Cap structure capable of enhancing overcurrent capability and lithium battery

Abstract

The utility model provides a cap structure capable of enhancing overcurrent capability and a lithium battery, the cap structure comprises a top cover and an anti-explosion sheet, the anti-explosion sheet wraps the periphery of the top cover and is connected with the top cover through welding; an upper top plate protruding in the direction away from the anti-explosion piece is arranged in the middle of the top cover, and a plurality of pressure relief holes penetrating through the top cover are formed in the upper top plate at intervals. An anti-explosion area corresponding to the upper top plate in position is arranged on the anti-explosion piece, a filling area is arranged on the outer side of the anti-explosion area, and a conduction piece is arranged on the side, close to the top cover, of the filling area; according to the anti-explosion cap, the conduction piece is arranged, on the basis that the top cover and the anti-explosion piece are welded, the contact area between the top cover and the anti-explosion piece is increased, and the conductivity of the cap is enhanced.

Description

Technical Field

[0001] The utility model relates to the technical field of battery manufacturing, in particular to a cap structure and a lithium battery capable of enhancing overcurrent capacity.

Background Art

[0002] The cylindrical battery is a battery with high capacity, long cycle life and wide operating temperature range; the battery cap is a protective component covering the battery, usually made of plastic or metal materials, and its main function is to protect the battery from the external environment and potential damage; the conventional combined cap structure includes: a top cover (electrode cap), PTC, explosion-proof sheet, spacer, hole plate (aluminum bottom plate), sealing ring; the top cover or electrode cap plays a supporting role and is also the positive extreme of the battery for output. The shapes and structures of the top covers adopted by different battery manufacturers and different models of batteries may vary; PTC means positive temperature coefficient, which refers to a positive temperature coefficient thermistor in the battery. Its characteristic is that when the temperature exceeds a certain value, its resistance value increases step by step with the increase of temperature; the explosion-proof aluminum sheet includes Vent and C ID. Vent is a safety valve, and C ID refers to a current cut-off device, which specifically refers to the part of the welded connection between the explosion-proof sheet and the hole plate in the cap structure; in the traditional mechanical cap (such as CN218242020U), the top cover and the explosion-proof sheet are electrically connected by welding, resulting in a problem that the actual conduction area is too small, and the current can only be conducted through the welded part between the top cover and the explosion-proof sheet, leading to a long electronic path and transmission lag, thereby affecting the performance of the battery.

[0003] In view of this, the utility model provides a cap structure and a lithium battery capable of enhancing overcurrent capacity to solve the above problems.

Content of the Utility Model

[0004] The purpose of the utility model is to provide a cap structure and a lithium battery capable of enhancing overcurrent capacity. On the basis of welding the top cover and the explosion-proof sheet, the contact area between the top cover and the explosion-proof sheet is increased, the internal resistance is reduced, and the conductive capacity of the cap is enhanced.

[0005] To achieve the above purpose, the technical solution adopted by the utility model is: a cap structure capable of enhancing overcurrent capacity, including a top cover and an explosion-proof sheet, the top cover is adjacent to the explosion-proof sheet and is connected to the explosion-proof sheet by welding; the top cover includes an upper cover plate and an upper top plate connected to the upper cover plate, and the upper top plate protrudes towards the direction away from the explosion-proof sheet; a plurality of pressure relief holes are arranged at intervals on the upper top plate; an explosion-proof area and a filling area surrounding the explosion-proof area are arranged on the explosion-proof sheet, and the pressure relief holes penetrate through the upper top plate and are directly opposite to the explosion-proof area; a conduction member is arranged on one side of the filling area close to the top cover, and the conduction member is used to connect the top cover and the explosion-proof sheet to enhance the electrical conduction area between the top cover and the explosion-proof sheet.

[0006] On the basis of the above solution, a flanging is formed on the peripheral side of the explosion-proof sheet, and the flanging covers the peripheral edge of the top cover; the connection between the flanging and the upper cover plate is laser welded to realize the electrical connection between the explosion-proof sheet and the top cover.

[0007] On the basis of the above solution, the explosion-proof area is circular and is directly opposite to the upper top plate.

[0008] On the basis of the above solution, the filling area is located between the explosion-proof area and the flanging; the filling area is annular.

[0009] On the basis of the above solution, the conductive member is a metal conductive adhesive.

[0010] On the basis of the above solution, the upper top plate includes a connecting portion and an abutting portion, and the connecting portion is located between the upper cover plate and the abutting portion; the pressure relief holes are arranged in the connecting portion, and a plurality of the pressure relief holes are arranged at intervals around the abutting portion.

[0011] On the basis of the above solution, explosion-proof scoring lines are arranged in the direction away from the top cover on the explosion-proof sheet, and the explosion-proof scoring lines are the outer edge lines of the explosion-proof area.

[0012] In addition, to solve the above problems, the present utility model further provides a lithium battery, including a steel shell, a winding core arranged in the steel shell, and the above-mentioned cap structure capable of enhancing the overcurrent capacity.

[0013] Compared with the prior art, the present utility model provides a cap structure capable of enhancing the overcurrent capacity, including a top cover and an explosion-proof sheet, the explosion-proof sheet covers the peripheral edge of the top cover and is connected to the top cover by welding; a convex upper top plate is arranged in the middle of the top cover in the direction away from the explosion-proof sheet, and a plurality of pressure relief holes penetrating the top cover are arranged at intervals on the upper top plate; an explosion-proof area corresponding to the position of the upper top plate is arranged on the explosion-proof sheet, a filling area is arranged outside the explosion-proof area, and a conductive member is arranged on the side of the filling area close to the top cover; by arranging the conductive member in the present application, on the basis of welding the top cover and the explosion-proof sheet, the contact area between the top cover and the explosion-proof sheet is increased, the internal resistance is reduced, and thus the conductive ability of the cap is enhanced.

Description of the Drawings

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the drawings required to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present utility model, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0015] Figure 1 Partial exploded view of the cap structure provided by the present utility model;

[0016] Figure 2 is Figure 1 The cross-sectional view taken along A-A shown in

[0017] As shown in the figure: cap structure 100;

[0018] Top cover 10, upper cover plate 101, upper top plate 102, connecting portion 1021, abutting portion 1022, pressure relief hole 103;

[0019] Explosion-proof film 20, explosion-proof area 201, filling area 202, flanging 203, explosion-proof engraved line 204;

[0020] Conduction member 30;

Specific embodiments

[0021] In order to make the purpose, technical solutions and beneficial technical effects of the present utility model clearer and more understandable, the present utility model will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described in this specification are only for explaining the present utility model and not for limiting the present utility model.

[0022] It should also be understood that the terms used in this specification of the present utility model are only for the purpose of describing specific embodiments and are not intended to limit the present utility model. As used in this specification of the present utility model and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms.

[0023] It should be further understood that the term " / and" used in this specification of the present utility model and the appended claims refers to any combination and all possible combinations of one or more of the related listed items, and includes these combinations.

[0024] As Figure 1-2 shown, the present utility model provides a cap structure 100 that can enhance the overcurrent capacity, including a top cover 10 and an explosion-proof film 20. The top cover 10 is adjacent to the explosion-proof film 20 and is connected to the explosion-proof film 20 by welding; it should be noted that the attached Figure 1-2 Only shows the schematic structural diagram between the top cover 10 and the explosion-proof film 20 in the cap structure 100 of the present application, and the purpose is to show the content to be protected by the present application, that is, the conductive structure between the top cover 10 and the explosion-proof film 20.

[0025] Specifically, the top cover 10 includes an upper cover plate 101 and an upper top plate 102. The upper top plate 102 is located in the middle of the top cover 10, and the upper top plate 102 is provided with a protrusion towards the direction away from the explosion-proof film 20; a plurality of pressure relief holes 103 are arranged at intervals on the upper top plate 102; an explosion-proof area 201 and a filling area 202 surrounding the explosion-proof area 201 are arranged on the explosion-proof film 20. The pressure relief holes 103 penetrate through the upper top plate 102 and are directly opposite to the explosion-proof area 201; a conduction member 30 is arranged on one side of the filling area 202 close to the explosion-proof film 20. The conduction member 30 is used to connect the top cover 10 and the explosion-proof film 20 to increase the electrically conductive area between the top cover 10 and the explosion-proof film 20; in a traditional battery, the welding point between the top cover 10 and the explosion-proof film 20 is the current transmission channel of the battery, and there is a problem that the actual conductive area is too small, and the current can only be conducted through the welding part of the top cover 10 and the explosion-proof film 20, resulting in a long electronic path and transmission lag; that is, in this application, by arranging the conduction member 30 between the top cover 10 and the explosion-proof film 20, the conductive area between the top cover 10 and the explosion-proof film 20 is widened, the physical internal resistance is reduced structurally, and the conductive ability of the cap is enhanced.

[0026] Specifically, a bent edge 203 that bends towards the top cover 10 is formed on the outer edge of the explosion-proof film 20. The bent edge 203 wraps around the periphery of the top cover 10, that is, the bent edge 203 wraps around the periphery of the upper cover plate 101; the connection between the bent edge 203 and the upper cover plate 101 is laser welded to realize the electrical connection between the explosion-proof film 20 and the top cover 10. It can be understood that since the bent edge 203 is arranged to wrap around the periphery of the top cover 10, the radius size of the top cover 10 is smaller than that of the explosion-proof film 20.

[0027] Specifically, the material of the top cover 10 is steel, and the material of the explosion-proof film 20 is aluminum; of course, other conductive materials can also be selected.

[0028] Further, the explosion-proof area 201 is circular and is directly opposite to the upper top plate 102; of course, the shape of the explosion-proof area 201 can also be other shapes.

[0029] Further, the filling area 202 is located between the explosion-proof area 201 and the welding points of the top cover 10 and the explosion-proof film 20, that is, between the explosion-proof area 201 and the bent edge 203; the filling area 202 can be annular; refer to Figure 1 , it can be understood that the top cover 10 and the explosion-proof film 20 are both circular plate-shaped as a whole, and the annular filling area 202 can increase the contact area between the top cover 10 and the explosion-proof film 20, which is convenient for electrical conduction between the top cover 10 and the explosion-proof film 20.

[0030] Furthermore, the conductive member 30 is a metal conductive adhesive. It should be noted that the conductive adhesive is an adhesive having a certain conductivity after curing or drying, and it can connect a variety of conductive materials together to form an electrical path between the connected materials.

[0031] Specifically, the upper top plate 102 includes a connecting portion 1021 and an abutting portion 1022, wherein the connecting portion 1021 is located between the upper cover plate 101 and the abutting portion 1022; the pressure relief hole 103 is arranged at the connecting portion 1021, and a plurality of pressure relief holes 103 are arranged at intervals around the abutting portion 1022; the connecting portion 1021 is used to support the abutting portion 1022; it can be understood that since the top cover 10 and the explosion-proof plate 20 are connected through the conductive member 30, and the pressure relief hole 103 is arranged facing the explosion-proof area 201, the size of the upper top plate 102 should be smaller than the explosion-proof area 201.

[0032] Furthermore, an explosion-proof score line 204 is provided on one side of the explosion-proof sheet 20 away from the top cover 10, and the explosion-proof score line 204 is the outer edge line of the explosion-proof area 201. When the internal pressure of the battery is too high, the explosion-proof area 201 bursts along the explosion-proof score line 204, allowing the pressure relief hole 103 to ventilate, thereby discharging the high-temperature and high-pressure gas inside the battery to protect the battery safety.

[0033] This embodiment further provides a lithium battery, including a steel shell, a winding core disposed in the steel shell, and the above-mentioned cap structure 100 capable of enhancing the current flow capacity.

[0034] In summary, the utility model provides a cap structure 100 capable of enhancing the flow capacity, comprising a top cover 10 and an explosion-proof disc 20, wherein the explosion-proof disc 20 is coated on the periphery of the top cover 10 and connected to the top cover 10 by welding; an upper cover plate 101 protruding in a direction away from the explosion-proof disc 20 is provided in the middle of the top cover 10, and a plurality of pressure relief holes 103 penetrating the top cover 10 are arranged at intervals on the upper cover plate 101; an explosion-proof area 201 corresponding to the position of the upper cover plate 101 is arranged on the explosion-proof disc 20, a filling area 202 is arranged on the outer side of the explosion-proof area 201, and a conductive member 30 is arranged on the side of the filling area 202 close to the explosion-proof disc 20; by arranging the conductive member 30, the present application increases the contact area between the top cover 10 and the explosion-proof disc 20 on the basis of welding the top cover 10 and the explosion-proof disc 20, reduces the physical internal resistance, and thereby enhances the conductivity of the cap.

[0035] The present utility model is not limited only to what is described in the specification and embodiments. Therefore, additional advantages and modifications can be easily achieved by those skilled in the art. Thus, without departing from the spirit and scope of the general concept defined by the claims and their equivalents, the present utility model is not limited to the specific details, representative devices, and illustrative examples shown and described herein.

Claims

1. A cap structure capable of enhancing the flow capacity, characterized in that: It includes a top cover and an explosion-proof plate, wherein the top cover is adjacent to the explosion-proof plate and connected to the explosion-proof plate by welding; the top cover includes an upper cover plate and an upper top plate connected to the upper cover plate, and the upper top plate is provided with a protrusion in a direction away from the explosion-proof plate; a plurality of pressure relief holes are arranged at intervals on the upper top plate; the explosion-proof plate is provided with an explosion-proof area and a filling area arranged around the explosion-proof area, and the pressure relief hole passes through the upper top plate and faces the explosion-proof area; a conductive member is arranged on one side of the filling area close to the top cover, and the conductive member is used to connect the top cover and the explosion-proof plate to enhance the electrical conduction area between the top cover and the explosion-proof plate.

2. The cap structure capable of enhancing the flow capacity according to claim 1, characterized in that: The circumferential side of the explosion-proof plate is formed with a curved edge, and the curved edge is covered on the circumferential edge of the top cover; the connection between the curved edge and the upper cover plate is laser welded to achieve electrical connection between the explosion-proof plate and the top cover.

3. The cap structure capable of enhancing the flow capacity according to claim 2, characterized in that: The explosion-proof area is circular and is located directly opposite to the upper top plate.

4. The cap structure capable of enhancing the flow capacity according to claim 2, characterized in that: The filling area is located between the explosion-proof area and the bent edge; the filling area is in a circular shape.

5. The cap structure capable of enhancing the flow capacity according to claim 1, characterized in that: The conductive member is a metal conductive adhesive.

6. The cap structure capable of enhancing the flow capacity according to claim 1, characterized in that: The upper top plate includes a connecting portion and an abutting portion, wherein the connecting portion is located between the upper cover plate and the abutting portion; the pressure relief hole is arranged at the connecting portion, and a plurality of the pressure relief holes are arranged at intervals around the abutting portion.

7. The cap structure capable of enhancing flow capacity according to claim 1, characterized in that: The explosion-proof sheet is provided with an explosion-proof score line in a direction away from the top cover, and the explosion-proof score line is the outer edge line of the explosion-proof area.

8. A lithium battery, comprising a steel shell and a winding core disposed in the steel shell, characterized in that: The invention comprises a cap structure capable of enhancing the flow capacity as described in any one of claims 1 to 7.

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