Three-dimensional composite copper foil for solid-state lithium batteries

Abstract

Three-dimensional composite copper foil for solid-state lithium batteries, characterized in that it comprises a carrier layer, wherein the carrier layer is formed as a porous film layer or fiber film layer, and a first metallization layer and a second metallization layer are arranged on both sides of the carrier layer, wherein a third metallization layer is arranged on the side of the first metallization layer facing away from the carrier layer, a fourth metallization layer is arranged on the side of the second metallization layer facing away from the carrier layer, a first conductive copper layer is arranged on the side of the third metallization layer facing away from the first metallization layer, and a second conductive copper layer is arranged on the side of the fourth metallization layer facing away from the second metallization layer.

Description

Technical FieldThe present invention relates to the technical field of battery manufacture and, more particularly, to a three-dimensional composite copper foil for solid state lithium batteries.Prior ArtIn conventional solid state lithium batteries, copper foil is usually used as a negative current collector. Since the copper foil is normally made of solid copper, it is relatively heavy and consumes much copper material, resulting in high cost. This increases the weight of the solid state lithium batteries and their manufacturing costs. At the same time, the lithium ions in the electrolyte move relatively slowly from one side of the copper foil to the other during the charging and discharging operation of the solid lithium battery because there are no holes in the copper foil for the passage of the lithium ions in the electrolyte, which reduces the charging and discharging rate of the solid lithium batteries.Content of the Present Utility ModelIn order to overcome the deficiencies in the prior art, the present invention provides a three-dimensional composite copper foil for solid state lithium batteries, which can reduce the weight of the solid state lithium batteries and reduce the manufacturing cost while increasing the charging and discharging rate of the solid state lithium batteries.The above technical problems are solved by the following solutions of the present invention:In a first aspect of the present invention, a three-dimensional composite copper foil for solid-state lithium batteries is provided, which comprises a carrier layer, wherein the carrier layer is formed as a porous foil layer or fiber foil layer, and a first metallization layer and a second metallization layer are respectively arranged on both sides of the carrier layer, wherein a third metallization layer is arranged on the side of the first metallization layer facing away from the carrier layer, a fourth metallization layer is arranged on the side of the second metallization layer facing away from the carrier layer, a first conductive copper layer is arranged on the side of the third metallization layer facing away from the first metallization layer, and a second conductive copper layer is arranged on the side of the fourth metallization layer facing away from the second metallization layer.In a preferred embodiment, the porous film layer is a porous PET film layer, PP film layer, PI film layer or PE film layer.In a preferred embodiment, the fiber film layer is a PET fiber film layer, PP fiber film layer, PI fiber film layer or PE fiber film layer.In a preferred embodiment, the porous film layer or fiber film layer is provided with pores which have a pore diameter in the range from 0.05 to 500 μm and a porosity in the range from 0.1% to 80%.In a preferred embodiment, the first and second metallization layers each consist of one or more combinations of cobalt, aluminum, nickel, cadmium, magnesium, lithium and manganese.In a preferred embodiment, the third and fourth metallization layers each consist of copper or copper alloy.In a preferred embodiment, the carrier layer has a thickness of 1 to 30 μm.In a preferred configuration, the first and second metallization layers each have a thickness of 5 to 100 nm, and the third and fourth metallization layers each have a thickness of 10 to 200 nm.In a preferred embodiment, the first and second conductive copper layers each have a thickness of 500 to 2000 nm.In a second aspect of the present invention, there is provided a method of manufacturing a three-dimensional composite copper foil for solid state lithium batteries, comprising the steps of:S1. providing a carrier layer, wherein the carrier layer is configured as a porous film layer or fiber film layer;S2. applying a first and a second metallization layer on both sides of the carrier layer by magnetron sputtering, vapor deposition or chemical deposition;S3. applying a third metallization layer on the side of the first metallization layer facing away from the carrier layer and a fourth metallization layer on the side of the second metallization layer facing away from the carrier layer by magnetron sputtering, vapor deposition or chemical deposition;S4. applying a first conductive copper layer to the side of the third metallization layer facing away from the first metallization layer and a second conductive copper layer to the side of the fourth metallization layer facing away from the second metallization layer by electroplating or vapor deposition.The present invention has advantages that the disposed support layer formed as a porous foil layer or a fiber foil layer can reduce the weight of the composite copper foil and reduce the consumption of copper material, thereby reducing the weight of the solid state lithium batteries and the manufacturing cost thereof. During the charging and discharging process of the solid lithium batteries, the pores in the porous foil layer or the fiber foil layer may serve as channels for the movement of lithium ions in the electrolyte, so that the lithium ions in the electrolyte of the solid lithium batteries can rapidly move from one side of the composite copper foil to the other side, which increases the charging and discharging rate of the solid lithium batteries. The first and second conductive copper layers can meet the current carrying capacity and tensile strength requirements of the composite copper foil, thereby meeting the performance requirements of solid state lithium batteries. Moreover, the disposed first metallization layer serves as insulation between the first conductive copper layer and the support layer, while the disposed second metallization layer serves as insulation between the second conductive copper layer and the support layer, thereby protecting the support layer. During the high and low temperature cycle tests of the solid state lithium batteries, burning through of the support layer is prevented, thereby enhancing the stability of the composite copper foil during these tests. The adhesion between the first metallization layer and the first conductive copper layer and between the second metallization layer and the second conductive copper layer is increased by the arranged third and fourth metallization layers, whereby detachment of the first and second conductive copper layers is prevented.Brief Description of the DrawingsThe present invention will be explained in more detail below with reference to the attached drawings and embodiments. FIG. 1 is a schematic diagram of a three-dimensional composite copper foil for solid state lithium batteries according to an embodiment of the present invention; FIG. 2 is a flow chart showing a manufacturing method of a three-dimensional composite copper foil for solid lithium batteries based on the three-dimensional composite copper foil for solid lithium batteries shown in FIG. 1.DETAILED EMBODIMENTSHereinafter, the concept, specific construction and technical effects of the present invention will be clearly and fully described in conjunction with embodiments and drawings in order to fully understand the object, features and effects of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments that will become apparent to a person skilled in the art without inventive activity fall within the scope of this invention. Moreover, all coupling / connection relationships mentioned in this utility model not only relate to direct connections of components, but it is also possible to add or remove connecting means depending on the specific implementation in order to create an optimized connection. The various technical features of the present invention can be combined with each other provided that they do not conflict with each other.As shown in FIG. 1, a three-dimensional composite copper foil for solid state lithium batteries provided in an embodiment of the present invention includes a support layer 10, wherein the support layer 10 is formed as a porous foil layer or a fiber foil layer. On both sides of the carrier layer 10, a first metallization layer 20 and a second metallization layer 30 are arranged in each case. On the side of the first metallization layer 20 facing away from the carrier layer 10, a third metallization layer 40 is arranged. On the side of the second metallization layer 30 facing away from the carrier layer 10, a fourth metallization layer 50 is arranged. On the side of the third metallization layer 40 facing away from the first metallization layer 20, a first conductive copper layer 60 is arranged. On the side of the fourth metallization layer 50 facing away from the second metallization layer 30, a second conductive copper layer 70 is arranged.By the above-described construction, the composite copper foil of the present invention has a support layer 10 formed as a porous foil layer or a fiber foil layer. It serves to support the entire composite copper foil and is characterized by low weight, low costs and good extensibility. It can reduce the weight of the composite copper foil as well as reduce the consumption of copper material, thereby reducing the weight of the solid state lithium batteries and the manufacturing cost thereof. At the same time, it improves the extensibility of the composite copper foil and avoids damage or breakages which might be caused by the expansion or contraction of the electrolyte during the charging and discharging process of the solid state lithium batteries. During the charging and discharging process of the solid lithium batteries, the pores in the porous foil layer or the fiber foil layer may serve as channels for the movement of lithium ions in the electrolyte, so that the lithium ions in the electrolyte of the solid lithium batteries can rapidly move from one side of the composite copper foil to the other side, which increases the charging and discharging rate of the solid lithium batteries. The disposed first conductive copper layer 60 and second conductive copper layer 70 have good electrical conductivity and can meet the current carrying capacity as well as the tensile strength requirements of the composite copper foil, thereby meeting the performance requirements of solid state lithium batteries. The disposed first metallization layer 20 serves as insulation between the first conductive copper layer 60 and the support layer 10, while the disposed second metallization layer 30 serves as insulation between the second conductive copper layer 70 and the support layer 10, thereby protecting the support layer 10. During the high and low temperature cycle tests of the solid state lithium batteries, burning through of the support layer 10 is prevented, which increases the stability of the composite copper foil during these tests. The disposed third metallization layer 40 improves adhesion between the first metallization layer 20 and the first conductive copper layer 60, thereby preventing detachment of the first conductive copper layer 60. Also, the fourth metallization layer 50 disposed improves adhesion between the second metallization layer 30 and the second conductive copper layer 70, thereby preventing detachment of the second conductive copper layer 70.In this embodiment, the first metallization layer 20 and the second metallization layer 30 are respectively applied to both sides of the carrier layer 10 by magnetron sputtering, vapor deposition or chemical deposition. On the side of the first metallization layer 20 facing away from the carrier layer 10, the third metallization layer 40 is applied by magnetron sputtering, vapor deposition or chemical deposition. On the side of the second metallization layer 30 facing away from the carrier layer 10, the fourth metallization layer 50 is applied by magnetron sputtering, vapor deposition or chemical deposition. On the side of the third metallization layer 40 facing away from the first metallization layer 20, the first conductive copper layer 60 is applied by electroplating or vapor deposition. On the side of the fourth metallization layer 50 facing away from the second metallization layer 30, the second conductive copper layer 70 is applied by electroplating or vapor deposition.The porous film layer is a PET porous film layer (polyethylene terephthalate), PP film layer (polypropylene), PI film layer (polyimide) or PE film layer (polyethylene). The porous PET, PP, PI and PE foil layers have a low density, whereby the weight of the composite copper foil can be further reduced. This allows an additional weight reduction of the solid lithium batteries with simultaneously simplified production.The fiber sheet layer is a PET fiber sheet layer, PP fiber sheet layer, PI fiber sheet layer or PE fiber sheet layer. The PET, PP, PI and PE fiber film layers have a low density, whereby the weight of the composite copper film can be further reduced. This allows an additional weight reduction of the solid lithium batteries with simultaneously simplified production.The porous film layer or fiber film layer is provided with pores having a pore diameter in the range of 0.05 to 500 μm and a porosity in the range of 0.1% to 80%. These values ensure that lithium ions can pass through the pores and at the same time metal is prevented from depositing in the pores during the application of the first metallization layer 20 and the second metallization layer 30 on both sides of the carrier layer 10 by methods such as magnetron sputtering, vapor deposition or chemical deposition.The first and second metallization layers 20 and 30 are each comprised of one or more combinations of cobalt, aluminum, nickel, cadmium, magnesium, lithium, and manganese. By means of the combination of a plurality of metals, a dense insulation layer can be formed.The third and fourth metallization layers 40 and 50 are each made of copper or copper alloy, and the first and second conductive copper layers 60 and 70 are each made of copper. By using copper or copper alloy for the third and fourth metallization layers 40 and 50, the formation rate of the first conductive copper layer 60 and the second conductive copper layer 70 can be increased if the first conductive copper layer 60 is applied by electroplating or vapor deposition on the side of the third metallization layer 40 facing away from the first metallization layer 20 and the second conductive copper layer 70 is applied by electroplating or vapor deposition on the side of the fourth metallization layer 50 facing away from the second metallization layer 30.The backing layer 10 has a thickness of 1 to 30 μm (microns), preferably 10 μm. The first metallization layer 20 and the second metallization layer 30 each have a thickness of 5 to 100 nm (nanometers), preferably 50 nm. The third metallization layer 40 and the fourth metallization layer 50 each have a thickness of 10 to 200 nm, preferably 100 nm. The first conductive copper layer 60 and the second conductive copper layer 70 each have a thickness of 500 to 2000 nm, preferably 1000 nm. With these thicknesses, the total thickness of the composite copper foil of the present invention is in the range of 2.03 to 34.6 μm. The small thickness enables a further reduction in the weight of the composite copper foil and thus also in the weight of the solid lithium batteries.As shown in FIG. 2, based on the above-mentioned composite copper foil for solid lithium batteries, a method for producing a composite copper foil for solid lithium batteries is also provided, which comprises the following steps:S1. Providing a support layer 10. The support layer 10 has a thickness of 1 to 30 μm. The carrier layer 10 is formed as a porous film layer or fiber film layer. The porous film layer is a PET porous film layer, PP porous film layer, PI porous film layer or PE porous film layer. The fiber sheet layer is a PET fiber sheet layer, PP fiber sheet layer, PI fiber sheet layer or PE fiber sheet layer. The porous film layer or fiber film layer is provided with pores having a pore diameter in the range of 0.05 to 500 μm and a porosity in the range of 0.1% to 80%.S2. applying a first metallization layer 20 and a second metallization layer 30 to both sides of the carrier layer 10 by magnetron sputtering, vapor deposition or chemical deposition. The first metallization layer 20 and the second metallization layer 30 are each comprised of one or more combinations of cobalt, aluminum, nickel, cadmium, magnesium, lithium, and manganese. The first metallization layer 20 and the second metallization layer 30 each have a thickness of 5 to 100 nm.S3. applying a third metallization layer 40 on the side of the first metallization layer 20 facing away from the carrier layer 10 and a fourth metallization layer 50 on the side of the second metallization layer 30 facing away from the carrier layer 10 by magnetron sputtering, vapor deposition or chemical deposition. The third metallization layer 40 and the fourth metallization layer 50 are each made of copper or copper alloy. The third metallization layer 40 and the fourth metallization layer 50 each have a thickness of 10 to 200 nm.S4. applying a first conductive copper layer 60 on the side of the third metallization layer 40 facing away from the first metallization layer 20 and a second conductive copper layer 70 on the side of the fourth metallization layer 50 facing away from the second metallization layer 30 by electroplating or vapor deposition. The first conductive copper layer 60 and the second conductive copper layer 70 are each made of copper, and the first conductive copper layer 60 and the second conductive copper layer 70 each have a thickness in the range of 500 to 2000 nm.The manufacturing method of the present invention has a simple process and is easily performed. The produced composite copper foil is light and cost-effective. This can reduce the weight of the solid state lithium batteries and reduce the manufacturing cost. At the same time, the charging and discharging rate of the solid lithium batteries can be increased, which greatly satisfies the usage requirements.The foregoing presents a detailed description of the preferred embodiments of the present invention, but this invention is not limited to the described embodiments. One skilled in the art can make equivalent modifications or substitutions without abandoning the spirit of this utility model, and these equivalent modifications or substitutions all fall within the scope of protection defined by the claims of the application.

Claims

Three-dimensional composite copper foil for solid lithium batteries, characterized in that it comprises a carrier layer, wherein the carrier layer is formed as a porous foil layer or fiber foil layer, and a first metallization layer and a second metallization layer are respectively arranged on both sides of the carrier layer, wherein a third metallization layer is arranged on the side of the first metallization layer facing away from the carrier layer, a fourth metallization layer is arranged on the side of the second metallization layer facing away from the carrier layer, a first conductive copper layer is arranged on the side of the third metallization layer facing away from the first metallization layer, and a second conductive copper layer is arranged on the side of the fourth metallization layer facing away from the second metallization layer.The three-dimensional composite copper foil for solid lithium batteries according to claim 1, characterized in that the porous foil layer is a PET porous foil layer, PP porous foil layer, PL porous foil layer or PE porous foil layer.The three-dimensional composite copper foil for solid lithium batteries according to claim 1, characterized in that the fiber foil layer is a PET fiber foil layer, PP fiber foil layer, PI fiber foil layer or PE fiber foil layer.The three-dimensional composite copper foil for solid lithium batteries according to claim 1, characterized in that the porous foil layer or fiber foil layer is provided with pores having a pore diameter in the range of 0.05 to 500 μm and a porosity in the range of 0.1% to 80%.The three-dimensional composite copper foil for solid lithium batteries according to claim 1, characterized in that the first and second metallization layers each consist of one or more combinations of cobalt, aluminum, nickel, cadmium, magnesium, lithium and manganese.Three-dimensional composite copper foil for solid lithium batteries according to claim 1, characterised in that the third and fourth metallisation layers each consist of copper or copper alloy.Three-dimensional composite copper foil for solid lithium batteries according to claim 1, characterized in that the support layer has a thickness of 1 to 30 μm.The three-dimensional composite copper foil for solid lithium batteries according to claim 1, characterized in that the first and second metallization layers each have a thickness of 5 to 100 nm, and the third and fourth metallization layers each have a thickness of 10 to 200 nm.The three-dimensional composite copper foil for solid lithium batteries according to claim 1, characterized in that the first and second conductive copper layers each have a thickness of 500 to 2000 nm.Three-dimensional composite copper foil for solid lithium batteries, characterized in that it has: • a porous carrier layer or fiber foil layer; • on both sides of the carrier layer in each case a first and second metallization layer, produced by magnetron sputtering, vapor deposition or chemical deposition; • on the sides of the first and second metallization layer facing away from the carrier layer in each case a third and fourth metallization layer, likewise applied by magnetron sputtering, vapor deposition or chemical deposition; • on the sides of the third and fourth metallization layer facing away from the carrier layer in each case a first and second conductive copper layer, applied by electroplating or vapor deposition."**"

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