Composite current collector

Abstract

The utility model discloses a composite current collector, which comprises an insulating layer and a first conducting layer, the first conductive layers are arranged on the two sides of the insulating layer in the first direction; the insulating layer comprises a first insulating region and second insulating regions, and the second insulating regions are arranged on the two opposite sides of the first insulating region in the second direction; the first direction is perpendicular to the second direction; a plurality of holes are formed in the second insulating region; the first conductive layers on the two sides of the insulating layer are electrically connected through conductive substances arranged in the holes. According to the utility model, additional processes can be reduced or eliminated, the manufacturing cost can be reduced, and the yield can be improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a composite current collector. Background Technology

[0002] As lithium-ion battery cells develop towards higher capacity and energy density, the materials used in these cells are also rapidly evolving. The main advantages of composite current collectors include improved battery safety, increased energy density, and reduced cost. In terms of safety, the unique structure of composite current collectors can reduce short-circuit current during internal short circuits, effectively preventing thermal runaway. Furthermore, since polymer materials have a lower density than metals, using composite current collectors can reduce battery weight and increase energy density. In terms of industrialization, composite current collectors have already achieved mass production in consumer electronics batteries, and their application in the power battery field is gradually increasing.

[0003] Currently, the fabrication cost of composite current collectors is high, and because they are inherently non-conductive, pure metal foil needs to be welded to their edges to increase conductivity. This increases process costs and reduces the final yield. Therefore, there is an urgent need to develop a composite current collector to address these issues. Utility Model Content

[0004] The purpose of this invention is to propose a composite current collector that can reduce or eliminate additional processes, lower process costs, and improve yield.

[0005] To solve the above-mentioned technical problems, this utility model provides a composite current collector, including an insulating layer and a first conductive layer;

[0006] The first conductive layer is disposed on both sides of the insulating layer in a first direction;

[0007] The insulating layer includes: a first insulating region and a second insulating region, wherein the second insulating region is disposed on opposite sides of the first insulating region in a second direction; the first direction and the second direction are perpendicular to each other.

[0008] The second insulating region has multiple holes; the first conductive layers on both sides of the insulating layer are electrically connected through conductive materials disposed in the holes.

[0009] Furthermore, the thickness of the insulating layer ranges from 3μm to 4μm.

[0010] Furthermore, the width of the second insulating region ranges from 5μm to 7μm.

[0011] Furthermore, the diameter of the hole ranges from 4mm to 7mm.

[0012] Furthermore, the first conductive layer is connected to the insulating layer by electroplating.

[0013] Furthermore, the conductive material is a conductive material layer disposed on the wall of the hole; the conductive material layer includes a metal plating layer.

[0014] Furthermore, the first conductive layer includes a graphene thin film conductive layer or a carbon nanotube thin film.

[0015] Furthermore, it also includes a second conductive layer; the second conductive layer is disposed on the first conductive layer, and the first conductive layer is located between the insulating layer and the second conductive layer.

[0016] Furthermore, the second conductive layer includes a copper layer.

[0017] Furthermore, the thickness of the second conductive layer ranges from 0.5 μm to 1 μm.

[0018] Through the above technical solution, this utility model has the following beneficial effects:

[0019] By employing an insulating layer and a first conductive layer, with the first conductive layer positioned on both sides of the insulating layer in a first direction, the insulating layer comprises a first insulating region and a second insulating region, the second insulating region being positioned on opposite sides of the first insulating region in a second direction; the first and second directions are perpendicular; the second insulating region has multiple holes; and the first conductive layers on both sides of the insulating layer are electrically connected through conductive materials disposed within the holes. This device, by positioning the first conductive layer on both sides of the insulating layer in the first direction, means that the first conductive layer covers both sides of the insulating layer, thereby forming a conductive path on both sides of the insulating layer; simultaneously, the conductive material within the holes enables electron transport between the first conductive layers on both sides of the insulating layer. Therefore, this device not only reduces or eliminates additional processes but also lowers process costs and improves yield. Attached Figure Description

[0020] Figure 1 This is a side view of the composite current collector in one embodiment of the present invention;

[0021] Figure 2 This is a top view of the insulating layer in a composite current collector according to an embodiment of the present invention.

[0022] In the figure, 11 is the first insulating region; 12 is the second insulating region; 13 is the hole; 2 is the first conductive layer; and 3 is the second conductive layer. Detailed Implementation

[0023] The present invention will now be described with reference to schematic diagrams, which illustrate preferred embodiments of the present invention. It should be understood that those skilled in the art can modify the present invention described herein while still achieving its advantageous effects. Therefore, the following description should be understood as being of general knowledge to those skilled in the art and is not intended to limit the present invention.

[0024] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages). In the description of this utility model, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0025] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0026] The present invention will be described more specifically by way of example in the following paragraphs with reference to the accompanying drawings. The advantages and features of the present invention will become clearer from the following description and claims. It should be noted that the drawings are in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0027] like Figure 1-2 As shown in the figure, this utility model embodiment proposes a composite current collector, including an insulating layer, a first conductive layer 2, and a second conductive layer 3.

[0028] Specifically, the first conductive layer 2 is disposed on both sides of the insulating layer in a first direction; the second conductive layer 3 is disposed on the first conductive layer 2, and the first conductive layer 2 is located between the insulating layer and the second conductive layer 3; the insulating layer includes: a first insulating region 11 and a second insulating region 12, the second insulating region 12 being disposed on opposite sides of the first insulating region 11 in a second direction; the first direction and the second direction are perpendicular; the second insulating region 12 is provided with a plurality of holes 13; the first conductive layers 2 on both sides of the insulating layer are electrically connected through conductive materials disposed in the holes 13.

[0029] The hole 13 extends along the first direction. Figure 1 The y-axis direction is the first direction, and the x-axis direction is the second direction.

[0030] In this embodiment, the first conductive layer 2 is connected to the insulating layer by electroplating. The conductive material is a conductive material layer disposed on the hole wall of the hole 13. The conductive material layer includes a metal plating layer, which means that the conductive material layer (e.g., the metal plating layer) forms a continuous conductive path between the first conductive layers 2 on both sides of the insulating layer, thereby enabling electron transport between the first conductive layers 2 on both sides of the insulating layer. In this embodiment, the first conductive layer 2 is connected to the insulating layer by electroplating, which can effectively achieve electrical connection between different layers. Electroplating is an electroplating through-hole technology that deposits metal (e.g., copper) on the hole wall to form a continuous conductive path.

[0031] In addition, the second conductive layer 3 in this embodiment not only provides electrical connection function, but also enhances the structural stability of the composite current collector, making it more reliable during battery use.

[0032] In this embodiment, the first insulating region 11 and the second insulating region 12 are integrally formed. More specifically, for example, the integrally formed insulating layer is divided into three regions, with the middle region being the first insulating region 11 and the two outer regions being the second insulating regions 12.

[0033] In this embodiment, the first conductive layer 2 is disposed on both sides of the insulating layer in a first direction; the second conductive layer 3 is disposed on the first conductive layer 2, and the first conductive layer 2 is located between the insulating layer and the second conductive layer 3, which can provide additional structural strength and electrical connection function.

[0034] In one embodiment, the first insulating region 11 has an upper surface, a lower surface, a side edge, and a other side edge; the upper surface and the lower surface are disposed opposite to each other, the side edge and the other side edge are disposed opposite to each other, and the upper surface is perpendicular to the side edge; a second insulating region 12 is disposed on both the side edge and the other side edge; the upper surface of the first insulating region 11 and the upper surface of the second insulating region 12 are connected to one of the first conductive layers 2; the lower surface of the first insulating region 11 and the lower surface of the second insulating region 12 are connected to another first conductive layer 2.

[0035] The upper surface of the first insulating region 11 and the upper surface of the second insulating region 12 are located on the same horizontal plane. The lower surface of the first insulating region 11 and the lower surface of the second insulating region 12 are located on the same horizontal plane.

[0036] More specifically, the first conductive layer 2 covers the entire insulating layer, ensuring that both sides of the second insulating region 12 are covered by the first conductive layer 2, thereby improving the overall conductivity of the structure. Furthermore, the complete coverage of the insulating layer with the first conductive layer 2 ensures a uniform current distribution on the battery current collector, reducing localized overheating and current concentration issues, thus improving battery safety and stability. The second conductive layer 3 covers the entire first conductive layer 2, further enhancing the conductivity of the entire structure.

[0037] In a preferred embodiment, the thickness of the insulating layer ranges from 3 μm to 4 μm; the thickness dimension of the insulating layer refers to its dimension in the first direction. For example, the thickness of the insulating layer can be 3 μm, 3.2 μm, 3.4 μm, 3.6 μm, 3.8 μm, and 4 μm. A thickness range of 3 μm to 4 μm provides good mechanical strength while maintaining low weight. This is crucial for battery modules, as they need to minimize weight while ensuring structural stability to improve energy density. Within this thickness range, the material and processing costs of the insulating layer can be effectively controlled, while ensuring that the insulation performance meets the battery's safety requirements. A suitable insulating layer thickness helps reduce the internal resistance of the battery, thereby improving the battery's charge / discharge efficiency and overall performance. Those skilled in the art will understand that the thickness of the insulating layer can be set according to actual needs to achieve the same effect.

[0038] In this embodiment, the insulating layer is made of either PP (polypropylene) or PET (polyethylene terephthalate). Both PP and PET possess high mechanical strength and toughness, enabling them to withstand various mechanical stresses that the battery may encounter during manufacturing and use. PP and PET exhibit good resistance to common chemicals found inside batteries, are less prone to chemical reactions, and thus contribute to extending battery life. The low density of PP and PET helps reduce battery weight and increase energy density. As those skilled in the art will understand, the insulating layer material can be chosen according to actual needs to achieve the same effect.

[0039] In a preferred embodiment, the width of the second insulating region 12 ranges from 5 μm to 7 μm, where the width refers to its dimension in the second direction. For example, the width of the second insulating region 12 can be 5 μm, 5.4 μm, 5.8 μm, 6.2 μm, 6.6 μm, 6.8 μm, and 7 μm. Those skilled in the art will understand that the width of the second insulating region 12 can be set according to actual needs to achieve the same effect. A narrower insulating layer width helps to precisely control the transmission path of electrons through the aperture 13, thereby improving the conductivity of the battery. By precisely controlling the width of the second insulating region 12, the conductive area of ​​the battery assembly can be maximized within a limited space, increasing the energy density of the battery. Setting a specific width range helps to achieve higher precision and consistency during manufacturing, thereby improving product reliability and consistency. Within a width range of 5 μm to 7 μm, the second insulating region 12 can provide sufficient mechanical support without excessively increasing the overall weight of the battery assembly.

[0040] In this embodiment, the second insulating region 12 is bonded to the first conductive layer 2 using an adhesive. Using an adhesive simplifies the manufacturing process of the composite current collector, avoiding complex welding or mechanical connection processes. A suitable adhesive provides strong bond strength, ensuring a firm connection between the second insulating region 12 and the first conductive layer 2, thereby improving the stability of the overall structure. Using an adhesive ensures there are no gaps between the second insulating region 12 and the first conductive layer 2, thus improving electrical insulation performance and preventing current leakage. Adhesive bonding reduces the use of additional materials, helping to lower production costs.

[0041] In a preferred embodiment, the diameter of the hole 13 ranges from 4mm to 7mm. For example, the diameter of the hole 13 can be 4mm, 4.5mm, 5mm, 5.5mm, 6mm, 6.5mm, and 7mm. Those skilled in the art will understand that the diameter of the hole 13 can be set according to actual needs to achieve the same effect. The size of the hole 13 diameter directly affects the electron transport efficiency in the composite current collector. A hole 13 diameter range of 4mm to 7mm helps to provide sufficient electron transport channels, thereby improving the charge and discharge performance of the battery. Within this diameter range, the hole 13 is not so large as to weaken the structural strength of the insulating layer, nor so small as to limit the electron transport efficiency, thus achieving a balance between maintaining structural integrity and electron transport efficiency. An appropriate hole 13 size helps to control the current during an internal short circuit in the battery, reducing the risk of thermal runaway and thus improving battery safety.

[0042] In this embodiment, the plurality of holes 13 are uniformly distributed. The uniform distribution of holes 13 helps to achieve a uniform distribution of current on the battery current collector, reducing problems such as localized overheating and current concentration, thereby improving the safety and stability of the battery. A uniform electron transport path can reduce the resistance to electron transport, improve the battery's charge and discharge efficiency, and extend the battery's lifespan. The uniform distribution of holes 13 helps to maintain the overall structural stability of the insulating layer, avoiding localized stress concentration caused by uneven distribution of holes 13. The uniform distribution of holes 13 helps the battery maintain stable performance during multiple charge and discharge cycles, reducing performance degradation.

[0043] In one specific example, the first conductive layer 2 comprises a graphene film conductive layer or a carbon nanotube film. Choosing a graphene film or a carbon nanotube film as the first conductive layer 2 can improve battery performance while enhancing battery safety, stability, and environmental adaptability. Those skilled in the art will understand that, to achieve the same effect, the first conductive layer 2 can also be selected from other embodiments besides the graphene film conductive layer or carbon nanotube film used in this embodiment.

[0044] In this embodiment, the second conductive layer 3 includes a copper layer. Using a copper layer as the second conductive layer 3 can not only improve the performance and safety of the battery, but also reduce costs and improve the battery's durability and environmental adaptability.

[0045] In a preferred embodiment, the thickness of the second conductive layer 3 ranges from 0.5 μm to 1 μm; the thickness of the second conductive layer 3 refers to its dimension in the first direction. For example, the width of the second insulating region 12 can be 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, and 1 μm. Those skilled in the art will understand that the thickness of the second conductive layer 3 can be set according to actual needs to achieve the same effect. Within this thickness range, the second conductive layer 3 can provide sufficient conductivity while maintaining low resistance, thereby improving the charging and discharging efficiency of the battery. Controlling the thickness of the second conductive layer 3 within the range of 0.5 μm to 1 μm allows for optimization of cost, weight, flexibility, and safety while ensuring battery performance, providing more flexibility and optimization space for battery design.

[0046] In this embodiment, the 4μm thick insulating layer can be cut into strips of fixed specifications, with 6cm wide tabs on each side. Figure 2 The region containing the second insulating region 12 can be considered as the ear region. Holes 13 with a diameter of 6 mm are uniformly fabricated in the ear region using laser technology to facilitate electron transport. Then, the second insulating region 12 with the fabricated holes 13 is composited with a 1 μm graphene conductive film layer using an adhesive. The graphene conductive film layer is located on both sides of the second insulating region 12, and also on both sides of the first insulating region 11, to enhance conductivity and reduce the impact of the insulating layer. Alternatively, a 99.7% pure copper target can be used as the sputtering source, and copper atoms are uniformly deposited onto the graphene conductive film layer on both sides away from the second insulating region 12 using magnetron sputtering to form a copper layer. The thickness of the copper layer on both sides is controlled to 1 μm, thereby obtaining the prepared composite current collector with a total thickness of 8 μm. Therefore, in this embodiment, multiple holes 13 are formed by uniformly drilling holes in the second insulating region 12 to facilitate electron transport, while a graphene conductive film layer is added to each side of the second insulating region 12 to increase conductivity.

[0047] In summary, the composite current collector proposed in this utility model has the following advantages:

[0048] By employing an insulating layer and a first conductive layer, with the first conductive layer positioned on both sides of the insulating layer in a first direction, the insulating layer comprises a first insulating region and a second insulating region, the second insulating region being positioned on opposite sides of the first insulating region in a second direction; the first and second directions are perpendicular; the second insulating region has multiple holes; and the first conductive layers on both sides of the insulating layer are electrically connected through conductive materials disposed within the holes. This device, by positioning the first conductive layer on both sides of the insulating layer in the first direction, means that the first conductive layer covers both sides of the insulating layer, thereby forming a conductive path on both sides of the insulating layer; simultaneously, the conductive material within the holes enables electron transport between the first conductive layers on both sides of the insulating layer. Therefore, this device not only reduces or eliminates additional processes but also lowers process costs and improves yield.

[0049] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A composite current collector, characterized in that, Includes an insulating layer and a first conductive layer; The first conductive layer is disposed on both sides of the insulating layer in a first direction; The insulating layer includes: a first insulating region and a second insulating region, wherein the second insulating region is disposed on opposite sides of the first insulating region in a second direction; the first direction and the second direction are perpendicular to each other. The second insulating region has multiple holes; the first conductive layers on both sides of the insulating layer are electrically connected through conductive materials disposed in the holes.

2. The composite current collector as described in claim 1, characterized in that, The thickness of the insulating layer ranges from 3μm to 4μm.

3. The composite current collector as described in claim 1, characterized in that, The width of the second insulating region ranges from 5μm to 7μm.

4. The composite current collector as described in claim 1, characterized in that, The diameter of the hole ranges from 4mm to 7mm.

5. The composite current collector as described in claim 1, characterized in that, The first conductive layer is connected to the insulating layer by electroplating.

6. The composite current collector as described in claim 1, characterized in that, The conductive material is a conductive material layer disposed on the wall of the hole; the conductive material layer includes a metal plating layer.

7. The composite current collector as described in claim 1, characterized in that, The first conductive layer includes a graphene thin film conductive layer or a carbon nanotube thin film.

8. The composite current collector as described in claim 1, characterized in that, It also includes a second conductive layer; the second conductive layer is disposed on the first conductive layer, and the first conductive layer is located between the insulating layer and the second conductive layer.

9. The composite current collector as described in claim 8, characterized in that, The second conductive layer includes a copper layer.

10. The composite current collector as described in claim 8, characterized in that, The thickness of the second conductive layer ranges from 0.5 μm to 1 μm.

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