Cylindrical battery cover plate and cylindrical battery

Abstract

The cylindrical battery cover plate comprises a cover plate body, the cover plate body is made of aluminum, a connecting layer is arranged on the lower surface of the cover plate body, the connecting layer is made of stainless steel, a boss extends out of the connecting layer in the direction far away from the cover plate body, and the boss is provided with a through hole. The boss is coaxial with the cover plate body, and the diameter of the boss is smaller than that of the cover plate body. According to the utility model, the connection stability and reliability between the cover plate structure and the busbar can be realized, the overall performance of the battery pack is improved, and meanwhile, the installation efficiency of the cover plate structure and the battery shell is improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and more specifically, to a cylindrical battery cover and a cylindrical battery. Background Technology

[0002] In the assembly process of cylindrical batteries, the busbar (BUSBAR) plays a crucial role in connecting individual battery cells to achieve power transfer. However, in applications such as 4680 cylindrical batteries, the significant differences in the physical and chemical properties of these two metals, such as the battery cover being made of stainless steel while the BUSBAR is mostly made of aluminum, present numerous challenges to the welding process.

[0003] First, stainless steel and aluminum have significantly different melting points. Aluminum has a melting point of only 660°C, while stainless steel has a melting point of around 1500°C. This difference causes aluminum to melt rapidly during welding, while stainless steel remains almost solid. This inconsistent melting state makes it difficult for the two metals to form a stable metallurgical bond during welding, thus affecting the strength and reliability of the weld joint.

[0004] Secondly, aluminum easily forms a dense oxide film during welding. This oxide film not only hinders direct contact and fusion between aluminum and stainless steel, but may also lead to defects such as porosity and inclusions during welding, further reducing the quality of the welded joint.

[0005] Furthermore, aluminum and stainless steel have significantly different coefficients of linear expansion and thermal conductivity. During the welding process, uneven heating and the difference in their coefficients of linear expansion can easily lead to thermal stress in the two metals. This thermal stress can cause defects such as deformation and cracking of the weld joint, seriously affecting the overall performance and safety of the battery pack. Utility Model Content

[0006] The purpose of this utility model is to provide a cylindrical battery cover and a cylindrical battery, wherein the cylindrical battery cover can achieve connection stability and reliability with the busbar, improve the overall performance of the battery pack, and improve the installation efficiency with the battery casing.

[0007] A cylindrical battery cover and a cylindrical battery are disclosed. The cylindrical battery cover includes a cover body made of aluminum. A connecting layer made of stainless steel is provided on the lower surface of the cover body. A protrusion extends from the connecting layer in a direction away from the cover body. The protrusion is coaxial with the cover body, and the diameter of the protrusion is smaller than the diameter of the cover body.

[0008] In the above technical solution, the cover plate body is made of aluminum, the same material as the busbar (BUSBAR), making the welding process between the cover plate body and the busbar (BUSBAR) more controllable and reducing welding defects. It also helps ensure the stability and reliability of the connection between the cover plate body and the busbar, improving the overall performance of the battery pack. Furthermore, a connecting layer made of stainless steel is provided on the lower surface of the cover plate body for connecting to the battery casing. The connecting layer extends with protrusions in a direction away from the cover plate body, facilitating the installation of the cover structure onto the battery casing and improving the installation efficiency of the top cover structure. This invention achieves stable and reliable connection between the cover structure and the busbar, improves the overall performance of the battery pack, and simultaneously increases the installation efficiency of the cover structure and the battery casing.

[0009] Furthermore, the boss is provided with a first through hole, and the cover plate body is provided with a second through hole, the first through hole and the second through hole being connected.

[0010] In the above technical solution, the second through hole and the first through hole together constitute the electrical connection channel of the battery. When the terminal post or other conductive components pass through these two through holes, they can make close contact with the cover plate body and the connecting layer, ensuring good electrical conductivity.

[0011] Furthermore, the diameter of the first through hole is the same as the diameter of the second through hole.

[0012] In the above technical solution, when the diameters of the first and second through holes are the same, it can be ensured that the poles or other conductive components passing through these two through holes have a consistent contact area. This helps to achieve a more uniform current distribution and reduces the problems of increased resistance and heat generation caused by poor contact.

[0013] Furthermore, it also includes an electrode post, which passes through the first through hole and the second through hole in sequence.

[0014] In the above technical solution, the terminal post serves as a bridge between the battery cell and the external circuitry. It passes through the first and second through holes, allowing one end to connect to the battery cell's electrode, while the other end extends outside the battery for easy connection to a load or charging device.

[0015] Furthermore, the pole post is provided with several abutting parts, which abut against the side of the protrusion away from the cover plate body.

[0016] In the above technical solution, the contact portion provides additional fixation and support for the terminal post through close contact with the boss, which helps to prevent the terminal post from loosening or shifting due to vibration or mechanical stress during battery operation, thereby ensuring the stability and safety of the battery's electrical connection.

[0017] Furthermore, several of the abutting portions abut against the boss in a ring shape.

[0018] In the above technical solution, the abutment part can evenly distribute the pressure on the entire surface of the boss, avoiding the problem of local stress concentration and helping to reduce potential risks such as pole loosening or boss deformation caused by uneven pressure.

[0019] This utility model also provides a cylindrical battery, including a housing and the aforementioned cylindrical battery cover plate. The housing is made of stainless steel and has an opening. The connecting layer abuts against the end of the housing near the opening.

[0020] In the above technical solution, the connecting layer is used to ensure a tight connection between the cover plate structure and the shell, preventing electrolyte leakage and the entry of external contaminants.

[0021] Furthermore, the housing is also provided with a receiving cavity communicating with the opening, and the inner peripheral wall of the receiving cavity is provided with an annular portion, and the boss extends into the receiving cavity through the opening and abuts against the annular portion.

[0022] In the above technical solution, the contact between the boss and the annular portion ensures the accurate positioning and stable support of the cover structure on the casing. It also helps to form an effective sealing interface, preventing electrolyte leakage and external contaminants from entering the battery.

[0023] Compared with existing technologies, the advantages of this invention are as follows: the cover plate body is made of aluminum, enabling stable welding with the busbar (BUSBAR) and reducing welding defects. Simultaneously, it helps ensure the safety and reliability of the connection between the cover plate body and the busbar, improving the overall performance of the battery pack. Furthermore, a connecting layer made of stainless steel is provided on the lower surface of the cover plate body for connection with the battery casing. The connecting layer extends with protrusions in a direction away from the cover plate body, facilitating the installation of the cover structure onto the battery casing and improving the installation efficiency of the top cover structure. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the cover plate body according to an embodiment of the present utility model.

[0025] Figure 2 for Figure 1 An enlarged diagram of A in the diagram.

[0026] Figure 3 This is a schematic diagram of the assembly of the cover plate body and the pole post according to an embodiment of the present utility model.

[0027] Figure 4 This is a schematic diagram of the shell structure according to an embodiment of the present utility model.

[0028] Figure 5 for Figure 4 Enlarged diagram of B in the diagram.

[0029] Figure 6 This is an assembly diagram of the cylindrical battery according to an embodiment of the present invention.

[0030] Explanation of icon numbers

[0031] 1. Cover plate body; 101. Second through hole;

[0032] 2. Connecting layer; 201. Boss; 2011. First through hole;

[0033] 3. Pole post; 301. Contact part;

[0034] 4. Shell; 401. Opening; 402. Receiving cavity; 4021. Annular part. Detailed Implementation

[0035] The cylindrical battery cover and cylindrical battery of this utility model will be described in further detail below with reference to specific embodiments and accompanying drawings. The accompanying drawings show preferred embodiments of this utility model. However, this utility model can be implemented in many different forms and is not limited to the embodiments described herein.

[0036] Please refer to Figure 1 and Figure 2 In a preferred embodiment, the cylindrical battery cover of the present invention includes a cover body 1, which is made of aluminum. A connecting layer 2 is provided on the lower surface of the cover body 1. The connecting layer 2 is made of stainless steel. A boss 201 extends from the connecting layer 2 in a direction away from the cover body 1. The boss 201 is coaxial with the cover body 1, and the diameter of the boss 201 is smaller than the diameter of the cover body 1.

[0037] In practical applications, the aforementioned structure, because the cover body 1 is made of aluminum, the same material as the busbar (BUSBAR), makes the welding process between the cover body 1 and the busbar (BUSBAR) more controllable, reducing welding defects. Simultaneously, it helps ensure the stability and reliability of the connection between the cover body 1 and the busbar, improving the overall performance of the battery pack. Furthermore, a connecting layer 2, made of stainless steel, is provided on the lower surface of the cover body 1 for connection with the battery casing 4. The connecting layer 2 extends with a boss 201 in a direction away from the cover body 1, facilitating the installation of the cover structure onto the battery casing 4 and improving the installation efficiency of the top cover structure. This invention achieves stable and reliable connection between the cover structure and the busbar, improving the overall performance of the battery pack, while also increasing the installation efficiency of the cover structure and the battery casing 4.

[0038] Furthermore, the cover plate body 1 and the connecting layer 2 are integrally molded, which helps to avoid gaps between the cover plate body 1 and the connecting layer 2, thereby preventing electrolyte from entering the gaps and damaging the cover plate body 1, and improving the safety of the cylindrical battery. In this invention, there are various methods for integrally molding the cover plate body 1 and the connecting layer 2. For example, the connecting layer 2 can be integrally molded onto the cover plate body 1 using injection molding, compression molding, hot pressing, or integral casting. In this embodiment, the method for forming the cover plate body 1 and the connecting layer 2 into an integral molded part can be any of the above-mentioned integral molding methods.

[0039] Please refer to this again. Figure 1 The boss 201 has a first through hole 2011, and the cover plate body 1 has a second through hole 101. The first through hole 2011 and the second through hole 101 are connected. The second through hole 101 and the first through hole 2011 together form the electrical connection channel of the battery. When the terminal post 3 or other conductive components pass through these two through holes, they can make tight contact with the cover plate body 1 and the connecting layer 2, ensuring good electrical conductivity.

[0040] In this embodiment, the diameter of the first through hole 2011 is the same as the diameter of the second through hole 101. When the diameters of the first through hole 2011 and the second through hole 101 are the same, it ensures that the pole post 3 or other conductive components passing through these two through holes have a consistent contact area. This helps to achieve a more uniform current distribution and reduces problems such as increased resistance and heat generation due to poor contact. Through holes of the same diameter also simplify the manufacturing process. During processing, the same cutting tools or molds can be used to simultaneously machine the through holes on the boss 201 and the cover plate body 1, thereby improving production efficiency and reducing costs.

[0041] Please refer to Figure 3 The battery also includes a terminal post 3, which passes sequentially through the first through hole 2011 and the second through hole 101. Terminal post 3 acts as a bridge between the internal battery cell and the external circuitry. It passes through the first through hole 2011 and the second through hole 101, allowing one end to connect to the electrode of the battery cell, while the other end extends outside the battery for easy connection to a load or charging device. At the location where terminal post 3 passes through the through hole, a sealant (such as an O-ring, gasket, or sealant) is typically installed to prevent electrolyte leakage or external contaminants from entering the battery. The combined use of terminal post 3 and the sealant ensures good battery sealing performance.

[0042] It should be noted that the terminal post 3 is provided with several abutment portions 301, which abut against the side of the boss 201 away from the cover plate body 1. It can be understood that by providing the abutment portions 301 and ensuring close contact with the boss 201, the contact area between the terminal post 3 and the boss 201 is increased, which in turn increases the contact area between the terminal post 3 and the cover plate body 1. This provides additional fixation and support for the terminal post 3, helping to prevent it from loosening or shifting due to vibration or mechanical stress during battery operation, thereby ensuring the stability and safety of the battery's electrical connection.

[0043] Specifically, several abutting portions 301 are arranged in a ring to abut the boss 201. The abutting portions 301 can evenly distribute the pressure on the entire surface of the boss 201, avoiding the problem of local stress concentration and helping to reduce potential risks such as loosening of the pole post 3 or deformation of the boss caused by uneven pressure.

[0044] Please refer to Figures 4 to 6 This utility model also provides a cylindrical battery, including a housing 4 and a cylindrical battery cover plate. The housing 4 is made of stainless steel and has an opening 401. A connecting layer abuts against the end of the housing 4 near the opening 401. The connecting layer is used to ensure a tight connection between the cover plate structure and the housing, preventing electrolyte leakage and the entry of external contaminants.

[0045] Furthermore, the housing 4 also has a receiving cavity 402 communicating with the opening 401. The inner peripheral wall of the receiving cavity 402 has an annular portion 4021. The boss 201 extends into the receiving cavity 402 through the opening 401 and abuts against the annular portion 4021. The abutment between the boss 201 and the annular portion 4021 ensures the accurate positioning and stable support of the cover structure on the housing 4. It also helps to form an effective sealing interface, preventing electrolyte leakage and external contaminants from entering the battery.

[0046] In the description of this utility model, it should be understood that terms such as "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0047] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0048] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0049] Although the description of this utility model has been given in conjunction with the specific embodiments described above, it is obvious to those skilled in the art that many substitutions, modifications, and variations can be made based on the above description. Therefore, all such substitutions, modifications, and variations are included within the spirit and scope of the appended claims.

Claims

1. A cylindrical battery cover, characterized in that, The cover plate includes a cover body made of aluminum. A connecting layer made of stainless steel is provided on the lower surface of the cover plate. A boss extends from the connecting layer in a direction away from the cover plate, the boss being coaxial with the cover plate and having a diameter smaller than that of the cover plate.

2. The cylindrical battery cover plate according to claim 1, characterized in that, The boss is provided with a first through hole, and the cover plate body is provided with a second through hole, and the first through hole and the second through hole are connected.

3. The cylindrical battery cover plate according to claim 2, characterized in that, The diameter of the first through hole is the same as the diameter of the second through hole.

4. The cylindrical battery cover plate according to claim 2, characterized in that, It also includes an electrode post, which passes through the first through hole and the second through hole in sequence.

5. The cylindrical battery cover plate according to claim 4, characterized in that, The pole post is provided with several abutting parts, and the abutting parts abut against the side of the protrusion away from the cover plate body.

6. The cylindrical battery cover plate according to claim 5, characterized in that, Several of the aforementioned abutting portions abut against the aforementioned boss in a ring shape.

7. A cylindrical battery, characterized in that, The device includes a housing and a cylindrical battery cover plate as described in any one of claims 1 to 6, the housing being made of stainless steel, the housing having an opening, and the connecting layer abutting against one end of the housing near the opening.

8. The cylindrical battery according to claim 7, characterized in that, The housing also has a receiving cavity communicating with the opening. The inner peripheral wall of the receiving cavity has an annular portion. The boss extends into the receiving cavity through the opening and abuts against the annular portion.

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