KR20140139292A - Separator and electrochemical device having the same - Google Patents

Abstract

The present invention relates to a separator and an electrochemical device having the same. The separator includes two porous members which face each other; and a porous coating layer which is interposed between the two porous members and includes the mixture of a binder polymer and inorganic particles. An organic-inorganic porous coating layer of enough thickness can be formed to secure enough safety of an electrochemical device by interposing an organic-inorganic porous coating layer between the porous members which face each other. Also, because the organic-inorganic porous coating layer is surrounded by a porous member, there is no problem of organic particle secession. Because the use of a polymer binder for fixing organic particles is reduced, an increase in resistance due to the binder polymer can be prevented.

Description

SEPARATOR AND ELECTROCHEMICAL DEVICE HAVING THE SAME Technical Field [1] The present invention relates to a separator,

To a separator of an electrochemical device such as a lithium secondary battery and an electrochemical device having the separator. More particularly, the present invention relates to a separator having a porous coating layer including an organic-inorganic mixture interposed between two porous substrates facing each other, And an electrochemical device having the same.

Recently, interest in energy storage technology is increasing. As the application fields of cell phones, camcorders, notebook PCs and even electric vehicles are expanding, efforts for research and development of electrochemical devices are becoming more and more specified. Electrochemical devices have attracted the greatest attention in this respect, among which the development of rechargeable secondary batteries has become a focus of attention. In recent years, in order to improve the capacity density and specific energy in developing such batteries, And research and development on the design of the battery.

Among the currently applied secondary batteries, the lithium secondary battery developed in the early 1990s has advantages such as higher operating voltage and higher energy density than conventional batteries such as Ni-MH, Ni-Cd and sulfuric acid-lead batteries using an aqueous electrolyte solution . However, such a lithium ion battery has safety problems such as ignition and explosion when using an organic electrolytic solution, and it is disadvantageous in that it is difficult to manufacture. Recently, the lithium ion polymer battery is considered to be one of the next generation batteries by improving the weak point of the lithium ion battery. However, since the capacity of the battery is still relatively low as compared with the lithium ion battery, Is urgently required.

Such electrochemical devices are produced in many companies, but their safety characteristics are different. It is very important to evaluate the safety and safety of such an electrochemical device. The most important consideration is that the electrochemical device should not injure the user in case of malfunction. For this purpose, the safety standard strictly regulates the ignition and fuming in the electrochemical device. In the safety characteristics of the electrochemical device, there is a high possibility that the electrochemical device will be overheated to cause thermal runaway or explosion if the separator is penetrated. Particularly, the polyolefin-based porous substrate commonly used as a separator of an electrochemical device exhibits extreme heat shrinkage behavior at a temperature of 100 DEG C or higher owing to the characteristics of the manufacturing process including material properties and elongation, . ≪ / RTI >

In order to solve the safety problem of such an electrochemical device, a separator has been proposed in which an organic-inorganic porous coating layer is formed by coating a mixture of an excess of inorganic particles and a binder polymer on at least one surface of a porous substrate having a plurality of pores. However, in the case of forming the organic-inorganic porous coating layer on the outer surface of the porous substrate, the thickness of the organic-inorganic porous coating layer formed on the outer surface is limited due to the thin thickness of the porous substrate, .

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a separator which does not limit the thickness of the organic-inorganic porous coating layer and an electrochemical device using the same, in order to enhance the safety of the electrochemical device.

In order to solve the above-mentioned problems, there are two porous substrates facing each other; And a porous coating layer interposed between the two porous substrates, the porous coating layer including a mixture of binder polymer and inorganic particles.

The separator of the present invention may further comprise an electrode bonding layer formed on at least one surface of the outermost surface.

The type of the porous substrate is not particularly limited, but a polyolefin-based porous substrate can be used. As the polyolefin-based porous substrate, polyethylene, polypropylene, polybutylene, and polypentene are preferably used.

As the inorganic particles of the present invention, inorganic particles having a dielectric constant of 5 or more, inorganic particles having lithium ion transferring ability, and mixtures thereof can be used.

The inorganic particles having a dielectric constant of not less than 5 are not particularly limited, and BaTiO ₃ , Pb (Zr _x , Ti _1-x ) O ₃ (PZT, 0 <x <1), Pb _1-x La _x (1-x) Pb (Mg _1/3 Nb _2/3 ) O ₃ -xPbTiO ₃ (PMN-PT, Zr _1-y Ti _y O ₃ (PLZT, 0 <x < SiO ₂ , Y ₂ O ₃ , Al ₂ O ₃ , SiC, and TiO ₂ (0 <x <1), HfO ₂ , SrTiO ₃ , SnO ₂ , CeO ₂ , MgO, NiO, CaO, ZnO, ZrO ₂ , ₂ , or a mixture of two or more of these inorganic particles.

As the inorganic particles having lithium ion transferring ability, lithium phosphate (Li ₃ PO ₄ ), lithium titanium phosphate (Li _x Ti _y (PO ₄ ) ₃ , 0 <x <2, 0 <y < (Li _x Al _y Ti _z (PO ₄ ) ₃ , 0 <x <2, 0 <y <1, 0 <z <3), (LiAlTiP) _x O _y series glass 0 <y <13), lithium lanthanum titanate (Li _x La _y TiO ₃ , 0 <x <2, 0 <y <3), lithium germanium thiophosphate (Li _x Ge _y P _z S _w , x <4, 0 <y < 1, 0 <z <1, 0 <w <5), lithium nitrides _{(Li x N y, 0 <} x <4, 0 <y <2), SiS 2 (Li x _{Si y S z, 0 <x} <3, 0 <y <2, 0 <z <4) based glass, and _{P 2 S 5 (Li x P} y S z, 0 <x <3, 0 <y <3, 0 < z < 7) series glass, or a mixture of two or more of them, but the present invention is not limited thereto.

The binder polymer of the present invention is not particularly limited, but examples of the binder polymer include polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride, Polyvinylidene fluoride-co-trichlorethylene, polymethylmethacrylate, polybutylacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate polyvinyl acetate, polyvinylacetate, polyvinyl alchol, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyl Cellulose acetate butyrate, cellulose acetic acid But are not limited to, cellulose acetate propionate, cyanoethylpullulan, cyanoethylpolyvinylalcohol, cyanoethylcellulose, cyanoethylsucrose, pullulan, , Carboxyl methyl cellulose, and a low molecular weight compound having a molecular weight of 10,000 g / mol or less.

The separator of the present invention can be applied to a separator of an electrochemical device such as a lithium secondary electron or a supercapacitor.

An organic-inorganic porous coating layer having a sufficient thickness may be formed to secure sufficient safety of the electrochemical device through the organic-inorganic porous coating layer between the porous substrates facing each other according to the present invention. In addition, since the organic-inorganic porous coating layer is wrapped with the porous substrate, there is no fear of separation of the inorganic particles, and the use of the polymer binder for fixing the inorganic particles can be reduced, so that the increase in resistance due to the binder polymer can be prevented. In addition, it is possible to prevent the problem that the separator is mechanically damaged due to foreign matters during the manufacturing process of the electrochemical device to cause defects, and as a result, the rigidity of the separator can be increased and the safety can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments of the invention and, together with the description of the invention, It should not be construed as limited.
1 is a cross-sectional view of a separator having an organic-inorganic porous coating layer according to a preferred embodiment of the present invention.
2 is a cross-sectional view of a separator having an organic-inorganic porous coating layer and an electrode adhesive layer according to a preferred embodiment of the present invention.
3 is a graph showing the thermal stability test results of the separator according to Examples and Comparative Examples.
4 is a schematic view showing a ball crush test method of the separator according to the embodiment and the comparative example.
5 is a graph showing the results of the ball crush test of the separator according to Examples and Comparative Examples.

Hereinafter, the present invention will be described in detail with reference to the drawings. The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

FIG. 1 schematically shows an embodiment of a separator having a porous coating layer comprising a mixture of a binder polymer and inorganic particles according to the present invention. It should be noted, however, that the embodiments shown in the following description and the configurations shown in the drawings are only the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It should be understood that various equivalents and modifications may be present.

Referring to FIG. 1, the separator 100 of the present invention includes two porous substrates 110 and 110 'facing each other; And a porous coating layer 120 interposed between the two porous substrates 110 and 110 'and including a mixture of binder polymer and inorganic particles.

A porous coating layer 120 made of a mixture of inorganic particles and a binder polymer is formed between the two porous substrates 110 and 110 'facing each other. The porous coating layer 120 is formed by applying a slurry containing a mixture of inorganic particles and a binder polymer to one surface of one porous substrate 110, followed by drying. The separator 100 of the present invention can be manufactured by attaching another porous substrate 110 'to the formed porous coating layer 120.

In this porous coating layer 120, the binder polymer adheres to each other (that is, the binder polymer binds and fixes the inorganic particles) so that the inorganic particles can remain bonded to each other, and the porous coating layer 120 is bonded to the binder polymer And is adhered to another porous substrate 110 '. The inorganic particles of the porous coating layer 120 are present in a closely packed state in a state of being substantially in contact with each other. The interstitial volume generated when the inorganic particles are in contact with each other becomes the pores of the porous coating layer 120. The separator 100 having the porous coating layer 120 formed thereon is excellent in heat resistance, thereby enhancing safety. The thickness of the porous coating layer 120 is preferably 1 to 20 占 퐉.

In the separator 100 of the present invention, the porous coating layer 120 is interposed between the porous substrates 110 and 110 ', and the porous coating layer 120 is surrounded by the porous substrates 110 and 110' The separation of the inorganic particles from the porous coating layer 120 can be prevented from occurring. In addition, since the use of the polymer binder for fixing the inorganic particles can be reduced owing to the morphological feature, the increase of the resistance due to the binder polymer can be prevented.

As the porous substrate, any porous substrate commonly used in an electrochemical device may be used. For example, a polyolefin porous substrate or a non-polyolefin porous substrate may be used, but the present invention is not limited thereto.

Examples of the polyolefin-based porous substrate include polymers such as high-density polyethylene, linear low density polyethylene, low density polyethylene, ultra high molecular weight polyethylene, polyethylene, polypropylene, polybutylene and polypentene, And the form thereof may be a film or a nonwoven fabric.

Examples of the non-polyolefin-based porous substrate include polyolefin resins such as polyethylene terephthalate, polybutylene terephthalate, polyester, polyacetal, polyamide, polycarbonate polycarbonate, polyimide, polyetheretherketone, polyethersulfone, polyphenylene oxide, polyphenylenesulfrode, and polyethylenenaphthalene, which are used alone or in combination. Or a film or a nonwoven fabric formed of a polymer mixed with these.

At this time, the structure of the nonwoven fabric may be a spun bond nonwoven fabric or a melt blown nonwoven fabric composed of long fibers.

The thickness of the porous substrate is not particularly limited, but may be 5 to 50 탆, and the pore size and porosity present in the porous substrate are also not particularly limited, but may be 0.01 to 50 탆 and 10 to 95%, respectively.

The inorganic particles used in the present invention are not particularly limited as long as they are electrochemically stable. That is, the inorganic particles usable in the present invention are not particularly limited as long as oxidation and / or reduction reaction does not occur in the operating voltage range of the applied electrochemical device (for example, 0 to 5 V based on Li / Li ⁺ ). Particularly, when inorganic particles having a high dielectric constant are used as the inorganic particles, the dissociation of the electrolyte salt, for example, the lithium salt in the liquid electrolyte, can be increased, and the ion conductivity of the electrolyte can be improved.

For the reasons stated above, it is preferable that the inorganic particles include high-permittivity inorganic particles having a dielectric constant of 5 or more, preferably 10 or more. Nonlimiting examples of inorganic particles having a dielectric constant of 5 or more include BaTiO ₃ , Pb (Zr _x , Ti _1-x ) O ₃ (PZT, 0 <x <1), Pb _{1 -x} La _x Zr _{1 -y} Ti _y (PMN-PT, 0 < x < 1) O ₃ (PLZT, 0 <x <1, 0 <y <1), (1-x) Pb (Mg _1/3 Nb _2/3 ) O ₃ -xPbTiO ₃ , Hafnia (HfO ₂ ), SrTiO ₃ , SnO ₂ , CeO ₂ , MgO, NiO, CaO, ZnO, ZrO ₂ , Y ₂ O ₃ , Al ₂ O ₃ , TiO _2, SiC Or a mixture thereof.

As the inorganic particles, inorganic particles having a lithium ion transferring ability, that is, inorganic particles containing a lithium element but having a function of transferring lithium ions without storing lithium can be used. Non-limiting examples of inorganic particles having lithium ion transferring ability include lithium phosphate (Li ₃ PO ₄ ), lithium titanium phosphate (Li _x Ti _y (PO ₄ ) ₃ , 0 <x <2, 0 <y < (Li _x Al _y Ti _z (PO ₄ ) ₃ , 0 <x <2, 0 <y <1, 0 <z <3), 14Li ₂ O-9Al ₂ O ₃ -38TiO ₂ -39P ₂ O _5, including (LiAlTiP) _x O _y series glass (0 <x <4, 0 <y <13), lithium lanthanum titanate _{(Li x La y TiO 3,} 0 <x <2, 0 <y <3) (Li _x Ge _y P _z S _w , 0 <x <4, 0 <y <1, 0 <z <1, 0 <w <5) such as Li _3.25 Ge _0.25 P _0.75 S ₄ ), Li ₃ lithium nitride such as _{N (Li x N y, 0} <x <4, 0 <y <2), Li 3 PO 4 SiS 2 family, such as _{-Li 2 S-SiS 2 glass (} Li x Si _{y S z, 0 <x <} 3, 0 <y <2, 0 <z <4), LiI-Li 2 SP 2 S 5 , etc., such as P ₂ S ₅ based _{glass (Li x P y S z} , 0 <x <3, 0 <y <3, 0 <z <7), or a mixture thereof.

The binder polymer is preferably a polymer having a glass transition temperature (T _g ) of -200 to 200 ° C because it can improve mechanical properties such as flexibility and elasticity of the coating layer finally formed to be.

In addition, the binder polymer does not necessarily have ion conductivity, but the performance of the electrochemical device can be further improved by using a polymer having ion conductivity. Therefore, it is preferable that the binder polymer has a high permittivity constant. In fact, since the dissociation degree of the salt in the electrolyte depends on the permittivity constant of the electrolyte solvent, the higher the permittivity constant of the binder polymer, the better the salt dissociation in the electrolyte. The dielectric constant of such a binder polymer may be in the range of 1.0 to 100 (measurement frequency = 1 kHz), preferably 10 or more.

In addition to the functions described above, the binder polymer may be characterized by being capable of exhibiting a high degree of swelling of the electrolyte by being gelled upon impregnation with a liquid electrolyte. Accordingly, it is preferable to use a polymer having a solubility index of 15 to 45 MPa ^1/2 , more preferably a solubility index of 15 to 25 MPa ^1/2 and a range of 30 to 45 MPa ^1/2 . Therefore, it is preferable to use hydrophilic polymers having many polar groups, rather than hydrophobic polymers such as polyolefins. If the solubility index is less than 15 MPa &lt; ^1/2 &gt; and more than 45 MPa &lt; ^1/2 &gt;, it is difficult to swell by a conventional liquid electrolyte for a battery.

Non-limiting examples of such a binder polymer include polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichlorethylene, polymethylmethacrylate, But are not limited to, polymethylmethacrylate, polybutylacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinylacetate, polyvinyl alchol, ethylene vinyl acetate copolymer polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, , Cyanoethylaniline cyanoethylpolyvinylalcohol, cyanoethylcellulose, cyanoethylsucrose, pullulan, carboxyl methyl cellulose, and a molecular weight of 10,000 g / mol And the following low-molecular compounds.

The weight ratio of the inorganic particles to the binder polymer may be 50:50 to 99: 1, or 60:40 to 90:10, or 70:30 to 80:20.

The thickness of the porous coating layer composed of the inorganic particles and the binder polymer is not particularly limited, but may be in the range of 0.01 to 20 占 퐉. The pore size and porosity are also not particularly limited, but the pore size may be in the range of 0.01 to 10 mu m, and the porosity may be in the range of 5 to 90%.

The separator according to an aspect of the present invention may further include other additives in addition to the inorganic particles and the binder polymer as the porous coating layer component.

The porous coating layer 120 is formed by preparing a slurry of a mixture of inorganic particles and a binder polymer using a solvent, applying the slurry on one side of the porous substrate, and drying the mixture. The solvent used herein is a binder polymer to be used and a solubility index , And it is preferable that the boiling point is low. This is to facilitate uniform mixing and subsequent solvent removal. Non-limiting examples of usable solvents include acetone, tetrahydrofuran, methylene chloride, chloroform, dimethylformamide, N-methyl-2-pyrrolidone ( N-methyl-2-pyrrolidone, NMP), cyclohexane, water or a mixture thereof.

After the porous coating layer is formed on one side of the porous substrate as described above, another porous substrate is attached to the porous coating layer to finally produce the separator. At this time, the method of attaching the other porous substrate can be applied without particular limitation, provided that it does not affect the pore characteristics of the porous coating layer and the adhesion force between the porous substrate and the porous coating layer already attached. Examples of a method of attaching such another porous substrate include a thermal compression bonding method and the like.

The separator having the functional multilayer of the present invention can be interposed between the positive electrode and the negative electrode as in the conventional separator. In this case, the porous coating layer made of an inorganic material prevents a short circuit between the positive electrode and the negative electrode even in the case of overheating.

Further, the separator according to an embodiment of the present invention may further include an electrode adhesive layer formed on at least one surface of the outermost surface.

Referring to FIG. 2, a separator 200 according to an embodiment of the present invention includes two porous substrates 210 and 210 'facing each other; A porous coating layer (220) interposed between the two porous substrates (210, 210 ') and comprising a mixture of binder polymer and inorganic particles; And electrode bonding layers 230 and 230 'formed on the porous coating layer 220.

The electrode adhesive layer includes a polymer for an adhesive layer, wherein the polymer for the adhesive layer may be one selected from the above-mentioned binder polymers or a mixture of two or more thereof.

The electrochemical device of the present invention includes all devices that perform an electrochemical reaction, and specific examples thereof include capacitors such as all kinds of primary, secondary cells, fuel cells, solar cells, and super capacitors . Particularly, a lithium secondary battery including a lithium metal secondary battery, a lithium ion secondary battery, a lithium polymer secondary battery, or a lithium ion polymer secondary battery is preferable.

In the electrochemical device of the present invention, an electrolyte in which a salt having a structure such as A ⁺ B ^- is dissolved in an organic solvent can be selectively used. Wherein, A ⁺ is Li ^+, Na ^+, and comprising an alkali metal cation or an ion composed of a combination thereof, such as K ^+, B ^- is _{^{PF 6 -, BF 4 -,}} Cl -, Br -, I -, ClO Anions such as ₄ ^- , AsF ₆ ^- , CH ₃ CO ₂ ^- , CF ₃ SO ₃ ^- , N (CF ₃ SO ₂ ) ₂ ^- and C (CF ₂ SO ₂ ) ₃ ^- do. Examples of the organic solvent include propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), dimethyl sulfoxide, acetonitrile, dimethoxyethane, But are not limited to, tetrahydrofuran, N-methyl-2-pyrrolidone (NMP), ethylmethyl carbonate (EMC), gamma-butyrolactone no.

The electrolyte may be injected at an appropriate stage of the battery manufacturing process, depending on the manufacturing process and required properties of the final product. That is, it can be applied before assembling the cell or at the final stage of assembling the cell.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to examples. However, the embodiments according to the present invention can be modified into various other forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. The embodiments of the present invention are provided to enable those skilled in the art to more fully understand the present invention.

Example: Preparation of a separator having an organic-inorganic porous coating layer interposed between two porous substrates

PVdF-CTFE (polyvinylidene fluoride-chlorotrifluoroethylene copolymer) was added to acetone in a weight ratio of about 5 wt% and dissolved at 50 DEG C for about 12 hours or longer to prepare a polymer solution. Al ₂ O ₃ powder and BaTiO ₃ powder were added to the prepared polymer solution so that the weight ratio of polymer / inorganic powder = 20/80 was added at a weight ratio of 9: 1, and the resultant mixture was subjected to ball milling for 12 hours or longer, The powder was crushed and dispersed into a size of 300 nm to prepare a slurry.

The slurry thus prepared was coated on a polyethylene porous substrate (porosity of 40%) having a thickness of 20 占 퐉 by a dip coating method to form a porous coating layer. The thickness of the porous coating layer was adjusted to about 2 탆. Then, a polyethylene porous substrate (porosity of 40%) having a thickness of 20 탆 was attached to the top of the porous coating layer by a thermocompression bonding method.

Comparative Example. Preparation of a separator having an organic-inorganic porous coating layer formed on both surfaces of a porous substrate

PVdF-CTFE (polyvinylidene fluoride-chlorotrifluoroethylene copolymer) was added to acetone in a weight ratio of about 5 wt% and dissolved at 50 DEG C for about 12 hours or longer to prepare a polymer solution. Al ₂ O ₃ powder and BaTiO ₃ powder were added to the prepared polymer solution so that the weight ratio of polymer / inorganic powder = 20/80 was added at a weight ratio of 9: 1, and the resultant mixture was subjected to ball milling for 12 hours or longer, The powder was crushed and dispersed into a size of 300 nm to prepare a slurry.

The slurry thus prepared was coated on a polyethylene porous substrate (porosity of 40%) having a thickness of 20 占 퐉 by a dip coating method to form a porous coating layer. The thickness of the porous coating layer was adjusted to about 2 탆. Thereafter, a porous coating layer was formed on the other surface of the polyethylene porous substrate on which the porous coating layer was not formed, in the same manner as described above.

Test Example 1. Evaluation of thermal stability (confirmation of degree of shrinkage upon heating)

The separators prepared in Examples and Comparative Examples were cut into 5 cm in the MD direction (transverse direction) and 5 cm in the TD direction (longitudinal direction), and then stored in an oven at 150 ° C for 30 minutes. The measurement results are shown in Fig.

Test Example 2. Ball crush test (w / Fe powder)

After a suitable amount of Fe powder was applied onto the separator prepared in Examples and Comparative Examples, a layer of Fe powder having a thickness of 5 탆 was passed through a gap of 5 탆 in thickness, and pressed at a pressure higher or lower. (See Fig. 4)

The pressure at which an electrical short occurs is measured. The evaluation results of the separator prepared in Examples and Comparative Examples are shown in Fig.

100, 200: Separator
110, 110 ', 210, 210': Porous substrate 120, 220: Porous coating layer
230, 230 ': electrode bonding layer

Claims (10)

Two porous substrates facing each other; And
And a porous coating layer interposed between the two porous substrates, the porous coating layer comprising a mixture of binder polymer and inorganic particles. The method according to claim 1,
And an electrode bonding layer formed on at least one surface of the outermost surface of the separator. The method according to claim 1,
Wherein the porous substrate is a polyolefin-based porous substrate. The method of claim 3,
Wherein the polyolefin-based porous substrate is formed of any one selected from the group consisting of polyethylene, polypropylene, polybutylene, and polypentene. The method according to claim 1,
Wherein the inorganic particles are inorganic particles selected from the group consisting of inorganic particles having a dielectric constant of 5 or more, inorganic particles having lithium ion transporting ability, and mixtures thereof. 6. The method of claim 5,
The inorganic particles having a dielectric constant of 5 or more include BaTiO ₃ , Pb (Zr _x , Ti _{1 -x} ) O ₃ (PZT, 0 <x <1), Pb _{1 -x} La _x Zr _{1 -y} Ti _y O ₃ , 0 <x <1, 0 <y <1), (1-x) Pb (Mg _1/3 Nb _2/3 ) O ₃ -xPbTiO ₃ (PMN- HfO ₂ ), SrTiO ₃ , SnO ₂ , CeO ₂ , MgO, NiO, CaO, ZnO, ZrO ₂ , SiO ₂ , Y ₂ O ₃ , Al ₂ O ₃ , SiC and TiO ₂ Particles or a mixture of two or more thereof. 6. The method of claim 5,
The inorganic particles having lithium ion transferring ability include lithium phosphate (Li ₃ PO ₄ ), lithium titanium phosphate (Li _x Ti _y (PO ₄ ) ₃ , 0 <x <2, 0 <y <3), lithium aluminum titanium phosphate (Li _x Al _y Ti _z (PO ₄ ) ₃ , 0 <x <2, 0 <y <1, 0 <z <3), (LiAlTiP) _x O _y series glass <13), lithium lanthanum titanate (Li _x La _y TiO ₃ , 0 <x <2, 0 <y <3), lithium germanium thiophosphate (Li _x Ge _y P _z S _w , , 0 <y <1, 0 <z <1, 0 <w <5), lithium nitrides _{(Li x N y, 0 <} x <4, 0 <y <2), SiS 2 (Li x Si y S _{z, 0 <x <3,} 0 <y <2, 0 <z <4) based glass, and _{P 2 S 5 (Li x P} y S z, 0 <x <3, 0 <y <3, 0 <z &Lt; 7) series glass, or a mixture of two or more thereof. The method according to claim 1,
The binder polymer may be at least one selected from the group consisting of polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichlorethylene, polymethylmethacrylate, But are not limited to, polybutyl acrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinylacetate, polyvinyl alchol, polyethylene-co- polyvinyl acetate, vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, Cyanoethylpullulan, cyanoethyl It is made up of cyanoethylpolyvinylalcohol, cyanoethylcellulose, cyanoethylsucrose, pullulan, carboxyl methyl cellulose and a low molecular weight compound with a molecular weight of 10,000 g / mol or less Or a mixture of two or more of them. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt; An electrochemical device comprising a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode,
The electrochemical device according to any one of claims 1 to 8, wherein the separator is a separator. 10. The method of claim 9,
Wherein the electrochemical device is a lithium secondary battery.

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