A welded injection-molded battery cover plate and a welding method thereof

Abstract

This invention discloses a welded injection-molded battery cover plate and its welding method, comprising a substrate and an electrode assembly. The substrate has electrode holes, including an upper hole and a lower hole that communicate with each other, forming a stepped surface between the upper hole and the lower hole. A welding ring is provided on the stepped surface, and a first receiving gap is formed between the welding ring and the electrode hole. The electrode assembly includes an electrode and a sealing ring sleeved on the outer side of the middle portion of the electrode, and a second receiving gap is formed between the electrode assembly and the welding ring. The substrate has an injection-molded edging, which has a portion extending into the first and second receiving gaps, and a portion located above the welding ring. After the injection-molded edging is processed on the substrate, the sealing ring is in a compressed state. This invention facilitates processing while ensuring the sealing and stability of the cover plate.

Description

Technical Field

[0001] This invention relates to the field of lithium battery technology, and in particular to a welded injection-molded battery cover plate and its welding method. Background Technology

[0002] With the development of power lithium batteries in my country, the technical requirements for battery top covers are becoming increasingly stringent. As the safety requirements for battery cells become higher and higher, the requirements for top covers are also becoming higher and higher. In order to improve the stability of the top cover structure and the overall safety and stability of power lithium batteries, the structure of the top cover must be improved.

[0003] A search revealed that Chinese patent application publication number CN118523017A, entitled "A Battery Cover Plate and Its Preparation Method", discloses a method of improving overall stability by filling a plastic ring between a fixing post and a fixing ring. Summary of the Invention

[0004] To address the technical problems existing in the background art, the present invention proposes a welded injection-molded battery cover plate and its welding method.

[0005] The present invention proposes a welded injection molded battery cover plate, comprising a substrate and an electrode assembly. The substrate has an electrode hole, which includes an upper hole and a lower hole that are connected. The diameter of the lower hole is smaller than that of the upper hole. A stepped surface is formed between the upper hole and the lower hole. A welding ring is provided on the stepped surface. A first accommodating gap is formed between the welding ring and the electrode hole.

[0006] The pole assembly includes a pole and a sealing ring sleeved on the outer side of the middle portion of the pole. The sealing ring has a small-diameter portion extending to the lower hole and a middle end face that contacts the stepped surface. A second receiving gap is formed between the pole assembly and the welding ring.

[0007] The substrate is provided with an injection-molded edge, the injection-molded edge having a portion extending into the first receiving interval and the second receiving interval, and the injection-molded edge having a portion located above the welding ring;

[0008] After the injection molding edge banding is performed on the substrate, the sealing ring is in a compressed state.

[0009] As a further optimization of the present invention, the welding ring has a through hole that connects the first accommodating interval and the second accommodating interval.

[0010] As a further optimization of the present invention, a snap-fit ​​groove is formed on the stepped surface, and a snap-fit ​​extension is provided at the bottom of the welding ring, the snap-fit ​​extension snapping into the snap-fit ​​groove.

[0011] As a further optimization of the present invention, the snap-fit ​​groove is arc-shaped, the snap-fit ​​extension is arc-shaped, the arc length of the snap-fit ​​groove is greater than the arc length of the snap-fit ​​extension, a filling gap is formed between the snap-fit ​​extension and the snap-fit ​​groove, and the injection-molded edge has a portion extending into the filling gap.

[0012] As a further optimization of the present invention, a support frame is provided between the welding ring and the pole post to make the pole post and the pole post hole coaxial.

[0013] Specifically, the support frame includes an inner ring, an outer ring, and a support rod disposed between the outer ring and the inner ring. The inner ring is sleeved on the outside of the pole post, and the outer ring abuts against the inner wall of the welding ring.

[0014] As a further optimization of the present invention, the outer ring has a first connecting hole and the welding ring has a second connecting hole. The first connecting hole and the second connecting hole are coaxial to form a connecting hole, and a positioning post for fixing the outer ring to the welding ring is provided in the connecting hole.

[0015] As a further optimization of the present invention, when the first connecting hole and the second connecting hole are coaxial, the sealing ring is in a compressed state.

[0016] As a further optimization of the present invention, a fixing post is provided on the inner ring, and a fixing hole matching the fixing post is opened on the pole post. After the fixing post matches the fixing hole, the pole post is pressed down to make the first connecting hole and the second connecting hole coaxial.

[0017] As a further optimization of the present invention, the positioning post has a positioning through hole, which connects the first accommodating interval and the interval between the outer ring and the inner ring.

[0018] A welding method for injection-molded battery cover plates includes the following steps:

[0019] S1. The welding ring is welded to the stepped surface of the substrate, and a first receiving gap is formed between the welding ring and the substrate.

[0020] S2. A sealing ring is installed on the outer sleeve of the pole post to form a pole post assembly;

[0021] S3. Mount the pole assembly on the substrate and compress the sealing ring, forming a second receiving gap between the welding ring and the pole assembly.

[0022] S4. An injection-molded edge is processed on the substrate by injection molding, and the injection-molded edge has a portion extending to the first receiving interval and the second receiving interval.

[0023] Preferably, a support frame is provided between the pole and the welding ring, and the support frame is connected to the welding ring to keep the sealing ring in a compressed state.

[0024] The proposed welding injection molded battery cover and its welding method are simple in structure, ensuring the overall stability of the cover while guaranteeing its sealing performance, and are easy to process.

[0025] Furthermore, the overall stability is improved by having a portion of the injection-molded edge extending to the through hole on the welding ring; similarly, the overall stability is further improved by having a portion of the injection-molded edge extending into the filling interval.

[0026] The support frame ensures that the electrode post and the electrode post hole on the substrate are coaxial, thus compressing the sealing ring and facilitating the injection molding edge wrapping process while ensuring sealing.

[0027] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of the present invention;

[0029] Figure 2 This is an exploded view of the present invention;

[0030] Figure 3 This is a cross-sectional view of the present invention;

[0031] Figure 4 This is a schematic diagram of the substrate structure of the present invention;

[0032] Figure 5 This is a schematic diagram of the welding ring structure of the present invention;

[0033] Figure 6 This is a schematic diagram of the unprocessed injection-molded edge-wrapping structure of the present invention;

[0034] Figure 7 This is a partial enlarged view of the pole post and welding ring portion in some embodiments of the present invention;

[0035] Figure 8 This is a schematic diagram of the support frame structure of the present invention;

[0036] In the figure: 1. Substrate; 10. Pole post hole; 100. Upper hole; 101. Lower hole; 102. Stepped surface; 103. Snap-fit ​​groove; 2. Welding ring; 20. Through hole; 21. Snap-fit ​​extension; 22. Second connection hole; 3. Pole post assembly; 30. Pole post; 300. Mounting ring groove; 301. Fixing hole; 31. Sealing ring; 310. Large diameter portion; 311. Small diameter portion; 4. First receiving interval; 5. Second receiving interval; 6. Injection molding edge wrap; 7. Support frame; 70. Outer ring; 700. First connection hole; 71. Inner ring; 72. Support rod; 8. Positioning post; 80. Positioning through hole; 9. Fixing post; 11. Stop frame; 12. Explosion-proof valve; 13. Pole plate; 14. Explosion-proof patch. Detailed Implementation

[0037] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar symbols denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0038] like Figure 1 - Figure 6 The illustrated welding injection molded battery cover includes a substrate 1, on which a terminal hole 10 is formed. The terminal hole 10 includes an upper hole 100 and a lower hole 101. The diameter of the lower hole 101 is smaller than that of the upper hole 100. A stepped surface 102 is formed between the upper hole 100 and the lower hole 101. A welding ring 2 is provided on the stepped surface 102. The welding ring 2 and the inner side surface of the terminal hole 10 form an annular first receiving gap 4.

[0039] like Figure 3 The diagram also includes a pole assembly 3, which includes a pole 30 and a sealing ring 31 sleeved outside the pole 30. The sealing ring 31 includes a large diameter portion 310 and a small diameter portion 311, which form an intermediate end face. The intermediate end face contacts the stepped surface 102, and the small diameter portion 311 abuts against the small hole.

[0040] like Figure 6 The pole post assembly 3 and the welding ring 2 form an annular second receiving interval 5. The substrate 1 is provided with an injection molding edge 6, which has a portion extending to the first receiving interval 4 and the second receiving interval 5. Between the first receiving interval 4 and the second receiving interval 5, when the injection molding edge 6 is processed on the substrate 1, the middle end face of the sealing ring 31 is in a compressed state.

[0041] like Figure 5 Preferably, the welding ring 2 has a through hole 20, which connects the first receiving interval 4 and the second receiving interval 5. The injection-molded edge has a portion extending into the through hole 20, thereby ensuring the stability of the connection.

[0042] like Figure 4 Preferably, the stepped surface 102 has a snap-fit ​​groove 103, and the bottom of the welding ring 2 has a snap-fit ​​extension 21 that snaps into the snap-fit ​​groove 103, thus facilitating the positioning of the welding ring 2. Preferably, the snap-fit ​​groove 103 has at least three sets, and the snap-fit ​​extension 21 has at least three sets.

[0043] Preferably, the snap-fit ​​groove 103 is an arc-shaped groove coaxial with the pole hole 10. The arc length of the snap-fit ​​groove 103 is greater than the arc length of the snap-fit ​​extension 21, and the width of the snap-fit ​​groove 103 is equal to the width of the snap-fit ​​extension 21, thereby ensuring that the welding ring 2 is coaxial with the pole hole 10. There is a filling gap between the snap-fit ​​groove 103 and the snap-fit ​​extension 21, and the injection-molded edge 6 has a portion that fills the filling gap, thereby ensuring the stability of the connection between the welding ring 2 and the base.

[0044] like Figure 7 - Figure 8 As shown, in some embodiments, preferably, a support frame 7 is provided between the welding ring 2 and the pole post 30 to ensure that the pole post 30 and the pole post hole 10 are coaxial. The support frame 7 includes an outer ring 70 and an inner ring 71, and a support rod 72 disposed between the outer ring 70 and the inner ring 71. The inner ring 71 is sleeved on the outside of the pole post 30, and the outer ring 70 is in contact with the welding ring 2.

[0045] like Figure 7 Preferably, the pole post 30 has a mounting ring groove 300, and the end face of the inner ring 71 contacts the bottom of the mounting ring groove 300, thereby facilitating the positioning of the support ring.

[0046] like Figure 7 Preferably, the outer ring 70 has a first connecting hole 700, and the welding ring 2 has a second connecting hole 22. The first connecting hole 700 and the second connecting hole 22 are coaxial to form a connecting hole, and a positioning pin 8 is inserted into the connecting hole. This ensures stability while further guaranteeing sealing.

[0047] Preferably, when the positioning pin 8 is inserted into the connecting hole, that is, when the first positioning hole and the second positioning hole are coaxial, the sealing ring 31 is in a compressed state, which ensures its sealing performance and facilitates the processing of the injection molding edge banding 6.

[0048] like Figure 7Preferably, to prevent the inner ring 71 from moving relative to the outer ring 70, the inner ring 71 is provided with a fixing post 9, and the pole post 30 is provided with a fixing hole 301 that matches the fixing post 9. The fixing hole 301 is opened on the mounting ring groove 300. During the installation of the support frame 7, the inner ring 71 is first sleeved on the pole post 30, and the fixing post 9 is engaged with the fixing hole 301. Then, the pole post 30 is pressed down to compress the sealing ring 31, thereby driving the outer ring 70 to move downward so that the first connecting hole 700 and the second connecting hole 22 are aligned to form a connecting hole. Then, the positioning post 8 is installed. After the positioning post 8 is installed, the outer ring 70 and the welding ring 2 are fixed in position, thereby keeping the sealing ring 31 in a compressed state.

[0049] like Figure 7 Preferably, the positioning post 8 has a positioning through hole 80, which connects the first accommodating interval 4 and the interval between the outer ring 70 and the inner ring 71 of the support frame 7. The injection-molded edge 6 has a portion extending into the positioning through hole 80, which further enhances its stability while ensuring sealing.

[0050] like Figure 1 Preferably, the system also includes a stop frame 11, which is mounted on the bottom of the substrate 1. Specifically, the stop frame 11 is connected to the substrate 1 by thermoforming welding. The stop frame 11 has an extended protruding ring for abutting against the sealing ring 31, thereby facilitating the positioning of the stop frame 11 and the substrate 1.

[0051] Like existing technologies, such as Figure 2 As shown, an explosion-proof valve 12 is welded onto the substrate 1, and an explosion-proof patch 14 is provided on the substrate 1, with the explosion-proof patch 14 facing the explosion-proof valve 12.

[0052] It also includes an electrode 13, which is welded to the electrode post 30 by welding. The stop frame 11 has a positioning groove, and one side of the electrode 13 is inserted into the positioning groove. The electrode 13 has a protrusion, which is welded to the electrode post 30.

[0053] In this embodiment, during the working process: First, the snap-fit ​​extension 21 of the welding ring 2 is placed in the snap-fit ​​groove 103. Then, a clamping block is placed in the filling interval of the snap-fit ​​groove 103 to restrict the snap-fit ​​extension 21 within the snap-fit ​​groove 103, so as to prevent the welding ring 2 from rotating relative to the base. Then, the middle part of the three snap-fit ​​extensions 21 is welded to the substrate 1 by welding. Then, the clamping block is removed, and all the contact parts between the welding ring 2 and the substrate 1 are welded.

[0054] Then, the sealing ring 31 is sleeved on the outside of the pole post 30. Specifically, the pole post 30 includes an upper conductive part, a lower conductive part, and an intermediate part for connecting the upper conductive part and the lower conductive part. The outer diameter of the intermediate part is larger than the outer diameter of the lower conductive part and the upper conductive part. The small diameter part 311 of the sealing ring 31 is sleeved on the outside of the lower conductive part, and the large diameter part 310 of the sealing ring 31 is sleeved on the outside of the intermediate part, ensuring that the separating surfaces of the large diameter part 310 and the small diameter part 311 of the sealing ring 31 are pressed against the intermediate part to form the pole post assembly 3.

[0055] Place the pole assembly 3 in the pole hole 10 so that the small diameter part 311 matches the lower hole 101 and the middle end face contacts the stepped surface 102. Sleeve the support frame 7 between the pole 30 and the welding ring 2, and insert the positioning pin 8 into the connection hole to fix the support frame 7 on the welding ring 2. During the installation of the positioning pin 8, press the pole 30 down to compress the sealing ring 31 part. To avoid the ring on the cover being opposite after the connector is installed;

[0056] The injection molding edge 6 is processed on the substrate 1 by injection molding. The injection molding edge 6 has a through hole 20 extending to the first receiving interval 4, the second receiving interval 5, the welding ring 2, and a portion for filling the interval. The pole post assembly 3 is fixed to the substrate 1 by the injection molding edge 6.

[0057] The explosion-proof valve 12 is welded onto the substrate 1;

[0058] The stop bracket is fixed to the substrate 1 by heat fusion, and the explosion-proof patch 14 is attached to the hole on the substrate 1 opposite to the explosion-proof valve 12.

[0059] It should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the present invention 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 the present invention.

[0060] 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 at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0061] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "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, an electrical connection, or a connection that allows communication between the components; 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, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0062] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature.

[0063] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A welded injection-molded battery cover, characterized in that, The assembly includes a substrate (1) and an electrode assembly (3). The substrate (1) has an electrode hole (10). The electrode hole (10) includes an upper hole (100) and a lower hole (101) that are connected. The diameter of the lower hole (101) is smaller than the diameter of the upper hole (100). A stepped surface (102) is formed between the upper hole (100) and the lower hole (101). A welding ring (2) is provided on the stepped surface (102). A first receiving gap (4) is formed between the welding ring (2) and the electrode hole (10). The pole assembly (3) includes a pole (30) and a sealing ring (31) sleeved on the outer side of the middle part of the pole (30). The sealing ring (31) has a small diameter portion (311) extending to the lower hole (101). The sealing ring (31) has an intermediate end face that contacts the stepped surface (102). A second receiving gap (5) is formed between the pole assembly (3) and the welding ring (2). The substrate (1) is provided with an injection-molded edge (6), the injection-molded edge (6) having a portion extending into the first receiving interval (4) and the second receiving interval (5); After the injection molding edge banding (6) is processed on the substrate (1), the sealing ring (31) is in a compressed state; A support frame (7) is provided between the welding ring (2) and the pole post (30) to make the pole post (30) coaxial with the pole post hole (10); The support frame (7) includes an inner ring (71), an outer ring (70), and a support rod (72) disposed between the outer ring (70) and the inner ring (71). The inner ring (71) is sleeved on the pole post (30), and the outer ring (70) abuts against the inner wall of the welding ring (2). The outer ring (70) has a first connecting hole (700), and the welding ring (2) has a second connecting hole (22). The first connecting hole (700) and the second connecting hole (22) are coaxial to form a connecting hole. The connecting hole is provided with a positioning post (8) for fixing the outer ring (70) on the welding ring (2).

2. The welded injection-molded battery cover plate according to claim 1, characterized in that, The welding ring (2) has a through hole (20) that connects the first accommodating interval (4) and the second accommodating interval (5).

3. The welded injection-molded battery cover plate according to claim 1, characterized in that, The stepped surface (102) has a snap-fit ​​groove (103), and the bottom of the welding ring (2) is provided with a snap-fit ​​extension (21), which snaps into the snap-fit ​​groove (103).

4. The welded injection-molded battery cover plate according to claim 3, characterized in that, The snap-fit ​​groove (103) is arc-shaped, the snap-fit ​​extension (21) is arc-shaped, the arc length of the snap-fit ​​groove (103) is greater than the arc length of the snap-fit ​​extension (21), a filling gap is formed between the snap-fit ​​extension (21) and the snap-fit ​​groove (103), and the injection-molded edge band (6) has a portion extending into the filling gap.

5. The welded injection-molded battery cover plate according to claim 1, characterized in that, The inner ring (71) is provided with a fixing post (9), and the pole post (30) is provided with a fixing hole (301) that matches the fixing post (9). After the fixing post (9) matches the fixing hole (301), the pole post (30) is pressed down so that the first connecting hole (700) and the second connecting hole (22) are coaxial.

6. The welded injection-molded battery cover plate according to claim 1 or 5, characterized in that, The positioning post (8) has a positioning through hole (80) that connects the first accommodating interval (4) and the interval between the outer ring (70) and the inner ring (71).

7. A welding method for injection-molded battery cover plates, used for the injection-molded battery cover plates according to any one of claims 1-6, characterized in that, The steps include the following: S1. Weld the welding ring (2) onto the stepped surface (102) of the substrate (1), and a first receiving gap is formed between the welding ring (2) and the substrate (1); S2. A sealing ring (31) is fitted over the pole post (30) to form a pole post assembly (3); S3. Mount the pole assembly (3) on the substrate (1) and compress the sealing ring (31), forming a second receiving gap between the welding ring (2) and the pole assembly (3); S4. An injection molding edge (6) is processed on the substrate (1) by injection molding. The injection molding edge (6) has a portion extending to the first receiving interval and the second receiving interval.

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