KR101705267B1 - Solid electrolytes for all solid state rechargeable lithium battery, methods for manufacturing the same, and all solid state rechargeable lithium battery including the same - Google Patents

Abstract

The present invention relates to a solid electrolyte complex, a method for producing the same, and a whole solid battery including the same, wherein a plurality of sulfide-based solid electrolyte particles; And an organic liquid electrolyte distributed in the pores between the plurality of sulfide-based solid electrolyte particles, wherein the solid electrolyte complex is in powder form, and a method for producing the same, and a pre-solid battery including the same can do.

Description

TECHNICAL FIELD [0001] The present invention relates to a solid electrolyte composite, a method of manufacturing the same, and a solid electrolyte including the same. [0002] The present invention relates to a solid electrolyte composite,

A solid electrolyte complex, a method for producing the same, and a whole solid battery including the same.

Most lithium secondary batteries currently commercialized use an organic liquid electrolyte in which a lithium salt is dissolved in a flammable organic solvent. However, since the organic liquid electrolyte has a potential danger of leakage, ignition, explosion, etc., a solid electrolyte is attracting attention as an alternative for solving the problem.

Unlike an organic liquid electrolyte, a solid electrolyte can not only ensure safety but also has advantages in terms of high capacity and cost reduction of a battery. Specifically, a battery using a solid electrolyte, that is, a whole solid battery, can be divided into a thin film type and a thick film type. Among these, the thick-film type all-solid-state cell is a form in which a solid electrolyte is simply replaced by an organic liquid electrolyte, and is called a so-called composite-type all-solid-state cell.

Here, the solid electrolyte is applied in the form of an electrode layer in which the active material is combined with the active material (in some cases, the conductive material particles are further combined). The thickness of the electrode layer can be controlled close to the currently commercialized lithium ion battery.

However, in order to excellently exhibit the electrochemical performance of the all-solid-state cell to which such a solid electrolyte is applied, it is required that the solid electrolyte and the active material, which are the base of the electrode layer, have excellent contact properties between particles. However, in general, the solid electrolyte has characteristics that it is difficult to realize in the form of a completely dense pellet which hardly contains pores even when pressed, and is in intimate contact with the active material in the electrode layer There is a limit.

Further, in order for the solid-state cell to be driven stably, interfacial stability between the solid electrolyte and the active material is required. However, generally, the chemical properties of the solid electrolyte and the active material are different, and it is difficult for the interface at which they are in contact to be stably maintained.

Therefore, an electrolyte capable of solving the problems of each of the organic liquid electrolyte and the solid electrolyte has been demanded, but researches on it are still lacking.

In order to solve the above-mentioned problems, the present inventors have selected a sulfide-based solid electrolyte and an organic liquid electrolyte excellent in thermal stability with little reactivity thereof, and these are combined. The details of this are as follows.
In one embodiment of the present invention, a plurality of sulfide-based solid electrolyte particles; And an organic liquid electrolyte distributed in the pores between the plurality of sulfide-based solid electrolyte particles, wherein the solid electrolyte complex is in powder form.
In another embodiment of the present invention, a method of producing the solid electrolyte complex by a simple mixing process can be provided.
In another embodiment of the present invention, a plurality of electrode active material particles; A plurality of sulfide-based solid electrolyte particles; Wherein the plurality of electrode active material particles and the plurality of sulfide-based solid electrolyte particles are uniformly distributed and the organic liquid electrolyte is distributed in a gap between the respective particles, .
According to another embodiment of the present invention, there can be provided a solid electrolyte composite comprising the solid electrolyte complex or the composite electrode.

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In one embodiment of the present invention, a plurality of sulfide-based solid electrolyte particles; And an organic liquid electrolyte distributed in a gap between the plurality of sulfide-based solid electrolyte particles, wherein the solid electrolyte complex is in powder form.

The description of the plurality of sulfide-based solid electrolyte particles is as follows.

The plurality of sulfide-based solid electrolyte particles may be a plurality of lithium sulfide-based solid electrolyte particles, a plurality of sodium sulfide-based solid electrolyte particles, or a mixture thereof.

Here, the lithium sulfide-based solid electrolyte particles may be represented by the following general formula (1).

Li _a PM _b S _c X _d

In the above Formula 1, M, B, Al, Ga, In, Si, Ge, Sn, Pb, As, Sb, Bi, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, , Mo, Tc, Ru, Rh, Pd, Ag, Hf, Ta or W, X = F, Cl, Br, or I and 0? A? 6, 0? B? 6, 0? , 0? D? 6.

Independently, the sodium sulfide-based solid electrolyte particle may be represented by the following formula (2).

???????? Na _a PM _b S _c X _d ?????

In the above Formula 2, M, B, Al, Ga, In, Si, Ge, Sn, Pb, As, Sb, Bi, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, , Mo, Tc, Ru, Rh, Pd, Ag, Hf, Ta or W, X = F, Cl, Br, or I and 0? A? 6, 0? B? 6, 0? , 0? D? 6.

On the other hand, the plurality of sulfide-based solid electrolyte particles may be a plurality of crystalline sulfide-based solid electrolyte particles, a plurality of amorphous sulfide-based solid electrolyte particles, or a mixture thereof.

The description of the organic liquid electrolyte is as follows.

The organic liquid electrolyte may be a substance in which a metal salt is dissociated into an ion conductive organic solvent, an ion conductive liquid, or a mixture thereof.

Specifically, the molar ratio of the ion conductive organic solvent to the metal salt in the ion-conductive organic solvent in which the metal salt is dissociated (the number of moles of ion conductive organic solvent: the number of moles of metal salt) may be 1: 0.5 to 1: 5.

In this case, the metal salt in the ion-conductive organic solvent in which the metal salt is dissociated is at least one selected from the group consisting of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium hexafluoroacetate, lithium perchlorate, lithium tetrachloroaluminate, lithium bis oxalate borate, lithium (C _x F _{2x + 1} SO ₂ ) (C _y F _{2y + 1} SO ₂ ) (where x and y are natural numbers), sodium hexafluorophosphate, sodium tetrafluoro Borate, sodium hexafluoroantimonide, sodium perchlorate, sodium chloride, sodium iodide, each derivative thereof, or a mixture thereof.

Independently, the ion conductive organic solvent in the material in which the metal salt is dissociated into the ion conductive organic solvent is selected from cyclic carbonate solvent, glyme solvent, and ether solvent .

On the other hand, the ion conductive liquid may be at least one selected from the group consisting of ammonium, imidazolium, oxazolium, piperidinium, pyrazinium, pyrazolium, (Pyridazinium), Pyridinium, Pyrimidinium, Pyrrolidinium, Pyrrolinium, Pyrrolium, Triazolium, and combinations thereof. And at least one cation selected from the group consisting of F ^- , Cl ^- , Br ^- , I ^- , NO ₃ ^- , N (CN) ₂ ^- , BF ₄ ^- , ClO ₄ ^- , RSO ₃ ^- , RCOO ^- an alkyl group or a phenyl group being) C1 to ^{_{C9, PF 6 -, (CF}} 3 SO 3 -) 2, (CF 2 CF 2 SO 3 -) 2, (CF 3 SO 3) 2 N -, CF 3 CF 2 (CF ^{_{3) 2 CO -, (CF}} 3 SO 2) 2 CH -, (CF3SO2) 3 C -, CF 3 CO 2 -, CH 3 CO 2 -), and at least one anion selected from the group comprising a combination thereof . ≪ / RTI >

The composition of the solid electrolyte complex and its ion conductivity will be described below.

The total amount of the sulfide-based solid electrolyte particles may be 50.0 to 99.9 wt%, and the amount of the organic liquid electrolyte may be 0.1 to 50.0 wt% based on 100 wt% of the solid electrolyte complex.

Also, the total number of the sulfide-based solid electrolyte particles may be 50.0 to 99.9 mol%, and the amount of the organic liquid electrolyte may be 0.1 to 50.0 mol% based on 100 mol% of the solid electrolyte complex.

On the other hand, the ionic conductivity of the solid electrolyte complex may be ¹ × 10 ^-4 to 5 × 10 ^-2 S / cm at room temperature (25 ° C.).

In another embodiment of the present invention, there is provided a method for producing a sulfide-based solid electrolyte, comprising the steps of: preparing a sulfide-based solid electrolyte powder; Preparing an organic liquid electrolyte; And mixing the sulfide-based solid electrolyte powder and the organic liquid electrolyte to obtain a solid electrolyte complex in powder form.

The step of mixing the sulfide-based solid electrolyte powder and the organic liquid electrolyte to obtain a solid electrolyte complex in powder form will now be described.

The mixing may be performed using any one of ball-mixing and manual-mixing.

Mixing the sulfide-based solid electrolyte powder and the organic liquid electrolyte to obtain a solid electrolyte complex in powder form; Thereafter, pelletizing the obtained solid electrolyte complex to obtain a solid electrolyte complex in the form of a pellet may be further included.

Wherein the step of preparing the sulfide-based solid electrolyte powder comprises the step of preparing a powder of a compound represented by the following formula (3) by using any one of a milling method, a melt quenching method and a liquid phase method: Powder. ≪ / RTI >

Li ₂ SP ₂ S ₅ -M _a S _x

In the above Formula 3, M, B, Al, Ga, In, Si, Ge, Sn, Pb, As, Sb, Bi, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, , Mo, Tc, Ru, Rh, Pd, Ag, Hf, Ta, or W, 0? A? 6,

Preparing the organic liquid electrolyte may include preparing a substance in which the metal salt is dissociated in the ion conductive organic solvent, an ion conductive liquid, or a mixture thereof.

According to another embodiment of the present invention, a plurality of electrode active material particles; A plurality of sulfide-based solid electrolyte particles; Wherein the plurality of electrode active material particles and the plurality of sulfide-based solid electrolyte particles are uniformly distributed and the organic liquid electrolyte is distributed in a gap between the respective particles, to provide.

Specifically, the plurality of sulfide-based solid electrolyte particles are contained in an amount of 20 to 70% by weight, the organic liquid electrolyte is contained in an amount of 2 to 7% by weight based on 100% by weight of the composite electrode, It may be included as the remainder.

And the plurality of electrode active material particles. (Li), a lithium metal oxide, a carbonaceous material, an oxide, silicon (Si), tin (Sn), germanium (Ge), sulfur (S), derivatives thereof, And at least one electrode active material particle selected from the group consisting of

The composite electrode may further include a plurality of conductive material particles. The description of the case is as follows.

The conductive particles may be included in an amount of 0.5 to 6 parts by weight based on 100 parts by weight of the composite electrode.

The plurality of conductive material particles may comprise at least one conductive material particle selected from the group consisting of super P, activated carbon, carbon black, and graphene. have.

In another embodiment of the present invention, cathode; And an electrolyte, wherein the electrolyte is a solid electrolyte complex according to any one of the foregoing.

Any one of the positive electrode and the negative electrode may be formed of at least one selected from the group consisting of lithium (Li), a lithium metal-based oxide, a carbonaceous material, an oxide, silicon (Si), tin (Sn), germanium S), a derivative thereof, and a mixture thereof.

In another embodiment of the present invention, cathode; And an electrolyte, wherein any one of the anode and the cathode is a composite electrode of any one of the foregoing.

The solid electrolyte complex according to one embodiment of the present invention is in the form of powder in which the excellent ionic conductivity of the organic liquid electrolyte and the excellent safety of the sulfide-based solid electrolyte are simultaneously taken and the interface between them is stably maintained. Chemical performance and durability.

The method for producing the solid electrolyte complex according to another embodiment of the present invention can contribute to mass production of the solid electrolyte complex having the above excellent characteristics by simply mixing.

Since the composite electrode according to another embodiment of the present invention is formed by combining a plurality of sulfide-based solid electrolyte particles and an organic liquid electrolyte with an electrode active material, advantages of the plurality of sulfide-based solid electrolytes (that is, Risk safety) and the advantages of the organic liquid electrolyte (i.e., stable interface formation with the electrode active material particles).

The pre-solid battery according to another embodiment of the present invention can improve the electrochemical performance and durability by taking advantage of each of the liquid electrolyte and the solid electrolyte by including the solid electrolyte complex or the composite electrode.

FIG. 1 schematically shows an electrode layer including a solid electrolyte complex according to an embodiment of the present invention.
Fig. 2 schematically shows an electrode layer including sulfide-based solid electrolyte particles.
3 to 7 are photographs of various organic solvents immediately after and 24 hours after the introduction of the solid electrolyte samples according to one embodiment of the present invention, respectively.
FIGS. 8 to 13 show the results of measuring the impedance for each of the solid electrolyte samples according to an embodiment of the present invention after forming them into pellets.
Figs. Ray diffraction analysis results of the solid electrolyte samples according to one embodiment of the present invention.
19 shows an electrochemical window for solid electrolyte samples according to an embodiment of the present invention.
FIGS. 20 to 23 show results of analysis according to the cyclic voltammetry method for each cell to which the solid electrolyte samples according to the embodiment of the present invention are applied.
24 to 29 show results of measurement of impedance for each cell to which solid electrolyte samples according to an embodiment of the present invention are applied.
30 to 34 show results of X-ray diffraction analysis of each cell to which solid electrolyte samples according to an embodiment of the present invention are applied.
FIGS. 36 to 39 show the results of performing analysis by the cyclic voltammetry method on all solid-state cells according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail. However, it should be understood that the present invention is not limited thereto, and the present invention is only defined by the scope of the following claims.

In one embodiment of the present invention, a plurality of sulfide-based solid electrolyte particles; And an organic liquid electrolyte distributed in a gap between the plurality of sulfide-based solid electrolyte particles, wherein the solid electrolyte complex is in powder form.

This is a combination of a solid electrolyte and an organic liquid electrolyte. 1) The interface between each material in the composite is stably maintained. 2) The advantages of the organic liquid electrolyte and the solid electrolyte are obtained. 3) 4) a solid electrolyte complex in the form of a powder that can offset the disadvantages.

1) Generally, since the organic liquid electrolyte is polar and the solid electrolyte is reactive with a polar material, the interface between them is unstable and difficult to be complexed. On the other hand, in the case of the solid electrolyte complex provided in one embodiment of the present invention, since the organic liquid electrolyte is stably distributed in the pores between the plurality of sulfide-based solid electrolyte particles, it is suitable for application to all solid batteries Do.

To this end, the organic liquid electrolyte in the solid electrolyte complex may be a material having little reactivity with the plurality of sulfide-based solid electrolyte particles and having excellent thermal stability.

2) Specifically, the whole solid battery including such a solid electrolyte layer can take advantage of the plurality of sulfide-based solid electrolyte particles and the organic liquid electrolyte as follows.

The plurality of sulfide-based solid electrolyte particles in the solid electrolyte complex are oxide-based materials generally used as a solid electrolyte (for example, Li _x La _y TiO ₃ , Li ₇ La ₃ Zr ₂ O ₁₂ ). Therefore, it is possible to make intimate contact between particles even by cold pressing alone, and this characteristic contributes to excellent initial conductivity of the entire solid battery.

Further, the organic liquid electrolyte in the solid electrolyte complex is distributed in the pores between the plurality of sulfide-based solid electrolyte particles, thereby providing an additional ion transfer pathway other than the plurality of sulfide-based solid electrolyte particles.

3) Further, the plurality of sulfide-based solid electrolyte particles offset a potential danger of leakage, ignition, explosion, and the like caused by the organic liquid electrolyte, and the organic liquid electrolyte contains the sulfide-based solid electrolyte particles Lt; RTI ID = 0.0 > interfacial instability < / RTI >

4) In addition, the solid electrolyte complex is in the form of powder and can be stably maintained in the form of pelletizing, unlike ordinary solid electrolytes, and the whole solid battery including the solid electrolyte layer as the solid electrolyte layer can be electrochemically Stability can be ensured.

Hereinafter, the solid electrolyte complex to be provided in one embodiment of the present invention will be described in more detail. In the examples and experimental examples thereof, the advantage of the solid electrolyte complex can be directly confirmed.

First, the plurality of sulfide-based solid electrolyte particles will be described as follows.

The plurality of sulfide-based solid electrolyte particles may include a plurality of sulfide-based solid electrolyte particles having high conductivity (for example,> 10 ^-4 S / cm) at room temperature. For example, a plurality of lithium sulfide Based solid electrolyte particles, a plurality of sodium sulfide based solid electrolyte particles, or a mixture thereof.

In this regard, the lithium sulfide-based material or the sodium sulfide-based material may be an oxide-based material (for example, Li _x La _y TiO ₃ , Li ₇ La ₃ Zr ₂ O ₁₂ And the like). Therefore, as described above, it is possible to make intimate contact between particles even by cold pressing alone, and such characteristics can contribute to excellent initial conductivity of the entire solid battery.

Here, the lithium sulfide-based solid electrolyte particles may be represented by the following general formula (1).

Li _a PM _b S _c X _d

In the above Formula 1, M, B, Al, Ga, In, Si, Ge, Sn, Pb, As, Sb, Bi, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, , Mo, Tc, Ru, Rh, Pd, Ag, Hf, Ta or W, X = F, Cl, Br, or I and 0? A? 6, 0? B? 6, 0? , 0? D? 6.

Independently, the sodium sulfide-based solid electrolyte particle may be represented by the following formula (2).

???????? Na _a PM _b S _c X _d ?????

In the above Formula 2, M, B, Al, Ga, In, Si, Ge, Sn, Pb, As, Sb, Bi, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, , Mo, Tc, Ru, Rh, Pd, Ag, Hf, Ta or W, X = F, Cl, Br, or I and 0? A? 6, 0? B? 6, 0? , 0? D? 6.

On the other hand, the plurality of sulfide-based solid electrolyte particles may be a plurality of crystalline sulfide-based solid electrolyte particles, a plurality of amorphous sulfide-based solid electrolyte particles, or a mixture thereof.

That is, the plurality of sulfide-based solid electrolyte particles may be composed only of crystalline particles or only of amorphous particles, but may be a mixture of crystalline particles and amorphous particles.

The description of the organic liquid electrolyte is as follows.

As described above, the organic liquid electrolyte is a material having little reactivity with the plurality of sulfide-based solid electrolyte particles and excellent in thermal stability. The organic liquid electrolyte is distributed in the pores between the plurality of sulfide-based solid electrolyte particles, Is not particularly limited as long as it is a substance capable of providing the above.

For example, the organic liquid electrolyte may be a substance in which a metal salt is dissociated in an ion conductive organic solvent, an ion conductive liquid, or a mixture thereof.

Specifically, the molar ratio of the ion conductive organic solvent to the metal salt in the ion-conductive organic solvent dissociated from the metal salt (the number of moles of the ion conductive organic solvent: the number of moles of the metal salt) is 1: 0.5 to 1: 5 .

That is, the substance in which the metal salt is dissociated into the ion conductive organic solvent may be one in which the metal salt is dissociated in the ion conductive organic solvent so as to satisfy the defined molar ratio range.

If the metal salt is excessively dissolved in the organic solvent so as to exceed the above-defined range, the metal salt can not dissolve anymore and is precipitated, resulting in the formation of a nonuniform liquid electrolyte. On the other hand, when a small amount of the metal salt is dissociated into the organic solvent below the defined range, the ion conductivity of the liquid electrolyte is lowered and the reactivity with the solid electrolyte is increased.

In this case, the metal salt in the substance in which the metal salt is dissociated into the ion conductive organic solvent is not particularly limited as long as it is a metal salt that can dissociate into the ion conductive organic solvent.

For example, the metal salt may be lithium hexafluorophosphate, lithium tetrafluoroborate, lithium hexafluoroacetate, lithium perchlorate, lithium tetrachloroaluminate, lithium bis oxalate borate, lithium trifluoromethanesulfonylimide (LiN (C _x F _{2x + 1} SO ₂ ) (C _y F _{2y + 1} SO ₂ ) (where x and y are natural numbers), sodium hexafluorophosphate, sodium tetrafluoroborate, sodium hexafluoroantimonide, Sodium chloride, sodium iodide, each derivative thereof, or a mixture thereof.

Independently, the ion conductive organic solvent in the material in which the metal salt is dissociated into the ion conductive organic solvent is not particularly limited as long as it is capable of dissociating the metal salt and is ion conductive. For example, it may be selected from a cyclic carbonate solvent, a glyme solvent, and an ether solvent.

Specifically, when the ion conductive organic solvent is used for the carbonate-based daily use, it is preferable to use ethylene carbonate, propylene carbonate, g-butylrolactone, Can be every day.

In the case where the ion conductive organic solvent is used for the glyme series daily, it may be a nitrile solvent such as acetonitrile, succinonitrile, adiponitrile, sebaconitrile, etc., For example, ethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, or a combination thereof.

When the ion conductive organic solvent is used for an ether system, it may be a hydrofluoroether, a dimethylether or a combination thereof.

On the other hand, the ion conductive liquid is not particularly limited as long as it is an ion conductive liquid material containing at least one cation and at least one anion, and examples thereof include ammonium (Ammonium), imidazolium, The present invention relates to a process for the preparation of a compound of formula (I) or a salt thereof, wherein the compound is selected from the group consisting of oxazolium, piperidinium, pyrazinium, pyrazolium, pyridazinium, pyridinium, pyrimidinium, pyrrolidinium), pyrrolidine titanium (Pyrrolinium), blood rolryum (Pyrrolium), triazolium (triazolium), and at least one cation selected from the group comprising a combination thereof, and F ^-, Cl ^-, Br ^-, I ^{-, _{NO 3 -, N (CN)}} 2 -, BF 4 -, ClO 4 -, RSO 3 -, RCOO - ( wherein R is an alkyl group or a phenyl C1 to ^{_{C9), PF 6 -, (}} CF 3 SO 3 -) _{2, (CF 2 CF 2 SO} 3 -) 2, (CF 3 SO 3) 2 N -, CF 3 CF 2 (CF 3) 2 CO -, (CF 3 SO 2) 2 CH -, (CF3SO2) 3 C ^- , CF ₃ CO ₂ ^- , CH ₃ CO ₂ ^- ), and their And at least one anion selected from the group consisting of combinations thereof.

The composition of the solid electrolyte complex and its ion conductivity will be described below.

The total amount of the sulfide-based solid electrolyte particles may be 50.0 to 99.9 wt%, and the amount of the organic liquid electrolyte may be 0.1 wt% to 50.0 wt% based on 100 wt% of the solid electrolyte complex.

If a plurality of sulfide-based solid electrolytes in the solid electrolyte complex are contained in an excess amount exceeding the above-defined range, there is a problem that the characteristics of the desired solid electrolyte complex are not exhibited because a relatively small amount of the organic liquid electrolyte is involved. Alternatively, when a plurality of sulfide-based solid electrolytes in the solid electrolyte complex are contained in a small amount below the defined range, relatively large amounts of the organic liquid electrolyte are required to be contained in an excessive amount, The organic liquid electrolyte may overflow during the pressing process.

Also, the total number of the sulfide-based solid electrolyte particles may be 50.0 to 99.9 mol%, and the amount of the organic liquid electrolyte may be 0.1 to 50.0 mol% based on 100 mol% of the solid electrolyte complex. The reason for limiting the content of each component based on 100 mol% of the solid electrolyte complex is that the content of each component is limited based on 100 wt% of the solid electrolyte complex.

Meanwhile, the ionic conductivity of the solid electrolyte complex may be ¹ × 10 ^-4 to 5 × 10 ^-2 S / cm at room temperature (25 ° C.).

This corresponds to a higher ionic conductivity than the generally known sulfide-based solid electrolytes (Li ₃ PS ₄ at 25 캜, 1 x 10 ^-3 S / cm). As described above, the above-described sulfide-based solid electrolyte particles alone have a limited contact property between particles.

However, in the case of the solid electrolyte complex, since the organic liquid electrolyte is located in the gap between the plurality of sulfide-based solid electrolyte particles, it is possible to further provide an ion transfer path, and as a result, the ion conductivity of the sulfide- Ionic conductivity.

In another embodiment of the present invention, there is provided a method for producing a sulfide-based solid electrolyte, comprising the steps of: preparing a sulfide-based solid electrolyte powder; Preparing an organic liquid electrolyte; And mixing the sulfide-based solid electrolyte powder and the organic liquid electrolyte to obtain a solid electrolyte complex in powder form.

As described above, it is generally difficult to produce an electrolyte in which a solid electrolyte and a liquid electrolyte are hybridized. However, the method of manufacturing the solid electrolyte complex is merely a process of mixing the sulfide-based solid electrolyte powder and the organic liquid electrolyte Whereby a powder in the form of a composite of these substances can be obtained.

For this, the organic liquid electrolyte may be a material having little reactivity with the sulfide-based solid electrolyte powder and having excellent thermal stability. Further, by controlling the mixing ratio of each of the raw materials (that is, the organic liquid electrolyte and the sulfide-based solid electrolyte powder), the electrochemical stability of the finally obtained solid electrolyte complex can be secured.

Hereinafter, a method for producing the solid electrolyte complex provided in one embodiment of the present invention will be described in detail. However, the description of the finally obtained solid electrolyte complex is as described above and is omitted.

The step of mixing the sulfide-based solid electrolyte powder and the organic liquid electrolyte to obtain a solid electrolyte complex in powder form will now be described.

In the mixing process, the organic liquid electrolyte can be permeated into the voids between the plurality of particles forming the sulfide-based solid electrolyte powder, and the respective raw materials can be contacted while maintaining a stable interface with each other, The solid electrolyte complex can be an electrochemically stable material.

At this time, as the organic liquid electrolyte is evenly distributed in the pores, the finally obtained solid electrolyte complex can form a stable interface, and an additional ion transfer path other than the plurality of sulfide-based solid electrolyte particles can be formed by the organic liquid electrolyte As described above.

For this purpose, the mixing can be performed by a method capable of uniformly dispersing the respective raw materials. For example, it can be performed using any one of ball-mixing and manual-mixing.

Mixing the sulfide-based solid electrolyte powder and the organic liquid electrolyte to obtain a solid electrolyte complex in powder form; Thereafter, pelletizing the obtained solid electrolyte complex to obtain a solid electrolyte complex in the form of a pellet may be further included.

As described above, a solid electrolyte generally has a characteristic that it is hard to realize in the form of a dense pellet which hardly contains pores even when pressed. On the other hand, the plurality of sulfide-based solid electrolyte particles contained in the solid electrolyte complex obtained in the powder form obtained is an oxide-based material (for example, Li_xLa_yTiO₃, Li₇La₃Zr₂O₁₂ And the organic liquid electrolyte is located in the gap between the plurality of sulfide-based solid electrolyte particles, so that it is easy to be pelletized.

On the other hand, the step of preparing the sulfide-based solid electrolyte powder can be carried out by using any one of the milling method, the melt quenching method and the liquid phase method, Or a solid electrolyte powder.

Li ₂ SP ₂ S ₅ -M _a S _x

In Formula 3, 0? A? 6 and 0? X? 6.

Further, the step of preparing the organic liquid electrolyte may include preparing a substance in which the metal salt is dissociated in the ion conductive organic solvent, an ion conductive liquid, or a mixture thereof.

When preparing a material in which the metal salt is dissociated into the ion conductive organic solvent with the organic liquid electrolyte, the molar ratio of the ion conductive organic solvent to the metal salt (the number of moles of the ion conductive organic solvent: the number of moles of the metal salt) 1: 5, and the reason for such a mole ratio limitation is as described above.

Also, the ion conductive organic solvent, the metal salt, and the ion conductive liquid may be respectively selected from the above-mentioned materials.

According to another embodiment of the present invention, a plurality of electrode active material particles; A plurality of sulfide-based solid electrolyte particles; Wherein the plurality of electrode active material particles and the plurality of sulfide-based solid electrolyte particles are uniformly distributed and the organic liquid electrolyte is distributed in a gap between the respective particles, to provide.

A typical pre-solid electrolyte electrode is a composite in which a solid electrolyte and an active material are combined (in some cases, conductive particles are more complex). 2 schematically shows an electrode consisting of a plurality of sulfide-based solid electrolyte particles and an active material unlike the composite electrode, in which active material particles 30 are formed on the pores between the plurality of sulfide-based solid electrolyte particles 10 However, it can be seen that the empty space is not filled.

On the other hand, since the composite electrode has a form in which the plurality of sulfide-based solid electrolyte particles and the organic liquid electrolyte are stably combined with the electrode active material, the advantages of the plurality of sulfide-based solid electrolytes (that is, (That is, a stable interface with the electrode active material particles) and advantages of the organic liquid electrolyte (i.e., stable interface formation with the electrode active material particles).

1 schematically shows the composite electrode, in which active material particles 30 are distributed in a gap between the plurality of sulfide-based solid electrolyte particles 10, and the remaining void space is filled with an organic liquid electrolyte 30).

Therefore, when the entire solid-state cell to which the present invention is applied is a lithium secondary battery, even if an active material having poor interfacial characteristics is used with the plurality of sulfide-based solid electrolyte particles per se, stable contact with the active material The cell to which it is applied is not only electrochemically stable but also its performance (for example, initial ion conductivity) can be improved.

Further, even if an active material having a large volume change due to reversible charging and discharging of lithium is used, the organic liquid electrolyte has an additional ion transfer path other than the plurality of sulfide-based solid electrolyte particles. Therefore, Even when discharging is repeated, deterioration of ion conductivity can be minimized.

Further, the plurality of sulfide-based solid electrolyte particles offset the potential danger of leakage, ignition, explosion, etc., of the organic liquid electrolyte, and the organic liquid electrolyte is formed by the plurality of sulfide-based solid electrolyte particles The interface instability can be attenuated.

The description of the plurality of sulfide-based solid electrolyte particles and the organic liquid electrolyte is as described above, and the characteristics of the composite electrode except for the above are described below.

Specifically, the plurality of sulfide-based solid electrolyte particles are contained in an amount of 20 to 70% by weight, the organic liquid electrolyte is contained in an amount of 2 to 7% by weight based on 100% by weight of the composite electrode, It may be included as the remainder.

If a plurality of sulfide-based solid electrolytes in the solid electrolyte complex are contained in an excess amount exceeding the above-defined range, there is a problem that the characteristics of the desired solid electrolyte complex are not exhibited because a relatively small amount of the organic liquid electrolyte is involved.

Alternatively, when a plurality of sulfide-based solid electrolytes in the solid electrolyte complex are contained in a small amount below the defined range, relatively large amounts of the organic liquid electrolyte are required to be contained in an excessive amount, The organic liquid electrolyte may overflow during the pressing process.

And the plurality of electrode active material particles. Although not particularly limited, a compound capable of reversible intercalation and deintercalation of lithium (a lithiated intercalation compound) can be used.

That is, even if an active material having a large volume change due to the reversible charging and discharging of lithium in the electrode active material is used, the solid electrolyte complex may further include additional ion transfer paths other than the plurality of sulfide-based solid electrolyte particles The deterioration of the ion conductivity can be minimized even if the battery is repeatedly charged and discharged.

For example, the electrode may be formed of at least one selected from the group consisting of lithium (Li), a lithium metal oxide, a carbonaceous material, an oxide, silicon (Si), tin (Sn), germanium (Ge) And a mixture thereof. The electrode active material particles may be at least one selected from the group consisting of a metal oxide, a metal oxide, and a mixture thereof.

The composite electrode may further include a plurality of conductive material particles. The description of the case is as follows.

The conductive particles may be contained in an amount of 0.5 to 10 parts by weight per 100 parts by weight of the composite electrode.

If more than 10 parts by weight of the plurality of conductive material particles is contained in 100 parts by weight of the composite electrode as a whole, side reactions at a high voltage of 4 V or higher can be accelerated and energy mass density and energy density density are reduced . On the other hand, if it is further contained in an amount of less than 0.5 part by weight, the amount thereof is too small and the effect of imparting conductivity to the composite electrode is insignificant.

The plurality of conductive material particles are not particularly limited as long as they are conductive particles. However, the conductive material particles are not particularly limited as long as they are conductive particles in the group including super p, activated carbon, carbon black, and graphene And may include one or more selected conductive particles.

In another embodiment of the present invention, cathode; And an electrolyte, wherein the electrolyte is a solid electrolyte complex according to any one of the foregoing.

By including the solid electrolyte complex according to any one of the above-described methods, it is possible that the positive electrode or the active material contained in the negative electrode has excellent contact and interfacial characteristics and is electrochemically stable and has improved performance. Further, Which corresponds to an all-solid-state battery in which the performance deterioration can be prevented even when charging and discharging are repeated.

The electrode active material contained in any one of the positive electrode and the negative electrode is not particularly limited, but a compound capable of reversible intercalation and deintercalation of lithium (a lithiated intercalation compound) can be used .

That is, even if an active material having a large volume change due to the reversible charging and discharging of lithium in the electrode active material is used, the solid electrolyte complex may further include additional ion transfer paths other than the plurality of sulfide-based solid electrolyte particles The deterioration of the ion conductivity can be minimized even if the battery is repeatedly charged and discharged.

For example, the electrode may include a lithium metal oxide, a carbonaceous material, an oxide, silicon (Si), tin (Sn), germanium (Ge), sulfur (S), derivatives thereof, And at least one electrode active material selected from the group consisting of

In the case of the lithium metal-based oxide, at least one of cobalt, manganese, nickel, or a composite oxide of a metal and lithium may be used. Specific examples thereof include compounds represented by any one of the following formulas . Li _a A _{1 - b} R _b D ₂ wherein, in the formula, 0.90? A? 1.8 and 0? B? 0.5; Li _a E _{1 - b} R _b O _{2 - c} D _c , wherein 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, and 0 ≤ c ≤ 0.05; LiE _{2 - b} R _b O _{4 - c} D _{c where} 0? B? 0.5, 0? C? 0.05; Li _a Ni _{1 -b- c} Co _b R _c D _{α where} 0.90 ≦ a ≦ 1.8, 0 ≦ b ≦ 0.5, 0 ≦ c ≦ 0.05, and 0 <α ≦ 2; Li _a Ni _{1 - b - c} Co _b R _c O _{2 - ?} Z _{? Wherein} 0.90? A? 1.8, 0? B? 0.5, 0? C? 0.05 and 0 <? Li _a Ni _{1 -b- c} Co _b R _c O _{2 - ?} Z ₂ wherein 0.90? A? 1.8, 0? B? 0.5, 0? C? 0.05, and 0 <? Li _a Ni _{1 -b- c} Mn _b R _c D _? Wherein, in the formula, 0.90? A? 1.8, 0? B? 0.5, 0? C? 0.05, and 0 <? Li _a Ni _{1 -b- c} Mn _b R _c O _{2 - ?} Z _{? Where the} 0.90? A? 1.8, 0? B? 0.5, 0? C? 0.05 and 0 <? Li _a Ni _1-bc Mn _b R _c O _2-α Z ₂ wherein 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.5, 0 ≤ c ≤ 0.05, and 0 <α <2; Li _a Ni _b E _c G _d O ₂ wherein 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, and 0.001 ≤ d ≤ 0.1; Li _a Ni _b Co _c Mn _d GeO ₂ wherein 0.90 ≤ a ≤ 1.8, 0 ≤ b ≤ 0.9, 0 ≤ c ≤ 0.5, 0 ≤ d ≤ 0.5, and 0.001 ≤ e ≤ 0.1; Li _a NiG _b O ₂ (in the above formula, 0.90? A? 1.8 and 0.001? B? 0.1); Li _a CoG _b O ₂ (in the above formula, 0.90? A? 1.8 and 0.001? B? 0.1); Li _a MnG _b O ₂ (in the above formula, 0.90? A? 1.8 and 0.001? B? 0.1); Li _a Mn ₂ G _b O ₄ (in the above formula, 0.90? A? 1.8 and 0.001? B? 0.1); QO _2; QS ₂ ; LiQS ₂ ; V ₂ O ₅ ; LiV ₂ O ₅ ; LiTO ₂ ; LiNiVO _4; Li _(3-f) J ₂ (PO ₄ ) ₃ (0? F? 2); Li _(3-f) Fe ₂ (PO ₄ ) ₃ (0? F? 2); And LiFePO _4.

In the above formula, A is Ni, Co, Mn or a combination thereof; R is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element or a combination thereof; D is O, F, S, P or a combination thereof; E is Co, Mn or a combination thereof; Z is F, S, P or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V or a combination thereof; Q is Ti, Mo, Mn or a combination thereof; T is Cr, V, Fe, Sc, Y or a combination thereof; J is V, Cr, Mn, Co, Ni, Cu or a combination thereof.

Of course, a compound having a coating layer on the surface of the compound may be used, or a compound having a coating layer may be mixed with the compound. The coating layer may comprise, as a coating element compound, an oxide, a hydroxide of a coating element, an oxyhydroxide of a coating element, an oxycarbonate of a coating element, or a hydroxycarbonate of a coating element. The compound constituting these coating layers may be amorphous or crystalline. The coating layer may contain Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr or a mixture thereof. The coating layer forming step may be carried out by any of coating methods such as spray coating, dipping, and the like without adversely affecting the physical properties of the cathode active material by using these elements in the above compound. It is a content that can be well understood by people engaged in the field, so detailed explanation will be omitted.

On the other hand, typical examples of the carbon-based material include crystalline carbon, amorphous carbon, or a combination thereof. Examples of the crystalline carbon include graphite such as natural graphite or artificial graphite in the form of amorphous, plate-like, flake, spherical or fibrous type. Examples of the amorphous carbon include soft carbon (soft carbon) Or hard carbon, mesophase pitch carbide, fired coke, and the like.

Hereinafter, preferred embodiments of the present invention and test examples therefor will be described. However, the following examples are only a preferred embodiment of the present invention, and the present invention is not limited to the following examples.

Test Example  1: Evaluation of Reactivity of Liquid Electrolyte and Solid Electrolyte

Generally, in order to evaluate the reactivity between the liquid electrolyte and the solid electrolyte, a solid electrolyte was put in an organic solvent that can be used for the production of a liquid electrolyte or a liquid electrolyte, and the resultant was stored for 24 hours and observed for changes.

Specifically, Li ₃ PS ₄ (hereinafter referred to as LPS) and (Li ₁₀ GeP ₂ S ₁₂ (hereinafter referred to as LGPS)), which are crystalline sulfide-based solid electrolytes, were used as the solid electrolyte.

As the liquid electrolyte, tetraethylene glycol dimethyl ether, which is a Glyme-based organic solvent, is mixed with lithium bis-trifluloromethanesulfonimide (LiN (CF ₃ SO ₂ ) (CF ₃ SO ₂ , hereinafter referred to as LiTFSA), or an organic solvent which is not mixed with the metal salt itself.

Specifically, in the case of the organic liquid electrolyte, a solution (hereinafter referred to as LiG 3) in which the molar ratio of the glimpse solvent to the metal salt is 1: 1 (metal salt: glimpic solvent), the molar ratio is 1: 4 : Glimpic solvent) (hereinafter referred to as Li (G3) 4) was used.

In the case of the organic solvent not mixed with the metal salt, dimethyl sulfoxide (DMF), acetonitrile (AN), dimethyl formamide, and 1-methyl-3-pyrrolidinol (1-methyl-3-pyrrolidinol, NMP) was used.

Each of the organic liquid electrolyte and the organic solvent was variously combined with each of the solid electrolytes to confirm their reactivity.

FIG. 3 is a photograph of photographs taken immediately after and 24 hours after the injection of each of the solid electrolytes into dimethyl sulfoxide (DMF) in the organic solvent.

FIG. 4 shows photographs taken immediately after and 24 hours after the injection of each of the solid electrolytes into acetonitrile (AN) in the organic solvent.

FIG. 5 shows photographs taken immediately after and 24 hours after the injection of each of the solid electrolytes into dimethyl formamide in the organic solvent.

FIG. 6 is a photograph showing the photographs taken immediately after and 24 hours after each of the solid electrolytes were charged into LiG3 among the organic liquid electrolytes.

FIG. 7 is a photograph showing the photographs of Li (G3) 4 of the organic liquid electrolyte immediately after and 24 hours after the injection of each of the solid electrolytes.

In Figures 3 to 7, It is confirmed that LPS in the solid electrolyte reacts in all cases except LiG3, and the color of the solution changes with time. Among the solid electrolytes, LGPS also reacts in all cases except LiG3, but the degree of color change of the solution is smaller than that of LPS. Thus, it is inferred that the reactivity of the organic liquid electrolyte or the organic solvent is lower than that of LPS.

Example  1: Preparation of solid electrolyte complex

According to one embodiment and another embodiment of the present invention, a solid electrolyte complex was prepared by using a sulfide-based solid electrolyte and an organic liquid electrolyte as raw materials. The detailed manufacturing process is as follows.

(1) Selection of sulfide-based solid electrolyte

Li ₃ PS ₄ (hereinafter referred to as LPS) and (Li ₁₀ GeP ₂ S ₁₂ (hereinafter referred to as LGPS) were selected as crystalline sulphide-based solid electrolytes in the same manner as in Test Example 1.

(2) Production of organic liquid electrolyte

As in the case of the organic liquid electrolyte used in Test Example 1, LiTFSA, which is a metal salt, was added to tetraethylene glycol dimethyl ether as a Glyme series organic solvent at a molar ratio of 1: 1 and 1: 4 (metal salt: Organic solvent) were mixed to prepare LiG3 and Li (G3) 4, respectively.

In addition, LiTFSA, which is a metal salt, was added to the acetonitrile in a molar ratio of 1: 2 (metal salt: nitrile) using acetonitrile as a nitrile-based solvent instead of the Glyme- Organic solvent) (hereinafter referred to as Li (AN) 2) was prepared.

(3) Preparation of solid electrolyte complex

The solid electrolyte selected in the above (1) and the organic liquid electrolyte prepared in the above (2) were mixed at various ratios to obtain solid electrolyte complex samples 1 to 6.

Solid electrolyte complex sample 1

Specifically, the two materials were uniformly mixed through a ball-mill so that the molar ratio of the LPS to the LiG3 was 9: 1 (LPS: LiG3), and the total mass of the LiG3 and the LPS was 250 mg (Performed at 2000 rpm for 2 minutes and 30 seconds using 5 mm zirconia balls). The solid electrolyte complex thus obtained is referred to as sample 1.

Solid electrolyte complex sample 2

The two materials were mixed with a ball mill (G3) 4 so that the molar ratio of LPS to Li (G3) 4 was 9: 1 (LPS: Li (G3) 4) (5 mm zirconia balls at 2000 rpm for 2 minutes and 30 seconds) through a ball-mill. The solid electrolyte complex thus obtained is referred to as sample 2.

Solid electrolyte complex sample 3

The two materials were evenly mixed through a ball-mill so that the molar ratio of LPS to LiG3 was 7: 3 (LPS: LiG3) and the total mass of LiG3 and LPS was 250 mg (5 mm Zirconia balls at 2000 rpm for 2 minutes and 30 seconds). The solid electrolyte complex thus obtained is referred to as Sample 3.

Solid electrolyte complex sample 4

The two materials were evenly mixed through a ball-mill so that the molar ratio of LGPS to LiG3 was 9: 1 (LGPS: LiG3), and the total mass of LiG3 and LGPS was 250 mg 5 mm zirconia balls at 2000 rpm for 2 minutes 30 seconds). The solid electrolyte complex thus obtained is referred to as Sample 4.

Solid electrolyte complex sample 5

The two materials were evenly mixed through a ball-mill so that the molar ratio of LPS to LiAN2 was 9: 1 (LPS: LiAN2), and the total mass of LiAN2 and LGPS was 250 mg 5 mm zirconia balls at 2000 rpm for 2 minutes and 30 seconds). The solid electrolyte complex thus obtained is referred to as Sample 5.

Solid electrolyte complex sample 6

The two materials were evenly mixed through a ball-mill such that the molar ratio of LGPS to LiAN2 was 9: 1 (LGPS: LiAN2) and the total mass of LiAN2 and LGPS was 250 mg (5 mm Zirconia balls at 2000 rpm for 2 minutes and 30 seconds). The solid electrolyte complex thus obtained is referred to as Sample 6.

The samples 1 to 6 can be distinguished from those according to the present invention by the following test examples.

Test Example  2: Example  Evaluation of physical properties of each solid electrolyte complex prepared in 1

Each of the solid electrolyte composites prepared in Example 1 has a powder shape which is not different from a normal solid electrolyte in appearance. Even if pelletized, there is no difference in appearance from a conventional solid electrolyte pellet.

Specifically, FIGS. 8 to 9 are SEM photographs of Sample 1 composited so that the molar ratio of LPS: LiG3 is 9: 1, and FIGS. 10 to 11 are SEM photographs of LPS which is an uncomplexed solid electrolyte.

8 to 9 and 10 to 11, it is observed that there is little difference in physical characteristics. That is, it can be seen that Sample 1 is in the form of powder like LPS which is a non-complexed solid electrolyte.

More specifically, in contrast to FIGS. 9 and 11, it is observed that Sample 1 is in a better state of rolling than LPS, which is an uncomplexed solid electrolyte. This is inferred from the fact that, in the case of the sample 1, the liquid electrolyte filled the void between the plurality of LPS particles well.

12 to 13 are SEM photographs of Sample 4 which is composed such that the molar ratio of LGPS: LiG3 is 9: 1, and FIGS. 14 to 15 are SEM photographs of LGPS which is a non-combined solid electrolyte.

12 to 13 and Figs. 14 to 15, it is observed that there is little difference in physical characteristics. On the contrary, in the case of Sample 4, it is in the form of a finely crushed powder, which is inferred to be caused by a process of mixing the liquid electrolyte and ball milling.

When each of these powders was cold-pressed and pelletized under the condition of applying a pressure of 360 MPa at 30 DEG C, a larger difference was observed.

16 to 17 are SEM photographs of a sample 1 pellet compounded such that the molar ratio of LPS: LiG3 is 9: 1, and Figs. 18 to 19 are SEM photographs of the LPS pellets, which are the non-complex solid electrolytes.

16-17 and 18-19, the surface of the Sample 1 pellet has much less cracks than the LPS pellet, which is an uncomplexed solid electrolyte. Since such a crack is formed in the process of pelletization, it is deduced that the organic liquid electrolyte contained in the sample (#) inhibits the formation of cracks.

20 to 21 are SEM photographs of Sample 4 pellets composited such that the molar ratio of LGPS: LiG3 is 9: 1, and FIGS. 22 to 23 are SEM photographs of LGPS pellets, which are non-complex solid electrolytes.

20-21 and 22-23, the surface of the sample (4) pellet has much less cracks than the LGPS pellet, which is an uncomplexed solid electrolyte, and the same reasoning as the previous reasoning It is possible.

Test Example  3: Example  Evaluation of Chemical and Electrochemical Properties of Each Solid Electrolyte Complex Prepared

The chemical stability and electrochemical properties of each solid electrolyte complex prepared in Example 1 were analyzed by impedance analysis, X-ray diffraction (XRD) analysis, and cyclic voltammetry (CV) Stability was confirmed.

(1) Impedance analysis

 150 mg of each of the solid electrolyte complexes (Samples 1 to 6) prepared in Example 1 was placed in a cylindrical mold of f13 mm and pressed at a pressure of 370 MPa to form pellets. The impedance was measured for each of the pellets, 29.

Specifically, Figure 24 is for Sample 1, Figure 25 is for Sample 2, Figure 26 is for Sample 3, Figure 27 is for Sample 4, Figure 28 is for Sample 5, Is for sample 6.

Through Figures 24 to 29, the chemical stability of each sample can be evaluated. As a result, samples with increasing resistance values over time are chemically unstable.

First, in the case of Fig. 24 (Sample 1), Fig. 26 (Sample 3), and Fig. 27 (Sample 4), the resistance value does not change with time after 3 hours after the temperature equilibrium is set. As a result, it can be concluded that LPS and LGPS form a chemically stable complex with LiG3, respectively.

Specifically, in contrast to FIG. 24 (Sample 1) and FIG. 26 (Sample 3) concerning the solid electrolyte complex including LPS and LiG 3, it can be estimated that the chemical stability is maintained even when the content of LiG 3 in the solid electrolyte complex is increased have.

On the other hand, in FIG. 25 (sample 2) and FIG. 28 (sample 5), the resistance value tends to increase with time. It can be concluded that Li (G3) 4 and LiAN2 did not form a chemically stable complex with LPS, respectively.

On the other hand, in FIG. 29 (Sample 6), the resistance value does not change with time after three hours after the temperature equilibrium is set, and LGPS and LiAN2 can be evaluated as forming a chemically stable complex. This is related to the fact that LGPS has less reactivity with organic liquid electrolyte than LPS, as confirmed in Test Example 1.

(2) X-ray diffraction (X- ray diffraction , XRD ) analysis

For each solid electrolyte complex prepared in Example 1, a D8-Bruker Advance diffractometer equipped with Cu K radiation (1.54056 A was used. All XRD patterns were measured at 40 kV and 40 mA in continuous scanning mode at 1.5 ° min ^{- 1.} The results are shown in Figs. 30 to 34.

Specifically, FIG. 30 relates to Sample 1, FIG. 31 relates to Sample 2, FIG. 32 relates to Sample 4, FIG. 33 relates to Sample 5, and FIG. 30 through 34, the chemical stability of each of the samples can be confirmed again.

First, the X-ray diffraction analysis results of the chemically stable solid electrolyte complexes LPS and LiG3 composite, LGPS and LiG3 composite, and LGPS and LiAN2 composite are shown in FIGS. 30, 32 and 34. FIG.

In Figures 30, 32 and 34, the chemically stable solid electrolyte complexes exhibit the same X-ray diffraction pattern as the uncomplexed solid electrolyte. Thus, it can be seen that the chemically safe solid electrolyte complexes have the same structure as the non-complexed solid electrolyte, and the organic liquid electrolyte is stably distributed in the space between the sulfide-based solid electrolyte particles.

On the other hand, the results of the X-ray diffraction analysis of the complex of LPS and Li (G3) 4, which are chemically insecure solid electrolyte complexes, and the complex of LPS and LiAN2 are shown in FIG. 31 and FIG.

In FIGS. 31 and 33, the chemically unstable solid electrolyte complexes exhibited different X-ray diffraction patterns over time from the uncomplexed solid electrolytes. The different crystal structure appears as a result of the reaction between the sulfide-based solid electrolyte particles and the organic liquid electrolyte to form the chemically unstable solid electrolyte complexes. Further, it can be deduced that the ionic conductivity value will be lowered due to chemical instability.

(3) circulation In the cyclic voltammetry (CV)  Analysis by

Figures 35 (a) to (d) show the electrochemical window of each sample prepared in Example 1. Specifically, 1.5 to 5.0 V vs. The cyclic voltammetry was performed at a Li / Li + potential of 0.2 mVs ^-1 . Through this, the electrochemical stability of the Example 1 samples according to the voltage range can be evaluated.

Example  2: Preparation of composite electrodes and their preparation All solids  Manufacture of batteries

According to one embodiment and another embodiment of the present invention, a composite electrode is prepared by using an electrode active material, a sulfide-based solid electrolyte, and an organic liquid electrolyte as raw materials. In addition, all of the composite electrodes were used as positive electrodes to prepare all of the solid battery samples 1 to 4. The detailed process is as follows.

All solids  Battery Sample 1

10 parts by weight of LiG3 was added to 100 parts by weight of a mixed powder prepared by uniformly mixing sulfur, activated carbon, and solid electrolyte (LPS) in a ball milling (sulfur: activated carbon: solid electrolyte: solid electrolyte = 25: 25: 50 mass ratio) Lt; / RTI &gt;

10 mg of the positive electrode material was placed on the pellet of a separately prepared solid electrolyte (LPS), and 60 mg of the negative electrode active material was placed on the opposite side of the pellet on which the positive electrode active material was placed using a lithium-indium (Li) To produce a sample 1 of the entire solid battery.

All solids  Battery Sample 2

A solid electrolyte (LGPS), liquid electrolyte (LiG3), and LiCoO _{2 -} a _{- LiCoO 2: LGPS: LiG3 =} 70: 27: was mixed in a weight ratio of 3 was used as the anode material.

10 mg of the positive electrode material was placed on the pellet of a separately prepared solid electrolyte (LPS-LGPS Bilayer), and then lithium-indium (Li-In) alloy was used as the negative electrode active material and the opposite side of the pellet 60 mg and pressed at a pressure of 370 MPa to prepare a sample 2 of the entire solid battery.

The solid electrolyte pellet of the LPS-LGPS bilayer type was formed into a pellet by cold pressing with 120 mg of LGPS under a pressure of 120 MPa. Then, 30 mg of LPS was placed on the pellet, and a pressure of 120 MPa LPS-LGPS double layer type solid electrolyte pellet which is formed by pelletization by cold-pressing.

All solids  Battery Sample 3

A solid electrolyte (LGPS), liquid electrolyte (LiG3), and Al ₂ O with a _third coating LiCoO _{2 -} coated with Al ₂ O _{3 -} a mixture (the _- (LiCoO _2: 99.95: weight ratio of Al ₂ O ₃ 0.05) LiCoO ₂ : LGPS: LiG 3 = 70: 27: 3) was used as a positive electrode material.

10 mg of the positive electrode material was placed on a solid electrolyte (LPS-LGPS Bilayer) pellet prepared separately, and 60 mg of lithium-indium (Li-In) alloy was placed on the opposite side of the pellet on which the positive electrode active material was placed And pressed at a pressure of 370 MPa to prepare Sample 3 of all solid batteries.

The solid electrolyte pellets in the form of LPS-LGPS Bilayer were those prepared in the same manner as the all solid-state battery samples 3.

All solids  Battery Sample 4

A solid electrolyte (LGPS), conductive material (Super P), liquid electrolyte (LiG3) and LiFePO _{4 -} mixture of the _{(-: -} LGPS LiFePO _4: conductive material: LiG3 = 27: 20:: 3 ratio by weight of 3) as a positive electrode material Respectively.

10 mg of the positive electrode material was placed on a solid electrolyte (LPS-LGPS Bilayer) pellet prepared separately, and 60 mg of lithium-indium (Li-In) alloy was placed on the opposite side of the pellet on which the positive electrode active material was placed And pressed at a pressure of 370 MPa to prepare Sample 4 as a whole solid battery.

The solid electrolyte pellets in the form of LPS-LGPS Bilayer were those prepared in the same manner as the all solid-state battery samples 3.

Test Example  4: Example  2 &lt; / RTI &gt; All solids  Evaluation of electrochemical characteristics of batteries

For each of the pre-solid batteries prepared in Example 2, analysis by cyclic voltammetry was performed in various voltage ranges. To prepare for this, all solid-state batteries were fabricated using a cathode material that did not contain a liquid electrolyte, followed by analysis by cyclic voltammetry.

36 and 37 show the results of the charge / discharge of lithium by applying a current of 320 mA g ^-1 over the voltage method of 1.0 to 3.0 V according to the cyclic voltammetry method for the entire solid-state battery sample 1 and the entire solid- It is about repeated results.

In Figures 36 and 37, S-AC-LPS + LiG3 refers to all solid-state battery samples 1. In addition, S-AC-LPS refers to all-solid-state cells prepared in the same manner as Sample 1, except that LiG3 is not added to the anode material, unlike sample 1 of the entire solid-state battery.

36 and 37, in the case of the anode in which the organic liquid electrolyte, the solid electrolyte and the active material are combined with each other than the anode containing only the solid electrolyte and the active material, the contact loss due to the volume change of the sulfur, And further provides an additional lithium ion migration path, so that a better performance is exhibited.

38 is a graph showing the results of the charge and discharge of lithium by applying a current of 14 mA g ^-1 on all solid-state battery samples 2 and 3 and all the solid-state batteries to be compared with each other in a voltage method of 3.0 to 4.3 V according to a cyclic- And the results are repeated.

 In FIG. 38, all solid-state battery samples 2 are denoted as b-LCO / LGPS + LiG3, and all solid-state battery samples 3 denoted ALD-LCO / LGPS + LiG3. In addition, all the solid-state batteries represented by b-LCO / LGPS are produced in the same manner as Sample 2, except that LiG3 is not added to the anode material, unlike Sample 2 of the entire solid-state battery.

38, it can be confirmed that the electrochemical performance of the entire solid battery is excellently exhibited in the case of the anode in which the organic liquid electrolyte, the solid electrolyte and the active material are combined rather than the anode containing only the solid electrolyte and the active material. This is because the liquid electrolyte in the anode of all solid-state battery samples 2 and 3 not only provides an additional lithium ion path other than the sulfide-based solid electrolyte particles, but also reduces the chemical instability between the sulfide-based solid electrolyte particles and the oxide-based cathode active material to be. It is also confirmed that the electrochemical performance is further improved when the surface of the oxide-based cathode active material is coated with Al ₂ O ₃ .

FIG. 39 is a graph showing the relationship between the total charge and the discharge time of the lithium ion battery by applying a current of 15 mA g ^{-1 on} the pre-solid electrolyte battery sample 4 and the pre- It is about the result.

In Figure 39, what is designated as b-LFP / LGPS + LiG3 relates to all solid-state battery sample 4. [ Also, all solid-state batteries represented by b-LFP / LGPS are produced in the same manner as Sample 4, except that LiG3 is not added to the anode material, unlike Sample 4,

It can also be seen from FIG. 39 that the electrochemical performance of the entire solid battery is excellently exhibited in the case of the anode in which the organic liquid electrolyte, the solid electrolyte and the active material are combined, compared with the anode containing only the solid electrolyte and the active material. This is because the liquid electrolyte in the anode of the all solid-state battery sample 4 not only provides an additional lithium ion path other than the sulfide-based solid electrolyte particles, but also reduces the chemical instability between the sulfide-based solid electrolyte particles and the oxide-based cathode active material.

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 as defined by the following claims. As will be understood by those skilled in the art. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

10: Sulfide-based solid electrolyte particles
20: active material
30: Organic liquid electrolyte

Claims (26)

A plurality of sulfide-based solid electrolyte particles; And
An organic liquid electrolyte,
Wherein the organic liquid electrolyte is formed in a complex form distributed in a gap between the plurality of solid electrolyte particles,
Ray diffraction (XRD) analysis by Cu K?, The same X-ray diffraction pattern as the plurality of solid electrolyte particles not complexed with the organic liquid electrolyte ,
Solid electrolyte complex.
The method according to claim 1,
The plurality of sulfide-based solid electrolyte particles may include,
A plurality of lithium sulfide-based solid electrolyte particles, a plurality of sodium sulfide-based solid electrolyte particles, or a mixture thereof,
Solid electrolyte complex.
3. The method of claim 2,
The lithium-based sulfide-based solid electrolyte particles can be obtained by,
Wherein R &lt; 1 &gt;
Solid electrolyte complex:
[Chemical Formula 1]
Li _a PM _b S _c X _d
In Formula 1,
M, B, Al, Ga, In, Si, Ge, Sn, Pb, Sb, Bi, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Rh, Pd, Ag, Hf, Ta, or W,
X = F, Cl, Br, or I,
0 <a? 6, 0? B? 6, 0 <c? 6, 0?
3. The method of claim 2,
The sodium sulfide-based solid electrolyte particles can be obtained by,
Wherein R &lt; 1 &gt;
Solid electrolyte complex:
(2)
Na _a PM _b S _c X _d
In Formula 2,
M, B, Al, Ga, In, Si, Ge, Sn, Pb, Sb, Bi, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Rh, Pd, Ag, Hf, Ta, or W,
X = F, Cl, Br, or I,
0 <a? 6, 0? B? 6, 0 <c? 6, 0?
3. The method of claim 2,
The plurality of sulfide-based solid electrolyte particles may include,
A plurality of crystalline sulfide-based solid electrolyte particles, a plurality of amorphous sulfide-based solid electrolyte particles, or a mixture thereof,
Solid electrolyte complex.
The method according to claim 1,
Wherein the organic liquid electrolyte comprises:
A substance in which the metal salt is dissociated into an ion conductive organic solvent, an ion conductive liquid, or a mixture thereof,
Solid electrolyte complex.
The method according to claim 6,
The molar ratio of the ion conductive organic solvent to the metal salt in the ion-conductive organic solvent dissociated from the metal salt (the number of moles of the ion conductive organic solvent: the number of moles of the metal salt)
1: 0.5 to 1: 5.
Solid electrolyte complex.
The method according to claim 6,
The metal salt in the substance in which the metal salt is dissociated into the ion conductive organic solvent,
Lithium hexafluorophosphate, lithium tetrafluoroborate, lithium hexafluoroacetate, lithium perchlorate, lithium tetrachloroaluminate, lithium bis oxalate borate, lithium trifluoromethanesulfonylimide (LiN (C _x F _{2x +1)} SO ₂ ) (C _y F _{2y + 1} SO ₂ ) wherein x and y are natural numbers, sodium hexafluorophosphate, sodium tetrafluoroborate, sodium hexafluoroantimonide, sodium perchlorate, sodium chloride, sodium iodide , Each derivative thereof, or a mixture thereof.
Solid electrolyte complex.
The method according to claim 6,
The ion conductive organic solvent in the material in which the metal salt is dissociated into the ion conductive organic solvent,
A cyclic carbonate solvent, a glyme solvent, and an ether solvent.
Solid electrolyte complex.
The method according to claim 6,
The ion conductive liquid may include,
The compounds of formula (I) are preferably selected from the group consisting of: Ammonium, Imidazolium, Oxazolium, Piperidinium, Pyrazinium, Pyrazolium, Pyridazinium, Pyridinium At least one cation selected from the group consisting of pyridinium, pyrimidinium, pyrrolidinium, pyrrolinium, pyrrolium, triazolium, and combinations thereof, and ^{F -, Cl -, Br -} , I -, NO 3 -, N (CN) 2 -, BF 4 -, ClO 4 -, RSO 3 -, RCOO - ( wherein R is an alkyl group or a phenyl C1 to C9 ^{_{), PF 6 -, (CF}} 3 SO 3 -) 2, (CF 2 CF 2 SO 3 -) 2, (CF 3 SO 3) 2 N -, CF 3 CF 2 (CF 3) 2 CO -, (CF At least one anion selected from the group consisting of: (CH ₃ ) ₂ CH ₂ ^- , (CF ₃ SO ₂ ) ₃ C ^- , CF ₃ CO ₂ ^- , CH ₃ CO ₂ ^-
Solid electrolyte complex.
The method according to claim 1,
With respect to 100 wt% of the solid electrolyte complex,
Wherein the plurality of sulfide-based solid electrolyte particles are contained in an amount of 50.0 to 99.9 wt%, and the organic liquid electrolyte is contained in an amount of 0.1 to 50.0 wt%
Solid electrolyte complex.
The method according to claim 1,
The ionic conductivity of the solid electrolyte complex is,
¹ x 10 &lt; ^-4 &gt; to 5 x 10 &lt; ^-2 &gt; S / cm at room temperature (25 &
Solid electrolyte complex.
Preparing a sulfide-based solid electrolyte powder;
Preparing an organic liquid electrolyte; And
And mixing the sulfide-based solid electrolyte powder and the organic liquid electrolyte to obtain a solid electrolyte complex in powder form,
Mixing the sulfide-based solid electrolyte powder and the organic liquid electrolyte to obtain a solid electrolyte complex in powder form; and subjecting the mixture to ball-mixing or manual-mixing And the organic liquid electrolyte is distributed in a gap between a plurality of sulfide-based solid electrolyte particles constituting the sulfide-based solid electrolyte powder to form a composite,
Ray diffraction (XRD) analysis by Cu K?, The same X-ray diffraction pattern as the plurality of solid electrolyte particles not complexed with the organic liquid electrolyte sign,
A method for producing a solid electrolyte complex.
delete 14. The method of claim 13,
Mixing the sulfide-based solid electrolyte powder and the organic liquid electrolyte to obtain a solid electrolyte complex in powder form; Since the,
And pelletizing the obtained solid electrolyte complex to obtain a solid electrolyte complex in the form of a pellet.
A method for producing a solid electrolyte complex.
14. The method of claim 13,
Preparing a sulfide-based solid electrolyte powder,
Wherein the powder of the compound represented by the following formula (3) is prepared from the sulfide-based solid electrolyte powder by any one of a milling method, a melt quenching method, and a liquid phase method.
A method for producing a solid electrolyte complex.
(3)
Li ₂ SP ₂ S ₅ -M _a S _x
In Formula 3,
M, B, Al, Ga, In, Si, Ge, Sn, Pb, As, Sb, Bi, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Ru, Rh, Pd, Ag, Hf, Ta, or W,
0? A? 6,
0? X? 6.
14. The method of claim 13,
Preparing an organic liquid electrolyte,
Preparing a substance in which the metal salt has been dissociated into an ion conductive organic solvent, an ion conductive liquid, or a mixture thereof.
A method for producing a solid electrolyte complex.
A plurality of electrode active material particles;
A plurality of sulfide-based solid electrolyte particles; And
An organic liquid electrolyte,
Wherein the organic liquid electrolyte is distributed in a gap between the plurality of solid electrolyte particles, and the composite and the organic liquid electrolyte are uniformly distributed composite electrodes,
Ray diffraction (XRD) analysis by Cu K?, The same X-ray diffraction pattern as the plurality of solid electrolyte particles not complexed with the organic liquid electrolyte sign,
Composite electrode.
19. The method of claim 18,
With respect to 100 wt% of the composite electrode as a whole,
Wherein the plurality of sulfide-based solid electrolyte particles are contained in an amount of 20 to 70 wt%, the organic liquid electrolyte is contained in an amount of 2 to 7 wt%, and the plurality of electrode active material particles are included as a remainder.
Composite electrode.
19. The method of claim 18,
And the plurality of electrode active material particles.
(Li), a lithium metal oxide, a carbonaceous material, an oxide, silicon (Si), tin (Sn), germanium (Ge), sulfur (S), derivatives thereof, And at least one electrode active material particle selected from the group comprising &lt; RTI ID = 0.0 &gt;
Composite electrode.
19. The method of claim 18,
And a plurality of conductive material particles;
Composite electrode.
22. The method of claim 21,
Wherein the conductive particles are contained in an amount of 0.5 to 6 parts by weight based on 100 parts by weight of the composite electrode.
Composite electrode.
22. The method of claim 21,
Wherein the plurality of conductive material particles comprise:
And at least one conductive material particle selected from the group consisting of super p, activated carbon, carbon black, and graphene.
Composite electrode.
anode;
cathode; And
An electrolyte;
The electrolyte,
The solid electrolyte complex according to any one of claims 1 to 12,
All solid state batteries.
25. The method of claim 24,
Wherein either one of the positive electrode and the negative electrode is a positive electrode,
(Li), a lithium metal oxide, a carbonaceous material, an oxide, silicon (Si), tin (Sn), germanium (Ge), sulfur (S), derivatives thereof, And at least one electrode active material selected from the group consisting of:
All solid state batteries.
anode;
cathode; And
An electrolyte;
Wherein either one of the positive electrode and the negative electrode is a positive electrode,
A composite electrode according to any one of claims 18 to 23,
All solid state batteries.

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