Anode structure applied to aluminum batteries

Abstract

To provide an anode structure applicable to aluminum batteries that can improve the electric quantity, life, and performance of aluminum batteries.SOLUTION: An anode structure includes a metal substrate and a plurality of holes. The holes are located on the surface of the metal substrate. The diameter of each hole ranges from 0.05 micrometer (μm) to 500 μm.SELECTED DRAWING: Figure 1A

Description

[Technical field]

[0001] The present invention relates to a negative electrode structure applied to an aluminum battery. [Background technology]

[0002] Generally, an aluminum battery is composed of a positive electrode, a negative electrode, a separator, and an electrolyte, and the material of the negative electrode is usually a metal aluminum foil. In addition, during the process of continuous charging and discharging of the aluminum battery, the electrolyte generates electrochemical deposition on the negative electrode through oxidation and reduction. However, the metal aluminum foil is easily reactive with oxygen, resulting in the surface of the metal aluminum foil being covered with an oxide layer. In addition, the deposit after electrochemistry also covers the surface of the metal aluminum foil. Summary of the Invention [Problem to be solved by the invention]

[0003] The above-mentioned oxide layer and deposits retard the electrochemical deposition on the surface of the negative electrode, reduce the electrochemical reaction capability of the negative electrode, and further affect the electrical quantity and performance of the aluminum battery.

[0004] On the other hand, when the metal aluminum foil cannot smoothly carry out the electrochemical reaction, the electrochemical reaction is easily transferred to the separator and carried out, which causes metal deposition in the separator, and further causes the positive and negative electrodes to conduct electricity, resulting in a short circuit of the battery, thus affecting the life and performance of the battery. Therefore, how to design a better negative electrode structure and improve the electric quantity, life and performance of the aluminum battery has become a practical issue. [Means for solving the problem]

[0005] The present invention provides a negative electrode structure applied to an aluminum battery, which can improve the electric quantity, life and performance of the aluminum battery.

[0006] The negative electrode structure applied to the aluminum battery of the present invention includes a metal substrate and a plurality of holes. The holes are arranged on the surface of the metal substrate. The diameter of each hole is in the range of 0.05 micrometers (μm) to 500 μm.

[0007] In one embodiment of the invention, the material of the metal substrate comprises aluminum, nickel, copper, titanium, tin, zinc, stainless steel, alloys thereof, or combinations thereof.

[0008] In one embodiment of the present invention, the material of the metal substrate is aluminum.

[0009] In one embodiment of the invention, the pores are produced by corrosion.

[0010] In one embodiment of the invention, the pores have different sizes and the pore size is the average pore size.

[0011] In one embodiment of the present invention, the average pore size is in the range of 0.1 μm to 0.2 μm.

[0012] In one embodiment of the present invention, the material of the metal substrate is nickel.

[0013] In one embodiment of the invention, the holes are made by electroplating or electroforming deposition.

[0014] In one embodiment of the present invention, the negative electrode structure is a mesh structure.

[0015] In one embodiment of the invention, the holes have substantially the same size. Effect of the Invention

[0016] The negative electrode structure applied to the aluminum battery of the present invention can increase the reaction area of ​​the negative electrode surface and the replenishment rate of the electrolyte through the design of the holes, thus improving the electrochemical reaction capacity of the negative electrode and at the same time alleviating the problem of metal deposition in the separator, thereby improving the electric quantity, life and performance of the aluminum battery. [Brief description of the drawings]

[0017] [Figure 1A] FIG. 2 is a schematic diagram of a negative electrode structure according to one embodiment of the present invention. [Figure 1B] FIG. 2 is a schematic diagram of a negative electrode structure according to another embodiment of the present invention. [Diagram 2] 1 is a schematic diagram showing results regarding the amount of electricity in Example 1, Example 2, Comparative Example 1, and Comparative Example 2. FIG. [Diagram 3] FIG. 10 is a schematic diagram showing the results regarding the quantity of electricity in Example 3 and Comparative Example 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, embodiments of the present invention will be described in detail. However, these embodiments are merely illustrative and do not limit the present invention, which is defined by the claims.

[0019] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention can be implemented in many different forms, and therefore should not be construed as being limited to the embodiments described herein. For clarity, the sizes and thicknesses of regions, components, and layers in the drawings are not drawn to scale. For ease of understanding, the same elements are described with the same symbols in the following description.

[0020] Directional terms used herein (e.g., up, down, right, left, front, back, upper and lower) are used merely with reference to the drawings and do not imply absolute orientations.

[0021] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0022] As used herein, ranges can be expressed as from "about" one particular value to "about" another particular value, and may be directly expressed as from one particular value and / or to the other particular value. Similarly, when values ​​are expressed as approximations, the particular value is understood to form another embodiment. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

[0023] 1A and 1B are schematic diagrams of a negative electrode structure according to one embodiment of the present invention, and a negative electrode structure according to another embodiment of the present invention.

[0024] 1A and 1B, in the present invention, the negative electrode structure applied to the aluminum battery (which may be the negative electrode structure 100 of FIG. 1A or the negative electrode structure 100A of FIG. 1B) includes a metal substrate 110 and a plurality of holes 120, and the holes 120 are disposed on the surface of the metal substrate 110. Furthermore, the hole diameter of each hole 120 is in the range of 0.05 micrometers (μm) to 500 μm (e.g., 0.05 μm, 0.1 μm, 0.2 μm, 1 μm, 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 40 μm, 50 μm, or any value in the range of 0.05 μm to 50 μm). Therefore, the negative electrode structure applied to the aluminum battery of the present invention can increase the reaction area on the negative electrode surface and the replenishment rate of the electrolyte by the design of the holes 120. Therefore, the electrochemical reaction capability of the negative electrode can be improved, and at the same time, the problem of metal deposition in the separator can be alleviated, thereby improving the electric quantity, life, and performance of the aluminum battery. In addition, due to the design of the holes 120, the negative electrode structure applied to the aluminum battery of the present invention can effectively solve the problem caused by the conventional aluminum battery only using metal aluminum foil, because the ability of the electrolyte to enter the negative electrode is improved. In addition, since the electrolyte of the aluminum battery participates in the negative electrode reaction, the concentration of the electrolyte increases or decreases. When the concentration of the electrolyte on the negative electrode surface is insufficient, it affects the reaction performance. Therefore, the concentration of the electrolyte on the negative electrode surface directly affects the performance of the battery. Therefore, the holes 120 of the negative electrode structure 100 of the present invention help the electrolyte to enter the negative electrode, thereby improving the reaction capability. Therefore, compared with other batteries (e.g., lithium batteries) in which the electrolyte does not participate in the reaction, the application of the negative electrode structure 100 of the present invention to the aluminum battery can have a synergistic effect, but the present invention is not limited thereto.

[0025] It should be noted that the holes 120 shown in Figures 1A and 1B may simply be formed on the metal substrate 110 without penetrating the metal substrate 110, or may extend through the metal substrate 110 from one surface to the other.

[0026] In some embodiments, the material of the metal substrate 110 includes aluminum (Al), nickel (Ni), copper (Cu), titanium (Ti), tin (Sn), zinc (Zn), stainless steel, alloys thereof, or combinations thereof, but the present invention is not limited thereto. For example, as shown in FIG. 1A, the material of the metal substrate 110 of the negative electrode structure 100 is aluminum, and the pores 120 can be made by corrosion. Since the corrosion is based on reactivity, the pores 120 have different sizes. Thus, the pore size in the range of 0.05 μm to 500 μm refers to the average pore size (diameter) range, and the average pore size is, for example, in the range of 0.1 μm to 0.2 μm, but the present invention is not limited thereto. In another embodiment, as shown in FIG. 1B, the material of the metal substrate 110 of the negative electrode structure 100A is nickel, and the pores 120 can be made by electroforming deposition, and the negative electrode structure 100 forms a network structure. Due to the controllability of electroforming deposition, the holes 120 have substantially the same size. Thus, the hole size in the range of 0.05 μm to 500 μm refers to a single hole size (diameter) range. In some embodiments, the hole size of the holes 120 formed by electroforming deposition is, for example, in the range of 5 μm to 500 μm. It should be noted that the present invention does not limit the method of forming the holes 120. In other embodiments, the holes 120 may be made by electroplating.

[0027] In some embodiments, the shape of the holes 120 may be a circle, a square, a diamond, a hexagon, a polygon, or a combination thereof, although the invention is not limited thereto.

[0028] In some embodiments, the negative electrode structure 100 is not a multi-layer composite structure, i.e., the negative electrode structure 100 is a structure in which holes are directly drilled into the metal substrate 110, and does not combine a metal film layer with another film layer that is drilled with holes. Therefore, the negative electrode structure 100 has the advantage of a simple manufacturing process, but the present invention is not limited thereto.

[0029] It should be noted that the present invention is not limited to the above-mentioned metal substrate and holes, and the present invention does not limit other configurations of the aluminum battery (positive electrode, separator, electrolyte, etc.). Any negative electrode structure applied to an aluminum battery (electrolyte using aluminum-based ions) that includes a metal substrate and multiple holes and has a pore size (average pore size or single pore size) in the range of 0.05 μm to 500 μm is within the scope of protection of the present invention.

[0030] The effects of the present invention will be described in more detail below with reference to Examples 1 to 3 and Comparative Examples 1 to 2. In addition, the following Examples 1 to 3 will be described, but the details of the materials used, procedures, etc. may be appropriately changed without departing from the scope of the present invention. Therefore, the present invention should not be interpreted as being limited by the following Examples 1 to 3.

[0031] <Comparative Example 1>

[0032] Metallic aluminum foil was used to cut the negative electrode (thickness 0.05 millimeters (mm), size 15 mm x 25 mm) to obtain a negative electrode. Graphite slurry was applied to nickel foil (thickness 0.03 mm, size 15 mm x 25 mm) to obtain a positive electrode. Next, the negative electrode and positive electrode were arranged in order and placed in an electrolytic cell rich in electrolyte (molar ratio of ionic liquid: aluminum chloride: 1-ethyl-3-methylimidazolium chloride is 1.8:1) to obtain an aluminum battery of Comparative Example 1.

[0033] <Comparative Example 2>

[0034] The preparation method of the aluminum battery of Comparative Example 1 was the same as that of Comparative Example 1, except that the negative electrode was replaced with a titanium expansion mesh with a pore (single) diameter of 1,500 μm to obtain the aluminum battery of Comparative Example 2.

[0035] <Comparative Example 3>

[0036] A metal aluminum foil was used to cut the negative electrode (thickness 0.05 mm, size 88 mm x 148 mm). A graphite slurry was applied to nickel foil (thickness 0.03 mm, size 85 mm x 145 mm) to obtain a positive electrode. A separator was made by cutting glass fiber filter paper. Next, the negative electrode, separator, and positive electrode were arranged in order, placed in an aluminum plastic film, and then an electrolyte (the molar ratio of ionic liquid: aluminum chloride: 1-ethyl-3-methylimidazolium chloride was 1.8:1) was injected and packaged to obtain an aluminum battery of Comparative Example 3.

[0037] <Example 1>

[0038] The method for preparing the aluminum battery of Comparative Example 1 was the same as that of Comparative Example 1, except that the negative electrode was replaced with anodic aluminum oxide (AAO) (which may correspond to the structure in FIG. 1A) having an (average) pore size of 0.1 μm to 0.2 μm, thereby obtaining the aluminum battery of Example 1.

[0039] <Example 2>

[0040] The preparation method of the aluminum battery of Comparative Example 1 was the same as that of Comparative Example 1, except that the negative electrode was replaced with a nickel mesh (which may correspond to the structure of FIG. 1B ) having a (single) pore size of 27 μm to obtain the aluminum battery of Example 2.

[0041] <Example 3>

[0042] The preparation method of the aluminum battery of Comparative Example 3 was the same as that of Comparative Example 3, except that the negative electrode was replaced with AAO having a pore size of 0.1 μm to 0.2 μm to obtain the aluminum battery of Example 3.

[0043] Here, the remaining undescribed compositions and specifications of the aluminum battery can be obtained by a person skilled in the art based on any content falling within the spirit and scope of the appended claims.

[0044] FIG. 2 is a schematic diagram showing the results of the electric quantity of Example 1, Example 2, Comparative Example 1, and Comparative Example 2. FIG. 2 is a diagram showing the results of the charge / discharge tests of the aluminum batteries of Examples 1 and 2 and Comparative Examples 1 and 2, respectively, using an electrochemical workstation (BioLogic BCS-815) made by BioLogic, and the maximum discharge capacity was measured at a charge / discharge rate of 4C. FIG. 3 is a schematic diagram showing the results of the electric quantity of Example 3 and Comparative Example 3. FIG. 3 is a diagram showing the results of the charge / discharge tests of the aluminum batteries of Example 3 and Comparative Example 3, respectively, using a charge / discharge machine (CTE-BT2000-5V50A) made by Chengde Technology Co., Ltd., and the maximum discharge capacity was measured at a charge / discharge rate of 4C.

[0045] As shown in the results of FIG. 2, Examples 1, 2, and 3, which have holes on the surface of the negative electrode, can effectively improve the reaction ability of the metal negative electrode, thereby increasing the discharge capacity of the aluminum battery. In addition, compared with Comparative Example 1, Examples 1 and 2 can increase the reaction performance (electrical quantity) of the negative electrode itself by 3 to 17 times. Furthermore, as can be seen from the comparison of Examples 1 and 2 with Comparative Example 2, when the pore size of the holes in the metal negative electrode is too large, the ratio of the open area of ​​the entire material becomes too large, which reduces the reaction sites and reduces the electrical quantity. The results of FIG. 3 show that when a battery cell is formed by combining a negative electrode structure with holes with a separator, the electrical quantity of the battery cell can be increased by 15% after the reaction area of ​​the negative electrode and the replenishment rate of the electrolyte are increased. [Industrial Applicability]

[0046] The negative electrode structure applied to the aluminum battery of the present invention can increase the reaction area of ​​the negative electrode surface and the replenishment rate of the electrolyte through the design of the holes, thus improving the electrochemical reaction capacity of the negative electrode and at the same time alleviating the problem of metal deposition in the separator, thereby improving the electric quantity, life and performance of the aluminum battery. [Explanation of symbols]

[0047] 100, 100A negative electrode structure 110 Metal Substrate 120 holes

Claims

[Claim 1] A negative electrode structure applied to an aluminum battery, comprising: A metal substrate; A plurality of holes disposed on a surface of the metal substrate; wherein a pore size of each of the plurality of pores is in the range of 0.05 micrometers (μm) to 500 μm, the plurality of pores is formed by electroplating or electrochemical deposition molding, and the plurality of pores has a single pore size (diameter).

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