LITHIUM-AIR BATTERY

Abstract

A lithium-air battery comprising a plurality of unit cells (20) of different diameters, each unit cell (20) comprising: Electrodes (26), comprising: a disc-shaped positive electrode (22) having a first air flow path (22-1) passing through the positive electrode (22) in the vertical direction of the lithium-air battery, and one or more electrolyte flow paths (22-2) on the positive electrode (22) in the horizontal or vertical direction of the lithium-air battery; and a negative electrode (24) having a second air flow path (24-1) passing through the negative electrode (24) in the vertical direction and coinciding with the first air flow path (22-1), and a separator (28) arranged between the positive electrode (22) and the negative electrode (24), wherein the unit cells (20) are stacked in the vertical direction within a stacked cell container (10) such that a diffusion layer (30) is arranged between the respective unit cells (20), and a lowest unit cell (20) has the largest diameter and the diameters of the remaining unit cells (20) stacked one after the other on the lowest unit cell (20) gradually decrease vertically upwards, so that the unit cells (20) have a stepped structure.

Description

TECHNICAL FIELD

[0001] The present invention relates to a lithium-air battery. More particularly, the present invention relates to a lithium-air battery having a novel structure in which the cells of the units are stacked in a stepped structure using disc electrodes with radial and vertical flow paths. BACKGROUND

[0002] In general, a lithium-air battery is considered a secondary battery whose charging and discharging occurs through electrochemical reaction between lithium and oxygen.

[0003] The lithium-air battery includes a plurality of stacked unit cells, each unit cell includes electrodes including an air electrode, i.e., a positive electrode, and a negative electrode formed of lithium, and a separator formed of a material that allows the passage of a liquid electrolyte and disposed between the positive electrode and the negative electrode, and a diffusion layer that uniformly diffuses air and the electrolyte disposed between the respective cells.

[0004] Therefore, when the lithium-air battery is discharged, lithium ions moving from the negative electrode to the positive electrode and oxygen supplied to the positive electrode react with each other at a surface of the positive electrode to produce lithium oxide on the surface of the positive electrode.

[0005] The conventional lithium-air battery is known to have problems as described below. (1) Evaporation and depletion of electrolytes

[0006] When charging and discharging a lithium-air battery, a three-phase reaction occurs in which lithium ions, electrons, and oxygen meet and react at a single point. Since the lithium ions are supplied from an electrolyte, the electrons from the electrode, and the oxygen are supplied from the outside, the electrolyte is inevitably exposed to oxygen.

[0007] Therefore, the electrolyte is volatile and thus volatilization of the electrolyte occurs, and the electrolyte generates gas and becomes depleted because the electrolyte is subjected to a strong oxidation-reduction potential at the positive electrode and the negative electrode during the charge and discharge reaction.

[0008] As a result, the electrolyte is evaporated and exhausted during the charging and discharging process of the lithium-air battery, so that the use of the lithium-air battery is limited. (2) Application of low oxygen partial pressure

[0009] During the charging and discharging process of the lithium-air battery, oxygen must be supplied to the positive electrode in a 3-phase reaction and serve as the active material.

[0010] Increasing the partial pressure of oxygen used as the active material reduces the reaction resistance generated during the discharge reaction, thus increasing the reaction efficiency. However, since a battery pack capable of greatly increasing the oxygen partial pressure in the manufacture of a lithium-air battery with multiple stacked cells has not yet been developed, there is no choice but to use a low oxygen partial pressure for the charging and discharging process. (3) Difficulties in oxygen diffusion in the oxygen diffusion layer

[0011] Since oxygen is used as the active material in the lithium-air battery and a uniform reaction is required for long cell life, a uniform oxygen supply per unit area of the electrode is required.

[0012] Therefore, the lithium-air battery solves the problem of oxygen diffusion during the reaction by using a gas diffusion layer (GDL) as an oxygen diffusion layer or a porous support as a support for the positive electrode active material. However, with a large-area electrode, the difficulty of uniform oxygen diffusion is not solved, so additional oxygen flow paths are required.

[0013] Incidentally, fully electrically rechargeable metal anode battery systems and methods for producing such systems are known from US 2015 / 0 010 833 A1. An electrically rechargeable metal anode cell may comprise a metal electrode, an air-contact electrode, and an aqueous electrolyte separating the metal electrode and the air-contact electrode. In some embodiments, the metal electrode may be in direct contact with the liquid electrolyte, and no separator or porous membrane is required between the air-contact electrode and the electrolyte. Rechargeable metal anode cells may be electrically connected to one another via a centrode junction, in which a metal electrode of one cell and an air-contact electrode of a second cell are electrically connected. Air tunnels or channels may be provided between individual metal anode cells arranged in a stack.Embodiments may provide an electrolyte flow management system to maintain the liquid electrolyte at a constant level during charge and discharge cycles.

[0014] EP 2 586 092 B1 discloses an electrochemical cell comprising a fuel electrode comprising a series of permeable electrode bodies arranged at a distance from one another, and an oxidant electrode spaced from the fuel electrode. A charging electrode is spaced from the fuel electrode. The charging electrode is selected from the group consisting of (a) the oxidant electrode and (b) a separate charging electrode. That is, the charging electrode can be the oxidant electrode or a third electrode in the system. An ionically conductive medium transfers ions between the electrodes. The ions can be in free ionic form or in molecular or complexed form. The series of permeable electrode bodies comprises a proximal permeable electrode body located proximal to the charging electrode and a distal permeable electrode body located distal to the charging electrode.Along at least a portion of a peripheral edge of the fuel electrode, an edge of the proximal permeable electrode body is located within an edge of the distal permeable electrode body.

[0015] WO 2013 / 080 968 A1 proposes a water-activated air cell comprising air cell-forming bodies that generate electricity by injecting an electrolyte, and a reservoir for storing an electrolyte that is fed into the air cell-forming bodies. The reservoir is arranged within the air cell-forming bodies.

[0016] Furthermore, WO 2013 / 084806 A1 also discloses an air battery with a power generation unit having a negative electrode and a positive electrode that abut each other at predetermined intervals; and an electrolyte reservoir that stores electrolyte for supply to this power generation unit. The ah* battery has an electrolyte diffusion channel formed in the facing surface of the negative electrode or the positive electrode, or in both facing surfaces, for diffusion and permeation of the electrolyte from the electrolyte reservoir into all areas of the power generation unit. OVERVIEW OF THE INVENTION

[0017] The present invention has been made in an effort to solve the above-described problems associated with the prior art, and it is an object of the present invention to provide a lithium-air battery that can minimize volatilization and depletion of an electrolyte during a charging and discharging process, uniformly diffuse and supply the electrolyte to an electrode, and increase a partial pressure of oxygen as an active material during the charging and discharging process to effectively supply oxygen to a positive electrode and achieve uniform oxygen supply per unit area of the electrode.

[0018] The problem is solved by a lithium-air battery having the features of claim 1. Advantageous further developments can be found in the subclaims.

[0019] In one aspect, the present invention provides a lithium-air battery having a plurality of unit cells with different diameters, each unit cell comprising electrodes having a disc-shaped positive electrode having a first air flow path extending vertically through the lithium-air battery, and one or more electrolyte flow paths on the positive electrode in the horizontal or vertical direction of the lithium-air battery, and a negative electrode having a second air flow path passing vertically therethrough and coinciding with the first air flow path, and a separator disposed between the positive electrode and the negative electrode, wherein the unit cells are stacked vertically within a stacked cell container such that a diffusion layer is disposed between the respective unit cells,and the lowest unit cell has the largest diameter and the diameters of the unit cells sequentially stacked on the lowest unit cell gradually decrease in the ascending direction, so that the unit cells have a graded structure.

[0020] A supplementary separator surrounding and protecting the negative electrode at its periphery may extend from a portion of the outer diameter of the separator.

[0021] The positive electrode may be formed to have a disk shape having the first air flow path formed through its center in the vertical direction and a plurality of electrolyte flow paths formed on one surface thereof as grooves extending in the horizontal direction from the first air flow path to the edge of the positive electrode and arranged radially.

[0022] The positive electrode may be formed to have an umbrella shape having the first air flow path formed through its center in the vertical direction and an electrolyte flow path formed as a part of the positive electrode, which is inclined downward at a certain angle from the first air flow path to the edge of the positive electrode.

[0023] The positive electrode may be formed to have a disk shape having the first air flow path formed through its center in the vertical direction and a plurality of electrolyte flow paths formed through the positive electrode in the vertical direction throughout the entire length of the positive electrode from the first air flow path to the edge of the positive electrode.

[0024] The positive electrode may have a structure including a plurality of concentric discs having different diameters provided with the first air flow path formed by the center of the concentric disc located in a central region of the positive electrode in the vertical direction, and a plurality of electrolyte flow paths formed as separation spaces between the respective concentric discs in the vertical direction.

[0025] The negative electrode may be formed to have a disk shape provided with the second air flow path formed through its center in the vertical direction.

[0026] An oxygen supply line connected to a separate oxygen supply tank and an electrolyte supply line connected to a separate electrolyte tank may be connected to an inlet of the stacked cell tank, and a nozzle connected to the end of the electrolyte supply line for spraying the electrolyte evenly over the entire surface of an electrode may be installed on the stacked cell tank.

[0027] An oxygen supply line connected to an oxygen supply tank may be connected to an inlet of the stacked cell tank, an electrolyte tank may be installed in an upper portion of the interior of the stacked cell tank, and nozzles for uniformly spraying the electrolyte over the entire surface of an electrode may be installed at outlets of the electrolyte tank installed in the upper portion of the interior of the stacked cell tank.

[0028] A recirculation line for returning the electrolyte may be connected between a lower portion of the interior of the stacked cell container and the electrolyte tank, and a recirculation pump may be arranged on the recirculation line.

[0029] An electrolyte refill line can be connected to the recirculation line.

[0030] Ventilation valves can be installed on the upper and lower parts of the stacked cell container to ensure the necessary oxygen extraction.

[0031] The stacked cell vessel can be equipped with a structure corresponding to a shape of a hollow cylinder with hemispherical ends to meet the conditions for high pressure processes.

[0032] Other aspects and preferred embodiments of the invention are discussed below. SHORT DESCRIPTION OF THE DRAWING FIGURES

[0033] The above and other features of the present invention will now be described in detail with reference to some exemplary embodiments illustrated in the accompanying drawing figures, which are given below for illustrative purposes only and thus do not constitute a limitation of the present invention, wherein: Fig. 1 is a cross-sectional view illustrating an example of a lithium-air battery in which the single cells are stacked according to the present invention; Fig. 2A to 2D are perspective views illustrating positive electrodes of a lithium-air battery in accordance with embodiments of the present invention; Fig. 3 is a view illustrating a lithium-air battery according to an embodiment of the present invention; and Fig. 4 is a view illustrating a lithium-air battery according to another embodiment of the present invention.

[0034] It should be understood that the accompanying drawing figures are not necessarily to scale and represent a somewhat simplified representation of various preferred features illustrating the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, positions, and shapes, will be determined in part by the particular intended application and use environment.

[0035] In the figures, like reference numerals refer to the same or equivalent parts of the present invention in the different figures of the drawing. DETAILED DESCRIPTION

[0036] In the following, reference will now be made in detail to various embodiments of the present invention, which are illustrated by way of example in the accompanying drawing figures and described below.

[0037] Fig. Figure 1 shows a sectional view illustrating an exemplary lithium-air battery in which the individual cells are stacked according to the present invention. Numeral 10 indicates a stacked cell container.

[0038] The stacked cell container 10 is a container in which the cells of the lithium-air battery are stacked and installed, and has a hollow cylindrical structure with semicircular top and bottom surfaces in cross section to meet the conditions of the high pressure process (e.g., normal pressure - 10 bar) for the charging and discharging reaction of the battery.

[0039] According to the present invention, as exemplified in Fig. 1, the unit cells 20 are stacked in a step structure within the stacked cell container 10.

[0040] Each unit cell 20 contains electrodes 26 comprising an air electrode, i.e., a positive electrode 22, and a negative electrode 24 made of lithium, and a separator 28 formed of a material that transfers a liquid electrolyte and is arranged between the positive electrode 22 and the negative electrode 24.

[0041] In particular, the positive electrode 22 and the negative electrode 24 of the electrodes 26 have disc shapes with different diameters.

[0042] Here, a first air flow path 22-1 in the vertical direction is formed by the positive electrode 22 of the electrodes 26 and at the same time one or more electrolyte flow paths 22-2 in the horizontal or vertical direction are formed on the positive electrode 22, and a second air flow path 24-1 in the vertical direction is formed by the negative electrode 24, which coincides with the first air flow path 22-1.

[0043] Therefore, the unit cells 20, each formed by sequentially stacking the positive electrode 22, the separator 28, and the negative electrode 24, are stacked vertically in the stacked cell tank 10, and a diffusion layer 30 is disposed between the respective unit cells 20.

[0044] In particular, when stacking the unit cells 20, the electrodes 26 having the largest diameter are arranged at the lowest position, and thereafter, the diameters of the stacked electrodes 26 are gradually reduced toward the top.

[0045] Therefore, when the unit cells 20 according to the present invention are stacked vertically in the stacked cell container 10, the unit cells 20 are stacked such that the unit cell 20 located at the lowest position has the largest diameter, and thereafter, the diameters of the unit cells 20 gradually decrease upwards to form a stepped structure.

[0046] The positive electrode 22 of the electrodes 26 may have a disk shape by which the first air flow path 22-1 is formed in the vertical direction and on which one or more different electrolyte flow paths 22-2 are formed in the horizontal or vertical direction, and the negative electrode 24 may be configured to have a disk shape by which the second air flow path 24-1 is formed in the vertical direction, which coincides with the first air flow path 22-1.

[0047] Referring to the Fig. 2A, a positive electrode 22 may have a disk shape with a first air flow path 22-1 in the vertical direction formed through its center and a plurality of electrolyte flow paths 22-2 formed as grooves extending in the horizontal direction from the first air flow path 22-1 to the edge of the positive electrode 22 and arranged radially.

[0048] Therefore, oxygen supplied from an oxygen supply source flows downwardly along the first air flow path 22-1, and electrolyte supplied from an electrolyte supply source flows outwardly of the positive electrode 22 along the groove-shaped electrolyte flow paths 22-2.

[0049] With reference to Fig. 2B, a positive electrode 22 may have an umbrella shape provided with a first air flow path 22-1 in the vertical direction formed through its center, so that the positive electrode 22 is inclined downward at a certain angle from the first air flow path 22-1 to the edge of the positive electrode 22, and such a downwardly inclined part of the positive electrode 22 serves as an electrolyte flow path 22-2 along which an electrolyte can flow in the downward direction.

[0050] Therefore, the oxygen supplied from an oxygen supply source flows downwardly along the first air flow path 22-1, and the electrolyte supplied from an electrolyte supply source flows along the downwardly inclined electrolyte flow path 22-2 to a next lower unit cell.

[0051] With reference to Fig. 2c, a positive electrode 22 may have a disk shape provided with a first air flow path 22-1 in the vertical direction formed through its center, and a plurality of electrolyte flow paths 22-2 formed as holes formed through the positive electrode 22 in the vertical direction and irregularly arranged over the entirety of the positive electrode 22 from the first air flow path 22-1 to the edge of the positive electrode 22.

[0052] Therefore, oxygen supplied from an oxygen supply source flows downward along the first air flow path 22-1, and an electrolyte supplied from an electrolyte supply source falls along the hole-shaped electrolyte flow paths 22-2 to a next lower unit cell.

[0053] Here, the hole-shaped electrolyte flow paths 22-2 are irregularly arranged so that the electrolyte can fall onto the surface of an electrode of the next lower unit cell and evenly soak the surface of the electrode to facilitate the charging and discharging reaction.

[0054] With a view to Fig. 2D, a positive electrode 22 may have a structure in which a plurality of concentric disks having different diameters are arranged, a first air flow path 22-1 is formed in the vertical direction through the center of the concentric disk located in the central region of the positive electrode 22, and separation spaces between the respective concentric disks serve as electrolyte flow paths 22 in the vertical direction.

[0055] Therefore, oxygen supplied from an oxygen supply source flows downward along the first air flow path 22-1, and an electrolyte supplied from an electrolyte supply source falls to a next lower unit cell along the electrolyte flow paths 22-2.

[0056] Each of the unit cells 20 stacked in the stacked cell container 10 includes the separator 28 disposed between the positive electrode 22 and the negative electrode 24, and a supplementary separator 28-1 bent vertically downward is formed at an outer diameter part of the separator 28.

[0057] That is, the supplemental separator 28-1, which surrounds and protects the periphery of the negative electrode 24, extends from the outer diameter part of the separator 28.

[0058] Therefore, when an electrolyte exceeding a retainable amount is supplied to the unit cells 20, the electrolyte supplied to the unit cell 20 remains on the outer surface of the supplementary separator 28-1 and then naturally drops to the next lower unit cell 20, whereby the functions of smoothly supplying and dispersing the electrolyte to the respective unit cells 20 can be improved.

[0059] Since the supplementary separator 28-1 surrounds the periphery of the negative electrode 24 made of lithium and thus protects the negative electrode 24, the supplementary separator 28-1 can block the direct contact between oxygen and lithium and thus prevent the oxidation of lithium.

[0060] Now on the Fig. 3, an oxygen supply line 42 connected to a separate oxygen storage tank 40 and an electrolyte supply line 52 connected to a separate electrolyte tank 50 are connected to an inlet formed at an upper part of the stacked cell container 10.

[0061] A nozzle 54 connected to the end of the electrolyte supply line 54 is arranged on the stacked cell container 10, and the nozzle 54 serves to spray the electrolyte evenly over the entire surface of an electrode (ie, the surface of the positive electrode 22 of the uppermost unit cell 20).

[0062] Otherwise, as in Fig. 4, an oxygen supply line 42 connected to an oxygen storage tank 40 may be connected to an inlet formed at an upper part of the stacked cell container 10, and an electrolyte tank 50 may be formed or arranged directly at an upper portion of the interior of the stacked cell container 10.

[0063] The nozzles 54 are arranged at the positions of the outlets of the electrolyte tank 50 installed in the upper portion of the interior of the stacked cell container 10, and the nozzles 54 also serve to spray the electrolyte evenly over the entire surface of an electrode (ie, the surface of the positive electrode 22 of the uppermost unit cell 20).

[0064] When the electrolyte tank 50 is formed or arranged directly on or within the upper portion of the interior of the stacked cell tank 10, a recirculation line 56 for recirculating the electrolyte is connected between a lower portion of the interior of the stacked cell tank 10 and the electrolyte tank 50, and a recirculation pump 58 for recirculating the electrolyte is mounted on the recirculation line 56.

[0065] If the electrolyte tank 50 is formed or installed directly on or within the upper portion of the interior of the stacked cell container 10, the electrolyte tank 50 is in a closed state, and it is difficult to replenish the electrolyte in the electrolyte tank 50. Therefore, a separate electrolyte replenishment line 60 is connected to the recirculation line 56.

[0066] When the electrolyte is replenished via the electrolyte replenishing pipe 60, the electrolyte can easily refill the electrolyte tank 50 formed directly at or in the upper portion of the interior of the stacked cell container 10, thus preventing electrolyte suction.

[0067] Ventilation valves 62 are arranged in the upper and lower parts of the stacked cell container 10 for the mandatory removal of gases or oxygen.

[0068] Therefore, when the lithium-air battery cells 20 stacked in the stacked cell container 10 undergo a charge or discharge reaction, and when it is necessary to discharge the exhaust gas generated by the reaction or when it is necessary to urgently discharge oxygen to the outside in case of a malfunction of the battery cells 20, the vent valves 62 can be opened, whereby gas or oxygen can be easily discharged from the stacked cell container 10 to the outside.

[0069] The following describes a charging and discharging current of the lithium-air battery described above.

[0070] First, oxygen is supplied from the oxygen storage tank 40 along the oxygen supply line 42 to the inlet of the stacked cell container 10 and, at the same time, an electrolyte from the electrolyte tank 50 is supplied to the interior of the stacked cell container 10.

[0071] The oxygen supplied to the interior of the stacked cell container 10 moves along the first and second air flow paths 22-1 and 24-1 in the vertical direction formed at the respective unit cells 20, and penetrates the diffusion layers 30 and also penetrates the positive electrode 22 of the uppermost unit cell 20.

[0072] At the same time, the electrolyte is sprayed evenly over the entire surface of an electrode (the surface of the positive electrode 22 of the uppermost unit cell 20) through the nozzle 54.

[0073] Then, as above with a view of the Fig. 2A to 2D, the electrolyte flows along the electrolyte flow paths 22-2 of the respective positive electrodes 22 and sags from the uppermost unit cell 20 to the next lower unit cell 20 in the downward direction.

[0074] Here, the electrolyte remains on the outer surface of the supplementary separator 28-1 formed at the outer diameter part of the separator 28 and then naturally sags to the next lower unit cell 20, whereby the functions of smoothly supplying and dispersing the electrolyte to the respective unit cells 20 can be improved.

[0075] As described above, electrolyte and oxygen can be easily supplied to the respective unit cells stacked in a stepped structure, so that when the lithium-air battery is discharged, the lithium ions moving from the negative electrode 24 to the positive electrode 22 and the oxygen supplied to the positive electrode 22 react with each other on the surface of the positive electrode 22 to generate a lithium oxide on the surface of the positive electrode 22, and when the lithium-air battery is charged, the lithium oxide is decomposed to generate electrical energy.

[0076] The remaining electrolyte collected at the bottom of the stacked cell container 10 is collected in the electrolyte tank 50 along the recirculation line 56 by driving the recirculation pump 58 to be reused.

[0077] When it is necessary to refill the electrolyte in the electrolyte tank 50, the electrolyte is refilled via the electrolyte refill line 60 connected to the recirculation line 56, and thus the electrolyte in the electrolyte tank 50 can be refilled.

[0078] As can be seen from the above description, a lithium-air battery according to the present invention has effects as shown below. (1) The volatilization and consumption of an electrolyte during the charging and discharging process of the lithium-air battery can be minimized, and the electrolyte can be evenly supplied to the electrodes. (2) A partial pressure of oxygen used as an active material is increased to be effectively supplied to a positive electrode during the charging and discharging process of the lithium-air battery, and a uniform oxygen supply per unit area of the positive electrode can be achieved. (3) By surrounding the end of an electrode, that is, the periphery of a negative electrode formed of lithium, with a supplementary separator extending from a separator, the electrolyte can remain on the surface of the supplementary separator and then naturally sag to the next lower unit cell, thus further facilitating the dispersed supply of the electrolyte throughout the unit cells. (4) The supplementary separator prevents the lithium negative electrode from coming into direct contact with oxygen and can thus prevent the oxidation of the lithium negative electrode. (5) A nozzle for uniformly spraying the electrolyte is installed at the top of a stacked cell container, which is capable of uniformly supplying the electrolyte to the positive electrode of the top unit cell. (6) After the reaction, the electrolyte can be returned to the electrolyte tank for reuse.

Claims

[1] A lithium-air battery comprising a plurality of unit cells (20) of different diameters, each unit cell (20) comprising: Electrodes (26), comprising: a disc-shaped positive electrode (22) having a first air flow path (22-1) passing through the positive electrode (22) in the vertical direction of the lithium-air battery, and one or more electrolyte flow paths (22-2) on the positive electrode (22) in the horizontal or vertical direction of the lithium-air battery; and a negative electrode (24) having a second air flow path (24-1) passing through the negative electrode (24) in the vertical direction and coinciding with the first air flow path (22-1), and a separator (28) arranged between the positive electrode (22) and the negative electrode (24), wherein the unit cells (20) are stacked in the vertical direction within a stacked cell container (10) such that a diffusion layer (30) is arranged between the respective unit cells (20), and a lowest unit cell (20) has the largest diameter and the diameters of the remaining unit cells (20) stacked one after the other on the lowest unit cell (20) gradually decrease vertically upwards, so that the unit cells (20) have a stepped structure. [2] The lithium-air battery according to claim 1, wherein a supplementary separator (28-1) surrounding and protecting a periphery of the negative electrode (24) extends from an outer diameter part of the separator (28). [3] The lithium-air battery according to claim 1, wherein the first air flow path (22-1) passes through a center of the positive electrode (22) in a vertical direction and has a plurality of electrolyte flow paths (22-2) on a surface of the positive electrode (22) as grooves extending in a horizontal direction from the first air flow path (22-1) to an edge of the positive electrode (22) and arranged radially. [4] The lithium-air battery according to claim 1, wherein the positive electrode (22) has an umbrella shape with the first air flow path (22-1) passing through a center of the positive electrode (22) in a vertical direction, and an electrolyte flow path (22-2) as a part of the positive electrode (22) which is inclined downward from the first air flow path (22-1) to an edge of the positive electrode (22) at a reference angle. [5] The lithium-air battery according to claim 1, wherein the first air flow path (22-1) passes through a center of the positive electrode (22) in the vertical direction, and a plurality of electrolyte flow paths (22-2) pass through the positive electrode (22) in the vertical direction through the entire positive electrode (22) from the first air flow path (22-1) to an edge of the positive electrode (22). [6] The lithium-air battery according to claim 1, wherein the positive electrode (22) comprises a plurality of concentric disks having different diameters and has the first air flow path (22-1) formed by a center of a concentric disk arranged at a central portion of the positive electrode (22) in the vertical direction, and is provided with a plurality of electrolyte flow paths (22-2) as separation spaces between the respective concentric disks in the vertical direction. [7] The lithium-air battery according to claim 1, wherein the second air flow path (24-1) passes through a center of the negative electrode (24) in the vertical direction. [8] The lithium-air battery according to claim 1, wherein an oxygen supply line (42) connected to a separate oxygen storage container (40) and an electrolyte supply line (52) connected to a separate electrolyte tank (50) are connected to an inlet of the stacked cell container (10). [9] A lithium-air battery according to claim 8, wherein a nozzle (54) connected to one end of the electrolyte supply line (52) for spraying the electrolyte evenly over the entire surface of an electrode (26) is arranged on the stacked cell container (10). [10] The lithium-air battery according to claim 1, wherein an oxygen supply line (42) connected to an oxygen storage tank (40) is connected to an inlet of the stacked cell container (10), and an electrolyte tank (50) is arranged in an upper region of an interior space of the stacked cell container (10). [11] A lithium-air battery according to claim 10, wherein nozzles (54) for uniformly spraying the electrolyte over the entire surface of an electrode (26) are attached to outlets of the electrolyte tank (50) which are arranged in the upper region of the interior of the stacked cell container (10). [12] The lithium-air battery according to claim 1, wherein a recirculation line (56) for recirculating the electrolyte is connected between a lower portion of an interior space of the stacked cell container (10) and an electrolyte tank (50), and a recirculation pump (58) is arranged on the recirculation line (56). [13] A lithium-air battery according to claim 12, wherein an electrolyte refill line (60) is connected to the recirculation line (56). [14] A lithium-air battery according to claim 1, wherein vent valves (62) for exhausting oxygen are arranged at the upper and lower parts of the stacked cell container (10). [15] A lithium-air battery according to claim 1, wherein the stacked cell container (10) has a shape of a hollow cylinder with hemispherical end portions.

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