KR102389113B1 - Method of Synthesizing Carbon-Based Lithium Ion Battery Anode from Carbon Dioxide and Carbon-Based Lithium Ion Battery Anode Prepared Thereby - Google Patents

Abstract

The present invention relates to a method for manufacturing a carbon-based negative electrode applicable to a lithium-ion battery by utilizing carbon dioxide and a carbon-based negative electrode for a lithium-ion battery manufactured by the method, wherein carbon dioxide is used as a carbon precursor or auxiliary component to obtain boron, nitrogen Carbon dioxide, the cause of global warming and air pollution, can be synthesized as an electrode material for a lithium-ion battery, a next-generation energy storage device, by forming a composite of carbon and materials such as silicon and metal oxide and applying it as a negative electrode material for lithium-ion batteries It can be actively used in the lithium-ion battery, and it can maintain the high storage capacity of the lithium-ion battery for a long time, which can greatly contribute to the improvement of the performance of the lithium-ion battery.

Description

Method of Synthesizing Carbon-Based Lithium Ion Battery Anode from Carbon Dioxide and Carbon-Based Lithium Ion Battery Anode Prepared Thereby }

The present invention relates to a method for manufacturing a carbon-based negative electrode for a lithium-ion battery from carbon dioxide and a carbon-based negative electrode for a lithium-ion battery manufactured by the method, and more particularly, to a carbon-based negative electrode for a lithium-ion battery using carbon dioxide as a carbon precursor or an auxiliary component. , a method for manufacturing a carbon-based negative electrode for a lithium ion battery from carbon dioxide, which forms a composite of carbon with materials such as silicon and metal oxide, and can be applied as a negative electrode material for a lithium ion battery, and lithium ions manufactured by the method It relates to a carbon-based negative electrode for a battery.

Recently, environmental and energy-related problems are emerging as social issues, and efforts are being made to solve them in various ways. In particular, fossil fuels are a representative example that is closely related to the environment and energy in real life, and it is known that greenhouse gases emitted from the use of fossil fuels, air pollution and global warming, and depletion of coal and petroleum resources are known as problems. there is.

Carbon dioxide (CO ₂ ) accounts for the largest proportion of greenhouse gases that are the main culprits of global warming and has many negative effects on the atmospheric environment. Therefore, research on carbon capture and storage technology (Carbon Capture & Storage, CCS) and carbon capture and conversion technology (Carbon Capture & Utilization, CCU) is actively underway to reduce carbon dioxide emissions to the atmosphere. CCU rather than CCS solves problems and creates profits It is receiving a lot of attention as an alternative to catching two rabbits. In particular, many attempts are being made to use CO ₂ as a reactant and add various catalysts and reaction conditions to generate hydrocarbons or carbon-containing materials and reuse them as new resources in various industries such as fuel, synthesis gas, and polymers (Joshua A. Buss & Theodor) (Joshua A. Buss & Theodor). Agapie, Nature 529, 2016, 72-75), (Niraj K. Vishwakarma et al., Nature Comm. 8, 2017, 14676). However, examples of using carbon dioxide to manufacture electrode materials for lithium-ion batteries are relatively rare.

Fossil fuels, including coal and oil, account for more than half of the total energy resources, but as problems such as adverse effects on the environment and resource depletion are emerging, interest in sustainable and eco-friendly energy resources and storage methods to replace fossil fuels is rapidly increasing. is rising Among them, the most promising energy storage device is a lithium ion battery (LIB), which is currently commercialized in many electronic devices such as batteries and mobile phones, and its performance and application range are continuously expanding. The performance of lithium-ion battery electrode materials is determined from structural properties, including electrical conductivity and stability, and lithium-ion capacity in the electrolyte, and a lot of research is currently focused on developing materials that reinforce them. Carbon-based materials with strengths such as high electrical conductivity and environmental harmlessness are most commonly used as anode materials for lithium-ion batteries (Y. P. Wu et al., J. Power Sources 114, 2003, 228), and high A number of studies based on silicon and metal oxides with lithium ion capacity have also been conducted (Xin Su et al., Adv. Func. Mater. 4, 2014, 1300882, M.Zheng et al., Adv. Sci. 2018, 1700592). However, in the case of silicon and metal oxide, due to the stability problem due to the extreme volume change due to charge and discharge, most research is conducted toward securing structural stability by forming a composite with carbon or other materials rather than using it alone. is becoming Therefore, it can be seen that the carbon material is in a very important position in the anode material of the lithium ion battery.

As such, carbon dioxide has been treated as a target because of its harmful effects on the environment, and many efforts are being made to find ways to efficiently utilize it. And lithium-ion batteries are in the spotlight as a next-generation energy storage device that will be responsible for the future, and carbon materials are indispensable for the anode material of lithium-ion batteries. However, there is no case of securing performance using carbon dioxide in the manufacture of electrode materials for lithium-ion batteries.

Accordingly, the present inventors solved the above problems and made diligent efforts to prepare a carbon material that can be used as a negative electrode material of a lithium ion battery from carbon dioxide. As a result, materials such as boron, nitrogen, silicon and metal oxide using carbon dioxide as a carbon precursor or auxiliary component In the case of forming a complex of carbon with carbon dioxide, it has excellent electrical conductivity due to the introduction of carbon material, and at the same time, electrochemical activity and stability are improved from structural stability. It can be maintained for a long time, which can greatly contribute to the improvement of the performance of lithium-ion batteries, and it is meaningful in terms of environmental friendliness and economic feasibility by efficiently treating carbon dioxide, the cause of global warming and air pollution, and completing the present invention. became

An object of the present invention is to provide a method for manufacturing a carbon-based negative electrode for a lithium ion battery using carbon dioxide.

Another object of the present invention is to provide a carbon-based negative electrode for a lithium ion battery with improved high storage capacity and long life due to excellent electrical conductivity, electrochemical activity and stability.

In order to achieve the above object, the present invention provides a carbon cathode for a lithium ion battery from carbon dioxide comprising the step of (a) heating a gas containing carbon dioxide and a boron precursor under an atmosphere of an inert gas to prepare a boron-doped carbon material It provides a manufacturing method of

The present invention also provides a carbon cathode for a lithium ion battery from carbon dioxide comprising the step of (a) heating a gas containing carbon dioxide, a boron precursor, and a nitrogen precursor in an atmosphere of an inert gas to prepare a carbon material doped with boron and nitrogen It provides a manufacturing method of

The present invention also provides (a) a gas containing carbon dioxide and a carbon precursor, a boron precursor or a boron precursor and a nitrogen precursor and a silicon-containing material by heating in an atmosphere of an inert gas to prepare a silicon-carbon composite Lithium ion comprising A method for manufacturing a carbon anode for a battery is provided.

The present invention also comprises the steps of (a) recrystallizing or electrospinning a mixture of a carbon precursor, a nitrogen precursor or a boron precursor to form a carbon nanofiber precursor; and (b) oxidizing and carbonizing the carbon nanofiber precursor while supplying a gas containing carbon dioxide to prepare carbon nanofibers.

The present invention also comprises the steps of (a) recrystallizing or electrospinning a carbon precursor, a nitrogen precursor or a mixture of a boron precursor and a silicon-containing material to form a silicon-carbon nanofiber precursor; and (b) oxidizing and carbonizing the silicon-carbon nanofiber precursor while supplying a gas containing carbon dioxide to prepare a silicon-carbon nanofiber composite; Method for producing a carbon cathode for a lithium ion battery from carbon dioxide comprising a provides

The present invention also provides a lithium ion battery comprising the step of (a) heating a carbon precursor, a nitrogen precursor or a mixture of a boron precursor and a metal oxide precursor while supplying a gas containing carbon dioxide to form a metal oxide-porous carbon composite A method for manufacturing a carbon anode is provided.

The present invention also comprises the steps of (a) recrystallizing or electrospinning a mixture of a carbon precursor, a nitrogen precursor or a boron precursor to form a carbon nanofiber precursor; and (b) oxidizing and carbonizing the carbon nanofiber precursor while supplying a gas containing carbon dioxide to prepare carbon nanofibers.

The manufacturing method according to the present invention is an environmentally friendly and efficient process that utilizes carbon dioxide, which is considered to be a processing target, as a carbon precursor and auxiliary means to manufacture an electrode material usable for a negative electrode of a lithium ion battery. In addition, by applying the present invention to a lithium-ion battery representing the future energy industry, it adds meaning to eco-friendliness and economic feasibility.

The carbon-based material produced through the present invention can be provided as a negative electrode material for a lithium-ion battery, and furthermore, in addition to synthesizing the carbon material from carbon dioxide, it can be formed into a nanofiber structure or mixed with other materials such as silicon or metal oxide and Through various treatment processes including bonding, it has infinite potential to develop the performance, versatility, and application range of the existing carbon structure.

1 is a diagram schematically illustrating a method for preparing boron-doped porous carbon (BPC) according to Example 1 of the present invention.
2 is a photograph of a BPC sample prepared according to Example 1 of the present invention.
3 is a charge-discharge curve obtained from the half-cell measurement experiment of BPC in Example 1 of the present invention.
4 is a cycle curve obtained from the half-cell measurement experiment of BPC in Example 1 of the present invention.
5 is a diagram schematically showing a method for producing BNPC (Boron- and Nitrogen-doped porous carbon) according to Example 2 of the present invention.
6 is a photograph of a BNPC sample prepared according to Example 2 of the present invention.
7 is a charge-discharge curve obtained from the half-cell measurement experiment of BNPC in Example 2 of the present invention.
8 is a cycle curve obtained from the half-cell measurement experiment of BNPC in Example 2 of the present invention.
9 is a diagram schematically illustrating a method of manufacturing Si-BPC (Silicon-Boron-doped porous carbon) according to Example 3 of the present invention.
10 is a photograph of a Si-BPC sample prepared according to Example 3 of the present invention.
11 is a charge-discharge curve obtained from the half-cell measurement experiment of Si-BPC in Example 3 of the present invention.
12 is a cycle curve obtained from the half-cell measurement experiment of Si-BPC in Example 3 of the present invention.
13 is a diagram schematically illustrating a method for manufacturing carbon nanofibers according to Example 4 of the present invention.
14 is a photograph of a carbon nanofiber sample prepared according to Example 4 of the present invention.
15 is a charge-discharge curve obtained from the half-cell measurement experiment of carbon nanofibers in Example 4 of the present invention.
16 is a cycle curve obtained from the half-cell measurement experiment of carbon nanofibers in Example 4 of the present invention.
17 is a diagram schematically showing a method of manufacturing BPC / PAN CNF according to Example 5 of the present invention.
18 is a photograph of a BPC/PAN CNF sample prepared according to Example 5 of the present invention.
19 is a charge-discharge curve obtained from the half-cell measurement experiment of BPC / PAN CNF in Example 5 of the present invention.
20 is a cycle curve obtained from the half-cell measurement experiment of BPC / PAN CNF in Example 5 of the present invention.
21 is a diagram schematically illustrating a method of manufacturing Si/BPC/PAN CNF according to Example 6 of the present invention.
22 is a photograph of a Si/BPC/PAN CNF sample prepared according to Example 6 of the present invention.
23 is a charge-discharge curve obtained from the half-cell measurement experiment of Si/BPC/PAN CNF in Example 6 of the present invention.
24 is a charge-discharge curve obtained from the half-cell measurement experiment of Si/BPC/PAN CNF in Example 6 of the present invention.
25 is a diagram schematically showing a method of manufacturing CO/PC (Cobalt oxide/Porous carbon composite) according to Example 7 of the present invention.
26 is a photograph of a CO/PC sample prepared according to Example 7 of the present invention.
27 is a charge-discharge curve obtained from a half-cell measurement experiment of CO/PC in Example 7 of the present invention.
28 is a cycle curve obtained from a half-cell measurement experiment of CO/PC in Example 7 of the present invention.
29 is a view schematically showing a manufacturing method of MO / PC (Manganese oxide / Porous carbon composite) according to Example 8 of the present invention.
30 is a photograph of a MO/PC sample prepared according to Example 8 of the present invention.
31 is a charge/discharge curve obtained from a half-cell measurement experiment of MO/PC in Example 8 of the present invention.
32 is a cycle curve obtained from the half-cell measurement experiment of MO/PC in Example 8 of the present invention.
33 is a diagram schematically illustrating a method of manufacturing FeO/PC (Iron oxide/Porous carbon composite) according to Example 9 of the present invention.
34 is a photograph of the FeO/PC sample prepared according to Example 9 of the present invention.
35 is a charge-discharge curve obtained from a half-cell measurement experiment of FeO/PC in Example 9 of the present invention.
Figure 36 is a cycle curve obtained from the half-cell measurement experiment of FeO / PC in Example 9 of the present invention.
37 is a diagram schematically illustrating a method for manufacturing a BPC/PAN interlayer according to Example 10 of the present invention.
38 is a photograph of a BPC/PAN interlayer sample prepared according to Example 10 of the present invention.
39 is a charge-discharge curve obtained by applying the BPC / PAN intermediate layer prepared according to Example 10 of the present invention to a silicon-based anode half-cell measurement experiment.
40 is a cycle curve obtained by applying the BPC/PAN intermediate layer prepared according to Example 10 of the present invention to a silicon-based anode half-cell measurement experiment.
41 shows parts and names used for cell assembly in Examples 1 to 11 of the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In general, the nomenclature used herein is those well known and commonly used in the art.

In the present invention, carbon dioxide is converted into a carbon precursor or boron, nitrogen, silicon, and metal oxide by heating, recrystallizing, or electrospinning a mixture of a carbon precursor, a boron precursor and/or a nitrogen precursor, and a silicon-containing material or metal oxide precursor. By acting as an oxidizing agent, it can be converted into an efficient, functional and stable composite structure and can be used as an anode material for a lithium-ion battery with excellent performance. .

Accordingly, the present invention in one aspect (a) heating a gas containing carbon dioxide and a boron precursor in an atmosphere of an inert gas to prepare a carbon material doped with boron from carbon dioxide, the production of a carbon cathode for a lithium ion battery it's about how

In another aspect, the present invention provides carbon for lithium ion batteries from carbon dioxide, comprising the step of (a) heating a gas containing carbon dioxide, a boron precursor, and a nitrogen precursor in an atmosphere of an inert gas to prepare a carbon material doped with boron and nitrogen It relates to a method for manufacturing an anode.

In another aspect, the present invention includes (a) heating a gas containing carbon dioxide and a carbon precursor, a boron precursor or a boron precursor and a nitrogen precursor and a silicon-containing material under an atmosphere of an inert gas to prepare a silicon-carbon composite It relates to a method for manufacturing a carbon anode for a lithium ion battery.

In another aspect, the present invention comprises the steps of (a) recrystallizing or electrospinning a mixture of a carbon precursor, a nitrogen precursor or a boron precursor to form a carbon nanofiber precursor; and (b) oxidizing and carbonizing the carbon nanofiber precursor while supplying a gas containing carbon dioxide to produce carbon nanofibers; relates to a method of manufacturing a carbon cathode for a lithium ion battery comprising a.

In another aspect, the present invention comprises the steps of (a) recrystallizing or electrospinning a carbon precursor, a nitrogen precursor or a mixture of a boron precursor and a silicon-containing material to form a silicon-carbon nanofiber precursor; and (b) oxidizing and carbonizing the silicon-carbon nanofiber precursor while supplying a gas containing carbon dioxide to prepare a silicon-carbon nanofiber composite; Method for producing a carbon cathode for a lithium ion battery from carbon dioxide comprising a is about

In another aspect of the present invention, (a) a carbon precursor, a nitrogen precursor or a mixture of a boron precursor and a metal oxide precursor is heated while supplying a gas containing carbon dioxide as an oxidizing agent and a carbon precursor to form a metal oxide-porous carbon composite It relates to a method for manufacturing a carbon cathode for a lithium ion battery comprising a.

In another aspect, the present invention comprises the steps of (a) recrystallizing or electrospinning a mixture of a carbon precursor, a nitrogen precursor or a boron precursor to form a carbon nanofiber precursor; and (b) oxidizing and carbonizing the carbon nanofiber precursor while supplying a gas containing carbon dioxide to produce carbon nanofibers; it relates to a method for manufacturing a carbon cathode interlayer for a lithium ion battery comprising a. .

Hereinafter, the present invention will be described in detail.

A method of manufacturing a carbon anode for a lithium ion battery according to a preferred embodiment of the present invention is (a) heating a gas containing carbon dioxide, a carbon precursor, a boron precursor, or a boron precursor and a nitrogen precursor under an inert gas atmosphere to obtain boron or boron and preparing a carbon material doped with nitrogen; and (b) mixing a conductive material and/or a binder solution with the carbon material doped with boron or boron and nitrogen, and then evaporating the solvent from the resulting slurry to prepare a carbon cathode.

According to another preferred embodiment of the present invention, the method for manufacturing a carbon anode for a lithium ion battery comprises (a) a gas containing carbon dioxide, a carbon precursor, a boron precursor or a boron precursor, a nitrogen precursor, and a silicon-containing material under an inert gas atmosphere. heating to prepare a silicon-carbon composite; and (b) mixing a conductive material and/or a binder solution with the silicon-carbon composite, and then evaporating the solvent from the resulting slurry to prepare a carbon cathode.

In addition, the method of manufacturing a carbon cathode for a lithium ion battery according to another preferred embodiment of the present invention is (a) a carbon precursor, a nitrogen precursor or a mixture of a boron precursor or a carbon precursor, a nitrogen precursor or a mixture of a boron precursor and a silicon-containing material Recrystallizing or electrospinning to form a carbon nanofiber precursor or a silicon-carbon nanofiber precursor; and (b) producing carbon nanofibers by oxidizing and carbonizing the carbon nanofiber precursor or silicon-carbon nanofiber precursor while supplying a gas containing carbon dioxide. After step (b), the carbon nanofiber or silicon-carbon nanofiber composite may further comprise evaporating a solvent, preferably, the carbon nanofiber or the silicon-carbon nanofiber composite is challenged. After mixing the ash and binder solution, the solvent may be evaporated from the resulting slurry.

In addition, the method for manufacturing a carbon cathode for a lithium ion battery according to another preferred embodiment of the present invention is (a) heating a carbon precursor, a nitrogen precursor or a mixture of a boron precursor and a metal oxide precursor while supplying a gas containing carbon dioxide. forming a metal oxide-porous carbon composite; and (b) mixing a binder solution with the metal oxide-porous carbon composite, and then evaporating the solvent from the resulting slurry to prepare a carbon cathode.

In the present invention, (b) the carbon material doped with boron, the carbon material doped with boron and nitrogen, a silicon-carbon composite or a metal oxide-carbon composite is mixed with a conductive material and/or a binder solution, and then the resulting It may further comprise evaporating the solvent from the slurry.

In addition, the method for manufacturing a carbon anode intermediate layer for a lithium ion battery according to another preferred embodiment of the present invention comprises the steps of (a) recrystallizing or electrospinning a mixture of a carbon precursor, a nitrogen precursor, or a boron precursor to form a carbon nanofiber precursor ; and (b) producing carbon nanofibers by oxidizing and carbonizing the carbon nanofiber precursor while supplying a gas containing carbon dioxide.

It may further include evaporating the solvent from the carbon nanofibers after step (b), and preferably includes a method of applying the carbon nanofibers as an intermediate layer between the separator and the negative electrode of a lithium ion battery. .

The carbon precursor used in the present invention may be a material in which carbon accounts for 20% or more, preferably 50% or more of the total mass, and boron or nitrogen elements are included in the composition. Carbon dioxide (CO ₂ ) gas can be used as a carbon precursor, and amorphous carbon materials such as activated carbon, carbon black, charcoal, etc., and crystalline such as graphite and graphene A carbon material, and a polymer material such as polyacrylonitrile (PAN) and polyaniline (PANI) may also be used, but the present invention is not limited thereto.

The boron precursor used in the present invention is boron oxide (B ₂ O ₃ ), boric acid (H ₃ BO ₃ ), lithium borohydride (LiBH ₄ ), sodium borohydride (NaBH ₄ ), potassium borohydride (KBH) ₄ ), magnesium borohydride (Mg(BH ₄ ) ₂ ), calcium borohydride (Ca(BH ₄ ) ₂ ), strontium borohydride (Sr(BH ₄ ) ₂ ) and ammoniaborane (NH ₃ BH ₃ ) ) may be selected from the group consisting of at least one, preferably sodium borohydride, but is not limited thereto.

Nitrogen precursor used in the present invention is polypyrrole (polypyrrole), polyaniline (polyaniline), melamine (C ₃ H ₆ N ₆ ), PDI (N,N'-bis(2,6-diisopropyphenyl)-3,4, 9,10-perylenetetracarboxylicdiimide), polyacrylonitrile (PAN), urea (CO(NH ₂ ) ₂ ), ammonia (NH ₃ ), ammonia hydroxide (NH ₄ OH), hydrazine (N ₂ H ₄ ), ammonia Borane (NH ₃ BH ₃ ) and nitrogen gas (N ₂ ) may be selected from the group consisting of at least one, preferably polyacrylonitrile or nitrogen gas (N ₂ ), but is not limited thereto .

The silicon-containing material used in the present invention is silicon nanopowder or silicon nanoparticles of nanowires (Si nanoparticles), silicon dioxide (SiO ₂ ), silicon carbide (SiC), silicon tetrachloride (SiCl ₄ ), silicon nitride (Si ₃ N ₄ ) ), silicon acetate (Si(OCOCH ₃ ) ₄ ), silicon tetrafluoride (SiF ₄ ), silicon tetrabromide (SiBr ₄ ), silicon monoxide (SiO) and tetraethyl orthosilicate (Si(OEt) ₄ ) One or more types may be selected from the group consisting of, and preferably, silicon nanopowder or silicon nanoparticles of nanowires are used, but the present invention is not limited thereto.

As a metal oxide precursor used in the present invention, cobalt chloride (CoCl ₂ ), cobalt bromide (CoBr ₂ ), cobalt iodide (CoI ₂ ), carbonyl cobalt (Co ₂ (CO) ₈ ), cobalt acetate (Cobalt) (II) acetate), cobalt naphthenate, cobalt nitrate (Co(NO ₃ ) ₂ ), cobalt sulfate (CoSO ₄ ), and cobalt oxide precursor group consisting of cobalt acetylacetonate; Potassium permanganate (KMnO ₄ ), potassium manganate (K ₂ MnO ₄ ), barium manganate (BaMnO ₄ ), manganese chloride, manganese sulfate, manganese sulfide (MnS), manganese (II) ) acetate), manganese oxide composed of manganese(II) acetylacetonate, manganese(II) bromide, MnBr ₂ ), and manganese(II) nitrate, Mn(NO ₃ ) ₂ ). A group of precursors, and iron chloride (II, FeCl ₂ ), iron chloride (III, FeCl ₃ ), iron bromide (FeBr ₂ ) iron iodide (iron (II) iodide, FeI ₂ ), iron sulfide (FeS), iron disulfide (FeS ₂ ) and iron acetylacetonate (iron(III) acetylacetonate) may be selected from the group consisting of at least one iron oxide precursor.

The mixing method includes both physical mixing and mixing under a solvent, and the solvent at this time is dimethyl formamide (DMF), dimethyl sulfoxide (DMSO), isopropyl alcohol (isopropyl alcohol) , IPA) or mixtures thereof.

The heating, recrystallization or electrospinning step after mixing is a step for converting the mixed precursors into a more efficient and functional structure.

In the case of heating, the temperature can be raised to 400 to 700 °C at a rate of 1 to 10 °C min ^-1 .

Silicon and boron precursor complexes are also formed through recrystallization.

In the case of electrospinning, the surface area and reaction area can be increased by forming a nanofiber structure from a mixed solution. During electrospinning, the distance between the syringe needle and the collector is 10-15 cm, the radiation angle to the collector is 30-50 degrees horizontally, the operating voltage is 15-20 kV, and the radiation flow rate is 0.5-2 mL/ h is preferred, but may not be limited to this condition.

In the present invention, the oxidation and carbonization reaction is maintained at 200-1200 ℃ for 0.5-5 hr by raising the temperature at a rate of 1-10 ℃/min in an inert gas condition such as nitrogen (N ₂ ) or argon (Ar). . At 300-600 ℃, carbon dioxide (CO ₂ ) gas is sometimes introduced, and at this time, the inert gas may be introduced or the inflow may be limited. Carbon dioxide may be a precursor of a carbon material and may act as an oxidizing agent to oxidize the material. At this time, the flow rate of nitrogen or inert gas is preferably 20 to 200 ml/min, and the flow rate of carbon dioxide is preferably 50 to 200 ml/min.

의 오븐에서 6~48 hr 정도 건조하는 것이 바람직하다.In the present invention, it may further include a step of washing with acid, water or alcohol after the heating or recrystallization or electrospinning step. This step is to remove by-products or salts contained in the obtained carbon material and product, and it is preferable to treat with deionized water (DIW) between room temperature and 90 °C. In this process, an acid such as hydrochloric acid or sulfuric acid, and a step of washing with alcohol may be further included. The alcohol may be at least one selected from the group consisting of methanol, ethanol and propanol. The step of drying the carbon material washed with hot water, acid, and alcohol is 50 to 130

It is preferable to dry it in an oven for 6 to 48 hr.

In the present invention, the silicon-carbon composite, carbon nanofiber or metal oxide-porous carbon composite can be used as an electrode as it is, and is made by mixing a current collector, a conductor, a binder, etc. in a certain ratio. may be lost

As a current collector used in the negative electrode, copper foil is generally used, but rigid supports may be used.

Conductive materials include carbon nanotube (CNT), graphite, graphene, super-P, carbon black, ethylene black, acetylene black ( At least one type may be selected from the group consisting of acetylene black) and ketjen black.

As a binder, polyvinylidene fluoride (PVDF), synthetic rubber (styrene butadiene rubber, SBR), polytetrafluoroethylene (PTFE), polyvinyl alcohol (PVA), carboxymethyl cellulose (carboxymethyl cellulose, CMC) and One or more types may be selected from the group consisting of polyacrylic acid (PAA).

In the present invention, the interlayer prepared from carbon nanofibers may be applied as an intermediate layer between the separator and the negative electrode as it is (free-standing interlayer), or may be applied by attaching it to the separator or the negative electrode.

Hereinafter, preferred examples are presented to help the understanding of the present invention, but the following examples are merely illustrative of the present invention, and it will be apparent to those skilled in the art that various changes and modifications are possible within the scope and spirit of the present invention, It goes without saying that such variations and modifications fall within the scope of the appended claims.

[Example]

Example 1: carbon dioxide (CO ₂ ) production of carbon negative electrode material (BPC) of boron-doped lithium-ion battery from

Sigma Aldrich's sodium borohydride (NaBH ₄ ) was used as a boron precursor, and carbon dioxide served as a carbon precursor. The manufacturing method is shown in FIG. 1, and is described in detail as follows.

Sodium boron hydride (NaBH ₄ ) 3g was taken out, put in a crucible, and put in a furnace reactor, the temperature was raised from room temperature to 500 °C at a temperature increase rate of 5 °C/min, and then the temperature was maintained for 2 hours. When the temperature was raised, argon (Ar) gas with a flow rate of 50 ml/min was flowed, and when the furnace temperature reached 500° C., the argon gas was converted into carbon dioxide gas with a flow rate of 76 ml/min. The gas and flow rate were maintained at 500° C. for 2 hours and thereafter until the temperature was lowered to room temperature. Before raising the temperature of the furnace for the first time, argon was flowed for at least 30 min to create a sufficient argon environment in the furnace, and then the temperature was started.

After the reaction was completed, the sample was transferred to a 250 ml beaker, 200 ml of a 5 M hydrochloric acid (HCl) solution was poured, and then stirred at 80 ° C. for 1 hour at 500 rpm. Thereafter, the solution except for the sample was removed through a reduced pressure filter device. After repeating this step once more, the same process was repeated 5 times using deionized water (DIW) at 80 °C. Finally, the process was repeated one more time at room temperature using ethanol, and the sample was dried in an oven at 80° C. for more than 24 hours.

The boron-doped porous carbon (BPC) material shown in FIG. 2 made from carbon dioxide in this way was used as an electrode material of a lithium ion battery. The specific process is as follows.

오븐에서 24 시간 이상 건조시켜 NMP 용매를 증발시켰다.Put 20 mg of polyvinylidene fluoride (poly-1,1-difluoroethene, PVDF) and 1.5 ml of methylpyrrolidone (N-Methyl-2-pyrrolidone, NMP) in a 10 ml vial and stir at 500 rpm for 1 hour. A mixed solution was prepared. 60 mg of BPC and 20 mg of carbon black were mixed evenly using a pestle and mortar, and then put into the previously prepared PVDF and NMP mixed solution and stirred at 1000 rpm for 24 hours. Take out the mixture in the form of a slurry made in this way and apply it flat on a copper foil, 70

The NMP solvent was evaporated by drying in an oven for at least 24 hours.

The electrode made as above was used as a working electrode (WE), lithium metal (Li metal) was used as a counter electrode (CE) and a reference electrode (Standard electrode, SE), and an organic electrolyte of 1 M hex Coin-cell type lithium-ion battery using lithium hexafluorophosphate solution in ethyl carbonate and diethyl carbonate, 1.0 M LiPF ₆ in EC/DEC = 50/50 (v/v)) as electrolyte A half-cell experiment was performed. A detailed assembly process is shown in FIG. 41 and is as follows.

A lithium metal punched with a diameter of 10 mm was placed in the center of the case, and an appropriate pressure was applied to fix it to the case so as not to move. 5 μL of electrolyte, a separator purchased from Celgard and punched with a diameter of 14 mm, 10 μL of electrolyte, a working electrode punched with a diameter of 10 mm, a gasket, a spacer, and a spring stacked and finally covered with a cap. The assembled cell was further sealed using a sealing machine and then mounted on a measuring device to observe the performance of the electrode. All assembly processes before attaching the cell to the measuring device were carried out in a glove box in an argon environment where moisture and oxygen were blocked.

As a result of the experiment, as shown in FIGS. 3 and 4, a charge/discharge curve and a cycle curve were obtained, and from this, a voltage range of 0.01 to 3.0 V and a current density of 1 A/g, based on a current density of 500 mAh/g ( capacity) was confirmed to be maintained over 100 cycles.

Example 2: carbon dioxide (CO ₂ ) and nitrogen (N ₂ ) production of carbon negative electrode material (BNPC) of lithium-ion battery doped with boron and nitrogen simultaneously

Sigma Aldrich's sodium borohydride (NaBH ₄ ) was used as a boron precursor, and carbon dioxide and nitrogen acted as precursors of carbon and nitrogen, respectively. The manufacturing method is shown in FIG. 5, and is specifically described as follows.

Sodium boron hydride (NaBH ₄ ) 3 g was taken out, put in a crucible, and put in a furnace reactor, the temperature was raised from room temperature to 500 °C at a temperature increase rate of 5 °C/min, and then the temperature was maintained for 2 hours. When the temperature was raised, argon (Ar) gas with a flow rate of 50 ml/min was flowed, and when the furnace temperature reached 500 °C, argon gas was converted into carbon dioxide gas at a flow rate of 76 ml/min and nitrogen (N ₂ at a flow rate of 76 ml/min). ) was converted to a mixture of gases. The gas and the flow rate were maintained at 500° C. for 2 hours and thereafter until the temperature was lowered to room temperature. Before raising the temperature of the furnace for the first time, argon was flowed for at least 30 min to create a sufficient argon environment in the furnace, and then the temperature was started.

After the reaction was completed, the sample was transferred to a 250 ml beaker, 200 ml of a 5 M hydrochloric acid (HCl) solution was poured, and then stirred at 80 ° C. for 1 hour at 500 rpm. Thereafter, the solution except for the sample was removed through a reduced pressure filter device. After repeating this step once more, the same process was repeated 5 times using deionized water (DIW) at 80 °C. Finally, the process was repeated one more time at room temperature using ethanol, and the sample was dried in an oven at 80° C. for 24 hours or more.

The boron- and nitrogen-doped porous carbon (BNPC) material shown in FIG. 6 made from carbon dioxide in this way was used as an electrode material of a lithium ion battery. The specific process is as follows.

Put 20 mg of polyvinylidene fluoride (poly-1,1-difluoroethene, PVDF) and 1.5 ml of methylpyrrolidone (N-methyl-2-pyrrolidone, NMP) in a 10 ml vial, and stir at 500 rpm for 1 hour. A mixed solution was prepared. After mixing 60 mg of BNPC and 20 mg of carbon black using a pestle and mortar, it was put into the previously prepared PVDF and NMP mixed solution and stirred at 1000 rpm for 24 hours. The mixture in the form of a slurry prepared in this way was taken out, applied flatly on a copper foil, and dried in an oven at 70° C. for more than 24 hours to evaporate the NMP solvent.

A measurement experiment was performed by assembling the half-cell of the electrode made as above in the same manner as in Example 1. As a result of the experiment, from the charge/discharge curves and cycle curves shown in FIGS. 7 and 8, based on a voltage range of 0.01 to 3.0 V and a current density of 1 A/g, a capacity of 500 mAh/g was maintained for more than 60 cycles. confirmed that.

Example 3: Silicon (Si) and carbon dioxide (CO ₂ ) production of silicon-carbon composite anode material (Si-BPC) for lithium-ion batteries

Silicon nanopowder & nanowire mixed (Silicon nanopowder & nanowire mixed) product of US-NANO was used for silicon, and sodium borohydride (NaBH ₄ ) product of Sigma Aldrich was used, and carbon dioxide serves as a carbon precursor did The manufacturing method is shown in FIG. 9, and is described in detail as follows.

In a 20 ml vial, 1.5 g of NaBH ₄ and 1 ml of isopropyl alcohol (IPA) were added and sonication was performed for 2 min. In addition, 0.25 g of silicone was added thereto, sonicated for 1 hour, and dried in an oven at 70° C. for one day to evaporate IPA.

The NaBH ₄ and Si mixture made through the above process was put in a crucible and put in a furnace reactor, and the temperature was raised from room temperature to 500 °C at a temperature increase rate of 5 °C/min, and then the temperature was maintained for 2 hours. When the temperature was raised, argon (Ar) gas with a flow rate of 50 ml/min was flowed, and when the furnace temperature reached 500 ° C, argon gas was used as a mixed gas of carbon dioxide gas and nitrogen (N ₂ ) gas with each flow rate of 76 ml/min. was converted to The gas and the flow rate were maintained at 500° C. for 2 hours and thereafter until the temperature was lowered to room temperature. Before raising the temperature of the furnace for the first time, argon was flowed for at least 30 min to create a sufficient argon environment in the furnace, and then the temperature was started.

After the reaction was completed, the sample was transferred to a 250 ml beaker, 200 ml of a 5 M hydrochloric acid (HCl) solution was poured, and then stirred at 80 ° C. for 1 hour at 500 rpm. Thereafter, the solution except for the sample was removed through a reduced pressure filter device. After repeating this step once more, the same process was repeated 5 times using deionized water (DIW) at 80 °C. Finally, the process was repeated one more time at room temperature using ethanol, and the sample was dried in an oven at 80° C. for more than 24 hours.

The silicon-carbon composite obtained from the above process was put in a crucible and put into a furnace reactor, and the temperature was raised from room temperature to 950 °C at a temperature increase rate of 10 °C/min, and then the temperature was maintained for 2 hours. Argon gas of 50 ml/min flow was flowed in the whole process including temperature increase and holding time, and argon was flowed for at least 30 min before heating the furnace to make the furnace sufficiently argon environment, and then the temperature was started.

The silicon-carbon composite (Silicon-Boron-doped porous carbon, Si-BPC) shown in FIG. 10 thus made was used as an electrode material for a lithium ion battery. The specific process is as follows.

Put 20 mg of polyvinylidene fluoride (poly-1,1-difluoroethene, PVDF) and 1.5 ml of methylpyrrolidone (N-Methyl-2-pyrrolidone, NMP) in a 10 ml vial and stir at 500 rpm for 1 hour. A mixed solution was prepared. After mixing 60 mg of Si-BPC and 20 mg of carbon black using a pestle and mortar, it was put into the previously prepared PVDF and NMP mixed solution and stirred at 1000 rpm for 24 hours. The mixture in the form of a slurry thus prepared was taken out, applied flat on a copper foil, and dried in an oven at 70° C. for 24 hours or more to evaporate the NMP solvent.

A measurement experiment was performed by assembling the half-cell of the electrode made as above in the same manner as in Example 1. As a result of the charge/discharge curves and cycle curves of FIGS. 11 and 12 , an electric capacity of 210 mAh/g was shown based on a voltage range of 0.01 to 1.5 V and a current density of 500 mA/g.

Example 4: carbon dioxide (CO ₂ ) from polyacrylonitrile (PAN) using carbon nanofiber-based lithium-ion battery negative electrode material manufacturing

A method of manufacturing a porous carbon nanofiber-based negative electrode material from polyacrylonitrile (PAN) using carbon dioxide is shown in FIG. 13 and will be described in detail as follows.

PAN purchased from Sigma Aldrich was used as both a carbon precursor and a nitrogen precursor, and carbon dioxide was used as an oxidizing agent for PAN.

A solution was prepared by adding 0.7 g of PAN to 7 g of dimethyl formamide (DMF) and stirring at 150 rpm for 2 hours at room temperature. Remove the piston from the syringe with the 21 gauge needle and transfer the solution made inside with a dropper. After reinserting the piston, the air inside the syringe was removed to prevent the internal solution from leaking upward toward the needle. Electrospinning was performed by attaching a syringe containing the solution to the electrospinning test apparatus. In this case, the electrospinning conditions are as follows. The distance between the syringe needle and the collector was 13 cm, and it was set at an angle of 40 degrees horizontally from the collector. The solution was spun on the collector at a voltage of 18 kV and a flow rate of 1.5 mL/h. During the spinning process, the solvent, DMF, is evaporated and only PAN is spun in the form of nanofibers.

PAN nanofibers with a diameter of 200 nm to 300 nm produced by electrospinning are precursors of carbon nanofibers and are converted into carbon nanofibers through oxidation and carbonization processes. The process is as follows. PAN nanofibers were placed in a furnace reactor and nitrogen was flowed at a flow rate of 50 mL/min. At this time, the reaction conditions were raised from room temperature to 200 °C at a temperature increase rate of 5 °C/min, and the temperature was maintained for 3 hours. After that, the temperature was raised to 500 °C at 5 °C/min, and carbon dioxide was flowed at a flow rate of 75 ml/min to maintain the temperature for 2 hours. At this time, nitrogen is not introduced, only carbon dioxide flows, and in this process, PAN is mildly oxidized by carbon dioxide. After 2 hours, the inflow of carbon dioxide was stopped, nitrogen was flowed at a flow rate of 50 mL/min, and the temperature was again raised to 750 °C at 5 °C/min and maintained for 1 hour. In this process, mild oxidized PAN nanofibers were It is carbonized to become carbon nanofibers. After that, the prepared carbon nanofibers were cooled to room temperature and punched out in a circle shape with a diameter of 10 mm by a punching machine without mixing with a conductive material, a binder, and a current collector, and used as a negative electrode in a lithium ion battery. The carbon nanofiber electrode used as the negative electrode of the lithium ion battery can be seen in FIG. 14 .

The electrode made as above was used as a working electrode (WE), lithium metal (Li metal) was used as a counter electrode (CE) and a reference electrode (Standard electrode, SE), and an organic electrolyte of 1 M hex Half coin-cell type lithium-ion battery using lithium hexafluorophosphate solution in ethyl carbonate and diethyl carbonate, 1.0 M LiPF6 in EC/DEC=50/50 (v/v) as electrolyte A half-cell experiment was performed. A specific assembly process is shown in FIG. 41 and is as follows.

A lithium metal punched with a diameter of 10 mm was placed in the center of the case, and an appropriate pressure was applied to fix it to the case so as not to move. On it, 5 μL of electrolyte, a separator purchased from Celgard and punched to a diameter of 14 mm, electrolyte 10 μL, a working electrode punched to a diameter of 10 mm, electrolyte 5 μL, gasket, spacer, The springs were stacked one after the other and finally covered with a cap. The assembled cell was further sealed using a sealing machine and then mounted on a measuring device to observe the performance of the electrode. All assembly processes before attaching the cell to the measuring device were carried out in a glove box in an argon environment where moisture and oxygen were blocked.

The measurement was made in a current density of 1 A/g and a voltage range of 0.01 to 3.0 V, and the charge/discharge curves of the 1st, 2nd, 10th, and 100th cycles are shown in FIG. 15, and the cycle graph is shown in FIG. 16.

Example 5: carbon dioxide (CO ₂ ) from boron-doped porous carbon nanofibers (BPC/PAN CNF)-based lithium-ion battery negative electrode material

A method of manufacturing a porous carbon nanofiber-based lithium ion battery negative electrode material doped from carbon dioxide with boron is shown in FIG. 17 and will be described in detail as follows.

In this embodiment, polyacrylonitrile (PAN) and carbon dioxide were used as carbon precursors, and sodium borohydride (NaBH ₄ ) was used as a reducing agent of carbon dioxide and a boron precursor at the same time.

0.7 g of PAN was added to 7 g of dimethyl formamide (DMF) and stirred at 150 rpm for 2 hours at room temperature. After this, 70 mg of NaBH ₄ was further added and stirred again at 150 rpm for 1 hour to prepare a solution. The piston was removed from the syringe with a 21 gauge needle, and the solution made inside was transferred to the dropper. After reinserting the piston, remove the air inside the syringe to prevent the internal solution from leaking upwards with the needle. Electrospinning was performed by attaching a syringe containing the solution to the electrospinning test apparatus. In this case, the electrospinning conditions are as follows. The distance between the syringe needle and the collector was 13 cm, and it was set at an angle of 40 degrees horizontally from the collector. The solution was spun in the form of nanofibers on a collector at a flow rate of 0.8 mL/h at a voltage of 18 kV.

Carbon nanofibers with a diameter of 200 to 300 nm made by electrospinning are composed of NaBH ₄ and PAN, and are precursors of boron-doped porous carbon nanofibers (BPC/PAN CNF). At this time, the precursor nanofibers are in the form in which NaBH ₄ and PAN are evenly dispersed. The BPC/PAN precursor was placed in a crucible and placed in a furnace reactor, and nitrogen was flowed at a flow rate of 50 mL/min. At this time, the reaction conditions were raised from room temperature to 200 °C at a temperature increase rate of 5 °C/min, and the temperature was maintained for 3 hours. After that, the temperature was raised to 500 °C at 5 °C/min, and carbon dioxide was flowed at a flow rate of 75 ml/min to maintain the temperature for 2 hours. At this time, nitrogen does not flow in, only carbon dioxide flows. After 2 hours, the inflow of carbon dioxide was stopped, nitrogen was flowed at a flow rate of 50 mL/min, and the temperature was again raised to 750 °C at 5 °C/min and maintained for 1 hour. After cooling to room temperature, the resulting fibers were washed with deionized water (DIW). The cleaning process is as follows.

After 200 ml of distilled water was poured into a 200 ml beaker containing the reaction sample, the mixture was stirred at 150 rpm for 2 hours at room temperature. At this time, if the stirring speed is too fast, the fiber is damaged and the shape for making the electrode cannot be maintained, so the stirring speed is limited to 150 rpm. After that, the sample is allowed to settle and the solution above is removed. After repeating this step twice, the sample was dried in an oven at 70° C. for more than 12 hours. The boron-doped porous carbon nanofibers prepared in this way are directly manufactured as a negative electrode by a punching machine with a size of 10 mm without a conductive material, binder, or current collector.

A lithium-ion battery measurement experiment was performed by assembling a half-cell of the completed boron-doped porous carbon nanofiber (BPC/PAN CNF) confirmable in FIG. 18 in the same manner as in Example 4. As the experimental conditions, it was measured in a current density of 1 A/g and a voltage range of 0.01 to 3.0 V, and the charge/discharge curves of the 1st, 2nd, 10th, and 100th cycles are shown in FIG. 19 and the cycle curves are shown in FIG. 20 .

Example 6: Carbon dioxide (CO) containing silicon (Si) ₂ ) from boron-doped porous silicon-carbon nanofibers (Si/BPC/PAN CNF)-based lithium-ion battery negative electrode material fabrication

A method of manufacturing a porous silicon-carbon nanofiber-based lithium ion battery negative electrode material doped from carbon dioxide containing silicon with boron is shown in FIG. 21 and will be described in detail as follows.

In this embodiment, polyacrylonitrile (PAN) and carbon dioxide were used as carbon precursors, and sodium borohydride (NaBH ₄ ) was used as a reducing agent of carbon dioxide and a boron precursor at the same time. Silicon of silicon-carbon nanofibers was purchased from US Research Nanomaterials and used.

0.7 g of PAN was added to 7 g of dimethyl formamide (DMF) and stirred at 150 rpm for 2 hours at room temperature. After this, 70 mg of NaBH ₄ was further added and completely dissolved by stirring again at 150 rpm for 1 hour at room temperature, 14 mg of silicon nanoparticles were added, and the mixture was physically mixed by stirring at 150 rpm for 1 hour. The piston was removed from the syringe with a 21 gauge needle, and the solution made inside was transferred to the dropper. After reinserting the piston, the air inside the syringe was removed to prevent the internal solution from leaking upward toward the needle. Electrospinning was performed by attaching a syringe containing the solution to the electrospinning test apparatus.

In this case, the electrospinning conditions are as follows. The distance between the syringe needle and the collector was 13 cm, and it was set at an angle of 40 degrees horizontally from the collector. The solution was spun in the form of nanofibers on the collector at a flow rate of 1.5 mL/h at a voltage of 18 kV.

Carbon nanofibers with a diameter of 200 to 300 nm made by electrospinning are composed of silicon, sodium borohydride, and PAN, and are precursors of Si/BPC/PAN. The precursor of Si/BPC/PAN was placed in a crucible and placed in a furnace reactor, and nitrogen was flowed at a flow rate of 50 mL/min. At this time, the reaction conditions were raised from room temperature to 200 °C at a temperature increase rate of 5 °C/min, and the temperature was maintained for 3 hours. After that, the temperature was raised to 500 °C at 5 °C/min, and carbon dioxide was flowed at a flow rate of 75 ml/min to maintain the temperature for 2 hours. At this time, nitrogen is not introduced, only carbon dioxide flows. After 2 hours, the inflow of carbon dioxide was stopped, nitrogen was flowed at a flow rate of 50 mL/min, and the temperature was again raised to 750 °C at 5 °C/min and maintained for 1 hour. After cooling to room temperature, the resulting fibers were washed with deionized water (DIW). The cleaning process is as follows.

After 200 ml of distilled water was poured into a 200 ml beaker containing the reaction sample, the mixture was stirred at 150 rpm at room temperature for 1 hour. At this time, if the stirring speed is too fast, the fiber is damaged and the shape for making the electrode cannot be maintained, so the stirring speed is limited to 150 rpm. After that, the sample is allowed to settle and the solution above is removed. After repeating this step twice, the sample was dried in an oven at 70° C. for more than 12 hours. The completed boron-doped porous silicon-carbon nanofibers (Si/BPC/PAN), which can be confirmed in FIG. 22, are punched with a diameter of 10 mm by a punching machine without mixing with a conductive material, a binder, and a current collector to form an electrode in a lithium-ion battery. was used as

The completed Si/BPC/PAN CNF was assembled with half cells in the same manner as in Example 4, and a lithium-ion battery measurement experiment was performed. As the experimental conditions, it was measured in a current density of 1 A/g and a voltage range between 0.01 V - 3.0 V, and the charge/discharge curves of the 1st, 2nd, 10th, and 100th cycles are shown in FIG. 23, and the cycle curve is shown in FIG. it was

Example 7: carbon dioxide (CO ₂ ) and cobalt oxide/porous carbon composites (CO/PC) generated from cobalt precursors.

Junsei chemical's cobalt acetate tetrahydrate (Co(CH ₃ COO) ₂ .4H ₂ O)) was used as a cobalt oxide precursor, and Sigma Aldrich's sodium borohydride (NaBH ₄ ) was used as a reducing agent. was used, and carbon dioxide served as a carbon precursor and an oxidizing agent for a cobalt precursor. The manufacturing method is shown in FIG. 25, and is specifically described as follows.

First, 1 g of cobalt acetate tetrahydrite was dissolved in 2 ml of DI water, and then dried in an oven at 100° C. to remove hydrates as much as possible. The hydrated cobalt acetate was mixed evenly with 1 g of sodium boron hydride using a pestle and mortar, put in a crucible, and put in a crucible in a furnace reactor set at 80 °C, argon (Ar) gas 50 ml/ min was flowed for 30 min to create an argon environment, and then the temperature was raised. The temperature was raised to 400 °C at a temperature increase rate of 2 °C/min, and when it reached 400 °C, the gas was converted from argon to carbon dioxide (CO ₂ ) gas at a rate of 5 °C/min and 500 °C at a temperature increase rate of 5 °C/min. After raising the temperature further, the temperature was maintained for 2 hours. The gas and flow rates were maintained until the temperature was reduced to room temperature.

After the reaction was completed, the sample was transferred to a 250 ml beaker, 200 ml of DI water was poured, and then stirred at 80° C. for 1 hour at 500 rpm. Thereafter, the solution except for the sample was removed through a reduced pressure filter device. This step was repeated 4 more times. Finally, the process was repeated one more time at room temperature using ethanol, and the sample was dried in an oven at 80° C. for more than 24 hours.

A cobalt oxide/porous carbon composite (CO/PC) generated from carbon dioxide was used as an electrode material for a lithium-ion battery. The specific process is as follows.

오븐에서 24 시간 이상 건조시켜 NMP 용매를 증발시켰다.Put 30 mg of polyvinylidene fluoride (poly-1,1-difluoroethene, PVDF) and 2.0 ml of methylpyrrolidone (N-Methyl-2-pyrrolidone, NMP) in a 10 ml vial, and stir at 1000 rpm for 1 hour. A mixed solution was prepared. After evenly mixing 90 mg of CO/PC and 30 mg of carbon black, it was put into the previously prepared PVDF and NMP mixed solution and stirred at 1000 rpm for 24 hours. Take out the mixture in the form of a slurry made in this way and apply it flat on a copper foil, 70

The NMP solvent was evaporated by drying in an oven for at least 24 hours.

A measurement experiment was performed by assembling the half-cell of the electrode made as above in the same manner as in Example 1. As a result of the experiment, the charging and discharging curves and cycle curves shown in FIGS. 27 and 28 were obtained, and from these, a voltage range of 0.01 V - 3.0 V and a current density of 1 A/g, an electric capacity of 1000 mAh/g was confirmed to be maintained for more than 300 cycles.

Example 8: carbon dioxide (CO ₂ ) and manganese oxide/porous carbon composite (MO/PC) generated from a manganese precursor, lithium-ion battery negative electrode material manufacturing

Sigma Aldrich's manganese acetate tetrahydrate (Mn(CH ₃ COO) ₂ .4H ₂ O)) was used as a manganese oxide precursor, and Sigma Aldrich's sodium borohydride (NaBH ₄ ) was used as a reducing agent. was used, and carbon dioxide served as a carbon precursor and an oxidizing agent for a manganese precursor. The manufacturing method is shown in FIG. 29, and is specifically described as follows.

0.25 g of manganese acetate tetrahydrite and 0.25 g of sodium boron hydride were put in a 10 ml vial, mixed evenly, and placed in a crucible. The crucible was put in a furnace reactor set at 200 °C, and 50 ml/min of argon (Ar) gas was flowed for 30 min to create an argon environment, and then the temperature was raised. The temperature was raised to 400 °C at a temperature increase rate of 2 °C/min, and when it reached 400 °C, the gas was converted from argon to carbon dioxide (CO ₂ ) gas at a rate of 5 °C/min and 500 °C at a temperature increase rate of 5 °C/min. After raising the temperature further, the temperature was maintained for 2 hours. The gas and flow rates were maintained until the temperature was reduced to room temperature.

After the reaction was completed, the sample was transferred to a 250 ml beaker, 200 ml of DI water was poured, and then stirred at 80° C. for 1 hour at 500 rpm. Thereafter, the solution except for the sample was removed through a reduced pressure filter device. This step was repeated 4 more times. Finally, the process was repeated one more time at room temperature using ethanol, and the sample was dried in an oven at 80° C. for more than 24 hours.

Manganese oxide/porous carbon composite (MO/PC) generated from carbon dioxide was used as an electrode material for a lithium-ion battery. The specific process is as follows.

오븐에서 24 시간 이상 건조시켜 NMP 용매를 증발시켰다.Put 20 mg of polyvinylidene fluoride (poly-1,1-difluoroethene, PVDF) and 2.0 ml of methylpyrrolidone (N-methyl-2-pyrrolidone, NMP) in a 10 ml vial and stir at 1000 rpm for 1 hour. A mixed solution was prepared. After mixing 60 mg of MO/PC and 20 mg of carbon black evenly, it was put into the previously prepared PVDF and NMP mixed solution and stirred at 1000 rpm for 24 hours. Take out the mixture in the form of a slurry made in this way and apply it flat on a copper foil, 70

The NMP solvent was evaporated by drying in an oven for at least 24 hours.

A measurement experiment was performed by assembling the half-cell of the electrode made as above in the same manner as in Example 1. As a result of the experiment, the charging and discharging curves and cycle curves are shown in FIGS. 31 and 32, and from this, the electric capacity of 600 mAh/g based on the voltage range of 0.01-3.0 V and the current density of 1 A/g is 50 It was confirmed that the cycle was maintained.

Example 9: carbon dioxide (CO ₂ ) and iron oxide/porous carbon composites (FeO/PC) generated from iron precursors.

Sigma Aldrich's iron chloride (FeCl ₃ ) was used as an iron oxide precursor, and Sigma Aldrich's sodium borohydride (NaBH ₄ ) was used as a reducing agent, and carbon dioxide served as a carbon precursor and an oxidizing agent for the iron precursor did The manufacturing method is shown in FIG. 33, and is specifically described as follows.

0.25 g of iron chloride and 0.25 g of sodium boron hydride were put in a 10 ml vial, mixed evenly, and placed in a crucible. The crucible was put in a furnace reactor set at 200 °C, and 50 ml/min of argon (Ar) gas was flowed for 30 min to create an argon environment, and then the temperature was raised. The temperature was raised to 400 °C at a temperature increase rate of 2 °C/min, and when it reached 400 °C, the gas was converted from argon to carbon dioxide (CO ₂ ) gas at a rate of 5 °C/min and 500 °C at a temperature increase rate of 5 °C/min. After raising the temperature further, the temperature was maintained for 2 hours. The gas and flow rates were maintained until the temperature was reduced to room temperature.

After the reaction was completed, the sample was transferred to a 250 ml beaker, 200 ml of DI water was poured, and then stirred at 80° C. for 1 hour at 500 rpm. Thereafter, the solution except for the sample was removed through a reduced pressure filter device. This step was repeated 4 more times. Finally, the process was repeated one more time at room temperature using ethanol, and the sample was dried in an oven at 80° C. for 24 hours or more.

An iron oxide/porous carbon composite (FeO/PC) generated from carbon dioxide was used as an electrode material for a lithium-ion battery. The specific process is as follows.

Put 30 mg of polyvinylidene fluoride (poly-1,1-difluoroethene, PVDF) and 2.0 ml of methylpyrrolidone (N-methyl-2-pyrrolidone, NMP) in a 10 ml vial, and stir at 1000 rpm for 1 hour. A mixed solution was prepared. After evenly mixing FeO/PC 90 mg and carbon black 30 mg, it was put into the previously prepared PVDF and NMP mixed solution and stirred at 1000 rpm for 24 hours. The mixture in the form of a slurry prepared in this way was taken out, applied flatly on a copper foil, and dried in an oven at 70° C. for more than 24 hours to evaporate the NMP solvent.

A measurement experiment was performed by assembling the half-cell of the electrode made as above in the same manner as in Example 1. As a result of the experiment, the charging and discharging curves and cycle curves are shown in FIGS. 35 and 36. From this, the electric capacity of 600 mAh/g was 80 based on a voltage range of 0.01 to 3.0 V and a current density of 1 A/g. It was confirmed that the cycle was maintained.

Example 10: carbon dioxide (CO ₂ ) production of a lithium-ion battery negative electrode interlayer (BPC/PAN Interlayer) based on boron-doped carbon nanofibers from

A method of manufacturing an anode intermediate layer of a lithium ion battery based on carbon nanofibers doped with boron from carbon dioxide is shown in FIG. 37 , and will be described in detail as follows.

In this embodiment, polyacrylonitrile (PAN) and carbon dioxide were used as carbon precursors, and sodium borohydride (NaBH ₄ ) was used as a reducing agent of carbon dioxide and a boron precursor at the same time.

In the same manner as in Example 5, an electrospinning solution was prepared and electrospinning was performed to obtain a carbon nanofiber precursor, and heat treatment was performed under the same conditions of temperature increase rate, gas flow rate, and temperature range, and the washing process was performed in the same manner. .

The boron-doped carbon nanofibers produced in this way can be seen in FIG. 38 , and were punched out in a circular shape with a diameter of 14 mm and immediately used as an anode interlayer (BPC/PAN interlayer) of a lithium ion battery.

Silicon nanoparticles were used as anode material, and the specific process is as follows. 20 mg of polyacrylic acid (PAA) and 3 ml of methylpyrrolidone (N-Methyl-2-pyrrolidone, NMP) were put in a 20 ml vial and stirred at 500 rpm for 24 hours to make a mixed solution. After mixing 160 mg of silicon nanoparticles and 20 mg of carbon black using a pestle and mortar and pestle, it was put into the previously prepared PAA and NMP mixed solution and stirred at 1000 rpm for 24 hours. The mixture in the form of a slurry thus prepared was taken out, applied flatly on a copper foil, and dried in an oven at 70° C. for more than 24 hours to evaporate the NMP solvent.

The electrode prepared as above was used as a working electrode (WE), and lithium metal (Li metal) was used as a counter electrode (CE) and a standard electrode (SE), and the A carbon nanofiber-based interlayer (BPC/PAN interlayer) is used as an interlayer between the separator and the working electrode, and an organic electrolyte 1 M lithium hexafluorophosphate solution in ethyl carbonate and diethyl carbonate, 1.0 M LiPF6 in EC /DEC=50/50 (v/v)) was used as an electrolyte to conduct a coin-cell type lithium-ion battery half-cell experiment. The detailed assembly process is as follows.

A lithium metal punched with a diameter of 10 mm was placed in the center of the case, and an appropriate pressure was applied to fix it to the case so as not to move. On top of that, 5 μL of electrolyte, a separator purchased from Celgard and punched with a diameter of 14 mm, 10 μL of electrolyte, an interlayer punched with a diameter of 14 mm, a working electrode punched with a diameter of 10 mm, a gasket, and a spacer (spacer) and spring (spring) stacked one after another, and finally covered with a cap (cap). The assembled cell was further sealed using a sealing machine and then mounted on a measuring device to observe the performance of the electrode. All assembly processes before attaching the cell to the measuring device were carried out in a glove box in an argon environment where moisture and oxygen were blocked.

As a result of the experiment, as shown in FIGS. 39 and 40, charge-discharge curves and cycle curves were obtained, and based on a voltage range of 0.01 to 1.5 V and a current density of 1 A/g, no interlayer was added. It was confirmed that the storage capacity (about 650 mAh/g) higher than that of 150 mAh/g was exhibited for more than 50 cycles.

As the specific parts of the present invention have been described in detail above, it will be clear to those of ordinary skill in the art that these specific descriptions are only preferred embodiments, and the scope of the present invention is not limited thereby. will be. Accordingly, it is intended that the substantial scope of the invention be defined by the claims and their equivalents.

Claims (30)

delete (a) supplying the carbon dioxide-containing gas, boron precursor and nitrogen precursor at a flow rate of 200 mlmin ^-1 or less in an inert gas atmosphere to 400 to 700° C. at a rate of 1 to 10° C. min ^-1 producing a carbon material doped with nitrogen; and
(b) mixing a conductive material and a binder solution with the carbon material doped with boron and nitrogen, and then evaporating the solvent from the resulting slurry.
(a) a carbon dioxide-containing gas and a carbon precursor, a boron precursor or a boron precursor and a nitrogen precursor and a silicon-containing material in an atmosphere of an inert gas while supplying the carbon dioxide at a flow rate of 200 mlmin ^-1 or less at a rate of 1 to 10 ℃ min ^-1 Heating to 400 ~ 700 ℃ furnace to prepare a silicon-carbon composite; and
(b) mixing a conductive material and a binder solution with the silicon-carbon composite, and then evaporating the solvent from the resulting slurry.
(a) recrystallizing or electrospinning a mixture of a carbon precursor, a nitrogen precursor, or a boron precursor to form a carbon nanofiber precursor;
(b) producing carbon nanofibers by oxidizing and carbonizing the carbon nanofiber precursor while supplying a carbon dioxide-containing gas, under the condition that an inert gas is introduced at a flow rate of 20 to 200 ml/min; carbonizing or oxidizing the carbon precursor by increasing the temperature at a rate and maintaining the temperature at 200 to 1200 °C for 0.5 to 5 hours, and introducing the carbon dioxide at a flow rate of 50 to 200 ml/min at 300 to 600 °C; and
(c) a method of manufacturing a carbon negative electrode for a lithium ion battery comprising the step of evaporating the solvent from the carbon nanofibers.
(a) recrystallizing or electrospinning a carbon precursor, a nitrogen precursor or a mixture of a boron precursor and a silicon-containing material to form a silicon-carbon nanofiber precursor; and
(b) oxidizing and carbonizing the silicon-carbon nanofiber precursor while supplying a carbon dioxide-containing gas to produce a silicon-carbon nanofiber composite, but under the condition that an inert gas is introduced at a flow rate of 20-200 ml/min. It is heated at a rate of 10 ℃/min and maintained at 200-1200 ℃ for 0.5-5 hours, and the carbon dioxide is introduced at 300-600 ℃ at a flow rate of 50-200 ml/min to carbonize or oxidize the carbon precursor. step; and
(c) the silicon-carbon nanofiber composite;
(a) a carbon precursor, a nitrogen precursor, or a mixture of a boron precursor and a metal oxide precursor is heated to 400 to 700 ° C at a rate of 1 to 10 ° C min ^-1 while supplying a gas containing carbon dioxide, 20 to 200 ml / At the flow rate of min, the temperature is raised at a rate of 1 to 10 ° C, maintained at 200 to 1200 ° C for 0.5 to 5 hours, and carbon dioxide is introduced at 300 to 600 ° C at a flow rate of 50 to 200 ml/min to form a carbon precursor synthesizing a metal oxide-porous carbon composite by oxidizing the metal oxide precursor at the same time as carbonization of the; and
(b) mixing a conductive material and a binder solution in the metal oxide-carbon composite, and then evaporating the solvent from the resulting slurry.
delete delete The lithium ion battery from carbon dioxide according to claim 4 or 5, wherein the carbon nanofiber or the silicon-carbon nanofiber composite is mixed with a conductive material and a binder solution, and then the solvent is evaporated from the resulting slurry. A method of manufacturing a carbon anode for use.
[Claim 7] According to any one of claims 3 to 6, wherein the carbon precursor is at least one selected from the group consisting of gas, amorphous carbon material, crystalline carbon material, and polymer material. manufacturing method.
11. The method of claim 10, wherein the carbon precursor is carbon dioxide (CO ₂ ); activated carbon, carbon black, charcoal; graphite, graphene; A method of manufacturing a carbon cathode for a lithium ion battery, characterized in that at least one selected from the group consisting of polyacrylonitrile (PAN) and polyaniline (PANI).
According to any one of claims 2 to 6, wherein the boron precursor is boron oxide (B ₂ O ₃ ), boric acid (H ₃ BO ₃ ), lithium borohydride (LiBH ₄ ), sodium borohydride ( NaBH ₄ ), Potassium Borohydride (KBH ₄ ), Magnesium Borohydride (Mg(BH ₄ ) ₂ ), Calcium Borohydride (Ca(BH ₄ ) ₂ ), Strontium Borohydride (Sr(BH ₄ ) ₂ ) ) and ammonia borane (NH ₃ BH ₃ ) A method of manufacturing a carbon cathode for a lithium ion battery, characterized in that at least one selected from the group consisting of.
7. The method according to any one of claims 2 to 6, wherein the nitrogen precursor is polypyrrole, polyaniline, melamine (C ₃ H ₆ N ₆ ), PDI(N,N′-bis(2) ,6-diisopropyphenyl)-3,4,9,10-perylenetetracarboxylicdiimide), polyacrylonitrile (PAN), urea (CO(NH ₂ ) ₂ ), ammonia (NH ₃ ), ammonia hydroxide (NH ₄ OH) , hydrazine (N ₂ H ₄ ), ammonia borane (NH ₃ BH ₃ ) and nitrogen gas (N ₂ ) A method of manufacturing a carbon cathode for a lithium ion battery, characterized in that at least one selected from the group consisting of.
According to claim 3 or 5, wherein the silicon-containing material is silicon nanoparticles (Si nanoparticles), silicon dioxide (SiO ₂ ), silicon carbide (SiC), silicon tetrachloride (SiCl ₄ ), silicon nitride (Si ₃ N ₄ ) composed of silicon acetate (Si(OCOCH ₃ ) ₄ ), silicon tetrafluoride (SiF ₄ ), silicon tetrabromide (SiBr ₄ ), silicon monoxide (SiO) and tetraethyl orthosilicate (Si(OEt) ₄ ). A method of manufacturing a carbon cathode for a lithium ion battery, characterized in that at least one selected from the group.
The method of claim 6, wherein the metal oxide precursor is at least one selected from the group consisting of a cobalt oxide precursor, a manganese oxide precursor, and an iron oxide precursor.
The method of claim 15, wherein the cobalt oxide precursor is cobalt chloride (CoCl ₂ ), cobalt bromide (CoBr ₂ ), cobalt iodide (CoI ₂ ), carbonyl cobalt (Co ₂ (CO) ₈ ), cobalt acetate (cobalt) (II) acetate), cobalt naphthenate, cobalt nitrate (Co(NO ₃ ) ₂ ), cobalt sulfate (CoSO ₄ ) and at least one selected from the group consisting of cobalt acetylacetonate A method of manufacturing a carbon anode for a lithium-ion battery, characterized in that.
The method of claim 15, wherein the manganese oxide precursor is potassium permanganate (KMnO ₄ ), potassium manganate (K ₂ MnO ₄ ), barium manganate (BaMnO ₄ ), manganese chloride, manganese sulfate (manganese sulfate), manganese sulfide (manganese) sulfide, MnS), manganese(II) acetate, manganese(II) acetylacetonate, manganese(II) bromide, MnBr ₂ ), manganese(II) nitrate, Mn(NO ₃ ) ₂ ) A method of manufacturing a carbon cathode for a lithium ion battery, characterized in that at least one selected from the group consisting of.
The method according to claim 15, wherein the iron oxide precursor is iron chloride (II, FeCl ₂ ), iron chloride (III, FeCl ₃ ), iron bromide (FeBr ₂ ) iron iodide (iron (II) iodide, FeI ₂ ), iron sulfide (FeS) , iron disulfide (FeS ₂ ) and iron acetylacetonate (iron (III) acetylacetonate) manufacturing method of a carbon cathode for a lithium ion battery, characterized in that at least one selected from the group consisting of.
The carbon anode for lithium ion battery according to any one of claims 2 to 3 and 6, further comprising a washing step of washing with acid, water or alcohol after step (a). manufacturing method.
The method of claim 4 or 5, further comprising a washing step with acid, water or alcohol after step (b).
delete delete The method of claim 4 or 5, wherein the distance between the syringe needle and the collector is 10-15 cm, the radiation angle to the collector is 30-50 degrees horizontally, the operating voltage is 15-20 kV, and the radiation flow rate is 0.5 A method for producing a carbon cathode for a lithium ion battery, characterized in that electrospinning at ~2 mL/h.
Carbon for a lithium ion battery prepared by the method of any one of claims 2 to 6, characterized in that it is composed of a composite of carbon and at least one material selected from the group consisting of boron, nitrogen, silicon and metal oxides A method for manufacturing an anode.
(a) recrystallizing or electrospinning a mixture of a carbon precursor, a nitrogen precursor, or a boron precursor to form a carbon nanofiber precursor; and (b) oxidizing and carbonizing the carbon nanofiber precursor while supplying carbon dioxide-containing gas to produce carbon nanofibers, but at 1 to 10 ° C./ It is heated at a rate of min and maintained at 200 to 1200 ° C for 0.5 to 5 hours, and at 300 to 600 ° C. A method for manufacturing an intermediate layer between a separator for a lithium ion battery and a working electrode.
The method of claim 25, wherein the carbon precursor is at least one selected from the group consisting of gas, amorphous carbon material, crystalline carbon material, and polymer material.
26. The method of claim 25, wherein the carbon precursor is carbon dioxide (CO ₂ ); activated carbon, carbon black, charcoal; graphite, graphene; A method of manufacturing an intermediate layer between a separator for a lithium ion battery and a working electrode, characterized in that at least one selected from the group consisting of polyacrylonitrile (PAN) and polyaniline (PANI).
The method of claim 25, wherein the boron precursor is boron oxide (B ₂ O ₃ ), boric acid (H ₃ BO ₃ ), lithium borohydride (LiBH ₄ ), sodium borohydride (NaBH ₄ ), potassium borohydride (KBH ₄ ), magnesium borohydride (Mg(BH ₄ ) ₂ ), calcium borohydride (Ca(BH ₄ ) ₂ ), strontium borohydride (Sr(BH ₄ ) ₂ ), and ammoniaborane (NH ₃ ) BH ₃ ) A method of manufacturing an intermediate layer between a separator for a lithium ion battery and a working electrode, characterized in that at least one selected from the group consisting of.
26. The method of claim 25, wherein the nitrogen precursor is polypyrrole, polyaniline, melamine (C ₃ H ₆ N ₆ ), PDI (N,N'-bis(2,6-diisopropyphenyl)-3 ,4,9,10-perylenetetracarboxylicdiimide), polyacrylonitrile (PAN), urea (CO(NH ₂ ) ₂ ), ammonia (NH ₃ ), ammonia hydroxide (NH ₄ OH), hydrazine (N ₂ H ₄ ), ammonia borane (NH ₃ BH ₃ ) and nitrogen gas (N ₂ ) A method of manufacturing an intermediate layer between a separator for a lithium ion battery and a working electrode, characterized in that at least one selected from the group consisting of.
The method of claim 25, wherein the carbon nanofibers are used in the form of a free-standing interlayer, a separator-attached interlayer, or an anode-attached interlayer attached to the cathode. A method for manufacturing an intermediate layer between a separator for a lithium ion battery and a working electrode, characterized in that.

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