Current collector and battery

Abstract

The utility model discloses a current collector and a battery. The current collector comprises a supporting layer, a metal layer, a lithium supplementing layer and a lithium homogenizing layer. In the thickness direction of the current collector, the supporting layer comprises a first surface and a second surface opposite to the first surface; the metal layers are respectively arranged on the first surface and the second surface; the lithium supplementing layer is arranged on the surface, deviating from the supporting layer, of the metal layer; and the lithium homogenizing layer is arranged on the surface, deviating from the metal layer, of the lithium supplementing layer. The lithium battery can solve the problems that in the prior art, the energy density of the battery is low, and the diaphragm is easily punctured due to accumulation of lithium elementary substances.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium ions, and in particular to a current collector and a battery. Background Art

[0002] Composite current collectors are manufactured using advanced processes and feature a sandwich structure consisting of a metal conductive layer, a polymer support layer, and a metal conductive layer. These current collectors can replace traditional rolled aluminum foil or electrolytic copper foil in battery cells and can be used to converge and conduct current in either the positive or negative electrode materials of batteries. They offer advantages such as high safety, high specific energy, long life, low cost, and high compatibility.

[0003] Lithium-ion batteries rely on the reciprocating movement of lithium ions between positive and negative electrodes to store or release energy. The energy density of a lithium-ion battery refers to the amount of energy a battery of a given mass or volume can store or release. During operation, the more lithium ions a battery can store or release per unit mass or volume, the higher its energy density.

[0004] However, during the formation process of lithium-ion batteries, a solid electrolyte interface (SEI) forms on the surface of the negative electrode. While the SEI is crucial to the performance of lithium-ion batteries, its formation consumes a certain amount of active lithium ions, reducing the number of reversible lithium ions in the battery and, consequently, the battery's energy density. Furthermore, during the battery's charge and discharge cycles, lithium dendrites may form on the negative electrode surface. Their growth consumes the electrolyte and leads to the irreversible deposition of metallic lithium. The formation of lithium dendrites can even penetrate the separator, causing a short circuit within the lithium-ion battery, which can lead to thermal runaway and combustion and explosion. Utility Model Content

[0005] The main purpose of the utility model is to provide a current collector and a battery to solve the problems in the prior art of low battery energy density and easy puncture of the diaphragm by accumulation of lithium elements.

[0006] According to one aspect of the present invention, there is provided a current collector comprising:

[0007] a support layer, along a thickness direction of the current collector, the support layer comprising a first surface and a second surface opposite to the first surface;

[0008] Metal layers, the metal layers are respectively disposed on the first surface and the second surface;

[0009] a lithium replenishing layer, the lithium replenishing layer being disposed on a surface of the metal layer facing away from the supporting layer;

[0010] A lithium uniform layer is provided on a surface of the lithium supplementing layer facing away from the metal layer.

[0011] Furthermore, along the thickness direction of the current collector, the thickness of the lithium replenishing layer is 10 nm to 5000 nm; and / or,

[0012] The thickness of the support layer along the thickness direction of the current collector is 2 μm to 8 μm; and / or,

[0013] The thickness of the metal layer along the thickness direction of the current collector is 500 nm to 2000 nm; and / or,

[0014] Along the thickness direction of the current collector, the thickness of the lithium uniform layer is 10 nm to 500 nm.

[0015] Furthermore, the lithium supplement layer includes at least one of a lithium layer, a lithium aluminum alloy layer, a lithium silver alloy layer, a lithium magnesium alloy layer, a lithium calcium alloy layer or a lithium gold alloy layer; and / or,

[0016] The support layer includes at least one of a polybutylene terephthalate layer, a polyamide layer, a polyterephthalate layer, a polyimide layer, a polyethylene layer, a polypropylene layer, a polystyrene layer, a polyvinyl chloride layer, an aramid layer, an acrylonitrile-butadiene-styrene layer, a poly(p-phenylene terephthalamide) layer, a polypropylene layer, a polyoxymethylene layer, an epoxy resin layer, a phenolic resin layer, a polytetrafluoroethylene layer, a polyvinylidene fluoride layer, a silicone rubber layer, a polycarbonate layer, a polyvinyl alcohol layer, or a polyethylene glycol layer; and / or,

[0017] The metal layer includes at least one of a copper layer, an aluminum layer, a copper alloy layer or an aluminum alloy layer; and / or,

[0018] The lithium uniform layer includes at least one of a magnesium layer, a lead layer, a bismuth layer, a gold layer, and a carbon layer.

[0019] Furthermore, the current collector further includes a transition layer, and the transition layer is arranged between the support layer and the metal layer.

[0020] Furthermore, along the thickness direction of the current collector, the thickness of the transition layer is 5 nm to 50 nm.

[0021] Furthermore, the transition layer includes at least one of an aluminum oxide layer, a silicon nitride layer, a nickel alloy layer, an aluminum alloy layer, a copper alloy layer, a titanium alloy layer or a chromium alloy layer.

[0022] Furthermore, the current collector further includes a protective layer, and the protective layer is arranged on a surface of the lithium uniform layer away from the lithium replenishing layer.

[0023] Furthermore, along the thickness direction of the current collector, the thickness of the protective layer is 2 nm to 30 nm.

[0024] Furthermore, the protective layer includes at least one of a nickel layer, an aluminum layer, a copper layer, a titanium layer, a chromium layer, a nickel alloy layer, an aluminum alloy layer, a copper alloy layer, a titanium alloy layer, a chromium alloy layer, an aluminum nitride layer, a silicon nitride layer, an aluminum oxide layer or a silicon oxide layer.

[0025] On the other hand, the present invention further provides a battery, which includes the above-mentioned current collector.

[0026] In the present invention, when the current collector is actually processed, a metal layer can be sputtered or plated on the first and second surfaces of the support layer by a vacuum coating method such as magnetron sputtering or vacuum evaporation, and then a lithium replenishing layer is sputtered or plated on the surface of the metal layer away from the support layer by vacuum physical vapor deposition such as magnetron sputtering or vacuum evaporation, and then a lithium uniform layer is sputtered or plated on the surface of the lithium replenishing layer away from the metal layer by magnetron sputtering or vacuum evaporation. Compared with the structure of the current collector in the prior art, the present invention provides a lithium replenishing layer on the surface of the metal layer away from the support layer. When the current collector is used in a battery, the presence of the lithium replenishing layer can replenish the metal loss during the battery cycle, thereby improving the energy density of the battery and extending the cycle life of the battery to a certain extent. At the same time, by providing a lithium uniform layer on the surface of the lithium replenishing layer away from the metal layer, during the charge and discharge process of the battery, the presence of the lithium uniform layer can guide the formation of lithium element, effectively preventing lithium element accumulation from puncturing the diaphragm, thereby avoiding short circuiting of the positive and negative electrodes of the battery, releasing a large amount of heat, and thus preventing safety accidents caused by thermal runaway of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0028] Figure 1 This is a schematic structural diagram of a current collector disclosed in an embodiment of the present utility model;

[0029] Figure 2 This is a schematic structural diagram of another current collector disclosed in an embodiment of the present utility model.

[0030] The above drawings include the following reference numerals:

[0031] 10. Support layer; 101. First surface; 102. Second surface; 20. Metal layer; 30. Lithium replenishing layer; 40. Transition layer; 50. Protective layer; 60. Lithium uniform layer; 61. Through hole. DETAILED DESCRIPTION

[0032] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0033] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0034] Unless otherwise specifically stated, the relative arrangement of the parts and steps, the numerical expressions and the numerical values ​​set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The techniques, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific values ​​should be interpreted as being merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0035] It should be noted that the thickness direction of the current collector in the present invention is Figure 1 and attached Figure 2 The direction indicated by the letter X.

[0036] See also Figures 1 to 2 As shown, the present invention provides a current collector, including a support layer 10 , a metal layer 20 , a lithium replenishing layer 30 and a lithium uniform layer 60 .

[0037] Among them, along the thickness direction of the current collector, the support layer 10 includes a first surface 101 and a second surface 102 opposite to the first surface 101; the metal layer 20 is respectively arranged on the first surface 101 and the second surface 102; the lithium replenishing layer 30 is arranged on the surface of the metal layer 20 away from the support layer 10; and the lithium uniform layer 60 is arranged on the surface of the lithium replenishing layer 30 away from the metal layer 20.

[0038] In this embodiment, the support layer 10 includes a first surface 101 and a second surface 102. When the current collector is actually processed, the metal layer 20 can be sputtered or plated on the first surface 101 and the second surface 102 of the support layer 10 by a vacuum coating method such as magnetron sputtering or vacuum evaporation. Then, the lithium replenishing layer 30 is sputtered or plated on the surface of the metal layer 20 facing away from the support layer 10 by a vacuum physical vapor deposition method such as magnetron sputtering or vacuum evaporation. Finally, the lithium uniform layer 60 is sputtered or plated on the surface of the lithium replenishing layer 30 facing away from the metal layer 20 by magnetron sputtering or vacuum evaporation. Compared with the structure of the current collector in the prior art, this embodiment provides a lithium replenishing layer 30 on the surface of the metal layer 20 facing away from the support layer 10. When the current collector is used in a battery, the presence of the lithium replenishing layer 30 can replenish the metal loss during the battery cycle, thereby improving the energy density of the battery and extending the cycle life of the battery to a certain extent. At the same time, by providing a lithium uniform layer 60 on the surface of the lithium replenishing layer 30 facing away from the metal layer 20, during the charge and discharge process of the battery, the presence of the lithium uniform layer 60 can guide the formation of lithium elements, effectively preventing lithium elements from puncturing the diaphragm due to accumulation, thereby avoiding short circuits between the positive and negative poles of the battery, releasing a large amount of heat, and thus preventing safety accidents caused by thermal runaway of the battery.

[0039] Further, see Figure 1 As shown, in this embodiment, the lithium uniform layer 60 is provided with a plurality of through holes 61, which are spaced apart and extend through the lithium uniform layer 60 along the thickness direction of the current collector. Since the lithium replenishing layer 30 releases lithium ions, the through holes allow lithium ions to enter and exit, thereby replenishing the lithium lost during the battery cycle, thereby increasing the battery's energy density and extending the battery's cycle life to a certain extent.

[0040] Furthermore, along the thickness direction of the current collector, the thickness of the lithium replenishing layer 30 in this embodiment is 10 nm to 5000 nm, for example, 10 nm, 50 nm, 100 nm, 500 nm, 1000 nm, 2000 nm, 3000 nm, 4000 nm, 5000 nm, etc. When the thickness of the lithium replenishing layer 30 is less than 10 nm, the excessively thin lithium replenishing layer 30 cannot carry a large amount of metal ions. When the current collector is actually used, the lithium replenishing layer 30 is insufficient to continuously replenish the metal loss during the battery cycle, thereby reducing the battery life. When the thickness of the lithium replenishing layer 30 is between 10 nm and 5000 nm, the increase in the thickness of the lithium replenishing layer 30 can effectively compensate for the metal loss during the battery cycle and improve the cycle performance of the electrode. However, the thickness of the lithium replenishing layer 30 should not be too large. When the thickness of the lithium replenishing layer 30 is greater than 5000 nm, the excessively thick lithium replenishing layer 30 hinders the transmission of metal ions, resulting in an increase in the internal resistance of the battery, thereby reducing the cycle performance of the battery. At the same time, it also increases the overall weight of the current collector and increases the production cost of the current collector.

[0041] Optionally, when the current collector is used as a positive electrode, the thickness of the lithium replenishing layer 30 along the thickness direction of the current collector is 10nm to 500nm, for example, 10nm, 50nm, 100nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, etc.; when the current collector is used as a negative electrode, the thickness of the lithium replenishing layer 30 along the thickness direction of the current collector is 500nm to 5000nm, for example, 500nm, 1000nm, 1500nm, 2000nm, 2500nm, 3000nm, 3500nm, 4000nm, 4500nm, 5000nm, etc.

[0042] Furthermore, along the thickness direction of the current collector, the thickness of the support layer 10 in this embodiment is 2 μm to 8 μm, for example, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, etc. Since the metal layer 20 in this embodiment is sputtered or plated on the first surface 101 and the second surface 102 of the support layer 10 by magnetron sputtering or vacuum evaporation, during this process, the support layer 10 must first be fully stretched on a rotatable roller before the metal layer 20 can be sputtered or plated on both surfaces of the support layer 10. At this time, if the thickness of the support layer 10 is less than 2 μm, it is easy to cause the support layer 10 to be damaged during the stretching process, which is not conducive to the subsequent sputtering or plating of the metal layer 20; if the thickness of the support layer 10 is greater than 8 μm, the overall weight of the current collector is increased, and the production cost of the current collector is increased.

[0043] Furthermore, along the thickness direction of the current collector, the thickness of the metal layer 20 in this embodiment is 500 nm to 2000 nm, for example, 500 nm, 600 nm, 800 nm, 1000 nm, 1200 nm, 1400 nm, 1600 nm, 1800 nm, 2000 nm, etc. Figure 1 As shown, in this embodiment, the metal layer 20 is disposed on the support layer 10 to effectively ensure the conductivity of the current collector. However, when the thickness of the metal layer 20 is less than 500 nm, the conductivity of the current collector is likely to be reduced. When the thickness of the metal layer 20 is greater than 2000 nm, the overall weight of the current collector is increased, thereby increasing the production cost of the current collector.

[0044] Furthermore, the lithium replenishing layer 30 in this embodiment includes at least one of a lithium layer, a lithium-aluminum alloy layer, a lithium-silver alloy layer, a lithium-magnesium alloy layer, a lithium-calcium alloy layer, or a lithium-gold alloy layer. Thus, during battery operation, the lithium replenishing layer 30 can be used to replenish lithium consumed during the cycling of the lithium-ion battery.

[0045] Furthermore, along the thickness direction of the current collector, the thickness of the lithium uniform layer 60 in this embodiment is 10 nm to 500 nm, for example, 10 nm, 50 nm, 100 nm, 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, 500 nm, etc. When the thickness of the lithium uniform layer 60 is less than 10 nm, it is not conducive to the formation of lithium element. When the thickness of the lithium uniform layer 60 is greater than 500 nm, the lithium ions released from the lithium replenishment layer 30 are easily deposited on the lithium uniform layer, resulting in a decrease in the lithium ion content and an inability to replenish metal loss during battery cycling. At the same time, an excessively thick lithium uniform layer 60 increases the overall weight of the current collector, thereby increasing the production cost of the current collector.

[0046] Optionally, the support layer 10 in this embodiment includes at least one of a polybutylene terephthalate layer, a polyamide layer, a polyterephthalate layer, a polyimide layer, a polyethylene layer, a polypropylene layer, a polystyrene layer, a polyvinyl chloride layer, an aramid layer, an acrylonitrile-butadiene-styrene layer, a poly(p-phenylene terephthalamide) layer, a polypropylene layer, a polyoxymethylene layer, an epoxy resin layer, a phenolic resin layer, a polytetrafluoroethylene layer, a polyvinylidene fluoride layer, a silicone rubber layer, a polycarbonate layer, a polyvinyl alcohol layer, or a polyethylene glycol layer. In other words, among the above materials, the base material of the support layer 10 can have different combinations. The support layer 10 of this embodiment is made of the above materials, which is conducive to the subsequent coating process. It can be understood that, see Figure 1 As shown, in this embodiment, the support layer 10 is disposed between the two metal layers 20 , which can isolate the two metal layers 20 and effectively prevent current transmission between the two metal layers 20 .

[0047] Specifically, if the coating environment contains particulate dust, particulate matter is likely to form on the surface of the support layer 10. When the coating process is performed on the support layer 10 to form the metal layer 20, the particulate matter will affect the coating uniformity of the metal layer 20, resulting in inconsistent thicknesses of the metal layer 20 coated on the first surface 101 and the second surface 102 of the support layer 10. As a result, the current collector may curl during storage and transportation. Therefore, before the coating process begins, the surface flatness of the support layer 10 must be inspected. In this embodiment, CCD visual inspection equipment is used to inspect particles on the surface of the support layer 10. If particles are present, a UV laser cutting machine is used to remove them.

[0048] Specifically, in this embodiment, since the support layer 10 needs to be rolled up during transportation, if the tension values ​​on the first surface 101 and the second surface 102 of the support layer 10 are similar or even equal, this will cause the first surface 101 and the second surface 102 of the rolled support layer 10 to adhere to each other. Therefore, a corona treatment technology or a plasma treatment technology can be used to treat the first surface 101 or the second surface 102 of the support layer 10, so that the first surface 101 and the second surface 102 have different roughness, which to a certain extent increases the tension difference between the first surface 101 and the second surface 102, thereby preventing the first surface 101 and the second surface 102 of the support layer 10 from adhering to each other, and facilitating the subsequent unrolling of the support layer 10.

[0049] Furthermore, the metal layer 20 in this embodiment includes at least one of a copper layer, an aluminum layer, a copper alloy layer, or an aluminum alloy layer. The metal layer 20 is a functional layer for achieving electron transport. In this embodiment, a combination of the above-mentioned different materials can be selected as the metal layer 20. Since the copper layer, aluminum layer, copper alloy layer, or aluminum alloy layer has good electrical and thermal conductivity, high chemical stability, and good corrosion resistance, this embodiment uses the above-mentioned materials as the base material of the metal layer 20, which can fully utilize the excellent performance of the current collector and enhance the conductivity of the current collector to a certain extent.

[0050] Specifically, when the current collector is used as a positive electrode, the metal layer 20 is preferably an aluminum layer, and the aluminum layer is pure aluminum; when the current collector is used as a negative electrode, the metal layer 20 is preferably a copper layer, and the copper layer is pure copper.

[0051] Furthermore, the lithium uniform layer 60 in this embodiment includes at least one of a magnesium layer, a lead layer, a bismuth layer, a gold layer, and a carbon layer. In other words, the lithium uniform layer may include one of these, or two or more of these (i.e., an alloy of magnesium, lead, bismuth, gold, and carbon). This prevents lithium from accumulating and puncturing the diaphragm, thereby preventing a short circuit between the positive and negative electrodes of the battery, releasing a large amount of heat, and thus preventing safety accidents caused by thermal runaway of the battery.

[0052] Further, see Figure 2 As shown, the current collector of this embodiment further includes a transition layer 40, which is disposed between the support layer 10 and the metal layer 20. The main function of the transition layer 40 is to increase the bonding force between the support layer 10 and the metal layer 20, effectively preventing the metal layer 20 from falling off during the subsequent coating process. At the same time, it can improve the heat resistance of the support layer 10, effectively preventing the support layer 10 from being burned through during the coating process of the metal layer 20.

[0053] Optionally, along the thickness direction of the current collector, the thickness of the transition layer 40 in this embodiment is 5 nm to 50 nm, for example, 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, etc. When the thickness of the transition layer 40 is less than 5 nm, the bonding force between the support layer 10 and the metal layer 20 is reduced, thereby increasing the probability of the metal layer 20 falling off during the subsequent coating process; when the thickness of the transition layer 40 is greater than 50 nm, the overall weight of the current collector is increased, thereby increasing the production cost of the current collector.

[0054] Furthermore, the transition layer 40 in this embodiment includes at least one of an aluminum oxide layer, a silicon nitride layer, a nickel alloy layer, an aluminum alloy layer, a copper alloy layer, a titanium alloy layer, or a chromium alloy layer. In other words, among the aforementioned materials, different combinations of materials can be selected for the transition layer 40 to improve the adhesion between the support layer 10 and the metal layer 20, preventing the metal layer 20 from falling off during the subsequent coating process. This can also improve the heat resistance of the support layer 10, preventing it from burning through during the coating process.

[0055] Further, see Figure 2 As shown, the current collector of this embodiment also includes a protective layer 50, which is disposed on the surface of the lithium uniform layer 60 facing away from the lithium replenishment layer 30. This prevents damage to the lithium replenishment layer 30 during transportation and battery cell preparation, improving the safety of the current collector. Furthermore, due to the electron transition effect and the deposition and dissolution of lithium generated during the battery's charge and discharge processes, the presence of the protective layer 50 facilitates the transfer of electrons and lithium, allowing the current collector to be used as a battery negative electrode.

[0056] Optionally, along the thickness direction of the current collector, the protective layer 50 in this embodiment has a thickness of 2 nm to 30 nm, for example, 2 nm, 4 nm, 5 nm, 8 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, etc. When the thickness of the protective layer 50 is less than 2 nm, mechanical properties may deteriorate, which is not conducive to the processing of the protective layer 50. The lithium replenishing layer 30 may easily react with air during processing, causing safety issues. When the thickness of the protective layer 50 is greater than 30 nm, the overall weight of the current collector is increased, thereby increasing the production cost of the current collector.

[0057] Furthermore, the protective layer 50 in this embodiment includes at least one of a nickel layer, an aluminum layer, a copper layer, a titanium layer, a chromium layer, a nickel alloy layer, an aluminum alloy layer, a copper alloy layer, a titanium alloy layer, a chromium alloy layer, an aluminum nitride layer, a silicon nitride layer, an aluminum oxide layer, or a silicon oxide layer. In other words, among the above materials, different combinations of materials can be selected as the protective layer 50.

[0058] Specifically, in the present invention, it is necessary to first obtain the support layer 10. At this time, the support layer 10 can be prepared or purchased directly, and then the transition layer 40 is sputtered or plated on the first surface 101 and the second surface 102 of the support layer 10 by vacuum coating methods such as magnetron sputtering, vacuum evaporation, or electroplating. Then, the metal layer 20 is sputtered or plated on the surface of the transition layer 40 away from the support layer 10 by vacuum coating methods such as magnetron sputtering, vacuum evaporation, or electroplating. Then, the lithium replenishing layer 30 is sputtered or plated on the surface of the metal layer 20 away from the transition layer 40 by vacuum physical vapor deposition methods such as vacuum evaporation, vacuum sputtering, or ion plating. Then, the lithium uniform layer 60 is sputtered or plated on the surface of the lithium replenishing layer 30 away from the metal layer 20 by magnetron sputtering or vacuum evaporation. Finally, the protective layer 50 is arranged on the surface of the lithium replenishing layer 30 away from the metal layer 20. Among them, if the protective layer 50 includes at least one of a nickel layer, an aluminum layer, a copper layer, a titanium layer, a chromium layer, a nickel alloy layer, an aluminum alloy layer, a copper alloy layer, a titanium alloy layer, and a chromium alloy layer, the protective layer 50 can be processed by vacuum coating methods such as magnetron sputtering, vacuum evaporation, or electroplating; if the protective layer 50 includes at least one of an aluminum nitride layer, a silicon nitride layer, an aluminum oxide layer, or a silicon oxide layer, the protective layer 50 can be processed by vacuum chemical vapor deposition.

[0059] From the above description, it can be seen that the above-mentioned embodiments of the present invention achieve the following technical effects: compared with the structure of the current collector in the prior art, the newly added lithium replenishing layer of the present invention can replenish the lithium consumed by the lithium-ion battery during the cycle; the transition layer can increase the bonding force between the support layer and the metal layer, effectively preventing the metal layer from falling off in the subsequent coating process, and at the same time, can increase the heat resistance of the support layer, preventing the support layer from being burned through in the subsequent coating process; the lithium uniform layer can guide the formation of lithium elements, thereby preventing lithium elements from accumulating and puncturing the diaphragm; the protective layer can protect the lithium replenishing layer, thereby preventing the lithium replenishing layer from being damaged during transportation and preparation of battery cells.

[0060] On the other hand, the present invention also provides a battery comprising the above-mentioned current collector. Therefore, the battery includes all the technical effects of the above-mentioned current collector. Since the technical effects of the current collector have been described in detail above, they will not be repeated here.

[0061] Optionally, the battery in this embodiment can use the above-mentioned current collector as the positive electrode. After coating the positive electrode material and then rolling and cutting, the positive electrode plate and the traditional negative electrode plate (that is, the negative electrode plate without the current collector), the separator and the electrolyte constitute a battery. Since the current collector includes a lithium replenishing layer, the energy density of the battery can be significantly improved, thereby increasing the cycle life and safety of the battery.

[0062] Alternatively, the battery in this embodiment may also use the above-mentioned current collector as the negative electrode, but without applying any negative electrode material, and directly form a battery with a conventional positive electrode sheet (i.e., a positive electrode sheet without the current collector), a separator, and an electrolyte. Of course, a negative electrode material may also be applied to the current collector, and a battery may be formed with a conventional positive electrode sheet (i.e., a positive electrode sheet without the current collector), a separator, and an electrolyte.

[0063] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0064] In addition, it should be noted that the use of words such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above words have no special meaning and therefore cannot be understood as limiting the scope of protection of this utility model.

[0065] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A current collector, characterized in that: include: A support layer (10), along the thickness direction of the current collector, the support layer (10) comprising a first surface (101) and a second surface (102) opposite to the first surface (101); a metal layer (20), the metal layer (20) being disposed on the first surface (101) and the second surface (102), respectively; a lithium replenishing layer (30), the lithium replenishing layer (30) being arranged on a surface of the metal layer (20) facing away from the supporting layer (10); A lithium uniform layer (60) is provided on a surface of the lithium supplement layer (30) facing away from the metal layer (20).

2. The current collector according to claim 1, characterized in that Along the thickness direction of the current collector, the thickness of the lithium replenishing layer (30) is 10 nm to 5000 nm; and / or, Along the thickness direction of the current collector, the thickness of the support layer (10) is 2 μm to 8 μm; and / or, Along the thickness direction of the current collector, the thickness of the metal layer (20) is 500 nm to 2000 nm; and / or, along the thickness direction of the current collector, the thickness of the lithium uniform layer (60) is 10 nm to 500 nm.

3. The current collector according to claim 1 or 2, characterized in that: The lithium supplement layer (30) comprises one of a lithium layer, a lithium aluminum alloy layer, a lithium silver alloy layer, a lithium magnesium alloy layer, a lithium calcium alloy layer or a lithium gold alloy layer; and / or, The support layer (10) comprises one of a polybutylene terephthalate layer, a polyamide layer, a polyterephthalate layer, a polyimide layer, a polyethylene layer, a polypropylene layer, a polystyrene layer, a polyvinyl chloride layer, an aramid layer, an acrylonitrile-butadiene-styrene layer, a poly(p-phenylene terephthalamide) layer, a polypropylene layer, a polyoxymethylene layer, an epoxy resin layer, a phenolic resin layer, a polytetrafluoroethylene layer, a polyvinylidene fluoride layer, a silicone rubber layer, a polycarbonate layer, a polyvinyl alcohol layer or a polyethylene glycol layer; and / or, The metal layer (20) comprises one of a copper layer, an aluminum layer, a copper alloy layer or an aluminum alloy layer; and / or, The lithium uniform layer (60) includes one of a magnesium layer, a lead layer, a bismuth layer, a gold layer and a carbon layer.

4. The current collector according to claim 3, characterized in that The current collector further comprises a transition layer (40), wherein the transition layer (40) is arranged between the support layer (10) and the metal layer (20).

5. The current collector according to claim 4, characterized in that Along the thickness direction of the current collector, the thickness of the transition layer (40) is 5 nm to 50 nm.

6. The current collector according to claim 4, characterized in that The transition layer (40) comprises one of an aluminum oxide layer, a silicon nitride layer, a nickel alloy layer, an aluminum alloy layer, a copper alloy layer, a titanium alloy layer or a chromium alloy layer.

7. The current collector according to claim 1, characterized in that The current collector further comprises a protective layer (50), and the protective layer (50) is arranged on a surface of the lithium uniform layer (60) facing away from the lithium replenishing layer (30).

8. The current collector according to claim 7, characterized in that Along the thickness direction of the current collector, the thickness of the protective layer (50) is 2nm to 30nm.

9. The current collector according to claim 7, characterized in that The protective layer (50) comprises one of a nickel layer, an aluminum layer, a copper layer, a titanium layer, a chromium layer, a nickel alloy layer, an aluminum alloy layer, a copper alloy layer, a titanium alloy layer, a chromium alloy layer, an aluminum nitride layer, a silicon nitride layer, an aluminum oxide layer or a silicon oxide layer.

10. A battery, characterized in that: The battery comprises the current collector according to any one of claims 1 to 9.

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