Positive terminal and battery monomer

Abstract

The utility model relates to a cylindrical lithium secondary battery structure, in particular to a positive terminal and a battery monomer, the positive terminal comprises a positive current collector and a combined cap, and a positive current collector plate and a connecting aluminum sheet originally belonging to the combined cap are made into an integrated structure so as to form the positive current collector; according to the combined cap, the phenomenon of poor welding when the positive collector plate is connected with the combined cap can be avoided, an insulation structure is arranged on the positive collector plate, the bent part of the positive collector plate is bent towards the positive collector plate, the insulation structure plays an insulation role between the positive collector plate and the bent part, and a positive insulation pad is arranged on the connecting aluminum sheet, so that the positive collector plate can be connected with the combined cap. When the connecting aluminum sheet and the bending part are relatively bent, the positive electrode insulating pad plays an insulating role between the bending part and the connecting aluminum sheet; the battery monomer comprises a negative terminal, a battery pole group and the positive terminal.

Description

Technical Field

[0001] This utility model relates to a cylindrical lithium secondary battery structure, specifically to a positive terminal and a battery cell. Background Technology

[0002] The ever-increasing demand for energy is driving the development of the lithium battery industry. Performance requirements for lithium batteries are becoming increasingly stringent. Cylindrical, all-tab lithium-ion batteries are gaining popularity due to their advantages such as good rate performance, low cost, good safety, and high production efficiency. However, the current manufacturing process for all-tab lithium batteries involves numerous structural components, and these components are mostly connected by welding, a method whose stability still needs improvement.

[0003] For cylindrical all-tab lithium-ion batteries, the assembly of numerous structural components is cumbersome. In order to reduce the number of structural components, reduce production anomalies, and improve production efficiency, it is necessary to make new improvements to the structural components. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a positive terminal and a battery cell using the positive terminal, thereby adjusting the structure of the positive terminal, eliminating the existing process of welding the positive current collector and combining the cap, avoiding defects such as poor welding and solder joint detachment, and improving structural stability.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: a positive terminal, including a combined cap and a positive current collector, the positive current collector including a positive current collector plate and a connecting aluminum plate, the connecting aluminum plate being connected to the positive current collector plate and the connecting aluminum plate and the positive current collector plate being an integral structure, the connecting aluminum plate being connected to the explosion-proof aluminum plate of the combined cap, and the end face of the positive current collector plate facing away from the electrode group being provided with an insulating structure. The positive current collector plate and the connecting aluminum plate form an integral positive current collector and are linked to the combined cap, which can avoid poor welding when connecting the positive current collector plate and the combined cap.

[0006] As an optional solution, the outer edge of the positive current collector is provided with a bending part, and the connecting aluminum sheet is connected to the bending part. The connecting aluminum sheet, the bending part and the positive current collector are integrated into one structure.

[0007] As an optional solution, a positive insulating pad is provided on the end face of the connecting aluminum sheet facing away from the explosion-proof aluminum sheet. When the connecting aluminum sheet is bent toward the bending part, the positive insulating pad is located between the connecting aluminum sheet and the bending part.

[0008] As an optional solution, the insulation structure is insulating paper or insulating adhesive. When the bent part is bent toward the end face of the positive current collector away from the electrode group, the insulation structure is located between the bent part and the positive current collector.

[0009] Based on the same concept, this utility model also provides a battery cell, including a battery electrode assembly, a negative terminal, and a positive terminal.

[0010] Compared with the prior art, the advantages of this utility model are as follows: 1. By combining the connecting aluminum sheet of the positive current collector and the combined cap into one to form the positive current collector, the poor welding of the positive current collector and the combined cap in the conventional structure can be avoided, resulting in better stability; 2. The structure of the positive terminal can reduce one component of the battery, and by combining the separate positive insulating pad and the combined cap together, the production process of the battery can be significantly reduced, thereby improving the production efficiency of the battery; 3. The stable structure of the positive terminal can provide better assurance during the use of the battery and during relevant safety tests. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a cross-sectional schematic diagram of a single battery cell;

[0013] Figure 2 for Figure 1 Schematic diagram of the neutral extreme point;

[0014] Figure 3 This is a schematic diagram of the positive terminal.

[0015] Figure 4 A schematic cross-sectional view of the positive terminal;

[0016] In the diagram: 1. Positive terminal, 11. Combined cap, 111. Explosion-proof aluminum sheet, 112. Positive steel cap, 113. Insulating washer, 114. Sealing ring, 12. Positive current collector, 121. Positive current collector plate, 122. Connecting aluminum sheet, 123. Positive insulating pad, 2. Battery terminal assembly, 3. Negative terminal. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] Example 1

[0019] Please see Figures 1-4 A positive terminal includes a combined cap 11 and a positive current collector 12. The combined cap 11 is a prior art product and includes an explosion-proof aluminum sheet 111, a positive steel cap 112, an insulating washer 113, and a sealing ring 114. The explosion-proof aluminum sheet 111 and the positive steel cap 112 are disposed within the sealing ring 114, connected, and both mate with the sealing ring 114. The insulating washer 113 is disposed within the sealing ring 114 and mates with the explosion-proof aluminum sheet 111. The positive current collector 12 includes a positive current collector disk 121 and a connecting aluminum sheet 122. The positive current collector disk 121 is a prior art product, connected to the connecting aluminum sheet 122, and the two are an integral structure. The connecting aluminum sheet 122 is connected to the explosion-proof aluminum sheet 111 of the combined cap 11.

[0020] The positive current collector 121 and the connecting aluminum sheet 122, which originally belonged to the combined cap 11, are made into an integrated structure. Compared with the existing positive terminal, the two structural components are combined into one to form the positive current collector 12, thereby reducing one welding process. This not only improves the structural stability, but also avoids poor contact caused by incomplete welding, solder joint detachment, etc.

[0021] The positive current collector 121 has an insulating structure on the end face of the back electrode group. The insulating structure can be an attached insulating paper or insulating adhesive, which can also serve as insulation without affecting laser welding.

[0022] The positive current collector 121 has a bent portion on its exterior, and the connecting aluminum sheet 122 is connected to the bent portion. The connecting aluminum sheet 122, the bent portion, and the positive current collector 121 are an integral structure.

[0023] When the positive terminal is used in a battery, the connecting aluminum sheet 122 is connected to the explosion-proof aluminum sheet 111. The connecting aluminum sheet 122 is bent relative to the bent portion and the bent portion is bent relative to the positive current collector 121. The positive current collector 12 is Z-shaped. The positive insulating pad 123 is located between the connecting aluminum sheet 122 and the bent portion, and the insulating structure is located between the bent portion and the positive current collector 121. Moreover, the bent positive current collector 12 is also completely covered within the sealing ring 114, which can better protect the positive current collector 12. In the event of battery deformation, it can avoid contact with the steel shell, which is the negative terminal, preventing the risk of short circuit and improving safety.

[0024] Example 2

[0025] Please see Figure 1 and Figure 2 A battery cell, comprising a battery electrode assembly 2, a negative terminal 3, and a positive terminal 1 as described in Example 1.

[0026] The connecting aluminum sheet 122 in the positive terminal 1 is integrated with the positive current collector 121, reducing one structural component and thus lowering the probability of poor contact caused by welding and other processes. The positive current collector 121 is then welded to the positive terminal of the flattened tab assembly. The positive terminal and the positive terminal of the tab assembly together form the positive electrode of the battery. The negative terminal 3 uses a steel casing, which is welded to the negative current collector and then to the negative terminal of the flattened tab assembly, together forming the negative electrode of the battery.

[0027] Specifically, the size of the positive current collector 12 in the positive terminal 1 should be smaller than the minimum diameter of the steel shell. The thickness of the contact portion between the positive current collector 121 and the positive terminal of the electrode assembly should be controlled at approximately 0.2mm-0.6mm. Excessive thickness increases the difficulty of bending the positive current collector 121 and occupies too much space, affecting processes such as laser welding during battery assembly. Conversely, excessive thickness can lead to deformation of the positive current collector 121 under stress, thus affecting quality and performance. The positive current collector 121 should also have small holes with a diameter between 1mm and 3mm to facilitate sufficient electrolyte wetting of the electrode assembly and to facilitate venting after gas generation from the electrode assembly, preventing excessive expansion that could affect battery safety.

[0028] In this specification, the terms "an embodiment," "example," "specific example," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0029] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A positive electrode terminal comprising a combined cap (11), characterized in that: The positive electrode current collector (12) comprises a positive electrode current collecting disc (121) and a connecting aluminum sheet (122), the connecting aluminum sheet (122) is connected with the positive electrode current collecting disc (121) and the connecting aluminum sheet (122) is in an integral structure with the positive electrode current collecting disc (121), the connecting aluminum sheet (122) is connected with the explosion-proof aluminum sheet (111) of the combined cover (11), and the positive electrode current collecting disc (121) is provided with an insulating structure on the end face facing away from the pole group.

2. The positive terminal of claim 1, wherein: The outer edge of the positive electrode current collecting disc (121) is provided with a bending part, the connecting aluminum sheet (122) is connected with the bending part, and the connecting aluminum sheet (122), the bending part and the positive electrode current collecting disc (121) are in an integral structure.

3. The positive terminal of claim 2, wherein: The end face of the connecting aluminum sheet (122) facing away from the explosion-proof aluminum sheet (111) is provided with a positive electrode insulating pad (123), and the positive electrode insulating pad (123) is located between the connecting aluminum sheet (122) and the bending part when the connecting aluminum sheet (122) is bent towards the bending part.

4. The positive terminal of claim 2, wherein: The insulating structure is insulating adhesive paper or insulating adhesive, and the insulating structure is located between the bending part and the positive electrode current collecting disc (121) when the bending part is bent towards the end face of the positive electrode current collecting disc (121) facing away from the pole group.

5. A battery cell characterized by: The battery pole group (2), the negative electrode terminal (3) and the positive electrode terminal (1) of any one of claims 1-4 are comprised.

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