Method for manufacturing micro 3D current collector by using laser direct energy deposition process, and method for manufacturing 3D electrode for supercapacitor

Abstract

The present invention relates to a method for manufacturing a micro 3D current collector by using a laser direct energy deposition process, and a method for manufacturing a 3D electrode for a supercapacitor and, more specifically, to a method for manufacturing a micro 3D current collector by using a laser direct energy deposition process, by which a micro metal structure can be directly printed on a substrate by using a laser-based direct energy deposition process and utilized as a current collector for a micro supercapacitor, and a current collector having micro metal wires printed thereon not only exhibits high electrical conductivity but also provides a larger area for depositing an energy storage active material due to the large surface area of the wires.

Description

Method for manufacturing a micro 3D current collector using laser direct energy deposition and method for manufacturing a 3D electrode for a supercapacitor

[0001] The present invention relates to a method for manufacturing a micro 3D current collector using a laser direct energy deposition method and a method for manufacturing a 3D electrode for a supercapacitor.

[0002] Electrochemical capacitors represent an energy storage system between dielectric capacitors and batteries, and are attracting much attention because they have a higher energy density than conventional dielectric capacitors and a higher power density than batteries.

[0003] In particular, micro-supercapacitors are suitable as portable and lightweight power sources for small electronic devices such as micro-electromechanical systems (MEMS), small robots, wearable electronic textiles, and implantable medical devices.

[0004] In general, a supercapacitor is composed of electrode materials, electrolytes, separators, and current collectors, among which the electrode materials are the most important components and govern the overall electrochemical performance of the supercapacitor.

[0005] An ideal supercapacitor electrode material requires various properties such as high surface area, well-controlled porosity, high electrical conductivity, desirable electroactive sites, high thermal and chemical stability, and low manufacturing cost and manufacturing process.

[0006] Micrometallic structures with high electrical conductivity have diverse applications, including electrochemical electrodes, MEMS, 3D interconnectors, thermal management devices, and biomedical implants.

[0007] Micropower sources (microenergy storage devices) are in high demand for medical, biological, and environmental applications, particularly in portable and wearable electronics. Microsupercapacitors are one promising micropower source.

[0008] 3D electrodes can overcome the geometric limitations of existing 2D electrodes and thus have higher energy storage performance.

[0009] Metal current collectors are suitable for micro-supercapacitors due to their high electrical conductivity, flexibility, and good mechanical properties.

[0010] Existing multilayer coating technologies can implement 3D microelectrode structures to a limited extent, but are not practical due to the high production time and cost.

[0011] Therefore, attempts are being made to manufacture the entire body using cost-effective materials using additive manufacturing (3D printing).

[0012] Representative metal printing technologies such as SLA or SLM can create 3D microstructures in a powder bed, but have the disadvantage of being difficult to print directly on various types of substrates.

[0013] Accordingly, the present invention has been devised to solve the above-mentioned conventional problems, and the purpose of the present invention is to manufacture a micro metal wire using a laser-based direct energy deposition method.

[0014] Another object of the present invention is to fabricate a 3D current collector for a micro-supercapacitor having a high aspect ratio using a laser-based direct energy deposition method.

[0015] Another object of the present invention is to manufacture a micro-supercapacitor using a current collector processed by direct energy deposition and an electrodeposited active material.

[0016] And, according to an embodiment of the present invention, the purpose is to directly print a micro metal structure on a substrate using a laser-based direct energy deposition process and utilize it as a current collector of a micro supercapacitor.

[0017] In addition, according to an embodiment of the present invention, the purpose is to provide a method for manufacturing a micro 3D current collector using a laser direct energy deposition method, in which the current collector having printed micro metal wires not only has high electrical conductivity and aspect ratio, but also has a larger area for depositing an energy storage active material due to the large surface area of ​​the wires.

[0018] According to an embodiment of the present invention, the purpose is to provide a method for manufacturing a micro 3D current collector using a laser direct energy deposition method, which can further improve the capacity of a micro supercapacitor by electrodepositing reduced graphene oxide and polyaniline on a micro wire to provide a large active area and cause a rapid reversible redox reaction, and a method for manufacturing a 3D electrode for a supercapacitor.

[0019] Meanwhile, the technical tasks to be achieved in the present invention are not limited to the technical tasks mentioned above, and other technical tasks not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0020] The first object of the present invention can be achieved by a method for manufacturing a micro 3D metal structure using a laser direct energy deposition method, characterized in that it includes a step of printing a plurality of micro wires on a substrate using a laser direct energy deposition method.

[0021] And, before the printing step, it may be characterized by further including a step of laser cutting the substrate into an interdigital pattern or comb structure.

[0022] In addition, the laser direct energy deposition may be characterized by printing by irradiating a laser while supplying metal powder onto the substrate through a nozzle of a laser direct energy deposition system so that the length direction of the micro wire is perpendicular to the plane direction of the substrate.

[0023] And the laser direct energy deposition system may be characterized by including: a jig for fixing the substrate; a moving stage for moving the jig in the X, Y, and Z axes; a nozzle for supplying metal powder to the substrate; and a laser irradiation module for printing by irradiating a laser to the metal powder supplied on the substrate.

[0024] Additionally, the micro wire may be characterized by a diameter of 80 to 150 um and a height of 1 to 2 mm.

[0025] And the above metal powder may be characterized as a nickel-based alloy powder having a particle size of 15 to 45 μm.

[0026] The second object of the present invention can be achieved by a micro 3D metal structure characterized by being manufactured by a manufacturing method according to the first object mentioned above.

[0027] The third object of the present invention can be achieved by a micro 3D current collector characterized by having a micro 3D metal structure according to the second object mentioned above.

[0028] The fourth object of the present invention can be achieved by a method for manufacturing a micro 3D electrode, characterized in that it comprises the steps of: manufacturing a current collector through a method for manufacturing a micro 3D metal structure using a laser direct energy deposition method according to the first object mentioned above; and depositing an active material on the micro wire surface of the current collector.

[0029] And the step of depositing the active material may be characterized by including a step of depositing reduced graphene oxide and a step of depositing polyaniline.

[0030] In addition, the step of depositing the reduced graphene oxide may be characterized by electrochemically depositing the reduced graphene oxide using a three-electrode system using an aqueous suspension of graphene oxide.

[0031] And in the above three-electrode system, it can be characterized in that the current collector is used as a working electrode, the Pt mesh is used as a state electrode, and the saturated calomel electrode is used as a reference electrode.

[0032] In addition, the step of depositing the polyaniline may be characterized by polymerizing aniline using a mixed solution of sulfuric acid and aniline in a three-electrode system and electrochemically depositing the polyaniline.

[0033] And in the above three-electrode system, it can be characterized in that the electrode on which the graphene oxide is deposited is used as a working electrode, the Pt mesh is used as a state electrode, and Ag / AgCl is used as a reference electrode.

[0034] The fifth object of the present invention can be achieved by a 3D electrode for a micro supercapacitor characterized by being manufactured by a manufacturing method according to the fourth object mentioned above.

[0035] The sixth object of the present invention can be achieved by a micro-supercapacitor characterized by including a 3D electrode according to the fifth object mentioned above; and an electrolyte.

[0036] According to an embodiment of the present invention, a micro-supercapacitor can be manufactured using a micro metal wire, a 3D current collector for a micro-supercapacitor, a current collector processed by direct energy deposition, and an electrodeposited active material using a laser-based direct energy deposition method.

[0037] And according to an embodiment of the present invention, a micro metal structure can be directly printed on a substrate using a laser-based direct energy deposition process, thereby having the effect of being utilized as a current collector of a micro supercapacitor having a high aspect ratio.

[0038] In addition, according to the method for manufacturing a micro 3D current collector using a laser direct energy deposition method according to an embodiment of the present invention, the current collector having printed micro metal wires not only has high electrical conductivity and aspect ratio, but also has the effect of having a larger area for depositing an energy storage active material due to the large surface area of ​​the wires.

[0039] According to the method for manufacturing a micro 3D current collector using a laser direct energy deposition method according to an embodiment of the present invention and the method for manufacturing a 3D electrode for a supercapacitor, reduced graphene oxide and polyaniline are electrodeposited on a micro wire to provide a large active area and cause a rapid reversible redox reaction, thereby having the effect of further improving the capacity of the micro supercapacitor.

[0040] Meanwhile, the effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects that are not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0041] The following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the detailed description of the invention, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0042] Figure 1 is a flow chart of a method for manufacturing a supercapacitor having a micro 3D collector using a laser direct energy deposition method according to an embodiment of the present invention.

[0043] Figure 2 is a schematic diagram of a substrate pattern manufacturing process according to an embodiment of the present invention;

[0044] Figures 3 and 4 are schematic diagrams of a laser direct energy deposition system for producing micro wires according to an embodiment of the present invention.

[0045] Figures 5 to 7 are perspective views, enlarged views, and micro wire SEMs of a micro collector having a plurality of micro wires printed thereon according to an embodiment of the present invention.

[0046] Figure 8 is a 3D electrode on which reduced graphene oxide and polyaniline are deposited according to an embodiment of the present invention.

[0047] Figure 9 is an SEM image of reduced graphene oxide deposited on a microwire according to an embodiment of the present invention.

[0048] Figure 10 is an SEM image of polyaniline deposited on a microwire on which reduced graphene oxide is deposited according to an embodiment of the present invention.

[0049] Figure 11 is a schematic diagram of a supercapacitor using a micro 3D electrode according to an embodiment of the present invention.

[0050] Fig. 12 is a CV test graph of a supercapacitor according to an embodiment of the present invention;

[0051] Figure 13 illustrates a charge / discharge curve graph of a supercapacitor according to an embodiment of the present invention.

[0052] Hereinafter, a method for manufacturing a supercapacitor having a micro 3D collector using a laser direct energy deposition method according to an embodiment of the present invention will be described. Fig. 1 is a flowchart illustrating a method for manufacturing a supercapacitor having a micro 3D collector using a laser direct energy deposition method according to an embodiment of the present invention.

[0053] First, a method for manufacturing a 3D collector having a 3D metal structure (10) in which multiple micro wires (2) are printed will be described.

[0054] In an embodiment of the present invention, a prepared substrate (1) is laser-cut into an interdigital pattern or comb structure (S10). In a specific embodiment, a stainless steel SS316L substrate (1) is cut into an interdigital pattern or comb structure using a nanosecond pulse fiber laser.

[0055] Fig. 2 is a schematic diagram illustrating a substrate pattern manufacturing process according to an embodiment of the present invention. As illustrated in Fig. 2, cutting can be performed in an interdigital pattern, and each electrode can be designed in the shape of two fingers.

[0056] And, for the substrate (1, electrode layer) on which such a pattern is formed, a plurality of micro wires (2) are printed and deposited on the substrate (1) using a laser direct energy deposition method (S20).

[0057] FIGS. 3 and 4 illustrate schematic diagrams of a laser direct energy deposition system for manufacturing micro wires according to an embodiment of the present invention.

[0058] And FIGS. 5 to 7 show a perspective view, an enlarged view, and a micro wire SEM of a micro collector having a plurality of micro wires printed thereon according to an embodiment of the present invention.

[0059] As illustrated in FIG. 4, laser direct energy deposition is performed by irradiating a laser while supplying metal powder onto a substrate (1) through a nozzle (131) of a laser direct energy deposition system (100), thereby printing the micro wire (2) so that the longitudinal direction thereof is perpendicular to the plane direction of the substrate (1).

[0060] This laser direct energy deposition system (100) utilizes a small beam spot diameter (~22 μm) and laser modulation. The metal powder according to an embodiment of the present invention may be a nickel-based alloy powder having a spherical particle size of 15 to 45 μm. However, any metal powder capable of laser direct energy deposition may be used.

[0061] As illustrated in FIG. 4, the laser direct energy deposition system (100) includes a jig for fixing a substrate (1) and a moving stage (110) for moving the jig in the X, Y, and Z axes. In addition, the system includes a powder supply module (130) for supplying metal powder to the substrate (1), and the powder supply module (130) may be configured to include a powder supply unit (133), a pressure sensor (132) for measuring supply pressure, and a nozzle (131) for spraying metal powder.

[0062] And the laser irradiation module (120) is configured to print a micro wire (2) by irradiating a laser to a metal powder supplied on a substrate (1), and may be configured to include a laser oscillation unit (121), PBS (122), lens (123), etc.

[0063] By applying this laser direct energy deposition method, for example, 150 microwires (diameter: 110 μm, height 1.5 mm) (2) are printed on a substrate (1) to form a 3D metal interdigital collector. Nitrogen gas is supplied through a protective gas supply unit (140) to ensure powder flow and protect the printing area.

[0064] As illustrated in Fig. 6, according to an embodiment of the present invention, 150 microwires (75 microwires (2) for each electrode) having a diameter of 110 μm and a height of 1.5 mm are printed in an interdigital pattern on a substrate (1). Each electrode is designed in the shape of two fingers, and three rows of microwires (2) are evenly printed on each finger-shaped electrode.

[0065] In an embodiment of the present invention, an active material can be deposited on a micro 3D collector using the laser direct energy deposition method mentioned above.

[0066] FIG. 8 illustrates a 3D electrode on which reduced graphene oxide and polyaniline are deposited according to an embodiment of the present invention.

[0067] And FIG. 9 is an SEM showing a state in which reduced graphene oxide is deposited on a micro wire according to an embodiment of the present invention, and FIG. 10 is an SEM showing a state in which polyaniline is deposited on a micro wire on which reduced graphene oxide is deposited according to an embodiment of the present invention.

[0068] As illustrated in FIG. 8, it can be seen that the deposition of the active material according to the embodiment of the present invention may include a step (S30) of depositing reduced graphene oxide (20) and a step (S40) of depositing polyaniline (30).

[0069] Reduced graphene oxide (20) and polyaniline (30) are deposited on the microwires (2) of the current collector (10) to increase the active surface area and provide pseudocapacitor performance.

[0070] Deposition of reduced graphene oxide (20) according to an embodiment of the present invention was first performed by depositing reduced graphene oxide (20) using a three-electrode system at a potential of -1.2 V for 8 minutes using an aqueous suspension of graphene oxide (5 mg / ml) in 0.1 M LiClO4.

[0071] At this time, in the three-electrode system, the 3D printed current collector (10) is used as a working electrode, the Pt mesh is used as a counter electrode, and the saturated calomel electrode is used as a reference electrode. After the reduced graphene oxide (20) deposition process, it is washed in DI water and then dried in a convection oven at 50°C for 2 hours.

[0072] And, in the deposition of polyaniline (30) according to an embodiment of the present invention, aniline is polymerized for 10 minutes in a three-electrode system with a potential of 0.75 V using a solution of 0.5 M H2SO4 and 0.01 M aniline, and polyaniline (30) is deposited.

[0073] In the three-electrode system, the electrode on which the graphene oxide (20) from the previous step was deposited is used as a working electrode, the Pt mesh is used as a counter electrode, and Ag / AgCl (sat. KCl) is used as a reference electrode. After the polyaniline (30) deposition process, it is washed in DI water for 30 minutes and then dried.

[0074]

[0075] And a micro supercapacitor (200) is manufactured by including a 3D electrode (40) manufactured in an electrolyte (S50). Fig. 11 illustrates a schematic diagram of a supercapacitor using a micro 3D electrode according to an embodiment of the present invention.

[0076] That is, the fabricated 3D electrodes (40) are filled with a 1 M H2SO4 electrolyte to form a micro-supercapacitor (200) element and characterize its electrochemical performance.

[0077] The electrochemical performance of the micro supercapacitor (200) according to an embodiment of the present invention was tested within a potential window of 0 to 0.8 V.

[0078] FIG. 12 illustrates a CV test graph of a supercapacitor according to an embodiment of the present invention, and FIG. 13 illustrates a charge / discharge curve graph of a supercapacitor according to an embodiment of the present invention.

[0079] As illustrated in FIG. 12, it can be seen that the 3D printed micro-supercapacitor manufactured according to an embodiment of the present invention exhibits a wide CV (cyclic voltametry) graph area in a CV test.

[0080] And as shown in Fig. 13, the micro-supercapacitor device manufactured according to the embodiment of the present invention has a current density of 1 mA / cm in a 1 M H2SO4 electrolyte. 3 At 2.77 F / cm 3 It can be seen that it shows the cost-effective performance.

[0081] In addition, the devices and methods described above are not limited to the configurations and methods of the embodiments described above, and the embodiments may be configured by selectively combining all or part of each embodiment so that various modifications can be made.

Claims

1. A method for manufacturing a micro 3D metal structure, A method for manufacturing a micro 3D metal structure using a laser direct energy deposition method, characterized in that it comprises a step of printing a plurality of micro wires on a substrate using a laser direct energy deposition method.

2. In paragraph 1, Before the above printing step, A method for manufacturing a micro 3D metal structure using a laser direct energy deposition method, characterized in that it further includes a step of laser cutting the substrate into an interdigital pattern or comb structure.

3. In paragraph 2, The above laser direct energy deposition is, A method for manufacturing a micro 3D metal structure using a laser direct energy deposition method, characterized in that a laser is irradiated while supplying metal powder onto the substrate through a nozzle of a laser direct energy deposition system, thereby printing the micro wire so that the longitudinal direction thereof is perpendicular to the plane direction of the substrate.

4. In paragraph 3, A method for manufacturing a micro 3D metal structure using a laser direct energy deposition method, characterized in that the laser direct energy deposition system comprises: a jig for fixing the substrate; a moving stage for moving the jig in the X, Y, and Z axes; a nozzle for supplying metal powder to the substrate; and a laser irradiation module for printing by irradiating a laser to the metal powder supplied onto the substrate.

5. In paragraph 3, A method for manufacturing a micro 3D metal structure using a laser direct energy deposition method, characterized in that the diameter of the above micro wire is 80 to 150 um and the height is 1 to 2 mm.

6. In paragraph 3, A method for manufacturing a micro 3D metal structure using a laser direct energy deposition method, characterized in that the metal powder is a nickel-based alloy powder having a particle size of 15 to 45 μm.

7. A micro 3D metal structure characterized by being manufactured by a manufacturing method according to any one of claims 1 to 6.

8. A micro 3D current collector characterized by having a micro 3D metal structure according to Article 7.

9. A method for manufacturing a micro 3D electrode, A step of manufacturing a current collector using a method for manufacturing a micro 3D metal structure using a laser direct energy deposition method according to any one of claims 1 to 6; and A method for manufacturing a 3D electrode for a micro supercapacitor, characterized in that it comprises a step of depositing an active material on the surface of the micro wire of the above-mentioned collector.

10. In paragraph 9, The step of depositing the above active material is: A method for manufacturing a 3D electrode for a micro supercapacitor, comprising a step of depositing reduced graphene oxide and a step of depositing polyaniline.

11. In paragraph 10, The step of depositing the above reduced graphene oxide is: A method for manufacturing a 3D electrode for a micro-supercapacitor, characterized by electrochemically depositing reduced graphene oxide using a graphene oxide aqueous suspension in a three-electrode system.

12. In paragraph 11, A method for manufacturing a 3D electrode for a micro supercapacitor, characterized in that in the above three-electrode system, the current collector is used as a working electrode, the Pt mesh is used as a state electrode, and the saturated calomel electrode is used as a reference electrode.

13. In paragraph 10, The step of depositing the above polyaniline is: A method for manufacturing a 3D electrode for a micro supercapacitor, characterized by polymerizing aniline using a mixed solution of sulfuric acid and aniline and electrochemically depositing polyaniline in a three-electrode system.

14. In paragraph 13, A method for manufacturing a 3D electrode for a micro supercapacitor, characterized in that in the above three-electrode system, the electrode on which the graphene oxide is deposited is used as a working electrode, the Pt mesh is used as a state electrode, and Ag / AgCl is used as a reference electrode.

15. A 3D electrode for a micro supercapacitor characterized by being manufactured by the manufacturing method according to Article 9.

16. A micro-supercapacitor comprising a 3D electrode according to claim 15 and an electrolyte.

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