Leading-out end connecting structure of secondary battery

Abstract

The utility model discloses a leading-out terminal connecting structure of a secondary battery, which comprises an upper pole, an upper sealing gasket, a lower sealing gasket, a sealing piece and a current collecting piece, the upper pole, the upper sealing gasket, the lower sealing gasket, the sealing piece and the current collecting piece are sequentially arranged from top to bottom, and the middle of the upper pole is concave inwards to form a concave part; the upper sealing gasket is arranged between the upper pole and the battery shell, and the lower sealing gasket is arranged between the battery shell and the sealing element; the upper sealing gasket and the lower sealing gasket are both provided with through holes matched with the inner concave parts; the sealing piece is arranged between the lower sealing gasket and the current collecting piece, and a protruding part is arranged in the middle of the current collecting piece; the sealing piece is provided with a through hole matched with the protruding part. The concave part of the upper pole is inserted into the through holes of the upper sealing gasket, the battery shell and the lower sealing gasket, the bottom end of the concave part is connected with the top end of the sealing piece, the lug boss of the current collector penetrates through the through hole of the sealing piece, and the top end of the lug boss is connected with the bottom end of the concave part.

Description

Technical Field

[0001] The utility model belongs to the technical field of battery sealing welding, and in particular relates to a lead-out terminal connection structure of a secondary battery. Background Art

[0002] In a square battery, it is generally composed of a metal battery case with an oblong or rectangular cross-sectional shape, an external lead-out terminal, an insulating sealing component and a current collector (positive plate, negative plate) to accommodate the current collector and the electrolyte in the battery case. The lead-out terminal is usually fixed on the long side of the case and contacts the positive plate through the opening of the battery case.

[0003] In the prior art, the lead-out terminal structure of a sealed battery has a concave step in the middle of the external positive terminal, and the flat part of the step is connected to the positive plate through a seal. "Three-layer welding" is adopted, that is, the inner wall of the concave part, the seal, and the current collector need to be welded together. Due to the large thickness of the weld, the following technical problems often exist when laser welding is adopted: 1. The welding power is too large, and bubbles are easily generated at the welding position; 2. The welding quality is poor, resulting in poor conductivity and sealing performance of the battery; 3. After welding, the insulating sealing component between the upper pole (or seal) and the battery shell will bend and deform due to the large force, resulting in poor air tightness of the battery. Utility Model Content

[0004] The purpose of the utility model is to provide a lead-out terminal connection structure of a secondary battery to solve the technical problems in the background technology.

[0005] The technical solution of the utility model is as follows: a secondary battery lead-out terminal connection structure, comprising an upper pole, an upper sealing gasket, a lower sealing gasket, a seal and a current collecting sheet, wherein the upper pole, the upper sealing gasket, the lower sealing gasket, the seal and the current collecting sheet are arranged in sequence from top to bottom, and the middle of the upper pole is concave to form an inner concave portion;

[0006] The upper sealing gasket is arranged between the upper pole and the battery housing, and the lower sealing gasket is arranged between the battery housing and the sealing member. The upper sealing gasket and the lower sealing gasket cooperate to form an insulating sealing member to prevent the upper pole, the sealing member and the battery housing from contacting each other; the upper sealing gasket and the lower sealing gasket are both provided with through holes adapted to the inner recess;

[0007] The sealing member is arranged between the lower sealing pad and the current collecting sheet, a convex portion is arranged in the middle of the current collecting sheet; the sealing member is provided with a through hole adapted to the convex portion;

[0008] The concave portion of the upper pole is inserted into the through holes of the upper sealing gasket, the battery housing and the lower sealing gasket, the bottom end of the concave portion is connected to the top end of the seal, the convex portion of the current collector passes through the through hole of the seal, and the top end of the convex portion is connected to the bottom end of the concave portion.

[0009] Beneficial effects of the above technical scheme: Compared with the prior art, the utility model is a lead-out terminal connection structure of a secondary battery, which effectively improves the overall structure and assembly method of the upper pole, upper sealing gasket, lower sealing gasket, seal and current collector; the concave portion of the upper pole is inserted into the through hole of the upper sealing gasket, the battery shell and the lower sealing gasket, the bottom end of the concave portion is connected to the top end of the seal, the convex portion of the current collector passes through the through hole of the seal, and the top end of the convex portion is connected to the bottom end of the concave portion, and the current collector also serves as the lower pole to ensure that its welding power is small, bubbles are not easy to generate at the welding position, the conductivity is improved, and the poor welding quality leads to poor battery conductivity and sealing performance. Technical problems.

[0010] In a preferred solution, the bottom end of the inner recessed portion is fixed to the top end of the sealing member by welding, and the top end of the raised portion is fixed to the bottom end of the inner recessed portion by welding.

[0011] The above technical solution has the beneficial effects that the bottom end of the recessed portion and the top end of the seal are fixed by welding, and the top end of the raised portion and the bottom end of the recessed portion are fixed by welding, thereby further ensuring that the welding power is small, bubbles are not easily generated at the welding position, and the welding quality is ensured, thereby ensuring the conductivity and sealing performance of the battery.

[0012] In a preferred solution, the upper sealing gasket comprises a planar portion and a columnar portion, the upper surface of the planar portion is provided with a first groove, and the lower surface of the upper pole is provided with a first protrusion matching the first groove at a corresponding position.

[0013] The above technical solution has the beneficial effect that the first groove and the first protrusion are tightly matched to ensure the insulation sealing between the upper sealing gasket and the upper pole.

[0014] In a preferred solution, a second groove is provided on the lower surface of the lower sealing pad, and a second protrusion matching the second groove is provided at a corresponding position on the upper surface of the sealing member.

[0015] The above technical solution has the beneficial effect that the insulation sealing between the lower sealing gasket and the sealing member is further ensured by the close cooperation between the second groove and the second protrusion.

[0016] In a preferred solution, the upper sealing gasket is clamped and fixed between the upper pole and the battery housing, and the lower sealing gasket is clamped and fixed between the sealing member and the battery housing to form an insulating sealing member.

[0017] The above technical solution has the beneficial effect that the upper sealing gasket and the lower sealing gasket are clamped and fixed between the upper pole and the battery housing by welding the inner recess of the upper pole and the sealing member to ensure the insulation and sealing of the upper pole and the battery housing.

[0018] In a preferred solution, the inner concave portion of the upper pole is circular.

[0019] The above technical solution has the beneficial effect that by designing the inner recess of the upper pole to be circular, the circular inner recess can effectively change the force applied thereto to ensure that the insulating sealing assembly between the upper pole and the battery housing will not bend and deform due to the large force, thereby ensuring the air tightness of the battery.

[0020] In a preferred solution, the lower sealing pad and the sealing member are each provided with two positioning holes, and the two positioning holes are symmetrically arranged with respect to the through hole.

[0021] The above technical solution has the beneficial effect of: two positioning holes are provided on the lower sealing gasket and the sealing member to ensure accurate positioning during installation of the lower sealing gasket and welding of the sealing member to the bottom end of the inner recessed portion, thereby further ensuring the welding quality.

[0022] In a preferred solution, a protrusion is provided at the lower end of the columnar portion, and a groove is provided at the lower sealing gasket corresponding to the position of the protrusion, so that the upper sealing gasket and the lower sealing gasket fit tightly.

[0023] The above technical solution has the beneficial effect that the insulation sealing of the upper sealing gasket and the lower sealing gasket is further ensured by the close cooperation between the protrusion and the groove. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 A schematic cross-sectional view of an assembly of a lead-out terminal connection structure of a secondary battery provided in Example 1 of the utility model;

[0026] Figure 2 A schematic diagram of the overall structure of the upper pole provided in Example 1 of the utility model;

[0027] Figure 3 A top view of the upper sealing gasket provided in Example 1 of the utility model;

[0028] Figure 4 A schematic diagram of the battery housing assembly provided in Example 1 of the utility model;

[0029] Figure 5 A top view of the lower sealing gasket provided in Example 1 of the utility model;

[0030] Figure 6 A top view of the sealing member provided in Example 1 of the utility model;

[0031] Figure 7 A top view of the current collecting sheet provided in Example 1 of the utility model;

[0032] Figure 8 A cross-sectional view of a lead-out terminal connection structure of a secondary battery provided in Example 1 of the utility model;

[0033] Description of reference numerals;

[0034] 1-upper pole; 101-first step; 2-upper sealing gasket; 201-planar part; 202-columnar part; 3-lower sealing gasket; 4-seal; 5-current collector; 6-battery housing; 7-raised part; 8-first groove; 9-first protrusion; 10-second groove; 11-second protrusion; 12-bump; 13-groove. DETAILED DESCRIPTION

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0036] It should be noted that the "upper", "lower", "left", "right", "front" and "back" mentioned in this article to describe the direction do not refer to the direction unless otherwise specified, but are only for the convenience of description. The description of the product will be different if it is placed in a different direction. Any direction that can be understood by ordinary technicians in this field without making creative work belongs to the protection scope of this utility model.

[0037] Example 1

[0038] like Figures 1 to 8 As shown, a terminal connection structure of a secondary battery includes an upper pole 1, an upper sealing gasket 2, a lower sealing gasket 3, a seal 4 and a current collecting sheet 5, wherein the upper pole 1, the upper sealing gasket 2, the lower sealing gasket 3, the seal 4 and the current collecting sheet 5 are arranged in sequence from top to bottom, and the middle of the upper pole 1 is concave to form a concave portion 101;

[0039] The upper sealing gasket 2 is arranged between the upper pole 1 and the battery housing 6, and the lower sealing gasket 3 is arranged between the battery housing 6 and the sealing member 4. The upper sealing gasket 2 and the lower sealing gasket 3 cooperate to form an insulating sealing member to prevent the upper pole 1 and the sealing member 4 from contacting the battery housing 6; the upper sealing gasket 2 and the lower sealing gasket 3 are both provided with through holes adapted to the inner recess 101;

[0040] The sealing member 4 is arranged between the lower sealing pad 3 and the current collecting sheet 5, and a protrusion 7 is arranged in the middle of the current collecting sheet 5; the sealing member 4 is provided with a through hole adapted to the protrusion 7;

[0041] The concave portion 101 of the upper pole 1 is inserted into the through holes of the upper sealing gasket 2, the battery shell 6 and the lower sealing gasket 3, the bottom end of the concave portion 101 is connected to the top end of the seal 4, the raised portion 7 of the current collector 5 passes through the through hole of the seal 4, and the top end of the raised portion 7 is connected to the bottom end of the concave portion 101; the overall structure and assembly method of the upper pole 1, the upper sealing gasket 2, the lower sealing gasket 3, the seal 4 and the current collector 5 are effectively improved; the concave portion 101 of the upper pole 1 is inserted into the through holes of the upper sealing gasket 2, the battery shell 6 and the lower sealing gasket 3, the bottom end of the concave portion 101 is connected to the top end of the seal 4, the raised portion 7 of the current collector 5 passes through the through hole of the seal 4, and the top end of the raised portion 7 is connected to the bottom end of the concave portion 101, so as to ensure that the welding power is small, bubbles are not easy to be generated at the welding position, the conductivity is improved, and the poor welding quality, which leads to poor battery conductivity and sealing performance, and other technical problems.

[0042] In this embodiment, the current collecting sheet 5 is a positive electrode current collecting sheet or a negative electrode current collecting sheet.

[0043] In this embodiment, the bottom end of the recessed portion 101 is welded to the top end of the seal 4, and the welding point is circular; the top end of the raised portion 7 is welded to the bottom end of the recessed portion 101; the bottom end of the recessed portion 101 is fixed to the top end of the seal 4 by welding, and the top end of the raised portion 7 is fixed to the bottom end of the recessed portion 101 by welding, which further ensures that the welding power is small, bubbles are not easily generated at the welding position, and the welding quality is ensured, thereby ensuring the conductivity and sealing performance of the battery.

[0044] Furthermore, the welding method adopts laser welding, ultrasonic welding, etc., which is the existing technology in this field.

[0045] In this embodiment, the upper sealing gasket 2 includes a planar portion 201 and a cylindrical portion 202. The upper surface of the planar portion 201 is provided with a first groove 8, and the corresponding position of the lower surface of the upper pole 1 is provided with a first protrusion 9 adapted to the first groove 8; the first groove 8 and the first protrusion 9 are tightly matched to ensure the insulation sealing between the upper sealing gasket 2 and the upper pole 1.

[0046] In this embodiment, a second groove 10 is provided on the lower surface of the lower sealing gasket 3, and a second protrusion 11 matching the second groove 10 is provided at a corresponding position on the upper surface of the sealing member 4; the second groove 10 and the second protrusion 11 are closely matched to further ensure the insulation sealing between the lower sealing gasket 3 and the sealing member 4.

[0047] In this embodiment, the upper sealing gasket 2 is clamped and fixed between the upper pole 1 and the battery shell 5, and the lower sealing gasket 3 is clamped and fixed between the sealing member 4 and the battery shell 6 to form an insulating seal; the upper sealing gasket 2 and the lower sealing gasket 3 are both clamped and fixed between the upper pole 1 and the battery shell 6 by welding the inner recess 101 of the upper pole 1 and the sealing member 4 to ensure the insulating sealing of the upper pole 1 and the battery shell 6.

[0048] In this embodiment, the inner recess 101 of the upper pole 1 is circular; the inner recess 101 of the upper pole 1 is designed to be circular, and the circular inner recess 101 can effectively change the force thereof to ensure that the insulating sealing assembly between the upper pole 1 and the battery housing 6 will not bend and deform due to the large force, thereby ensuring the airtightness of the battery.

[0049] In this embodiment, two positioning holes are provided on the lower sealing gasket 3 and the sealing member 4, and the two positioning holes are symmetrically arranged about the through hole; through the two positioning holes provided on the lower sealing gasket 3 and the sealing member 4, the lower sealing gasket 3 is installed and the sealing member 4 is accurately positioned when welding with the bottom end of the inner recess 101, thereby further ensuring the welding quality.

[0050] In this embodiment, a protrusion 12 is provided at the lower end of the cylindrical part 202, and a groove 13 is provided at the lower sealing gasket 3 corresponding to the position of the protrusion, so that the upper sealing gasket 2 and the lower sealing gasket 3 are tightly matched; through the tight fit between the protrusion 12 and the groove 13, the insulation sealing of the upper sealing gasket 2 and the lower sealing gasket 3 is further ensured.

[0051] Specific usage of this utility model:

[0052] Step 1: Place the tooling base on the workbench;

[0053] Step 2: First, the seal 4, the lower seal 3, the battery housing 6, the upper seal 2, and the upper pole 1 are introduced and placed on the tooling base in order, and the bottom end of the inner concave portion 101 of the upper pole 1 is fixed to the top end of the seal 4 by laser welding;

[0054] Step 3: Then put the battery cell into the battery housing 6 so that the raised portion 7 of the lower current collector 5 passes through the through hole of the seal 4, and fix the top of the raised portion 7 and the bottom of the recessed portion 101 by laser welding.

[0055] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention.

[0056] The above are only preferred implementations of the utility model. It should be pointed out that due to the limitations of textual expression and the objective existence of infinite specific structures, ordinary technicians in this technical field can make several improvements, modifications or changes without departing from the principles of the utility model, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the concept and technical solution of the utility model to other occasions without improvement, should all be regarded as protection of the utility model.

Claims

1. A lead-out terminal connection structure of a secondary battery, characterized in that: It comprises an upper pole (1), an upper sealing gasket (2), a lower sealing gasket (3), a sealing member (4) and a current collecting sheet (5), wherein the upper pole (1), the upper sealing gasket (2), the lower sealing gasket (3), the sealing member (4) and the current collecting sheet (5) are arranged in sequence from top to bottom, and the middle of the upper pole (1) is concave to form an inner concave portion (101); The upper sealing gasket (2) is arranged between the upper pole (1) and the battery housing (6), and the lower sealing gasket (3) is arranged between the battery housing (6) and the sealing member (4); the upper sealing gasket (2) and the lower sealing gasket (3) cooperate to form an insulating sealing member to prevent the upper pole (1), the sealing member (4) and the battery housing (6) from contacting each other; the upper sealing gasket (2) and the lower sealing gasket (3) are both provided with through holes adapted to the inner recess (101); The sealing member (4) is arranged between the lower sealing pad (3) and the current collecting sheet (5); a protrusion (7) is provided in the middle of the current collecting sheet (5); and the sealing member (4) is provided with a through hole matched with the protrusion (7); The inner recess (101) of the upper pole (1) is inserted into the through holes of the upper sealing gasket (2), the battery housing (6) and the lower sealing gasket (3); the bottom end of the inner recess (101) is connected to the top end of the sealing member (4); the raised portion (7) of the current collecting sheet (5) passes through the through hole of the sealing member (4); and the top end of the raised portion (7) is connected to the bottom end of the inner recess (101).

2. The lead-out terminal connection structure of a secondary battery according to claim 1, characterized in that: The bottom end of the inner recess (101) and the top end of the sealing member (4) are fixed by welding, and the top end of the raised portion (7) and the bottom end of the inner recess (101) are fixed by welding.

3. The lead-out terminal connection structure of a secondary battery according to claim 1, characterized in that: The upper sealing gasket (2) comprises a plane portion (201) and a columnar portion (202); a first groove (8) is provided on the upper surface of the plane portion (201); and a first protrusion (9) matching the first groove (8) is provided at a corresponding position on the lower surface of the upper pole (1).

4. The lead-out terminal connection structure of a secondary battery according to claim 1, characterized in that: The lower surface of the lower sealing pad (3) is provided with a second groove (10), and a corresponding position of the upper surface of the sealing element (4) is provided with a second protrusion (11) matching the second groove (10).

5. The lead-out terminal connection structure of a secondary battery according to claim 1, characterized in that: The upper sealing gasket (2) is clamped and fixed between the upper pole (1) and the battery housing (6), and the lower sealing gasket (3) is clamped and fixed between the sealing member (4) and the battery housing (6), thereby forming an insulating sealing member.

6. The lead-out terminal connection structure of a secondary battery according to claim 1, characterized in that: The inner concave portion (101) of the upper pole (1) is circular.

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