Square battery cover plate structure

Abstract

The invention provides a square battery cover plate structure, and belongs to the technical field of batteries, and the square battery cover plate structure comprises a cover plate which is provided with two through holes in a penetrating manner; the pole is arranged in the through hole, is used for being connected with an external circuit and is of a boss-shaped structure; the sealing ring is positioned in the through hole and is used for supporting the bottom of the post terminal; the upper plastic is arranged on the outer side of the pole in an annular structure and abuts against and positions the bottom of the pole, and the horizontal line of the upper surface of the upper plastic is lower than that of the upper surface of the pole; the terminal post is of the boss-shaped structure, that is, the top end of the terminal post can be inserted into the corresponding groove in the connecting piece, so that the position deviation between the terminal post and the connecting piece during welding can be avoided, and the welding quality of the terminal post and the connecting piece is indirectly improved.

Description

Technical Field

[0001] This invention application relates to the technical field of battery devices, and particularly to a square battery cover plate structure. Background Art

[0002] Currently, laser welding of square battery cover plate structures mainly uses top welding and side welding processes. The top welding process is to weld on one surface at the top of the battery. It has relatively low requirements for the integration of welding equipment and is simple in mass production. However, due to possible spatter during the welding process, it has very high requirements for the shell insertion and positioning of the previous process. The side welding process is to weld on the side of the battery. It has less impact on the inside of the battery cell, and the spatter will not easily enter the inside of the shell cover. However, protrusions may occur during the welding process, affecting subsequent assembly.

[0003] With the development of the lithium battery manufacturing industry, the laser welding process technology and its equipment technology for top cover sealing are also constantly advancing. According to the welding speed performance of the equipment, the top cover laser welding equipment and process are roughly divided into three eras: the 1.0 era (2015 - 2017) with a welding speed < 100mm / s, the 2.0 era (2017 - 2018) with a welding speed of 100 - 200mm / s, and the 3.0 era (2019 - ) with a welding speed of 200 - 300mm / s. In the 1.0 era, the equipment solution usually uses a 1kw fiber laser to emit through an ordinary laser welding head, and the welding head is driven by a servo platform motor or a linear motor to move and perform welding, with a welding speed of 50 - 100mm / s. Although the production efficiency is not high, the equipment structure is relatively simple, the stability is good, and the equipment cost is low. However, with the increase in welding speed, new problems have emerged during the welding process, such as protrusions on the weld surface, internal pores, explosion of the welding arc, etc. These problems are mainly due to the high reflectivity of aluminum alloy to laser and its good thermal conductivity.

[0004] In the existing technical solutions, the common problem is the lack of precise positioning during the welding process, which easily leads to deviation in the relative position between the pole column and the connecting piece. This deviation causes uneven local heating of the pole column during welding, with heat concentrated in certain parts, thereby causing the PPS (polyphenylene sulfide, heat-resistant up to about 280 degrees) material around the pole column to sol at a higher temperature. The PPS sol will damage the sealing performance of the battery, making the electrolyte inside the battery easily leak. This will not only reduce the capacity and performance of the battery, but may also corrode the surrounding electronic components and battery structure parts.

[0005] Content of the Invention Application

[0006] In view of this, the present invention application provides a square battery cover plate structure. In the present invention application, the pole post is in a boss-like structure, that is, the top end of the pole post can be inserted into the corresponding groove on the connecting piece, so as to avoid the deviation of the position during the welding between the pole post and the connecting piece, and indirectly improve the welding quality between the pole post and the connecting piece.

[0007] To solve the above technical problems, the present invention application provides a square battery cover plate structure, including a cover plate, on which two through holes are provided, and the two through holes are respectively used for placing the positive pole post or the negative pole post.

[0008] The pole post is placed in the through hole for connecting with an external circuit. The pole post is in a boss-like structure, and a groove adapted to the boss structure of the pole post is provided on the connecting piece.

[0009] The sealing ring is located in the through hole to provide support for the bottom of the pole post and prevent the bottom of the pole post from contacting the cover plate.

[0010] The upper plastic is in an annular structure and is placed outside the pole post to abut and position the bottom of the pole post. And the horizontal line of the upper surface of the upper plastic is lower than the horizontal line of the upper surface of the pole post. The upper plastic can provide electrical insulation for the side wall of the electrode post.

[0011] A snap ring is provided on the top of the cover plate corresponding to the through hole. The snap ring and the through hole are on the same axis. The sealing ring and the pole post are both located inside the snap ring. And the horizontal line of the upper surface of the pole post is higher than the horizontal line of the upper surface of the snap ring. The cross section of the upper plastic is in a return shape to wrap the snap ring, that is, the upper plastic can also play a protective role.

[0012] A support ring is also sleeved outside the pole post. The support ring is located above the bottom layer of the pole post to fix the position of the pole post inside the snap ring. And the upper plastic can wrap the support ring. The support ring can prevent the outer surface of the pole post from contacting the inner surface of the snap ring.

[0013] The pole post is in a three-stage boss structure, and the cross-sectional area of the pole post gradually becomes smaller from bottom to top.

[0014] An insulating sheet is also provided between the support ring and the bottom layer of the pole post. The insulating sheet is located at the bottom of the upper plastic. The insulating sheet is used to isolate the pole post from the cover plate, so as to form electrical insulation between the side of the pole post and the inner wall of the top ring.

[0015] The cover plate is made of two sections, a top cover sheet and a lower plastic. The top cover sheet is located above the lower plastic. The through hole is provided through the top cover sheet. The lower plastic is provided with a connection hole corresponding to the through hole. A top ring is provided above the lower plastic corresponding to the connection hole. The bottom of the pole post is located on the top of the top ring. And a clearance groove is formed between the outer side wall of the top ring and the inner side wall of the through hole. The sealing ring is placed in the clearance groove.

[0016] The top cover sheet and the lower plastic are detachably connected together. The top cover sheet and the lower plastic are bonded together.

[0017] An explosion-proof valve is provided on the top of the top cover sheet, which can prevent the battery from exploding.

[0018] An explosion-proof valve protection sheet is provided at the bottom of the top cover sheet, and the explosion-proof valve protection sheet ensures that the explosion-proof valve can be opened normally and the internal pressure is released in time.

[0019] A storage compartment is arranged on the lower plastic, and an explosion-proof valve protection sheet is located in the storage compartment.

[0020] In summary, compared with the prior art, the present application includes at least one of the following beneficial technical effects:

[0021] 1. Improve welding quality and optimize electrical connections:

[0022] Pole boss design: The pole adopts a boss-like structure, which can be accurately inserted into the groove of the connecting piece, effectively avoiding the position deviation between the pole and the connecting piece during welding. This design not only improves the welding quality, but also ensures the smooth conduction of current and enhances the stability of electrical connection.

[0023] Laser welding process: With the development of laser welding technology, the welding speed and accuracy have been significantly improved. The present invention adopts advanced laser welding technology to ensure efficient and accurate welding between the cover plate and the shell, further improving the overall sealing and stability of the battery.

[0024] 2. Enhance electrical insulation to prevent short circuit risks:

[0025] Upper plastic and insulating sheet: The upper plastic with a ring structure is set on the outside of the pole to prevent the bottom of the pole from being in contact and positioning, and at the same time play the role of electrical insulation. In addition, an insulating sheet is also set between the support ring and the bottom of the pole to further isolate the pole from the cover plate, effectively preventing the risk of short circuit caused by direct contact between the pole and the cover plate.

[0026] Sealing ring: A sealing ring is set in the perforation to provide support for the bottom of the pole, while enhancing the sealing of the battery, preventing electrolyte leakage and external impurities from invading, thereby improving the safety and service life of the battery.

[0027] 3. Improve safety and reliability to ensure stable battery operation:

[0028] Safety mechanism design: There is an explosion-proof valve on the top of the cover. When the internal pressure of the battery rises abnormally, the explosion-proof valve can open quickly to release the internal pressure and prevent the battery from exploding or catching fire. In addition, a support ring is also set on the outside of the pole to fix the position of the pole to prevent loosening or damage caused by vibration or impact, further improving the safety of the battery.

[0029] Explosion-proof valve protection piece and storage bin: An explosion-proof valve protection piece is provided at the bottom of the top cover piece to ensure the normal opening of the explosion-proof valve. At the same time, a storage bin is provided on the lower plastic to accommodate the explosion-proof valve protection piece, ensuring its stability and reliability. This design can provide more comprehensive protection in case of battery abnormalities, preventing mis-triggering or damage.

[0030] 4. Adapt to a wide range of application fields and meet market demands:

[0031] Wide range of application fields: The square battery cover structure is applicable to application fields such as electric vehicles, energy storage systems, and mobile devices. With the rapid development of the new energy industry, the requirements for battery performance, safety, and reliability in these fields are getting higher and higher. Through a series of innovative designs, the present invention meets the market demands and has broad market prospects.

[0032] Policy support and market development: The government supports the development of the new energy vehicle and power battery industry chain, further promoting the market application of the square battery cover structure. At the same time, with the progress of technology and the change of market demands, the square battery cover structure has advantages in aspects such as lightweight, high energy density, and high safety, meeting the technological development trend. Description of the drawings

[0033] Figure 1 It is a schematic structural diagram of a square battery cover structure of the present invention application;

[0034] Figure 2 It is a schematic structural diagram of a cross-sectional view of the present invention application;

[0035] Figure 3 For the present invention application Figure 2 The schematic structural diagram at position A in;

[0036] Figure 4 It is a schematic structural diagram of an explosion view of the cover of the present invention application.

[0037] Explanation of reference numerals:

[0038] 1. Cover; 2. Top cover piece; 3. Perforation; 4. Snap ring; 5. Lower plastic; 6. Connection hole; 7. Top ring; 8. Relief groove; 9. Sealing ring; 10. Terminal post; 11. Upper plastic; 12. Support ring; 13. Insulating sheet; 14. Explosion-proof valve; 15. Explosion-proof valve protection piece; 16. Storage bin. Detailed implementation manners

[0039] To make the objectives, technical solutions, and advantages of the embodiments of the present invention application clearer, the following will combine the attachments of the embodiments of the present invention application Figures 1-4, the technical solutions of the embodiments of the present invention application are described clearly and completely. Obviously, the described embodiments are part of the embodiments of the present invention application, rather than all of them. Based on the described embodiments of the present invention application, all other embodiments obtained by those of ordinary skill in the art belong to the scope protected by the present invention application.

[0040] This embodiment discloses a structure of a square battery cover plate 1, as shown in Figure 1 , 2 , 3, and 4: It includes a cover plate 1, through which two through holes 3 are provided. The positive electrode post 10 and the negative electrode post 10 are respectively placed in the two through holes 3. A rubber ring is placed in each through hole 3, and the rubber ring is located at the bottom of the electrode post 10 to provide support for the electrode post 10.

[0041] Both the positive electrode post 10 and the negative electrode post 10 are of a three-stage boss-like structure, and the cross-sectional area of the electrode post 10 gradually decreases from bottom to top. And a groove is provided on the connecting piece corresponding to the end of the electrode post 10. Thus, when welding the battery cover plate 1 and the connecting piece, directly inserting the electrode post 10 into the groove can prevent the position deviation of the electrode post 10 during the welding with the connecting piece.

[0042] On the upper surface of the cover plate 1, a snap ring 4 is also provided corresponding to the through hole 3. The snap ring 4 and the through hole 3 are on the same axis, and the inner diameter of the snap ring 4 is the same as the diameter of the through hole 3. The horizontal line on the upper surface of the snap ring 4 is lower than the horizontal line at the top of the middle layer of the electrode post 10. And a support ring 12 is also provided inside the snap ring 4. The support ring 12 is located outside the middle layer of the electrode post 10, and the upper surface of the support ring 12 is on the same horizontal line as the upper surface of the snap ring 4. The support ring 12 can prevent the side wall of the electrode post 10 from contacting the snap ring 4, thereby indirectly limiting the position of the electrode post 10.

[0043] Furthermore, an insulating sheet 13 is also provided inside the snap ring 4. The insulating sheet 13 is located on the upper surface of the bottom layer of the electrode post 10. The inner diameter of the insulating sheet 13 abuts against the outer wall of the middle layer of the electrode post 10, and the outer wall of the insulating sheet 13 abuts against the inner wall surface of the snap ring 4. Thus, it can be further used to fix the position of the electrode post 10, effectively preventing the indirect contact between the electrode post 10 and the cover plate 1 to form a short circuit.

[0044] Specifically, an upper plastic 11 is also provided corresponding to the electrode post 10 and the snap ring 4. The upper plastic 11 is annular and is located between the snap ring 4 and the electrode post 10, and it covers the snap ring 4, that is, the upper plastic 11 can fill the cavity between the electrode post 10 and the snap ring 4, thereby further providing electrical insulation for the electrode post 10.

[0045] The upper plastic 11 is fixed on the outside of the electrode post 10 by injection molding, and forms a tightly wrapped layer with a square cross-section after cooling.

[0046] When the terminal post 10 is locally overheated, it may cause the upper plastic 11 to melt. The insulating sheet 13 and the sealing sheet can prevent the solution from passing through the cover plate 1 and entering the interior of the battery case.

[0047] It is worth mentioning that the cover plate 1 is made of two sections, namely the top cover sheet 2 and the lower plastic 5. As Figure 3 , 4 shown: The top cover sheet 2 is located above the lower plastic 5, and the perforation 3 is penetrated through the top cover sheet 2; the lower plastic 5 is correspondingly provided with a connection hole 6 penetrating through the perforation 3. The diameter of the connection hole 6 is smaller than the diameter of the perforation 3. The connection hole 6 and the perforation 3 are on the same axis. A top ring 7 is also provided on the top of the lower plastic 5 corresponding to the connection hole 6. The top ring 7 and the connection hole 6 are on the same axis, and the inner diameter of the top ring 7 is the same as the diameter of the connection hole 6, and the outer diameter of the top ring 7 is smaller than the inner diameter of the perforation 3. That is, after the lower plastic 5 is installed at the bottom of the top cover sheet 2, the top ring 7 can be inserted into the perforation 3. The bottom of the terminal post 10 is located on the top of the top ring 7, and a relief groove 8 is formed between the outer side wall of the top ring 7 and the inner side wall of the perforation 3. The sealing ring 9 is placed in the relief groove 8.

[0048] The top cover sheet 2 and the lower plastic 5 are detachably connected together. Specifically, the top cover sheet 2 and the lower plastic 5 are bonded together, and at the same time, the top cover sheet 2 and the lower plastic 5 can also be fixed together by bolts or buckles, that is, the quick disassembly and assembly of the top cover sheet 2 and the lower plastic 5 can be realized, so as to facilitate the subsequent maintenance of the battery.

[0049] At the same time, an explosion-proof valve 14 is also provided on the top of the top cover sheet 2. As Figure 4 shown: The explosion-proof valve 14 can release the overpressure through the rupture of the explosion-proof diaphragm to prevent the equipment from exploding, thereby increasing the safety of battery use.

[0050] Furthermore, an explosion-proof valve protection sheet 15 is provided at the bottom of the top cover sheet 2. The explosion-proof valve protection sheet 15 reduces the diaphragm fatigue by buffering the pressure fluctuation, thereby indirectly increasing the service life of the explosion-proof valve 14.

[0051] A storage bin 16 is provided on the lower plastic 5. The storage bin 16 has an opening facing the upper surface. The explosion-proof valve protection sheet 15 is placed in the storage bin 16 through this opening, that is, the storage bin 16 facilitates the fixing of the explosion-proof valve protection sheet 15.

[0052] In addition, it should also be noted that in the description of the present invention application, unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those skilled in the art, the specific meanings of the above terms in the present invention application can be understood according to the specific situation.

[0053] The above is the preferred embodiment of the present invention application. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle described in the present invention application, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present invention application.

Claims

1. A square battery cover plate structure, characterized in that: Comprising; A cover plate (1) with two through holes (3) formed therethrough; A pole column (10) placed in the through hole (3) for connection to an external circuit, the pole column (10) being in a boss-like structure; A sealing ring (9) located in the through hole (3) to provide support for the bottom of the pole column (10); An upper plastic (11) in an annular structure placed outside the pole column (10) to abut and position the bottom of the pole column (10), and the horizontal line of the upper surface of the upper plastic (11) is lower than the horizontal line of the upper surface of the pole column (10).

2. The structure of a square battery cover plate (1) as described in claim 1, characterized in that: A snap ring (4) is provided on the top of the cover plate (1) corresponding to the through hole (3), the sealing ring (9) and the pole column (10) are both located within the snap ring (4), and the horizontal line of the upper surface of the pole column (10) is higher than the horizontal line of the upper surface of the snap ring (4), and the cross section of the upper plastic (11) is in a loop structure to wrap the snap ring (4).

3. The structure of a square battery cover plate (1) according to claim 2, characterized in that: A support ring (12) is further sleeved outside the pole column (10), the support ring (12) is located above the bottom layer of the pole column (10) to fix the position of the pole column (10) within the snap ring (4), and the upper plastic (11) can wrap the support ring (12).

4. The structure of a square battery cover plate (1) as described in claim 1, characterized in that: The pole column (10) is in a three-stage boss structure, and the cross-sectional area of the pole column (10) gradually decreases from bottom to top.

5. The structure of a square battery cover plate (1) as described in claim 3, characterized in that: An insulating sheet (13) is further provided between the support ring (12) and the bottom layer of the pole column (10), the insulating sheet (13) is located at the bottom of the upper plastic (11), and the insulating sheet (13) is used to isolate the pole column (10) from the cover plate (1).

6. The structure of a square battery cover plate (1) as described in claim 1, characterized in that: The cover plate (1) is made of two sections, a top cover sheet (2) and a lower plastic (5), the top cover sheet (2) is located above the lower plastic (5), the through hole (3) is formed through the top cover sheet (2), the lower plastic (5) is provided with a connection hole (6) corresponding to the through hole (3), a top ring (7) is provided above the lower plastic (5) corresponding to the connection hole (6), the bottom of the pole column (10) is located at the top of the top ring (7), and a relief groove (8) is formed between the outer side wall of the top ring (7) and the inner side wall of the through hole (3), and the sealing ring (9) is placed in the relief groove (8).

7. The structure of a square battery cover plate (1) according to claim 6, characterized in that: The top cover sheet (2) and the lower plastic (5) are detachably connected together.

8. The structure of a square battery cover plate (1) according to claim 6 or 7, characterized in that: An explosion-proof valve (14) is provided on the top of the top cover sheet (2).

9. The structure of a square battery cover plate (1) as described in claim 8, characterized in that: An explosion-proof valve protection sheet is provided at the bottom of the top cover sheet (2).

10. The structure of a square battery cover plate (1) as described in claim 10, characterized in that: A storage bin (16) is provided on the lower plastic (5), and the explosion-proof valve protection sheet is located within the storage bin (16).

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