KR102248668B1 - High capacity aluminum secondary battery and method for manufacturing thereof - Google Patents

Abstract

The present invention relates to a high-capacity aluminum secondary battery and a method of manufacturing the same, and more particularly, to a high-capacity aluminum secondary battery that greatly improves capacity and stability by implementing a three-dimensional composite electrode using an active material forming a layered structure, and manufacturing the same. It's about the method.

Description

High capacity aluminum secondary battery and its manufacturing method {HIGH CAPACITY ALUMINUM SECONDARY BATTERY AND METHOD FOR MANUFACTURING THEREOF}

The present invention relates to a high-capacity aluminum secondary battery and a method of manufacturing the same, and more particularly, to a high-capacity aluminum secondary battery that greatly improves capacity and stability by implementing a three-dimensional composite electrode using an active material forming a layered structure, and manufacturing the same. It's about the method.

Recently, the demand for lithium is expected to increase rapidly due to the rapid growth of the electric vehicle and energy storage system market. There are issues such as longevity, low output, and safety, so improvement is needed.

Apart from lithium-based energy storage materials that have such resource limitations, there is a continuing need to develop secondary batteries based on alternative energy storage materials having ultra-low cost, high safety, high output and long life characteristics that can be an alternative to them. Aluminum secondary batteries are the latest technology to store energy using aluminum ions. Aluminum has many resources, is inexpensive, and is eco-friendly, so it has the potential to replace existing lithium-ion batteries for a long time in the future. It's a very high skill. Aluminum is the third largest element on the planet after oxygen and silicon (about 8.23%), and it does not have the problem of resource depletion such as lithium (0.006%), and is evenly distributed around the world, and is currently the raw material of aluminum, bauxite. The price of lithium carbonate is 1/300 of that of lithium carbonate, and the price of finished aluminum products is 1/10 of that of lithium. If lithium is replaced, raw material prices can be drastically reduced. In addition, due to the low flammability and three-electron redox reaction characteristics of aluminum, aluminum-based secondary batteries can provide low cost, high-speed charging and discharging, high capacity, and high safety, and thus are attracting great interest as a next-generation energy storage device. However, research on aluminum secondary batteries over the past several years has not been as successful as other types of secondary batteries due to problems such as low voltage, low capacity compared to lithium secondary batteries, rapid battery capacity reduction and short lifespan. Recently, the possibility of improvement of the positive electrode material, which was considered a difficult problem for aluminum secondary batteries, has been recently reported and attracting great interest in related fields.In the case of an aluminum ion battery recently reported by Professor H. Dai's research team at Stanford University, it is about 40 Wh Kg ^-1 And a high power density of up to about 3,000 W Kg ^-1. This is an energy density value comparable to that of a conventional lead acid battery and a nickel hydride battery, and a value similar to that of a supercapacitor in terms of power density (Reference: Nature 520, 324-328 (2015), Patent Publication 10-2016-0145557). .

Aluminum-based energy storage devices with low price, safety, long life, and high rate characteristics are a technology that has recently confirmed the possibility of becoming a battery. Since the original technology is the least secured, each element technology of aluminum-based energy storage devices (anode, cathode, electrolyte) It is expected that the development and improvement of the next-generation energy storage device of ultra-low cost, high capacity, high output, and high safety beyond the overall performance of lithium-ion batteries will be possible in the long term.

Republic of Korea Patent Publication No. 10-2016-0145557

The present invention provides a high-capacity aluminum secondary battery and a method of manufacturing the same, in which capacity and stability are greatly improved by implementing a composite electrode having a three-dimensional structure using an active material forming a layered structure.

The present invention includes a negative electrode part including a negative electrode current collector and a negative electrode; A positive electrode part including a positive electrode current collector and a positive electrode; A separator interposed between the anode part and the cathode part; And an aluminum secondary battery including an electrolyte, wherein the negative electrode is composed of aluminum, the positive electrode is composed of an active material constituting a layered structure, and the active material constituting the layered structure is a graphite material, a material having a one-dimensional carbon structure, or It provides an aluminum secondary battery, characterized in that composed of a composite with carbon nanoparticles.

The graphite material may include one or more selected from the group consisting of graphite film, graphite flake, and graphene.

The material of the one-dimensional carbon structure may be a carbon nanotube.

The carbon nanotubes may be single-walled carbon nanotubes or multi-walled carbon nanotubes.

The active material constituting the layered structure may be a composite of graphene and carbon nanotubes.

The anode may be formed in a three-dimensional structure in which carbon nanotubes having a one-dimensional structure are inserted between the two-dimensional graphene nanosheets.

The electrolyte may be a mixture of aluminum halide and an ionic liquid.

The aluminum halide and the ionic liquid may be mixed in a molar ratio ranging from 1.1 to 2.0:1.

The aluminum halide may include at least one selected from the group consisting _{of AlCl 3} , AlBr ₃ and AlI _3.

The ionic liquid is 1-ethyl-3-methylimidazolium chloride (1-Ethyl-3-methylimidazolium chloride, [EMIM]Cl), 1-ethyl-3-methylimidazolium bromide (1-Ethyl-3- methylimidazolium bromide, [EMIM]Br), 1-ethyl-3-methylimidazolium iodide ([EMIM]I), 1-butyl-3-methylimidazolium chloride ( 1-butyl-3-methylimidazolium cholride, [BMIM]Cl]), 1-butyl-3-methylimidazolium bromide ([BMIM]Br]), 1-butyl-3- Methylimidazolium iodide (1-butyl-3-methylimidazolium iodide, [BMIM]I]), 1-(1-butyl)pyridinium chloride) and 1-(1 -Butyl) pyridinium bromide (1- (1-butyl) pyridinium chloride) may contain one or more selected from the group consisting of.

In addition, the present invention, a negative electrode portion including a negative electrode current collector and a negative electrode; A positive electrode part including a positive electrode current collector and a positive electrode; A separator interposed between the anode part and the cathode part; And an aluminum secondary battery including an electrolyte, wherein the negative electrode is composed of aluminum, the positive electrode is composed of an active material constituting a layered structure, and the active material constituting the layered structure is composed of a transition metal dichalcogenide. It provides an aluminum secondary battery, characterized in that.

The active material constituting the layered structure may be composed of a composite of a transition metal dichalcogenide and a one-dimensional carbon structure material or carbon nanoparticles.

The transition metal dichalcogenide may be composed of MX ₂ (wherein M refers to a transition metal such as Mo, W or Ti, and X refers to a chalcogen atom such as S, Se or Te).

More specifically, it may include at least one selected from the group consisting _{of MoS 2} , WS ₂ , TiS ₂ , MoSe ₂ , WSe ₂ , TiSe _2, MoTe _2, WTe _2, and TiTe _2.

In addition, the present invention is a method of manufacturing an aluminum secondary battery comprising the step of sequentially stacking a negative electrode current collector, a negative electrode, a separator, a positive electrode, and a positive electrode current collector, and then injecting an electrolyte, wherein the negative electrode includes aluminum. Wherein the positive electrode is formed by coating a slurry prepared by mixing a graphite material or transition metal dichalcogenide, a one-dimensional carbon structure material or carbon nanoparticles, and a binder on the positive electrode current collector. It provides a method of manufacturing an aluminum secondary battery.

The binder includes at least one selected from the group consisting of polytetrafluoroethylene (PTFE), styrene-butadiene rubber (SBR), and carboxymethyl cellulose sodium salt (CMC). It can be composed, preferably styrene-butadiene rubber (styrene-butadiene rubber, SBR) and carboxymethyl cellulose sodium salt (carboxymethyl cellulose sodium salt, CMC) 1: 1 to 50 mass ratio (more preferably 1 :1 mass ratio) can be mixed and used.

The aluminum negative electrode may be laminated on the negative electrode current collector after undergoing a pretreatment process of immersing in an electrolyte solution in which aluminum halide and an ionic liquid are mixed for 1 second to 48 hours.

The aluminum halide and the ionic liquid may be mixed in a molar ratio ranging from 1.1 to 2.0:1. A detailed description of the aluminum halide and the ionic liquid is as described above.

The positive electrode is a one-dimensional carbon nanotube (or carbon nanotube) between an active material having a two-dimensional structure layered structure by using a mixture of an active material having a layered structure, carbon nanotubes (or carbon nanoparticles or carbon nanofibers), and a binder. Particles or carbon nanofibers) can be formed into a three-dimensional structure in the state of being inserted. The active material having the layered structure may be composed of a graphite material (such as graphene nanosheets) or a transition metal dichalcogenide.

In addition, the present invention is a one-dimensional structure of carbon nanotubes (or carbon nanotubes) between the active material having a layered structure of a two-dimensional structure by mixing an active material having a layered structure, carbon nanotubes (or carbon nanoparticles or carbon nanofibers) and a binder. It provides a method of manufacturing a positive electrode for an aluminum secondary battery, characterized in that formed into a three-dimensional structure in a state in which nanoparticles or carbon nanofibers) are inserted. The active material having the layered structure may be composed of a graphite material or a transition metal dichalcogenide.

In addition, the present invention, a negative electrode portion including a negative electrode current collector and a negative electrode; A positive electrode part including a positive electrode current collector and a positive electrode; A separator interposed between the anode part and the cathode part; And an energy storage device including an electrolyte, wherein the negative electrode comprises aluminum, and the positive electrode has a three-dimensional structure in which carbon nanotubes of a one-dimensional structure are inserted between active materials having a layered structure of a two-dimensional structure. It provides an energy storage device, characterized in that formed of. The active material having the layered structure may be composed of a graphite material or a transition metal dichalcogenide.

According to the present invention, it is possible to provide a high-capacity aluminum secondary battery with significantly improved capacity and stability by implementing a composite electrode having a three-dimensional structure using an active material forming a layered structure.

1 is a schematic diagram of an aluminum secondary battery.
Figure 2 shows (Figure 2a) pyrolytic graphite foil, (Figure 2b) graphene nanosheet/binder, (Figure 2c) graphene/carbon nanotube/binder (8:1:1 mass ratio, Example 1) composite electrode, ( Figure 2d) Molybdenum disulfide nanosheet electrode (Example 2, low magnification), (Figure 2e) Molybdenum disulfide nanosheet electrode (Example 2, high magnification), (Figure 2f) Molybdenum disulfide nanosheet/carbon nanotube/binder (7: 2:1 mass ratio, Example 3) A cross-sectional scanning electron microscope photograph of a composite electrode.
3 is a cyclic voltammetry curve measured using a PG foil (pyrolytic graphite foil) as a positive electrode and an electrolyte of AlCl ₃ :[EMIM]Cl (1.5:1 molar ratio) (scanning speed: 10 mV s ^-1 ) to be. Aluminum foil was used as the cathode.
FIG. 4 is a graphene/CNT composite electrode coated on a PG foil (graphene:MWCNT:CMC-SBR = 8:1:1), using an AlCl ₃ :[EMIM]Cl (1.5:1 molar ratio) electrolyte. It is a cyclic voltage-current curve (scanning speed: 10 mV s ^-1 ) measured using. Aluminum foil was used as the cathode.
Figure 5 is a constant current charging and discharging measured at a current density of ^{about 64 mA g -1} _{(± 0.561 mA) in an electrolyte of AlCl 3} :[EMIM]Cl (1.5:1 molar ratio) using a PG foil as a positive electrode. It is a curve. Aluminum foil was used as the negative electrode.
6 shows a PG foil using a positive electrode ^{, about 64 mA g -1} (± 0.561 mA), about 128 mA g ^-1 (± 1.122 mA _{) in an electrolyte of AlCl 3} :[EMIM]Cl (1.5:1 molar ratio) ), constant current charge and discharge curves measured at a current density of about 320 mA g ^{-1 (± 2.805 mA).} Aluminum foil was used as the negative electrode.
7 is a graphene:MWCNT:SBR/CMC binder = (8:1:1) in an electrolyte of AlCl ₃ :[EMIM]Cl (1.5:1 molar ratio) using a positive electrode prepared by coating a carbon composite on a PG foil. Is a constant current charge and discharge curve measured at a current density of about 60 mA g ^{-1 (± 0.561 mA).} Aluminum foil was used as the negative electrode.
8 is a graphene:MWCNT:SBR/CMC binder = (8:1:1) in an electrolyte of AlCl ₃ :[EMIM]Cl (1.5:1 molar ratio) using a positive electrode prepared by coating a carbon composite on a PG foil. Is a constant current charge and discharge curve measured at a current density of about 120 mA g ^{-1 (± 1.122 mA).} Aluminum foil was used as the negative electrode.
9 is a constant current charging measured at a current density of ^{about 53 mA g -1} _{(± 0.561 mA) in an electrolyte of AlCl 3} :[EMIM]Cl (1.5:1 molar ratio) using a molybdenum disulfide nanosheet anode, and It is a discharge curve. Aluminum foil was used as the negative electrode.

Hereinafter, the present invention will be described in more detail through examples. Objects, features, and advantages of the present invention will be easily understood through the following examples. The present invention is not limited to the embodiments described herein, and may be embodied in other forms. The embodiments introduced herein are provided to sufficiently convey the spirit of the present invention to those of ordinary skill in the art to which the present invention pertains. Therefore, the present invention should not be limited by the following examples.

The aluminum secondary battery according to an embodiment of the present invention enables reversible dissolution and deposition of aluminum in a cathode including aluminum, a cathode including an active material forming a layered structure, and at the anode. It contains an electrolyte that allows an anion intercalation and deintercalation reaction to occur. The cathode active material forming a layered structure is one-dimensional material such as graphite film, graphite flake, graphene nanosheet, graphite or graphene, and single wall or multi-wall CNT (single wall CNT). It is a carbon structure material or a composite with carbon nanoparticles.

As the electrolyte, a mixture of aluminum halide and ionic liquid is used, and the molar ratio of aluminum halide to ionic liquid is preferably from 1.1 or more to 2.0 or less. Here, the aluminum halide is AlCl ₃ and the ionic liquid is 1-ethyl-3-methylimidazolium chloride ([EMIM]Cl).

The operating mechanism of the aluminum secondary battery that occurs during the charging process is as follows (Reference: Chem. Mater. 29, 4484 (2017)), at the cathode side, during the charging and discharging reactions, metals Al, AlCl ₄ ^- and Al ₂ Cl, respectively ₇ ^- acts as an active species. _{On the anode side, mainly AlCl 4} ⁻ is intercalated and deintercalated, respectively, into the space between the graphite layer planes during the charging and discharging reactions.

7AlCl₄ ^- + Al ^{_{(Negative): 4Al 2 Cl 7 - +}} 3e -

7AlCl ₄ ^- + Al

Cx(AlCl₄ ^-) + e^- (Positive): xC + AlCl ₄ ^-

^{_{Cx (AlCl 4 -) + e}} -

The cathode active material forming the layered structure is a transition metal _{dichalcogenide (MoS 2} , WS ₂ , MoSe ₂ , WSe ₂ or MoTe _2, etc.) a nano or micro material, or a transition metal dichalcogenide and a single wall or multilayer It is a one-dimensional carbon structure material such as single wall CNT (multi wall CNT) or a composite with carbon nanoparticles. In addition, as a material for the positive electrode active material, a layered oxide having a layered structure may be used, and a composite of graphite and these materials may also be used.

The method of manufacturing an aluminum secondary battery includes (1) providing a negative electrode containing aluminum, (2) a positive electrode containing an active material capable of intercalating ions during charging and deintercalating the ions during discharge. As the step of providing, as the active material, providing a composite of at least one material selected from a layered carbon material, a layered chalcogenide material, and a layered oxide material and a carbon nanomaterial (nanoparticles, nanotubes, nanowires, etc.) ; And (3) an electrolyte that enables reversible dissolution and deposition of aluminum at the negative electrode and causes intercalation and deintercalation reactions of electrolyte ions at the positive electrode.

In an embodiment of the present invention, in the step of providing an anode, intercalation of electrolyte ions and intercalation of electrolyte ions through formation of a graphite material and carbon nanotubes, a transition metal dichalcogenide material and a carbon nanotube, or a nano-sized carbon composite In addition to facilitating deintercalation, capacity increase was possible through volume expansion, structure collapse, and electrical short-circuit improvement of the positive electrode occurring during intercalation and deintercalation.

In addition, in the step of providing the negative electrode, the oxide film on the surface of the negative electrode containing aluminum is removed through a pretreatment process in which the negative electrode containing aluminum is immersed in an electrolyte solution in which aluminum halide and an ionic liquid are mixed for 1 minute or more or 48 hours or less. The cathode activation process was included.

Example 1: Preparation of an aluminum secondary battery using a graphene/carbon nanotube composite as a positive electrode

In order to manufacture a high-capacity and high-safety positive electrode for an aluminum secondary battery, a graphene/carbon nanotube composite was formed by adding and mixing carbon nanotube powder and a binder in graphene nanosheets (concentration: 15 mg/mL) dispersed in distilled water. . Here, carbon nanotubes not only act as a conductive material, but also contribute to the formation of a three-dimensional structure that facilitates the reaction of intercalation/deintercalation of electrolyte ions to the graphene electrode, and intercalation/deintercalation. In the process, it is possible to prevent electrode collapse due to volume expansion of the graphene electrode. The electrode was prepared by mixing graphene (active material), carbon nanotubes, and a binder in an 8:1:1 mass ratio. First, the graphene nanosheets (concentration: 15 mg/L) dispersed in water and carbon nanotube powder are well mixed, and the binder is styrene-butadiene rubber (SBR) and carboxymethyl cellulose sodium salt (carboxymethyl cellulose). sodium salt, CMC) was added in a 1:1 mass ratio, dissolved, and sufficiently mixed to prepare a slurry. The slurry was evenly coated on a pyrolytic graphite foil (PG foil), which is a positive electrode current collector, and then sufficiently dried in a vacuum oven at 120° C. for 10 hours. The dried electrode was pressed using a roll-press to have a constant thickness. The pressed electrode was made of a coin type electrode with a diameter of 18 mm. As the separator, a 18mm-sized glass fiber separator (Whatman glass microfiber filters, Grade GF/B) was used, and the electrolyte was AlCl ₃ :[EMIM]Cl (1.5:1 molar ratio) ionic liquid electrolyte. An aluminum foil (10 to 300 μm thick) was used as the negative electrode, and the aluminum foil served as a current collector and a negative electrode. The aluminum cathode electrode was made of a coin-type electrode having a diameter of 18 mm (see FIG. 1). The graphene/carbon nanotube composite electrode forms a three-dimensional structure in which a one-dimensional structure of carbon nanotubes are sandwiched between two-dimensional graphene nanosheets. ion is intercalated illustration facilitates the reaction of illustration di intercalation ^- AlCl ₄ into the space between the planes. In addition, when only the existing natural graphite (van der Waals bond) is used as an anode, the electrode structure may collapse due to severe volume expansion during the charging and discharging process or electrical short circuits may occur. Since the graphene nanosheets are tightly wrapped around each other, they play a role in preventing collapse of the electrode structure and electrical short circuit due to volume expansion.

Example 2: Preparation of an aluminum secondary battery using a transition metal dichalcogenide material as a positive electrode (molybdenum disulfide, Molybdenum disulfide, MoS ₂ Anode material)

In order to manufacture a high-capacity and high-safety positive electrode for an aluminum secondary battery, molybdenum disulfide (MoS ₂ ) powder and a binder were added and mixed. The electrode was prepared by mixing molybdenum disulfide (active material) and a binder in a ratio of 9:1 by mass. _{Molybdenum disulfide (MoS 2} ) powder, which is an active material, is mixed with styrene-butadiene rubber (SBR) and carboxymethyl cellulose sodium salt (CMC) in a 1:1 mass ratio. Put together and sufficiently mixed to prepare a slurry. The slurry was evenly coated on a pyrolytic graphite foil (PG foil) or a molybdenum foil (Mo foil), which is a positive electrode current collector, and then sufficiently dried in a vacuum oven at 120° C. for 10 hours. The dried electrode was pressed using a roll-press to have a constant thickness. The compressed electrode was manufactured as a coin type electrode having a diameter of 18 mm. As the separator, a 18mm-sized glass fiber separator (Whatman glass microfiber filters, Grade GF/B) was used, and the electrolyte was AlCl ₃ :[EMIM]Cl (1.5:1 molar ratio) ionic liquid electrolyte. . An aluminum foil (10 to 300 μm thick) was used as the negative electrode, and the aluminum foil served as a current collector and a negative electrode. The aluminum cathode electrode was made of a coin-type electrode having a diameter of 18 mm (see FIG. 1). Since the molybdenum disulfide electrode forms a two-dimensional nanosheet state, similar to the graphite electrode, electrolyte ions are intercalated and deintercalated into the space between the planes of the molybdenum disulfide layer.

Example 3: Preparation of an aluminum secondary battery using a transition metal dichalcogenide-based composite material as a positive electrode (Molybdenum disulfide (MoS2) / positive electrode material using a CNT composite)

In order to manufacture a high-capacity and high-safety positive electrode for an aluminum secondary battery, molybdenum disulfide (MoS ₂ ) powder, carbon nanotube powder, and a binder were added and mixed to form a molybdenum disulfide/carbon nanotube composite. Here, carbon nanotubes not only act as a conductive material, but also contribute to the formation of a three-dimensional structure that facilitates the reaction of intercalation/deintercalation of electrolyte ions to the graphene electrode, and intercalation/deintercalation. In the process, it is possible to prevent electrode collapse due to volume expansion of the graphene electrode. The electrode was prepared by mixing molybdenum disulfide nanosheets (active material), carbon nanotubes, and a binder in a mass ratio of 7:2:1. First, mix the molybdenum disulfide nanosheet powder and the carbon nanotube powder well, and mix styrene-butadiene rubber (SBR) as a binder and carboxymethyl cellulose sodium salt (CMC) by 1:1 mass. Put together in a ratio and sufficiently mixed to prepare a slurry. The slurry was evenly coated on a pyrolytic graphite foil (PG foil) or a molybdenum foil (Mo foil), which is a positive electrode current collector, and then sufficiently dried in a vacuum oven at 120° C. for 10 hours. The dried electrode was pressed using a roll-press to have a constant thickness. The pressed electrode was made of a coin type electrode with a diameter of 18 mm. As the separator, a 18mm-sized glass fiber separator (Whatman glass microfiber filters, Grade GF/B) was used, and the electrolyte was AlCl ₃ :[EMIM]Cl (1.5:1 molar ratio) ionic liquid electrolyte. An aluminum foil (10 to 300 μm thick) was used as the negative electrode, and the aluminum foil served as a current collector and a negative electrode. The aluminum cathode electrode was made of a coin-type electrode having a diameter of 18 mm (see FIG. 1). The molybdenum disulfide nanosheet/carbon nanotube composite electrode forms a three-dimensional structure in which carbon nanotubes having a one-dimensional structure are inserted between two-dimensional molybdenum disulfide nanosheets. In addition, when only the existing molybdenum disulfide (van der Waals bond) is used as the anode, the electrode structure may collapse due to severe volume expansion during the charging and discharging process, or an electrical short may occur, but the molybdenum disulfide nanosheet/carbon nanotube composite electrode is carbon nanoparticles. Since the tube and the molybdenum disulfide nanosheets are tightly wrapped around each other, it can play a role in preventing collapse of the electrode structure and electrical short circuit due to volume expansion.

Experimental Example 1: Analysis of physical properties

In order to analyze the shape of the graphene/carbon nanotube composite electrode prepared according to the example, a cross-section of the electrode was observed using a cross-section field emission scanning electron microscopy (FESEM) equipment. 2A and 2B show cross-sectional SEM photographs of the pyrolytic graphite foil and graphene nanosheet electrode used in the present invention. FIG. 2C shows a cross-sectional SEM photograph of a graphene/carbon nanotube composite electrode, and shows that a structure in which carbon nanotubes are well mixed between graphene nanosheets and connected in a three-dimensional structure is in the form of a nanosheet.

2D and 2E are cross-sectional SEM photographs of a molybdenum disulfide nanosheet electrode (Example 2). 2F is a cross-sectional SEM photograph of a molybdenum disulfide nanosheet/carbon nanotube composite electrode (Example 3), showing that the carbon nanotubes are well mixed between molybdenum disulfide nanosheets and are connected in a three-dimensional structure in the form of a nanosheet. .

Experimental Example 2: Analysis of electrochemical properties

The aluminum secondary battery electrode is assembled in a glove box. Prior to electrode fabrication, the aluminum cathode undergoes a pretreatment process in which aluminum halide and ionic liquid are mixed for 1 second to 48 hours in an electrolyte solution. In this process, the battery can be driven by removing the oxide film or impurities on the surface of the aluminum anode. In order to evaluate the electrochemical properties of the prepared electrode _{, a cell was fabricated with a symmetrical two-electrode system structure using AlCl 3} :[EMIM]Cl (1.5:1 molar ratio) ionic liquid electrolyte. Approximately 300 μl of ionic liquid electrolyte was injected and the cell was sealed. The ionic liquid electrolyte used in the aluminum secondary battery of the present invention itself also serves as an anolyte, so it is possible to drive the battery in the form of supplying the electrolyte together with the anolyte of a redox flow battery. A multi-channel constant potentiometer (VSP potentiostat/galvanostat/EIS, BioLogic) equipment was used, and measurements were made using a cyclic voltammetry (CV) test. Cyclic voltammetry (CV) was performed at a scan rate of 10 mV/s in a voltage range from 0V to 2.5V.

3 shows a circulating voltage current curve in a voltage range from 0V to 2.5V of an aluminum secondary battery using an aluminum negative electrode and a pyrolytic graphite foil as a positive electrode, and FIG. 4 is a graphene/MWCNT composite coated with aluminum as a negative electrode. It shows the circulating voltage and current curve in the voltage range of 0-2.5V of an aluminum secondary battery using pyrolytic graphite foil as a positive electrode (scanning speed: 10 mV s ^-1 ).

5 shows a constant current discharge/charge curve measured at a current density of about 64 mA g ^-1 , and the constant current discharge/charge reaction was performed at a battery voltage of 0.01 V to 2.45 V. PG foil (about 8.5 mg, thickness: 17 μm, diameter: 18 mm) as a positive electrode of the battery, a glass fiber separator, and aluminum foil (about 17.8 mg, thickness: 25 μm, diameter: 18 mm) as an anode ). About 300 μl of an ionic liquid electrolyte ( _{a molar ratio of 1.1 to 2.0 AlCl 3} /[EMIM]Cl) was filled into the cell and sealed in a glove box. The aluminum secondary battery (cathode: aluminum foil, positive electrode: pyrolytic graphite foil) charged and discharged at a battery voltage of about 2.45 to about 0.01 V at a constant current density of about 64 mAg ^-1 has a specific capacity ^{of about 62 mAh g -1.} capacity) and 91% charge/discharge efficiency. In addition, FIG. 6 shows the specific capacity of the charged and discharged aluminum secondary battery at a battery voltage of 2.45 to 0.01V under various current density conditions of ^{64 mA g -1} , 128 mA g ^-1 and 320 mA g ^-1. ) Value, 56 mAh g ^-1 (charging/discharging efficiency: 95%) at a current density of 128 mA g ^-1 , 35 mAh g ^-1 (charging/discharging efficiency: 98% ^{) at a current density of 320 mA g -1} The specific capacity values of) are shown.

FIG. 7 shows a constant current discharge/charge curve measured at a current density of ^{about 60 mA g -1} (± 0.561 mA) using a three-dimensional electrode of a graphene/carbon nanotube composite as a positive electrode of an aluminum secondary battery, The constant current discharge/charge reaction was carried out at a cell voltage of 0.01 V to 2.45 V. Graphene/CNT composite coated on PG foil (graphene/CNT composite coated on PG foil) as a positive electrode of the battery (about 9.35 mg, thickness: 20 μm, diameter: 18 mm), a glass fiber separator, and aluminum as an anode It was constructed using foil (about 17.8 mg, thickness: 25 μm, diameter: 18 mm). About 300 μl of an ionic liquid electrolyte ( _{a molar ratio of 1.1 to 2.0 AlCl 3} /[EMIM]Cl) was filled into the cell and sealed in a glove box. The aluminum secondary battery (cathode: aluminum foil, positive electrode: graphene/carbon nanotube composite coated pyrolytic graphite foil) charged and discharged at a battery voltage of about 2.45 to about 0.01 V at a constant current density of about 60 mAg ^{-1 is about} It showed a specific capacity value of 75 mAh g ^-1 and a charge/discharge efficiency value of 82%. This is a value of about 20% increase in specific capacity compared to the case of using pyrolytic graphite anode under the same constant current condition (± 0.561 mA). FIG. 8 shows a constant current discharge/charge curve measured at a current density of about 120 mA g ^{-1 , and shows a specific capacity value of about 68 mAh g -1} and a charge/discharge efficiency value of 90%. This value is also an increase of about 21% compared to the specific capacity value of an aluminum battery using pyrolytic graphite anode (± 1.122 mA) under the same constant current condition (± 1.122 mA).

9 is a constant current charging and discharging measured at a current density of ^{about 53 mA g -1} _{(± 0.561 mA) in an electrolyte of AlCl 3} :[EMIM]Cl (1.5:1 molar ratio) using a molybdenum disulfide nanosheet anode. It is a curve. At this time, an aluminum foil was used as a negative electrode. The constant current discharge/charge reaction was carried out at a cell voltage of 0.01 V to 2.45 V. _{Molybdenum disulfide nanosheet (MoS 2} nanosheet) (about 10 mg, thickness: 10 μm, diameter: 18 mm) as a positive electrode of the battery, a glass fiber separator, and aluminum foil (about 5 mg, thickness: 10 μm, diameter: about 5 mg, thickness: 10 μm, diameter:) as an anode of the battery: 18 mm). About 300 μl of an ionic liquid electrolyte ( _{a molar ratio of 1.1 to 2.0 AlCl 3} /[EMIM]Cl) was filled into the cell and sealed in a glove box. An aluminum secondary battery (cathode: aluminum foil, positive electrode: molybdenum disulfide nanosheet) charged and discharged at a battery voltage of about 2.45 to about 0.01 V at a constant current density of about 53 mAg ^-1 has a specific capacity ^{of about 54 mAh g -1 (} specific capacity).

Claims (9)

A negative electrode part including a negative electrode current collector and a negative electrode;
A positive electrode part including a positive electrode current collector and a positive electrode;
A separator interposed between the anode part and the cathode part; And
As an aluminum secondary battery containing an electrolyte,
The negative electrode is composed of aluminum,
The positive electrode is composed of an active material and a binder constituting a layered structure, and is compressed using a roll-press to have a certain thickness,
The active material constituting the layered structure is a composite of graphene and carbon nanotubes, and is connected three-dimensionally in a state in which a one-dimensional carbon nanotube is inserted between a layered structure in which a two-dimensional graphene nanosheet is stacked. Structure, carbon nanotubes and graphene nanosheets are tightly wrapped around each other,
The carbon nanotubes contribute to the formation of the three-dimensional structure for a reaction in which anions composed of aluminum and halogen intercalate/deintercalate to the graphene electrode, and thus, the graphene electrode in the intercalation/deintercalation reaction. Aluminum secondary battery, characterized in that the collapse of the electrode due to the volume expansion of the.
The method of claim 1,
The electrolyte is a mixture of aluminum halide and an ionic liquid,
The aluminum secondary battery, characterized in that the molar ratio of the aluminum halide and the ionic liquid is in the range of 1.1 to 2.0: 1.
The method of claim 2,
The aluminum halide includes at least one selected from the group consisting _{of AlCl 3} , AlBr ₃ and AlI _3,
The ionic liquid is 1-ethyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium bromide, 1-ethyl-3-methylimidazolium iodide, 1-butyl-3-methyl An aluminum secondary battery comprising at least one selected from the group consisting of imidazolium chloride, 1-butyl-3-methylimidazolium bromide, and 1-butyl-3-methylimidazolium iodide.
A negative electrode part including a negative electrode current collector and a negative electrode;
A positive electrode part including a positive electrode current collector and a positive electrode;
A separator interposed between the anode part and the cathode part; And
As an aluminum secondary battery containing an electrolyte,
The negative electrode is composed of aluminum,
The positive electrode is composed of an active material and a binder constituting a layered structure, and is compressed using a roll-press to have a certain thickness,
The active material constituting the layered structure is a composite of a transition metal dichalcogenide and a one-dimensional carbon structure material, and a one-dimensional carbon nanostructure between the layered structure in which the two-dimensional transition metal dichalcogenide nanosheets are stacked. It is a three-dimensional structurally connected structure with a tube inserted, and the carbon nanotube and the transition metal dichalcogenide nanosheet are tightly wrapped around each other as a whole,
The carbon nanotubes contribute to the formation of the three-dimensional structure for a reaction in which anions made of aluminum and halogen intercalate/deintercalate the transition metal dichalcogenide electrode, thereby contributing to the intercalation/deintercalation reaction. In the aluminum secondary battery, characterized in that the collapse of the electrode due to volume expansion of the transition metal dichalcogenide electrode is prevented.
The method of claim 4,
The transition metal dichalcogenide _{is an aluminum secondary battery, characterized in that consisting of MX 2} (wherein M refers to Mo, W or Ti, and X refers to S, Se or Te).
A method for manufacturing an aluminum secondary battery comprising the step of sequentially stacking a negative electrode current collector, a negative electrode, a separator, a positive electrode, and a positive electrode current collector, and then injecting an electrolyte,
The negative electrode is composed of aluminum,
The positive electrode is formed by coating a slurry prepared by mixing a graphite material or transition metal dichalcogenide, a one-dimensional carbon structure material or carbon nanoparticles, and a binder on the positive electrode current collector,
The anode is a one-dimensional structure between the layered structure in which graphene or transition metal dichalcogenide nanosheets, carbon nanotube powder and a binder are mixed, and a two-dimensional structure of graphene or transition metal dichalcogenide nanosheets is stacked. It is a three-dimensional structurally connected structure in which the carbon nanotubes of are inserted, and the carbon nanotubes and graphene or transition metal dichalcogenide nanosheets are tightly wrapped around each other as a whole,
The carbon nanotubes contribute to the formation of the three-dimensional structure for a reaction in which anions composed of aluminum and halogen intercalate/deintercalate to a graphene electrode or a transition metal dichalcogenide electrode. Method of manufacturing an aluminum secondary battery, characterized in that the collapse of the electrode due to volume expansion of the graphene electrode or the transition metal dichalcogenide electrode in the intercalation reaction is prevented.
The method of claim 6,
The method of manufacturing an aluminum secondary battery, wherein the binder comprises at least one selected from the group consisting of polytetrafluoroethylene, styrene butadiene rubber, and carboxymethyl cellulose sodium salt.
The method of claim 6,
The aluminum negative electrode is a method of manufacturing an aluminum secondary battery, characterized in that after undergoing a pretreatment process in which the aluminum halide and the ionic liquid are mixed for 1 second to 48 hours and then laminated on the negative electrode current collector.
A negative electrode part including a negative electrode current collector and a negative electrode;
A positive electrode part including a positive electrode current collector and a positive electrode;
A separator interposed between the anode part and the cathode part; And
An energy storage device comprising an electrolyte,
The negative electrode is composed of aluminum,
The positive electrode is composed of an active material having a layered structure and a binder, and formed in a three-dimensional structurally connected structure in which carbon nanotubes of a one-dimensional structure are inserted between the active materials having a layered structure of a two-dimensional structure,
The active material having the layered structure is composed of graphene nanosheets or transition metal dichalcogenide nanosheets, and carbon nanotubes and graphene or transition metal dichalcogenide nanosheets are tightly wrapped around each other as a whole,
The carbon nanotubes contribute to the formation of the three-dimensional structure for a reaction in which anions composed of aluminum and halogen intercalate/deintercalate to a graphene electrode or a transition metal dichalcogenide electrode. Energy storage device, characterized in that the collapse of the electrode due to volume expansion of the graphene electrode or the transition metal dichalcogenide electrode in the intercalation reaction is prevented.

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