Welding structure of battery, battery, battery pack and electric equipment

Abstract

The utility model relates to a welding structure of a battery, the battery, a battery pack and electric equipment. The welding structure of the battery comprises a pole core and a transition sheet, a plurality of layers of tabs extend out of the end part of the pole core, the transition sheet is positioned on one side of the plurality of layers of tabs, a first welding printing area and a second welding printing area are arranged on the transition sheet, the first welding printing area is used for being connected with the plurality of layers of tabs in a welding manner, and the second welding printing area is used for being connected with a cover plate assembly of the battery in a welding manner; the first welding and printing area is provided with a first salient point structure, and when the transition piece and the tabs are welded and connected through the first welding and printing area, the first salient point structure can pierce and be connected with the multiple layers of tabs. According to the battery welding structure provided by the utility model, the welding process of the multi-layer tabs and the cover plate assembly can be simplified, and the welding quality can be ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of battery production and manufacturing, and more specifically, to a battery welding structure, a battery, a battery pack and an electrical device. Background Art

[0002] In battery production, a current collector made of aluminum foil or composite foil is arranged inside the pole core, and the current collector is usually wound or stacked at the end of the pole core to form a multi-layer pole ear. When the multi-layer pole ear is connected to the cover plate assembly, the ordinary ultrasonic welding mode is usually unable to achieve the one-time welding forming of the multi-layer composite foil, resulting in complicated overall process, reduced comprehensive one-time yield and increased cost. Utility Model Content

[0003] An object of the present invention is to provide a battery welding structure, a battery, a battery pack and an electrical device to solve at least one of the problems of the background technology.

[0004] According to a first aspect of the utility model, a battery welding structure is provided, comprising: a pole core and a transition sheet;

[0005] A plurality of layers of pole ears extend from the end of the pole core, the transition piece is located at one side of the plurality of layers of the pole ears, and a first weld print area and a second weld print area are provided on the transition piece, the first weld print area is used for welding and connecting with the plurality of layers of the pole ears, and the second weld print area is used for welding and connecting with the cover plate assembly of the battery;

[0006] The first weld print area is provided with a first convex point structure. When the transition piece and the pole lug are connected by welding through the first weld print area, the first convex point structure can pierce and connect multiple layers of the pole lug.

[0007] Optionally, the first weld print area is connected to the multiple layers of the pole tabs by ultrasonic welding to form an ultrasonic welded portion, and the second weld print area can be connected to the cover plate assembly by laser welding to form a laser welded portion.

[0008] Optionally, each layer of the tab includes an insulating layer and a first conductive layer and a second conductive layer arranged on both sides of the insulating layer, and the first bump structure can pierce the insulating layer, the first conductive layer and the second conductive layer to connect the first conductive layer with the second conductive layer.

[0009] Optionally, a plurality of the first bump structures are provided.

[0010] Optionally, a plurality of the first convex point structures are evenly distributed in the first soldering area in a dot matrix form.

[0011] Optionally, the arrangement range of the plurality of first bump structures accounts for greater than or equal to 50% of the area of ​​the first weld print region.

[0012] Optionally, the first bump structure is in the shape of a cone, a pyramid or a cylinder.

[0013] Optionally, the height of the first bump structure is greater than or equal to the total thickness of the multiple layers of the tabs.

[0014] Optionally, a protective sheet is further included, which is located at the other side of the multi-layer pole ear and corresponds to the position of the first weld print area.

[0015] Optionally, the area of ​​the protection sheet is smaller than the area of ​​the tab and larger than the area of ​​the first weld print area.

[0016] Optionally, a plurality of second convex point structures are provided on the protection sheet, and when the transition sheet and the pole lug are connected by welding through the first welding print area, the second convex point structures can also pierce and connect multiple layers of the pole lug.

[0017] Optionally, projections of the plurality of first bump structures and the plurality of second bump structures are interlaced, and the height of the second bump structures is less than or equal to the height of the first bump structures.

[0018] Optionally, the cover plate assembly is further included, and the cover plate assembly includes a pole, an insulating member and a light cover plate stacked in sequence, the pole is welded to the transition piece through the second weld print area, and the light cover plate is used to connect to the battery shell.

[0019] According to a second aspect of the present invention, a battery is provided, comprising the welding structure described in the first aspect.

[0020] According to a third aspect of the utility model, a battery pack is provided, comprising the battery described in the second aspect.

[0021] According to a fourth aspect of the present invention, there is provided an electrical device comprising the battery pack described in the third aspect.

[0022] One technical effect of the utility model is that, by arranging the first convex point structure in the first weld print area, the multi-layer pole ear can be completely connected with the transition plate through the piercing effect of the first convex point structure through only one welding process, which simplifies the welding process in the process of connecting the pole ear and the cover plate assembly and improves the welding quality of the battery.

[0023] Other features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which constitute a part of the specification, illustrate embodiments of the present utility model and, together with the description, are used to explain the principles of the present utility model.

[0025] Figure 1 The utility model is a schematic diagram of a welding structure of a battery.

[0026] Figure 2 yes Figure 1 CC section view.

[0027] Figure 3 yes Figure 2 A partial enlarged view of point E in the middle.

[0028] Figure 4 yes Figure 3 Exploded diagram.

[0029] Figure 5 The utility model is a structural schematic diagram of a transition piece provided by the utility model.

[0030] Figure 6 It is a schematic diagram of the distribution of multiple first bump structures in the first soldering area.

[0031] Figure 7 is a schematic diagram of the first bump structure.

[0032] Description of reference numerals:

[0033] 1. Pole core; 2. Pole ear; 3. Transition piece; 31. First convex point structure; 4. Cover plate assembly; 41. Pole column; 42. Insulating member; 43. Light cover plate; 5. Protective sheet. DETAILED DESCRIPTION

[0034] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention.

[0035] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present invention, its application, or uses.

[0036] Techniques and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the techniques and equipment should be considered part of the specification.

[0037] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0038] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0039] like Figures 1 to 7 As shown, according to one aspect of the utility model, a welding structure of a battery is provided, comprising: a pole core 1 and a transition piece 3; a plurality of layers of pole lugs 2 extend from the end of the pole core 1, the transition piece 3 is located at one side of the plurality of layers of the pole lugs 2, and a first weld print area and a second weld print area are provided on the transition piece 3, the first weld print area is used for welding and connecting with the plurality of layers of the pole lugs 2, and the second weld print area is used for welding and connecting with the cover plate assembly 4 of the battery; the first weld print area is provided with a first convex point structure 31, and when the transition piece 3 and the pole lug 2 are welded and connected through the first weld print area, the first convex point structure 31 can pierce and connect the plurality of layers of the pole lugs 2.

[0040] Specifically, in battery production, a current collector made of aluminum foil or composite foil is arranged inside the pole core 1, and the current collector is usually wound or stacked at the end of the pole core 1 to form a multi-layer pole ear 2. When the multi-layer pole ear 2 is connected to the cover plate assembly 4, the ordinary ultrasonic welding mode cannot achieve one-time welding of the multi-layer composite foil. In this embodiment, by setting a first convex point structure 31 in the first welding area of ​​the transition sheet 3, when the pole ear 2 is welded to the transition sheet 3, the first convex point structure 31 can pierce the multi-layer pole ear 2, so that only one welding is required to achieve the conductive connection between the multi-layer pole ear 2 and the transition sheet 3, and subsequently only the transition sheet 3 needs to be welded to the cover plate assembly 4 to achieve the conductive connection between the pole ear 2 and the cover plate assembly 4. Among them, the transition sheet 3 is usually made of a conductive material, usually a copper plate or an aluminum plate, which plays a role in diversion.

[0041] The welding structure of the above-mentioned battery provided in this embodiment realizes the direct welding connection between the multi-layer pole ear 2 and the transition plate 3 through the special design of the first convex point structure 31, thereby reducing the number of welding times when the multi-layer pole ear 2 is connected to the transition plate 3. On the one hand, it avoids the problems such as high risk of cold welding, large ohmic impedance, and more metal debris caused by too many welding times, thereby improving the production yield and safety performance of the battery. On the other hand, it reduces the equipment investment, improves the production efficiency, and reduces the investment cost.

[0042] In this embodiment, the first weld print area and the second weld print area can be set according to actual needs, that is, they can be planned according to parameters such as the size of the pole ear 2 and the transition piece 3. They can be distributed on the same side of the transition piece 3 or on both sides of the transition piece 3. When distributed on both sides of the transition piece 3, they can be staggered or overlapped. It can be determined specifically according to the connection position of the pole ear 2 and the cover plate assembly 4 on the transition piece 3. The utility model does not limit this. In addition, the first bump structure 31 can pierce the multi-layer pole ear 2 during the welding process. Each layer of the pole ear 2 can be a single-layer foil or a multi-layer composite foil. The range, shape, size and other parameters of the first bump structure 31 can be designed according to actual needs.

[0043] Optionally, the first weld print area is connected to the multiple layers of the pole lugs 2 by ultrasonic welding to form an ultrasonic welded portion, and the second weld print area can be connected to the cover plate assembly 4 by laser welding to form a laser welded portion.

[0044] Specifically, ultrasonic welding is a welding technology that uses high-frequency vibration waves to transmit to the surfaces of two objects to be welded together, and then rubs them to form a fusion between the objects. Ultrasonic welding of the multi-layer tab 2 and the transition sheet 3 to form an ultrasonic weld has the advantages of being fast, efficient, energy-saving, and environmentally friendly.

[0045] Laser welding is an efficient and precise welding method. It uses a high-energy-density laser beam as a heat source and focuses the laser beam on the welding point through optical focusing, so that the metal surface is quickly heated and melted to achieve material connection. Laser welding is used to weld the transition piece 3 and the cover plate assembly 4 to form a laser welding part, which has the advantages of high energy density, small penetration, small deformation, high weld quality, wide applicability and high degree of automation.

[0046] Optionally, each layer of the tab 2 includes an insulating layer and a first conductive layer and a second conductive layer arranged on both sides of the insulating layer, and the first bump structure 31 can pierce the insulating layer, the first conductive layer and the second conductive layer to connect the first conductive layer with the second conductive layer.

[0047] Specifically, in this embodiment, the current collector of the pole core 1 is made of a composite foil, so that each layer of the multi-layer pole tab 2 is also a composite foil, for example, composed of PET / PP material + upper and lower thin layers of metal, forming a middle insulating layer plus two conductive layers. PET / PP material has the characteristics of insulation, lower melting point, lower density, etc., which can meet the battery's pursuit of higher safety and higher energy density, but the multi-layer composite foil also has a welding bottleneck. Due to the setting of the middle insulating layer, the ordinary ultrasonic welding mode cannot achieve one-time welding of the multi-layer composite foil.

[0048] In this embodiment, since the first protrusion structure 31 can pierce the multi-layer pole ear 2, the conductive layer of each layer of the pole ear 2 can be mutually connected through the first protrusion structure 31. On the premise of simplifying the connection process of the multi-layer pole ear 2 and the cover plate assembly 4, the advantages of the battery with a current collector made of a composite foil material are also guaranteed, so that each layer of the pole ear 2 can be welded to the pole ear 2 and the transition plate 3 of a composite copper foil, a composite aluminum foil or the like within 10 to 150 layers without cracking or breaking.

[0049] The above welding process can be carried out according to the following process: first load and position the pole core 1, and then load and position the current collector made of multi-layer composite foil and the transition piece 3 respectively after positioning. If a protective sheet 5 (for protecting the pole ear 2) is provided, loading and positioning can also be carried out at the same time. After the above components are assembled, they are moved to the welding position as a whole, and contact, pressing and positioning are performed. After completion, the welding machine receives a trigger welding signal, so that the welding energy is completed, a complete weld is formed, and the pole ear 2 and the transition piece 3 are welded and connected. Then the cover plate assembly 4 is loaded and positioned, and the welding of the transition piece 3 and the cover plate assembly 4 (pole 41) is completed, and a battery cell can be completed.

[0050] Alternatively, if Figures 5 and 6 As shown, a plurality of first bump structures 31 are provided.

[0051] Specifically, in this embodiment, a plurality of first bump structures 31 are distributed in the first weld print area, so that during the welding process, the plurality of first bump structures 31 can pierce the multi-layer tab 2, thereby ensuring the welding quality and improving the reliability of the welding connection.

[0052] Alternatively, if Figures 5 and 6 As shown, a plurality of the first bump structures 31 are evenly distributed in the first soldering area in a dot matrix form.

[0053] Specifically, in this embodiment, the plurality of first convex point structures 31 are evenly distributed in a dot matrix form, which can make the connection of the multi-layer tab 2 more stable and reliable. Among them, the plurality of first convex point structures 31 can be an equidistant array or an unequally spaced array. The first weld print area is usually circular, elliptical, racetrack-shaped, etc. The first convex point structure 31 can be matched and set according to the shape and size of the first weld print area, and the utility model does not limit this.

[0054] For example, in one embodiment, the width of the first weld print area (reference Figure 6 A) in the range is 0.05~20.0mm; length (reference Figure 6 The range of B) is 0.05 to 100 mm, then the distribution array spacing of the first bump structure 31 (reference Figure 6The d1 and d2 in the figure can be designed to be 0 to 20 mm, and the diameter or width of the first bump structure 31 (refer to Figure 6 The range of D) is 0.05 to 5.0 mm. Figure 6 , the arrangement range of the plurality of first bump structures 31 accounts for greater than or equal to 50% of the area of ​​the first welding print area.

[0055] Specifically, in this embodiment, by limiting the arrangement range of the first bump structure 31, the arrangement range of the first bump structure 31 is not less than 50%, thereby ensuring the material stripping weld core residual rate of the multi-layer tab 2 after welding, further ensuring the welding connection quality between the tab 2 and the transition piece 3, and improving the reliability of the connection conduction.

[0056] Optionally, refer to Figure 5 or Figure 7 The first bump structure 31 is in the shape of a cone, a pyramid or a cylinder.

[0057] Specifically, in order to facilitate the first bump structure 31 to smoothly pierce the multi-layer pole ear 2 during the welding process, the shape of the first bump structure 31 is designed to be a cone, a pyramid, a cylinder, a rectangular cube or an irregular sharp object shape to improve the reliability of the conduction between the multi-layer pole ear 2 and the transition piece 3.

[0058] Optionally, refer to Figure 7 , the height of the first bump structure 31 ( Figure 7 The H) is greater than or equal to the total thickness of the multiple layers of the pole ear 2.

[0059] Specifically, in this embodiment, in order to ensure that the first bump structure 31 can completely pierce all the tabs 2, the height of the first bump structure 31 is set to be slightly greater than or equal to the total thickness of the multilayer tabs 2. Generally, the height of the first bump structure 31 can be set to 0.05-2.0 mm.

[0060] Optionally, refer to Figure 3 or Figure 4 The welding structure of the battery further includes a protective sheet 5, which is located at the other side of the multi-layered pole lug 2 and corresponds to the position of the first weld print area.

[0061] Specifically, in order to prevent the tab 2 from being scratched by welding slag or the like during welding, the battery welding structure in this embodiment is provided with a protective sheet 5 which can be made of a copper sheet or an aluminum sheet or the like.

[0062] Optionally, refer to Figure 3 or Figure 4 The area of ​​the protection sheet 5 is smaller than the area of ​​the tab 2 and larger than the area of ​​the first weld print area.

[0063] Specifically, in this embodiment, the size of the protection sheet 5 is designed to be smaller than the size of the pole tab 2 and larger than the size of the first weld print area, so that while protecting the pole tab 2, it can also prevent it from occupying too much space inside the battery.

[0064] Optionally, a plurality of second bump structures are provided on the protection sheet 5 , and when the transition sheet 3 and the pole lug 2 are connected by welding through the first weld print area, the second bump structures can also pierce and connect multiple layers of the pole lug 2 .

[0065] Specifically, in this embodiment, a second bump structure may also be provided on the protective sheet 5, and its structural setting range and shape may be the same as those of the first bump structure 31, so that in the actual welding process, both the first bump structure 31 and the second bump structure can pierce the multi-layer pole ear 2, further improving the reliability of welding.

[0066] Optionally, projections of the plurality of first bump structures 31 and the plurality of second bump structures are staggered, and the height of the second bump structures is less than or equal to the height of the first bump structures 31 .

[0067] Specifically, in this embodiment, multiple first bump structures 31 and multiple second bump structures are arranged alternately, and the height of the second bump structure is less than or equal to the height of the first bump structure 31, which can improve the tightness of the pressing of the multi-layer pole tabs 2 on the basis of achieving reliable welding connection, thereby improving battery performance.

[0068] Optionally, refer to Figure 3 or Figure 4 The welding structure of the battery also includes the cover plate assembly 4, which includes a pole 41, an insulating member 42 and a light cover plate 43 stacked in sequence, the pole 41 is welded to the transition piece 3 through the second weld print area, and the light cover plate 43 is used to be connected to the battery shell.

[0069] Specifically, in this embodiment, the pole 41 in the cover plate assembly 4 is connected to the transition sheet 3 through the second weld print area, so that the pole ear 2 and the pole 41 are connected to each other, and the battery can be charged and discharged externally. Among them, the welding of the cover plate assembly 4 and the second weld print area can be realized by a new resistance welding method, so that the heat input of the welding is smaller, and the insulation distance between the bare cover plate 43 and the insulation sheet can be designed to be smaller, for example, 0.05 to 2.0 mm. Figure 1 to Figure 2 .

[0070] According to a second aspect of the present invention, a battery is provided, comprising the welding structure described in the first aspect.

[0071] Specifically, in this embodiment, a battery is provided which is produced by the welding structure described in the first aspect. Since there are fewer welding steps in its production, the production efficiency is improved, the equipment cost is reduced, and the battery quality is improved.

[0072] According to a third aspect of the utility model, a battery pack is provided, comprising the battery described in the second aspect.

[0073] Specifically, the battery pack composed of the batteries provided in the second aspect has higher safety performance and a shorter production cycle, and is suitable for use in large-scale electrical equipment.

[0074] According to a fourth aspect of the utility model, there is provided an electrical device, comprising the battery pack described in the third aspect.

[0075] Specifically, in this embodiment, the electrical equipment uses the battery pack provided by the third aspect as an energy source, thereby improving the safety of the electrical equipment.

[0076] The above embodiments focus on the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Considering the simplicity of the text, they will not be repeated here.

[0077] Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A welding structure of a battery, characterized in that: include: Pole core and transition piece; A plurality of layers of pole ears extend from the end of the pole core, the transition piece is located at one side of the plurality of layers of the pole ears, and a first weld print area and a second weld print area are provided on the transition piece, the first weld print area is used for welding and connecting with the plurality of layers of the pole ears, and the second weld print area is used for welding and connecting with the cover plate assembly of the battery; The first weld print area is provided with a first convex point structure. When the transition piece and the pole lug are connected by welding through the first weld print area, the first convex point structure can pierce and connect multiple layers of the pole lug.

2. The welding structure of the battery according to claim 1, characterized in that: The first weld print area is connected to the multiple layers of the pole tabs by ultrasonic welding to form an ultrasonic welded portion, and the second weld print area can be connected to the cover plate assembly by laser welding to form a laser welded portion.

3. The welding structure of a battery according to claim 1, characterized in that: Each layer of the tabs includes an insulating layer and a first conductive layer and a second conductive layer arranged on both sides of the insulating layer. The first bump structure can pierce the insulating layer, the first conductive layer and the second conductive layer to connect the first conductive layer with the second conductive layer.

4. The welding structure of a battery according to claim 1, characterized in that: A plurality of the first bump structures are provided.

5. The welding structure of the battery according to claim 4, characterized in that: The plurality of first convex point structures are evenly distributed in the first soldering area in a dot matrix form.

6. The welding structure of a battery according to claim 4, characterized in that: The arrangement range of the plurality of first bump structures accounts for greater than or equal to 50% of the area of ​​the first weld print region.

7. The welding structure of a battery according to claim 1, characterized in that: The first convex point structure has a shape of a cone, a pyramid or a cylinder.

8. The welding structure of a battery according to claim 1, characterized in that: The height of the first bump structure is greater than or equal to the total thickness of the multiple layers of the tabs.

9. The welding structure of a battery according to claim 1, characterized in that: A protection sheet is also included, which is located at the other side of the multi-layered pole ear and corresponds to the position of the first weld print area.

10. The welding structure of a battery according to claim 9, characterized in that: The area of ​​the protection sheet is smaller than the area of ​​the tab and larger than the area of ​​the first weld print area.

11. The welding structure of a battery according to claim 9, characterized in that: A plurality of second convex point structures are arranged on the protection sheet. When the transition sheet and the pole lug are connected by welding through the first welding print area, the second convex point structures can also pierce and connect multiple layers of the pole lug.

12. The welding structure of a battery according to claim 11, characterized in that: Projections of the plurality of first bump structures and the plurality of second bump structures are interlaced, and the height of the second bump structures is less than or equal to the height of the first bump structures.

13. The welding structure of a battery according to claim 1, characterized in that: It also includes the cover plate assembly, which includes a pole, an insulating member and a light cover plate stacked in sequence, the pole is welded to the transition piece through the second weld print area, and the light cover plate is used to connect to the battery shell.

14. A battery, characterized in that: A welding structure comprising any one of claims 1 to 13.

15. A battery pack, characterized in that: Comprising the battery of claim 14.

16. An electrical equipment, characterized in that: Includes the battery pack as claimed in claim 15.

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