Current collector, battery cell and power utilization device
Through the welding process of the all-pole ear technology optimized by the inclined imprinted boss and fluid channel, the laser welding difficulties caused by the multi-layer structure of the core electrode ear are solved, and efficient and stable welding effects are achieved, improving the overcurrent capability and safety of the battery cell.
Patent Information
- Application Number
- CN202422328408.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-23
- Publication Date
- 2025-09-05
- Estimated Expiration
- 2034-09-23
AI Technical Summary
In the existing all-pole ear technology, the multi-layer structure of the core ear leads to difficulty in laser penetration welding. The existing solutions have problems such as insufficient cutting accuracy, metal debris generation, and poor process stability, which affects welding quality and safety.
The inclined imprinting bosses are used to partially imprint the core ears to form orderly lodging, ensuring that the laser penetrates the plane required for welding, reducing welding gaps, and optimizing the welding process through fluid channels.
It improves the stability and quality of welding, reduces the welding defect rate, enhances the overcurrent capability and safety of the battery cell, and improves production efficiency and equipment adaptability.
Smart Images
Figure CN223309007U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of battery cell technology, and in particular to a current collector, a battery cell, and an electrical device. Background Art
[0002] Full-tab technology, also known as tab-free technology, is a key technology for improving the power and fast-charging performance of cylindrical battery cells. It is also an indispensable foundation for manufacturing large cylindrical battery cells. In traditional designs, cylindrical battery cells use a tab extending from the positive and negative poles of the winding core, and then connecting them to the top cover and the shell to serve as the current conduction path. However, this design is limited by the size of the tab, resulting in limited current capacity of the battery cell.
[0003] Full-tab technology revolutionizes this situation. It directly extracts the copper and aluminum foils on the positive and negative sides of the core from the core to form new tabs. The current collector is then welded to these tabs, and finally the collector is welded to the top cover (or pole) and the shell. This innovation greatly increases the contact area between the battery core, the pole, and the shell, significantly improving the cell's current capacity and reducing internal resistance, thereby achieving a leap in power and fast-charging performance for cylindrical cells.
[0004] In the welding process for full-tab technology, laser penetration welding is typically used to connect the collector plate and the tab. However, stable laser welding relies on a flat and close-contact welding interface. However, rolled tabs are typically made of wound metal foil, forming a multi-layer structure with uniform gaps. This structure is not conducive to the direct application of laser penetration welding, thus becoming a major challenge facing full-tab technology.
[0005] To solve this problem, there are currently three mainstream full-tab technology solutions:
[0006] 1. Cut and stack tabs: This method uses laser cutting technology to cut the tabs into strips and fold them uniformly toward the center of the core, forming a nearly flat welding surface. Laser welding is then performed through the collector plate. However, this method suffers from issues such as insufficient cutting accuracy, material dropout, the generation of melt beads, and compromised tab strength, impacting process stability and product performance.
[0007] 2. Flattening the tabs: This solution uses physical means to compress and flatten the tabs at both ends of the core, forming a flat surface for laser penetration welding. However, this method may generate metal debris during processing, increasing the risk of internal short circuits in the battery cell and posing a safety threat.
[0008] 3. Localized embossing: This approach maintains the tab's vertical position and creates an embossment on the tab through localized extrusion. This causes the tab at the bottom of the embossment to fall in an orderly manner, forming a nearly flat localized weld surface. While this approach avoids some of the drawbacks of the previous two approaches, in practice, the process is inefficient and unstable due to the fragile and easily deformed structure of the winding core tabs. Furthermore, the assembly sequence of the embossing and collector plates can result in gaps in the weld area, compromising weld quality and potentially damaging the winding core. Utility Model Content
[0009] The purpose of this application is to provide a current collector, a battery cell and an electrical device to solve the deficiencies in the prior art.
[0010] To achieve the above objectives, embodiments of the present application provide a current collector, comprising a current collector body and a stamping boss. One end surface of the current collector body serves as a mounting end surface; the stamping boss is disposed at the mounting end surface of the current collector body; the end surface of the stamping boss facing away from the current collector body serves as a stamping end surface; and the stamping end surface is disposed at an angle relative to the mounting end surface.
[0011] In one embodiment, the number of the embossing bosses is at least two, at least two of the embossing bosses are distributed along a first track on the mounting end surface, the first track is circular, and at least one of the embossing bosses has its length direction arranged along the radial direction of the first track.
[0012] In one embodiment, the stamping boss is inclined relative to the mounting end surface at a first preset angle α along the radial direction of the first track, wherein 0°<α≤35°.
[0013] In one embodiment, the stamping boss is a shell structure with a cavity inside, and the shell structure has an opening, and the opening is located on the welding end face on the current collecting part body, and the welding end face is on the current collecting part body and is in a relative position to the mounting end face; in the shell structure of the stamping boss, the shell wall where the stamping end face is located has a consistent wall thickness at all locations.
[0014] In one embodiment, a fluid channel is provided on the current collecting member body, the number of the fluid channel is at least one, and the outlet of the fluid channel is provided on the mounting end surface.
[0015] In one embodiment, the cross-section of the fluid channel in the radial direction is polygonal.
[0016] In one embodiment, a first through hole is formed on the current collecting member body along the central axis.
[0017] An embodiment of the present application also provides a battery cell, comprising a battery cell body and a current collecting member of any of the above embodiments. The battery cell body has pole tabs, and the pole tabs include a positive pole tab and a negative pole tab. Two current collecting members are provided, one current collecting member is provided on the positive pole tab, and the other current collecting member is provided on the negative pole tab.
[0018] In one embodiment, the radius of the battery cell body is R, and the length of the current collecting member along the radial direction of the battery cell body is r, wherein r≥0.3R.
[0019] An embodiment of the present application further provides an electrical device comprising a battery cell according to any of the above embodiments.
[0020] The above technical solution has at least the following beneficial effects: the current collector provided in the embodiment of the present application is used to imprint the pole tabs, the inclined imprinting end surface is used to directly imprint the pole tabs on the wound battery cell locally, and the pole tabs are orderly fallen down along a certain direction, thereby reducing the gap that may exist in the welding area between the current collector and the pole tabs, obtaining the plane required for laser penetration welding, and reducing poor welding.
[0021] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.
[0023] Figure 1 A schematic structural diagram of one embodiment of a current collecting member provided in an embodiment of the present application from one perspective;
[0024] Figure 2 A schematic structural diagram from two perspectives of one embodiment of a current collecting member provided in an embodiment of the present application;
[0025] Figure 3 A schematic structural diagram of another embodiment of a current collecting member provided in an embodiment of the present application from three perspectives;
[0026] Figure 4 A schematic structural diagram of another embodiment of a current collecting member provided in an embodiment of the present application from four perspectives;
[0027] Figure 5 This is a schematic diagram of the process of stamping the battery cell tab on the current collector in the prior art;
[0028] Figure 6A schematic diagram of the process of imprinting the cell tabs on the current collector provided in one embodiment of the present application;
[0029] Figure 7 A schematic structural diagram of one embodiment of the current collecting member provided in the embodiments of the present application from five perspectives;
[0030] Figure 8 This is a schematic structural diagram of six perspectives of another embodiment of the current collecting member provided in an embodiment of the present application.
[0031] icon:
[0032] 100 - current collecting member body; 110 - mounting end surface; 120 - fluid channel; 130 - first through hole;
[0033] 200-embossing boss; 210-embossing end face; 220-opening;
[0034] 300-Pole lug. DETAILED DESCRIPTION
[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.
[0036] In the description of this application, it should be noted that the terms "inner" and "outer" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or the orientations or positional relationships in which the product of this application is typically placed when in use. These terms are intended solely to facilitate the description of this application and simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" and the like are used solely for distinction and should not be construed as indicating or implying relative importance.
[0037] It should also be noted that, in the description of this application, unless otherwise expressly specified or limited, the terms "disposed" and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.
[0038] The embodiments of the present application provide a current collector, a battery cell and an electrical device. Figure 1As shown, in a first aspect, the current collecting member provided by the embodiment of the present application includes a current collecting member body 100 and an embossing boss 200 .
[0039] For example, Figure 1 As shown, the current collecting body 100 is a disc-shaped structure. However, in another embodiment, the current collecting body 100 is a polygonal plate structure, for example, the current collecting body 100 is a triangular plate structure, a quadrilateral plate structure, or a pentagonal plate structure.
[0040] One of the end faces of the current collecting member body 100 is a mounting end face 110, and the mounting end face 110 is used to fix the stamping boss 200. Figure 1 As shown, the stamping boss 200 is provided at the mounting end surface 110 on the current collecting body 100. For example, the stamping boss 200 is fixedly provided on the mounting end surface 110 of the current collecting body 100 by welding, clamping or integral molding. Figure 2 and Figure 4 As shown, for example, the one-piece forming method includes but is not limited to stamping, casting, etc.
[0041] The end surface of the stamping boss 200 away from the current collecting body 100 is the stamping end surface 210. Figure 6 As shown, the stamped end face 210 is used to stamp the tab 300 of the wound core battery cell, and then the stamped portion is welded by laser, brazing, etc., so that the stamped boss 200 and the tab 300 are fixedly connected, and then the current collector body 100 and the tab 300 are fixedly connected, and the current generated by the battery cell is transmitted to the outside through the current collector.
[0042] like Figure 1 or Figure 3 As shown, the stamping end surface 210 is tilted relative to the mounting end surface 110; Figure 5 As shown, using the current collecting piece in the prior art to stamp the tab 300 easily creates a gap between the current collecting piece and the tab 300, resulting in poor welding. Compared with the prior art, Figure 6 As shown, the current collecting piece provided in the embodiment of the present application is used to imprint the pole tab 300, and the pole tab 300 on the wound core cell is locally imprinted directly through the inclined imprinting end face 210, and the pole tab 300 is orderly fallen in a certain direction, thereby reducing the gap that may exist in the welding area between the current collecting piece and the pole tab 300, obtaining the plane required for laser penetration welding, and reducing poor welding.
[0043] like Figure 1 and Figure 3 As shown, in one embodiment, the number of the embossing bosses 200 is at least two, and at least two embossing bosses 200 are distributed along a first track on the mounting end surface 110. The first track is circular, and at least one embossing boss 200 is arranged with its length direction along the radial direction of the first track.
[0044] For example, the number of the embossing bosses 200 is two. In another embodiment, the number of the embossing bosses 200 is three. In another embodiment, the number of the embossing bosses 200 is four. In another embodiment, the number of the embossing bosses 200 is six.
[0045] By distributing the stamping bosses 200 along a circular trajectory, it is possible to ensure that the pressure or force applied in all directions is more uniform, which helps to improve the stability and reliability of the entire mechanical structure.
[0046] In one embodiment, the stamping boss 200 is tilted relative to the mounting end surface 110 along the radial direction of the first track at a first preset angle α, wherein 0°<α≤35°.
[0047] For example, the embossing boss 200 has two ends, an end of the embossing boss 200 close to the center of the first track is a first end, and an end of the embossing boss 200 away from the center of the first track is a second end. Figure 1 As shown, in some embodiments, the stamping boss 200 is tilted outward at a first preset angle α with the first end as the rotation center, wherein 0°<α≤35°, exemplarily, α=5°, in another embodiment, α=15°, in another embodiment, α=30°, and in another embodiment, α=35°.
[0048] like Figure 3 As shown, in some other embodiments, the stamping boss 200 is tilted outwardly with the second end as the rotation center to set a first preset angle α, where 0°<α≤35°. For example, α=5°, in another embodiment, α=15°, in another embodiment, α=30°, and in another embodiment, α=35°.
[0049] The inclined stamping boss 200 can generate a certain lateral force during the stamping process, which helps to better tilt the tab 300 in one direction, thereby optimizing the stamping effect and achieving the expected effect more accurately.
[0050] By adjusting the inclination angle α of the embossing boss 200 (0°<α≤35°), the contact angle and contact area between the embossing boss 200 and the material to be embossed can be precisely controlled during the embossing process. This adjustment helps achieve a more uniform embossing force distribution, thereby improving embossing accuracy and consistency.
[0051] Different materials and stamping requirements may require different contact angles. A range of 0° < α ≤ 35° allows for adaptability to a wide range of materials and processes without further adjustment of the α value, improving the adaptability, versatility, and flexibility of the current collector. A suitable tilt angle reduces direct friction between the stamping boss 200 and the material being stamped, lowering the risk of wear and damage. This helps extend the life of the mechanical structure and reduces the frequency of maintenance and component replacement.
[0052] Thanks to the precise control and adaptability of the 200° embossing boss, 0°<α≤35°, the equipment can be adjusted more quickly to meet different production needs, thereby improving production efficiency. At the same time, reducing rework and scrap caused by poor embossing also helps improve overall production efficiency and economic benefits.
[0053] like Figure 2 and Figure 4 As shown, in one embodiment, the stamped boss 200 is a shell structure with a cavity inside, and the shell structure has an opening 220. The opening 220 is located on the welding end face on the current collecting component body 100. The welding end face is the end face of the current collecting component body 100 and is in a relative position to the mounting end face 110. During the welding process, the welding laser welds the bottom of the opening 220 to fix the stamped boss 200 to the tab 300.
[0054] like Figure 4 As shown, in the shell structure of the stamping boss 200, the shell wall where the stamping end face 210 is located has a consistent wall thickness at all locations, and the error does not exceed ±0.05mm. Since the wall thickness of the shell wall where the stamping end face 210 is located is consistent at all locations, it can be ensured that during the stamping process, the contact area and pressure distribution between the stamping boss 200 and the material to be stamped are more uniform. This helps to improve the accuracy and consistency of stamping and reduce stamping quality problems caused by uneven wall thickness. For some processes that require stamping in a high-temperature environment, the wall thickness of the shell wall where the stamping end face 210 is located is consistent at all locations, which helps to optimize the heat conduction performance. Consistent wall thickness can reduce deformation or cracking problems caused by uneven thermal stress, and also helps to improve thermal efficiency and reduce energy consumption.
[0055] The design of the shell structure can increase the overall structural strength of the stamping boss 200, making it able to withstand greater pressure and impact. This strength improvement helps to ensure that the stamping boss 200 can remain stable and not easily deformed or damaged during the stamping process.
[0056] like Figure 8As shown, in one embodiment, a fluid channel 120 is provided on the current collector body 100. There is at least one fluid channel 120, and the outlet of the fluid channel 120 is provided on the mounting end surface 110. For example, the inlet of the fluid channel 120 is provided on the welding end surface. In another embodiment, the inlet of the fluid channel 120 is provided on the end surface of the current collector body 100. For example, when the current collector is welded to the tab 300 of the battery cell, electrolyte can be injected into the battery cell through the fluid channel 120, and gas generated when the battery cell loses control can be discharged through the fluid channel 120, thereby preventing gas accumulation inside the battery cell, resulting in increased pressure and potential safety issues. The more fluid channels 120 provided, the higher the electrolyte injection efficiency and gas discharge efficiency.
[0057] Illustratively, one fluid channel 120 is provided. In another embodiment, two fluid channels 120 are provided. In another embodiment, five fluid channels 120 are provided. In another embodiment, ten fluid channels 120 are provided.
[0058] like Figure 8 As shown, in one embodiment, the cross-section of the fluid channel 120 in the radial direction is polygonal. For example, the cross-section of the fluid channel 120 in the radial direction is an N-gon. When the number of sides N of the cross-section of the fluid channel 120 approaches infinity, its cross-sectional shape approaches a circle. In another embodiment, the cross-section of the fluid channel 120 in the radial direction is triangular. In another embodiment, the cross-section of the fluid channel 120 in the radial direction is a quadrilateral. In another embodiment, the cross-section of the fluid channel 120 in the radial direction is a fan-shaped. In another embodiment, the cross-section of the fluid channel 120 in the radial direction is a pentagon.
[0059] like Figure 7 and Figure 8 As shown, in one embodiment, a first through hole 130 is opened on the current collector body 100 along the central axis direction. When the current collector body 100 is assembled on the battery cell, the inner wall of the first through hole 130 can better limit the current collector body 100, thereby improving the coaxiality of the current collector body 100 and the battery cell, making the embossing marks on the tab 300 more uniform and axially symmetrical, which is conducive to subsequent welding.
[0060] In a second aspect, an embodiment of the present application provides a battery cell, comprising a battery cell body and a current collector as in any of the above embodiments, wherein the battery cell body has tabs, the tabs comprising a positive tab and a negative tab; two current collectors are provided, one current collector is provided on the positive tab, and the other current collector is provided on the negative tab.
[0061] Exemplarily, the material of the current collector located at the positive electrode of the battery cell body includes, but is not limited to: aluminum alloy, nickel-plated aluminum alloy, nickel, stainless steel (i.e., alloy steel containing nickel, molybdenum, titanium, niobium, copper, iron, etc.), or alumina. Exemplarily, the material of the current collector located at the negative electrode of the battery cell body includes, but is not limited to: copper, nickel-plated copper, stainless steel (i.e., alloy steel containing nickel, molybdenum, titanium, niobium, copper, iron, etc.), or nickel, etc.
[0062] In one embodiment, the radius of the battery cell body is R, and the length of the current collector along the radial direction of the battery cell body is r, where r≥0.3R. The increase in the length of the current collector means that its contact area with the active material inside the battery cell increases. This helps to collect current more efficiently, reduce resistance loss, and improve the overall performance of the battery. A longer current collector can shorten the current transmission path inside the battery cell, thereby reducing the internal resistance of the battery and improving the battery's charge and discharge efficiency. The current collector not only collects current but also has a certain supporting role. Properly increasing its length can enhance support for the internal structure of the battery cell and prevent structural damage caused by volume changes during charging and discharging. In application scenarios such as mobile devices or electric vehicles, the battery may be subjected to vibration or impact. A longer current collector can provide better shock resistance and protect the internal structure of the battery cell from damage.
[0063] In a third aspect, embodiments of the present application provide an electrical device comprising a battery cell according to any of the above embodiments. For example, the electrical device includes, but is not limited to, a motor, a lighting device, an electric heating device, a logic circuit board, or other electrical components (e.g., a resistor, a capacitor, etc.).
[0064] It should be noted that, unless there is any conflict, the features in the embodiments of this application can be combined with each other.
[0065] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.
Claims
1. A current collecting member, characterized in that: include: A current collecting component body (100), wherein one end surface of the current collecting component body (100) is a mounting end surface (110); A stamping boss (200) is provided at the mounting end surface (110) on the current collecting component body (100); the end surface of the stamping boss (200) on the side away from the current collecting component body (100) is a stamping end surface (210); and the stamping end surface (210) is arranged obliquely relative to the mounting end surface (110).
2. The current collecting member according to claim 1, characterized in that: The number of the embossing bosses (200) is at least two, and at least two of the embossing bosses (200) are distributed along a first track on the mounting end surface (110), the first track is circular, and the length direction of at least one of the embossing bosses (200) is arranged along the radial direction of the first track.
3. The current collecting member according to claim 2, characterized in that: The stamping boss (200) is inclined relative to the mounting end surface (110) at a first preset angle α along the radial direction of the first track, wherein 0°<α≤35°.
4. The current collecting member according to claim 1, characterized in that: The stamping boss (200) is a shell structure having a cavity inside, the shell structure having an opening (220), the opening (220) being located on a welding end face on the current collecting component body (100), the welding end face being on the current collecting component body (100) and being in a relative position to the mounting end face (110); In the shell structure of the stamping boss (200), the shell wall where the stamping end surface (210) is located has a consistent wall thickness at all locations.
5. The current collecting member according to claim 1, characterized in that: A fluid channel (120) is provided on the current collecting member body (100), the number of the fluid channel (120) is at least one, and the outlet of the fluid channel (120) is provided on the mounting end surface (110).
6. The current collecting member according to claim 5, characterized in that: The cross section of the fluid channel (120) in the radial direction is polygonal.
7. The current collecting member according to claim 1, characterized in that: A first through hole (130) is provided on the current collecting member body (100) along the central axis direction.
8. A battery cell, characterized in that: include: A battery cell body, wherein the battery cell body has tabs (300), and the tabs (300) include a positive tab and a negative tab; The current collecting member according to any one of claims 1 to 7, wherein two current collecting members are provided, one current collecting member is provided on the positive electrode tab, and the other current collecting member is provided on the negative electrode tab.
9. The battery cell according to claim 8, characterized in that The radius of the battery cell body is R, and the length of the current collecting member along the radial direction of the battery cell body is r, wherein r≥0.3R.
10. An electrical device, characterized in that: include: The battery cell according to claim 8 or 9.