WO2015105223A1

WO2015105223A1 - Organic-inorganic composite porous separation membrane, production method for same, and electrochemical device comprising same

Info

Publication number: WO2015105223A1
Application number: PCT/KR2014/000441
Authority: WO
Inventors: 박종혁
Original assignee: 성균관대학교산학협력단
Priority date: 2014-01-13
Filing date: 2014-01-15
Publication date: 2015-07-16
Also published as: KR20150084337A

Abstract

The present invention relates to a production method for an organic-inorganic composite porous separation membrane, an organic-inorganic composite porous separation membrane produced according to the method, and an electrochemical device comprising the organic-inorganic composite porous separation membrane.

Description

Organic-inorganic composite porous separator, method for preparing the same, and electrochemical device comprising the same

The present application relates to an organic-inorganic composite porous separator, an organic-inorganic composite porous separator prepared according to the method, and an electrochemical device including the organic-inorganic composite porous separator.

In the early 21st century, IT industry technology, which was developed around portable and simple mobile devices such as laptops and mobile phones, has been steadily developed by converging with various science and technology fields. With the emergence of various high-performance applications due to convergence, hybrid cars and electronic vehicles, which are eco-friendly vehicles, have emerged, and attention has been focused on electrochemical devices as their energy sources. Among these devices, a lithium ion secondary battery, which is a type of secondary battery capable of repeating charging and discharging by using a reversible interconversion of chemical energy and electrical energy, has been attracting attention, and in developing such electrochemical devices, miniaturization and weight reduction The research and development of the design of new electrodes and batteries to meet the characteristics of high capacity, high output / high stability are underway.

A lithium ion secondary battery is composed of a positive electrode, a negative electrode, an electrolyte, and a separator, and may be classified into a lithium ion battery and a lithium ion polymer battery according to the type of electrolyte. Lithium ion batteries, in which lithium ions are transferred through an electrolyte solution, introduce a liquid organic electrolyte containing lithium salts, thereby accelerating battery assembly and improving ion conductivity at room temperature. It is slightly weakened, and there is a possibility of ignition / explosion due to an increase in the pressure in the battery case due to chemical reactions during electrode corrosion and overcharging, and a protection circuit is necessary to rethink the problem of stability. On the other hand, lithium ion polymer batteries have a good durability against internal chemical reactions due to overcharge / over discharge using lithium ion conductive polymers as gels or solid electrolytes, allowing them to be designed in various sizes and designs without the risk of ignition and explosion. It is one of the next generation batteries. However, since the polymer electrolyte has a lower ion conductivity than a lithium ion battery using a liquid electrolyte, the resistance inside the battery is high, which is disadvantageous for a large current discharge. .

In the electrochemical device as described above, as the potential risk of safety accidents such as ignition and explosion accidents of the electrochemical device has rapidly increased, the safety evaluation and safety of the electrochemical device have emerged as a very important issue. Accordingly, as the demand for safety verification not only at the national level but also at the consumer level is increasing worldwide, the government is enforcing and expanding the mandatory certification regulations and standardizing technology. Such an electrochemical device may cause a malfunction depending on the operating environment.In case of malfunction, a thermal runaway occurs due to overheating, and when a separator provided in the device is decomposed, electrical energy is released due to the potential difference of the electrode, which is rapidly narrowed due to an internal short circuit. There is a fear that internal explosion may be caused by vaporization of the electrolyte solution.

In this regard, Korean Patent Laid-Open Publication No. 10-2006-72065, 10-2008-0010166, etc. propose a separator in which a porous coating layer formed of a mixture of inorganic filler particles and a polymer binder is formed on one or both surfaces of a porous substrate. It became. The inorganic filler particles of the microporous coating layer formed on the porous substrate serve as a kind of passivation to maintain physical shape, thereby suppressing thermal shrinkage of the porous substrate upon overheating due to malfunction of the electrochemical device, and Together, an empty space exists between the inorganic filler particles to form fine pores.

As such, the microporous coating layer formed on the porous substrate contributes to improving the safety of the electrochemical device. When the inorganic filler particles used to form the microporous coating layer according to the prior art are mixed and used together with the polymer binder, the inorganic particles and the polymer may be mixed as well as a potential problem that a small amount of the polymer binder may melt or deform at a high temperature. In order to secure the thermal properties at high temperatures, the use of a large amount of inorganic particles and the thickness of the inorganic coating layer at the micrometer level are accompanied, so that the membrane characteristics of the thin film capable of high-density filling for high capacity are insufficient. have.

Accordingly, the present application is to provide an electrochemical device comprising a method for producing an organic-inorganic composite porous separator, an organic-inorganic composite porous separator prepared according to the method, and the organic-inorganic composite porous separator.

However, the problem to be solved by the present application is not limited to the above-mentioned problem, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

A first aspect of the present application is to coat an inorganic precursor on a porous polymer substrate using a solution process; Converting the coated inorganic precursor into an inorganic oxide by energy irradiation to form a porous polymer substrate having an inorganic oxide thin film formed thereon; And forming a metal oxide thin film on the inorganic oxide thin film formed on the porous polymer substrate by using atomic layer deposition (ALD).

A second aspect of the present application provides an organic-inorganic composite porous separator prepared by the method according to the first aspect of the present application.

A third aspect of the present application provides an electrochemical device including an organic-inorganic composite porous separator, a positive electrode, a negative electrode, and an electrolyte according to the second aspect of the present application.

According to the method of manufacturing an organic-inorganic composite porous separator according to the present invention, by using a solution process, one or more inorganic oxide thin films may be formed on the outer surface and the surface of the inner pores of the porous polymer substrate, thereby improving heat resistance of the separator. By using the ALD process to form a metal oxide in the improved thermal stability by improving the quality of the separator, there is an effect that can reduce the side reaction of the electrolyte by the inorganic oxide thin film formed first.

In general, the substrate used as a substrate of the separator is a polymer material, and has a disadvantage in that it is vulnerable to heat. When the ALD process is performed without forming the inorganic oxide thin film, the ALD process can only be performed at a low temperature. Although the quality may be low, the separator according to the present invention may be heat-resistant by the inorganic oxide thin film formed first, and then may perform the ALD process at a higher temperature, thereby producing a qualitatively improved separator.

The organic-inorganic composite porous separator according to the present invention has a high stability to prevent internal short circuits by securing a high lithium ion diffusivity within the pore structure by applying an inorganic oxide thin film and improving thermal characteristics at high temperature. It is possible to assemble a battery, thereby manufacturing an electrochemical device such as a highly stable lithium secondary battery. In addition, by having a continuous porous structure that is suitable for the proper mechanical properties and mobility of ions, it is possible to secure excellent ionic conductivity characteristics.

The organic-inorganic composite porous separator according to the present invention has one or more inorganic oxide thin films formed by using a solution process and an ALD process, thereby overcoming the limitations of shape retention and mechanical properties at high temperatures of conventional commercially available polymer separators. At the same time it is possible to have a thin thickness capable of high density filling for high capacity.

1 is a schematic process diagram of a method of manufacturing an organic-inorganic composite porous separator according to one embodiment of the present application.

Figure 2 is a schematic diagram of the organic-inorganic composite porous separator according to an embodiment of the present application.

FIG. 3A is a field emission microscope (FE-SEM) photograph of the surface of a separator according to a comparative example of the present application. FIG.

Figure 3b is a FE-SEM picture of the surface of the separator according to a comparative example of the present application.

Figure 3c is a FE-SEM picture of the surface of the separator according to an embodiment of the present application.

Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present disclosure. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted for simplicity of explanation, and like reference numerals designate like parts throughout the specification.

Throughout this specification, when a portion is "connected" to another portion, this includes not only "directly connected" but also "electrically connected" with another element in between. do.

Throughout this specification, when a member is located "on" another member, this includes not only when one member is in contact with another member but also when another member exists between the two members.

Throughout this specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding the other components unless specifically stated otherwise.

As used throughout this specification, the terms "about", "substantially" and the like are used at, or in the sense of, numerical values when a manufacturing and material tolerance inherent in the stated meanings is indicated, Accurate or absolute figures are used to assist in the prevention of unfair use by unscrupulous infringers.

As used throughout this specification, the term "step to" or "step of" does not mean "step for."

Throughout this specification, the term "combination (s) thereof" included in the representation of a makushi form refers to one or more mixtures or combinations selected from the group consisting of the components described in the representation of makushi form, It means to include one or more selected from the group consisting of the above components.

Throughout this specification, the description of "A and / or B" means "A or B, or A and B."

Hereinafter, embodiments of the present disclosure have been described in detail, but the present disclosure may not be limited thereto.

The solution process according to the present application may be performed using a solution including the inorganic precursor, but may not be limited thereto.

In one embodiment of the present application, the manufacturing method may include, but not limited to, further comprising the step of plasma processing the porous polymer substrate before the coating of the inorganic precursor. In general, since the surface of the porous polymer substrate is hydrophobic, the coating of the hydrophilic precursor may not be uniform unless surface modification is performed through plasma treatment. For example, the porous polymer substrate may be treated with plasma to form a hydroxyl group on the porous polymer substrate, but may not be limited thereto.

Coating the inorganic precursor on the porous polymer substrate is a method of simultaneously improving the thermal properties while inheriting the excellent mechanical properties of the existing polymer membrane, and if the chemical solution process manufacturing method for producing a separator coated with the inorganic oxide thin film of the thin film without limitation Can be used.

In one embodiment of the present application, the energy irradiation may include, but is not limited to, irradiating heat, plasma, ultraviolet (UV), or laser. For example, the energy may include UV or UV-ozone, but may not be limited thereto. By the energy irradiation, one or more of the inorganic precursors are decomposed and converted into the inorganic oxide through a chemical reaction occurring on the surface of the porous substrate.

In one embodiment of the present application, the inorganic precursor may be coated on the surface of the outer surface and the inner pores of the porous polymer substrate, but may not be limited thereto. Accordingly, the inorganic precursor may be converted into an inorganic oxide by energy irradiation to form an inorganic oxide thin film on the outer surface and the surface of the inner pores of the porous polymer substrate.

In one embodiment of the present invention, the thickness of the inorganic precursor coated on the outer surface and the surface of the inner pores of the porous polymer substrate is about 1/2 of the size of the pores included in the porous polymer substrate (about 1/2 Up to a thickness). For example, the coated thickness of the inorganic precursor is less than about 5 μm, less than about 4 μm, less than about 3 μm, less than about 2 μm, less than about 1 μm, less than about 900 nm, less than about 800 nm, about 700 nm. Less than about 600 nm, less than about 500 nm, less than about 400 nm, less than about 300 nm, less than about 200 nm, less than about 100 nm, less than about 50 nm, less than about 10 nm, or less than about 5 nm. But may be coated. This may not be limited. The thickness of the inorganic oxide thin film may be about 1 nm or more, and when the thickness is less than about 1 nm, there is a concern that the thermal characteristics of the separator at high temperature may not be maintained.

In one embodiment of the present application, the porous polymer substrate may have a porosity of about 5% to about 95%, but may not be limited thereto. For example, the porous polymeric substrate is about 5% to about 95%, about 10% to about 80%, about 20% to about 70%, about 30% to about 60%, about 40% to about 50%, about 5% to about 50%, about 5% to about 40%, about 5% to about 30%, about 5% to about 20%, about 50% to about 95%, about 60% to about 95%, about 70% To about 95%, or about 80% to about 95% porosity, but may not be limited thereto.

In one embodiment of the present invention, the step of coating the inorganic precursor on the porous polymer substrate using the solution process, the first inorganic precursor is coated on the porous polymer substrate through a solution process and then heat treated and the second inorganic precursor It may be to include additional coating, but may not be limited thereto. The heat treatment may be performed at a temperature sufficient to dry the coated first inorganic precursor through a solution process.

In one embodiment of the present application, the porous polymer substrate according to the present invention is a polymer having a structure in which ions are easy to move, and has a high porosity and relatively uniform pore size distribution that facilitates mobility of lithium ions between both electrodes. Any one having a porous structure can be used without limitation. For example, the porous substrate may be a non-woven fabric formed of a porous net structure by the intersection of nanofibers, or may include a polyolefin-based substrate prepared by an elongation process, which is usually a material of a separator of an electrochemical device. This may not be limited.

In one embodiment of the present application, the porous polymer substrate is polyethylene, high density polyethylene, low density polyethylene, linear low density polyethylene, high molecular weight polyethylene, polypropylene terephthalate (polypropyleneterephthalate), polyethylene terephthalate (polyethyleneterephthalate), polybutylene tere Phthalate, polybutyleneterephthalate, polyester, polyacetal, polyamide, polycarbonate, polyimide, polyetheretherketone, polyethersulfone, Polyphenylene oxide (polyphenylene oxide), polyphenylene sulfide (polyphenylenesulfide), polyethylenenaphthalene (polyethylenenaphthalene), and may include those selected from the group consisting of, but may not be limited thereto.

In one embodiment of the present application, the inorganic oxide may include one selected from the group consisting of an inorganic oxide having a dielectric constant of about 5 or more, an inorganic oxide having lithium ion transfer ability, and combinations thereof, but is not limited thereto. It may not be.

In one embodiment of the present application, the inorganic oxide having a dielectric constant of about 5 or more is SiO ₂ , BaTiO ₃ , Pb (Zr, Ti) O ₃ (PZT), hafnia (HfO ₂ ), SrTiO ₃ , CeO ₂ , MgO, NiO, CaO, ZnO, ZrO ₂ , Y ₂ O ₃ , Al ₂ O ₃ , TiO ₂ , SiC, and may be selected from the group consisting of a combination thereof, but may not be limited thereto. . The inorganic oxide may contribute to an increase in dissociation degree of the electrolyte salt, for example, lithium salt in the liquid electrolyte, thereby improving the ionic conductivity of the electrolyte solution. The inorganic oxide may be an inorganic oxide having a dielectric constant of about 5 or more, for example, about 10 or more, but may not be limited thereto.

In one embodiment of the present application, the porous polymer substrate may have a thickness of about 1 μm to about 100 μm, but may not be limited thereto. For example, the porous polymer substrate may have a thickness of about 1 μm to about 100 μm, about 5 μm to about 100 μm, about 10 μm to about 100 μm, about 15 μm to about 100 μm, about 1 μm to about 90 μm About 1 μm to about 80 μm, about 1 μm to about 70 μm, about 1 μm to about 60 μm, about 1 μm to about 50 μm, about 1 μm to about 40 μm, or about 5 μm to about 40 μm It may be, but may not be limited thereto.

In one embodiment of the present application, the pore size of the porous polymer substrate may be about 0.01 ㎛ to about 10 ㎛, but may not be limited thereto. For example, the pore size of the porous polymer substrate is about 0.01 μm to about 10 μm, about 0.01 μm to about 5 μm, about 0.01 μm to about 1 μm, about 1 μm to about 10 μm, about 1 μm to about 5 Μm, or about 5 μm to about 10 μm, but may not be limited thereto.

In one embodiment of the present application, the inorganic precursor is not particularly limited as long as it can be converted into an inorganic oxide by energy irradiation, for example, 3-aminopropyltriethoxysilane (3-aminopropyltriethoxysilane), polydimethylsiloxane (polydimethylsiloxane), SiCl ₄ (silicon tetrachloride), TEMASi (tetrakis-ethyl-methyl-amino-silcon), TiCl ₄ (titanium tetrachloride), TTIP (titanium-tetrakis-isoproproxide), TEMAT (tretrakis-ethyl-methyl-amino-titanium), TDMAT (tetrakis-dimethyl-amino-titanium), TDEAT (tetrakis-diethyl-amino-titanium), TMA (tri-methyl-aluminum), MPTMA (methyl-pyrrolidine-tri-methyl-aluminum), EPPTEA (ethyl-pyridine-triethyl) -aluminum), EPPDMAH (ethyl-pyridine-dimethyl-aluminum hydridge), IPA [(C ₃ H ₇ -O) ₃ Al], TEMAH (tetrakis-ethyl-methyl-amino-hafnium), TEMAZ (tetrakis-ethyl-methyl -amido-zirconium), tetrakis-dimethyl-amino-hafnium (TDMAH), tetrakis-dimethyl-amino-zirconium (TDMAZ), tetrakis-diethyl-amino-hafnium (TDEAH), tetrakis-diethyl-amino-zirconium (TDEAZ), Hafnium tetra-tert-butoxide (HTB), zirconium tetra-tert-butoxide (ZTB), hafnium tetrachloride (HfCl ₄ ), Ba (C ₅ H ₇ O ₂ ) ₂ , Sr (C ₅ H ₇ O ₂ ) ₂ , Ba (C ₁₁ H ₁₉ O ₂ ) ₂ , Sr (C ₁₁ H ₁₉ O ₂ ) ₂ , Ba (C ₅ HF ₆ O ₂ ) ₂ , Sr (C ₁₀ H ₁₀ F ₇ O ₂ ) ₂ , Ba (C ₁₀ H ₁₀ F ₇ O ₂ ) ₂ Sr (C ₁₀ H ₁₀ F ₇ O ₂ ) ₂ , Ba (C ₁₁ H ₁₉ O ₂ ) -CH ₃ (OCH ₂ CH ₂ ) ₄ OCH ₃ , Sr (C ₁₁ H ₁₉ O ₂ ) ₂ -CH ₃ (OCH ₂ HC ₂ ) ₄ OCH ₃ , Ti (OC ₂ H ₅ ) ₄ , Ti (OC ₃ H ₇ ) ₄ , Ti (OC ₄ H ₉ ) ₄ , Ti (C ₁₁ H ₁₉ O ₂ ) ₂ (OC ₃ H ₇ ) ₂ , Ti (C ₁₁ H ₁₉ O ₂ ) ₂ [O (CH ₂ ) ₂ OCH ₃ ] ₂ , Pb (C ₅ H ₇ O ₂ ) ₂ , Pb (C ₅ HF ₆ O ₂ ) ₂ , Pb (C ₅ H ₄ F ₃ O ₂ ) ₂ , Pb (C ₁₁ H ₁₉ O ₂ ) ₂ , Pb (C ₂ H ₅ ) ₄ , La (C ₅ H ₇ O ₂ ) ₃ , La (C ₅ HF ₆ O ₂ ) ₃ , La (C ₅ H ₄ F ₃ O ₂ ) ₃ , La (C ₁₁ H ₁₉ O ₂ ) ₃ , Zr (OC ₄ H ₉ ) ₄ , Zr (C ₅ HF ₆ O ₂ ) ₄ , Zr (C ₅ H ₄ F ₃ O ₂ ) ₄ , Zr (C ₁₁ H ₁₉ O ₂ ) ₄ , Zr (C ₁₁ H ₁₉ O ₂ ) ₂ (OCH ₃ H ₇ ) ₂ , TMSTEMAT [MeSiN = Ta (NEtMe) ₃ ], TBITEMAT [Me ₃ CN = Ta (NEtME) ₃ ], TBTDET [Me ₃ CN = Ta (Net ₂ ) ₃ ], PEMAT (Ta [N (CH ₃ ) (C ₂ H ₅ )] ₅ ), PDEAT (Ta [N (C ₂ H ₅ ) ₂ ] ₅ ), PDMAT (Ta [N (CH ₃ ) ₂ ] ₅ ), TaF ₅ , and combinations thereof, but may not be limited thereto.

In one embodiment of the present invention, the thickness of the inorganic oxide thin film formed on the outer surface and the surface of the inner pores of the porous polymer substrate is about 1/2 of the size of the pores included in the porous polymer substrate (about 1/2 Up to a thickness). For example, the thickness of the inorganic oxide thin film is less than about 5 μm, less than about 4 μm, less than about 3 μm, less than about 2 μm, less than about 1 μm, less than about 900 nm, less than about 800 nm, less than about 700 nm. Coating as a thickness of less than about 600 nm, less than about 500 nm, less than about 400 nm, less than about 300 nm, less than about 200 nm, less than about 100 nm, less than about 50 nm, less than about 10 nm, or less than about 5 nm. It may be, but may not be limited thereto. The thickness of the inorganic oxide thin film may be about 1 nm or more, and when the thickness is less than about 1 nm, there is a concern that the thermal characteristics of the separator at high temperature may not be maintained.

Inorganic oxide thin film according to the present invention, the inorganic oxide is adsorbed on the porous polymer substrate to be applied using a solution process using a chemical reaction mechanism of the inorganic compound and the inorganic oxide through the decomposition process of the inorganic precursor generated by chemical crosslinking It is formed on the porous polymer substrate as a thin film. The inorganic precursors may be present in liquid or solid phase at room temperature, and these inorganic precursors may be used as liquid or solid phases according to economic or process requirements as inorganic compounds of high purity.

The inorganic oxide thin film according to the present application may include particles of the inorganic oxide, but may not be limited thereto.

In one embodiment of the present application, the metal oxide thin film formed by the atomic layer deposition method, Al ₂ O ₃ , ZrO ₂ , TiO ₂ , SnO ₂ , CeO ₂ , ZnO, MgO, CaO, SrO, BaO, Na ₂ O, B ₂ O ₃ , Mn ₂ O ₃ , Y ₂ O ₃ , WO ₃ , and may be to include those selected from the group consisting of, but may not be limited thereto. The metal oxide may serve as passivation by forming the metal oxide thin film on the porous polymer substrate on which the inorganic oxide thin film is formed by atomic layer deposition, but may not be limited thereto.

In one embodiment of the present application, the precursor used to form the metal oxide thin film by the atomic layer deposition method, TMA (tri-methyl-aluminum), MPTMA (methyl-pyrrolidine-tri-methyl-aluminum), EPPTEA ( ethyl-pyridine-triethyl-aluminum), EPPDMAH (ethyl-pyridine-dimethyl-aluminum hydridge), IPA [(C ₃ H ₇ -O) ₃ Al], TiCl ₄ (titanium tetrachloride), TTIP (titanium-tetrakis-isoproproxide) , TEMAT (tretrakis-ethyl-methyl-amino-titanium), TDMAT (tetrakis-dimethyl-amino-titanium), TDEAT (tetrakis-diethyl-amino-titanium), TEMAH (tetrakis-ethyl-methyl-amino-hafnium), TEMAZ (Tetrakis-ethyl-methyl-amido-zirconium), TDMAH (tetrakis-dimethyl-amino-hafnium), TDMAZ (tetrakis-dimethyl-amino-zirconium), TDEAH (tetrakis-diethyl-amino-hafnium), TDEAZ (tetrakis-diethyl -amino-zirconium), HTB (hafnium tetra-tert-butoxide), ZTB (zirconium tetra-tert-butoxide), HfCl ₄ (hafnium tetrachloride), Ba (C ₅ H ₇ O ₂ ) ₂ , Sr (C ₅ H ₇ O ₂ ) ₂ , Ba (C ₁₁ H ₁₉ O ₂ ) ₂ , Sr (C ₁₁ H ₁₉ O ₂ ) ₂ , Ba (C ₅ HF ₆ O ₂ ) ₂ , Sr (C ₁₀ H ₁₀ F ₇ O ₂ ) ₂ , Ba (C ₁₀ H ₁₀ F ₇ O ₂ ) ₂ Sr (C ₁₀ H ₁₀ F ₇ O ₂ ) ₂ , Ba (C ₁₁ H ₁₉ O ₂ ) -CH ₃ (OCH ₂ CH ₂ ) ₄ OCH ₃ , Sr (C ₁₁ H ₁₉ O ₂ ) ₂ -CH ₃ (OCH ₂ HC ₂ ) ₄ OCH ₃ , Ti (OC ₂ H ₅ ) ₄ , Ti (OC ₃ H ₇ ) ₄ , Ti (OC ₄ H ₉ ) ₄ , Ti (C ₁₁ H ₁₉ O ₂ ) ₂ (OC ₃ H ₇ ) ₂ , Ti (C ₁₁ H ₁₉ O ₂ ) ₂ [O (CH ₂ ) ₂ OCH ₃ ] ₂ , Pb (C ₅ H ₇ O ₂ ) ₂ , Pb (C ₅ HF ₆ O ₂ ) ₂ , Pb (C ₅ H ₄ F ₃ O ₂ ) ₂ , Pb (C ₁₁ H ₁₉ O ₂ ) ₂ , Pb (C ₂ H ₅ ) ₄ , La (C ₅ H ₇ O ₂ ) ₃ , La (C ₅ HF ₆ O ₂ ) ₃ , La (C ₅ H ₄ F ₃ O ₂ ) ₃ , La (C ₁₁ H ₁₉ O ₂ ) ₃ , Zr (OC ₄ H ₉ ) ₄ , Zr (C ₅ HF ₆ O ₂ ) ₄ , Zr (C ₅ H ₄ F ₃ O ₂ ) ₄ , Zr (C ₁₁ H ₁₉ O ₂ ) ₄ , Zr (C ₁₁ H ₁₉ O ₂ ) ₂ (OCH ₃ H ₇ ) ₂ , TMSTEMAT [MeSiN = Ta (NEtMe) ₃ ], TBITEMAT [Me ₃ CN = Ta (NEtMe) ₃ ], TBTDET [Me ₃ CN = Ta (Net ₂ ) ₃ ], PEMAT [Ta ((CH ₃ ) (C ₂ H ₅ )) ₅ ], PDEAT [Ta (N (C ₂ H ₅ ) ₂ ) ₅ ], PDMAT [Ta (N (CH ₃ ) ₂ ) ₅ ], TaF ₅ , and combinations thereof, but may not be limited thereto.

In one embodiment of the present application, the atomic layer deposition method may be performed in a temperature range of about 60 ℃ to about 200 ℃, but may not be limited thereto. For example, the atomic layer deposition method may be about 60 ° C. to about 200 ° C., about 60 ° C. to about 190 ° C., about 60 ° C. to about 180 ° C., about 60 ° C. to about 170 ° C., about 60 ° C. to about 160 ° C., about 60 ° C to about 150 ° C, about 60 ° C to about 140 ° C, about 60 ° C to about 130 ° C, about 60 ° C to about 120 ° C, about 60 ° C to about 110 ° C, about 60 ° C to about 100 ° C, about 60 ° C To about 90 ° C, about 60 ° C to about 80 ° C, about 60 ° C to about 70 ° C, about 70 ° C to about 200 ° C, about 70 ° C to about 190 ° C, about 70 ° C to about 180 ° C, about 70 ° C to about 170 ° C, about 70 ° C to about 160 ° C, about 70 ° C to about 150 ° C, about 70 ° C to about 140 ° C, about 70 ° C to about 130 ° C, about 70 ° C to about 120 ° C, about 70 ° C to about 110 ° C , About 70 ° C. to about 100 ° C., about 70 ° C. to about 90 ° C., about 70 ° C. to about 80 ° C., about 80 ° C. to about 200 ° C., about 80 ° C. to about 190 ° C., about 80 ° C. to about 180 ° C., about 80 ° C to about 170 ° C, about 80 ° C to about 160 ° C, about 80 ° C to about 150 ° C, about 80 ° C to about 140 ° C, about 80 ° C to about 130 ° C, about 80 ° C to about 120 ° C, about 80 ° C to about 110 ° C, about 80 ° C to about 100 ° C, about 80 ° C to about 90 ° C, about 90 ° C To about 200 ° C, about 90 ° C to about 190 ° C, about 90 ° C to about 180 ° C, about 90 ° C to about 170 ° C, about 90 ° C to about 160 ° C, about 90 ° C to about 150 ° C, about 90 ° C to about 140 ° C, about 90 ° C to about 130 ° C, about 90 ° C to about 120 ° C, about 90 ° C to about 110 ° C, about 90 ° C to about 100 ° C, about 100 ° C to about 200 ° C, about 100 ° C to about 190 ° C , About 100 ° C. to about 180 ° C., about 100 ° C. to about 170 ° C., about 100 ° C. to about 160 ° C., about 100 ° C. to about 150 ° C., about 100 ° C. to about 140 ° C., about 100 ° C. to about 130 ° C., about 100 ° C to about 120 ° C, about 100 ° C to about 110 ° C, about 110 ° C to about 200 ° C, about 110 ° C to about 190 ° C, about 110 ° C to about 180 ° C, about 110 ° C to about 170 ° C, about 110 ° C To about 160 ° C., about 110 ° C. to about 150 ° C., about 110 ° C. to about 140 ° C., 110 ° C to about 130 ° C, about 110 ° C to about 120 ° C, about 120 ° C to about 200 ° C, about 120 ° C to about 190 ° C, about 120 ° C to about 180 ° C, about 120 ° C to about 170 ° C, and about 120 ° C To about 160 ° C., about 120 ° C. to about 150 ° C., about 120 ° C. to about 140 ° C., about 120 ° C. to about 130 ° C., about 130 ° C. to about 200 ° C., about 130 ° C. to about 190 ° C., about 130 ° C. to about 180 ° C, about 130 ° C to about 170 ° C, about 130 ° C to about 160 ° C, about 130 ° C to about 150 ° C, about 130 ° C to about 140 ° C, about 140 ° C to about 200 ° C, about 140 ° C to about 190 ° C , About 140 ° C. to about 180 ° C., about 140 ° C. to about 170 ° C., about 140 ° C. to about 160 ° C., about 140 ° C. to about 150 ° C., about 150 ° C. to about 200 ° C., about 150 ° C. to about 190 ° C., about 150 ° C to about 180 ° C, about 150 ° C to about 170 ° C, about 150 ° C to about 160 ° C, about 160 ° C to about 200 ° C, about 160 ° C to about 190 ° C, about 160 ° C to about 180 ° C, about 160 ° C To about 170 ° C, about 170 ° C to about 200 ° C, about 170 ° C To about 190 ° C, about 170 ° C to about 180 ° C, about 180 ° C to about 200 ° C, about 180 ° C to about 190 ° C, or about 190 ° C to about 200 ° C, but is not limited thereto. You may not.

In one embodiment of the present application, the thickness of the metal oxide thin film may be about 100 nm or less, but may not be limited thereto. For example, about 100 nm or less, about 90 nm or less, about 80 nm or less, about 70 nm or less, about 60 nm or less, about 50 nm or less, about 40 nm or less, about 30 nm or less, about 20 nm or less, or It may be about 10 nm or less, but may not be limited thereto.

In the method of manufacturing an organic-inorganic composite porous separator according to the present invention, an inorganic oxide thin film is formed on the outer surface of the porous polymer substrate and the surface of the inner pores by a solution process using an inorganic precursor, thereby providing excellent mechanical properties and high lithium of the existing separator. High-capacity electrochemistry by increasing the volume of the limited electrode active material in the electrochemical device including the thin film separator to improve the thermal characteristics while maintaining the ion mobility, and to reduce the electrical resistance acting in the battery and to enable high-density charging The manufacture of the device can be enabled. In addition, by forming an inorganic oxide thin film to form a metal oxide thin film by using an ALD process in the thermally improved separator, the side reaction between the inorganic oxide thin film and the electrolyte can be suppressed to improve the quality of the separator.

A second aspect of the present application is prepared by the method according to the first aspect of the present application;

It provides an organic-inorganic composite porous separator comprising an inorganic oxide thin film formed on the outer surface and the surface of the inner pores of the porous polymer substrate and a metal oxide thin film formed on the inorganic oxide thin film.

In the organic-inorganic composite porous membrane according to the present invention, an inorganic oxide thin film is formed on the outer surface of the porous polymer substrate and the surface of the inner pores by a solution process using an inorganic precursor, thereby providing excellent mechanical properties and high lithium ion mobility of the existing separator. Fabrication of high-capacity electrochemical devices by improving the thermal properties, maintaining the electrical properties while reducing the electrical resistance in the battery, and making thin-walled separators capable of high density charging and increasing the volume of the limited electrode active material in the electrochemical devices having the same Can be enabled. In addition, by forming an inorganic oxide thin film to form a metal oxide thin film by using an ALD process in the thermally improved separator, the side reaction between the inorganic oxide thin film and the electrolyte can be suppressed to improve the quality of the separator.

As for the organic-inorganic composite porous separator according to the second aspect of the present application, all the contents described for the first aspect of the present application are applied, and duplicate descriptions are omitted.

In one embodiment of the present application, the organic-inorganic composite porous separator may be for an electrochemical device, but may not be limited thereto.

A third aspect of the present application provides an electrochemical device including an organic-inorganic composite porous separator, a positive electrode, a negative electrode, and an electrolyte according to the second aspect of the present application. For the organic-inorganic composite porous separator according to this aspect, all of the contents described with respect to the first aspect of the present application may be applied.

In one embodiment of the present application, the electrochemical device may be to include a lithium secondary battery, but may not be limited thereto.

The electrochemical device includes all devices that undergo an electrochemical reaction, and specifically, all kinds of primary cells, secondary cells, fuel cells, solar cells, or capacitors. In particular, the electrochemical device may be a lithium secondary battery of a secondary battery, specific examples thereof include a lithium metal secondary battery, a lithium ion secondary battery, a lithium polymer secondary battery, or a lithium ion polymer secondary battery, but is not limited thereto. It doesn't work.

The electrochemical device may be manufactured according to a conventional method known in the art, for example, the electrochemical device is manufactured by injecting an electrolyte after assembling through the positive electrode and the separator described above.

The electrode is not particularly limited, but the positive electrode active material may be a conventional positive electrode active material that may be used for the positive electrode of a conventional electrochemical device, and in particular, lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, or combinations thereof. Lithium adsorption material and the like can be used, such as a composite oxide formed by.

In addition, the negative electrode active material may be a conventional negative electrode active material that can be used for the negative electrode of the conventional electrochemical device, in particular lithium adsorption, such as lithium metal or lithium alloy and carbon, petroleum coke, activated carbon, graphite, or other carbons Materials and the like can be used. The above-mentioned positive electrode active material may be made of a positive electrode current collector, i.e., a foil and a negative electrode current collector, i.e., copper, gold, nickel, a copper alloy, and combinations thereof, respectively, produced by aluminum, nickel or combinations thereof. The positive electrode is constituted in a form bound to the foil produced by the method.

The electrolyte that may be used herein, A ⁺ B ^- A salt of the structure, such as, A ⁺ comprises an alkaline metal cation or a cation consisting of a combination thereof, such as Li ^+, Na ^+, and K ^+, B ^- is _{^{_{^{PF 6 -, BF 4 -,}}}} Cl -, Br -, I-, ClO 4 -, AsF 6 -, CH 3 CO 2 -, CF 3 SO 3 -, N (CF 3 SO 2) 2 -, and C Salts containing ions consisting of anions such as (CF ₂ SO ₂ ) ₃ ^- or combinations thereof include propylene carbonate (PC), ethylene carbonate (EC) and diethyl carbonate (DEC). ), Dimethyl carbonate (DMC), dipropyl carbonate (DPC), dimethylsulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, tetrahydro Tetrahydrofuran, N-methyl-2-pyrrolidone (NMP), ethylmethylcarbonei (Ethylmethyl carbonate, EMC), gamma-butyrolactone (gamma-butyrolactone, GBL) or in an organic solvent consisting of a combination thereof, but may be dissolved or dissociated, may not be limited thereto.

The electrolyte injection may be performed at an appropriate step in the battery manufacturing process, depending on the manufacturing process and the required physical properties of the final product. That is, the battery assembly may be performed before the battery assembly or at the final stage of battery assembly.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the following Examples are only provided to help understanding of the present application, and the contents of the present application are not limited to the following Examples.

[[ 실시예Example 1: 유기-무기 복합 다공성 분리막의 제조] 1: Preparation of Organic-Inorganic Composite Porous Membrane]

Melt extrusion of the polyethylene (PE) polymer, melt extrusion of the crystalline polymer material to prepare a flow-forming separator, and then prepared a porous polymer substrate having a thickness of about 18 ㎛ by low-temperature stretching through crystallization heat treatment. After the plasma treatment of the porous polymer substrate for several minutes, 0.5 wt% of 3-aminopropyltriethoxysilane, an inorganic precursor containing a small amount of Si groups, was first coated and distilled water After washing with nitrogen, dried with nitrogen and then coated with polydimethylsiloxane inorganic precursor for 2 hours and placed on a hot plate at 80 ° C for several hours. Then, it is washed with isopropyl alcohol, dried with nitrogen, and then decomposed with a compound generated from a chemical reaction mechanism occurring on the surface of the porous substrate by ozone treatment using an ultraviolet / ozone device. Inorganic Oxide SiO₂ Was coated on the outer and inner pore surfaces of the porous polymeric substrate as thin films. The SiO₂ The thickness of the thin film was adjusted to be about 20 nm. Then trimethylaluminum, an alkyl-based compound [TMA; Al (CH₃)₃,Aldrich Al₂O₃ Decomposition of the TMA using atomic layer deposition (ALD) at a temperature of 150 ℃ using a precursor of, the SiO₂ 10 nm thick Al in the polyethylene separator with thin film₂O₃ A thin film was deposited. As a result, SiO₂ And Al₂O₃A separator coated with a thickness of 20 nm and 10 nm, respectively, on the outer surface and the inner pore surface of the porous porous polymer substrate was obtained. A schematic process diagram of the method of manufacturing a separator according to the present embodiment is shown in FIG. 1, and a schematic diagram of the separator thus prepared is shown in FIG. 2.

[[ 실시예Example 2: 리튬 이차 전지의 제조] 2: Fabrication of Lithium Secondary Battery]

N-methyl-2 pyrrolidone (NMP), which is 92% by weight of lithium cobalt composite oxide as a positive electrode active material, 4% by weight of carbon black as a conductive material, and 4% by weight of polyvinylidene fluoride (PVdF) as a binder ) To prepare a positive electrode mixture slurry. The positive electrode active material slurry was applied to an aluminum (Al) thin film of a positive electrode contactor having a thickness of 20 μm and dried to prepare a positive electrode, and then roll-pressed.

A negative electrode mixture slurry was prepared by adding carbon powder as a negative electrode active material, PVdF as a binder, and carbon black as a conductive agent at 96 wt%, 3 wt%, and 1 wt%, respectively, to NMP as a solvent. The negative electrode active material slurry was applied to a copper (Cu) thin film, which is a negative electrode current collector having a thickness of 10 μm, and dried to prepare a negative electrode, and then roll-pressed.

The prepared positive electrode, the negative electrode, and the separator according to Example 1 were assembled using a stacking method, and the assembled battery was an electrolyte solution [ethylene carbonate (EC) / ethyl methyl carbonate (EMC) / diethylene carbonate (DEC). ) = 1/1/1 (volume ratio), and 1 mol of lithium hexaproprophosphate (LiPF6)] were injected to prepare a lithium secondary battery.

[[ 비교예Comparative example 1] One]

A battery was manufactured in the same manner as in Example 2, except that an inorganic oxide thin film (SiO ₂ ) and a metal oxide thin film (Al ₂ O ₃ ) were used.

[[ 비교예Comparative example 2] 2]

A battery was manufactured in the same manner as in Example 2, except that the Al ₂ O ₃ metal oxide thin film was not coated and a separator made of a PE porous substrate coated with only a SiO ₂ thin film was used.

[실험예 1: 분리막 표면의 분석]Experimental Example 1 Analysis of the Membrane Surface

Pure porous polymer membrane (PE, Figure 3a), SiO ₂ by the solution process on the polymer substrate Scan the surface of the separator [PE / SiO ₂ (20nm), FIG. 3b] formed with a thin film, and the separator [PE / SiO ₂ (20nm) / Al ₂ O ₃ (10nm), FIG. 3c] prepared according to Example 1 Observations were made using an electron microscope (Field Emission Scanning Electron Microscope; HITACHI Model, S-2700, Japan). As shown in FIG. 3c, it can be seen that the pores of the separator are well maintained even after formation of the SiO ₂ (20 nm, solution process) thin film and the Al ₂ O ₃ (10 nm, ALD) thin film.

[[ 실험예Experimental Example 2: 분리막의 열 2: column of separator 수축율Shrinkage 평가] evaluation]

To evaluate the heat shrinkage rate of the separator used in Example 1, Comparative Example 1, and Comparative Example 2, the results after storage for 30 minutes at 160 ℃ is shown in Table 1 below. The thermal shrinkage analysis was performed using a vacuum drying oven (MEMMERT, Germany).

[표 1]TABLE 1

Separation membrane which forms SiO ₂ inorganic oxide thin film by using solution process on PE porous substrate is also effective, but SiO ₂ inorganic oxide thin film (using solution process) and Al ₂ O ₃ metal oxide thin film (using ALD) on PE porous substrate When both are formed, it can be seen that the heat shrinkage rate is lower.

[실험예 3: 분리막의 기계적 물성 평가]Experimental Example 3: Evaluation of Mechanical Properties of Membrane

Tensile strength of the separator used in Example 1, Comparative Example 1, and Comparative Example 2 was evaluated and shown in Table 2 below. The tensile strength was measured using a tensile strength tester (UTM universal tester, ZWICK ROELL BZ005 / TH2S UTM).

[표 2]TABLE 2

Separation membrane which forms SiO ₂ inorganic oxide thin film by using solution process on PE porous substrate is also effective, but SiO ₂ inorganic oxide thin film (using solution process) and Al ₂ O ₃ metal oxide thin film (using ALD) on PE porous substrate When both are formed, it can be seen that mechanical properties are more excellent.

[실험예 4: 전지 성능 평가]Experimental Example 4: Battery Performance Evaluation

The batteries of Example 2, Comparative Example 1, and Comparative Example 2 were measured using a capacity measuring device (WONATECH, Korea) after the 3 C charge 0.2 C discharge capacity, the results are shown in Table 3 below.

[표 3]TABLE 3

Referring to Table 3, it can be confirmed that the battery of Example 2 according to the present application has an increased discharge capacity than the batteries of Comparative Example 1 and Comparative Example 2.

Although a cell using a PE porous separator (Comparative Example 1) or a separator (Comparative Example 2) including an SiO ₂ inorganic oxide thin film formed by using a solution process on a PE porous substrate is effective, PE porous as in Example 2 of the present application is effective. In the case of a battery using a separator in which both an SiO ₂ inorganic oxide thin film (solution step) and an Al ₂ O ₃ metal oxide thin film (ALD) were formed on a substrate, it was confirmed that the battery performance was more excellent.

The above description of the present application is intended for illustration, and it will be understood by those skilled in the art that the present invention may be easily modified in other specific forms without changing the technical spirit or essential features of the present application. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present application is indicated by the following claims rather than the above description, and it should be construed that all changes or modifications derived from the meaning and scope of the claims and their equivalents are included in the scope of the present application. .

Claims

Coating the inorganic precursor onto the porous polymeric substrate using a solution process;

Converting the coated inorganic precursor into an inorganic oxide by energy irradiation to form a porous polymer substrate having an inorganic oxide thin film formed thereon; And,

Forming a metal oxide thin film on an inorganic oxide thin film formed on the porous polymer substrate by using atomic layer deposition (ALD)

Including,

Method for producing an organic-inorganic composite porous separator.
The method of claim 1,

Before coating the inorganic precursor, further comprising the step of plasma treating the porous polymer substrate, a method for producing an organic-inorganic composite porous separator.
The method of claim 1,

The energy irradiation comprises irradiating heat, plasma, ultraviolet light, or laser, the organic-inorganic composite porous separator manufacturing method.
The method of claim 1,

The inorganic precursor is coated on the outer surface and the surface of the inner pores of the porous polymer substrate, a method for producing an organic-inorganic composite porous separator.
The method of claim 1,

The porous polymer substrate has a porosity of 5% to 95%, a method for producing an organic-inorganic composite porous separator.
The method of claim 1,

The coating of the inorganic precursor on the porous polymer substrate using the solution process includes coating the first inorganic precursor on the porous polymer substrate through a solution process, followed by heat treatment and further coating the second inorganic precursor. , Organic-inorganic composite porous membrane production method.
The method of claim 1,

The porous polymer substrate, polyethylene, high density polyethylene, low density polyethylene, linear low density polyethylene, high molecular weight polyethylene, polypropylene terephthalate, polyethylene terephthalate, polybutylene terephthalate, polyester, polyacetal, polyamide, polycarbonate, poly Mead, polyether ether ketone, polyether sulfone, polyphenylene oxide, polyphenylene sulfide, polyethylene naphthalene, and a combination thereof, the method of producing an organic-inorganic composite porous membrane .
The method of claim 1,

The inorganic oxide is an inorganic oxide having a dielectric constant of 5 or more, an inorganic oxide having a lithium ion transfer capacity, and a combination thereof, and a combination thereof, a method for producing an organic-inorganic composite porous separator.
The method of claim 8,

The inorganic oxide having a dielectric constant of 5 or more is SiO 2 , BaTiO 3 , Pb (Zr, Ti) O 3 (PZT), hafnia (HfO 2 ), SrTiO 3 , CeO 2 , MgO, NiO, CaO, ZnO, ZrO 2 , Y 2 O 3 , Al 2 O 3 , TiO 2 , SiC, and combinations thereof comprising one selected from the group consisting of, an organic-inorganic composite porous separator.
The method of claim 1,

The thickness of the inorganic oxide thin film is less than 5 ㎛, a method for producing an organic-inorganic composite porous separator.
The method of claim 1,

The thickness of the porous polymer substrate is 1 ㎛ to 100 ㎛, a method for producing an organic-inorganic composite porous separator.
The method of claim 1,

The pore size of the porous polymer substrate is 0.01 ㎛ to 10 ㎛, a method for producing an organic-inorganic composite porous separator.
The method of claim 1,

The metal oxide is Al 2 O 3 , ZrO 2 , TiO 2 , SnO 2 , CeO 2 , ZnO, MgO, CaO, SrO, BaO, Na 2 O, B 2 O 3 , Mn 2 O 3 , Y 2 O 3 , WO 3 , and combinations thereof, wherein the organic-inorganic composite porous separator is prepared.
The method of claim 1,

The atomic layer deposition method is carried out at a temperature range of 60 ℃ to 200 ℃, the organic-inorganic composite porous separator manufacturing method.
The method of claim 1,

The thickness of the metal oxide thin film is 100 nm or less, a method for producing an organic-inorganic composite porous separator.
Made by the method according to any one of claims 1 to 15,

An inorganic oxide thin film formed on the outer surface of the porous polymer substrate and the surface of the inner pores; And,

Metal oxide thin film formed on the inorganic oxide thin film

Including, an organic-inorganic composite porous separator.
The method of claim 16,

The organic-inorganic composite porous separator is for an electrochemical device, organic-inorganic composite porous separator.
An organic-inorganic composite porous separator according to claim 16, comprising an anode, a cathode, and an electrolyte, an electrochemical device.
The method of claim 18,

The electrochemical device is to include a lithium secondary battery, electrochemical device.