Battery and battery pack

Abstract

The application relates to the field of batteries and battery packs. The battery comprises a shell, a battery cell arranged in the shell, and a cover plate assembly arranged at an opening of the shell; the cover plate assembly comprises a cover plate body and a pole post, and a tab of the battery cell is electrically connected to the pole post; the cover plate body is provided with a pole post hole; the pole post is arranged in the pole post hole and connected to the cover plate body; the pole post is provided with a first surface, the first surface is used for electrical connection with a bus bar, the area of the first surface is s, the vertical distance between the first surface and the outer surface of the cover plate body is h, and s / h satisfies 5-500. The size of the pole post is controlled to effectively balance the heat generation and the connection strength of the pole post.

Description

Technical Field

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

[0002] A battery typically consists of a casing, a cell, and a cover assembly. The casing may have an opening, the cell is housed within a cavity in the casing, and the cover assembly closes onto the opening. The cover assembly contains terminals, to which the cell's tabs are electrically connected, thus enabling the connection between the cell and the busbar.

[0003] Since the size of the terminal block affects the connection strength between the terminal block and the cover plate, as well as the current carrying capacity of the terminal block itself, controlling the size of the terminal block to balance the connection strength between the terminal block and the cover plate and the current carrying capacity of the terminal block itself has become a challenge in battery design. Utility Model Content

[0004] This application discloses a battery and a battery pack for achieving an effective balance between heat generation and connection strength of the terminals by controlling the size of the terminals.

[0005] To achieve the above objectives, this application provides the following technical solution:

[0006] In a first aspect, this application provides a battery, which includes: a housing, a battery cell disposed within the housing, and a cover plate assembly disposed at an opening in the housing; the cover plate assembly includes a cover plate body and a terminal post, wherein the battery cell's electrode tab is electrically connected to the terminal post; the cover plate body has a terminal post hole; the terminal post is disposed in the terminal post hole and connected to the cover plate body.

[0007] The electrode post has a first surface for electrical connection with the busbar. The area of ​​the first surface is s, and the vertical distance between the first surface and the outer surface of the cover plate body is h. The ratio of s / h is 5 to 500, and the unit of s is mm. 2 The unit of h is mm. The outer surface of the cover plate body is the side facing the busbar.

[0008] The battery of this application, by controlling the ratio of s to h, can improve the connection strength between the cover plate body and the terminal in the cover plate assembly without affecting the current-carrying effect of the terminal. Since the first surface of the terminal is connected to the busbar, a larger area s of the first surface results in a larger current-carrying area for the terminal, reducing heat generation and increasing the reliability of the connection with the busbar. At this point, controlling the vertical distance h between the first surface and the outer surface of the cover plate body (i.e., the height of the terminal beyond the cover plate body) within the aforementioned ratio range satisfies the connection strength requirements between the terminal and the cover plate body. Therefore, the cover plate assembly of this application, by controlling the s to h ratio to be between 5 and 500, can ensure both the connection strength requirements of the cover plate assembly and the current-carrying effect of the terminal, while reducing heat generation. If the s / h value is too large, it indicates that the difference between s and h is too large, the size of h is too small, the connection strength between the terminal and the cover plate body is low, and it is prone to connection failure. If the s / h value is too small, the h value will be relatively high, which will easily increase the resistance of the terminal, reduce the overcurrent effect of the terminal, and increase the heat generation of the terminal.

[0009] Secondly, this application provides a battery pack, the battery module including at least two batteries of this application.

[0010] The battery module of this application, since it contains the battery of this application, has the same advantages as the battery of this application, which has high reliability of cover assembly connection and good overcurrent effect. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of a battery according to one embodiment of this application;

[0012] Figure 2 This is a schematic cross-sectional view of the battery at the cover plate assembly according to one embodiment;

[0013] Figure 3 This is a structural schematic diagram of a cover plate assembly;

[0014] Figure 4 This is a schematic diagram showing the relative position structure of the pole post and the cover plate body in one embodiment;

[0015] Figure 5 This is a schematic diagram of the cover plate assembly according to another embodiment of this application;

[0016] Figure 6 This is a schematic diagram of the structure of a cover plate assembly according to one embodiment.

[0017] Icon labels:

[0018] 1-Battery; 10-Casing; 20-Cell; 21-Taper; 22-Cell Body; 23-Adapter Plate;

[0019] 30 - Cover plate assembly; 31 - Cover plate body; 311 - Outer surface; 312 - Inner surface; 32 - Pole post hole;

[0020] 33-Pole post; 331-First surface; 332-Second surface; 333-First flange; 334-Second flange;

[0021] 40 - Insulating component; 41 - First insulating part; 42 - Second insulating part; 43 - Third insulating part. Detailed Implementation

[0022] 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.

[0023] Figure 1 This is a schematic diagram of the structure of a battery according to one embodiment of this application. Figure 1 As shown, the battery includes a casing 10, a battery cell (not shown), and a cover assembly 30. The casing 10 has an opening, and the battery cell is disposed within the receiving space of the casing 10. The cover assembly 30 closes onto the opening of the casing 10.

[0024] Figure 2 This is a schematic cross-sectional view of the battery at the cover assembly according to one embodiment. Figure 2 As shown, the battery cell 20 may include a battery cell body 22 and a tab 21 connected to the battery cell body 22.

[0025] In one embodiment, the battery cell body may include a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive and negative electrode sheets, all stacked together. The positive electrode sheet includes a positive current collector and a positive electrode material layer disposed on the surface of the positive current collector. The negative electrode sheet includes a negative current collector and a negative electrode material layer disposed on the surface of the negative current collector. The battery cell body has tabs including a positive tab and a negative tab. The positive tab can be led out from the positive current collector, and the negative tab can be led out from the negative current collector.

[0026] Figure 3 This is a schematic diagram of a cover plate assembly. The cover plate assembly 30 may include a cover plate body 31 and a pole post 33 connected to the cover plate body 31. Figure 4 This is a schematic diagram illustrating the relative position structure of the pole post and the cover plate body according to one embodiment. See also... Figure 3 and Figure 4 The cover plate body 31 is provided with a pole post hole 32. A pole post 33 is disposed in the pole post hole 32 and connected to the cover plate body 31. See also... Figure 2The tab 21 of the battery cell 20 is electrically connected to the terminal 33. The tab can be directly connected to the terminal, or an electrical connection can be achieved through an adapter. Figure 2 In the illustrated embodiment, the tab 21 is electrically connected to the post 33 via an adapter piece 23. The adapter piece can be a metal sheet, such as a copper sheet.

[0027] The terminal post 33 has a first surface 331, which is used for electrical connection with the busbar. The area of ​​the first surface 331 is s, and the vertical distance between the first surface 331 and the outer surface 311 of the cover plate body 31 is h. The ratio of s / h is 5 to 500, and the unit of s is mm. 2 The unit of h is mm. The vertical distance h between the first surface 331 and the outer surface 311 of the cover plate body 31 is the protrusion height of the pole post 33 from the outer surface 311 of the cover plate body 31.

[0028] For example, s / h can be any two values ​​between 5, 10, 15, 20, 30, 50, 80, 100, 120, 150, 170, 200, 250, 280, 300, 320, 350, 380, 400, 420, 450, 480, or 500 or more.

[0029] The cover plate assembly of this application improves the connection strength between the cover plate body and the electrode post without affecting the current flow effect of the electrode post by controlling the ratio of s to h. Since the first surface of the electrode post is connected to the busbar, a larger area s of the first surface results in a larger current flow area for the electrode post, reducing heat generation and increasing the reliability of the connection with the busbar. When the vertical distance h between the first surface and the outer surface of the cover plate body (i.e., the height of the electrode post exceeding the cover plate body) is controlled within the aforementioned ratio range, the connection strength requirement between the electrode post and the cover plate body can be met. Therefore, the cover plate assembly of this application, by controlling the ratio of s to h to be between 5 and 500, can ensure both the connection strength requirement of the cover plate assembly and the current flow effect of the electrode post, while reducing heat generation. If the s / h value is too large, it indicates a large difference between s and h, a small h value, and a low connection strength between the electrode post and the cover plate body, which can easily lead to connection failure. If the s / h value is too small, the h value will be relatively high, which will easily increase the resistance of the terminal, reduce the overcurrent effect of the terminal, and increase the heat generation of the terminal.

[0030] Continue to refer to Figure 4 In one embodiment, the area s of the first surface 331 is larger than the area of ​​the pole hole 32. The larger area s of the first surface 331 allows the pole 33 to have better flow performance and reduces heat generation after the pole 33 is connected to the busbar.

[0031] The shape of the first surface 331 can be racetrack-shaped, circular, square, or other shapes. This application does not impose excessive limitations on the shape of the first surface 331. When the first surface 331 is racetrack-shaped, the ratio of its length to its width satisfies a value between 1.4 and 1.7. For example, the ratio of the length to the width of the first surface 331 can be, for example, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, or 1.7 or any two values ​​above. If the ratio of the length to the width of the first surface 331 is too large, it indicates that the length of the pole hole 32 is also too long, which will reduce the torsional resistance of the cover body 31 and easily cause deformation of the cover body.

[0032] When the first surface 331 is circular, its diameter can be, for example, 6mm to 55mm. When the first surface 331 is square, its side length is 6mm to 50mm.

[0033] Among them, continue to refer to Figure 4 The terminal post 33 also includes a second surface 332, which is used for electrical connection with the battery cell. The second surface 332 is located on the other side of the terminal post 33 opposite to the first surface 331. In the battery, the second surface 332 of the terminal post 33 faces the battery cell. The tabs of the battery cell are electrically connected to the second surface 332 of the terminal post 32. The tabs and the second surface 332 of the terminal post 32 can be directly electrically connected, or they can be electrically connected through an adapter plate; the specific connection method is not limited here.

[0034] like Figure 4 As shown, in one embodiment, the second surface 332 is located within the electrode post hole 32. This structural arrangement saves space in the battery's height and increases the battery's energy density.

[0035] Figure 5 This is a schematic diagram of the cover plate assembly according to another embodiment of this application. Figure 5 As shown, in another embodiment, the second surface 332 protrudes outward from the electrode hole 32, that is, it protrudes from the inner surface 312 of the cover plate body 31. On the side facing the battery cell, the second surface 332 protrudes from the inner surface of the cover plate body 31, that is, the second surface 332 is located outside the electrode hole 32. The inner surface of the cover plate body is the surface of the cover plate body facing the battery cell. In this structural arrangement, the connection strength between the electrode 33 and the battery cell is higher, facilitating the connection between the two.

[0036] In one embodiment, the area s of the first surface ranges from 25 mm. 2 ~3000mm 2 The value of h ranges from 0.5mm to 7mm, or for example, from 2mm to 4mm. The area s of the first surface is 25mm². 2 ~3000mm2 This ensures a high connection strength between the electrode and the busbar, while also providing the electrode with high current-carrying capacity and reducing heat generation. When the protrusion height h of the electrode from the outer surface of the cover plate body is within the range of 0.5mm to 7mm, it ensures a high connection strength between the electrode and the cover plate body, while also providing high current-carrying capacity and reducing heat generation.

[0037] For example, the value of s can be 25mm. 2 50mm 2 100mm 2 200mm 2 500mm 2 800mm 2 1000mm 2 1200mm 2 1500mm 2 1800mm 2 2000mm 2 2200mm 2 2500mm 2 2700mm 2 3000mm 2 Or the value between any two of the above values.

[0038] For example, the value of h can be any two values ​​between 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, or 7mm or more.

[0039] In one embodiment, refer to Figures and Figure 5 The ratio h / H to the height H of the electrode post satisfies 0.1 to 0.5. In one embodiment, the value of H ranges from 5 to 20 mm. If the h / H ratio is too low, h is too small, or H is too high, the connection strength between the electrode post and the cover plate assembly cannot be guaranteed if h is too small, and the current-carrying performance of the electrode post will be reduced if H is too large, increasing the heat generation of the electrode post. If the h / H ratio is too high, h is relatively large, or H is relatively small, the current-carrying capacity of the electrode post is low if h is large, and the strength of the electrode post cannot be guaranteed if H is small, which can easily cause deformation of the electrode post after connection with the busbar.

[0040] For example, the ratio of h / H can be any value between two values, such as 0.1, 0.2, 0.3, 0.4, or 0.5 or above.

[0041] In one embodiment, reference continues... Figure 4 and Figure 5The outer peripheral surface of the pole post 33 is provided with a first flange 333, which is insulated from the outer surface 311 of the cover plate body 31. The first flange 333 protrudes outward from the outer peripheral surface of the pole post 32 and is disposed on one side of the outer surface 311 of the cover plate body 31. By providing the first flange 333, the first flange 333 can be placed on the outer surface 311 of the cover plate body 31, increasing the contact area with the cover plate body 31 and improving the connection strength between the two. The radial dimension of the outer edge of the first flange is larger than the radial dimension of the first surface.

[0042] The ratio h1 of the height of the first flange 333 to the protrusion height h of the pole post from the outer surface 311 of the cover plate body 31, h1 / h, satisfies 0.2 to 0.8. The height direction of the first flange is the same as the height direction of the pole post, that is, along the axial direction of the pole post.

[0043] For example, h1 / h can be a value between any two values, such as 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8 or above.

[0044] Since the terminal post needs to be conductive, it can be made of metal, such as copper. To ensure high strength, the cover plate can be made of metal, such as stainless steel or an alloy. To prevent short circuits, insulation must be provided between the terminal post and the cover plate. Figure 6 This is a schematic diagram of the cover plate assembly according to one embodiment. In one embodiment, an insulating member 40 is provided between the pole post and the cover plate body.

[0045] like Figure 6 As shown, in one embodiment, the insulating member 40 includes a first insulating portion 41, a second insulating portion 42, and an optional third insulating portion 43. The first insulating portion 41 is disposed within the electrode post hole, located between the peripheral side surface of the electrode post 33 and the hole wall. The second insulating portion 42 is disposed along the axial direction of the electrode post 33 between the electrode post 33 and the outer surface 311 of the cover plate body 31. The third insulating portion 43 is disposed on the peripheral side surface of the first flange 333 of the electrode post 33.

[0046] The insulating component can be a rubber pad or other insulating polymer pad.

[0047] It is understandable that the insulating component can be a separate insulating pad, or it can be an insulating layer located on the inner wall of the electrode hole, or an insulating layer located on the surface of the electrode.

[0048] In one embodiment, the first insulating part, the second insulating part, and the optional third insulating part can be an integrally connected structure or a separate structure.

[0049] In one embodiment, reference is made to... Figure 5The bottom of the pole post 33 is provided with a second flange 334, which protrudes outward from the side of the pole post 33. Among them, with Figure 5 Taking the orientation shown as an example, the lower surface of the second flange 334 is coplanar with the second surface of the pole post 33. The radial dimension of the second flange 334 coincides with the dimension of the cover plate body by 2 to 10 mm.

[0050] Based on the same technical objective, embodiments of this application provide a battery module comprising at least two batteries as described in this application. Additionally, a busbar may be included. The battery terminals are connected to the busbar, such as by welding or pressing. In the battery module of this application, the batteries can be arranged in a certain direction and connected in series or parallel via the busbar.

[0051] 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, characterized in that, include: A housing, a battery cell disposed within the housing, and a cover plate assembly disposed at an opening in the housing; The cover plate assembly includes a cover plate body and an electrode post, and the electrode tab of the battery cell is electrically connected to the electrode post; The cover plate body is provided with pole hole; the pole is disposed in the pole hole and connected to the cover plate body; The electrode post has a first surface for electrical connection with the busbar. The area of ​​the first surface is s, and the vertical distance between the first surface and the outer surface of the cover plate body is h. The ratio of s / h satisfies 5 to 500, and the unit of s is mm. 2 The unit of h is mm; The outer surface of the cover plate body is a side surface that faces the busbar.

2. The battery according to claim 1, characterized in that, The value of s is in the range of 25mm. 2 ~3000mm 2 The value of h ranges from 0.5 mm to 7 mm.

3. The battery according to claim 1, characterized in that, The ratio h / H of h to the height H of the pole post satisfies 0.1 to 0.5, and the value of H ranges from 5 to 20 mm.

4. The battery according to any one of claims 1-3, characterized in that, The electrode post also includes a second surface, which is electrically connected to the electrode tab; the second surface is located inside the electrode post hole.

5. The battery according to any one of claims 1-3, characterized in that, The electrode post also includes a second surface, which is electrically connected to the electrode tab. On the side facing the battery cell, the second surface protrudes from the inner surface of the cover plate body.

6. The battery according to any one of claims 1-3, characterized in that, The outer peripheral surface of the pole post is provided with a first flange, which is insulated from the outer surface of the cover plate body.

7. The battery according to claim 6, characterized in that, The ratio of the height h1 of the first flange to h, h1 / h, satisfies 0.2 to 0.

8.

8. The battery according to any one of claims 1-3, characterized in that, The area s of the first surface is greater than the area of ​​the pole hole.

9. The battery according to any one of claims 1-3, characterized in that, The shape of the first surface is racetrack-shaped, circular, or square.

10. The battery according to claim 9, characterized in that, The first surface is in the shape of a racetrack, and the ratio of the length of the first surface to the width of the first surface satisfies 1.4 to 1.

7.

11. The battery according to any one of claims 1-3, characterized in that, An insulating element is provided between the pole and the cover plate body.

12. The battery according to claim 11, characterized in that, The insulating component includes a first insulating portion, a second insulating portion, and an optional third insulating portion; The first insulating part is disposed inside the electrode hole, located between the peripheral side of the electrode and the hole wall of the electrode hole; The second insulating part is disposed along the axial direction of the pole post between the outer surface of the pole post and the cover plate body; The third insulating part is disposed on the peripheral side of the first flange of the pole post, and the first flange of the pole post is disposed on one side of the outer surface of the cover plate body.

13. The battery according to claim 12, characterized in that, The first insulating part, the second insulating part, and the optional third insulating part are integrally connected.

14. The battery according to any one of claims 1-3, characterized in that, An adapter plate is provided between the electrode tab and the electrode post, and the electrode tab and the electrode post are electrically connected through the adapter plate.

15. A battery pack, characterized in that, It includes at least two batteries as described in any one of claims 1-14.

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