KR20160037616A - Lithium ion transfer material and method for manufacturing the same - Google Patents

Abstract

Provided in the present invention are a lithium ion transfer material, and a method for manufacturing the same. The lithium ion transfer material comprises a copolymer including a repeated unit of chemical formula A and a repeated unit of chemical formula B. The lithium ion transfer material has high lithium ion conductivity, and excellent heat resistance and durability.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a lithium ion transfer material,

TECHNICAL FIELD The present disclosure relates to a lithium ion transfer material and a method for manufacturing 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. The electrochemical device has received the most attention in this respect. Of these, the development of a rechargeable secondary battery has become a focus of attention. Recently, in developing such a battery, Research and development on the design of electrodes and batteries are underway.

Among the currently applied secondary batteries, the lithium secondary battery developed in the early 1990s has advantages such as higher operating voltage and much higher energy density than conventional batteries such as Ni-MH, Ni-Cd, and sulfuric acid-lead batteries using an aqueous electrolyte .

Generally, a lithium secondary battery includes a positive electrode, a negative electrode, and an electrode assembly including a separator interposed between the positive electrode and the negative electrode, and the nonaqueous electrolyte is injected into the battery case.

In the case of the lithium-sulfur battery, lithium polysulfide generated in the anode during charge reversal is dissolved in the electrolyte solution and oxidized at the cathode, and the capacity is slowed down. In addition, there is a problem in that the capacity of the battery due to the growth of dendrite There is a problem in stability because short circuit can be generated.

Accordingly, researches on materials for protecting the positive electrode, the negative electrode, and the separator to solve the above problems have been continued.

Korean Laid-Open Publication No. 2006-0116043

The present specification is intended to provide a lithium ion transfer material and a method of manufacturing the same.

An embodiment of the present application provides a lithium ion transfer material comprising a copolymer comprising a repeating unit represented by the following formula (A) and a repeating unit represented by the following formula (B).

 (A)

[Chemical Formula B]

In the above Formulas A and B,

X ₁ , X _2, and X ₃ , At least one of them is represented by the following general formula (11) and the others are the same or different and each independently represents one of the following Chemical Formulas (1) to (3)

Y ₁ is represented by any one of the following formulas (4) to (6)

m and n mean the number of repeating units, 2? m? 500, 2? n? 500,

(11)

[Chemical Formula 1]

(2)

(3)

In the above formula (11) and (1) to (3)

L ₁ is a direct bond or any _one of -CZ ₂ Z ₃ -, -CO-, -O-, -S-, -SO ₂ - and -SiZ ₂ Z ₃ -

Z ₂ and Z ₃ are the same or different and are each independently any one of hydrogen, an alkyl group, a trifluoromethyl group (-CF ₃ ) and a phenyl group,

S ₁ to S ₈ are the same as or different from each other, and each independently hydrogen; heavy hydrogen; A halogen group; Cyano; A nitrile group; A nitro group; A hydroxy group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted alkenyl group; A substituted or unsubstituted silyl group; A substituted or unsubstituted boron group; A substituted or unsubstituted amine group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,

a, b, c, p, q, s and t are the same or different and independently an integer of 0 or more and 4 or less,

r is an integer of 0 or more and 8 or less,

a 'is an integer of 1 or more and 5 or less,

[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

In the above formulas 4 to 6,

L ₂ is a direct bond or any one selected from -CO-, -SO ₂ -, and a substituted or unsubstituted divalent fluorene group,

d, e, f, g and h are the same as or different from each other, each independently an integer of 1 to 4,

b 'is an integer of 1 or more and 5 or less,

At least one of T ₁ to T ₅ is -SO ₃ Li and the others are the same or different and each independently hydrogen; heavy hydrogen; A halogen group; Cyano; A nitrile group; A nitro group; A hydroxy group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted alkenyl group; A substituted or unsubstituted silyl group; A substituted or unsubstituted boron group; A substituted or unsubstituted amine group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group.

Another embodiment of the present application provides a lithium secondary battery comprising the lithium ion transfer material.

Another embodiment of the present application provides a lithium-sulfur battery comprising the lithium ion transfer material.

Another embodiment of the present application provides a method of making the lithium ion transfer material.

The lithium ion transfer material according to one embodiment of the present application has a high lithium ion conductivity and excellent heat resistance and durability by including a copolymer including -SO3Li group and a rigid aromatic skeleton. Furthermore, when the lithium ion transfer material is used for a lithium secondary battery, specifically, a lithium-sulfur battery, it is possible to suppress the dendritic growth of the lithium polysulfide to increase the lifetime characteristics of the battery and to obtain a stable charge- .

1 is a graph illustrating the performance of a lithium-sulfur battery manufactured according to an embodiment of the present invention.
2 is an NMR graph showing the result of confirming the synthesis of the copolymer included in the lithium ion transfer material produced according to the production example of the present application.

Hereinafter, the present invention will be described in more detail.

One embodiment of the present application provides a lithium ion transfer material comprising a copolymer comprising the repeating unit of formula (A) and the repeating unit of formula (B).

The repeating unit of formula (A) is a hydrophobic repeating unit, and the repeating unit of formula (B) is a hydrophilic repeating unit. The "hydrophilic repeating unit" is a repeating unit containing a hydrophilic ion-transfer functional group -SO ₃ Li.

The lithium ion transfer material according to one embodiment of the present application contains a copolymer having a lithium salt structure containing a hydrophilic ion-transfer functional group -SO ₃ Li, and thus has an excellent lithium ion transfer capability. The content of hydrophilic ion-transfer functional groups -SO ₃ Li in the copolymer can be controlled to exhibit excellent lithium ion conductivity.

In addition, the lithium ion transfer material according to one embodiment of the present application contains a bulky fluorene group represented by the above formula (11) in the copolymer, so that heat resistance and strong physical properties due to a rigid aromatic skeleton The durability can be improved, and the enthalpy of entanglement of the polymer chain can increase the hydrodynamic volume, thereby facilitating the transmission of lithium ions.

The lithium ion transfer material according to one embodiment of the present application not only includes the functional group of -SO ₃ Li but also contains a bulky fluorine group, which not only improves the durability but also the lithium ion conductivity Is more excellent.

In particular, when used in a lithium secondary battery, specifically, a lithium-sulfur battery, the lithium polysulfide generated in the anode during charging and discharging is prevented from diffusing into the cathode, thereby preventing shorting of the battery due to the growth of lithium dendrite , The life characteristic of the battery is further increased, and a stable charge / discharge cycle can be obtained.

As used herein, the term "copolymer" may include structures such as alternating copolymers, block copolymers, random copolymers, and graft copolymers.

In one embodiment of the present application, the copolymer is a block copolymer. The block copolymer may also be a copolymer in which the blocks are randomly or alternatively combined.

As used herein, the term "block" may mean that the number of repeating units (units) in a polymer is two or more. In addition, the block may be contained in the polymer in one or more.

"는 인접한 치환기와 결합할 수 있는 위치를 나타낸다.In the present specification,

Quot; represents a position capable of bonding with an adjacent substituent.

Illustrative examples of such substituents are set forth below, but are not limited thereto.

In the present specification, examples of the halogen group include fluorine, chlorine, bromine or iodine.

In the present specification, the alkyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 1 to 60, particularly 1 to 40, more particularly 1 to 20. Specific examples include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, t-butyl, pentyl, hexyl and heptyl.

In the present specification, the alkenyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 2 to 60, more preferably 2 to 40, and more particularly 2 to 20.

In the present specification, the alkoxy group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 1 to 60, more preferably 1 to 40, and more particularly 1 to 20.

In the present specification, the cycloalkyl group is not particularly limited, but preferably has 3 to 60 carbon atoms, more preferably 3 to 40 carbon atoms, and more preferably 5 to 20 carbon atoms, and particularly preferably a cyclopentyl group and a cyclohexyl group.

In the present specification, the heterocycloalkyl group includes at least one of S, O and N, and is not particularly limited, but preferably has 2 to 60 carbon atoms, specifically 2 to 40, more specifically 3 to 20, A pentyl group, and a cyclohexyl group are preferable.

In the present specification, the number of carbon atoms of the amine group is not particularly limited, but is preferably 1 to 60, more preferably 1 to 40, and more particularly 1 to 20. Specific examples of the amine group include a methylamine group, a dimethylamine group, an ethylamine group, a diethylamine group, a phenylamine group, a naphthylamine group, a biphenylamine group, an anthracenylamine group, a 9- , A diphenylamine group, a phenylnaphthylamine group, a ditolylamine group, a phenyltolylamine group, a triphenylamine group, and the like, but are not limited thereto.

In the present specification, the aryl group may be monocyclic or polycyclic, and the number of carbon atoms is not particularly limited, but is preferably 6 to 60, particularly 6 to 40, more particularly 6 to 20. Specific examples of the aryl group include monocyclic aromatic and naphthyl groups such as phenyl group, biphenyl group, triphenyl group, terphenyl group and stilbene group, binaphthyl group, anthracenyl group, phenanthrenyl group, pyrenyl group, perylenyl group, But are not limited to, a cyclic aromatic group such as a cyclopentyl group, a cyclohexenyl group, a cyclohexenyl group, a cyclohexenyl group, a chlorenyl group, a fluorenyl group, an acenaphthacenyl group, a triphenylene group and a fluoranthene group.

In the present specification, the heteroaryl group includes at least one of S, O and N as a hetero atom, and the number of carbon atoms is not particularly limited, but is preferably 2 to 60, particularly 2 to 40, more particularly 3 to 20 . Specific examples of the heteroaryl group include pyridyl, pyrrolyl, pyrimidyl, pyridazinyl, furanyl, thienyl, imidazolyl, pyrazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, triazolyl, Thiazolyl, thiazolyl, pyrazinyl, thiopyranyl, diazinyl, oxazinyl, thiazinyl, dioxinyl, triazinyl, tetrazinyl, quinolyl, iso Quinazolinyl, quinazolinyl, isoquinazolinyl, acridinyl, phenanthridinyl, imidazopyridinyl, diazanaphthalenyl, triazainene, indolyl, benzothiazolyl, benzoxazolyl, benzimidazole There may be mentioned, but not limited to, a condensed ring of a benzyl group, a benzyl group, a benzyl group, a benzyl group, a benzyl group, a benzyl group, a benzyl group, a benzyl group,

,

,

,

등이 있다. In the present specification, the fluorenyl group may be substituted by another substituent, and substituents may be bonded to each other to form a ring. For example,

,

,

,

.

As used herein, the term "substituted or unsubstituted" A halogen group; A nitrile group; A nitro group; A hydroxy group; Cyano; C ₁ to C ₆₀ linear or branched alkyl; C ₂ to C ₆₀ straight or branched chain alkenyl; C ₂ to C ₆₀ linear or branched alkynyl; C ₃ to C ₆₀ monocyclic or polycyclic cycloalkyl; A C ₂ to C ₆₀ monocyclic or polycyclic heterocycloalkyl; C ₆ to C ₆₀ monocyclic or polycyclic aryl; Substituted or unsubstituted with at least one substituent selected from the group consisting of C ₂ to C ₆₀ monocyclic or polycyclic heteroaryl, substituted or unsubstituted with at least two substituents selected from the group consisting of the substituents exemplified above it means. As described above, when two or more substituents are connected to each other, the two or more substituents may be the same or different.

In one embodiment of the present application, m and n represent the number of repeating units, and 2? M? 200 and 2? N? 200.

In one embodiment of the present application, the ratio of m and n may be from 1: 9 to 7: 3. That is, when m + n is 1, n may have a ratio of 0.3 to 0.9.

In one embodiment of the present application, the ratio of m and n may be from 2: 8 to 6: 4. That is, when m + n is 1, n may have a ratio of 0.4 to 0.8.

In one embodiment of the present application, X ₁ and X ₂ May be represented by the formula (11).

In one embodiment of the present application, the formula (1) may be represented by the following formula (1-1).

[Formula 1-1]

In Formula 1-1, S ₁ , S ₂ , b, c and L ₁ are as defined in Formula 1.

In one embodiment of the present application, Formula 4 may be represented by Formula 4-1 below.

[Formula 4-1]

In Formula 4-1, T ₁ , T ₂ , d, e and L ₂ are as defined in Formula 4.

또는

이고, 나머지는 서로 동일하거나 상이하고, 각각 독립적으로 하기 구조식 중에서 선택된 어느 하나일 수 있다.According to one embodiment of the present application, in Formulas A and B, X ₁ , X _2, and X ₃ At least one of

or

And the others are the same as or different from each other, and each independently can be any one selected from the following structural formulas.

,

,

,

,

,

,

,

,

,

,

,

,

,

및

.

,

,

,

,

,

,

,

,

,

,

,

,

,

And

.

Wherein R and R 'are the same or different and are each independently -NO ₂ or -CF ₃ .

According to one embodiment of the present application, in formula (B), Y < ₁ > May be any one selected from the following structural formulas.

,

,

,

,

,

,

,

,

,

,

,

,

,

및

.

,

,

,

,

,

,

,

,

,

,

,

,

,

And

.

Wherein Q is -SO ₃ Li and Q 'is hydrogen or SO ₃ Li.

In one embodiment of the present application, M may be sodium, potassium or lithium.

In one embodiment of the present application, the copolymer may further comprise a repeating unit represented by the following formula (C).

≪ RTI ID = 0.0 &

According to one embodiment of the present application, in the above formula (C), Z is a trivalent organic group.

In one embodiment of the present application, the repeating unit of the above-mentioned formula (C) is a brancher and serves to link or crosslink the polymer chain. Depending on the number of repeating units of formula (C), branches may be formed on the chain, or the chains may be crosslinked with each other to form a net-like structure.

In one embodiment of the present application, in the above formula (C), Z is a trivalent organic group, and can be extended with an additional repeating unit in each of three directions to elongate the polymer chain.

In one embodiment of the present application, the mechanical properties can be enhanced by using a branche which is a repeating unit of the above-mentioned formula (C).

In one embodiment of the present application, when the number of repeating units of the repeating unit represented by the formula (C) is k, k may be 1 or more and 300 or less.

In one embodiment of the present application, the repeating unit of formula (C) may be a polymer repeating unit constituting the main chain. For example, Z may be connected to at least one selected from X ₁ , X ₂ , X ₃ and Y ₁ to form one repeating unit. One repeating unit formed as described above may form a main chain. In this case, the number of repeating units is equal to k.

In the present specification, Z, X ₁ , X ₂ , X ₃ and Y ₁ , Each of them has a linking group of oxygen (-O-). The oxygen linkage is a linking group in which the compound escapes by condensation polymerization and remains in the chain. For example, when the dihalide-based monomer and the diol-based monomer are polymerized, HF is released and only oxygen (-O-) remains in the chain.

According to one embodiment of the present application, in the above formula (C), Z is represented by the following formula (C-1) or (C-2).

[Chemical formula C-1]

[Chemical formula C-2]

In the above formulas C-1 and C-2,

Z ₁ may be represented by any one of the following formulas (7) to (9).

(7)

[Chemical Formula 8]

[Chemical Formula 9]

In the above formulas (7) to (9)

L ₃ To L ₆ are the same or or different and each is connected directly, independently of each other, -O-, -CO- or -SO ₂ -, and

E ₁ to E ₇ are the same or different from each other, and each independently hydrogen; heavy hydrogen; A halogen group; Cyano; A nitrile group; A nitro group; A hydroxy group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted alkenyl group; A substituted or unsubstituted silyl group; A substituted or unsubstituted boron group; A substituted or unsubstituted amine group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,

c ', d', e 'and h' are the same or different and each independently an integer of 0 to 4,

f ', g' and i 'are the same as or different from each other and each independently an integer of 0 or more and 3 or less,

X ₄ and X ₅ are the same as or different from each other, and each independently is the same as defined in X ₃ or Y _{1 in} the above formula (B).

According to one embodiment of the present application, in the above formula (C), Z may be any one selected from the following formulas.

,

,

,

,

,

,

,

,

및

.

,

,

,

,

,

,

,

,

And

.

In one embodiment of the present application, the repeating unit of formula (A) can be represented by the following structural formula.

In the above formula, m is the same as described above.

In one embodiment of the present application, the repeating unit of formula (B) can be represented by the following structural formula.

,

,

,

,

In the above structural formulas, n is the same as described above.

In one embodiment of the present application, the weight average molecular weight of the copolymer may be 500 or more and 5,000,000 or less, specifically 10,000 or more and 2,000,000 or less, more specifically 20,000 or more and 1,000,000 or less. When the weight average molecular weight of the copolymer is within the above range, the mechanical properties of the lithium ion transfer material including the copolymer are not deteriorated and the solubility of the appropriate copolymer can be maintained.

Another embodiment of the present application provides a lithium secondary battery comprising the lithium ion transfer material.

Generally, a lithium secondary battery includes a positive electrode, a negative electrode, and an electrode assembly including a separator interposed between the positive electrode and the negative electrode, and the nonaqueous electrolyte is injected into the battery case.

The lithium ion transfer material according to one embodiment of the present application can be used as a separation membrane of a lithium secondary battery.

Another embodiment of the present application provides a lithium-sulfur battery comprising the lithium ion transfer material.

The lithium-sulfur battery uses a sulfur-based compound having a sulfur-sulfur bond as a cathode active material and a carbon-based material in which an alkali metal such as lithium or a metal ion such as lithium ion is intercalated or deintercalated is used as a negative active material Battery. The reduction energy is stored and generated by the oxidation-reduction reaction in which the sulfur-sulfur bond is cut off during the reduction reaction and the oxidation number of sulfur is reduced and the sulfur-sulfur bond is formed again while the oxidation number of sulfur increases during charging .

In the lithium-sulfur battery, when sulfur is discharged to the electrolyte during the oxidation-reduction reaction, not only the life of the battery is deteriorated but also the lithium polysulfide, which is a reducing material of sulfur, is eluted when an appropriate electrolyte is not selected. There is a problem that it can not be performed. As described above, when the lithium ion-transfer material according to one embodiment of the present application is included in the lithium-sulfur battery, the lithium polysulfide is prevented from leaching out from participation in the electrochemical reaction to increase the lifetime characteristics of the battery And a stable charge-discharge cycle can be obtained.

Generally, a lithium-sulfur battery includes a positive electrode; cathode; And the separation membrane located between the anode and the cathode. Further, the lithium-sulfur battery may further include an electrolyte impregnated in the positive electrode, the negative electrode, and / or the separator, and the electrolyte may include a lithium salt and an organic solvent.

The lithium ion transfer material according to one embodiment of the present application can be used as a separation membrane of a lithium-sulfur battery.

Another embodiment of the present application provides a method of making the lithium ion transfer material.

Typically, the lithium ion transfer material can be produced by the following methods, but the following production methods are only examples for producing the lithium ion transfer material of the present application, and the production thereof is not limited by the following methods .

In one embodiment of the present application, a process for producing a lithium ion transfer material comprising a copolymer comprising a repeating unit of the formula (A) and a repeating unit of the formula (B)

Polymerizing an aromatic diol-based monomer and an aromatic dihalogen-based monomer to prepare a hydrophobic repeating unit; And

An aromatic repeating unit in the manufactured hydrophobic diol-based monomer or an aromatic dihalogen-based monomer, and -SO ₃ Li substituent of an aromatic diol monomer, or by the addition of aromatic dihalogen-based monomer having a substituent -SO ₃ Li and polymerizing a hydrophilic repeating unit having And at the same time preparing a copolymer.

In one embodiment of the present application, a process for producing a lithium ion transfer material comprising a copolymer comprising a repeating unit of the formula (A) and a repeating unit of the formula (B)

An aromatic diol monomer or an aromatic dihalide monomer, and an aromatic diol monomer having a bivalent heterocyclic group containing at least two nitrogen atoms, or an aromatic dihalogen monomer having a -SO ₃ Li substituent, are polymerized to obtain a hydrophilic repeating unit Producing; And

Adding an aromatic diol monomer and an aromatic dihalide monomer to the hydrophilic repeating unit thus prepared, and polymerizing to prepare a hydrophobic repeating unit and preparing a copolymer.

In one embodiment of the present application, a process for producing a lithium ion transfer material comprising a copolymer comprising a repeating unit of the formula (A) and a repeating unit of the formula (B)

Polymerizing an aromatic diol-based monomer and an aromatic dihalogen-based monomer to prepare a hydrophobic repeating unit;

Preparing a hydrophilic repeating unit by the polymerization of an aromatic diol-based monomer or an aromatic dihalogen-based monomer, and -SO ₃ Li aromatic diol monomer or -SO ₃ Li aromatic dihalogen-based monomer having a substituent having a substituent; And

And reacting the produced hydrophobic repeating unit and the hydrophilic repeating unit thus prepared to prepare a copolymer.

In one embodiment of the present application, a process for producing a lithium ion transfer material comprising a copolymer comprising a repeating unit of the formula (A) and a repeating unit of the formula (B)

Aromatic diol-based monomers; Aromatic dihalogen monomers; And by polymerizing an aromatic diol monomer or -SO ₃ Li aromatic dihalogen-based monomer having a substituent group having a substituent -SO ₃ Li at the same time for producing the hydrophobic repeat unit and hydrophobic repeating unit and a step for producing the copolymer.

In one embodiment of the present application, a process for producing a lithium ion transfer material comprising a copolymer comprising a repeating unit of the formula (A) and a repeating unit of the formula (B)

The copolymer is further polymerized by adding a branching agent in at least one of the steps of preparing the copolymer, and the copolymer further comprises the repeating unit of the above-mentioned formula (C).

In one embodiment of the present application, the branche may be one in which a halogen group or a hydroxy group is connected to the end of any structural formula selected from the following structural formulas.

,

,

,

,

,

,

,

,

, 및

.

,

,

,

,

,

,

,

,

, And

.

Hereinafter, the present application will be described in more detail by way of examples. However, the following embodiments are intended to illustrate the present application, and the scope of the present application is not limited thereby.

≪ Preparation Example > Preparation of lithium ion transfer material

 (Manufactured by BRANDER)

5 g (18.8 mmol) of 1,3,5-benzenetricarbonyltrichloride, 6.7 g (50.0 mmol) of aluminum chloride and 50 mL of distilled dichloromethane (DCM) were added to a 250 mL round- At 25 占 폚 for 30 minutes. Next, 20 mL of dichloromethane and 4.5 g (48.8 mmol) of fluorobenzene were added to a dropping funnel of 100 mL, and this fluorobenzene solution was added dropwise to the reaction product of the round flask. The reaction mixture was stirred for 4 hours under a nitrogen atmosphere, 20 mL of distilled water was added thereto, and the reaction mixture was further stirred for 12 hours or more. The reaction product was extracted with dichloromethane and the organic solvent was removed. The obtained crude product was recrystallized from ethanol to obtain a white branched copolymer [3,5-bis (4-fluorobenzoyl) phenyl] (4-fluorophenyl) methanone (yield: 70%). The structure of the above [3,5-bis (4-fluorobenzoyl) phenyl] (4-fluorophenyl) methanone was confirmed by 1H-NMR, 13C-NMR spectroscopy and elemental analysis. (Ppm) 8.24 (s, 3H), 7.96 (m, 6H), 7.46 (m, 6H)

(Manufacture of branched minor blocks)

After a dean-stark apparatus was connected to a 500 mL round flask, 17.238 g (79.00 mmol) of 4,4'-difluorobenzophenone, [3,5-bis (4-fluorobenzoyl) 24.512 g (69.92 mmol) of 9,9-bis (4-hydroxyphenyl) fluorene, 19.327 g (139.84 mmol) of potassium carbonate, 200 mL of methyl-2-pyrrolidone, and 120 mL of benzene were added. The reaction mixture was then stirred in an oil bath at 140 占 폚 under nitrogen for 4 hours to react the azotrope adsorbed on the molecular sieves of the Dean-Stark apparatus while the benzene was refluxed After the reaction mixture was completely removed with nitrogen, the reaction temperature was raised to 182 ° C, and 100 mL of N-methyl-2-pyrrolidone was further added thereto to carry out condensation polymerization for 12 hours. After the completion of the reaction, the temperature of the reaction product was reduced to 60 ° C, and about 200 mL of N-methyl-2-pyrrolidone in the reaction product was removed while a vacuum was applied and the temperature of the reaction product was raised to 120 ° C. Then, the temperature of the reaction mixture was reduced to room temperature, 300 mL of methyltetrahydrofuran (THF) was added to dilute the reaction product, the diluted reaction product was poured into 3 L of methanol to separate the copolymer from the solvent, (cake form) was dried in a vacuum oven at 80 캜 for 12 hours or more to prepare 34.8 g of a branched white minor block having a weight average molecular weight of 5,000 g / mol and a terminal group characterized by flourine elements.

(Production of polyarylene ether copolymer containing lithium sulfonate)

13.082 g (2.616 mmol) of the branched minor block prepared as described above, 10.162 g (46.572 mmol) of 4,4'-difluorobenzophenone, [3,5-bis (4-fluorobenzoyl) phenyl] (2.093 mmol) of lithium aluminum hydride, 11.945 g (52.328 mmol) of hydroquinone sulfonic acid lithium salt, 14.463 g (104.650 mmol) of potassium carbonate, 200 mL of dimethyl sulfoxide and 120 mL of benzene were added . The reaction mixture was then stirred in an oil bath at 140 占 폚 under nitrogen for 4 hours to react the azotrope adsorbed on the molecular sieves of the Dean-Stark apparatus while the benzene was refluxed After the reaction mixture was completely removed with nitrogen, the reaction temperature was elevated to 182 ° C, and 100 mL of dimethyl sulfoxide was further added thereto to conduct condensation polymerization for 12 hours. After completion of the reaction, 200 mL of dimethyl sulfoxide was added to dilute the reactant, and the diluted reaction product was poured into 3 L of methanol to separate the copolymer from the solvent. The resulting cake was filtered, A lithium ion transfer material comprising a polyarylene ether copolymer containing lithium sulfonate, which was dried in an oven for 12 hours or more, and in which branched and hydrophilic blocks were alternately chemically bonded, was prepared. The weight average molecular weight of the copolymer was about 800,000.

The results of confirmation of the synthesis of the copolymer prepared according to the above Preparation Example are shown in FIG. 2 is a ¹ H NMR measurement graph of the copolymer contained in the lithium ion transfer material prepared according to the above Preparation Example. 2, it can be confirmed that a polyarylene ether copolymer containing lithium sulfonate was synthesized. The structure of the lithium sulfonate-containing polyarylene ether copolymer is schematically shown in Fig. 2, and the values of the repeating units n and m are the same as described above.

<Examples>

The conductive carbon and sulfur having electric conductivity were mixed through a ball mill process with a conductive carbon: sulfur weight ratio (wt%) of 30:70 (21 g: 49 g) to obtain a sulfur-carbon composite. 70.0 g of the positive electrode active material containing the complex, 20.0 g of Super-P as a conductive material, 10.0 g of polyvinylidene fluoride as a binder, and 500 g of N-methyl-2-pyrrolidone as a solvent were added to the total weight of the positive electrode active material slurry To prepare a cathode active material slurry, and then coated on an aluminum current collector to prepare a cathode active material.

Polyethylene coated with a lithium ion transfer material containing the copolymer prepared in the above Preparation Example was used as a separator.

Of: (a volume ratio of 1: 1) with the positive electrode, was used as a lithium foil having a thickness of about 150 ㎛ as the cathode, a 1M concentration of the electrolyte LiN (CF ₃ SO _{2) 2} was dissolved in dimethoxyethane-dioxolane And a lithium-sulfur battery was prepared using the separator.

<Comparative Example>

A lithium-sulfur battery was prepared in the same manner as in Example 1, except that the lithium ion transfer material containing the copolymer of Example 1 was not coated in the separator.

<Experimental Example>

The capacity retention ratio with respect to the initial capacity and the point at which the battery operation was stopped due to the short circuit by 0.1 C / 0.1 C charge / discharge were measured, and the results are shown in FIG. The experimental conditions were discharge / charge (0.1 C / 0.1 C) C-rate and cut-off voltage of 1.5 ~ 2.8 V.

As a result of charging / discharging tests on the batteries prepared in the examples and the comparative examples, it was confirmed that the shuttle reaction delayed in the layer transition was suppressed in the examples. The dashed line in FIG. 1 is the first charge and the second discharge graph.

As shown in FIG. 1, it can be seen that the initial capacity of the example is about 150 mAh / g higher than that of the comparative example.

Further, when the second discharge capacity is checked, it is seen that the capacity is reduced by about 40% in the comparative example, but the capacity reduction is hardly caused in the embodiment.

Also, in the comparative example, it can be confirmed that charging continues without increasing the voltage in the vicinity of 2.35 V, which is known to be caused by shuttle reaction. Short-chain polysulfides that are insoluble in the electrolytic solution upon charging are converted into long-chain polysulfides that are soluble, wherein the long-chain polysulfide The concentration is increased, and it is diffused again to the lithium, which is the cathode, to be chemically converted into a short chain polysulfide. When the shuttle reaction occurs, the capacity is decreased due to the loss of the active material, and the lifetime characteristic is also deteriorated. In the case of the comparative example, it can be predicted that the shuttle reaction occurs when the voltage continues to rise without increasing the voltage in the vicinity of 2.35 V, but in the case of the embodiment, such shuttle reaction is not observed and the voltage is increased.

Accordingly, when the lithium ion transfer material according to one embodiment of the present application is coated according to the embodiment, the effect of suppressing the shuttle reaction can be exhibited, and the lifetime characteristics can be improved as compared with the non-coated comparative example.

As shown in FIG. 1, in the case of a battery using a lithium ion transfer material according to one embodiment of the present application as a separator, the effect of inhibiting the shuttle reaction upon charging and discharging can be confirmed.

Therefore, the lithium ion transfer material according to the present application can exhibit excellent effects.

Claims (15)

A lithium ion transfer material comprising a copolymer comprising a repeating unit of formula (A) and a repeating unit of formula (B):
(A)

[Chemical Formula B]

In the above Formulas A and B,
X ₁ , X _2, and X ₃ , At least one of them is represented by the following general formula (11) and the others are the same or different and each independently represents one of the following Chemical Formulas (1) to (3)
Y ₁ is represented by any one of the following formulas (4) to (6)
m and n mean the number of repeating units, 2? m? 500, 2? n? 500,
(11)

[Chemical Formula 1]

(2)

(3)

In the above formula (11) and (1) to (3)
L ₁ is a direct bond or any _one of -CZ ₂ Z ₃ -, -CO-, -O-, -S-, -SO ₂ - and -SiZ ₂ Z ₃ -
Z ₂ and Z ₃ are the same or different and are each independently any one of hydrogen, an alkyl group, a trifluoromethyl group (-CF ₃ ) and a phenyl group,
S ₁ to S ₈ are the same as or different from each other, and each independently hydrogen; heavy hydrogen; A halogen group; Cyano; A nitrile group; A nitro group; A hydroxy group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted alkenyl group; A substituted or unsubstituted silyl group; A substituted or unsubstituted boron group; A substituted or unsubstituted amine group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,
a, b, c, p, q, s and t are the same or different and independently an integer of 0 or more and 4 or less,
r is an integer of 0 or more and 8 or less,
a 'is an integer of 1 or more and 5 or less,
[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

In the above formulas 4 to 6,
L ₂ is a direct bond or any one selected from -CO-, -SO ₂ -, and a substituted or unsubstituted divalent fluorene group,
d, e, f, g and h are the same as or different from each other, each independently an integer of 1 to 4,
b 'is an integer of 1 or more and 5 or less,
At least one of T ₁ to T ₅ is -SO ₃ Li and the others are the same or different and each independently hydrogen; heavy hydrogen; A halogen group; Cyano; A nitrile group; A nitro group; A hydroxy group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted alkenyl group; A substituted or unsubstituted silyl group; A substituted or unsubstituted boron group; A substituted or unsubstituted amine group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group. The compound according to claim 1, wherein X ₁ , X ₂ and X ₃ At least one of

or

ego,
And the others are the same or different from each other, and each independently is selected from the following structural formulas: Li ion transfer material:

,

,

,

,

,

,

,

,

,

,

,

,

And

,
In the above formulas, R and R 'are the same or different and each independently -NO ₂ or -CF ₃ . The method according to claim 1,
Wherein Y &lt; _{1 &gt;} is any one selected from the following structural formulas:

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

,

And

,
In the above formula, Q is -SO ₃ Li and Q 'is hydrogen or SO ₃ Li. The method according to claim 1,
Wherein the copolymer further comprises a repeating unit of the following formula (C): &lt; EMI ID =
&Lt; RTI ID = 0.0 &

In the above formula (C), Z is a trivalent organic group. The method of claim 4,
And Z is a group represented by the following formula (C-1) or (C-2):
[Chemical formula C-1]

[Chemical formula C-2]

In the above formulas C-1 and C-2,
Z ₁ is represented by any one of the following formulas (8) to (10)
[Chemical Formula 8]

[Chemical Formula 9]

[Chemical formula 10]

In the general formulas (8) to (10)
L ₃ To L ₆ are the same or or different and each is connected directly, independently of each other, -O-, -CO- or -SO ₂ -, and
E ₁ to E ₇ are the same or different from each other, and each independently hydrogen; heavy hydrogen; A halogen group; Cyano; A nitrile group; A nitro group; A hydroxy group; A substituted or unsubstituted alkyl group; A substituted or unsubstituted cycloalkyl group; A substituted or unsubstituted alkoxy group; A substituted or unsubstituted alkenyl group; A substituted or unsubstituted silyl group; A substituted or unsubstituted boron group; A substituted or unsubstituted amine group; A substituted or unsubstituted aryl group; Or a substituted or unsubstituted heteroaryl group,
c ', d', e 'and h' are the same or different and each independently an integer of 0 to 4,
f ', g' and i 'are the same as or different from each other and each independently an integer of 0 or more and 3 or less,
X ₄ and X ₅ are the same as or different from each other, and each independently is the same as defined in X ₃ or Y _{1 in} the above formula (B). The method of claim 5,
Wherein Z &lt; _{1 &gt;} is any one selected from the following structural formulas:

,

,

,

,

,

,

,

,

And

. The method according to claim 1,
Wherein the copolymer has a weight average molecular weight of 500 to 5,000,000. A lithium secondary battery comprising the lithium ion transfer material according to any one of claims 1 to 7. A lithium-sulfur battery comprising the lithium ion-transferring material according to any one of claims 1 to 7. Polymerizing an aromatic diol-based monomer and an aromatic dihalogen-based monomer to prepare a hydrophobic repeating unit; And
An aromatic repeating unit in the manufactured hydrophobic diol-based monomer or an aromatic dihalogen-based monomer, and -SO ₃ Li substituent of an aromatic diol monomer, or by the addition of aromatic dihalogen-based monomer having a substituent -SO ₃ Li and polymerizing a hydrophilic repeating unit having And simultaneously preparing a copolymer;
Lt; RTI ID = 0.0 &gt; 1, &lt; / RTI &gt; Preparing a hydrophilic repeating unit by the polymerization of an aromatic diol-based monomer or an aromatic dihalogen-based monomer, and -SO ₃ Li aromatic diol monomer or -SO ₃ Li aromatic dihalogen-based monomer having a substituent having a substituent; And
Adding an aromatic diol monomer and an aromatic dihalogen monomer to the prepared hydrophilic repeating unit and polymerizing to prepare a hydrophobic repeating unit and preparing a copolymer;
Lt; RTI ID = 0.0 &gt; 1, &lt; / RTI &gt; Polymerizing an aromatic diol-based monomer and an aromatic dihalogen-based monomer to prepare a hydrophobic repeating unit;
Preparing a hydrophilic repeating unit by the polymerization of an aromatic diol-based monomer or an aromatic dihalogen-based monomer, and -SO ₃ Li aromatic diol monomer or -SO ₃ Li aromatic dihalogen-based monomer having a substituent having a substituent; And
Preparing a copolymer by reacting the produced hydrophobic repeating unit and the prepared hydrophilic repeating unit;
Lt; RTI ID = 0.0 &gt; 1, &lt; / RTI &gt; Aromatic diol-based monomers; Aromatic dihalogen monomers; And -SO ₃ claims that by polymerizing an aromatic dihalogen-based monomer having a Li aromatic diol monomer or -SO ₃ Li substituent having a substituent comprising the step of producing the copolymer at the same time for producing the hydrophobic repeat unit and hydrophobic repeating unit 1 &Lt; / RTI &gt; wherein the copolymer comprises a copolymer according to claim 1. The method according to any one of claims 10 to 13,
And a step of adding a brancer in at least one of the steps of preparing the copolymer,
Wherein the copolymer further comprises a repeating unit represented by the following formula (C): &lt; EMI ID =
&Lt; RTI ID = 0.0 &

In the above formula (C), Z is a trivalent organic group. 15. The method of claim 14,
Wherein the brancer comprises a copolymer wherein a halogen group or a hydroxyl group is connected to the end of any one of structural formulas selected from the following structural formulas:

,

,

,

,

,

,

,

,

, And

.

Images