating film 14 between adjacent batteries 10, the overlapping area between the insulating film 14 and the insulating layer 13 will reduce the buffer space and worsen the cycle performance of the battery 10. In this application, the buffer element 20 is located at the position of the insulating layer 13 of the adjacent battery 10, thereby avoiding the impact on the buffer space.
[0024] Continue to refer to Figure 3 In one embodiment, along the height direction of the battery 10, i.e. along Figure 1 In the y-direction shown, on the side near the end cap 12, the distance h1 between the buffer member 20 and the insulating film 14 is 0.5-5 mm. For example, the value of h1 can be 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, or any two of the above values.
[0025] The value of the spacing h1 should not be too large. If the distance between the buffer 20 and the insulating film 14 is too large, the lack of buffering at the top of the battery 10 will increase the risk of lithium plating during charge and discharge cycles. If the value of the spacing h1 is too small, the distance between the buffer 20 and the edge of the insulating layer 13 will be too close. When the buffer 20 is deformed by compression, it will affect the connection between the insulating film 14 and the insulating layer 13. If the connection between the insulating film 14 and the insulating layer 13 fails, it will affect the insulation between batteries 10.
[0026] In one embodiment, along the height direction of the battery 10, on the side near the end cap 12, the distance h2 between the buffer member 20 and the edge of the insulating layer 13 is 1-10 mm. Exemplarily, the value of h1 can be any two values between 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 10 mm, or more.
[0027] If the spacing h2 is too large, the lack of buffering at the top of the battery 10 will increase the risk of lithium plating during charge-discharge cycles. If the spacing h2 is too small, the distance between the buffer 20 and the edge of the insulating layer 13 will be too close. When the buffer 20 is deformed by compression, it will affect the connection between the insulating film 14 and the insulating layer 13. If the connection between the insulating film 14 and the insulating layer 13 fails, it will affect the insulation between batteries 10.
[0028] In one embodiment, along the height direction of the battery 10, on the side near the end cap 12, the distance h3 between the buffer member 20 and the surface of the end cap 12 facing away from the housing body 11 is 3-10 mm. Figure 3 Taking the direction shown as an example, h3 is also the distance between the buffer 20 and the upper surface of the end cap 12. For example, the value of h3 can be any two values between 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 10mm or more.
[0029] If the spacing h3 is too large, the lack of buffering at the top of the battery 10 will increase the risk of lithium plating during charge-discharge cycles. If the spacing h3 is too small, the distance between the buffer 20 and the upper surface of the end cap 12 will be too close. Since the insulating film 14 extends from the upper surface of the end cap 12 to the shell body 11, when the buffer 20 is deformed by compression, it will affect the connection between the insulating film 14 and the insulating layer 13. If the connection between the insulating film 14 and the insulating layer 13 fails, it will affect the insulation between the batteries 10.
[0030] In one embodiment, the distance h4 between the buffer member 20 and the center of the battery 10 along its height direction is 10-150 mm. Exemplarily, the value of h4 can be any two values between 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, 60 mm, 70 mm, 80 mm, 90 mm, 100 mm, 110 mm, 120 mm, 130 mm, 140 mm, and 150 mm.
[0031] Among them, the value of h4 is relatively large, the buffer 20 is far from the center of the battery 10, and the expansion of the central area of the battery 10 is large. Therefore, the contact probability of adjacent batteries 10 when expansion occurs can be increased, thereby affecting the safety of the battery 10.
[0032] In one embodiment, the buffer 20 includes a plurality of buffer strips, at least some of which are located on the side of the adjacent battery 10 near the top surface along the height direction of the battery 10, and / or at least some of which are located on the side of the adjacent battery 10 near the bottom surface.
[0033] The buffer strip can prevent adjacent batteries 10 from squeezing each other, and can also leave a certain buffer space between adjacent buffer strips to take advantage of the deformation that occurs during the charging and discharging process of the battery 10.
[0034] In one embodiment, the distance h5 between the buffer strip on the side closest to the bottom surface of the battery 10 and the bottom surface is 0.5-5mm. For example, the value of h5 can be 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, or any two of the above values.
[0035] If the distance between the buffer strip 20 and the bottom surface is too close, it will affect the installation of the battery pack. If the distance between the buffer strip 20 and the bottom surface is too far, it will affect the buffering effect of the buffer strip.
[0036] In one embodiment, the buffer member 20 is a one-piece frame structure. The frame structure may include multiple interconnected buffer strips. The one-piece frame structure of the buffer member 20 facilitates its installation and fixation.
[0037] In one embodiment, the thickness H of the buffer 20 is 1-5 mm, wherein the thickness direction of the buffer 20 is the arrangement direction of adjacent batteries 10. Exemplarily, the thickness of the buffer 20 can be, for example, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, or any two of these values.
[0038] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of this application. Therefore, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application also intends to include these modifications and variations.
Claims
1. A battery pack, characterized in that, It includes at least two batteries arranged along a first direction, with a buffer between adjacent batteries; The battery includes a casing body and an end cap. The casing body has at least one opening, and the end cap covers the opening. An insulating layer is provided on the outer surface of the casing body, and an insulating film is provided on the outer surface of the end cap. The insulating film extends from the surface of the end cap to the outer surface of the casing body adjacent to the end cap. The buffer is disposed between the insulating layers of adjacent batteries.
2. The battery pack according to claim 1, characterized in that, Along the height direction of the battery, on the side near the end cap, the distance h1 between the buffer and the insulating film is 0.5-5mm.
3. The battery pack according to claim 1, characterized in that, Along the height direction of the battery, on the side near the end cap, the distance h2 between the buffer and the edge of the insulating layer is 1-10 mm.
4. The battery pack according to claim 1, characterized in that, Along the height direction of the battery, on the side near the end cap, the distance h3 between the buffer and the surface of the end cap facing away from the main body of the casing is 3-10 mm.
5. The battery pack according to claim 1, characterized in that, Along the height direction of the battery, the distance h4 between the buffer and the center of the battery in the height direction is 10-150mm.
6. The battery pack according to claim 1, characterized in that, The insulating film covers a portion of the insulating layer.
7. The battery pack according to any one of claims 1-6, characterized in that, Along the height direction of the battery, the battery includes a top surface and a bottom surface, and the end cap is disposed on the top surface of the battery; The buffer includes a plurality of buffer strips, with at least some of the buffer strips located on the side of the adjacent battery near the top surface along the height direction of the battery, and / or at least some of the buffer strips located on the side of the adjacent battery near the bottom surface.
8. The battery pack according to claim 7, characterized in that, The distance h5 between the buffer strip on the side closest to the bottom surface of the battery and the bottom surface is 0.5-5mm.
9. The battery pack according to claim 7, characterized in that, The buffer is a one-piece frame structure, which includes multiple interconnected buffer strips.
10. The battery pack according to any one of claims 1-6, characterized in that, The thickness H of the buffer is 1-5 mm, wherein the thickness direction of the buffer is the first direction.