Aluminum air battery system, and aluminum hydroxide treatment method for aluminum air battery system

Abstract

An aluminum-air (Al-Air) battery system according to one embodiment of the present invention may comprise: an aluminum-air battery unit for generating aluminum hydroxide (Al(OH)3); a filter unit for separating the aluminum hydroxide from the battery unit; a pyrolysis unit for heating the aluminum hydroxide separated by the filter unit and converting same into water vapor and aluminum oxide (Al2O3); and a cooling unit for cooling the water vapor generated by the pyrolysis unit.

Description

Aluminum air battery system and aluminum hydroxide treatment method for aluminum air battery system

[0001] The present disclosure relates to an aluminum-air battery system and a method for treating aluminum hydroxide for an aluminum-air battery system.

[0002] A secondary battery refers to a rechargeable battery capable of being charged and discharged multiple times. These secondary batteries are primarily used in various applications, such as electronic products (smartphones, laptops, tablets, etc.), electric vehicles, solar power generation, and emergency power supplies. In particular, lithium-ion batteries are used in a wide range of electronic products and electric vehicles due to their high energy density and high charge-discharge efficiency.

[0003] An aluminum-air battery is a primary battery that generates electricity using aluminum (Al) as the negative electrode and oxygen (O₂) from the air as the positive electrode. The electrochemical reaction for this is as shown in the following reaction equation 1.

[0004] <Reaction Equation 1>

[0005] 4Al + 6H2O + 3O2 → 4Al(OH)3+ Electricity generation

[0006] Aluminum-air batteries are theoretically more suitable for long-distance transportation and aircraft applications due to their higher energy density compared to lithium-ion batteries. However, aluminum-air batteries suffer from a problem where battery performance deteriorates as reaction products of aluminum (Al(OH)₃) accumulate within the electrolyte, thereby reducing the electrolyte's conductivity.

[0007] To overcome this, methods such as periodically replacing the electrolyte or disposing of the battery after use are commonly used; however, in special environments (e.g., aircraft environments), replacing or adding electrolytes is practically difficult, and the method of simply removing Al(OH)₃ has limitations as it increases water consumption, making continuous operation impossible.

[0008] The information described above disclosed in the background technology of this invention is intended only to enhance understanding of the background of the present invention and may therefore include information that does not constitute prior art.

[0009] The present disclosure provides an aluminum air battery system and a method for treating aluminum hydroxide to solve the above-mentioned problems.

[0010] However, the technical problems that the present invention aims to solve are not limited to those described above, and other unmentioned problems can be clearly understood by those skilled in the art from the description of the invention below.

[0011] An aluminum-air (Al-Air) battery system according to one embodiment of the present invention for solving technical problems may include an aluminum-air battery unit that generates aluminum hydroxide (Al(OH)3), a filter unit for separating aluminum hydroxide from the battery unit, a pyrolysis unit that heats the aluminum hydroxide separated from the filter unit to convert it into water vapor and aluminum oxide (Al2O3), and a cooling unit that cools the water vapor generated in the pyrolysis unit.

[0012] A method for treating aluminum hydroxide according to one embodiment of the present invention for solving a technical problem is a method for treating aluminum hydroxide in an aluminum-air battery system, and may include the steps of: an aluminum-air battery unit generating aluminum hydroxide; a filter unit separating aluminum hydroxide from the battery unit; a pyrolysis unit heating the aluminum hydroxide separated from the filter unit to convert it into steam and aluminum oxide; and a cooling unit cooling the steam generated in the pyrolysis unit.

[0013] According to some embodiments of the present disclosure, a system is provided for effectively separating and recovering aluminum hydroxide through pyrolysis for recycling, which can effectively reduce the amount of water involved in the overall reaction.

[0014] According to some embodiments of the present disclosure, aluminum hydroxide generated during the electrochemical reaction process of an aluminum-air battery is not simply removed but converted into aluminum oxide and water is recycled as an electrolyte, thereby enabling the more efficient operation of an aluminum-air battery system in an aircraft environment where bulk cargo weight must be reduced.

[0015] According to some embodiments of the present disclosure, the electrolyte can be continuously used while minimizing weight increase during the reaction process of the aluminum-air battery, thereby enabling long-term environmentally friendly operation in an aircraft.

[0016] However, the effects obtainable through the present invention are not limited to those described above, and other unmentioned technical effects will be clearly understood by those skilled in the art from the description of the invention below.

[0017] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention provided below; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings.

[0018] FIG. 1 is a block diagram of an aluminum air battery system according to one embodiment of the present invention.

[0019] FIG. 2 is a schematic diagram showing an aluminum air battery system according to one embodiment of the present invention.

[0020] FIG. 3 is a drawing for explaining the filter section and the surroundings of an aluminum air battery system according to one embodiment of the present invention.

[0021] FIG. 4 is a drawing for explaining the pyrolysis section of an aluminum air battery system according to one embodiment of the present invention.

[0022] FIG. 5 is a diagram illustrating the relationship between the battery section and the pyrolysis section of an aluminum air battery system according to one embodiment of the present invention.

[0023] FIG. 6 is a drawing showing a cooling section and a peripheral section thereof of an aluminum air battery system according to one embodiment of the present disclosure.

[0024] FIG. 7 is a schematic diagram showing the internal arrangement of an aircraft aluminum air battery system according to one embodiment of the present invention.

[0025] FIG. 8 is a flowchart illustrating an example of a method for treating aluminum hydroxide in an aluminum-air battery system according to one embodiment of the present invention.

[0026] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings. Instead, based on the principle that the inventor can appropriately define the concepts of terms to best describe their invention, they should be interpreted in a meaning and concept consistent with the technical spirit of the present invention. Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely some of the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention. It should be understood that various equivalents and modifications capable of replacing them may exist at the time of filing this application.

[0027] Additionally, as used herein, “comprise, include” and / or “comprising, including” specify the presence of the mentioned features, numbers, steps, actions, parts, elements, and / or groups thereof, and do not exclude the presence or addition of one or more other features, numbers, actions, parts, elements, and / or groups.

[0028] Additionally, to aid in understanding the invention, the attached drawings are not drawn to actual scale, and the dimensions of some components may be exaggerated. Furthermore, the same reference numerals may be assigned to identical components in different embodiments.

[0029] The statement that two subjects of comparison are 'identical' means that they are 'substantially identical.' Therefore, substantial identity may include deviations considered low in the industry, for example, deviations within 5%. Additionally, the statement that a parameter is uniform in a given area may mean that it is uniform from an average perspective.

[0030] Although terms such as "first," "second," etc., are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used merely to distinguish one component from another, and unless specifically stated otherwise, the first component may also be the second component.

[0031] Throughout the specification, unless specifically stated otherwise, each component may be singular or plural. Unless specifically noted otherwise in this specification, a singular representation may also include a plural. Furthermore, unless specifically noted otherwise, "A or B" may mean "including A, including B, or including A and B."

[0032] The statement that any component is positioned on the "upper (or lower) side" or the "upper (or lower) side" of a component implies not only that any component is positioned in contact with the upper (or lower) surface of said component, but also that another component may be interposed between said component and any component positioned on (or below) said component. Additionally, the area between the upper and lower parts of a component depicted in the drawings, or the remaining part excluding the upper and lower parts, may be referred to as a "side" or "lateral side." Furthermore, the direction facing the internal space of the component may be referred to as the "inner side," and the direction protruding into the open external space may be referred to as the "outer side." Such relative terms, such as "upper" and "upper side," may be used to describe the relationship between components depicted in the drawings, and the present disclosure is not limited by such terms.

[0033] Spatial relative terms such as "beneath," "below," "lower," "above," and "upper" may be used herein for ease of explanation to describe the relationship between one element or feature and another element(s) or feature(s) as illustrated in the drawings. Spatially relative positions are to be understood as encompassing different orientations of the device in use or operation, in addition to the orientations depicted in the figures. For example, if the device in the drawing is inverted, an element described as "below" or "below" is understood as "above" or "upper" of another element. Thus, the term "below" may encompass both the up and down directions.

[0034] Furthermore, where one component is described as being "on," "connected to," or "coupled to" another component, it should be understood that while the components may be directly connected or coupled to each other, another component may be "interposed" between each component, or that each component may be "connected," "coupled," or "coupled" through another component.

[0035] As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items. Additionally, the use of “may” when describing embodiments of the present disclosure relates to “one or more embodiments of the present disclosure.” Expressions such as “one or more” preceding a list of elements modify the entire list of elements and do not modify individual elements of the list.

[0036] Throughout the specification, "A and / or B" means A, B, or A and B unless specifically stated otherwise, and "C to D" means C or more and D or less, unless specifically stated otherwise.

[0037] In this specification, terms such as first, second, third, etc. may be used to describe various elements, components, regions, layers, and / or sections, but these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Accordingly, the first element, component, region, layer, or section discussed below may be named the second element, component, region, layer, or section without departing from the teachings of the exemplary embodiments.

[0038] The terms used in this specification are intended to describe embodiments of the present disclosure and are not intended to limit the present disclosure.

[0039] Unless otherwise defined in this specification, the particle size may be the average particle size. Additionally, the particle size refers to the average particle size (D50), which means the diameter of the particle whose cumulative volume in the particle size distribution is 50% by volume. The average particle size (D50) may be measured by methods widely known to those skilled in the art, for example, by measuring with a particle size analyzer, or by measuring with a transmission electron microscope (TEM) image or a scanning electron microscope (SEM) image. Alternatively, the average particle size (D50) value may be obtained by measuring using a measuring device utilizing dynamic light scattering, performing data analysis to count the number of particles for each particle size range, and then calculating from this. Alternatively, it may be measured using a laser diffraction method. When measuring by laser diffraction, more specifically, after dispersing the particles to be measured in a dispersion medium, they are introduced into a commercially available laser diffraction particle size measuring device (e.g., Microtrac MT 3000) and irradiated with ultrasound of about 28 kHz at an output of 60 W, and then the average particle size (D50) at 50% of the particle size distribution in the measuring device can be calculated.

[0040] FIG. 1 is a block diagram of an aluminum air battery system according to one embodiment of the present invention.

[0041] Referring to FIG. 1, an aluminum-air (Al-Air) battery system (100) according to one embodiment of the present invention may include an aluminum-air battery unit (110) for generating aluminum hydroxide (Al(OH)3), a filter unit (120) for separating aluminum hydroxide from the battery unit (110), a pyrolysis unit (130) for heating the aluminum hydroxide separated from the filter unit (120) to convert it into steam and aluminum oxide (Al2O3), and a cooling unit (140) for cooling the steam generated from the pyrolysis unit (130). For example, the aluminum-air (Al-Air) battery system (100) may correspond to an aluminum-air (Al-Air) battery system for aircraft.

[0042] In one embodiment, the aluminum air battery section (110) may include a battery that generates electricity using aluminum (Al) as the negative electrode and oxygen (O2) in the air as the positive electrode. To this end, the aluminum air battery system (100) may include an air inlet passage (102) capable of supplying oxygen to the aluminum air battery section (110).

[0043] For example, as illustrated in FIG. 1, the air intake passage (102) may be a channel for drawing air from the external environment of the aluminum air battery system (100). The air intake passage (102) may include an air intake for drawing air from the external environment (e.g., the external environment of an aircraft), a supply path for delivering oxygen supplied from the air intake to the battery section (110), an air purification filter for removing contaminants from the air, and an electronic valve, fan, compressor, or oxygen concentrator for controlling the amount of air intake.

[0044] In one embodiment, an electrolyte passage (112) through which a fluid electrolyte can move may be arranged between the aluminum air battery section (110) and the filter section (120). Aluminum hydroxide produced while generating power in the battery section (110) can be separated to the outside of the battery section (110) through the electrolyte passage (112). For example, the electrolyte can circulate between the battery section (110) and the filter section (120) through the electrolyte passage (112), and aluminum hydroxide can move to the filter section (120) together with the electrolyte in the form of particles dispersed in the circulating electrolyte.

[0045] In one embodiment, the filter unit (120) may perform the function of separating only aluminum hydroxide particles from the mixed solution of electrolyte and aluminum hydroxide that has moved from the battery unit (110) through the electrolyte passage (112). The filter unit (120) may separate the electrolyte and aluminum hydroxide particles through a physical method, a chemical method, or a combination of both methods.

[0046] In one embodiment, the filter unit (120) can be separated by utilizing the difference in physical properties between the electrolyte and the solid aluminum hydroxide particles. For example, since the aluminum hydroxide particles have a particle size greater than a certain size in the electrolyte, the filter unit (120) can filter the aluminum hydroxide particles using a membrane filter or a porous filter such as a mesh filter or a ceramic filter. For example, since the aluminum hydroxide particles have a higher density than the electrolyte, they can be separated by centrifugation or sedimentation.

[0047] In one embodiment, the filter unit (120) can be separated by utilizing the difference in chemical properties between the electrolyte and aluminum hydroxide. For example, the aluminum hydroxide can be recrystallized by changing its solubility through pH adjustment of the electrolyte, or the aluminum hydroxide can be precipitated into particles by adding a coagulant. For example, the coagulant may include PAC (Polyaluminum chloride) or a chelating agent.

[0048] In one embodiment, the filter section (120) may include a stirring system that maintains a smooth flow of the electrolyte and ensures that aluminum hydroxide flows evenly into the filter. Additionally, the aluminum hydroxide separated from the filter section (120) may be transported to the pyrolysis section (130) through the aluminum hydroxide passage (122). The aluminum hydroxide passage (122) may include a mechanical conveying device or a collection section, such as a pump or a spiral belt, for the uniform and smooth transport of aluminum hydroxide. The mechanical conveying device or collection section will be described later in FIG. 3.

[0049] In one embodiment, the pyrolysis unit (130) can heat aluminum hydroxide separated from the filter unit (120) to convert it into steam and aluminum oxide. The pyrolysis unit (130), which includes a heating device, can heat aluminum hydroxide to a temperature of 250 to 400 degrees Celsius to produce aluminum oxide and steam (or water) according to the following reaction equation 2.

[0050] <Reaction Equation 2>

[0051] 4Al(OH)3 → 2Al2O3 + 6H2O

[0052] The steam generated in the pyrolysis unit (130) can move to the cooling unit (140) through the steam passage (132). In one embodiment, the cooling unit (140) can cool the steam generated in the pyrolysis unit (130) and convert it back into liquid water. The liquid water is free from impurities and can be discharged to the outside of the battery system (100) or recycled internally. For example, the water converted to a liquid state or the cooled steam through the cooling unit (140) can be discharged to the outside of the battery system through the discharge passage (142) or moved to the electrolyte passage (112), etc. This will be described later in FIGS. 6 and 7.

[0053] In one embodiment, the cooling unit (140) may cool the steam heated in the pyrolysis unit (130) by utilizing an external air or cooling water circulation method. For example, the cooling unit (140) may include a condensation chamber that collects steam and converts it into water, and the condensation chamber may be in contact with a heat exchanger exposed to the external air of the aircraft. As another example, the condensation chamber may be in contact with a heat exchanger exposed to cooling water.

[0054] According to some embodiments of the present disclosure, a battery system (100) that effectively separates and recovers aluminum hydroxide through pyrolysis can be provided, thereby effectively reducing the amount of water involved in the overall reaction.

[0055] FIG. 2 is a schematic diagram showing an aluminum air battery system according to one embodiment of the present invention.

[0056] Referring to FIG. 2, an aluminum air battery system (200) according to one embodiment of the present invention may include an aluminum air battery unit (210) for generating aluminum hydroxide, a filter unit (220) for separating aluminum hydroxide from the battery unit (210), a pyrolysis unit (230) for heating the aluminum hydroxide separated from the filter unit (220) to convert it into steam and aluminum oxide, and a cooling unit (240) for cooling the steam generated in the pyrolysis unit (230). The description of each component is the same as the description given above with reference to FIG. 1.

[0057] In one embodiment, the aluminum-air battery portion (210) may include a first electrode (214), a second electrode (216), a separator (218), and an electrolyte. The first electrode (214) may be an electrode corresponding to the positive or negative electrode in the aluminum-air battery. The second electrode (216) may be an electrode corresponding to the opposite electrode to the first electrode (214). For example, if the first electrode (214) is a positive electrode, the second electrode (216) may be a negative electrode. Conversely, if the first electrode (214) is a negative electrode, the second electrode (216) may be a positive electrode.

[0058] The aluminum air battery section (210) can generate electricity by using aluminum (Al) as the negative electrode and oxygen (O2) in the air as the positive electrode. In one embodiment, when the first electrode (214) is the positive electrode, the first electrode (214) may be formed of a porous carbon electrode or a metal catalyst. The metal catalyst may be Pt, Ag, MnO 2, It may include Co3O4 or a combination thereof. If the first electrode (214) is an anode, the first electrode (214) may be in the form of a porous carbon electrode or a metal catalyst with an oxygen diffusion layer (ODL) attached or coated thereon.

[0059] In another embodiment, when the first electrode (214) is a negative electrode, the first electrode (214) may be formed of a metal such as aluminum or an aluminum alloy. For example, when the first electrode (214) is a negative electrode, the first electrode (214) may be a metal in which an additive for corrosion prevention is mixed with aluminum of 99% or higher purity. The additive for corrosion prevention may include Mg, Zn, Ga, Sn, In, Mn, Si, Ti, or a combination thereof. The second electrode (216) has a polarity opposite to that of the first electrode (214) and may have the same configuration as described above in relation to the first electrode (214).

[0060] Additionally, the aluminum air battery system (200) may include an air inlet passage (202) capable of supplying oxygen. When the first electrode (214) is a positive electrode, the air inlet passage (202) may be positioned around the first electrode (214) so ​​that a reaction with oxygen occurs quickly.

[0061] In one embodiment, the electrolyte of the aluminum-air battery section (210) may include an aqueous electrolyte. The electrolyte facilitates battery operation by mediating ion movement, and if a corrosion inhibitor is included, it may play a role in reducing unnecessary self-corrosion of aluminum. Additionally, if the electrolyte is an alkaline electrolyte, hydroxide ions (OH - Electrochemical reactions can be promoted by providing ) While electrons emitted from the cathode move to the anode, ions move within the electrolyte, allowing the electrochemical reaction to proceed smoothly. For example, the electrolyte of the aluminum-air battery part (210) may include a potassium hydroxide (KOH) solution, a sodium hydroxide (NaOH) solution, Na2SnO3, ZnO, alkyl glycoside, or a combination thereof. According to one embodiment, the aqueous electrolyte may include a strongly alkaline solution of 1 M to 6 M.

[0062] According to one embodiment, the electrolyte may circulate between the battery section (210) and the filter section (220). To this end, the battery section (210) and the filter section (220) may be connected to each other through an electrolyte passage (212). The electrolyte circulating between the battery section (210) and the filter section (220) through the electrolyte passage (212) may contain aluminum hydroxide (224) generated in the battery section (210) in the form of dispersed particles.

[0063] According to one embodiment, the filter section (220) may include a filter (226) that separates only aluminum hydroxide (224) particles from a solution mixed with an electrolyte and aluminum hydroxide (224) that has moved from the battery section (210) through an electrolyte passage (212). The filter (226) may use a general method of separating the electrolyte and solid aluminum hydroxide particles by utilizing differences in physical or chemical properties, as described above with reference to FIG. 1.

[0064] Aluminum hydroxide (224) separated in the filter section (220) can be transported to the pyrolysis section (230) through the aluminum hydroxide passage (222). According to one embodiment, the pyrolysis section (230) may include a heating device (236). The heating device (236) can heat the separated aluminum hydroxide (224) to convert it into steam (238) and aluminum oxide (234). The aluminum oxide (234) remains in the pyrolysis section (230), and the steam (238) can be moved to the cooling section (240) through the steam passage (232).

[0065] According to one embodiment, the cooling unit (240) can cool the steam generated in the pyrolysis unit (230) to convert it back into liquid water or low-temperature steam, and the liquid water or low-temperature steam can be discharged to the outside of the battery system (200) through the discharge passage (242) or recycled inside the battery system (200).

[0066] FIG. 3 is a drawing for explaining the filter section and the surroundings of an aluminum air battery system according to one embodiment of the present invention.

[0067] Referring to FIG. 3, according to one embodiment of the present invention, the filter unit (320) may include a filter (326) for separating aluminum hydroxide (324) and a stirring device (328).

[0068] The filter (326) can be configured in various forms to separate the electrolyte and solid aluminum hydroxide particles using differences in physical or chemical properties, as described above with reference to FIG. 1. For example, the filter (326) can be designed to maintain a low pressure loss (e.g., 50 mbar or less) for the smooth flow of the electrolyte.

[0069] In one embodiment, the filter (326) may be made of a material with excellent chemical resistance so that it can be maintained stably even in an alkaline electrolyte environment. For example, the filter (326) may be made of PVDF (polyvinylidene fluoride), PTFE (polytetrafluoroethylene), ceramic, or a combination thereof.

[0070] According to one embodiment of the present invention, the filter (326) may be configured to filter particles with a particle size of 0.1 μm to 10 μm.

[0071] For example, the filter (326) may have a multilayer structure. The filter (326) can filter relatively large particles (e.g., particles with a diameter of 1 μm to 10 μm) with a primary mechanical filter, and then filter relatively small particles (e.g., particles with a diameter of 0.1 μm to 1 μm) with a secondary membrane filter.

[0072] The stirring device (328) may refer to a device that optimizes the flow of the electrolyte (302) circulating between the battery section and the filter section (320) through the electrolyte passage (312). The arrow direction of the electrolyte (302) shown in FIG. 3 may indicate the flow direction of the electrolyte (302). For example, the electrolyte (302) may rotate clockwise while aluminum hydroxide (324) is filtered on the upper part of the filter (326). However, the flow direction of the electrolyte (302) is not limited thereto. The stirring device (328) may include a pump, a propeller, or a vibrating stirrer designed to maintain a constant flow rate and direction of the electrolyte (302) around the filter.

[0073] An aluminum air battery system according to one embodiment may further include a collection unit (350) that transfers aluminum hydroxide (324) separated from a filter unit (320) to a pyrolysis unit.

[0074] According to one embodiment, the collection unit (350) may include a spiral belt (356) for transporting aluminum hydroxide (324) and a dehydration device (352) for separating an electrolyte transported together with the aluminum hydroxide (324).

[0075] The collection section (350) may be an extension of the aluminum hydroxide passage (322) connected to the filter section (320). For example, the collection section (350) may include a transfer pump (not shown) that sucks in and transports aluminum hydroxide (324) filtered in the filter section (320). The transfer pump may be connected to a spiral belt (356). The spiral belt (356) can optimize the transport speed of the filtered aluminum hydroxide (324) by adjusting the belt speed and the angle of inclination. Additionally, the spiral belt (356) can prevent water vapor generated in the pyrolysis section (e.g., 230 in FIG. 2) from flowing back into the filter section (320) while controlling the height at which the filtered aluminum hydroxide (324) is supplied.

[0076] A vibration device may be added to the transfer pump or spiral belt (356) to provide vibration to prevent the aggregation of aluminum hydroxide (324) during transfer. Additionally, during the process of passing through the transfer pump or spiral belt (356), a dehydration device (352) may remove the electrolyte (302) remaining in the filtered aluminum hydroxide (324). The aluminum hydroxide (324) from which the electrolyte (302) has been removed is moved to the pyrolysis section through the aluminum hydroxide passage (358), and the separated electrolyte (302) can be recovered to the filter section (320) through the electrolyte recovery passage (354).

[0077] In one embodiment, when the weight or volume of aluminum hydroxide (324) accumulated on the filter (326) exceeds a predetermined weight or volume, or whenever a predetermined time interval passes, the filter (326) may be tilted at a predetermined angle to transfer the aluminum hydroxide (324) to the collection section (350) or the aluminum hydroxide passage (322). The filter section (320) may further include an auxiliary device (360) located below the filter (326) for transferring the aluminum hydroxide (324) to the collection section (350) or the aluminum hydroxide passage (322). The auxiliary device (360) may adjust the filter (326) to be tilted at a predetermined angle. The auxiliary device (360) may include at least one of a spiral belt, a vibration motor, and a horizontal or inclined blade. For example, if the auxiliary device (360) is a horizontal or inclined blade, the blade attached along the bottom of the filter (326) can transport the accumulated aluminum hydroxide (324) by moving at regular intervals and pushing out the aluminum hydroxide (324) particles.

[0078] FIG. 4 is a drawing for explaining the pyrolysis section of an aluminum air battery system according to one embodiment of the present invention.

[0079] Referring to FIG. 4, a pyrolysis unit (430) according to one embodiment may include a drying tank (402), a stirrer (438) placed at the bottom of the drying tank (402), and a heating device (436) placed on the side of the drying tank (402).

[0080] In one embodiment, the pyrolysis unit (430) can heat aluminum hydroxide (450) introduced through the aluminum hydroxide passage (458) to convert it into steam (408) and aluminum oxide (434). The steam (408) can move to the cooling unit through the steam passage (432).

[0081] To this end, the heating device (436) can heat aluminum hydroxide (450) to a temperature of 250 to 400 degrees Celsius. The type of heating device (436) is not limited and may include an electric heater that operates through electricity or a heater that operates by burning fuel.

[0082] In one embodiment, the stirrer (438) can control the airflow inside the drying tank (402) to prevent the aluminum oxide (434) from accumulating excessively on the surface of the drying tank (402). Alternatively, the stirrer (438) can increase the rate at which water generated by the thermal decomposition of aluminum hydroxide evaporates. The stirrer (438) may include a propeller-type stirrer, a vibrating stirrer, a magnetic field stirrer, or a combination thereof.

[0083] FIG. 5 is a diagram illustrating the relationship between the battery section and the pyrolysis section of an aluminum-air battery system according to an embodiment of the present invention. Among the configurations shown in FIG. 5, the description of the configuration corresponding to the configuration shown in FIG. 3 will be omitted.

[0084] Referring to FIG. 5, an aluminum-air battery unit (510) according to one embodiment may include a first electrode (514), a second electrode (516), a separator (518), and an electrolyte. The first electrode (514) and the second electrode (516) of the aluminum-air battery unit (510) may be connected to a Battery Management System (570) to optimize the power supply generated in the battery unit (510).

[0085] The stirrer (538) or heating device (536) of the pyrolysis unit (530) can operate using power produced in the battery unit (510) or power provided from outside the aluminum-air battery system. The external power supplied to the aluminum-air battery system can be provided from an independent external power source, which can be generated by any fuel-based power generation system. This power can be supplied through various energy conversion mechanisms, such as combustion-based generators, fuel cells, or renewable energy sources, and this may vary depending on the specific application and system configuration. The battery management system (570) can detect the status of the battery unit (510) in real time and determine the amount of power that can be supplied to the stirrer (538) or heating device (536). Additionally, the battery management system (570) can protect the aluminum-air battery system by detecting and preventing over-discharge, overcurrent, and short circuits occurring in the battery unit (510) and the pyrolysis unit (530). For example, if the power generated in the battery unit (510) drops below a certain level, the power supply to the pyrolysis unit (530) can be temporarily cut off to protect the life of the aluminum air battery.

[0086] The heating device (536) of the pyrolysis unit (530) can receive heat in various ways, which can be classified into indirect heating and direct heating methods. The direct heating method is a method of directly transferring thermal energy to the heating device, and can utilize electricity, heat transfer fluid, combustion-based systems, etc. The combustion-based heating method can utilize fossil fuels, biomass, and other combustible materials as heat sources. For example, by directly burning fossil fuels such as natural gas, coal, and petroleum and transferring the heat generated to the heating device (536), the thermal energy required for the pyrolysis process can be efficiently supplied.

[0087] Indirect heating methods may be methods in which heat is transferred through a heat transfer medium without the heat source coming into direct contact with the heating device (536). Examples include electric furnaces, heat transfer fluid circulation systems, and radiant heat heating methods. By using such methods, a uniform temperature distribution can be maintained in the pyrolysis process, and contamination by combustion by-products can be prevented. For example, an indirect heating method utilizing heat transfer fluid enables stable heat supply even at high temperatures, and depending on the type of heat source, an electric heater, a gas burner, etc., can be used.

[0088] In order to supply power to the stirrer (538) or heating device (536) of the pyrolysis unit (530), the battery management system (570) may be connected to a power conversion unit (580). The power conversion unit (580) can convert and regulate direct current (DC) power generated from the battery unit (510) so that it can be used in the heating device. For example, the power conversion unit (580) may include a DC-DC converter or a DC-AC inverter.

[0089] The pyrolysis unit (530) may further include a temperature control system that monitors the real-time temperature and power consumption of the heating device (536) through a sensor and regulates the power supply from the battery unit (510), or an energy storage and buffer unit that stores and supplies power using a supercapacitor or auxiliary battery when the battery output is momentarily unstable.

[0090] Through this, a continuous pyrolysis process can be provided by extending system lifespan and enhancing safety by minimizing energy loss and ensuring power stability.

[0091] FIG. 6 is a drawing showing a cooling section and its surroundings of an aluminum-air battery system according to one embodiment of the present disclosure. Among the configurations shown in FIG. 6, the description of the configuration corresponding to the configuration shown in FIG. 3 will be omitted.

[0092] Referring to FIG. 6, according to one embodiment, the cooling unit (640) may include a heat exchanger (648) capable of cooling water vapor using an external temperature (e.g., the external temperature of the aircraft) to increase cooling efficiency. The heat exchanger (648) may have a finned structure or a curved structure so that the heat exchange area is maximized, for example, so that cold air from outside the aircraft can effectively exchange heat with the water vapor passage (632).

[0093] High-temperature steam (638) generated during the process of the heating device (636) pyrolyzing aluminum oxide (634) in the pyrolysis unit (630) is transferred to the cooling unit (640), and the steam (638) can be converted into water (644) through the heat exchanger (648).

[0094] An aluminum air battery system (600) according to one embodiment may further include a recirculation path (642) that recirculates water vapor (638) or water (644) cooled in a cooling section (640) to a battery section (610) or a filter section (620).

[0095] According to one embodiment, the recirculation path (642) may be connected to an electrolyte passage (612) that connects the battery section (610) and the filter section (620). Through this, water (644) converted in the cooling section (640) may be added to the electrolyte circulating through the battery section (610) and the filter section (620).

[0096] According to some embodiments of the present disclosure, aluminum hydroxide (624) generated during the electrochemical reaction process of the aluminum air battery is not simply filtered through a filter (626), but is converted into aluminum oxide (634) to recycle water (644), thereby allowing the aluminum air battery system (600) to be operated more efficiently in an aircraft environment where bulk cargo weight must be reduced.

[0097] FIG. 7 is a schematic diagram showing the internal arrangement of an aluminum air battery system in an aircraft according to an embodiment of the present invention. Among the configurations shown in FIG. 7, the description of the configuration corresponding to the configuration shown in FIG. 3 will be omitted.

[0098] Referring to FIG. 7, an aluminum air battery system according to one embodiment may be arranged such that an aluminum air battery section (710), an electrolyte passage (712), a filter section (720), and a pyrolysis section (730) are located inside an aircraft (702).

[0099] In one embodiment, the cooling unit (740) may include a heat exchanger (748) capable of cooling water vapor using the external temperature of the aircraft to increase cooling efficiency. At least a portion of the heat exchanger (748) may be located outside the aircraft (702) so that cold air outside the aircraft (702) can effectively exchange heat with water vapor (738) that has moved through the water vapor passage (732).

[0100] In one embodiment, the aluminum air battery system may further include a discharge path (746) for discharging water (or water vapor) (744) cooled in the cooling section (740) to the outside of, for example, the aircraft (702).

[0101] As described above, high-temperature steam (738) generated during the process of heating aluminum hydroxide (724) by the heating device (736) in the pyrolysis unit (730) is transferred to the cooling unit (740), and the steam (738) can be converted into water (or low-temperature steam) (744) through the heat exchanger (748).

[0102] According to some embodiments of the present disclosure, aluminum hydroxide (724) generated during the electrochemical reaction process of the aluminum air battery is not simply filtered through a filter (726), but is converted into aluminum oxide (734) and discharged outside the aircraft (702) in the form of water (or low-temperature steam) (744), thereby allowing the aluminum air battery system to be operated more environmentally and efficiently in an aircraft environment where bulk cargo weight must be reduced.

[0103] FIG. 8 is a flowchart illustrating an example of a method for treating aluminum hydroxide in an aluminum-air battery system according to one embodiment of the present invention.

[0104] Referring to FIG. 8, an aluminum hydroxide treatment method (800) according to one embodiment of the present invention may be disclosed in that an aluminum air battery unit generates aluminum hydroxide (S810). According to one embodiment, the battery unit includes a first electrode, a second electrode, a separator, and an electrolyte, and the electrolyte may include an aqueous electrolyte.

[0105] Afterward, the filter unit can separate aluminum hydroxide from the battery unit (S820). According to one embodiment, the separation step (S820) may include a step of stirring the aluminum hydroxide.

[0106] A method for treating aluminum hydroxide (800) according to one embodiment may further include the step of transferring aluminum hydroxide separated in a filter section from a collection section to a pyrolysis section.

[0107] After that, the pyrolysis unit can heat the aluminum hydroxide separated from the filter unit to convert it into steam and aluminum oxide (S830). According to one embodiment, the conversion step (S830) may include the step of operating a stirrer placed at the bottom of the drying tank and a heating device placed on the side of the drying tank.

[0108] Afterward, the cooling unit can cool the steam generated in the pyrolysis unit (S840). According to one embodiment, the cooling step (S840) may include the step of exposing the heat exchanger of the cooling unit to the external temperature of the aircraft.

[0109] A method for treating aluminum hydroxide (800) according to one embodiment may further include the step of recirculating water vapor or water cooled in a cooling section to a battery section or filter section through a recirculation path.

[0110] According to some embodiments of the present disclosure, the electrolyte can be continuously used while minimizing weight increase during the reaction process of the aluminum-air battery, thereby enabling long-term environmentally friendly operation in an aircraft.

[0111] Although the present invention has been described above by means of limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs. Since various substitutions, modifications, and changes are possible within the scope of the technical spirit of the present invention without departing from it, by those skilled in the art to which the present invention belongs, the present invention is not limited by the aforementioned embodiments and attached drawings.

Claims

1. Aluminum-air (Al-Air) battery section that generates aluminum hydroxide (Al(OH)3); A filter unit for separating the aluminum hydroxide from the battery unit; A pyrolysis unit that heats the aluminum hydroxide separated in the filter unit to convert it into steam and aluminum oxide (Al2O3); and An aluminum air battery system comprising a cooling unit for cooling the water vapor generated in the above pyrolysis unit.

2. In Paragraph 1, The above battery unit includes a first electrode, a second electrode, a separator, and an electrolyte, and The above electrolyte is an aluminum-air battery system comprising an aqueous electrolyte.

3. In Paragraph 2, The above electrolyte circulates between the battery section and the filter section, Aluminum air battery system.

4. In Paragraph 2, The above aqueous electrolyte comprises a strongly alkaline solution of 1M to 6M, Aluminum air battery system.

5. In Paragraph 1, A collection unit further comprising a transfer unit for transferring the aluminum hydroxide separated in the filter unit to the pyrolysis unit. Aluminum air battery system.

6. In Paragraph 5, The above collection unit includes a spiral belt for transporting the aluminum hydroxide and a dehydration device for separating the electrolyte transported together with the aluminum hydroxide. Aluminum air battery system.

7. In Paragraph 1, The above filter unit includes a filter and a stirring device for separating the aluminum hydroxide, Aluminum air battery system.

8. In Paragraph 7, The above filter is capable of filtering particles with a particle size of 0.1 μm to 10 μm, Aluminum air battery system.

9. In Paragraph 1, The above pyrolysis unit comprises a drying tank, an agitator positioned at the bottom of the drying tank, and a heating device positioned on the side of the drying tank. Aluminum air battery system.

10. In Paragraph 9, The above stirrer or the heating device operates using power produced in the battery unit or power provided from outside the aluminum-air battery system. Aluminum air battery system.

11. In Paragraph 1, The above cooling unit includes a heat exchanger capable of cooling water vapor using an external temperature to increase cooling efficiency, Aluminum air battery system.

12. In Paragraph 1, A recirculation path further comprising a recirculation path for resupplying water vapor or water cooled in the cooling unit to the battery unit or the filter unit, Aluminum air battery system.

13. In Paragraph 1, A discharge path further comprising for discharging steam or water cooled in the above-mentioned cooling unit to the outside, Aluminum air battery system.

14. A step in which the aluminum air battery part generates aluminum hydroxide; A step in which a filter unit separates the aluminum hydroxide from the battery unit; A step in which the pyrolysis unit heats the aluminum hydroxide separated from the filter unit and converts it into steam and aluminum oxide. and A cooling unit comprising the step of cooling the water vapor generated in the pyrolysis unit, Aluminum hydroxide treatment method.

15. In Paragraph 14, The above battery unit includes a first electrode, a second electrode, a separator, and an electrolyte, and The above electrolyte includes an aqueous electrolyte. Aluminum hydroxide treatment method.

16. In Paragraph 14, A method further comprising the step of transferring the aluminum hydroxide separated from the filter unit in the collection unit to the pyrolysis unit. Aluminum hydroxide treatment method.

17. In Paragraph 14, The above separating step includes the step of stirring the aluminum hydroxide, Aluminum hydroxide treatment method.

18. In Paragraph 14, The above-mentioned converting step includes the step of operating a stirrer and a heating device, Aluminum hydroxide treatment method.

19. In Paragraph 14, The above cooling step includes the step of exposing the heat exchanger of the cooling unit to an external temperature. Aluminum hydroxide treatment method.

20. In Paragraph 14, A method further comprising the step of recirculating water vapor or water cooled in the cooling unit to the battery unit or the filter unit through a recirculation path. Aluminum hydroxide treatment method.

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