Metal-Air Battery, Power supplu comprising metal-air battery and Preparation method for metal-air battery

Abstract

A metal-air battery, a power supply device including the same, and a method for manufacturing a metal-air battery are provided, comprising: a positive electrode configured to use oxygen as a positive active material; a negative electrode current collector; a negative electrode comprising an aluminum metal extending from one end adjacent to the negative electrode current collector to another end opposing the one end; and an electrolyte between the positive electrode and the negative electrode, wherein the facing distance between the positive electrode and the aluminum metal is reduced along the extending direction of the aluminum metal.

Description

Technology Field

[0001] The invention relates to a metal-air battery, a power supply device including the same, and a method for manufacturing a metal-air battery. Background Technology

[0002] A metal-air battery comprises a negative electrode capable of dissolving metal ions during discharge, a positive electrode that reduces oxygen in the air, and an electrolyte interposed between the positive electrode and the negative electrode.

[0003] Metal-air batteries use the metal itself as the negative electrode and do not require the storage of air, the positive active material, within the battery, enabling high-capacity batteries.

[0004] The theoretical energy density per unit weight of metal-air batteries is very high, exceeding 8,100 Wh / L in aluminum-air batteries. The problem to be solved

[0005] The actual discharge capacity of a metal-air battery is less than 50% of its theoretical discharge capacity. The actual discharge capacity of a metal-air battery is reduced by side reactions such as galvanic reactions that generate hydrogen, heat loss due to overvoltage, and non-uniform electrode reactions. Non-uniform electrode reactions occur due to non-uniformity in electrode composition and non-uniformity in current density. During the discharge of a metal-air battery containing a metal anode, a relatively high current density occurs in the region adjacent to the negative electrode current collector, leading to concentrated dissolution of the metal anode in that region. As the dissolution of the metal anode proceeds in the region adjacent to the negative electrode current collector, the metal anode is severed in that area, causing a sharp drop in the capacity of the metal anode. A method is required to prevent non-uniform electrode reactions and to prevent the severing of the metal anode.

[0006] One aspect is to provide a metal-air battery with a novel structure that prevents the cutting of the metal cathode in the region adjacent to the negative current collector during discharge.

[0007] Another aspect is to provide a power supply device including the above-mentioned metal-air battery.

[0008] Another aspect is to provide a method for manufacturing the above-mentioned metal-air battery. means of solving the problem

[0009] Depending on one aspect,

[0010] A cathode configured to use oxygen as the positive active material;

[0011] A negative electrode current collector; and a negative electrode comprising an aluminum metal extending from one end adjacent to the negative electrode current collector to another end opposing the one end; and

[0012] It includes an electrolyte between the anode and the cathode, and

[0013] A metal-air battery is provided in which the facing distance between the anode and the aluminum metal is reduced along the extended direction of the aluminum metal.

[0014] Depending on the other aspect,

[0015] Metal-air battery according to the above;

[0016] An inverter that converts the DC power output from the above metal-air battery into AC power; and

[0017] A power supply unit is provided that includes an output section for outputting AC power converted by the above inverter to a load.

[0018] Depending on the other aspect,

[0019] A step of providing an anode configured to use oxygen as an active material;

[0020] A step of providing a cathode comprising a negative current collector; and an aluminum metal extending from one end adjacent to the negative current collector to another end opposite to the one end; and

[0021] The method includes the step of providing an electrolyte between the anode and the cathode, and

[0022] A method for manufacturing a metal-air battery is provided, wherein the facing distance between the anode and the aluminum metal is reduced along the extended direction of the aluminum metal. Effects of the invention

[0023] According to one aspect, a new metal-air battery is provided that can prevent the cutting of the metal negative electrode during discharge of the metal-air battery by having a new structure.

[0024] According to another aspect, a power supply is provided that provides enhanced stability by including a new metal-air battery.

[0025] According to another aspect, a method for manufacturing a new metal-air battery is provided. Brief explanation of the drawing

[0026] Figure 1 is a cross-sectional view of a metal-air battery according to one embodiment. FIG. 2 is a cross-sectional view of a metal-air battery according to one embodiment. FIG. 3 is a cross-sectional view of a metal-air battery according to one embodiment. FIG. 4 is a cross-sectional view of a metal-air battery according to one embodiment. FIG. 5 is a cross-sectional view of a metal-air battery according to one embodiment. FIG. 6 is a perspective view of a metal-air battery according to one embodiment. FIG. 7 is a perspective view of a metal-air battery according to one embodiment. FIG. 8 is a perspective view of a metal-air battery according to one embodiment. FIG. 9 is a perspective view of a metal-air battery according to one embodiment. FIG. 10 is a perspective view of a metal-air battery according to one embodiment. FIG. 11 is a perspective view of a metal-air battery according to one embodiment. FIG. 12 is a schematic diagram of a power supply device according to one embodiment. FIG. 13 is a cross-sectional view of a metal-air battery according to the prior art. FIG. 14 is a schematic diagram of a unit structure used in modeling a metal-air battery of Comparative Example 1 having the structure of FIG. 13. FIG. 15 is a schematic diagram of a unit structure used in modeling a metal-air battery of Example 1 having the structure of FIG. 1. Figure 16 is a calculation result showing the change in thickness of the negative electrode at the beginning and end of discharge of the metal-air battery of Comparative Example 1. Figure 17 is a calculation result showing the change in thickness of the negative electrode at the beginning and end of discharge of the metal-air battery of Example 1. Figure 18 is a graph comparing the change in thickness according to the distance from the negative current collector after discharge of the metal-air batteries of Comparative Example 1 and Example 1. Specific details for implementing the invention

[0027] Various embodiments are illustrated in the accompanying drawings. However, the present creative concept may be embodied in many different forms and should not be interpreted as being limited to the embodiments described herein. Rather, these embodiments are provided to ensure that the present disclosure is thorough and complete and will sufficiently convey the scope of the present creative concept to those skilled in the art. Identical reference numerals denote identical components.

[0028] When it is stated that one component is "on top" of another component, it can be understood that it may be directly on top of the other component or that another component may be interposed between them. In contrast, when it is stated that a component is "directly on top" of another component, no component is interposed between them.

[0029] Terms such as "first," "second," "third," etc., may be used in this specification to describe various components, components, regions, layers, and / or zones, but these components, components, regions, layers, and / or zones should not be limited by these terms. These terms are used solely to distinguish one component, component, region, layer, or zone from another. Accordingly, the first component, component, region, layer, or zone described below may be referred to as the second component, component, region, layer, or zone without departing from the teachings of this specification.

[0030] The terms used herein are intended to describe specific embodiments only and are not intended to limit the creative idea. The singular form used herein is intended to include the plural form including "at least one" unless the content clearly indicates otherwise. "At least one" should not be interpreted as limiting to the singular. As used herein, the term "and / or" includes any combination of one or more of the listed items. The terms "comprising" and / or "comprising" as used in the detailed description specify the presence of the specified features, regions, integers, steps, actions, components, and / or components, and do not exclude the presence or addition of one or more other features, regions, integers, steps, actions, components, components, and / or groups thereof.

[0031] Spatially relative terms such as "bottom," "lower," "subordinate," "top," "upper," and "upper" may be used herein to facilitate the description of the relationship of one component or feature to another component or feature. Spatially relative terms are to be understood as intended to include different orientations of the device during use or operation in addition to the orientations depicted in the drawings. For example, if the device in the drawings is inverted, a component described as "bottom" or "lower" of another component or feature will be oriented to the "top" of that other component or feature. Thus, the exemplary term "bottom" may encompass both the upper and lower directions. The device may be positioned in different directions (it may be rotated 90 degrees or rotated in other directions), and spatially relative terms used herein may be interpreted accordingly.

[0032] Unless otherwise defined, all terms used in this specification (including technical and scientific terms) have the same meaning as generally understood by those skilled in the art to which this disclosure pertains. Furthermore, it will also be understood that terms as defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning within the context of the relevant technology and the content of this disclosure, and should not be interpreted in an idealized or overly formal sense.

[0033] Exemplary embodiments are described herein with reference to cross-sectional views, which are schematic diagrams of idealized embodiments. As such, variations from the depicted shapes should be expected as a result of, for example, manufacturing techniques and / or tolerances. Accordingly, the embodiments described herein should not be interpreted as being limited to the specific shapes of the regions as depicted herein, but should include variations in shapes resulting from, for example, manufacturing. For example, a region depicted or described as flat may typically have rough and / or non-linear features. Furthermore, an angle depicted as sharp may be rounded. Accordingly, the regions depicted in the drawings are essentially schematic, and the shapes are not intended to depict the exact shape of the region and are not intended to limit the scope of the claims.

[0034] "Group" refers to a group of elements in the periodic table according to the International Union of Pure and Applied Chemistry ("IUPAC") group classification system of groups 1-18.

[0035] In this specification, “particle diameter” refers to the average diameter when the particle is spherical and the average major axis length when the particle is non-spherical. The particle diameter can be measured using a particle size analyzer (PSA). “Particle diameter” is, for example, the average particle diameter. The “average particle diameter” is, for example, D50, the median particle diameter.

[0036] D50 is the particle size corresponding to 50% of the cumulative volume calculated from the side of the particle with the smaller particle size in the particle size distribution measured by laser diffraction.

[0037] D90 is the particle size corresponding to the 90% cumulative volume calculated from the side of the particle with the smaller particle size in the particle size distribution measured by laser diffraction.

[0038] D10 is the particle size corresponding to the 10% cumulative volume calculated from the side of the particle with the smaller particle size in the particle size distribution measured by laser diffraction.

[0039] In the present disclosure, “metal” includes both metals and metalloids such as silicon and germanium in an elemental or ionic state.

[0040] In this disclosure, "alloy" means a mixture of two or more metals.

[0041] In the present disclosure, "anode active material" refers to an anode material comprising oxygen and a gas containing oxygen.

[0042] In the present disclosure, "cathode active material" refers to a cathode material capable of undergoing aluminumization and dealimenization.

[0043] In the present disclosure, "aluminumization" and "to aluminize" refer to the process of adding aluminum to an electrode active material.

[0044] In the present disclosure, "dealuminumization" and "dealuminumize" refer to the process of removing aluminum from an electrode active material.

[0045] In this disclosure, "charge" and "to charge" refer to the process of providing electrochemical energy to a battery.

[0046] In this disclosure, "discharge" and "discharge" refer to the process of removing electrochemical energy from a battery.

[0047] In this disclosure, "anode," "cathode," and "air electrode" refer to electrodes where electrochemical reduction occurs during the discharge process.

[0048] In this disclosure, "cathode" and "anode" refer to electrodes where electrochemical oxidation and dealilumination occur during the discharge process.

[0049] In this disclosure, "air" is not limited to atmospheric air and may include a combination of gases containing oxygen or pure oxygen gas. This broad definition of the term "air" may be applied to all uses, e.g., air batteries, air electrodes, etc.

[0050] Although specific embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are not currently anticipated or cannot be anticipated may arise to the applicant or those skilled in the art. Accordingly, the appended claims, which may be filed and modified, are intended to include all such alternatives, modifications, variations, improvements, and substantial equivalents.

[0051] A metal-air battery according to exemplary embodiments, a power supply device including the same, and a method for manufacturing a metal-air battery will be described in more detail below.

[0052] [Metal-Air Battery]

[0053] A metal-air battery according to one embodiment comprises: a positive electrode configured to use oxygen as a positive active material; a negative electrode current collector; a negative electrode comprising an aluminum metal extending from one end adjacent to the negative electrode current collector to another end opposing the one end; and an electrolyte between the positive electrode and the negative electrode. The facing distance between the positive electrode and the aluminum metal is reduced along the direction extending from the one end to the other end of the aluminum metal.

[0054] As the facing distance between the anode and the aluminum metal decreases along the direction extending from one end to the other of the aluminum metal, oxidation of the aluminum metal proceeds preferentially in the region adjacent to the other end of the aluminum metal. During the discharge of the metal-air battery, the severance between the current collector and the aluminum metal caused by the preferential oxidation of the aluminum metal in the region adjacent to one end of the aluminum metal is prevented. This prevents a rapid decrease in discharge capacity caused by the severance of the aluminum metal negative electrode during the discharge process of the metal-air battery. It also prevents a decrease in the energy density of the metal-air battery.

[0055] FIG. 1 is a cross-sectional view of a metal-air battery according to one embodiment. FIG. 2 is a perspective view of a metal-air battery according to one embodiment. FIG. 3 is a cross-sectional view of a metal-air battery according to one embodiment. FIG. 4 is a cross-sectional view of a metal-air battery according to one embodiment. FIG. 5 is a cross-sectional view of a metal-air battery according to one embodiment. FIG. 6 is a cross-sectional view of a metal-air battery according to one embodiment.

[0056] Referring to FIGS. 1 through 6, the metal-air battery (100) comprises a positive electrode (10) configured to use oxygen as a positive electrode active material. Oxygen may be supplied in the form of oxygen gas or in the form of air. During discharge, oxygen may react with water, for example, to be reduced to hydroxide ions. The voltage of the oxygen reduction reaction is about 0.4 V relative to the standard hydrogen electrode (SHE).

[0057] The cathode (20) comprises a cathode current collector (21); and an aluminum metal (22) extending from one end (EAM1) adjacent to the cathode current collector (21) to another end (EAM2) opposing the one end (EAM1). The cathode current collector (21) may be positioned, for example, on one side of the one end (EAM1) of the aluminum metal (22). The aluminum metal (22) extends from one end (EAM1), for example, one side, in contact with the cathode current collector (21), to another end (EAM2), for example, another side, opposing the one end (EAM1). The distance between the one end (EAM1) of the aluminum metal (22) and the cathode current collector (21) is smallest, and the distance between the other end (EAM2) of the aluminum metal (22) and the cathode current collector (21) is largest.

[0058] An electrolyte (30) is placed between the positive electrode (10) and the negative electrode (20). The electrolyte (30) is, for example, a liquid electrolyte.

[0059] The facing distance (FD) between the anode (10) and the aluminum metal (22) decreases along the direction (-y direction) extending from one end (EAM1) of the aluminum metal (22) to the other end (EAM2), that is, according to the distance from the negative current collector (21). By decreasing the facing distance (FD) between the anode (10) and the aluminum metal (22) along the direction (-y direction) extending from one end (EAM1) of the aluminum metal (22) to the other end (EAM2), preferential oxidation of the aluminum metal (22) can be induced in the region adjacent to the other end (EAM2) of the aluminum metal (22).

[0060] Referring to FIGS. 1 and 2, the facing distance between the anode (10) and the aluminum metal (22) is continuously reduced along the extending direction (-y direction) of the aluminum metal (22). As the facing distance between the anode (10) and the aluminum metal (22) is continuously reduced along the extending direction of the aluminum metal (22), a gradual change in the thickness of the aluminum metal (22) can be induced by the oxidation of the aluminum metal (22) during the discharge process.

[0061] Referring to FIG. 3, the facing distance between the anode (10) and the aluminum metal (22) is reduced stepwise along the extending direction (-y direction) of the aluminum metal (22). By reducing the facing distance between the anode (10) and the aluminum metal (22) stepwise along the extending direction of the aluminum metal (22), the area where oxidation of the aluminum metal (22) is concentrated can be more easily controlled during the discharge process.

[0062] Referring to FIGS. 1 through 6, there is a first distance (FD1) between the anode (10) and the aluminum metal (22) in a first region (A1) adjacent to one end (EAM1) of the aluminum metal (22). There is a second distance (FD2) between the anode (10) and the aluminum metal (22) in a second region (A2) adjacent to the other end (EAM2) of the aluminum metal (22). The first distance (FD1) is greater than the second distance (FD2). Because the first distance (FD1) is greater than the second distance (FD2), oxidation of the aluminum metal (22) in the second region (A2) can be preferentially induced.

[0063] The ratio (FD1 / FD2) of the first distance (FD1) and the second distance (FD2) may be, for example, greater than 1, 2 or more, 5 or more, or 10 or more. The ratio (FD1 / FD2) of the first distance (FD1) and the second distance (FD2) may be, for example, greater than 100, greater than 80, less than 50, or less than 30. The ratio (FD1 / FD2) of the first distance (FD1) and the second distance (FD2) may be, for example, greater than 1 to 100, 2 to 80, 5 to 50, or 10 to 30. By having the ratio (FD1 / FD2) of the first distance (FD1) and the second distance (FD2) within these ranges, oxidation of the aluminum metal (22) in the second region (A2) may be preferentially induced.

[0064] Referring to FIGS. 1 to 6, the ratio (MAXFD1 / MINFD2) of the maximum value of the first distance (MAXFD1) and the minimum value of the second distance (MINFD2) may be, for example, 2 or more, 5 or more, or 10 or more. The ratio (MAXFD1 / MINFD2) of the maximum value of the first distance (MAXFD1) and the minimum value of the second distance (MINFD2) may be, for example, 100 or less, 70 or less, 50 or less, or 30 or less. The ratio (MAXFD1 / MINFD2) of the maximum value of the first distance (MAXFD1) and the minimum value of the second distance (MINFD2) may be, for example, 2 to 100, 5 to 70, 10 to 50, or 10 to 30. As the ratio (MAXFD1 / MINFD2) of the maximum value of the first distance (MAXFD1) and the minimum value of the second distance (MINFD2) has such a range, oxidation of the aluminum metal (22) in the second region (A2) can be induced more preferentially.

[0065] Referring to FIGS. 1 through 6, the minimum value (MINFD2) of the second distance facing the anode (10) and the aluminum metal (22) may be, for example, smaller than the thickness (TAM) of the aluminum metal (22). By making the minimum value (MINFD2) of the second distance facing the anode (10) and the aluminum metal (22) smaller than, for example, the thickness (TAM) of the aluminum metal (22), the energy density of the metal-air battery (100) may be improved. The ratio (MINFD2 / TAM) of the minimum value (MINFD2) of the second distance facing the anode (10) and the aluminum metal (22) and the thickness (TAM) of the aluminum metal (22) may be, for example, 0.9 or less, 0.7 or less, 0.5 or less, 0.3 or less, or 0.1 or less. The ratio (MINFD2 / TAM) of the thickness (TAM) of the aluminum metal (22) to the minimum value (MINFD2) of the second distance facing the anode (10) and the aluminum metal (22) may be, for example, 0.001 or 0.01 or more. By having the ratio (MINFD2 / TAM) of the minimum value (MINFD2) of the second distance facing the anode (10) and the aluminum metal (22) to the thickness (TAM) of the aluminum metal (22) within this range, the energy density of the metal-air battery (100) can be further improved.

[0066] Referring to FIGS. 1 through 6, the maximum value (MAXFD1) of the first facing distance between the anode (10) and the aluminum metal (22) may be greater than the thickness (TAM) of the aluminum metal (22). By making the maximum value (MAXFD1) of the first facing distance between the anode (10) and the aluminum metal (22) greater than the thickness (TAM) of the aluminum metal (22), preferential oxidation of the aluminum metal (22) in the first region (A1) can be prevented. The ratio (MAXFD1 / TAM) of the maximum value (MAXFD1) of the first facing distance between the anode (10) and the aluminum metal (22) and the thickness (TAM) of the aluminum metal (22) may be, for example, 1.1 or greater, 1.5 or greater, 2 or greater, 3 or greater, or 5 or greater. The ratio (MAXFD1 / TAM) of the maximum value (MAXFD1) of the first distance between the anode (10) and the aluminum metal (22) and the thickness (TAM) of the aluminum metal (22) may be, for example, 100 or less, 50 or less, 30 or less, or 10 or less. By having the ratio (MAXFD1 / TAM) of the maximum value (MAXFD1) of the first distance between the anode (10) and the aluminum metal (22) and the thickness (TAM) of the aluminum metal (22) within this range, preferential oxidation of the aluminum metal (22) in the first region (A1) can be further prevented.

[0067] Referring to FIGS. 1 through 6, the aluminum metal (22) has a length (LAM) of the aluminum metal (22) from one end (EAM1) to the other end (EAM2). The aluminum metal (22) has a thickness (TAM) of the aluminum metal (22) perpendicular to the length (LAM) of the aluminum metal (22). The ratio (LAM / TAM) of the length (LAM) of the aluminum metal (22) and the thickness (TAM) of the aluminum metal (22) is, for example, 10 or more, 30 or more, 50 or more, or 100 or more. The ratio (LAM / TAM) of the length (LAM) of the aluminum metal (22) and the thickness (TAM) of the aluminum metal (22) is 10000 or less, or 1000 or less. By having the ratio (LAM / TAM) of the length (LAM) of the aluminum metal (22) and the thickness (TAM) of the aluminum metal (22) within this range, the contact area between the aluminum metal (22) and the electrolyte (30) is increased, thereby providing a high discharge current density.

[0068] Referring to FIGS. 1 through 6, the length (LAM) of the aluminum metal (22) is, for example, 5 cm or more, 10 cm or more, 50 cm or more, or 100 cm or more. Having the length (LAM) of the aluminum metal (22) within these ranges can provide increased energy density. The thickness (TAM) of the aluminum metal (22) is, for example, 10 µm or more, 100 µm or more, 500 µm or more, 1 mm or more, or 10 mm or more. Having the length (LAM) of the aluminum metal (22) within these ranges can provide increased energy density.

[0069] Referring to FIGS. 1 through 6, the facing distance between the anode (10) and the aluminum metal (22) may be, for example, 10 cm or less, 5 cm or less, 2 cm or less, or 1 cm or less. By having the facing distance between the anode (10) and the aluminum metal (22) within these ranges, an increased energy density may be provided. The facing distance between the anode (10) and the aluminum metal (22) is, for example, the maximum value of the facing distance between the anode (10) and the aluminum metal (22).

[0070] Referring to FIGS. 1 to 3 and FIG. 6, the anode (10) has a first anode thickness (TCA1) in a first region (A1) adjacent to one end (EAM1) of the aluminum metal (22). The anode (10) has a second anode thickness (TCA2) in a second region (A2) adjacent to the other end (EAM2) of the aluminum metal (22). The first anode thickness (TCA1) is smaller than the second anode thickness (TCA2). Because the first anode thickness (TCA1) is smaller than the second anode thickness (TCA2), preferential oxidation of the aluminum metal (22) in the first region (A1) can be prevented.

[0071] The ratio (TCA1 / TCA2) of the first anode thickness (TCA1) and the second anode thickness (TCA2) may be, for example, 0.9 or less, 0.7 or less, or 0.5 or less. The ratio (TCA1 / TCA2) of the first anode thickness (TCA1) and the second anode thickness (TCA2) may be, for example, 0.1 to 0.9, 0.1 to 0.7, or 0.1 to 0.5. By having the ratio (TCA1 / TCA2) of the first anode thickness (TCA1) and the second anode thickness (TCA2) within this range, preferential oxidation of the aluminum metal (22) in the first region (A1) can be prevented and preferential oxidation of the aluminum metal (22) in the second region (A2) can be induced.

[0072] Referring to FIG. 4, the anode (10) has a first anode thickness (TCA1) in a first region (A1) adjacent to one end (EAM1) of the aluminum metal (22). The anode (10) has a second anode thickness (TCA1) in a second region (A2) adjacent to the other end (EAM2) of the aluminum metal (22). The first anode thickness (TCA1) is greater than the second anode thickness (TCA2). Despite the first anode thickness (TCA1) being greater than the second anode thickness (TCA2), the first facing distance (FD1) between the anode (10) and the aluminum metal (22) in the first region (A1) is greater than the second facing distance (FD2) between the anode (10) and the aluminum metal (22) in the second region (A2). Preferential oxidation of aluminum metal (22) in the first region (A1) can be prevented by the first distance (FD1) being greater than the second distance (FD2).

[0073] The ratio (TCA1 / TCA2) of the first anode thickness (TCA1) and the second anode thickness (TCA2) may be, for example, 1.1 or more, 1.5 or more, or 2 or more. By having the ratio (TCA1 / TCA2) of the first anode thickness (TCA1) and the second anode thickness (TCA2) within this range, various types of anodes (10) can be used.

[0074] Referring to FIG. 5, the anode (10) has a first anode thickness (TCA1) in a first region (A1) adjacent to one end (EAM1) of the aluminum metal (22). The anode (10) has a second anode thickness (TCA2) in a second region (A2) adjacent to the other end (EAM2) of the aluminum metal (22). The first anode thickness (TCA1) is the same as the second anode thickness (TCA2). That the first anode thickness (TCA1) is the same as the second anode thickness (TCA2) means that the first anode thickness (TCA1) and the second anode thickness (TCA2) do not intentionally have different values. That the first anode thickness (TCA1) is the same as the second anode thickness (TCA2) means that, for example, their unintended thickness difference may be 1% or less, 0.5% or less, or 0.1% or less. The anode (10) can be manufactured more simply by having the first anode thickness (TCA1) be the same as the second anode thickness (TCA2).

[0075] FIG. 7 is a perspective view of a metal-air battery according to one embodiment. FIG. 8 is a perspective view of a metal-air battery according to one embodiment. FIG. 9 is a perspective view of a metal-air battery according to one embodiment. FIG. 10 is a perspective view of a metal-air battery according to one embodiment. FIG. 11 is a perspective view of a metal-air battery according to one embodiment.

[0076] Referring to FIGS. 1 to 4 and FIGS. 6 to 11, one surface of the anode (10) facing the aluminum metal (22) has a slope of, for example, 45 degrees or less, 40 degrees or less, 35 degrees or less, 30 degrees or less, 25 degrees or less, 20 degrees or more, 15 degrees or less, 10 degrees or less, or 5 degrees or less with respect to one surface of the aluminum metal (22) facing the anode (10). One surface of the anode (10) facing the aluminum metal (22) has a slope of, for example, greater than 0, 1 degree or more, 2 degrees or more, 3 degrees or more, or 4 degrees or more with respect to one surface of the aluminum metal (22) facing the anode (10).

[0077] One side of the anode (10) facing the aluminum metal (22) has a slope of, for example, greater than 0 to 45 degrees, 1 to 40 degrees, 1 to 35 degrees, 1 to 30 degrees, 1 to 25 degrees, 1 to 20 degrees, 1 to 15 degrees, 1 to 10 degrees, or 1 to 5 degrees with respect to one side of the aluminum metal (22) facing the anode (10). By having a slope of this range with respect to one side of the aluminum metal (22) facing the anode (10), oxidation of the aluminum metal (22) in a second region can be preferentially induced.

[0078] Referring to FIG. 5, the aluminum metal (22) and the anode (10) have a slope relative to each other, for example, 45 degrees or less, 40 degrees or less, 35 degrees or less, 30 degrees or less, 25 degrees or less, 20 degrees or more, 15 degrees or less, 10 degrees or less, or 5 degrees or less. The aluminum metal (22) and the anode (10) have a slope relative to each other, for example, greater than 0, 1 degree or more, 2 degrees or more, 3 degrees or more, or 4 degrees or more. The aluminum metal (22) and the anode (10) have a slope relative to each other, for example, greater than 0 to 45 degrees, 1 to 40 degrees, 1 to 35 degrees, 1 to 30 degrees, 1 to 25 degrees, 1 to 20 degrees, 1 to 15 degrees, 1 to 10 degrees, or 1 to 5 degrees. For example, aluminum metal (22) is positioned in a vertical direction (y-direction), and the anode (10) has an inclination with respect to the vertical direction (y-direction) of greater than 0 to 45 degrees, 1 to 40 degrees, 1 to 35 degrees, 1 to 30 degrees, 1 to 25 degrees, 1 to 20 degrees, 1 to 15 degrees, 1 to 10 degrees, or 1 to 5 degrees. By having the aluminum metal (22) and the anode (10) have an inclination within this range relative to each other, oxidation of the aluminum metal (22) can be preferentially induced in a second region. The thickness of the aluminum metal (22) may be the same as or different from the thickness of the anode (10).

[0079] Referring to FIG. 6, the thickness of the aluminum metal (22) decreases along the extending direction (-y direction) of the aluminum metal (22), that is, according to the distance from the negative current collector (21). By decreasing the thickness of the aluminum metal (22) along the extending direction (-y direction) of the aluminum metal (22), cutting due to oxidation of the aluminum metal (22) in the first region (A1) can be prevented.

[0080] In a first region (A1) adjacent to one end (EAM1) of the aluminum metal (22), the aluminum metal (22) has a first aluminum metal (22) thickness (TAM1). In a second region (A2) adjacent to the other end (EAM2) of the aluminum metal (22), the aluminum metal (22) has a second aluminum metal (22) thickness (TAM2). The first aluminum metal (22) thickness (TAM1) is greater than the second aluminum metal (22) thickness (TAM2). Because the first aluminum metal (22) thickness (TAM1) is greater than the second aluminum metal (22) thickness (TAM2), cutting of the aluminum metal (22) due to oxidation in the first region (A1) can be prevented.

[0081] The ratio (TCA1 / TCA2) of the thickness (TCA1) of the first aluminum metal (22) and the thickness (TCA2) of the second aluminum metal (22) may be, for example, greater than 1, 1.5 or greater, or 2 or greater. The ratio (TCA1 / TCA2) of the thickness (TCA1) of the first aluminum metal (22) and the thickness (TCA2) of the second aluminum metal (22) may be, for example, greater than 1 to 10, 1.5 to 10, or 2 to 10. By having the ratio (TCA1 / TCA2) of the thickness (TCA1) of the first aluminum metal (22) and the thickness (TCA2) of the second aluminum metal (22) within this range, cutting of the aluminum metal (22) due to oxidation in the first region (A1) can be prevented more effectively. The ratio (MAXTAM / MINFD2) of the maximum thickness (MAXTAM) of the aluminum metal (22) and the minimum second distance (MINFD2) facing the anode (10) and the aluminum metal (22) may be, for example, 1.1 or more, 1.5 or more, or 3 or more. The ratio (MAXTAM / MINFD2) of the maximum thickness (MAXTAM) of the aluminum metal (22) and the minimum second distance (MINFD2) facing the anode (10) and the aluminum metal (22) may be 1.1 to 10, 1.5 to 10, or 3 to 10. The ratio (MAXTAM / MINFD2) of the maximum thickness (MAXTAM) of the aluminum metal (22) and the minimum second distance (MINFD2) facing the anode (10) and the aluminum metal (22) may more effectively prevent cutting of the aluminum metal (22) due to oxidation in the first region (A1).

[0082] Referring to FIG. 7, the aluminum metal (22) has a sheet shape. The sheet-shaped aluminum metal (22) includes a first side (SS1) adjacent to the negative electrode current collector (21), a second side (SS2) facing the first side, a third side (SS3) between the first side (SS1) and the second side (SS2), and a fourth side (SS4) facing the third side (SS3). The negative electrode current collector (21) is positioned adjacent to the corners of the first side (SS1) and the third side (SS3). The positive electrode current collector (11) is positioned adjacent to, for example, the corners of the first side (SS1) and the fourth side (SS4).

[0083] The third distance (FD3) facing the anode (10) and the aluminum metal (22) in the area adjacent to the corners of the first side (SS1) and the third side (SS3) is larger than the fourth distance (FD4) facing the anode (10) and the aluminum metal (22) in the area adjacent to the corners of the first side (SS1) and the fourth side (SS3). The third distance (FD3) facing the anode (10) and the aluminum metal (22) in the area adjacent to the corners of the first side (SS1) and the third side (SS3) is larger than the fifth distance (FD5) facing the anode (10) and the aluminum metal (22) in the area adjacent to the corners of the third side (SS3) and the second side (SS2). The third distance (FD3) facing the anode (10) and the aluminum metal (22) in the area adjacent to the corners of the first side (SS1) and the third side (SS3) is larger than the sixth distance (FD6) facing the anode (10) and the aluminum metal (22) in the area adjacent to the corners of the fourth side (SS4) and the second side (SS2), for example. The fourth distance (FD4) is larger than the sixth distance (FD6), for example. The fourth distance (FD4) is larger than the fifth distance (FD5), for example. By having the metal-air battery (100) have this structure, the cutting of the aluminum metal (22) due to oxidation in the first area (A1) adjacent to the negative electrode current collector (21) can be more effectively prevented.

[0084] Referring to FIG. 8, the aluminum metal (22) has a sheet shape. The sheet-shaped aluminum metal (22) includes a first side (SS1) adjacent to the negative electrode current collector (21), a second side (SS2) facing the first side (SS1), a third side (SS3) between the first side (SS1) and the second side (SS2), and a fourth side (SS4) facing the third side (SS3). The negative electrode current collector (21) is positioned on the first side (SS1) and spaced apart from the corners of the first side (SS1) and the third side (SS3), and from the corners of the first side (SS1) and the fourth side (SS4), respectively. The distance at which the negative electrode current collector (21) is spaced apart from these multiple corners may, for example, be the same.

[0085] The seventh distance (FD7) facing the anode (10) and the aluminum metal (22) in the area adjacent to the negative electrode current collector (21) is larger than the eighth distance (FD8) facing the anode (10) and the aluminum metal (22) in the area adjacent to the corners of the first side (SS1) and the third side (SS3), for example. The seventh distance (FD7) facing the anode (10) and the aluminum metal (22) in the area adjacent to the negative electrode current collector (21) is larger than the ninth distance (FD9) facing the anode (10) and the aluminum metal (22) in the area adjacent to the corners of the first side (SS1) and the fourth side (SS4), for example. The seventh distance (FD7) facing the anode (10) and the aluminum metal (22) in the area adjacent to the negative electrode current collector (21) is larger than the tenth distance (FD10) facing the anode (10) and the aluminum metal (22) in the area adjacent to the corners of the second side (SS2) and the third side (SS3), for example. The seventh distance (FD7) facing the anode (10) and the aluminum metal (22) in the area adjacent to the negative electrode current collector (21) is larger than the eleventh distance (FD11) facing the anode (10) and the aluminum metal (22) in the area adjacent to the corners of the second side (SS2) and the fourth side (SS4), for example. The eighth distance (FD8) is larger than the tenth distance (FD10), for example. The eighth distance (FD8) is larger than the eleventh distance (FD11), for example. The ninth distance (FD9) is larger than, for example, the tenth distance (FD10). The ninth distance (FD9) is larger than, for example, the eleventh distance (FD11). By having the metal-air battery (100) have this structure, cutting due to oxidation of the aluminum metal (22) in the first region (A1) adjacent to the negative electrode current collector (21) can be more effectively prevented.

[0086] Referring to FIGS. 1 to 8, the aluminum metal (22) has a sheet-like form. The anode (10) includes a first anode (10a) facing one side of the cathode (20) and a second anode (10b) facing the other side facing one side of the cathode (20). By having the first anode (10a) and the second anode (10b) respectively placed on both sides of the cathode (20), local oxidation of the aluminum metal (22) can be prevented.

[0087] Referring to FIGS. 1 to 8, the first anode (10a) and the second anode (10b) may have a symmetrical structure with respect to the cathode (20). By having the first anode (10a) and the second anode (10b) have a symmetrical structure with respect to the cathode (20), the structural stability of the metal-air battery (100) can be further improved.

[0088] Referring to FIGS. 9 and 10, the aluminum metal (22) has a rod shape, for example. By having the aluminum metal (22) in a rod shape, the cutting of the aluminum metal (22) due to local oxidation of the aluminum metal (22) can be prevented more effectively. The anode (10) can surround, for example, the rod-shaped aluminum metal (22). The anode (10) can surround, for example, part or all of the side of the rod-shaped aluminum metal (22). By having the anode (10) surround the side of the rod-shaped aluminum metal (22), the cutting of the aluminum metal (22) due to local oxidation of the aluminum metal (22) can be prevented more effectively. The cross-section of the rod-shaped aluminum metal (22) is, for example, circular, elliptical, or polygonal. The polygon is, for example, a triangle, square, pentagon, etc., but is not limited to these.

[0089] Referring to FIGS. 9 and 10, a rod-shaped aluminum metal (22) has a length (LAM) from one end (EAM1) to the other end (EAM2) and a diameter (DAM) perpendicular to the length. The ratio (LAM / DAM) of the length (LAM) to the diameter (DAM) may be, for example, greater than 1, greater than 2, greater than 5, or greater than 10. The ratio (LAM / DAM) of the length (LAM) to the diameter (DAM) may be, for example, greater than 1 to 1000, 2 to 500, 5 to 100, or 10 to 100. By having the ratio (LAM / DAM) of the length (LAM) to the diameter (DAM) within this range, the contact area between the aluminum metal (22) and the electrolyte (30) is increased, thereby providing a high discharge current density.

[0090] Referring to FIGS. 9 and 10, in a first region (A1) adjacent to the negative electrode current collector (21), the facing distance (FD1) between the positive electrode (10) and the aluminum metal (22) is smaller than the diameter (DAM) of the aluminum metal (22). The ratio (FD1 / DAM) of the facing distance (FD1) between the positive electrode (10) and the aluminum metal (22) in the first region (A1) adjacent to the negative electrode current collector (21) and the diameter (DAM) of the aluminum metal (22) is, for example, less than 1, 0.9 or less, 0.8 or less, or 0.5 or less. By having the ratio (FD1 / DAM) of the facing distance (FD1) between the positive electrode (10) and the aluminum metal (22) in the first region (A1) adjacent to the negative electrode current collector (21) within this range, the energy density of the metal-air battery (100) is improved.

[0091] Referring to FIG. 10, the negative electrode (20) includes a plurality of rod-shaped aluminum metals (22a, 22b, 22c, 22d) that are respectively arranged adjacent to a plurality of negative current collectors (21a, 21b, 21c, 21d). The plurality of rod-shaped aluminum metals (22a, 22b, 22c, 22d) are spaced apart from each other along the width direction (z direction) of the metal-air battery (100). A plurality of negative current collectors (21a, 21b, 21c, 21d) are each electrically connected to the plurality of rod-shaped aluminum metals (22a, 22b, 22c, 22d). Although not shown in the drawing, the plurality of negative current collectors (21a, 21b, 21c, 21d) may be electrically connected to each other. Since a plurality of rod-shaped aluminum metals (22a, 22b, 22c, 22d) are spaced apart from each other along the width direction (z direction) of the metal-air battery (100), the contact area between the aluminum metals (22, 22a, 22b, 22c, 22d) and the electrolyte (30) is increased, so the current density of the metal-air battery (100) can be improved.

[0092] Referring to FIGS. 1 to 10, the anode (10) includes an anode current collector (11) and an anode active material layer (12). The anode (10) includes a first anode (10a) and a second anode (10b). The first anode (10a) includes a first anode current collector (11a) and a first anode active material layer (12a). The second anode (10b) includes a second anode current collector (11b) and a second anode active material layer (12b).

[0093] The positive active material layer (12) includes a porous material. The porous material may be a conductive material. Any porous material that is conductive may be used without limitation. The porous material may be, for example, a carbon-based material. Carbon-based materials may include, for example, carbon black, graphite, graphene, activated carbon, carbon fiber, etc. Carbon-based materials may include, for example, carbon nanoparticles, carbon nanotubes, carbon nanofibers, carbon nanosheets, carbon nanorods, carbon nanobelts, or a combination thereof. Carbon-based materials may include, for example, nanostructures, microstructures, or a combination thereof. The carbon-based material may include, for example, a microstructure having a micro-size, i.e., particles, tubes, fibers, sheets, rods, belts, or a combination thereof.

[0094] The carbon-based material may be, for example, a mesoporous carbon-based material. The carbon-based material may have porosity in a part of the material or in the entire area. By including the porous carbon-based material in the anode active material layer (12), porosity is introduced into the anode (10), thereby forming a porous anode (10). As the carbon-based material has porosity, the contact area with the electrolyte (30) may be increased. The supply and diffusion of oxygen within the anode (10) are facilitated, and a space may be provided for the dissolution of products generated during the discharge process.

[0095] Examples of conductive porous materials, such as metal fibers and metal meshes, may be used. Metallic powders such as copper, silver, nickel, and aluminum may be used as conductive materials. Organic conductive materials, such as polyphenylene derivatives, may also be used as conductive materials. The conductive materials described above may be used alone or in combination.

[0096] The positive active material layer (12) may further include one or more selected from, for example, a binder, a catalyst, and a water-repellent treatment agent.

[0097] The positive active material layer (12) may further include a binder. The binder may include, for example, a thermoplastic resin or a thermosetting resin. The binder may be used alone or in combination with, for example, polyethylene, polypropylene, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), styrene-butadiene rubber, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, vinylidene fluoride-hexafluoropropylene copolymer, vinylidene fluoride-chlorotrifluoroethylene copolymer, ethylene-tetrafluoroethylene copolymer, polychlorotrifluoroethylene, vinylidene fluoride-pentafluoropropylene copolymer, propylene-tetrafluoroethylene copolymer, ethylene-chlorotrifluoroethylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer, vinylidene fluoride-perfluoromethylvinyl ether-tetrafluoroethylene copolymer, ethylene-acrylic acid copolymer, etc., but is not necessarily limited to these, and any that can be used as a binder in the relevant technical field is possible.

[0098] The positive active material layer (12) may further include a catalyst for the oxidation / reduction of oxygen. As such a catalyst, for example, a precious metal catalyst such as platinum, gold, silver, palladium, ruthenium, rhodium, osmium; an oxide catalyst such as manganese oxide, iron oxide, cobalt oxide, nickel oxide, etc.; or an organometallic catalyst such as cobalt phthalocyanine; or a combination thereof may be used.

[0099] The catalyst described above may be supported on a carrier, for example. The carrier may be, for example, an oxide, a zeolite, a clay mineral, carbon, etc. The oxide may include one or more oxides such as alumina, silica, zirconium oxide, titanium dioxide, etc. The oxide may be an oxide containing one or more metals selected from, for example, Ce, Pr, Sm, Eu, Tb, Tm, Yb, Sb, Bi, V, Cr, Mn, Fe, Co, Ni, Cu, Nb, Mo, and W. The carbon may be, for example, carbon blacks such as Ketjen black, acetylene black, tannel black, lamp black, graphites such as natural graphite, artificial graphite, expanded graphite, activated carbon, carbon fibers, etc.

[0100] The positive active material layer (12) may further include a water-repellent treatment agent. By including the water-repellent treatment agent in the positive active material layer (12), it is possible to prevent the positive active material layer (12) from being flooded with the electrolyte (30). If the electrolyte (30) is flooded with the positive active material layer (12), the oxygen supply path may be blocked. The water-repellent treatment agent is not particularly limited as long as it has water-repellent ability, and may be, for example, a fluorine-based binder. The water-repellent treatment agent may be, for example, polytetrafluoroethylene.

[0101] The positive active material layer (12) can be manufactured by, for example, mixing the porous material, oxygen oxidation / reduction catalyst, binder, and water-repellent agent described above, and then adding a suitable solvent to prepare a positive slurry, and then coating and drying it on the surface of the positive current collector (11), or optionally by compression molding it onto the current collector to improve electrode density. As described above, a process of irradiating light after coating and drying may also be performed.

[0102] As the positive current collector (11), a porous material such as a network or mesh shape may be used to rapidly diffuse oxygen. As the positive current collector (11), a porous metal plate such as stainless steel, nickel, or aluminum may be used, but it is not necessarily limited to these, and any material that can be used as a current collector in the relevant technical field is possible. The positive current collector (11) may be coated with an oxidation-resistant metal or alloy film to prevent oxidation.

[0103] Referring to FIGS. 1 to 10, the cathode (20) includes a cathode current collector (21). The cathode current collector (21) may be, for example, copper (Cu), stainless steel, titanium (Ti), iron (Fe), cobalt (Co), nickel (Ni), indium (In), etc., but is not necessarily limited to these materials; any material used as a cathode current collector (21) in the relevant technical field is acceptable. The cathode current collector (21) may be composed of one of the metals described above, or may be composed of an alloy of two or more metals or a coating material. The cathode current collector (21) is, for example, in the form of a plate or a foil.

[0104] Referring to FIGS. 1 to 10, the electrolyte (30) comprises an alkali metal salt and a solvent. The alkali metal salt is, for example, KOH, NaOH, or LiOH. The solvent is, for example, distilled water. The concentration of the alkali metal salt is, for example, 0.1 M to 10 M.

[0105] The electrode reaction of an aluminum-air battery is as follows.

[0106] Anodic oxidation reaction: Al + 4OH - → Al(OH)4 - + 3e - (-2.38 V SHE )

[0107] Cathode reduction reaction: O2 + 2H2O + 4e - → 4OH - (0.4 V SHE )

[0108] Total cell reaction: 4Al + 3O2 + 6H2O → 4Al(OH)3

[0109] In an aluminum-air battery, electrons generated during the ionization process of the aluminum metal (22), which is the negative electrode (20), travel along a wire to the air electrode, which is the positive electrode (10), and reduce oxygen and water in the air to generate electricity.

[0110] Referring to FIG. 11, the metal-air battery (100) further includes a gas diffusion layer (40, 40a, 40b, 40c, 40d, 40e, 40f) disposed on one side of the positive electrode (10). By further including the gas diffusion layer (40, 40a, 40b, 40c, 40d, 40e, 40f) disposed on one side of the positive electrode (10), oxygen can be easily supplied to the positive electrode (10). A metal-air battery (100) comprises, for example, a plurality of unit cells (50, 50a, 50b, 50c, 50d, 50e), and the unit cells (50, 50a, 50b, 50c, 50d, 50e) comprise a negative electrode (20) and a first positive electrode (10a) and a second positive electrode (10b) disposed on both sides of the negative electrode (20). A gas diffusion layer (40, 40a, 40b, 40c, 40d, 40e, 40f) is disposed on one or more of the first positive electrode (10a) and the second positive electrode (10b) of the unit cells (50, 50a, 50b, 50c, 50d, 50e). A gas diffusion layer (40, 40a, 40b, 40c, 40d, 40e, 40f) is disposed between unit cells (50, 50a, 50b, 50c, 50d, 50e) that are arranged adjacent to each other. A gas containing oxygen, such as air, may be supplied through the gas diffusion layer (40, 40a, 40b, 40c, 40d, 40e, 40f). The gas diffusion layer (40, 40a, 40b, 40c, 40d, 40e, 40f) may be, for example, a porous conductive substrate. The gas diffusion layer (40, 40a, 40b, 40c, 40d, 40e, 40f) may simultaneously perform the role of an anode current collector (11). The gas diffusion layer (40, 40a, 40b, 40c, 40d, 40e, 40f) may be, for example, porous carbon paper, porous metal mesh, etc.

[0111] [Power supply]

[0112] FIG. 12 is a block diagram of a power supply device according to one embodiment.

[0113] A power supply unit (1000) according to one embodiment comprises: the metal-air battery (100) described above; an inverter (200) that converts the DC power output from the metal-air battery (100) into AC power; and an output unit (300) that outputs the AC power converted by the inverter (200) to a load. By including the metal-air battery (100) described above, the power supply unit (1000) can stably supply electrical energy of a constant current density or voltage without a rapid decrease in discharge capacity.

[0114] Refer to the above description for the metal-air battery (100). The inverter (200) converts the DC power output to the metal-air battery (100) into AC power. After converting the DC power into AC power, the inverter (200) applies the AC power to the output unit (300). A first switch (not shown) may be placed between the metal-air battery and the inverter (200). The first switch (not shown) may be controlled by a controller (not shown). For example, if power supply from the power supply unit (1000) is not required, the controller (not shown) may cut off the first switch (not shown). If power supply from the power supply unit is required, the controller (not shown) connects the first switch (not shown) to convert the DC power output from the metal-air battery (100) into AC power. A second switch (not shown) may be placed between the inverter and the output unit (300). The second switch (not shown) can be controlled by a controller (not shown). For example, if power supply from the power supply unit (1000) is not required, the controller (not shown) can cut off the second switch (not shown). If power supply from the power supply unit is required, the controller (not shown) connects the second switch (not shown) to apply AC power output from the inverter (200) to the output unit (300). The output unit (300) outputs AC power to the load. The power supply unit (1000) can be used, for example, as an emergency power supply unit (1000). The power supply unit (1000) including the metal-air battery (100) can provide improved energy density as it does not include a separate positive active material.

[0115] [Method for manufacturing a metal-air battery]

[0116] A method for manufacturing a metal-air battery (100) according to one embodiment comprises the steps of: providing a positive electrode (10) configured to use oxygen as an active material; providing a negative electrode current collector (21); and providing a negative electrode (20) comprising an aluminum metal (22) extending from one end (EAM1) adjacent to the negative electrode current collector (21) to another end (EAM2) opposing the one end (EAM1); and providing an electrolyte (30) between the positive electrode (10) and the negative electrode (20). The facing distance between the positive electrode (10) and the aluminum metal (22) decreases along the extending direction of the aluminum metal (22). By reducing the facing distance between the anode (10) and the aluminum metal (22) along the extended direction of the aluminum metal (22), the energy density reduction due to the disconnection of the aluminum metal (22) during the discharge of the metal-air battery can be prevented.

[0117] A positive electrode (10) configured to use oxygen as an active material is provided. The positive electrode (10) can be manufactured by, for example, by mixing a porous material, an oxygen oxidation / reduction catalyst, a binder, and a water-repellent agent, and then adding a suitable solvent to prepare a positive electrode slurry, and then coating and drying it on the surface of a positive electrode current collector (11), or optionally by compression molding it onto a current collector to improve electrode density. Specific details regarding the porous material, catalyst, binder, and water-repellent agent are referenced to the metal-air battery (100) described above.

[0118] A cathode (20) is provided. The cathode (20) comprises a cathode current collector (21); and an aluminum metal (22) extending from one end adjacent to the cathode current collector (21) to the other end opposing the one end. The cathode (20) may have a structure in which the cathode current collector (21) is connected to one side of, for example, an aluminum metal (22) sheet. A first anode (10a) and a second anode (10b) may be disposed spaced apart on both sides of the cathode (20). The first anode (10a) and the second anode (10b) may be connected to each other, for example, to form part of a container that holds an electrolyte (30).

[0119] An electrolyte (30) in the form of an aqueous solution is prepared by dissolving an alkali metal salt in distilled water. The electrolyte (30) is injected between the anode (10) and the cathode (20).

[0120] The positive electrode (10) and the negative electrode (20) are arranged such that the facing distance between the positive electrode (10) and the aluminum metal (22) is reduced along the extending direction of the aluminum metal (22). For example, the positive electrode (10) is arranged to have an inclination of 45 degrees or less with respect to the negative electrode (20) so that the facing distance between the positive electrode (10) and the negative electrode (20) in the area adjacent to the negative electrode current collector (21) is greater than the facing distance between the positive electrode (10) and the negative electrode (20) in the area furthest from the negative electrode current collector (21). This configuration may be determined by the angle between the positive electrode (10) and the negative electrode (20) or by the shape of the positive electrode (10) and / or the negative electrode (20).

[0121] The following description will be explained in detail with reference to examples and comparative examples, but is not limited to the examples below.

[0122] Evaluation Example 1: Calculation of Aluminum Cathode Thickness Change

[0123] In order to evaluate the change in thickness according to the distance of the aluminum negative electrode from the current collector during discharge of the aluminum-air battery, the aluminum-metal battery of Comparative Example 1 having the structure of Fig. 12 was modeled based on the unit structure on the left side of Fig. 13, and the aluminum-metal battery of Example 1 having the structure of Fig. 1 was modeled based on the unit structure on the left side of Fig. 14, and calculations were performed respectively using COMSOL Multiphysics® software.

[0124] The unit structure of Fig. 14 models the right half of an aluminum-air battery having the structure of Fig. 13. CA represents the positive electrode, EL represents the electrolyte, and AM represents aluminum metal.

[0125] The unit structure of Fig. 15 models the right half of an aluminum-air battery having the structure of Fig. 1. CA represents the positive electrode, EL represents the electrolyte, and AM represents aluminum metal.

[0126] The calculation results for the aluminum-metal batteries of Comparative Example 1 and Example 1 are shown in FIG. 15 and FIG. 16, respectively.

[0127] The left image in Fig. 16 shows the shape and current density distribution of the aluminum-metal negative electrode at the beginning of discharge of the aluminum-metal battery of Comparative Example 1. It was shown that at the beginning of discharge, the face-to-face distance between the aluminum metal negative electrode and the positive electrode was constant regardless of the distance from the negative current collector (not shown) connected to the top of the aluminum metal.

[0128] The image on the right in Fig. 16 shows the shape and current density distribution of the aluminum-metal negative electrode at the end of discharge of the aluminum-metal battery of Comparative Example 1. The thickness of the aluminum metal negative electrode decreased overall at the end of discharge. It was shown that at the end of discharge, the thickness of the aluminum metal negative electrode in the region adjacent to the top of the aluminum metal connected to the current collector (not shown) became thinner compared to the thickness of the aluminum metal negative electrode in the region adjacent to the bottom, which is maximally separated from the current collector (not shown).

[0129] The left image in Fig. 17 shows the shape and current density distribution of the aluminum-metal negative electrode at the beginning of discharge of the aluminum-metal battery of Example 1. It shows that at the beginning of discharge, the face-to-face distance between the aluminum metal negative electrode and the positive electrode decreases as the distance from the negative current collector (not shown) connected to the top of the aluminum metal increases.

[0130] The right side of Fig. 17 shows the shape and current density distribution of the aluminum-metal negative electrode in the late discharge phase of the aluminum-metal battery of Example 1. The thickness of the aluminum metal negative electrode decreased overall at the end of the discharge phase. It was shown that in the late discharge phase, the thickness of the aluminum metal negative electrode at the top adjacent to the current collector (not shown) became thicker compared to the thickness of the aluminum metal negative electrode at the bottom furthest from the current collector (not shown).

[0131] Figure 18 is a graph showing the thickness of the aluminum metal cathode in the later stages of discharge of the aluminum-metal cathode in Figures 16 and 17 as a function of the distance from the current collector.

[0132] As shown in Fig. 18, the aluminum-metal battery of Example 1 demonstrated that as the distance from the negative current collector increased after discharge, the thickness of the aluminum metal negative electrode decreased, allowing for stable discharge without cutting the aluminum metal negative electrode.

[0133] In contrast, the aluminum-metal battery of Comparative Example 1 showed that as the distance from the negative current collector decreased after discharge, the thickness of the aluminum metal negative electrode decreased, increasing the possibility of the aluminum metal negative electrode being cut.

[0134] Although an exemplary embodiment has been described above, it is not limited thereto. It is possible to implement the invention with various modifications within the scope of the claims, the detailed description of the invention, and the attached drawings, and it is obvious that such modifications also fall within the scope of the invention. Explanation of the symbols

[0135] 10 anodes 10a First anode 10b Second anode 11 positive current collector 11a First positive current collector 11b Second positive current collector 12 positive electrode active material layer 12a First positive active material layer 12b Second positive active material layer 20 cathodes 21, 21a, 21b, 21c, 21d cathode current collector 22, 22a, 22b, 22c, 22d Aluminum metal 30 electrolytes 40, 40a, 40b, 40c, 40d, 40e, 40f gas diffusion layer 50, 50a, 50b, 50c, 50d, 50e unit cell 100 metal-air batteries 200 inverter 300 output section 1000 power supply

Claims

Claim 1 A metal-air battery comprising: a positive electrode configured to use oxygen as a positive active material; a negative electrode current collector; a negative electrode comprising an aluminum metal extending from one end adjacent to the negative electrode current collector to another end opposing the one end; and an electrolyte between the positive electrode and the negative electrode, wherein the facing distance between the positive electrode and the aluminum metal is reduced along the extending direction of the aluminum metal. Claim 2 A metal-air battery according to claim 1, wherein the facing distance between the anode and the aluminum metal along the extending direction of the aluminum metal decreases continuously or stepwise. Claim 3 A metal-air battery according to claim 1, having a first distance (FD1) facing between the anode and the aluminum metal in a first region (A1) adjacent to one end of the aluminum metal, and a second distance (FD2) facing between the anode and the aluminum metal in a second region (A2) adjacent to the other end of the aluminum metal, wherein the first distance (FD1) is greater than the second distance (FD2). Claim 4 A metal-air battery according to claim 3, wherein the ratio (FD1 / FD2) of the first distance (FD1) and the second distance (FD2) is greater than 1 and less than or equal to 100. Claim 5 A metal-air battery according to claim 3, wherein the minimum value (MINFD2) of the second distance facing the anode and the aluminum metal is smaller than the thickness (TAM) of the aluminum metal, and the ratio (MINFD2 / TAM) of the minimum value (MINFD2) of the second distance facing the anode and the aluminum metal to the thickness (TAM) of the aluminum metal is 0.9 or less. Claim 6 A metal-air battery according to claim 3, wherein the maximum value (MAXFD1) of the first facing distance between the anode and the aluminum metal is greater than the thickness (TAM) of the aluminum metal, and the ratio (MAXFD1 / TAM) of the maximum value (MAXFD1) of the first facing distance between the anode and the aluminum metal and the thickness (TAM) of the aluminum metal is 1.1 or greater. Claim 7 A metal-air battery according to claim 1, wherein the aluminum metal has a length (LAM) from one end to the other end and a thickness (TAM) perpendicular to the length, and the ratio (LAM / TAM) of the length (LAM) to the thickness (TAM) is 10 or more. Claim 8 A metal-air battery according to claim 1, wherein the length (LAM) of the aluminum metal is 10 cm or more, the thickness (TAM) of the aluminum metal is 100 μm or more, and the facing distance between the anode and the aluminum metal is 10 cm or less. Claim 9 A metal-air battery according to claim 1, wherein the anode has a first anode thickness (TCA1) in a first region (A1) adjacent to one end of the aluminum metal, and the anode has a second anode thickness (TCA2) in a second region (A2) adjacent to the other end of the aluminum metal, and the first anode thickness (TCA1) is smaller than the second anode thickness (TCA2). Claim 10 A metal-air battery according to claim 9, wherein the ratio (TCA1 / TCA2) of the first anode thickness (TCA1) and the second anode thickness (TCA2) is 0.9 or less. Claim 11 A metal-air battery according to claim 1, wherein the anode has a first anode thickness (TCA1) in a first region (A1) adjacent to one end of the aluminum metal, and the anode has a second anode thickness (TCA1) in a second region (A2) adjacent to the other end of the aluminum metal, and the first anode thickness (TCA1) is greater than the second anode thickness (TCA2). Claim 12 A metal-air battery according to claim 1, wherein one surface of the anode facing the aluminum metal has an inclination of 45 degrees or less with respect to one surface of the aluminum metal facing the anode. Claim 13 A metal-air battery according to claim 1, wherein the aluminum metal has a sheet form, and the sheet includes a first side (SS1) adjacent to the negative electrode current collector, a second side (SS2) opposite the first side, a third side (SS3) between the first side (SS1) and the second side (SS2), and a fourth side (SS4) opposite the third side (SS3), and wherein the negative electrode current collector is positioned adjacent to the corners of the first side (SS1) and the third side (SS3). Claim 14 A metal-air battery according to claim 1, wherein the aluminum metal has a sheet form, and the sheet includes a first side (SS1) adjacent to the negative electrode current collector, a second side (SS2) facing the first side (SS1), a third side (SS3) between the first side (SS1) and the second side (SS2), and a fourth side (SS4) facing the third side (SS3), and the negative electrode current collector is disposed on the first side (SS1) spaced apart from the corners of the first side (SS1) and the third side (SS3) and the corners of the first side (SS1) and the fourth side (SS4), respectively. Claim 15 A metal-air battery according to claim 1, wherein the aluminum metal has a sheet-like form, and the positive electrode comprises a first positive electrode facing one side of the negative electrode and a second positive electrode facing the other side facing the one side. Claim 16 A metal-air battery according to claim 15, wherein the first anode and the second anode have a symmetric structure with respect to the cathode. Claim 17 A metal-air battery according to claim 1, wherein the aluminum metal has a rod shape and the positive electrode surrounds the aluminum metal. Claim 18 A metal-air battery according to claim 1, further comprising a gas diffusion layer disposed on one surface of the anode. Claim 19 A power supply device comprising: a metal-air battery according to any one of claims 1 to 18; an inverter that converts a DC power output from the metal-air battery into an AC power; and an output unit that outputs the AC power converted by the inverter to a load. Claim 20 A method for manufacturing a metal-air battery comprising: providing a positive electrode configured to use oxygen as an active material; a negative electrode current collector; and providing a negative electrode comprising an aluminum metal extending from one end adjacent to the negative electrode current collector to another end opposing the one end; and providing an electrolyte between the positive electrode and the negative electrode, wherein the facing distance between the positive electrode and the aluminum metal is reduced along the extending direction of the aluminum metal.

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