Three-Dimensional Composite Copper Foil for Solid Lithium Batteries
The three-dimensional composite copper foil addresses weight and cost issues in solid lithium batteries by using a porous or fiber membrane support layer and conductive copper layers, enhancing lithium ion migration and discharge speed.
Patent Information
- Application Number
- JP2025001697U
- Authority / Receiving Office
- JP · JP
- Patent Type
- Utility models
- Current Assignee / Owner
- Priority Date
- 2024-10-24
- Filing Date
- 2025-05-27
- Publication Date
- 2025-07-25
- Estimated Expiration
- 2035-05-27
AI Technical Summary
Conventional solid lithium batteries use heavy solid copper foils as negative electrodes, leading to increased weight, high manufacturing costs, and slow lithium ion migration during charge and discharge processes.
A three-dimensional composite copper foil is developed with a porous or fiber membrane support layer and multiple metallization and conductive copper layers, enhancing lithium ion migration and reducing weight and manufacturing costs.
The composite copper foil reduces weight and manufacturing costs while improving charge and discharge speed and stability during temperature cycles, ensuring effective lithium ion migration and adhesion of conductive layers.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of battery manufacturing, and specifically to a three-dimensional composite copper foil for solid lithium batteries.
Background Art
[0002] In conventional solid lithium batteries, copper foil is generally used as the negative electrode current collector. Since the copper foil is generally solid copper, it is heavy, the amount of copper material used is large, and the cost is high. Therefore, the weight of the solid lithium battery increases, and the manufacturing cost of the solid lithium battery rises. At the same time, during the charge and discharge process of the solid lithium battery, since there are no pores in the copper foil through which lithium ions in the electrolyte can pass, the speed at which lithium ions in the electrolyte move from one side of the copper foil to the opposite side of the copper foil becomes slow, and the charge and discharge speed of the solid lithium battery decreases.
Summary of the Invention
Problems to be Solved by the Invention
[0003] In order to overcome the drawbacks of the prior art, the present invention provides a three-dimensional composite copper foil for solid lithium batteries that can reduce the weight of the solid lithium battery, reduce the manufacturing cost of the solid lithium battery, and improve the charge and discharge speed of the solid lithium battery.
[0004] The technical solutions adopted by the present invention to solve its technical problems are as follows.
[0005] In a first aspect of the present invention, a three-dimensional composite copper foil for solid lithium batteries is provided. The three-dimensional composite copper foil for solid lithium batteries includes a support layer, the support layer is a porous membrane layer or a fiber membrane layer, a first metallization layer and a second metallization layer are respectively provided on both sides of the support layer, a third metallization layer is provided on the surface of the first metallization layer away from the support layer, a fourth metallization layer is provided on the surface of the second metallization layer away from the support layer, a first conductive copper layer is provided on the surface of the third metallization layer away from the first metallization layer, and a second conductive copper layer is provided on the surface of the fourth metallization layer away from the second metallization layer.
[0006] As a preferable technical solution, the porous membrane layer is a PET porous membrane layer, a PP porous membrane layer, a PI porous membrane layer or a PE porous membrane layer.
[0007] As a preferable technical solution, the fiber membrane layer is a PET fiber membrane layer, a PP fiber membrane layer, a PI fiber membrane layer or a PE fiber membrane layer.
[0008] As a preferable technical solution, the pores of the porous membrane layer or the fiber membrane layer have a pore diameter of 0.05 to 500 μm and a porosity of 0.1% to 80%.
[0009] As a preferable technical solution, the materials of the first metallization layer and the second metallization layer are both one or a combination of more than one of cobalt, aluminum, nickel, cadmium, magnesium, lithium and manganese.
[0010] As a preferable technical solution, the materials of the third metallization layer and the fourth metallization layer are both copper or a copper alloy.
[0011] As a preferable technical solution, the thickness of the support layer is 1 to 13 μm.
[0012] As a preferable technical solution, the first metallization layer and the second metallization layer both have a thickness of 5 to 100 nm, and the third metallization layer and the fourth metallization layer both have a thickness of 10 to 200 nm.
[0013] As a preferable technical solution, the first conductive copper layer and the second conductive copper layer both have a thickness of 500 to 2000 nm.
[0014] The beneficial effects of the present invention are as follows. The present invention can reduce the weight of the composite copper foil and the amount of copper material used by means of the provided support layer which is a porous membrane layer or a fiber membrane layer, and can reduce the weight and manufacturing cost of the solid lithium battery. Further, during the charge and discharge process of the solid lithium battery, the pores on the porous membrane layer or the fiber membrane layer serve as the migration path of lithium ions in the electrolyte, so that the lithium ions in the electrolyte of the solid lithium battery can quickly migrate from one side of the composite copper foil to the opposite side, thereby improving the charge and discharge rate of the solid lithium battery. Also, the provided first conductive copper layer and second conductive copper layer can meet the requirements of the current-carrying performance and tensile strength of the composite copper foil, and can meet the performance requirements of the solid lithium battery. Furthermore, the provided first metallization layer serves to separate the first conductive copper layer from the support layer, and the provided second metallization layer serves to separate the second conductive copper layer from the support layer, thereby protecting the support layer. It is possible to prevent the support layer from burning out during the high-temperature and low-temperature cycle test of the solid lithium battery, and improve the stability of the composite copper foil during the high-temperature and low-temperature cycle test of the solid lithium battery. The provided third metallization layer and fourth metallization layer can improve the adhesion between the first metallization layer and the first conductive copper layer, and the adhesion between the second metallization layer and the second conductive copper layer, thereby preventing the first conductive copper layer and the second conductive copper layer from falling off.
Brief Description of the Drawings
[0015] Hereinafter, the present invention will be further described in conjunction with the accompanying drawings and examples.
[0016]
Figure 1
Figure 2
Embodiments for Carrying Out the Invention
[0017] To fully understand the purpose, features, and effects of the present invention, the concept, specific configuration, and technical effects of the present invention will be clearly and completely described below in conjunction with the embodiments and the drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts are included within the protection scope of the present invention. In addition, all connection / connection relationships related to this patent do not simply refer to the direct connection of components, but rather refer to the fact that a more excellent connection structure can be formed by adding or reducing connection accessories according to the specific implementation situation. The various technical features of the present invention can be combined with each other without contradiction.
[0018] Referring to FIG. 1, the three-dimensional composite copper foil for a solid lithium battery provided by an embodiment of the present invention includes a support layer 10 which is a porous film layer or a fiber film layer. On both sides of the support layer 10, a first metallization layer 20 and a second metallization layer 30 are respectively provided. On the surface of the first metallization layer 20 away from the support layer 10, a third metallization layer is provided. On the surface of the second metallization layer 30 away from the support layer 10, a fourth metallization layer 50 is provided. On the surface of the third metallization layer 40 away from the first metallization layer 20, a first conductive copper layer 60 is provided. On the surface of the fourth metallization layer 50 away from the second metallization layer 30, a second conductive copper layer 70 is provided.
[0019] With the above structure, in the composite copper foil of the present invention, the support layer 10 is a porous membrane layer or a fiber membrane layer, which plays a role in supporting the entire composite copper foil, and has characteristics such as light weight, low cost, and good ductility. It can reduce the weight of the composite copper foil and the amount of copper material used, so that the weight and manufacturing cost of the solid lithium battery can be reduced. At the same time, the ductility of the composite copper foil can be improved, and in the charging and discharging process of the solid lithium battery, damage or breakage caused by the expansion or contraction of the electrolyte can be avoided. Also, in the charging and discharging process of the solid lithium battery, the pores in the porous membrane layer or the fiber membrane layer serve as the migration path of lithium ions in the electrolyte, so that the lithium ions in the electrolyte of the solid lithium battery can quickly migrate from one side of the composite copper foil to the opposite side of the composite copper foil, and the charging and discharging speed of the solid lithium battery can be improved. The provided first conductive copper layer 60 and second conductive copper layer 70 have good conductivity and can meet the requirements of the current-carrying performance and tensile strength of the composite copper foil, and can meet the performance requirements of the solid lithium battery. The provided first metallization layer 20 serves to separate the first conductive copper layer 60 from the support layer 10, and the provided second metallization layer 30 serves to separate the second conductive copper layer 70 from the support layer 10, thereby protecting the support layer 10. During the high-temperature and low-temperature cycle test of the solid lithium battery, burnout of the support layer 10 can be prevented, and the stability of the composite copper foil during the high-temperature and low-temperature cycle test of the solid lithium battery is improved. The provided third metallization layer 40 can improve the adhesion between the first metallization layer 20 and the first conductive copper layer 60, and can prevent the first conductive copper layer from falling off. The provided fourth metallization layer 50 can improve the adhesion between the second metallization layer 30 and the second conductive copper layer 70, and can prevent the second conductive copper layer 70 from falling off.
[0020] In this embodiment, on both sides of the support layer 10, a first metallization layer 20 and a second metallization layer 30 are respectively provided by means of magnetron sputtering, vapor deposition, or chemical plating. On the surface of the first metallization layer 20 away from the support layer 10, a third metallization layer 40 is provided by means of magnetron sputtering, vapor deposition, or chemical plating. On the surface of the second metallization layer 30 away from the support layer 10, a fourth metallization layer 50 is provided by means of magnetron sputtering, vapor deposition, or chemical plating. On the surface of the third metallization layer 40 away from the first metallization layer 20, a first conductive copper layer 60 is provided by means of electroplating or vapor deposition. On the surface of the fourth metallization layer 50 away from the second metallization layer 30, a second conductive copper layer 70 is provided by means of electroplating or vapor deposition.
[0021] The porous membrane layer is a PET (Polyethylene terephthalate) porous membrane layer, a PP (Polypropylene) porous membrane layer, a PI (Polyimide) porous membrane layer, or a PE (Polyethylene) porous membrane layer. Since the PET porous membrane layer, the PP porous membrane layer, the PI porous membrane layer, and the PE porous membrane layer have low densities, the weight of the composite copper foil can be further reduced, the weight of the solid lithium battery can be further reduced, and the manufacturing can be facilitated.
[0022] The fiber membrane layer is a PET fiber membrane layer, a PP fiber membrane layer, a PI fiber membrane layer, or a PE fiber membrane layer. Since the PET fiber membrane layer, the PP fiber membrane layer, the PI fiber membrane layer, and the PE fiber membrane layer have low densities, the weight of the composite copper foil can be further reduced, the weight of the solid lithium battery can be further reduced, and the manufacturing can be facilitated.
[0023] The pores of the porous membrane layer or the fiber membrane layer have a pore diameter of 0.05 to 500 μm and a porosity of 0.1% to 80%. By ensuring that lithium ions can pass through the pores at this value, and by providing the first metallization layer 20 and the second metallization layer 30 on both sides of the support layer 10 respectively by means of magnetron sputtering, vapor deposition, or chemical plating, it is possible to avoid clogging of the pores with metal.
[0024] The materials of both the first metallization layer 20 and the second metallization layer 30 are each a combination of one or more of cobalt, aluminum, nickel, cadmium, magnesium, lithium, and manganese. By using various combinations of metals, a dense insulating layer can be formed.
[0025] The materials of both the third metallization layer 40 and the fourth metallization layer 50 are copper or a copper alloy, and the materials of both the first conductive copper layer 60 and the second conductive copper layer 70 are copper. By adopting copper or a copper alloy for the third metallization layer 40 and the fourth metallization layer 50, when a first conductive copper layer is provided on the surface of the third metallization layer 40 away from the first metallization layer 20 and a second conductive copper layer 70 is provided on the surface of the fourth metallization layer 50 away from the second metallization layer 30 by means of electroplating or vapor deposition, the formation rates of the first conductive copper layer 60 and the second conductive copper layer 70 can be improved.
[0026] The thickness of the support layer 10 is 1 - 30 μm (micrometers), preferably 10 μm. Both the first metallization layer 20 and the second metallization layer 30 have a thickness of 5 - 100 nm (nanometers), preferably 50 nm. Both the third metallization layer 40 and the fourth metallization layer 50 have a thickness of 10 - 200 nm, preferably 100 nm. Both the first conductive copper layer 60 and the second conductive copper layer 70 have a thickness of 500 - 2000 nm, preferably 1000 nm. With such thicknesses, the total thickness of the composite copper foil of the present invention is 2.03 - 34.6 μm. Since the thickness is thin, the weight of the composite copper foil is further reduced, and the weight of the solid lithium battery is further reduced.
[0027] Referring to FIG. 2, the present invention further provides a method for manufacturing a composite copper foil for a solid lithium battery, which includes the following steps based on the above composite copper foil for a solid lithium battery.
[0028] S1. Provide the support layer 10. The width and length of the support layer 10 can be set according to the actual situation. The thickness of the support layer 10 is 1 - 30 μm. The support layer 10 is a porous membrane layer or a fiber membrane layer. The porous membrane layer is a PET porous membrane layer, a PP porous membrane layer, a PI porous membrane layer, or a PE porous membrane layer. The fiber membrane layer is a PET fiber membrane layer, a PP fiber membrane layer, a PI fiber membrane layer, or a PE fiber membrane layer. The pores of the porous membrane layer or the fiber membrane layer have a pore diameter of 0.05 - 500 μm and a porosity of 0.1% - 80%.
[0029] S2. Provide a first metallization layer 20 and a second metallization layer 30 on both sides of the support layer 10 respectively by means of magnetron sputtering, evaporation, or chemical plating. The materials of both the first metallization layer 20 and the second metallization layer 30 are each one or a combination of more than one of cobalt, aluminum, nickel, cadmium, magnesium, lithium, and manganese. Both the first metallization layer 20 and the second metallization layer 30 have a thickness of 5 - 100 nm.
[0030] S3. Provide a third metallization layer 40 on the surface of the first metallization layer 20 away from the support layer 10 and a fourth metallization layer 50 on the surface of the second metallization layer 30 away from the support layer 10 by means of magnetron sputtering, evaporation, or chemical plating. The materials of both the third metallization layer 40 and the fourth metallization layer 50 are copper or a copper alloy. Both the third metallization layer 40 and the fourth metallization layer 50 have a thickness of 10 - 200 nm.
[0031] S4. Provide a first conductive copper layer 60 on the surface of the third metallization layer 40 away from the first metallization layer 20 and a second conductive copper layer 70 on the surface of the fourth metallization layer 50 away from the second metallization layer 30 by means of electroplating or evaporation. The materials of both the first conductive copper layer 60 and the second conductive copper layer 70 are copper, and both the first conductive copper layer 60 and the second conductive copper layer 70 have a thickness of 500 - 2000 nm.
[0032] The manufacturing method of the present invention is simple in process and easy to manufacture. Since the manufactured composite copper foil is lightweight and low-cost, it reduces the weight of the solid lithium battery, reduces the manufacturing cost of the solid lithium battery, and at the same time, improves the charge and discharge speed of the solid lithium battery, greatly meeting the usage requirements.
[0033] The above is a specific description of the preferred embodiments of the present invention, but the present invention is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications and replacements without departing from the spirit of the present invention. All of these equivalent modifications or replacements are included in the scope defined by the claims of this application.
Claims
1. A three-dimensional composite copper foil for a solid lithium battery, comprising a support layer, wherein the support layer is a porous membrane layer or a fiber membrane layer, and a first metallization layer and a second metallization layer are respectively provided on both sides of the support layer, and a third metallization layer is provided on the surface of the first metallization layer away from the support layer, and a fourth metallization layer is provided on the surface of the second metallization layer away from the support layer, and a first conductive copper layer is provided on the surface of the third metallization layer away from the first metallization layer, and a second conductive copper layer is provided on the surface of the fourth metallization layer away from the second metallization layer. A three-dimensional composite copper foil for a solid lithium battery, characterized in that.
2. The three-dimensional composite copper foil for a solid lithium battery according to claim 1, wherein the porous membrane layer is a PET porous membrane layer, a PP porous membrane layer, a PI porous membrane layer or a PE porous membrane layer.
3. The three-dimensional composite copper foil for a solid lithium battery according to claim 1, wherein the fiber membrane layer is a PET fiber membrane layer, a PP fiber membrane layer, a PI fiber membrane layer or a PE fiber membrane layer.
4. The three-dimensional composite copper foil for a solid lithium battery according to claim 1, wherein the pores of the porous membrane layer or the fiber membrane layer have a pore diameter of 0.05 to 500 μm and a porosity of 0.1% to 80%.
5. The three-dimensional composite copper foil for a solid lithium battery according to claim 1, wherein the materials of the first metallization layer and the second metallization layer are both one of cobalt, aluminum, nickel, cadmium, magnesium, lithium and manganese.
6. The three-dimensional composite copper foil for a solid lithium battery according to claim 1, wherein the materials of the third metallization layer and the fourth metallization layer are both copper or copper alloy.
7. The three-dimensional composite copper foil for a solid lithium battery according to claim 1, wherein the thickness of the support layer is 1 to 30 μm.
8. The three-dimensional composite copper foil for a solid lithium battery according to claim 1, wherein the thicknesses of the first metallization layer and the second metallization layer are both 5 to 100 nm, and the thicknesses of the third metallization layer and the fourth metallization layer are both 10 to 200 nm.
9. The three-dimensional composite copper foil for a solid lithium battery according to claim 1, wherein the thicknesses of the first conductive copper layer and the second conductive copper layer are both 500 to 2000 nm.