KR20180020423A - Composite gel polymer electrolyte membrane, method of manufacturing the same, lithium ion polymer battery having the same, and lithium air battery having the same - Google Patents

Abstract

The present invention is to provide a composite gel polymer electrolyte membrane having high ion conductivity, high hardness, stable interface and excellent electrochemical performance and inhibiting growth of lithium dendrite. The composite gel polymer electrolyte membrane of the present invention comprises: a polymer substrate; and a core-shell structure dispersed in the polymer substrate and consisting of a core unit having ion conductivity inside and a shell unit covering the surface of the core material.

Description

TECHNICAL FIELD The present invention relates to a composite gel polymer electrolyte membrane, a method of manufacturing the same, a lithium ion polymer battery including the same, and a lithium air cell including the same. the same}

TECHNICAL FIELD The present invention relates to a secondary cell, a composite gel polymer electrolyte membrane, a method for producing the same, a lithium ion polymer battery including the same, and a lithium air battery including the same.

The present invention refers to the research project of the serial number 2015R1DIA3A01019399 of the Basic Science Research Project supported by the Korea National Research Foundation.

The lithium metal has a high theoretical specific capacity of about 3860 mAh g ^{- 1} , a low density of about 0.59 g cm ^{- 3} , and a low electrode potential of about -3.04 V for a standard hydrogen electrode , Which is known as an anode material of a secondary battery. In addition, improved lithium ion batteries (LIBs) having higher energy densities such as lithium metal-based batteries (LMBs), lithium-air batteries, and lithium sulfur Lithium-sulfur batteries, etc., lithium metal is likely to continue to be used as an anode material. Despite the advantages of lithium, lithium metal anodes are no longer being improved in commercial secondary batteries because of the low charge-discharge cycle stability and low battery safety. The reason for this problem is that the growth of the lithium resin phase is difficult to control, and the coulombic efficiency during charging and discharging is low, and thus the use of lithium secondary batteries is limited.

In an open cell such as a lithium air cell, in order to prevent the contamination of the lithium metal electrodes and to improve the electrochemical performance of the lithium metal battery, various methods such as adding an additive to the electrolyte or forming a solid electrolyte lithium protective film Are proposed. Among them, the method of forming the solid electrolyte lithium protective film is more semi-permanent than the method of adding additives, has an excellent effect, and has an advantage of increasing lithium stability.

One of these improvement methods is to improve liquid electrolytes, for example by optimizing the type and content of solvents, salts, and additives to form thin, uniformly protective solid electrolyte interphase (SEI) layers . With the formation of the interlayer, the growth of the lithium resin particles can be effectively suppressed. However, the stability associated with the activated lithium metal in the damaged cell can still be a problem. Further, in the case of lithium air cells, since the cathode is open to the environment, the lithium metal may be deteriorated by moisture or contaminants diffusing from the outside.

Another improvement is the formation of solid electrolyte membranes, which can protect the lithium metal from oxygen, moisture and other gaseous impurities and inhibit lithium-based positive growth. At present, the main solid electrolyte is divided into a solid polymer electrolyte (SPE) and a solid ceramic electrolyte (SCE), and many electrolytes having different chemical compositions and structures are being studied. However, such organic solid-state polymer electrolytes and inorganic solid-state ceramic electrolytes have limitations.

The solid polymer electrolyte is advantageous in that it is easy to manufacture and has high flexibility and provides excellent ease of deformation, but has a disadvantage that it has insufficient hardness for inhibiting the growth of the lithium resin phase. On the other hand, the solid-phase ceramic electrolyte has an advantage that it has sufficient hardness to suppress the growth of the lithium resin phase, but it has a drawback that the workability is poor. Also, at the state of the art, these solid electrolytes have a number of different problems, for example, that they do not provide sufficient lithium ion conductivity at room temperature, or that the lithium metal contacts the reaction product during the charge- May occur. As a result, there is a need for new solid electrolyte materials having high ionic conductivity, high hardness, stable interface and good electrochemical performance.

The technical problem to be solved by the technical idea of the present invention is to provide a composite gel polymer electrolyte membrane which has high ion conductivity, high hardness, stable interface and excellent electrochemical performance, and in particular, inhibits lithium resin phase positive growth.

SUMMARY OF THE INVENTION The present invention is directed to a method for producing the composite gel polymer electrolyte membrane.

The present invention also provides a lithium ion polymer battery comprising the composite gel polymer electrolyte membrane.

The present invention also provides a lithium air cell including the composite gel polymer electrolyte membrane.

However, these problems are illustrative, and the technical idea of the present invention is not limited thereto.

According to an aspect of the present invention, there is provided a composite gel polymer electrolyte membrane comprising: a polymer substrate; And a core-shell structure consisting of a core part dispersed in the polymer substrate and having ion conductivity therein, and a shell part covering a surface of the core material; .

In some embodiments of the present invention, the polymer substrate is at least one of polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polyvinylidene fluoride (PVDF), and polymethyl methacrylate One can be included.

In some embodiments of the present invention, the core portion may have a perovskite structure.

In some embodiments of the present invention, the core portion may include aluminum-doped lithium lanthanum titanate (A-LLTO), lithium aluminum germanium phosphate (LAGP), and lithium And lithium aluminum titanium phosphate (LATP).

In some embodiments of the present invention, the core portion comprises (Li _0.33 La _0.56 ) _1.005 Ti _0.99 Al _0.01 O ₃ , and Li _{1 . 5} Al _{0 . 5 Ge 1 .5 (PO 4)} 3, Li 1. ₅ Al _{0 . 5} Ti _{1 .5} (PO ₄₎ may include at least any one of the _three.

In some embodiments of the present invention, the shell portion may comprise an amorphous phase.

In some embodiments of the present invention, the shell portion may include at least one of silicon oxide, silicon nitride, silicon oxynitride, zirconium oxide, zirconium nitride, zirconium oxynitride, and aluminum oxide.

In some embodiments of the present invention, m-SiO ₂ said shell portion having an oxygen atom to provide a binding site . ≪ / RTI >

In some embodiments of the present invention, the m-SiO ₂ Can be controlled using 3-glycidoxypropyl trimethoxysilane (GPTMS).

In some embodiments of the present invention, at least one of a hydroxyl group (OH < ^- & gt ^; ) and an epoxy group may be formed in the shell portion.

In some embodiments of the present invention, the core-shell structure may have a size ranging from 0.5 [mu] m to 3 [mu] m.

In some embodiments of the present invention, the shell portion may have a thickness in the range of 1 nm to 10 nm.

In some embodiments of the present invention, the polymer substrate and the core-shell structure may have a mass ratio ranging from 8: 2 to 2: 8.

In some embodiments of the present invention, the core-shell structure may be uniformly distributed within the polymer substrate.

In some embodiments of the present invention, the core-shell structure is capable of inhibiting the growth of the resin anticipation of the lithium metal.

In some embodiments of the present invention, the composite gel polymer electrolyte membrane is activated using a liquid electrolyte in which LiPF ₆ is mixed in a solution of ethylene carbonate and ethyl methyl carbonate .

In some embodiments of the present invention, the composite gel polymer electrolyte membrane is prepared by mixing lithium bis (trifluoromethane sulfonyl) with lithium tetraethylene glycol dimethyl ether (TEGDME) imide, LiTFSI) as the electrolyte.

According to an aspect of the present invention, there is provided a method of manufacturing a composite gel polymer electrolyte membrane, comprising: preparing an aluminum-doped lithium lanthanum titanate (A-LLTO) powder; Mixing a solution of the aluminum-doped lithium lanthanum titanate in ethanol with a solution of polyvinylpyrrolidone in deionized water to form a first mixed solution; Separating the supernatant by centrifuging the first mixed solution to form a surfactant-stabilized A-LLTO; Mixing the supernatant stabilized A-LLTO with ethanol, deionized water, and ammonia water to form a suspension solution; Adding ethanol containing tetraisosilane to the suspension solution to form a second mixed solution; And centrifuging the second mixed solution to form A-LLTO / m-SiO ₂ particles.

According to an aspect of the present invention, there is provided a lithium ion polymer battery comprising: an anode; Cathode; And a polymer substrate interposed between the anode and the cathode; And a core-shell structure comprising a core portion dispersed in the polymer substrate and having an ion conductivity therein, and a shell portion covering the surface of the core material.

According to an aspect of the present invention, there is provided a lithium ion secondary battery comprising: an anode; Cathode; And a polymer substrate interposed between the anode and the cathode; And a core-shell structure comprising a core portion dispersed in the polymer substrate and having an ion conductivity therein, and a shell portion covering the surface of the core material.

The composite gel polymer electrolyte (CGPE) according to the technical concept of the present invention can be prepared by a simple solution casting method and can be produced by activating a liquid electrolyte. The composite gel polymer electrolyte is composed of PVDF-HFP substrate comprising a A-LLTO particles covered with the m-SiO ₂ layer.

The prepared composite gel polymer electrolyte has higher ionic conductivity, broad electrochemical stability range, and interface stability than a pure gel polymer electrolyte (GPE). Moreover, under high polarization conditions, the composite gel polymer electrolyte effectively inhibits the growth of lithium resin implants, because the hardness is increased as the inorganic A-LLTO / m-SiO ₂ is added. Accordingly, the lithium ion polymer and lithium air battery cells including the composite gel polymer electrolyte exhibit significantly improved cycle characteristics as compared with the prior art. Particularly, since the composite gel polymer electrolyte functions as the protective layer against the lithium metal electrode in the lithium air battery cell, it is possible to suppress the lithium resin assumptions and effectively prevent the contamination of the lithium electrode by oxygen gas or impurities diffused from the cathode .

Therefore, the composite gel polymer electrolyte according to the technical idea of the present invention can be applied to a lithium ion polymer battery and a lithium air battery.

The effects of the present invention described above are exemplarily described, and the scope of the present invention is not limited by these effects.

1 is a cross-sectional view of a lithium ion polymer battery according to an embodiment of the present invention.
2 is a cross-sectional view of a lithium ion battery according to an embodiment of the present invention.
3 is a graph showing an X-ray diffraction pattern of A-LLTO / m-SiO ₂ constituting a composite gel polymer electrolyte according to an embodiment of the present invention.
4 is a microstructure photograph of A-LLTO / m-SiO ₂ constituting a composite gel polymer electrolyte according to an embodiment of the present invention.
5 is a graph showing Fourier transform infrared spectroscopy analysis of A-LLTO / m-SiO ₂ constituting a composite gel polymer electrolyte according to an embodiment of the present invention.
6 is a schematic diagram of A-LLTO / m-SiO ₂ of a core-shell structure making up a composite gel polymer electrolyte according to one embodiment of the present invention.
7 is a photograph showing transparency of a composite gel polymer electrolyte according to an embodiment of the present invention.
8 is a graph showing changes in electrochemical characteristics depending on the mass ratio of A-LLTO / m-SiO ₂ and PVDF-HFP constituting the composite gel polymer electrolyte according to an embodiment of the present invention
9 is a graph showing the charge-discharge cycle stability depending on the mass ratio of A-LLTO / m-SiO ₂ and PVDF-HFP constituting the composite gel polymer electrolyte according to an embodiment of the present invention.
10 is a scanning electron micrograph of a composite gel polymer electrolyte membrane and a composite gel polymer electrolyte according to an embodiment of the present invention.
11 is a graph showing an X-ray diffraction pattern of a composite gel polymer electrolyte membrane according to an embodiment of the present invention.
12 is a graph showing electrochemical characteristics of A-LLTO / m-SiO ₂ constituting a composite gel polymer electrolyte according to an embodiment of the present invention.
13 is a graph showing a constant current cycle characteristic of a composite gel polymer electrolyte according to an embodiment of the present invention.
FIG. 14 is a graph showing electrochemical characteristics of a composite gel polymer electrolyte according to an embodiment of the present invention over time. FIG.
15 is optical micrographs showing microstructural changes over time of the composite gel polymer electrolyte according to one embodiment of the present invention.
16 is a graph showing an electrochemical stability range of a composite gel polymer electrolyte according to an embodiment of the present invention.
17 is a graph showing a change in capacitance of a lithium ion polymer battery cell including a composite gel polymer electrolyte according to an embodiment of the present invention in accordance with a charge-discharge cycle.
18 is a graph showing the coulomb efficiency and the cell cell potential according to the charge-discharge cycle of the lithium ion polymer battery cell including the composite gel polymer electrolyte according to an embodiment of the present invention.
19 is a graph illustrating electrochemical characteristics of a lithium ion polymer battery cell including a composite gel polymer electrolyte according to an embodiment of the present invention and a model therefor.
20 is a view illustrating a MnO ₂ Ni cathode used in a nickel air cell according to an embodiment of the present invention.
21 is a graph showing charge-discharge cycle characteristics of a lithium air cell including a composite gel polymer electrolyte according to an embodiment of the present invention.
22 is a scanning electron micrograph showing the microstructure of a lithium metal electrode included in a lithium air cell including a composite gel polymer electrolyte according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art. The scope of technical thought is not limited to the following examples. Rather, these embodiments are provided so that this disclosure will be more thorough and complete, and will fully convey the scope of the invention to those skilled in the art. The same reference numerals denote the same elements at all times. Further, various elements and regions in the drawings are schematically drawn. Accordingly, the technical spirit of the present invention is not limited by the relative size or spacing depicted in the accompanying drawings.

As used herein, the terms "gel polymer electrolyte membrane" and "composite gel polymer electrolyte membrane" refer to the electrolyte structure prior to activation by the liquid electrolyte, and "gel polymer electrolyte" and "composite gel polymer electrolyte" Will be referred to as the electrolyte structure after being activated by the electrolyte.

Abbreviations used throughout are defined as follows.

1. Composite gel polymer electrolyte is abbreviated as "CGPE".

2. Gel polymer electrolyte is abbreviated as "GPE".

3. Polyvinylidene fluoride-hexafluoropropylene is abbreviated as "PVDF-HFP".

4. Aluminum-doped lithium lanthanum titanate is abbreviated as "A-LLTO".

5. Modified SiO ₂ It is abbreviated as "m-SiO _2".

6. Dibutyl phthalate is abbreviated as "DBP".

7. Ethylene carbonate is abbreviated as "EC".

8. Ethyl methyl carbonate is abbreviated as "EMC".

9. Tetraethylene glycol dimethyl ether is abbreviated as "TEGDME ".

10. Lithium bis (trifluoromethane sulfonyl) imide is abbreviated as "LiTFSI ".

11. covered with MnO ₂ catalyst Nickel is abbreviated as "MnO ₂ @Ni".

1 is a cross-sectional view of a lithium ion polymer battery 100 according to an embodiment of the present invention.

Referring to FIG. 1, a lithium ion polymer battery 100 includes an anode 110, a cathode 120, and an electrolyte 130. The lithium ion polymer battery 100 may further include an anode current collector 150, a cathode current collector 160, a spring 180, and a body 190.

The anode 110 may include a material that becomes a cation when it loses electrons at the time of discharging, and may include, for example, a metal and may include, for example, lithium, zinc, magnesium, aluminum, and calcium.

The cathode 120 may include a material that stores the cation at the time of discharge, for example, an oxide, and may include, for example, LiCoO ₂ .

The electrolyte 130 is interposed between the anode 110 and the cathode 120 and may include an electrolytic material. The electrolyte 130 may comprise a composite gel polymer electrolyte (CGPE) according to the teachings of the present invention. The electrolyte 130 will be described in detail below.

The anode current collector 150 is an optional component positioned to contact the anode 110 at a location opposite the electrolyte 130 about the anode 110. The anode current collector 150 functions to collect current to the anode 110 and may include a material having excellent electrical conductivity and oxidation resistance and may include, for example, a metal, For example, stainless steel, aluminum, copper, carbon, and the like.

The cathode current collector 160 is an optional component positioned to contact the cathode 120 at a location opposite the electrolyte 130 about the cathode 120. The cathode current collector 160 functions to collect current to the cathode 120 and may include a material having excellent electrical conductivity and oxidation resistance and may include, for example, a metal, For example, stainless steel, aluminum, copper, carbon, and the like.

The spring 180 may be positioned on the anode 110 as an optional component and may function to squeeze the anode 110, the cathode 120, and the electrolyte 130, For example, stainless steel, aluminum, copper, and the like.

The body 190 may receive the anode 110, the cathode 120, the electrolyte 130, the anode current collector 150, the cathode current collector 160, and the spring 180. The body 190 may have various shapes, and may be formed as a CR-2032, for example, as shown in Fig. Further, the positions of the anode 110, the cathode 120, and the electrolyte 130 in the body 190 are illustrative and can be reversed.

2 is a cross-sectional view of a lithium ion battery 200 according to an embodiment of the present invention.

2, the lithium air battery 200 includes an anode 210, a cathode 220, an electrolyte 230, and a separator 240. The lithium air battery 200 may further include an anode current collector 250, a cathode current collector 260, a spring 280, and a body 290.

The anode 210 may include a material that becomes a cation by losing electrons upon discharge and may include, for example, a metal and may include, for example, lithium, zinc, magnesium, aluminum, and calcium.

Cathode 220, can comprise a material for storing the cation at the time of discharge, for example, may comprise an oxide, for example, it may include MnO ₂ @Ni.

The electrolyte 230 is interposed between the anode 210 and the cathode 220 and may include an electrolytic material. The electrolyte 230 may comprise a composite gel polymer electrolyte (CGPE) according to the teachings of the present invention. The electrolyte 230 will be described in detail below.

The separator 240 is interposed between the cathode 220 and the electrolyte 230 to prevent direct contact between the cathode 220 and the electrolyte 230 and thus protects the electrolyte 230 from the external environment. can do. Further, the separator 240 may contain a liquid electrolyte therein.

The anode current collector 250 is an optional component positioned to contact the anode 210 at a location opposite the electrolyte 230 about the anode 210. The anode current collector 250 functions to collect current to the anode 210 and may include a material having excellent electrical conductivity and oxidation resistance and may include, for example, a metal, For example, stainless steel, aluminum, copper, and the like.

The cathode current collector 260 is an optional component positioned to contact the cathode 220 at a location opposite the electrolyte 230 about the cathode 220. The cathode current collector 260 functions to collect current to the cathode 220 and may include a material having excellent electrical conductivity and oxidation resistance and may include, for example, a metal, For example, stainless steel, aluminum, copper, carbon, and the like.

The spring 280 can be positioned on the anode 210 as an optional component and can function to compress the anode 210, the cathode 220, the electrolyte 230 and the separator 240 For example, a metal, and may include, for example, stainless steel, aluminum, copper, and the like.

The body 290 is capable of receiving the anode 210, the cathode 220, the electrolyte 230, the separator 240, the anode current collector 250, the cathode current collector 260, have. The body 290 may have various shapes and may be formed as a CR-2032, for example, as shown in Fig. The positions of the anode 210, the cathode 220, the electrolyte 230, and the separator 240 in the body 290 are illustrative and can be reversed.

The main body 290 is formed with a plurality of holes 292 in the region adjacent to the cathode 220. Oxygen gas can be drawn through the hole 292. This hole 292 can be covered with an oxygen permeable membrane 270 that is permeable to oxygen, thereby preventing the evaporation of the electrolyte 230 from evaporating to the outside. The oxygen permeable membrane 270 may include, for example, polytetrafluoroethylene (PTFE) 270.

Hereinafter, the composite gel polymer electrolyte (CGPE) according to the technical idea of the present invention constituting the electrolytes 130 and 230 of FIGS. 1 and 2 will be described in detail.

Conventional solid polymer electrolyte are the most of low wettability with limited ionic conductivity ^- in spite of having a limit (10 ^-5 S cm ^-1 to 10 ^-6 S cm at room temperature is less than ^1), GPE is significantly based on a variety of polymer . Of these, GPEs based on copolymers of PVDF-HFP are of high interest because of their high ionic conductivity, stable interface properties, and excellent electrochemical performance. To improve the properties of GPEs, a method of inserting inorganic fillers into a polymer substrate has been proposed. However, high ion conductivity can be obtained only when the inorganic filler is inserted at a very low content, and the ion conductivity is drastically reduced when the content of the inorganic filler is increased. On the other hand, as the content of inorganic filler was increased, the hardness of GPE was increased. Thus, the ionic conductivity and hardness exhibit mutually conflicting properties depending on the content of the inorganic filler. Therefore, in order to obtain high ionic conductivity and high hardness, it is very important to derive the optimal content of the inorganic filler. Despite these limitations, the role of inorganic materials to inhibit the growth of lithium resin complexes has been studied. In particular, it is necessary to identify the growth or inhibition mechanism of the lithium resin assumptions during battery operation.

Therefore, the technical idea of the present invention is to provide a novel electrolyte having the advantages of the organic solid electrolyte and the inorganic solid electrolyte as described above simultaneously.

The composite gel polymer electrolyte membrane (CGPE) according to the technical concept of the present invention comprises a polymer substrate; And a core-shell structure composed of a core portion dispersed in the polymer substrate and having ion conductivity therein, and a shell portion covering the surface of the core material.

The polymer substrate may comprise a material that provides lithium ion conductivity and may include, for example, polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polyvinylidene fluoride (PVDF), and polymethylmethacryl And rate (PMMA).

The core portion may have a perovskite structure. Such a perovskite structure has a structure in which the coordination number of oxygen can be changed, and it is possible that oxygen ions are introduced into and discharged from the structure during charging and discharging. The core may be made of, for example, aluminum-doped lithium lanthanum titanate (A-LLTO), lithium aluminum germanium phosphate (LAGP), and lithium aluminum titanium phosphate, LATP). Said core portion, for example, _{(Li 0. 33 La 0.} 56) 1.005 Ti 0. ₉₉ Al _{0 . 01} O ₃ , and Li _{1 . 5} Al _{0 . 5 Ge 1 .5 (PO 4)} 3, Li 1. ₅ Al _{0 . 5} Ti _{1 .5} (PO ₄₎ may include at least any one of the _three.

The shell portion may comprise a material that provides a high hardness to the CGPE. The shell portion may comprise an amorphous phase. The shell portion may include a ceramic material and may include at least one of, for example, silicon oxide, silicon nitride, silicon oxynitride, zirconium oxide, zirconium nitride, zirconium oxynitride, and aluminum oxide.

It said shell portion m-SiO ₂ having an oxygen atom to provide a binding site . ≪ / RTI > The m-SiO ₂ Can be controlled using 3-glycidoxypropyl trimethoxysilane (GPTMS). At least one of hydroxyl group (OH < ^- & gt ^; ) and epoxy group may be formed in the shell part.

The core-shell structure may have a size ranging from 0.5 [mu] m to 3 [mu] m. The shell portion may have a thickness ranging from 1 nm to 10 nm. The polymer substrate and the core-shell structure may have a mass ratio ranging from 8: 2 to 2: 8. The core-shell structure may be uniformly distributed within the polymer substrate. The core-shell structure can suppress the growth of the resin anticipated of the lithium metal.

The composite gel polymer electrolyte membrane can be activated using a liquid electrolyte in which LiPF ₆ is mixed in a solution of ethylene carbonate and ethyl methyl carbonate. The composite gel polymer electrolyte membrane is prepared by mixing a liquid electrolyte prepared by mixing lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) with a tetraethylene glycol dimethyl ether (TEGDME) solution . ≪ / RTI >

However, the above-mentioned constituent materials of CGPE are illustrative, and the technical idea of the present invention is not limited thereto.

Experimental Example

Hereinafter, an experimental example in which CGPE according to the technical idea of the present invention is specifically implemented will be exemplarily described. In this embodiment, the polymer substrate is comprised of PVDF-HFP, the core portion is comprised of A-LLTO, and the shell portion is comprised of modified silicon oxide ("m-SiO ₂ "). Hereinafter, the core-shell structure will be abbreviated as "A-LLTO / m-SiO ₂ ".

Free-standing CGPE with high lithium ion conductivity, good process capability, and effective inhibition of lithium resin conformational growth was prepared by dispersing A-LLTO particles of perovskite structure into PVDF-HFP substrate Respectively.

The A-LLTO is used as a dispersed phase in the formation of electrolytes and has a high lithium ion conductivity (about 2.99x10 ^-3 S cm ^-1 ) at room temperature, a high lithium diffusion coefficient, a high thermal stability and a wide electrochemical range . However, the A-LLTO has a disadvantage in that it is chemically unstable when it comes into contact with lithium metal. Therefore, we designed such that the A-LLTO particles are surrounded by an extremely thin outer skin (i.e., shell) consisting of m-SiO _2. The m-SiO ₂ was formed to have a small thickness so as not to deteriorate the transmission of lithium ions to the A-LLTO even though it was in contact with the lithium metal. By the surface of such m-SiO _2, the adhesion of the PVDF-HFP substrate and the A-LLTO /-m SiO ₂ it can be increased. In addition, the m-SiO ₂ has an effect of reducing the growth of the lithium resin particles in the battery cell.

1. A- LLTO / m- SiO ₂  Characterization of

1-1. A- LLTO / m- SiO ₂  Manufacturing

A-LLTO /-m SiO ₂ may be prepared using a wet chemistry method as described below.

First, A-LLTO powder was prepared as a starting material. The A-LLTO powder is a material formed by replacing a part of titanium with aluminum in lithium lanthanum titanate. The composition of the A-LLTO powder, for example, _{(Li 0. 33 La 0.} 56) 1.005 Ti 0. ₉₉ Al _{0 . 01} O ₃ may be. In addition, the A-LLTO powder may further contain about 20 mol% of excess Li ₂ O. The A-LLTO powder was sintered at about 1350 DEG C to form pellets. The pellet was again pulverized to form powder again. The pulverization was carried out by primary pulverization using a mortar and pestle and secondary pulverization using zirconia balls for about 12 hours. Finally, A-LLTO powder with a micrometer size was formed.

Approximately 2 g of micrometer-sized A-LLTO powder was placed in about 100 ml of ethanol and mixed using ultrasonic waves to form a first suspension solution. Next, about 5 g of polyvinylpyrrolidone (PVP, K30) was put into deionized water and completely dissolved by using ultrasonic waves for about 30 minutes to form a second suspension solution. The first suspension solution and the second suspension solution were mixed and uniformly stirred at room temperature for about 8 hours to form a mixed solution of A-LLTO and PVP. The mixed solution was centrifuged in a centrifuge, and the supernatant was separated to obtain surfactant-stabilized A-LLTO. Wherein the supernatant stabilize A-LLTO were dispersed by putting into approximately 150 ml of ethanol, followed by deionized water to approximately 12 ml with aqueous ammonia to approximately ml (NH ₃ 28% by volume of Im) further added to form a final suspension solution. Subsequently, while maintaining the final suspension solution at about 40 ° C, about 5 ml of ethanol containing 20 μl tetraethoxysilane (TEOS) was added dropwise with stirring for about 5 minutes, Hydrolysis reaction. Then, about 10 [mu] l of 3-glycidoxypropyl trimethoxysilane (GPTMS) was added to control the thickness of the SiO ₂ formed. Subsequently, the mixed material was stirred vigorously for about 5 hours, separated by a centrifuge, and then washed three times with deionized water and ethanol to form a precursor powder. The precursor powder was dried in air at about 120 ° C. for 24 hours to form A-LLTO / m-SiO ₂ particles having a core-shell structure.

1-2. A- LLTO / m- SiO ₂  X-ray pattern analysis of

The crystal structure of A-LLTO / m-SiO ₂ was analyzed by X-ray diffractometer (XRD, Rigaku DIII ultima with Cu Ka radiation). Separate m-SiO ₂ particles were also analyzed for comparison

3 is a graph showing an X-ray diffraction pattern of A-LLTO / m-SiO ₂ constituting a composite gel polymer electrolyte according to an embodiment of the present invention.

Referring to FIG. 3, the X-ray pattern of A-LLTO / m-SiO ₂ is Li _{0 . 33} La _{0 . 56.} The TiO is very consistent with the X- ray pattern on the tetragonal of ₃ (JCPDS card No. 01-087-0935 call). Therefore, the A-LLTO core of A-LLTO / m-SiO ₂ is analyzed to have a perovskite structure. On the other hand, no peaks corresponding to SiO ₂ crystals or other silicon compound crystals were found. Similarly, the X-ray pattern of the individual m-SiO ₂ particles is interpreted as having an amorphous nature since it is enlarged and shows a small intensity peak, and thus the m-SiO ₂ of the A-LLTO / m-SiO ₂ is It is analyzed to have an amorphous structure.

1-3. A- LLTO / m- SiO ₂  Microstructure analysis of

The microstructure of A-LLTO / m-SiO ₂ was observed using a field emission scanning electron microscope (FE-SEM, S-4700 Hitachi) and a transmission electron microscope (TEM, Tecnai G2, Philips).

4 is a microstructure photograph of A-LLTO / m-SiO ₂ constituting a composite gel polymer electrolyte according to an embodiment of the present invention.

In FIG. 4, (a) is a scanning electron micrograph of A-LLTO / m-SiO ₂ , and (b), (c) and (d) are transmission electron micrographs of A-LLTO / m-SiO ₂ . (C) is an enlarged view of the rectangular area of (b), and (d) is an enlarged view of the rectangular area of (c).

4, about A-LLTO / m-SiO ₂ has a relatively uniform size, for example, can have a size ranging from about 0.5 μm to about 3 μm, for example, Can have a size in the range of about 2 [mu] m. In addition, the A-LLTO particles are surrounded by a very thin m-SiO ₂ shell. As shown in the high-resolution photograph (d), it can be confirmed that a clear interface is formed between the A-LLTO and the m-SiO ₂ layer. The thickness of the m-SiO ₂ layer may have a thickness in the range of, for example, from about 1 nm to about 10 nm, and may have a thickness in the range of, for example, about 4 nm to about 6 nm. In addition, the interplanar distance corresponding to the (101) planes of the A-LLTO tetragonal lattice was about 0.35 nm.

1-4. A- LLTO / m- SiO ₂  Chemical structure analysis

The chemical structure of A-LLTO / m-SiO ₂ was analyzed by Fourier transform infrared spectroscopy (FTIR, Prestige-21 Shimadzu). As a comparative example, A-LLTO / SiO _{2 in} which SiO ₂ was not modified was also analyzed.

5 is a graph showing Fourier transform infrared spectroscopy analysis of A-LLTO / m-SiO ₂ constituting a composite gel polymer electrolyte according to an embodiment of the present invention.

Referring to FIG. 5, absorption peaks at 473 cm ^-1 , 798 cm ^-1 , 1099 cm ^-1 and 949 cm ^-1 in the case of the comparative A-LLTO / SiO ₂ , The bending vibration of O-Si, the symmetric stretching vibration of Si-O-Si, the asymmetric stretching vibration of Si-O-Si, and the flexural vibration of Si-OH do. In addition, the absorption peaks at 1651 cm ^-1 and 3440 cm ^-1 correspond to the flexural vibration of -OH and the stretching vibration of -OH, respectively, and are caused by hydrolysis of TEOS. Also, the double shoulder peak at 2363 cm ^-1 is analyzed by stretching vibration of carbon dioxide.

On the other hand, in the case of A-LLTO / m-SiO ₂ , the absorption intensity of -OH groups at 1651 cm ^-1 and 3440 cm ^-1 was smaller than that of A-LLTO / SiO ₂ . This is because the -OH group on the SiO ₂ surface was replaced with GPTMS. In addition, 2927 cm from the corresponding A-LLTO / m ₂ SiO-to the stretching vibration of the -CH ^{group-peak 1} was observed. From these results, it can be seen that the GPTMS is chemically adsorbed on the oxygen atom constituting SiO ₂ on the surface of A-LLTO / m-SiO ₂ . On the other hand, physically adsorbed GPTMS and reaction by-products on the surface of A-LLTO / m-SiO ₂ were analyzed by centrifugation in the manufacturing process and by cleaning with deionized water and ethanol. Since the GPTMS is chemically adsorbed on the surface of the m-SiO ₂ , the thickness of the SiO ₂ shell covering the A-LLTO core can be controlled to several nanometers. By this control, aggregation of the SiO ₂ particles was prevented.

6 is a schematic diagram of A-LLTO / m-SiO ₂ of a core-shell structure making up a composite gel polymer electrolyte according to one embodiment of the present invention.

6, the A-LLTO / m-SiO ₂ 131 is located inside the A-LLTO 132 as a core, and the surface of the A-LLTO 132 is surrounded by m-SiO ₂ 133). The m-SiO ₂ 133 includes silicon atoms 134 and oxygen atoms 135 surrounding the A-LLTO 132 and is also bonded to the silicon atoms 134 and surrounds the A-LLTO 132 And oxygen atoms 136 that provide bonding sites to other groups.

Hydrogen ions may be bonded to the oxygen atom 136 to form a hydroxyl group (OH ^- ) 137. The GPTMS may be chemically adsorbed to the oxygen atom 136 to form an epoxy group 138. The hydroxyl group 137 is partially formed on the surface of the m-SiO ₂ 133, and can easily capture water, moisture, or impurities by hydrogen bonding or the like. The epoxy group 138 can increase ionic conductivity and stability of the phase boundary. Therefore, it is possible to enhance the interfacial interactions between the A-LLTO / SiO _m-2 (131) with the polymeric base material.

By forming the A-LLTO / m-SiO ₂ 131 through the surface modification process, the ion conductivity of the CGPE can be increased and the contamination by moisture that can diffuse from the cathode in the lithium air battery can be blocked. In addition, the A-LLTO / m-SiO ₂ (131) not only maintains high ionic conductivity, but also can increase the mechanical hardness of CGPE. However, if the content of A-LLTO / m-SiO ₂ is excessively increased, the relative volume ratio of the polymer base having lithium ion conduction as a main function is reduced, so there is a possibility of reducing the ion conductivity of CGPE.

2. Of CGPE  Character analysis

2-1. Of CGPE  Produce

The A-LLTO / m-SiO ₂ particles, PVDF-HFP, and DBP prepared by the above-mentioned method were added to acetone at a weight ratio of 8: 2: 3 and stirred at about 50 ° C to form a homogeneous mixture . The mixture was cast on a glass plate using a doctor blade, and then dried in a vacuum oven at about 50 DEG C for about 4 hours to form a dried translucent film. The membrane was then immersed in about 500 ml of methanol for about 4 hours to remove the DBP and then dried in a vacuum oven at about 70 < 0 > C. The dried material was cut into a circular shape in a glove box before the activation treatment to prepare a CGPE membrane.

Then, the CGPE membrane was immersed in the liquid electrolyte for about 2 hours or longer to activate the CGPE membrane. The liquid electrolyte may vary depending on the type of battery cell. In the present invention, a CGPE membrane applied to a lithium ion polymer battery was activated by using a liquid electrolyte in which 1 M of LiPF ₆ was mixed in a 50:50 volume ratio mixture of EC and EMC. On the other hand, in the present invention, a CGPE membrane applied to a lithium air cell was activated using a liquid electrolyte in which a 1 M LiTFSI was mixed with a TEGDME solution.

However, the liquid electrolyte is exemplified, and the technical idea of the present invention is not limited thereto. For example, the liquid electrolyte may be at least one selected from the group consisting of ethylene carbonate (EC), ethylmethyl carbonate EMC, diethyl carbonate (DEC), dimethyl carbonate (DMC), propylene carbonate carbonate, PC), methylpropyl carbonate (MPC), diprophyl carbonate (DPC), dimethyl sulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, vinylene carbonate, sulfolane, gamma- And one or a mixture of two or more selected from the group consisting of lactone, propylene sulfite, tetrahydrofuran, and tetraethylene glycol dimethyl ether (TEGDME).

2-2. Of CGPE  Transparency Analysis

7 is a photograph showing transparency of a composite gel polymer electrolyte according to an embodiment of the present invention.

In FIG. 7, all the electrolytes were activated using a liquid electrolyte in which 1 M of LiPF ₆ was mixed in a 50:50 mixed volume of EC and EMC as described above. (A) is a comparative example in the case of GPE after being composed and activated by PVDF-HFP membrane, (b) is an example of PVDF-HFP and A-LLTO / m-SiO ₂ With a mass ratio of 2: 8 and is the case of CGPE after activation.

Referring to FIG. 7, in the case of (a), since the grid of the bottom material disposed at the lower end of the GPE is very clearly displayed, it can be seen that the GPE changes almost transparently after being activated. On the other hand, in the case of (b), since the lattice of the bottom material disposed at the lower end of the CGPE is not visible, the CGPE exhibited opaque characteristics. The opaque characteristic of the CGPE is analyzed because the A-LLTO / m-SiO ₂ particles contained in the CGPE scatter light.

2-3. Of CGPE  Electrochemical characterization

The electrochemical characteristics of the CGPE were analyzed by measuring electrochemical impedance spectroscopy at a frequency of 0.1 Hz to 1 MHz and a voltage amplitude of 10 mV using a ZIVE SP2 measuring instrument. Particularly, the influence of the mass ratio on the electrochemical characteristics was analyzed by changing the mass ratio of A-LLTO / m-SiO ₂ and PVDF-HFP in the CGPE.

8 is a graph showing changes in electrochemical characteristics depending on the mass ratio of A-LLTO / m-SiO ₂ and PVDF-HFP constituting the composite gel polymer electrolyte according to an embodiment of the present invention

In FIG. 8,% refers to the content ratio of A-LLTO / m-SiO ₂ to the total mass of A-LLTO / m-SiO ₂ and PVDF-HFP. For example, 0% (ie, 10: 0) refers to the case where the membrane is composed of only PVDF-HFP without A-LLTO / m-SiO ₂ and 80% Refers to a case where the content of LLTO / m-SiO ₂ is 80 wt% and the content of PVDF-HFP is 20 wt%. All membranes were activated using a liquid electrolyte in which 1 M of LiPF ₆ was mixed in a 50:50 mixed volume of EC and EMC as described above.

Referring to Figure 8, all niequist graphs exhibited a single partial arc shape. As shown in the graph inserted in FIG. 8, the bulk resistance showed a minimum value at the A-LLTO / m-SiO ₂ content of 0 wt% (i.e., 10: 0). The values in the range of 20 wt% (i.e., 8: 2) to 80 wt% (i.e., 2: 8) of the A-LLTO / m-SiO ₂ were within similar ranges. On the other hand, the maximum value was obtained when the content of A-LLTO / m-SiO ₂ was 90 wt% (that is, 1: 9). From the results of Fig. 8, the ion conductivity calculated in consideration of the bulk resistance and the thickness is shown in Table 1 below.

Table 1 is a table showing changes in characteristics of A-LLTO / m-SiO ₂ and PVDF-HFP constituting the composite gel polymer electrolyte according to one embodiment of the present invention.

PVDF-HFP
: A-LLTO / m _2-SiO
Mass ratio The content of A-LLTO / m-SiO ₂
(wt%) Electrolyte
thickness
(μm) Bulk resistance
(Ω) Ion conductivity
(S cm ^-1 ) Hardness before activation
(H _D ) 10: 0 0 85 2.73 1.56 x 10 ^-3 22.6 8: 2 20 102 3.57 1.43 x 10 ^-3 45.7 6: 4 40 96 3.53 1.36 x 10 ^-3 56.8 4: 6 60 109 4.22 1.29 x 10 ^-3 67.8 3: 7 70 104 4.13 1.29 x 10 ^-3 74.5 2: 8 80 95 3.89 1.22 x 10 ^-3 78.9 1: 9 90 92 6.67 0.69 x 10 ^-3 80.1

Referring to Table 1, as the A-LLTO / m-SiO ₂ content in the CGPE increased showed a tendency that the ion conductivity decreases, in particular, A-LLTO / m-SiO ₂ content of 80 wt% (i.e., 2 (Ie, 2: 8) and 90 wt% (ie, 1: 9) of the A-LLTO / m-SiO ₂ content was relatively slow, Ionic conductivity was drastically reduced.

2-4. CGPE Membrane  Mechanical Characterization

The mechanical properties of the CGPE membrane were measured using a Shore hardness meter (GS-702N Hardmatic Mitutoyo) to measure the penetration depth of a durometer indenter to calculate the Shore D hardness (H _D ) Respectively. Particularly, the influence of the mass ratio on the mechanical properties was analyzed by changing the mass ratio of A-LLTO / m-SiO ₂ and PVDF-HFP in the CGPE. The mechanical properties were performed on membranes prior to performing activation with a liquid electrolyte.

Referring to Table 1, it was that the hardness increases with the A-LLTO / m-SiO ₂ content in the CGPE increased, A-LLTO / m-SiO ₂ content of 80 wt% (i.e., 2: 8) and 90 wt % (I.e., 1: 9).

2-5. Of CGPE  Charge-discharge Cycle  Character analysis

Referring to Table 1, the content of A-LLTO / m-SiO ₂ in CGPE is preferably as low as possible in terms of ionic conductivity, and is preferably as high as possible in terms of hardness. Therefore, the charge-discharge cycle stability was tested to derive the optimum content of A-LLTO / m-SiO ₂ in CGPE. For the charge-discharge cycle stability test, CGPE was prepared by varying the content of A-LLTO / m-SiO ₂ , and a lithium polymer battery cell (Li-LiCoO ₂ ) was prepared as described below.

9 is a graph showing the charge-discharge cycle stability depending on the mass ratio of A-LLTO / m-SiO ₂ and PVDF-HFP constituting the composite gel polymer electrolyte according to an embodiment of the present invention.

Referring to FIG. 9, the charge-discharge cycle stability is indicated by the capacity retention. If the above-LLTO A / m-SiO ₂ is not compared with the case (0 wt%), the A-LLTO / m ₂ SiO-holding capacity also, the entire charge-discharge has been increased with respect to the cycle. In particular, when the content of A-LLTO / m-SiO ₂ was 80 wt% (that is, 2: 8), the capacity retention was higher for the entire charge-discharge cycle. Therefore, it can be estimated that the content of A-LLTO / m-SiO ₂ is 80 wt% (i.e., 2: 8).

Therefore, the results of experiments in which the content of A-LLTO / m-SiO ₂ is 80% (that is, 2: 8) will be described below. &Quot; CGPE "described below includes PVDF-HFP and A-LLTO / m-SiO ₂ in a mass ratio of 2: 8, that is, the content of A-LLTO / m-SiO ₂ is 80% , 2: 8).

2-6. Of CGPE  Microstructure analysis

10 is a scanning electron micrograph of a composite gel polymer electrolyte membrane and a composite gel polymer electrolyte according to an embodiment of the present invention.

In FIG. 10, (a) shows, as a comparative example, a GPE membrane not containing A-LLTO / m-SiO ₂ but composed only of PVDF-HFP, (b) showing PVDF-HFP and A- / m-SiO CGPE membrane consisting of _2, (c) is a comparative example, GPE, after activating the GPE membrane of (a) (d) is enabled, the CGPE membrane of, (c) as an embodiment of the present invention Gt; CGPE < / RTI > The activation was carried out using a liquid electrolyte in which 1 M of LiPF ₆ was mixed with a solution in which EC and EMC were mixed in a volume ratio of 50:50 as described above. For reference, the membranes and electrolytes were cooled with liquid nitrogen and the surface was coated with platinum using sputtering, and the microstructure was observed using a scanning electron microscope as described above in Section 1.3.

Referring to FIG. 10 (a), the GPE membrane, which is composed of only PVDF-HFP without A-LLTO / m-SiO ₂ , has micrometer-sized pores and mesopores smaller in size, Porous structure. These micrometer-sized pores and medium-sized pores can effectively accommodate the liquid electrolyte in the activation process and in the gelling process of the membrane. After activation by the liquid electrolyte, as shown in Fig. 10 (c), the GPE was swollen as a whole, pores disappeared, and a smooth surface was formed. Also, consistent with the results of Figure 7, the GPE was almost transparent overall. Further, as shown in Table 1, the A-LLTO / m _SiO-2, not including the ionic conductivity of the GPE consists only of PVDF-HFP is 1.56 × 10 ^-3 S cm ^- a ^first, substantially equal to the known value Or slightly higher.

10 (b), a CGPE membrane composed of PVDF-HFP and A-LLTO / m-SiO ₂ has a relatively rough surface, and the A-LLTO / m-SiO ₂ particles Were uniformly distributed. The micrometer-sized pores observed in Fig. 10 (a) were scarcely shown because of the strong adhesion between the A-LLTO / m-SiO ₂ particles and the PVDF-HFP substrate in the CGPE, Of the pores in the sample. After activation by the liquid electrolyte, it showed a microstructure similar to that of Fig. 10 (c). Specifically, as shown in Fig. 10 (d), the CGPE expanded as a whole, pores disappeared, Respectively.

2-7. CGPE Membrane  X-ray pattern analysis

The crystal structure of the CGPE membrane was analyzed by X-ray diffractometer described in 1.2. Further, comparing the GPE membrane and A-LLTO / m ₂ SiO-particles and does not include the A-LLTO / m _SiO-2 consists only of PVDF-HFP were also analyzed.

11 is a graph showing an X-ray diffraction pattern of a composite gel polymer electrolyte membrane according to an embodiment of the present invention.

Referring to FIG. 11, the CGPE membrane showed peaks at the same positions as those generated by the A-LLTO / m-SiO ₂ particles, and the peak size was decreased. This is analyzed because of the presence of PVDF-HFP substrate in the CGPE membrane. The CGPE membrane did not show a peak at 20.4 ° generated by PVDF-HFP in the GPE membrane because the A-LLTO / m-SiO ₂ particles reduced the crystallinity of the polymer. Therefore, it can be seen that the CGPE membrane contains more amorphous regions than the GPE membrane, and thus the absorption of the liquid electrolyte and the transmission of lithium ions can be facilitated. As a result, when the CGPE membrane is activated by the liquid electrolyte, the retention of the liquid electrolyte of the CGPE and the ion conductivity are expected to be improved as compared with the GPE.

When Interestingly, see Table 1, GPE (mass ratio 10: In the case of zero), the ion conductivity of 1.56 x 10 ^-3 S ^cm-1, and are all CGPE indicates the lower levels, particularly the mass ratio 2:08 Of 1.22 x 10 ^-3 S cm ^{- 1} in the case of. However, the present inventors, according to a study published in the conventional, A-LLTO / m SiO-ion conductivity inside the A-LLTO ₂ particles is 2.99 x 10 ^-3 S cm ^- reported very high to ^1. The However, the ionic conductivity of A-LLTO / m-SiO _{2 in which} the outer m-SiO ₂ shell is present is reduced to 1.05 x 10 ^-4 S cm ^-1 as shown in Fig. 12 below.

2-8. CGPE Membrane  A- LLTO / m- SiO ₂  Electrochemical characterization of

Hereinafter, a description of the effect of m-SiO ₂ for the ion conductivity of the A-LLTO / SiO _2-m. To this end, the A-LLTO / m-SiO ₂ powder was formed into pellets and the pellets were inserted into A-LLTO / m-SiO ₂ powder of the same composition and then sintered at about 1350 ° C for about 6 hours. The surface of the sintered pellet was polished using sandpaper. The pellets had a diameter of 6 mm and a thickness of 0.8 mm. Both surfaces of the pellet were coated with platinum, silver glue was applied, and heat treatment was performed at about 500 캜 for about 1 hour. Then, the lithium ion electric conductivity was measured at 25 DEG C using the impedance measurement apparatus of 2.3 above.

12 is a graph showing electrochemical characteristics of A-LLTO / m-SiO ₂ constituting a composite gel polymer electrolyte according to an embodiment of the present invention. In Fig. 12, there is shown a niequest graph of the measured A-LLTO / m-SiO ₂ and an equivalent circuit corresponding thereto.

12, one arc corresponding to the ion conductivity was observed in the high frequency region, and a spike corresponding to the blocking effect of the platinum electrode in the low frequency region was observed. Based on these niequist graphs, an equivalent circuit was constructed. In the equivalent circuit, the resistor R _b may represent a crystal element, the resistor R _gb , a constant phase element CPE _gb may represent a grain boundary element, and the positive phase element CPE _e may represent an electrode polarization element. Simulation and fitting were carried out for these Nyquist graphs and equivalent circuits to calculate grain and grain boundary conductivities.

Grain conductivity of the A-LLTO /-m SiO ₂ is 1.29 x 10 ^-3 S cm ^- was calculated to be ^1, the grain boundary conductivity of 1.14 x 10 ^-4 S cm ^- was calculated to be ^1. Accordingly, the total ionic conductivity of 1.05 x 10 ^-4 S cm ^- was calculated to be ^1. On the other hand, A-LLTO the grain conductivity without ^{_{m-SiO 2 2.99 x 10 -3}} S cm -1, the grain boundary conductivity of 3.55 x 10 ^-4 S cm ^-1, the total ionic conductivity of 3.17 x 10 ^-4 S cm ^{- 1} It is known. Thus, the m-SiO ₂ yi-A-LLTO LLTO the A / m-SiO ₂ as compared to not having a relatively low ionic conductivity, which is analyzed to be due to the blocking effect of the conductivity-m SiO _2.

Therefore, in the above CGPE, an increase tendency of ionic conductivity as the amorphous region is increased can be reduced by the presence of m-SiO ₂ having electrical resistance. Nevertheless, the ionic conductivity of the CGPE can be compared to the ionic conductivity of the GPE.

3. Of CGPE  Applicability Analysis to Lithium Metal Electrodes

3-1. CGPE  Symmetric inclusion Lithium ion polymer  Manufacture of battery cell

Then, CGPE (mass ratio 2: 8) according to the technical idea of the present invention was interposed between lithium metals to produce a symmetric lithium ion polymer battery cell having a Li / CGPE / Li structure.

As a comparative example, a mixture of a GPE membrane and glass microfiber (Whatman, GF / F, 150) in a volume ratio of 50:50 in EC and EMC, which is the same liquid electrolyte as CGPE, was mixed with 1 M of LiPF ₆ GPE and a glass microfibre electrolyte were respectively formed. Using these, a symmetrical lithium ion battery cell having a Li / GPE / Li structure and a symmetrical lithium battery having a Li / glass microfine electrolyte / Li structure Ion battery cells were prepared.

3-2. CGPE  Symmetric inclusion Lithium ion polymer  Charge-discharge of the battery cell Cycle  Character analysis

To confirm the applicability of the CGPE to the lithium metal electrode, a charge-discharge cycle test was performed. The above-described symmetrical lithium ion battery cells 0.48 mA cm in constant current mode (galvanostatically) ^- applying a current density of ² to charge - we implemented the discharge cycle, the charge - was the discharge duration is approximately 2 hours, respectively, at a rate of 0.5 C Respectively.

13 is a graph showing a constant current cycle characteristic of a composite gel polymer electrolyte according to an embodiment of the present invention.

Referring to FIG. 13, the CGPE exhibited overvoltage in the initial several cycles. However, as cycles repeatedly progressed, the overvoltage gradually disappeared and stabilized. This overvoltage is analyzed as the process of activating the surfaces of the electrodes during the initial several charge-discharge cycles.

As the charge-discharge cycle progressed, the glass fiber of the comparative example exhibited abnormal operation behavior after 1093.8 hours, and the GPE of the comparative example exhibited abnormal operation behavior after 1193.9 hours. From the abnormal behavior, it is analyzed that the glass microfibers and the GPE can not effectively suppress the growth of the lithium resin phase during the charge-discharge cycle and can not effectively suppress the undesired reaction between the lithium metal and the electrolyte.

On the other hand, the CGPE exhibits no abnormal operation behavior up to 1921.8 hours, corresponding to almost twice the time of other comparative examples. These results indicate that the CGPE is very stable with respect to the lithium metal electrode and that the CGPE effectively inhibits the lithium metal phase growth and the undesired reaction between the lithium metal and the electrolyte. These results are consistent with the results of the electrochemical characteristics of FIG. 14 below.

3-3. CGPE  Symmetric inclusion Lithium ion polymer  Electrochemical Characterization of Battery Cell

The electrochemical characteristics of a symmetric lithium ion polymer battery cell containing CGPE were measured and analyzed by electrochemical impedance spectroscopy in the same manner as in 2.3.

FIG. 14 is a graph showing electrochemical characteristics of a composite gel polymer electrolyte according to an embodiment of the present invention over time. FIG.

In Fig. 14, (a) shows the case of the comparative example, GPE, and (b) shows the case of CGPE. Further, current density of 0.5 mA cm ^-2 was continuously applied to the symmetric lithium ion polymer battery cell, and the change with time was measured at room temperature.

Referring to FIG. 14, the GPE shows an increase in impedance value with time, whereas the CGPE has a relatively small change in impedance value over time. Thus, it is analyzed that the CGPE is more stable to the lithium metal, and that the CGPE effectively inhibits lithium resin phase growth and the undesired reaction between the lithium metal and the electrolyte relative to the GPE.

3-4. CGPE  Symmetric inclusion Lithium ion polymer  Microstructure analysis of battery cell

15 is optical micrographs showing microstructural changes over time of the composite gel polymer electrolyte according to one embodiment of the present invention.

In Fig. 15, (a) shows the case of GPE and (b) shows the case of CGPE. Further, current density of 0.5 mA cm ^-2 was continuously applied to the symmetrical lithium ion polymer battery cell, and the change with time was observed using an optical microscope (Leica ICC50 HD) at room temperature.

Referring to FIG. 15 (a), in the case of the GPE, the growth of the lithium resin particles prominently increased with time. In the case of the GPE, it was confirmed that, immediately after assembling the battery cell, a non-uniform solid electrolyte interface (SEI) layer was formed on the surface of the lithium electrode. During charging, the lithium concentration in the thin or defective portion of the SEI layer is increased, resulting in strong lithium ion flow, and thus, the growth of the lithium resin particles is promoted. For example, at the point indicated by the arrow in Fig. 17 (a), the growth of the lithium resin assumptions begins and expands. After about 14 hours, the lithium resin was observed to have grown to a length of about 0.2 mm, and after about 80 hours it was observed that the lithium resin particles expanded across the surface.

On the other hand, referring to Fig. 15 (b), in the case of the CGPE, similar to that observed after 14 hours in the case of the GPE, a resin of 0.2 mm in length was observed after about 40 hours. In addition, similar to that observed after 80 hours in the case of the GPE, it was observed after 210 hours that the lithium resin assumptions extended throughout the surface.

Thus, the CGPE is analyzed to have the ability to inhibit the growth of lithium resin complexes relative to the GPE. It is analyzed that the presence of micro-sized A-LLTO / m-SiO ₂ particles in the CGPE increases the hardness of the gel polymer and thus effectively inhibits lithium-based positive growth.

3-5. CGPE  Included Lithium ion polymer  Analysis of electrochemical stability range of battery cell

16 is a graph showing an electrochemical stability range of a composite gel polymer electrolyte according to an embodiment of the present invention.

16, a lithium ion polymer battery cell has a structure of stainless steel / CGPE / Li, and a CGPE is a liquid electrolyte in which 1 M of LiPF ₆ is mixed in a 50:50 volume ratio mixture of EC and EMC Or activated with a liquid electrolyte mixed with 1 M of LITFSI in TEGDME solution.

Referring to FIG. 16, the intersection point of the cell potential axis (x-axis) and the extension line of the graph on the high potential is set as the maximum value, and the range up to the maximum value is set as the stable range. In the case of using the two liquid electrolytes, the stability range was 5 V or less. In such a stable range, it is analyzed that the components are not decomposed. Therefore, in the following, a voltage of 5 V or less was applied to the cell stability measurement.

4. CGPE  Included Lithium ion polymer  Characteristic analysis of battery cell

4-1. CGPE  Included Lithium ion polymer  Manufacture of battery cell

In order to prepare a lithium ion polymer battery cell including CGPE, a LiCoO ₂ cathode was formed in the following manner. Commercially available LiCoO ₂ (Sigma Aldrich 99.8%), Super P Carbon and polyvinylidene fluoride (N-methyl-2-pyrrolidone, NMP) PVFF) were mixed at 8: 1: 1 to form a slurry. After coating the slurry on an aluminum foil and dried in a vacuum oven at about 120 ℃ for about 12 hours to form a LiCoO ₂ cathode. The weight load of the cathode was controlled to 8 mg cm <& quot ^{; 2 &} gt ;.

Next, a lithium metal anode, a CGPE (mass ratio 2: 8) according to the technical idea of the present invention, and the LiCoO ₂ cathode were assembled to prepare a lithium ion polymer battery cell having a Li / CGPE / LiCoO ₂ structure.

As a comparative example, a mixture of a GPE membrane and glass microfiber (Whatman, GF / F, 150) in a volume ratio of 50:50 in EC and EMC, which is the same liquid electrolyte as CGPE, was mixed with 1 M of LiPF ₆ GPE and glass microfibre electrolytes were formed by immersing them in a mixed liquid electrolyte. Using these, a lithium ion battery cell having a Li / GPE / LiCoO ₂ structure and a lithium ion battery cell having a Li / glass microfine electrolyte / LiCoO ₂ structure Ion battery cells were prepared.

4-2. CGPE  Included Lithium ion polymer  Charge-discharge of the battery cell Cycle  Character analysis

As analyzed in the above 3-5, it was found out that the electrochemical stability range was 5V in the case of using CGPE in the lithium ion polymer battery cell, and therefore it is expected that the operation is possible up to 4.5V. A lithium ion polymer battery cell having a lithium metal anode may be charged at a charging rate that is very lower than the discharging rate in order to suppress or minimize the lithium resin phase growth due to the charge-discharge cycle. For example, the charge rate may be about one fifth of the discharge rate.

In the present invention, the lithium resin phase positive growth inhibiting ability of the CGPE for improving the cycle characteristics of the battery cell was examined. Thus, a lithium ion polymer battery cell having the above-described Li / GPE / LiCoO ₂ structure was charged at an equal charging rate and discharging rate of 0.5 C at a battery cell potential in the range of 3.5 V to 4.2 V, 500 charge- - discharge cycle test was carried out. As a comparative example, a battery in which glass microfibers containing a solution in which 1 M of LiPF ₆ was mixed as a liquid electrolyte in a solution in which EC and EMC were mixed in a volume ratio of 50:50, and a cell composed of an electrolyte and EC and EMC in a volume of 50% : 50 A charge-discharge cycle test was also performed on a cell composed of a GPE electrolyte containing a solution of 1 M of LiPF ₆ in a mixed solution as a liquid electrolyte.

17 is a graph showing a change in capacitance of a lithium ion polymer battery cell including a composite gel polymer electrolyte according to an embodiment of the present invention in accordance with a charge-discharge cycle.

18 is a graph showing the coulomb efficiency and the cell cell potential according to the charge-discharge cycle of the lithium ion polymer battery cell including the composite gel polymer electrolyte according to an embodiment of the present invention.

In Figures 17 and 18, 500 charge-discharge cycles were performed at a charge-discharge rate of 0.5C. In FIG. 18, (a) shows the case of CGPE, (b) shows the case of GPE, which is a comparative example, and (C) shows the case of glass microfibers, which are comparative examples.

17 and 18, in the initial charge-discharge cycle, the specific capacity of the CGPE is 153 mAh g ^-1 , the specific capacity of the GPE is 157 mAh g ^-1 , and the specific capacity of the glass microfibers is 166 mAh g ^-1 . Therefore, in the initial charge-discharge cycle, the cost amount of the CGPE was smaller than the specific capacity of the GPE and the specific capacity of the glass microfibers.

However, after performing 12 charge-discharge cycles, the cost of CGPE is increased to a maximum value of 165 mAh. This result is analyzed because the activation of the cell has progressed in the first 12 charge-discharge cycles, which is consistent with the result of FIG. 13 obtained using the symmetric lithium ion polymer battery cell. In the charge-discharge cycles up to the first 100 cycles, the CGPE, the GPE, and the glass microfibers exhibit similar behavior and numerical values. However, after performing 100 charge-discharge cycles, the GPE and the glass microfibers show a marked decrease in the non-capacity, which is due to an increase in impedance as shown in Fig. 19 (b) Is analyzed.

On the other hand, after 500 charge-discharge cycles, the CGPE exhibited 80.5% of the initial specific capacity and showed a coulombic efficiency of 99.2% or more. However, in the case of the comparative examples of GPE and glass microfibers, a significant non-dose reduction appeared. The GPE showed 47.7% of the initial specific capacity after 500 charge-discharge cycles and 98.1% of the Coulomb effect. The glass microfibers exhibited 32.6% of the initial specific capacity after 500 charge-discharge cycles and 96% of the Coulomb effect. The glass microfibers exhibited the largest variation amplitude.

19 is a graph illustrating electrochemical characteristics of a lithium ion polymer battery cell including a composite gel polymer electrolyte according to an embodiment of the present invention and a model therefor.

19, (a) is the electrochemical characteristic before the charge-discharge cycle is performed, and (b) is the electrochemical characteristic after 500 charge-discharge cycles.

Referring to FIG. 19 (a), before performing the charge-discharge cycle, the CGPE has a higher impedance value than the GPE and the glass microfibers.

Referring to FIG. 19 (b), contrary to the initial impedance characteristic of FIG. 19 (a), the GPE and the glass microfibers were greatly increased in impedance value compared to the CGPE after 500 charge-discharge cycles .

An equivalent circuit model as shown in Fig. 19 was established in order to analyze the effect of the CGPE on the impedance characteristic change before the charge-discharge cycle and 500 times of the charge-discharge cycle. The model 1 of FIG. 19 (a) corresponds to the state before the charge-discharge cycle, and the model 2 of FIG. 19 (b) corresponds to 500 times of the charge-discharge cycle.

Referring to the model 1 of FIG. 19 (a), immediately after the lithium ion polymer battery cell is manufactured, electrolyte resistance R _e , double layer capacitance (CPE _dl ), charge transfer resistance (R _ct ), and bug impedance impedance (Z _w ) and intercalation capacitance (C _L ).

Referring to the model 2 of FIG. 19 (b), after the charge-discharge cycle is performed, the passivation layer is formed on the surfaces of the electrodes, so that the shape of the impedance characteristic is changed. For example, before the charge-discharge cycle, as shown in FIG. 19 (a), a half-circle shape is shown. After the charge-discharge cycle is performed, as shown in FIG. 19 (b) Respectively. The semicircle appearing in the high frequency to middle frequency region corresponds to the resistance (R _f ) of the electrode surface layer covering the LiCoO ₂ cathode and the Li anode, and the other half circle appearing in the low frequency region corresponds to the charge transfer resistance (R _ct ). Therefore, the charge-impedance characteristics after performing the discharge cycle, the electrolyte resistance (R _e), connected in parallel with the R _{f CPE f (R f // CPE f} ), connected in parallel with the R _ct Z _w CPE _dl (R _ct Z _w // CPE _dl ), and C _L. The and bug elements (Z _w ) in Model 1 and Model 2 represent the diffusion of lithium ions in the electrolyte, in the solid electrolyte interface and from intercalation between LiCoO ₂ particles.

Table 2 is a table showing the impedance parameters obtained using Model 1 and Model 2.

Sample Immediately after battery assembly 500 charge - after discharge cycle Glass
Fine fiber GPE CGPE Glass
Fine fiber GPE CGPE R _c (Ω) 4.95 5.14 5.41 5.15 5.16 5.50 R _f (Ω) - - - 210.88 199.36 152.50 CPE _f C _f (F) - - - 1.99 × 10 ^-4 1.90 x 10 ^-3 2.83 × 10 ^-3 n - - - 0.905 0.933 0.938 R _ct (Ω) 28.76 33.97 39.90 88.38 79.66 71.48 CPE _dl C _dl (F) 2.27 x 10 ^-4 2.64 x 10 ^-5 1.84 x 10 ^-5 5.81 × 10 ^-6 4.68 × 10 ^-5 7.72 × 10 ^-5 n 0.728 0.829 0.812 0.711 0.686 0.640 W (Ω ^-1 s ^1/2 ) 8.57 × 10 ^-2 4.26 × 10 ^-2 9.52 x 10 ^-3 2.60 x 10 ^-2 7.31 x 10 ^-2 1.99 x 10 ^-1 C _L (F) 1.89 x 10 ^-2 1.28 x 10 ^-2 1.89 x 10 ^-3 9.41 x 10 ^-2 2.577 3.500

Referring to Table 2, the CGPE exhibited an electrolyte resistance (R _e ) of 5.41 Ω and a charge transfer resistance (R _ct ) of 39.9 Ω. The GPE (R _e = 5.14, R _ct = 33.97 Ω) Was slightly higher than that of glass microfiber (R _e = 4.95 Ω, R _ct = 28.76 Ω). Thus, in the first cycle, the CGPE battery cell has a lower capacity than other cases. As the charge-discharge cycle is performed, the charge transfer resistance is increased, and the R _f element appears, thereby increasing the total impedance. Therefore, as shown in FIG. 17, it can be interpreted that the capacity is reduced as the charge-discharge cycle is performed. Note that after 500 charge-discharge cycles, the electrolyte resistance change of the battery cells is neglected, because the electrolytes are stable during the charge-discharge cycle. Also, the interface resistance (R _i ) calculated from the sum of R _f and R _ct of the CGPE is 223.98, which is a very low value as compared with other battery cells. For reference, the glass microfibers exhibited an interface resistance of 299.26? And an interface resistance of 279.02? In the GPE battery cell. These results indicate that the electrode interface resistance is decreased by the addition of A-LLTO / m-SiO _{2 in} the CGPE battery cell. In addition, the charge-discharge cycle characteristics of the battery cell including the CGPE have been greatly improved.

5. CGPE  Characterization of Lithium Air Battery Cells Containing

5-1. CGPE  Manufacture of a Lithium Air Battery Cell Containing

In order to manufacture a lithium ion polymer battery cell including CGPE, a MnO ₂ @ Ni cathode was formed in the following manner.

The MnO ₂ catalysts were immersed in a 500 ml solution containing 20 mM KMnO ₄ , 10 mM MnSO ₄ and a few drops of NH ₃ (28 vol%) on a clean nickel foam sheet, Lt; 0 > C for about 5 hours and rinsed in deionized water to remove unwanted impurities. After the growth reaction, the nickel sheet was covered with the MnO ₂ catalyst. Then, the nickel sheet covered with the MnO ₂ catalysts was heat-treated at a temperature of about 450 ° C for about 5 hours. The nickel sheet covered with MnO ₂ catalysts was then punched to prepare a disk shape having a diameter of 16 mm, which was used as a cathode (i.e., an oxygen electrode). Hereinafter referred to the disc made of nickel covered with MnO ₂ in a catalyst "MnO ₂ @Ni".

20 is a view illustrating a MnO ₂ Ni cathode used in a nickel air cell according to an embodiment of the present invention.

In Figure 20, (a) is a scanning electron micrograph of MnO ₂ @Ni cathode, (b) is a graph X- ray diffraction pattern of the MnO ₂ @Ni cathode, (c) the EDS analysis of MnO ₂ cathode @Ni Graph.

Referring to Figure 20, the MnO ₂ is @Ni the MnO ₂ in the flake (flake-like) is disposed on the nickel. The MnO ₂ @ Ni has a nanocrystalline arrangement of tetragonal crystals covered with MnO ₂ formed on the nickel surface as a whole with a ratio of Mn and O of 1: 2. Further, as a result of X-ray diffraction and EDS analysis, no carbon was found. Therefore, the MnO ₂ @ Ni is formed using a hydrothermal method, and does not contain carbon and does not use a binder.

Next, a lithium metal anode, CGPE (mass ratio 2: 8) according to the technical idea of the present invention, a separator composed of glass microfibers, and the MnO ₂ @ Ni cathode were assembled to prepare a Li / CGPE / separator / MnO ₂ Ni A lithium ion battery cell was fabricated.

The CGPE was activated by immersion in a 1 M LiTFSI solution in TEGDME prior to assembling the cell. The separator was formed by immersing the glass microfibers in a 1 M LiTFSI solution in TEGDME.

Unlike the lithium ion polymer battery cell described above, the lithium air cell intentionally further includes the separator separating the CGPE membrane from the MnO ₂ Ni cathode. The reason for this is to increase the chemical stability of the polymer substrate by blocking Li ₂ O ₂ formed on the surface of MnO ₂ catalysts during discharge from PVDF-HFP. For testing, the lithium air cell was placed in a box filled with pure oxygen gas at one atmosphere.

5-2. CGPE  Charge-discharge of a lithium-ion battery cell Cycle  Character analysis

A charge-discharge cycle test was conducted on a lithium air battery cell using CGPE as the electrolyte and a protective layer of lithium metal. The above-described lithium air battery cell was subjected to a charge-discharge cycle test in a constant current mode at a current density of 1000 mAh g ^-1 at a current density of 0.1 mA cm ^-2 . The capacity of the lithium air battery cell was calculated based on the weight of the MnO ₂ catalyst formed on the nickel surface. Also, for comparison, a lithium air battery cell without CGPE was also tested. That is, a lithium air battery cell using CGPE has a structure of lithium / CGPE / separator / cathode, and a lithium air battery cell not using CGPE has a lithium / separator / cathode structure. The separator may comprise a liquid electrolyte and may comprise, for example, the same liquid electrolyte as the liquid electrolyte activating the CGPE.

21 is a graph showing charge-discharge cycle characteristics of a lithium air cell including a composite gel polymer electrolyte according to an embodiment of the present invention.

In Fig. 21, (a) shows a case where CGPE is used as a protective layer of a lithium metal electrode, and (b) shows a case where CGPE is not used.

Referring to FIG. 21 (a), in the case where CGPE is used, it is analyzed that up to 71 charge-discharge cycles can be used when 2 V for discharging and 4.5 V for charging are selected as the allowable potential range.

Referring to FIG. 21 (b), in the case of using CGPE, the discharge potential gradually decreased as the charge-discharge cycle was increased. Judging from the allowable potential range, the discharge potential dropped sharply after 45 charge-discharge cycles and decreased to 2.0 V or less before achieving a capacity of 1000 mAh g ^{- 1} in 48 charge-discharge cycles .

Therefore, it can be seen that the charge-discharge cycle characteristics are greatly improved as compared with the case where CGPE is not included.

The highly improved charge-discharge cycle characteristics realized in lithium air battery cells including CGPE are analyzed by the mixing effect of the high hardness provided by the inorganic A-LLTO / m-SiO ₂ particles and the high viscosity provided by the PVDF-HFP substrate do. In particular, the inclusion of A-LLTO / m-SiO ₂ increased the hardness of the electrolyte and thus effectively suppressed dendritic growth of the lithium metal. In addition, the PVDF-HFP substrate can prevent the diffusion of moisture, impurities and other by-products from the cathode to the anode during the charge-discharge cycle, thereby preventing deterioration of the anode and cathode. In particular, through the surface modification, the SiO ₂ surface of A-LLTO / m-SiO ₂ was functionalized, thereby increasing the ability of the silanol group to contain impurities. As a result, the deterioration of the lithium metal electrode can be prevented, and the long-term stability of the lithium metal battery cell can be greatly improved.

5-3. CGPE  Microstructure Analysis of Lithium Air Battery Cell Including

Even though pure A-LLTO inorganic solid electrolytes are superior in rigidity to CGPE, CGPE has sufficient hardness to inhibit the growth of lithium resin complexes. To demonstrate this, a lithium air battery cell with CGPE and a lithium air battery cell without CGPE were disassembled in a glove box and the microstructure was observed with a scanning electron microscope after performing a charge-discharge cycle test.

22 is a scanning electron micrograph showing the microstructure of a lithium metal electrode included in a lithium air cell including a composite gel polymer electrolyte according to an embodiment of the present invention.

22 (a) and 22 (b) show the case where CGPE is used as the protective layer of the lithium metal electrode, and FIGS. 22 (c) and 22 (d) show the case where CGPE is not used.

Referring to Figures 22 (a) and 22 (b), the lithium metal electrode when using CGPE shows a smooth, flat surface. As indicated by the red arrow, it was confirmed that some lithium resin assumptions were formed. 22 (c) and 22 (d), the lithium metal electrode in the case of not using the CGPE has a porous and coarse structure, although the number of charge-discharge cycles is small, Surface, and a large number of lithium resin assumptions were observed.

Even when CGPE is used, it is difficult to completely prevent occurrence and growth of the lithium resin assumption, because the PVDF-HFP base material is relatively weak. However, unlike the ceramic A-LLTO solid electrolyte, PVDF-HFP substrate can provide flexibility to CGPE and can provide an easy treatment. In addition, CGPE has a sufficient hardness to effectively inhibit the growth of the lithium resin phase and has a high ion conductivity capable of excellent battery cell operation.

conclusion

CGPE according to the technical idea of the present invention can be produced by a simple solution casting method and can be produced by activating a liquid electrolyte. The CGPE is composed of PVDF-HFP substrate comprising a A-LLTO particles covered with the m-SiO ₂ layer.

Manufactured CGPE is 1.22 X 10 ^-3 S cm compared to pure GPE ^- with respect to ^one of the higher ion conductivity, Li / Li ⁺ has a broad electrochemical stability range, and interface stability of up to 5 V.

The use of CGPE in lithium metal-based batteries shows the following applicability. (i) it is used as an electrolyte in a lithium ion polymer battery and can provide high stability. (ii) It is used as a protective layer against the lithium metal anode in a lithium air cell, and can transmit high energy.

The charge-discharge cycle results for the Li / Li symmetric battery cells and the microstructure results of the lithium surface indicate that the lithium cell phase positive growth can be effectively suppressed by using CGPE in the battery cell.

A Li-LiCoO ₂ polymer battery cell containing CGPE provides 80.5% capacity retention after 500 charge-discharge cycles at 0.5 C, which is almost three times higher than without CGPE.

Lithium air battery cells containing CGPE as a protective layer exhibit 72 cycles life in a limited capacity mode of 1000 mAh, which is higher than in the absence of CGPE exhibiting 25 cycles.

The improved properties of lithium-based battery cells including CGPE are due to the effective inhibition of the growth of lithium resin implants and can prevent the decomposition of the electrolyte and also reduce the oxygen gas And the diffusion of contaminants can be prevented.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. Will be apparent to those of ordinary skill in the art.

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Claims (20)

Polymer substrates; And
A core-shell structure consisting of a core portion dispersed in the polymer substrate and having ion conductivity therein, and a shell portion covering a surface of the core material;
≪ / RTI > The method according to claim 1,
Wherein the polymer substrate comprises at least one of polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP), polyvinylidene fluoride (PVDF) and polymethylmethacrylate (PMMA), the composite gel polymer electrolyte membrane . Wherein the core portion has a perovskite structure. The method according to claim 1,
The core portion may include aluminum-doped lithium lanthanum titanate (A-LLTO), lithium aluminum germanium phosphate (LAGP), and lithium aluminum titanium phosphate (LATP ). ≪ / RTI > The method according to claim 1,
Said core portion _{(Li 0. 33 La 0.} 56) 1.005 Ti 0. ₉₉ Al _{0 . 01} O ₃ , and Li _{1 . 5} Al _{0 . 5} Ge _{1 .5} (PO ₄ ) ₃ , and Li _1.5 Al _0.5 Ti _1.5 (PO ₄ ) ₃ . The method according to claim 1,
Wherein the shell portion comprises an amorphous phase. The method according to claim 1,
Wherein the shell portion comprises at least one of silicon oxide, silicon nitride, silicon oxynitride, zirconium oxide, zirconium nitride, zirconium oxynitride, and aluminum oxide. The method according to claim 1,
It said shell portion m-SiO ₂ having an oxygen atom to provide a binding site ≪ / RTI > 9. The method of claim 8,
The m-SiO ₂ Is controlled by using 3-glycidoxypropyl trimethoxysilane (GPTMS). The thickness of the membrane is controlled by using 3-glycidoxypropyl trimethoxysilane (GPTMS). 9. The method of claim 8,
Wherein at least one of hydroxyl group (OH ^- ) and epoxy group is formed in the shell part. The method according to claim 1,
Wherein the core-shell structure has a size ranging from 0.5 [mu] m to 3 [mu] m. The method according to claim 1,
Wherein the shell portion has a thickness in the range of 1 nm to 10 < RTI ID = 0.0 > nm. ≪ / RTI > The method according to claim 1,
Wherein the polymer substrate and the core-shell structure have a mass ratio in the range of 8: 2 to 2: 8. The method according to claim 1,
Wherein the core-shell structure is uniformly distributed within the polymer substrate. The method according to claim 1,
Wherein the core-shell structure inhibits the resinous growth of the lithium metal. The method according to claim 1,
Wherein the composite gel polymer electrolyte membrane is activated using a liquid electrolyte in which LiPF ₆ is mixed with a solution of ethylene carbonate and ethyl methyl carbonate. The method according to claim 1,
The composite gel polymer electrolyte membrane is prepared by mixing a liquid electrolyte prepared by mixing lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) with a tetraethylene glycol dimethyl ether (TEGDME) solution ≪ / RTI > Preparing an aluminum-doped lithium lanthanum titanate (A-LLTO) powder;
Mixing a solution of the aluminum-doped lithium lanthanum titanate in ethanol with a solution of polyvinylpyrrolidone in deionized water to form a first mixed solution;
Separating the supernatant by centrifuging the first mixed solution to form a surfactant-stabilized A-LLTO;
Mixing the supernatant stabilized A-LLTO with ethanol, deionized water, and ammonia water to form a suspension solution;
Adding ethanol containing tetraisosilane to the suspension solution to form a second mixed solution; And
Centrifuging the second mixed solution to form A-LLTO / m-SiO ₂ particles;
≪ / RTI > Anode;
Cathode; And
A polymer substrate interposed between the anode and the cathode; And a core-shell structure comprising a core portion dispersed in the polymer substrate and having ion conductivity therein, and a shell portion covering a surface of the core material, the composite gel polymer electrolyte comprising:
≪ / RTI > Anode;
Cathode; And
A polymer substrate interposed between the anode and the cathode; And a core-shell structure comprising a core portion dispersed in the polymer substrate and having ion conductivity therein, and a shell portion covering a surface of the core material, the composite gel polymer electrolyte comprising:
/ RTI > air battery.

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