KR20180124546A - Polymer solid electrolyte composition and polymer membrane comprising the same - Google Patents

Abstract

The present invention relates to polymer solid electrolyte having high ionic conductivity. By using the polymer solid electrolyte, a lithium secondary battery having improved performance and enhanced safety may be provided. A polymer solid electrolyte composition comprises: an ion supply compound; a block polymer having a phase separated structure; and an oxidizing agent.

Description

TECHNICAL FIELD The present invention relates to a polymer solid electrolyte composition and a polymer membrane comprising the polymer electrolyte membrane.

The present invention relates to a polymer solid electrolyte composition and a polymer membrane containing the same.

Lithium secondary batteries are used in a variety of industries such as smart phones and notebooks, as well as small electronic devices and automotive batteries. They are being developed in the technical direction of miniaturization, weight reduction, high performance, and high capacity.

The lithium secondary battery includes a cathode, an anode, and an electrolyte. As the cathode active material of the lithium secondary battery, lithium, carbon, or the like is used. As the cathode active material, a transition metal oxide, a metal chalcogen compound, a conductive polymer, or the like is used, and a liquid electrolyte, a solid electrolyte and a polymer electrolyte are used as an electrolyte have.

Among them, the polymer electrolyte is environment-friendly because there is no problem such as leakage of the liquid generated in the liquid electrolyte, and it is possible to make thin film and film type processing, so that it is easy to change the structure of the device in any desired form.

The polymer electrolyte is composed of a polymer, a lithium salt, a non-aqueous organic solvent (optional), and other additives. The polymer electrolyte is excellent in ionic conductivity, but has a problem that performance is lowered than that of a nonaqueous liquid electrolyte.

To overcome this problem, it is necessary to develop an ion conductive polymer electrolyte having high ionic conductivity at room temperature.

Korean Patent Publication No. 10-2013-001176 (2013.01.30)) A block copolymer comprising a hydrophilic block and a hydrophobic block, a polymer electrolyte membrane containing the same and a fuel cell

In order to solve the above problems, the present inventors have conducted various studies to develop a polymer solid electrolyte having a new composition. As a result, they have found that a block polymer having a phase-separated structure is mixed with an ion- As a result, it was confirmed that the lithium ion secondary battery has a high ion conductivity and the performance and safety of the lithium secondary battery can be improved. Thus, the present invention has been completed.

Accordingly, an object of the present invention is to provide a polymer solid electrolyte composition for producing a polymer solid electrolyte.

The present invention also provides a polymer membrane made of the polymer solid electrolyte composition.

The present invention also provides a lithium secondary battery comprising a polymer membrane made of the polymer solid electrolyte composition.

In order to achieve the above object, the present invention provides an ion-supplying compound; A block polymer having a phase-separated structure; And a polymer solid electrolyte composition comprising an oxidizing agent.

The present invention also provides a polymer membrane made of the polymer solid electrolyte composition.

The present invention also provides a lithium secondary battery comprising the polymer membrane.

The polymer solid electrolyte composition according to the present invention secures a high ionic conductivity and improves the stability of a lithium secondary battery.

1 is a sectional view showing a lithium secondary battery according to the present invention.

In the present invention, a polymer solid electrolyte composition comprising a block polymer having a phase-separated structure and having improved ionic conductivity is prepared, and a technique for applying the polymer solid electrolyte composition to a lithium secondary battery is presented.

Polymer solid electrolyte composition

The polymer solid electrolyte composition according to the present invention comprises an ion-supplying compound; A block polymer having a phase-separated structure; And an oxidizing agent.

The ion supplying compound used for preparing the polymer solid electrolyte composition of the present invention can improve the lithium ion conductivity, and according to one embodiment of the present invention, the ion supplying compound may be a lithium salt.

Examples of the lithium salt include LiCl, LiBr, LiI, LiClO ₄ , LiBF ₄ , LiB ₁₀ Cl ₁₀ , LiPF ₆ , LiAsF ₆ , LiSbF ₆ , LiAlCl ₄ , LiSCN, Li (FSO ₂ ) ₂ N LiCF ₃ CO ₂ , LiCH ₃ SO ₃ , LiCF ₃ SO ₃ , LiN (SO ₂ CF ₃ ) ₂ , LiTFSI, LiFSI, LiOH, LiOHH ₂ O, LiBOB, LiN (SO ₂ C ₂ F ₅ ) ₂ , LiC ₄ F ₉ SO _{3 , LiC (CF 3 SO 2)} 3, (CF 3 SO 2) 2 NLi, LiOH.H 2 O, LiB (C 2 O 4) 2, chloroborane lithium, lower aliphatic carboxylic acid lithium, lithium tetraphenyl borate, lithium A lithium salt selected from the group consisting of imides and combinations thereof, and the like can be used.

Preferably, the ion-supplying compound is contained in an amount of 10 to 30% by weight, preferably 15 to 25% by weight, in the whole polymer solid electrolyte. If the content of the ion supplying compound is less than the above range, it is not easy to ensure the lithium ion conductivity. On the other hand, when the content exceeds the above range, the effect is not greatly increased, which is uneconomical.

The polymer solid electrolyte composition of the present invention may include a block polymer having a phase-separated structure. The block is a block made of a plurality of constituent units as a part of molecules contained in the polymer and different in chemical structure or steric configuration from the other parts in contact with the block.

The block polymer having the phase-separated structure is specifically a block polymer having a fine phase separation. The block polymer can form a nanostructure through fine phase separation, and the ionic conductivity can be improved by such a structural feature.

The first block of the fine phase-separated block polymer may be a block represented by the following Formula 1 in one example.

[Chemical Formula 1]

Wherein R is hydrogen or an alkyl group having 1 to 4 carbon atoms and X is a single bond, an oxygen atom, a sulfur atom, -S (= O) ₂ -, a carbonyl group, an alkylene group, an alkenylene group, (= O) -X ₁ - or -X ₁ -C (= O) -, wherein X ₁ represents an oxygen atom, a sulfur atom, -S (= O) ₂ -, an alkylene group, And Y is a monovalent substituent group comprising a ring structure having a chain having at least 8 chain-forming atoms linked thereto.

The term " single bond " as used in the present application means that no separate atom is present at that site. For example, when X in the general formula (1) is a single bond, a structure in which Y is directly connected to a polymer chain can be realized.

The term "alkyl group" as used herein, unless otherwise specified, includes straight chain, branched or cyclic alkyl groups having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, (Provided that when the above-mentioned side chain is an alkyl group, the alkyl group may have 8 or more, 9 or more, 10 or more, 11 or more And the number of carbon atoms of the alkyl group may be 30 or less, 25 or less, 20 or less, or 16 or less).

Unless otherwise specified, the term "alkenyl group" or "alkynyl group" as used herein refers to a straight chain alkyl group having 2 to 20 carbon atoms, 2 to 16 carbon atoms, 2 to 12 carbon atoms, 2 to 8 carbon atoms, Branched or cyclic alkenyl or alkynyl group, which may optionally be substituted with one or more substituents (provided that the above-mentioned alkenyl or alkynyl group as the side chain is at least 8, at least 9 , 10 or more, 11 or more, or 12 or more carbon atoms, and the number of carbon atoms of the alkenyl group or alkynyl group may be 30 or less, 25 or less, 20 or less, or 16 or less ).

The term " alkylene group ", as used herein, unless otherwise specified, includes a straight, branched or cyclic alkyl group having 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, Lt; / RTI > alkylene group, which may optionally be substituted by one or more substituents.

In the above formula (1), X may be -C (= O) O- or -OC (= O) - in another example.

In the above formula (1), Y is a substituent containing the aforementioned chain, and may be, for example, a substituent containing an aromatic structure having 6 to 18 carbon atoms or 6 to 12 carbon atoms. The chain may be, for example, a straight chain alkyl group containing at least 8, at least 9, at least 10, at least 11 or at least 12 carbon atoms. The alkyl group may contain up to 30, up to 25, up to 20 or up to 16 carbon atoms. Such a chain may be directly connected to the aromatic structure or via the above-mentioned linker.

The first block may be represented by the following formula (2) in another example.

(2)

R is hydrogen or an alkyl group having 1 to 4 carbon atoms, X is -C (= O) -O-, P is an arylene group having 6 to 12 carbon atoms, Q is an oxygen atom, Z is a chain Lt; / RTI > chain of 8 or more atoms.

In the above formula (2), P may be phenylene in another example, and Z may be a straight chain alkyl group having 9 to 20 carbon atoms, 9 to 18 carbon atoms, or 9 to 16 carbon atoms in another example. In the above, when P is phenylene, Q may be connected to the para position of the phenylene. In the above, the alkyl group, arylene group, phenylene group and chain may be optionally substituted with one or more substituents.

The second block of the fine phase-separated block polymer may be a block represented by the following formula (3) in one example.

(3)

In Formula 3 X ₂ is a single bond, an oxygen atom, sulfur _{atom, -S (= O) 2 -} , alkylene group, alkenylene group, alkynylene _{group, -C (= O) -X 1} - or -X ₁ -C (= O) - is, in the X ₁ is a single bond, oxygen atom, sulfur atom, -S (= O) ₂ -, and the alkylene, alkenylene or alkynylene group, W is at least one An aryl group containing a halogen atom.

In the above formula (3), X ₂ may be a single bond or an alkylene group in another example.

The aryl group of W in Formula 3 may be an aryl group having 6 to 12 carbon atoms or may be a phenyl group. The aryl group or phenyl group may have one or more, two or more, three or more, four or more, . ≪ / RTI > The number of halogen atoms in the above may be, for example, 30 or less, 25 or less, 20 or less, 15 or less, or 10 or less. As the halogen atom, a fluorine atom may be exemplified.

The block of Formula 3 may be represented by the following Formula 4 in another example.

[Chemical Formula 4]

In Formula 4 X ₂ are the same as defined in formula (2), the number of R ₁ to R ₅ is a halogen atom, each independently, comprise a hydrogen, an alkyl group, a haloalkyl group or a halogen atom, R ₁ to R ₅ is 1 Or more.

In Formula 4, R ₁ to R ₅ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a haloalkyl group having 1 to 4 carbon atoms, or halogen, wherein the halogen may be chlorine or fluorine.

In Formula 4, at least 2, at least 3, at least 4, at least 5 or at least 6 of R ₁ to R ₅ may include a halogen. The upper limit of the number of halogen atoms is not particularly limited and may be, for example, 12 or less, 8 or less, or 7 or less.

The block copolymer may be a block copolymer containing either one or both of the above two types of blocks together with another third block or containing only the two types of blocks. And may further include a third block which is fine-phase-separated with the above two types of blocks. Specific examples of the third block include, but are not limited to, poly (meth) acrylates, polyalkylene oxides, polyolefins, and polythiophenes. The sum of the first block and the second block may be 70 to 100 wt% based on the total weight of the block polymer, and the third block may be less than 30 wt% to the total weight of the block polymer.

At this time, the d-spacing value measured for the fine phase-separated block polymer may be 0.1 to 10 nm. The d-spacing can be measured by GIWAXS (Grazing-Incidence Wide-Angle X-ray Scattering). If the d-spacing is less than or greater than the above range, the ion conductivity may be lowered.

The oxidizing agent used in the production of the polymer solid electrolyte composition of the present invention may form an ion conductive polymer together with the ion supplying compound.

The oxidizing agent is an organic compound having a strong electron withdrawing group, and is not particularly limited as long as it is a compound capable of receiving electrons from a block polymer or from an ion supplying compound. However, the oxidizing agent is not limited to a persulfate group-containing compound, Group-containing compound. Specifically, the oxidizing agent is at least one selected from the group consisting of iron (III) p-toluene sulfonate, ammonium sulfate, ammonium persulfate, ammonium oxalate, ammonium perchlorate, 2,3-dichloro-5,6-dicyano- (III) p-toluene sulfonate, 2,3-dichloro-5,6-dihydroxybenzene, and the like can be used in view of the improvement of the ionic conductivity and the improvement of the cell performance. -Dicyano-1,4-benzoquinone, tetracyanoethylene, chloranil and mixtures thereof may be preferred.

As the solvent used for preparing the polymer solid electrolyte composition of the present invention, a solvent capable of dissolving the ion supplying compound may be used. As the organic solvent, for example, methanol, ethanol, 2-propanol, butanol, 2- ethoxyethanol N, N-dimethylformamide, N, N-dimethylformamide, N, N-dimethylformamide, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-dimethylacetamide, dimethylsulfoxide, hexamethylphosphamide, 1,3-dimethyl-2-imidazolidinone, triethylphosphate, and gamma-butyrolactone At least one selected from the group consisting of

The content of the solvent is limited in consideration of the viscosity of the finally obtained polymer solid electrolyte composition. That is, the higher the content of the solvent, the higher the viscosity of the final composition. Thus, the production process of the polymer solid electrolyte membrane is not easy. On the other hand, the lower the viscosity, the lower the workability.

The solution viscosity of the polymer solid electrolyte composition of the present invention at 30 캜 is not particularly limited, but is preferably 200 to 1,000 cP, preferably 300 to 800 cP or less, more preferably 500 to 700 cP . This viscosity control makes it possible to obtain a viscosity enhancing film fairness in the production of a polymer solid electrolyte composition as a film.

If the viscosity exceeds the above range, the thickness of the transverse direction (TD) due to the lowering of the flatness of the coating liquid becomes uneven and the flowability is lost and uniform coating becomes difficult. On the other hand, It is possible to prevent the occurrence of stain due to excessive flow of the coating liquid and to cause a problem that the MD (Mechanical Direction) thickness becomes uneven.

The polymer solid electrolyte composition as described above is excellent in all of the electronic conductivity, and may have an ionic conductivity of 10 ^-8 S / cm or more.

Polymer solid electrolyte membrane

The polymer solid electrolyte composition is subjected to a known film production process to form a polymer solid electrolyte membrane.

Examples of the film forming method include any suitable film forming method such as solution casting (solution casting), melt extrusion, calendering, or compression molding. Among these film forming methods, a solution casting method (solution casting method) or a melt extrusion method is preferable.

For example, a solution casting method (solution casting method) may be used for film production.

Solution casting is performed by coating a polymeric solid electrolyte composition. At this time, the polymer solid electrolyte composition may be directly coated on one of the anode and the cathode, or may be coated on a separate substrate, and then separated therefrom, followed by lapping with the anode and the cathode.

The substrate may be a glass substrate or a plastic substrate. Examples of the plastic substrate include polyethylene terephthalate, polyethylene naphthalate, polypropylene, polyethylene, cellulose triacetate, cellulose diacetate, alkyl (meth) acrylates, poly (meth) acrylate copolymers, polyvinyl alcohol Various plastic films such as polycarbonate, polystyrene, cellophane, polyvinylidene chloride copolymer, polyamide, polyimide, vinyl chloride-vinyl acetate copolymer, polytetrafluoroethylene, and polytrifluoroethylene have. A composite material composed of two or more of these materials may also be used, and a polyethylene terephthalate film having excellent light transmittance is particularly preferable. The thickness of the support is preferably 5 to 150 mu m, more preferably 10 to 50 mu m.

The coating can be applied, for example, by spin coating, dip coating, solvent casting, slot die coating, spray coating, Roll coating, extrusion coating, curtain coating, die coating, wire bar coating or knife coating may be used.

At this time, parameter adjustment in each process is required for producing a uniform film.

For example, the spin coating may be performed at 500 to 4000 rpm, the coating step may be divided into two steps, and in the case of doctor blade coating, a device having a thickness gap of 10 to 200 탆 may be used. In addition, when spray coating is carried out, spraying can be carried out with a spraying pressure of 0.5 to 20 MPa and a spraying number of 5 to 100 times. The design of such a process and the selection of parameters can be controlled by a person skilled in the art.

After the coating, an additional film drying step may be performed.

In this case, drying is preferably performed at 60 to 100 ° C for 30 seconds to 15 minutes although it depends on the content of each constituent component, the type of organic solvent, and the content ratio.

The drying may be performed by one of hot air drying, electromagnetic wave drying, vacuum drying, spray drying, drum drying and freeze drying, preferably by hot air drying.

After the coating and drying, the thickness of the polymer solid electrolyte membrane is finally formed to the thickness of the membrane to be manufactured, and if necessary, the coating-drying or coating step is performed at least once.

As another example, a melt extrusion method may be used for producing a film.

Examples of the melt extrusion method include a T-die method and an inflation method. The molding temperature is preferably 150 to 350 占 폚, more preferably 200 to 300 占 폚.

When a film is formed by the T-die method, a T-die is attached to the tip of a known single-screw extruder or a twin-screw extruder, and a rolled film is obtained by winding a film extruded in a film form.

If necessary, the heating and melting can be sequentially carried out through a first heat melting, a filtration filter passing, and a second heating and melting process. The temperature at which melt-extrusion is heated and melted may be from 170 캜 to 320 캜, preferably from 200 캜 to 300 캜. After being melt-extruded from the T die, it may be cooled and solidified using at least one or more metal drums held at 70 占 폚 to 140 占 폚. When a drum (casting roll) is used as described above, it may be extruded at the above-mentioned temperature condition or below.

A specific method for producing the polymer solid electrolyte membrane can be suitably selected by those skilled in the art.

Lithium secondary battery

The polymer solid electrolyte composition described above can be applied to a lithium secondary battery due to physical properties such as high lithium ion conductivity.

In particular, the polymer solid electrolyte composition of the present invention has a shape in which a block polymer is dispersed in a cured ion supplying compound, and not only the ion conductivity is improved, but also the electrical conductivity is improved due to the structural characteristics of the block polymer.

In addition, the voltage stability of the lithium secondary battery can be further improved by solving the problems (heat generation, explosion, film deterioration, etc.) that occur during operation of the lithium secondary battery due to heat resistance, durability, chemical resistance and flame retardancy.

The polymer solid electrolyte proposed in the present invention is applicable to a lithium secondary battery, and can be preferably used as a polymer solid electrolyte.

1 is a cross-sectional view showing a lithium secondary battery 10 according to the present invention. 1, a lithium secondary battery 10 includes a positive electrode 11, a negative electrode 15, and an electrolyte interposed therebetween. In this case, the polymer solid electrolyte 13 is used as the electrolyte, One polymer solid electrolyte is used.

The polymer solid electrolyte 13 described above exhibits high lithium ion conductivity while satisfying electrochemically stable potential difference, low electric conductivity and high temperature stability, and is preferably used as an electrolyte of a battery to improve the performance and thermal stability of the battery. Improve

In addition, the electrolyte 13 may further include a material used for this purpose in order to further increase the lithium ion conductivity.

If necessary, the polymer solid electrolyte 13 further comprises an inorganic solid electrolyte or an organic solid electrolyte. The inorganic solid electrolyte is a ceramic-based material, a crystalline or amorphous and crystalline materials can be _{used, Thio-LISICON (Li 3.} 25 Ge 0 .25 P 0. 75 S 4), Li 2 S-SiS 2, LiI -Li ₂ S-SiS ₂ , LiI-Li ₂ SP ₂ S ₅ , LiI-Li ₂ SP ₂ O ₅ , LiI-Li ₃ PO ₄ -P ₂ S ₅ , Li ₂ SP ₂ S ₅ , Li ₃ PS ₄ , _{Li 7 P 3 S 11, Li} 2 OB 2 O 3, Li 2 OB 2 O 3 -P 2 O 5, Li 2 OV 2 O 5 -SiO 2, Li 2 OB 2 O 3, Li 3 PO 4, Li 2 _{O-Li 2 WO 4 -B 2} O 3, LiPON, LiBON, Li 2 O-SiO 2, LiI, Li 3 N, Li 5 La 3 Ta 2 O12, Li 7 La 3 Zr 2 O 12, Li 6 BaLa 2 Ta ₂ O ₁₂ , Li ₃ PO _{(4-3 / 2w)} Nw (w is w <1), Li _{3 .} An inorganic solid electrolyte such as ₆ Si _{0 .6} P _{0 .4} O ₄ is possible.

Examples of the organic solid electrolyte include polymer materials such as polyethylene derivatives, polyethylene oxide derivatives, polypropylene oxide derivatives, phosphate ester polymers, agitation lysine, polyester sulfide, polyvinyl alcohol and polyvinylidene fluoride. A lithium salt may be mixed. At this time, they may be used alone or in combination of at least one.

The specific application method to the polymer solid electrolyte 13 is not particularly limited in the present invention, and a known method can be selected or selected by a person having ordinary skill in the art.

The lithium secondary battery 10 to which the polymer solid electrolyte 13 is applicable as an electrolyte is not limited to the anode 11 or the cathode 15 and can be applied to a battery such as a lithium-air battery, a lithium oxide battery, , A lithium metal battery, and an all solid battery.

The positive electrode 11 of the lithium secondary battery 10 is a layered compound such as lithium cobalt oxide (LiCoO ₂ ), lithium nickel oxide (LiNiO ₂ ), or a compound substituted with one or more transition metals; Lithium manganese oxides such as Li _{1 + x} Mn _{2 - x} O ₄ (0 _{? X?} 0.33), LiMnO ₃ , LiMn ₂ O ₃ and LiMnO ₂ ; Lithium copper oxide (Li ₂ CuO ₂ ); Vanadium oxides such as LiV ₃ O ₈ , LiFe ₃ O ₄ , V ₂ O ₅ and Cu ₂ V ₂ O ₇ ; Formula _{LiNi 1 - x M x O 2} ; Ni site type lithium nickel oxide which is represented by (M = Co, Mn, Al , Cu, Fe, Mg, B or Ga 0.01≤x≤0.3); Formula _{LiMn 2 - x M x O 2} (M = Co, Ni, Fe, Cr, Zn or Ta; 0.01≤x≤0.1), or _{Li 2 Mn 3 MO 8 (M} = Fe, Co, Ni, Cu or Zn Im A lithium manganese composite oxide represented by the following formula A lithium manganese composite oxide having a spinel structure represented by LiNi _x Mn _{2 - x} O ₄ ; LiMn ₂ O _{4 in} which a part of Li in the formula is substituted with an alkaline earth metal ion; Disulfide compounds; Iron, cobalt, nickel, copper, zinc and the like, such as Fe ₂ (MoO ₄ ) ₃ , Cu ₂ Mo ₆ S ₈ , FeS, CoS and MiS, scandium, ruthenium, titanium, vanadium, molybdenum, Oxides, sulfides or halides of TiS ₂ , ZrS ₂ , RuO ₂ , Co ₃ O ₄ , Mo ₆ S ₈ and V ₂ O ₅ may be used. However, no.

Such a cathode active material may be formed on the cathode current collector. The positive electrode current collector is not particularly limited as long as it has high conductivity without causing chemical changes in the battery. Examples of the positive electrode current collector include stainless steel, aluminum, nickel, titanium, sintered carbon, Nickel, titanium, silver, or the like may be used. At this time, the cathode current collector may use various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric having fine irregularities formed on the surface so as to increase the adhesive force with the cathode active material.

The negative electrode 15 is formed with a negative electrode mixture layer having a negative electrode active material on the negative electrode collector or a negative electrode mixture layer (for example, lithium foil) alone.

At this time, the kind of the negative electrode collector or the negative electrode material mixture layer is not particularly limited in the present invention, and a known material can be used.

The negative electrode current collector is not particularly limited as long as it has electrical conductivity without causing chemical change in the battery. For example, carbon, stainless steel, aluminum, nickel, titanium, sintered carbon, , Nickel, titanium, silver or the like, an aluminum-cadmium alloy, or the like can be used. The negative electrode current collector may be formed in various forms such as a film, a sheet, a foil, a net, a porous body, a foam, and a nonwoven fabric having fine irregularities formed on the surface thereof

In addition, the negative electrode active material may be one selected from the group consisting of crystalline artificial graphite, crystalline natural graphite, amorphous hard carbon, low crystalline soft carbon, carbon black, acetylene black, Ketjenblack, Super-P, graphene, or more carbon-based material, Si-based _{materials, LixFe 2 O 3 (0≤x≤1)} , Li x WO 2 (0≤x≤1), Sn x Me 1 - x Me 'y O z (Me: Mn, Fe , Pb, Ge; Me ': Al, B, P, Si, Group 1, Group 2, Group 3 elements of the periodic table, Halogen; 0? X? 1; 1? Y? Metal complex oxides; Lithium metal; Lithium alloy; Silicon-based alloys; Tin alloy; _{SnO, SnO 2, PbO, PbO} 2, Pb 2 O 3, Pb 3 O 4, Sb 2 O 3, Sb 2 O 4, Sb 2 O 5, GeO, GeO 2, Bi 2 O 3, Bi 2 O 4, Bi ₂ O ₅ and the like; Conductive polymers such as polyacetylene; Li-Co-Ni-based materials; Titanium oxide; Lithium titanium oxide, and the like, but the present invention is not limited thereto.

In addition to this, the negative electrode active material is SnxMe _{1 - x} Me _'y O _z (Me: Mn, Fe, Pb, Ge; Me': Al, B, P, Si, of the periodic table Group 1, Group 2, Group 3 element, Halogen; 0 <x? 1; 1? Y? 3; 1? Z? 8); _{SnO, SnO 2, PbO, PbO} 2, Pb 2 O 3, Pb 3 O 4, Sb 2 O 3, Sb 2 O 4, Sb 2 O 5, GeO, GeO2 2, Bi 2 O 3, Bi 2 O 4 , and Bi ₂ O ₅ and the like, and carbonaceous anode active materials such as crystalline carbon, amorphous carbon or carbon composite may be used alone or in combination of two or more.

At this time, the electrode mixture layer may further include a binder resin, a conductive material, a filler, and other additives.

The binder resin is used for bonding between the electrode active material and the conductive material and bonding to the current collector. Examples of such a binder resin include polyvinylidene fluoride (PVDF), polyvinyl alcohol, carboxymethylcellulose (CMC), starch, hydroxypropylcellulose, regenerated cellulose, polyvinylpyrrolidone, tetra Examples thereof include fluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene polymer (EPDM), sulfonated-EPDM, styrene-butadiene rubber, fluorine rubber and various copolymers thereof.

The conductive material is used to further improve the conductivity of the electrode active material. Such a conductive material is not particularly limited as long as it has electrical conductivity without causing chemical changes in the battery, for example, graphite such as natural graphite or artificial graphite; Carbon black such as carbon black, acetylene black, ketjen black, channel black, furnace black, lamp black, and summer black; Conductive fibers such as carbon fiber and metal fiber; Metal powders such as carbon fluoride, aluminum, and nickel powder; Conductive whiskers such as zinc oxide and potassium titanate; Conductive metal oxides such as titanium oxide; Polyphenylene derivatives and the like can be used.

The filler is optionally used as a component for suppressing the expansion of the electrode, and is not particularly limited as long as it is a fibrous material without causing a chemical change in the battery. Examples of the filler include olefin polymers such as polyethylene and polypropylene; Fibrous materials such as glass fibers and carbon fibers are used.

The shape of the lithium secondary battery 10 described above is not particularly limited and may be, for example, a jelly-roll type, a stack type, a stack-fold type (including a stack-Z-fold type), or a lamination- Preferably stack-folded.

An electrode assembly in which the negative electrode 15, the polymer solid electrolyte 13 and the positive electrode 11 are sequentially laminated is manufactured, and the electrode assembly is inserted into a battery case. Then, the battery assembly is sealed and assembled with a cap plate and a gasket, .

The lithium secondary battery 10 can be classified into various types of batteries such as a lithium-sulfur battery, a lithium-air battery, a lithium-oxide battery, and a lithium total solid battery depending on the anode / , Coin type, pouch type, etc., and can be divided into a bulk type and a thin film type depending on the size. The structure and the manufacturing method of these cells are well known in the art, and detailed description thereof will be omitted.

The lithium secondary battery 10 according to the present invention can be used as a power source for a device requiring a high capacity and a high rate characteristic. Specific examples of the device include a power tool which is powered by an electric motor and moves; An electric vehicle including an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), and the like; An electric motorcycle including an electric bike (E-bike) and an electric scooter (Escooter); An electric golf cart; And a power storage system, but the present invention is not limited thereto.

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 present invention. Such variations and modifications are intended to be within the scope of the appended claims.

Example 1

Poly (4-dodecyloctylphenyl methacrylate) -b-poly (pentafluorostyrene) (Mn 1.6 million, poly (4-dodecyloctylphenyl methacrylate) as the first block of the fine phase-separated block polymer and poly (pentafluorostyrene) Mw / Mn 1.15, 1 block vs. 2 block 62:38 parts by weight) was dissolved in 10 ml of a tetrahydrofuran solvent to prepare a solution.

To the solution was added 1 g of chlororanil as an oxidizing agent and 1 g of LiTFSI as an ion supplying compound and dissolved to prepare a polymer solid electrolyte composition.

Then, the polymer solid electrolyte composition was coated on a stainless steel electrode using a bar coater, dried at room temperature for one day, and further heated in an oven at 180 ° C for one day to prepare a 130 탆 thick polymer electrolyte membrane.

Example 2

(4-dodecyloctylphenyl methacrylate), poly (pentafluorostyrene), and poly (4-dodecyloctylphenyl methacrylate), which contain polyethylene oxide as the third block, as the first block of the micro- 2 g of pentafluorostyrene-b-polyethylene oxide (Mn 2.2 million, Mw / Mn 1.30, 1 block +2 block 3 block 76:24 parts by weight) was dissolved in 10 ml of tetrahydrofuran solvent to prepare a solution.

To the solution was added 1 g of chlororanil as an oxidizing agent and 1 g of LiTFSI as an ion supplying compound and dissolved to prepare a polymer solid electrolyte composition.

Then, the polymer solid electrolyte composition was coated on a stainless steel electrode using a bar coater, dried at room temperature for one day, and further heated in an oven at 180 ° C for one day to prepare a 130 탆 thick polymer electrolyte membrane.

Comparative Example 1: Preparation of polymer solid electrolyte composition

Except that the poly (methyl methacrylate) was used instead of the block polymer having a phase-separated structure in the same manner as in Example 1 to prepare a polymer solid electrolyte composition and a polymer membrane.

Experimental Example 1: Measurement of lithium ion conductivity

Maker: Lithium ion conductivity of the polymer solid electrolyte membranes prepared in the above Examples and Comparative Examples was measured using an impedance meter of VSP model of Bio-Logic SAS, and the results are shown in Table 1 below.

Experimental Example 2: Measurement of d-spacing

The d-spacing value was measured by GIWAXS (Grazing-Incidence Wide-Angle X-ray Scattering) and the results are shown in Table 1. [

Example 1 Example 2 Comparative Example 1 Ion conductivity 3 x 10 ^-6 S / cm 5 x 10 ^-5 S / cm Not measurable d-spacing 0.48 nm 0.42 nm Not measurable

As a result, as shown in Table 1, in Examples 1 and 2, the lithium ion conductivity was excellent and the d-spacing value was in the range of 0.1 to 10 nm, whereas in Comparative Example 1, the lithium ion conductivity was measured And no peaks were found to measure d-spacing.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention.

10: Lithium secondary battery
11: anode
13: Polymer solid electrolyte
15: cathode

Claims (4)

Ion-supplying compounds;
A block polymer having a phase-separated structure; And
A polymer solid electrolyte composition comprising an oxidizing agent. A polymer membrane comprising a polymer solid electrolyte composition comprising the block polymer having the phase-separated structure of claim 1. The polymer membrane according to claim 2, wherein the d-spacing value measured by GI-WAXS is 0.1 nm to 10 nm. The polymer membrane according to claim 2, wherein the ionic conductivity at 25 캜 is 10 ^-8 S / cm or more.

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