JP6373417B2 - Solid electrolyte - Google Patents

Description

  The present invention relates to a solid electrolyte.

In recent years, there has been an increasing demand for lithium ion secondary batteries used in personal digital assistants, portable electronic devices, small household power storage devices, motorcycles powered by motors, electric vehicles, hybrid electric vehicles, and the like.
In the lithium ion secondary battery, an organic electrolytic solution is used as an electrolyte. Although organic electrolytes exhibit high ionic conductivity, they are liquid and flammable, so there are concerns about safety such as leakage and ignition.

  As a method for ensuring the safety of a lithium ion secondary battery, an all-solid secondary battery using an inorganic solid electrolyte instead of an organic electrolyte has been studied. However, in general, inorganic solid electrolytes have lower ionic conductivity than organic electrolytes, and it has been difficult to put all solid secondary batteries into practical use.

As an inorganic solid electrolyte, for example, lithium ion conductive ceramics based on Li ₃ N have been reported. However, since this ceramic has a low decomposition voltage, it could not be used for an all-solid-state secondary battery operating at 3 V or higher.

Non-Patent Document 1 discloses a solid electrolyte made of sulfide-based crystallized glass exhibiting high lithium ion conductivity. However, the electrolyte described in Non-Patent Document 1 is industrially disadvantageous because it requires a large amount of expensive germanium.
Moreover, in patent document 1, the ion conductivity improves to 1.0 * 10 < ^-3 > S / cm in the glass sulfide solid electrolyte material which contains the ionic conductor which has ortho composition, and LiI, and has a glass transition point. Is disclosed.

JP 2012-48973 A

N. Kamaya et al., Nature Materials 10, 682 (2011).

  An object of the present invention is to provide a solid electrolyte having higher ionic conductivity suitable for an all-solid secondary battery.

According to the present invention, the following solid electrolyte and the like are provided.
1. At least one alkali metal element, phosphorus (P) element, sulfur (S) element, and at least one halogen element selected from I, Cl, Br and F, and a differential scanning calorimetry (drying) Solid electrolyte glass having two exothermic peaks separated from each other in the range of 150 ° C. to 350 ° C. at a temperature rising rate of 10 ° C./min, 20 to 600 ° C. in a nitrogen atmosphere.
2. 2. The solid electrolyte glass according to 1, wherein a temperature difference between peak top positions of the two exothermic peaks is 20 ° C. or higher and 150 ° C. or lower.
3. 2. The solid electrolyte glass according to 1, wherein a temperature difference between peak top positions of the two exothermic peaks is 30 ° C. or higher and 130 ° C. or lower.
4). Solid electrolyte glass in any one of 1-3 which has a composition shown by following formula (1).
_{L a M b P c S d} X e ... (1)
(In the formula, L represents an alkali metal, M represents one or more elements selected from B, Al, Si, Ge, As, Se, Sn, Sb, Te, Pb and Bi, and X represents I, Cl, One or more halogen elements selected from Br and F are shown.
a to e each satisfy the following formula.
0 <a ≦ 12, 0 ≦ b ≦ 0.2, c = 1, 0 <d ≦ 9, 0 <e ≦ 9)
5. The manufacturing method of the solid electrolyte glass in any one of 1-4 which uses the following (A), (B) and (C) as a raw material.
(A) an alkali metal sulfide (B) M _'m S compounds represented by _{n (C) M "w X} y compound represented by (wherein, M' include B, Al, Si, P or Ge M ″ represents Li, Na, B, Al, Si, P, S, Ge, As, Se, Sn, Sb, Te, Pb or Bi, and X represents F, Cl, Br or I. w Represents an integer of 1 to 2, and m, n, and y represent integers of 1 to 10.)
6). 6. Production of solid electrolyte glass according to 5, comprising reacting raw materials (A) and (B), and then adding raw material (C) to react with the reactants of raw materials (A) and (B). Method.
7). The manufacturing method of the solid electrolyte glass of 5 or 6 including the process made to react in the atmosphere whose oxygen concentration is 19-21%.
8). Further, (D) a _Li 2 SO ₃ are added to 5 mol% as the component manufacturing method of the solid electrolyte glass according to any one of 5-7.
9. The solid electrolyte glass obtained by the manufacturing method of the solid electrolyte glass in any one of said 5-8.
10. A solid electrolyte glass ceramic obtained by heat-treating the solid electrolyte glass according to any one of 1 to 5 and 9 at a temperature between the two exothermic peaks.
11. 11. The solid electrolyte glass ceramic according to 10, having an ionic conductivity of 1 × 10 ⁻³ S / cm or more.
12 A positive electrode mixture comprising at least one of the solid electrolyte glass according to any one of 1 to 5 and 9, and the solid electrolyte glass ceramic according to 10 or 11, and a positive electrode active material.
13. A negative electrode mixture comprising at least one of the solid electrolyte glass according to any one of 1 to 5 and 9, and the solid electrolyte glass ceramic according to 10 or 11, and a negative electrode active material.
14 An all solid state battery comprising a solid electrolyte layer containing at least one of the solid electrolyte glass according to any one of 1 to 5 and 9 and the solid electrolyte glass ceramic according to 10 or 11.
15. All-solid-state battery provided with the positive electrode layer which consists of said 12 positive electrode compound materials.
16. All-solid-state battery provided with the negative electrode layer which consists of said 13 negative electrode compound materials.
17. 150 ° C. observed in differential scanning calorimetry (temperature increase rate 10 ° C./min, 20 to 600 ° C. in a dry nitrogen atmosphere) of the solid electrolyte glass contained in the solid electrolyte layer, the positive electrode mixture or the negative electrode mixture The all-solid-state battery in any one of 14-16 obtained by heat-processing in the temperature between exothermic peak temperature of the two independent exothermic peaks of the range of -350 degreeC.

  According to the present invention, a solid electrolyte having high ion conductivity can be provided.

It is a figure which shows the differential thermothermal gravimetric measurement result of the solid electrolyte glass and solid electrolyte glass ceramic which were synthesize | combined in Example 1. It is a figure which shows the differential thermothermal gravimetric measurement result of the solid electrolyte glass synthesize | combined in Examples 1-3 and Comparative Examples 1-3. 10 is a schematic view of a production apparatus for solid electrolyte glass used in Example 9. FIG.

A. Solid electrolyte glass The solid electrolyte glass of the present invention is a precursor of a solid electrolyte glass ceramic described later, and includes at least one of alkali metal elements, phosphorus (P) element, sulfur (S) element, I, Cl, It is a sulfide-based glass containing at least one or more halogen elements selected from Br and F.

And in differential scanning calorimetry, it has two exothermic peaks separated from each other in the range of 150 ° C. to 350 ° C.
Here, the measurement conditions for differential scanning calorimetry are 20 to 600 ° C. at a temperature rising rate of 10 ° C./min in a dry nitrogen atmosphere. For example, using a differential thermal-thermogravimetric measuring device (TGA / DSC1 manufactured by METTLER TOLEDO) or a differential scanning calorimeter (Diamond DSC manufactured by Perkin Elmer), the solid electrolyte can be measured at about 20 mg.
“Two exothermic peaks separated from each other” means two peaks without an overlapping portion or 20% or less of the maximum value (height) of each peak between two peaks even when there is an overlapping portion. This means that there is a value area.
The height of the peak means the height with respect to the baseline. The base line is a line obtained by approximating a range of 75 to 150 ° C. to a straight line and extrapolating. However, when the peak due to crystallization or the bending due to glass transition is at 75 to 150 ° C., the other range is approximated to a straight line, and the extrapolated straight line is taken as the baseline.

The present invention has been found that when a sulfide-based glass having two separated exothermic peaks is heated to a temperature between the peaks and converted into a glass ceramic, the ionic conductivity of the resulting glass ceramic is improved. is there.
For example, when the electrolyte of Patent Document 1 is subjected to thermal analysis, there is only one exothermic peak in the above temperature range. Thus, when there is only one exothermic peak, or when there are two exothermic peaks as shown in the comparative example described later, two peaks are present, the peak-to-peak temperature Even if the glass ceramic is formed at a temperature near the peak, the ionic conductivity of the obtained glass ceramic is lower than that of the solid electrolyte ceramic of the present invention.

In the glass ceramic, it is effective to perform a heat treatment that generates a metastable phase in order to increase the ionic conductivity. However, when there is only one exothermic peak or when two peaks overlap, It is difficult to produce mainly a metastable phase.
In the solid electrolyte glass of the present invention, the ionic conductivity is increased because the solid electrolyte glass can be maintained for a certain period of time at a temperature between two exothermic peaks, that is, between a metastable phase peak and a stable phase peak.

In the present application, the term “glass” means that a peak due to a crystal is not observed as a result of X-ray diffraction measurement, or a peak intensity is low even if a peak due to a crystal is observed (a target is mainly amorphous). Means quality). On the other hand, glass ceramic means a case where a peak due to a crystal is observed as a result of X-ray diffraction measurement. The glass ceramic may contain an amorphous part. That is, the glass ceramic includes a mixture of glass and glass ceramic.
In the present application, the solid electrolyte before the heat treatment is denoted as solid electrolyte glass, and the solid electrolyte after the heat treatment is denoted as solid electrolyte glass ceramic.

The solid electrolyte glass of the present invention preferably has, for example, each element except oxygen having a composition represented by the following formula (1). It is more preferable that all elements contained in the solid electrolyte glass have a composition represented by the following formula (1).
_{L a M b P c S d} X e ... (1)
(In the formula, L represents an alkali metal, M represents one or more elements selected from B, Al, Si, Ge, As, Se, Sn, Sb, Te, Pb and Bi, and X represents I, Cl, One or more halogen elements selected from Br and F are shown.
a to e each satisfy the following formula.
0 <a ≦ 12, 0 ≦ b ≦ 0.2, c = 1, 0 <d ≦ 9, 0 <e ≦ 9)

The solid electrolyte glass of the present invention can be synthesized using, for example, the following raw materials (A), (B), and (C).
(A) an alkali metal sulfide (B) M _'m S compounds represented by _{n (C) M "w X} y compound represented by (wherein, M' is B, Al, Si, P, Ge, M ″ represents Li, Na, B, Al, Si, P, S, Ge, As, Se, Sn, Sb, Te, Pb, or Bi, X represents F, Cl, Br, or I. w represents 1. ) Represents an integer of ˜2, and m, n, and y represent integers of 1 to 10.)

Examples of the raw material (A) include Li ₂ S (lithium sulfide) and Na ₂ S (sodium sulfide). Of these, lithium sulfide is preferable.
Lithium sulfide can be used without particular limitation, but high purity is preferred. Lithium sulfide can be produced, for example, by the methods described in JP-A-7-330312, JP-A-9-283156, JP-A 2010-163356, and Japanese Patent Application No. 2009-233892.

Specifically, lithium hydroxide and hydrogen sulfide are reacted at 70 ° C. to 300 ° C. in a hydrocarbon-based organic solvent to produce lithium hydrosulfide, and then the reaction solution is dehydrosulfurized to form lithium sulfide. Can be synthesized (Japanese Patent Laid-Open No. 2010-163356).
In addition, lithium hydroxide and hydrogen sulfide are reacted at 10 ° C. to 100 ° C. in an aqueous solvent to produce lithium hydrosulfide, and then the reaction liquid is dehydrosulfurized to synthesize lithium sulfide (special feature). Application 2009-238952).

  The lithium sulfide preferably has a total lithium oxide lithium salt content of 0.15% by mass or less, more preferably 0.1% by mass or less, and a lithium N-methylaminobutyrate content. The content is preferably 0.15% by mass or less, more preferably 0.1% by mass or less. When the total content of the lithium salt of sulfur oxide is 0.15% by mass or less, the solid electrolyte obtained by the melt quenching method or the mechanical milling method becomes a glassy electrolyte (fully amorphous). On the other hand, when the total content of the lithium salt of sulfur oxide exceeds 0.15% by mass, the obtained electrolyte may become a crystallized product from the beginning.

  In addition, when the content of lithium N-methylaminobutyrate is 0.15% by mass or less, a deteriorated product of lithium N-methylaminobutyrate does not deteriorate the cycle performance of the lithium ion battery. When lithium sulfide with reduced impurities is used, a high ion conductive electrolyte can be obtained.

When lithium sulfide is produced based on the above-mentioned JP-A-7-330312 and JP-A-9-283156, it is preferable to purify the lithium sulfide because it contains a lithium salt of a sulfur oxide.
On the other hand, lithium sulfide produced by the method for producing lithium sulfide described in JP-A-2010-163356 may be used without purification because it contains a very small amount of sulfur oxide lithium salt or the like.
As a preferable purification method, for example, a purification method described in International Publication No. WO2005 / 40039 and the like can be mentioned. Specifically, the lithium sulfide obtained as described above is washed at a temperature of 100 ° C. or higher using an organic solvent.

As the raw material (B), P ₂ S ₃ (phosphorus trisulfide) _, P ₂ S ₅ (phosphorus pentasulfide), SiS ₂ (silicon sulfide), Al ₂ S ₃ (aluminum sulfide), GeS ₂ (germanium sulfide) ), B ₂ S ₃ (diarsenic trisulfide), or the like can be used. P ₂ S ₅ is preferable. In addition, you may use a raw material (B) in mixture of 2 or more types.
P ₂ S ₅ can be used without particular limitation as long as it is industrially manufactured and sold.

As the compound containing a halogen element _{(C), LiF, LiCl,} LiBr, LiI, BCl 3, BBr 3, BI 3, AlF 3, AlBr 3, AlI 3, AlCl 3, SiF 4, SiCl 4, SiCl 3, Si _{2 Cl 6, SiBr 4, SiBrCl} 3, SiBr 2 Cl 2, SiI 4, PF 3, PF 5, PCl 3, PCl 5, PBr 3, PI 3, P 2 Cl 4, P 2 I 4, SF 2, SF ₄ , SF ₆ , S ₂ F ₁₀ , SCl ₂ , S ₂ Cl ₂ , S ₂ Br ₂ , GeF ₄ , GeCl ₄ , GeBr ₄ , GeI ₄ , GeF ₂ , GeCl ₂ , GeBr ₂ , GeI ₂ , AsF ₃ , _{AsCl 3, AsBr 3, AsI 3} , AsF 5, SeF 4, SeF 6, SeCl 2, SeCl 4, Se 2 B _{2, SeBr 4, SnF 4,} SnCl 4, SnBr 4, SnI 4, SnF 2, SnCl 2, SnBr 2, SnI 2, SbF 3, SbCl 3, SbBr 3, SbI 3, SbF 5, SbCl 5, PbF 4, _{PbCl 4, PbF 2, PbCl 2} , PbBr 2, PbI 2, BiF 3, BiCl 3, BiBr 3, BiI 3, TeF 4, Te 2 F 10, TeF 6, TeCl 2, TeCl 4, TeBr 2, TeBr 4, TeI4 _, NaI, NaF, NaCl, NaBr, etc. are mentioned. Preferred is a compound in which M ″ is lithium or phosphorus. Specifically, LiCl, LiBr, LiI, PCl ₅ , PCl ₃ , PBr ₅ and PBr ₃ are preferred, and LiCl, LiBr, LiI and PBr ₃ are more preferred. It is.

In addition to the raw materials (A) to (C), a compound (vitrification accelerator) for reducing the glass transition temperature may be added as the raw material (D). Examples of vitrification promoters include Li ₃ PO ₄ , Li ₄ SiO ₄ , Li ₄ GeO ₄ , Li ₃ BO ₃ , Li ₃ AlO ₃ , Li ₃ CaO ₃ , Li ₃ InO _3, Na ₃ PO ₄ , Na Examples include inorganic compounds such as ₄ SiO ₄ , Na ₄ GeO ₄ , Na ₃ BO ₃ , Na ₃ AlO ₃ , Na ₃ CaO ₃ , and Na ₃ InO ₃ .

In addition to the raw materials (A) to (D), simple phosphorus (P), simple sulfur (S), silicon (Si), LiBO ₂ (lithium metaborate), LiAlO ₃ (lithium aluminate), Na ₂ S (sodium sulfide), NaBO ₂ (sodium metaborate), NaAlO ₃ (sodium aluminate), POCl ₃ , POBr _{3 and the} like can also be used.

The solid electrolyte glass of the present invention has a vitrification accelerator, a halogen compound containing oxygen, lithium sulfite in the examples, and the like. For example, in the following formula (1 ′) of each element containing oxygen: Having the composition shown.
_{L a M b P c S d} X e O f ... (1 ')
(In the formula, L represents an alkali metal, M represents one or more elements selected from B, Al, Si, Ge, As, Se, Sn, Sb, Te, Pb and Bi, and X represents I, Cl, One or more halogen elements selected from Br and F are shown.
a to e each satisfy the following formula.
0 <a ≦ 12, 0 ≦ b ≦ 0.2, c = 1, 0 <d ≦ 9, 0 <e ≦ 9, 0 <f ≦ 9)

The solid electrolyte glass of the present invention is a sulfide glass having the composition represented by the above formula (1), but the composition can be controlled by adjusting the blending ratio of the raw materials (A) to (D).
The mixing ratio of the components (A), (B), and (C) depends on whether M ″ of the component (C) is phosphorus or other than phosphorus.
When M ″ of component (C) is other than phosphorus, for example, the molar ratio of component (A) :( B) is 65:35 to 85:15, preferably (A) :( B) = 67: 33 83:17 (molar ratio), more preferably (A) :( B) = 68: 32-80: 20 (molar ratio), most preferably (A) :( B) = 75: 25 -79: 21 (molar ratio).
At this time, the ratio of the molar amount of (C) to the total molar amount of components (A) and (B) is preferably 50:50 to 99: 1, more preferably [(A) + ( B)] :( C) = 55: 45 to 97: 3 (molar ratio), more preferably [(A) + (B)] :( C) = 60: 40 to 96: 4 (molar ratio). Especially preferably, [(A) + (B)] :( C) = 70: 30 to 96: 4 (molar ratio).

When M ″ of component (C) is phosphorus, for example, the molar ratio of component (A) :( B) is 60:40 to 90:10, preferably (A) :( B) = 70: 30 To 90:10 (molar ratio), more preferably (A) :( B) = 72: 28 to 88:12 (molar ratio), and still more preferably (A) :( B) = 74: 26. To 86:14 (molar ratio), particularly preferably (A) :( B) = 75: 25 to 85:15 (molar ratio), most preferably component (A) is lithium sulfide, Component (B) diphosphorus pentasulfide, (A) :( B) = 77: 23 to 83:17 (molar ratio).
At this time, the ratio of the molar amount of (C) to the total molar amount of components (A) and (B) is preferably 50:50 to 99: 1, more preferably [(A) + ( B)] :( C) = 80: 20 to 98: 2 (molar ratio), more preferably [(A) + (B)] :( C) = 85: 15 to 98: 2 (molar ratio). Particularly preferably, [(A) + (B)] :( C) = 90: 10 to 98: 2.

The blending amount of the raw material (D) (vitrification accelerator) is preferably 1 to 10 mol%, particularly 1 to 5 mol%, based on the total of the raw materials (A), (B) and (C). It is preferable that
In addition, the solid electrolyte glass of this invention may consist of the said raw material (A)-(C) and the raw material (D) arbitrarily, and may consist only of these components. “Substantially” means that the composition is mainly composed of the raw materials (A) to (C) and optionally the raw material (D). For example, the raw materials (A) to (D) are the raw materials. It means 95% by weight or more or 98% by weight or more based on the whole.

The raw materials (A) to (C) and optionally the raw material (D) are mixed and vitrified by a melt quenching method, a mechanical milling method (MM method), a slurry method, a solid phase method, or the like. Solid electrolyte glass can be synthesized. Hereinafter, an example in which Li ₂ S is used as the raw material (A) and P ₂ S ₅ is used as the raw material (B) will be described for each method.

(A) Melting and quenching method The melting and quenching method is described, for example, in JP-A-6-279049 and WO2005 / 119706. Specifically, P ₂ S ₅ , Li ₂ S, and a halogen-containing compound (raw material (C)) mixed in a predetermined amount in a mortar and put into a pellet form are placed in a carbon-coated quartz tube and vacuum sealed To do. After reacting at a predetermined reaction temperature, the solid electrolyte glass is obtained by putting it in ice and rapidly cooling it.

The reaction temperature is preferably 400 ° C to 1000 ° C, more preferably 800 ° C to 900 ° C.
The reaction time is preferably 0.1 hour to 12 hours, more preferably 1 to 12 hours.
The quenching temperature of the reactant is usually 10 ° C. or less, preferably 0 ° C. or less, and the cooling rate is usually about 1 to 10,000 K / sec, preferably 10 to 10,000 K / sec.

(B) Mechanical milling method (MM method)
The MM method is described in, for example, JP-A-11-134937, JP-A-2004-348972, and JP-A-2004-348993.
Specifically, P ₂ S ₅ , Li ₂ S and raw material (C) are mixed in a predetermined amount in a mortar and reacted for a predetermined time using, for example, various ball mills or the like, thereby obtaining a solid electrolyte glass. .
The MM method using the above raw materials can be reacted at room temperature. Therefore, there is an advantage that a solid electrolyte glass having a charged composition can be obtained without thermal decomposition of the raw material.
In addition, the MM method has an advantage that it can be made into fine powder simultaneously with the production of the solid electrolyte glass.

Various types such as a rotating ball mill, a rolling ball mill, a vibrating ball mill, and a planetary ball mill can be used for the MM method.
As conditions for the MM method, for example, when a planetary ball mill is used, the rotational speed may be set to several tens to several hundreds of revolutions / minute, and the treatment may be performed for 0.5 hours to 100 hours.
Further, as described in JP 2010-90003 A, balls of a ball mill may be used by mixing balls having different diameters.
Further, as described in JP2009-110920A or JP2009-2111950, an organic solvent may be added to the raw material to form a slurry, and this slurry may be subjected to MM treatment.
Further, as described in JP 2010-30889 A, the temperature in the mill during MM processing may be adjusted.
It is preferable that the raw material temperature during the MM treatment be 60 ° C. or higher and 160 ° C. or lower.

(C) Slurry method The slurry method is described in WO2004 / 093099 and WO2009 / 047977.
Specifically, a solid electrolyte is obtained by reacting a predetermined amount of P ₂ S ₅ particles, Li ₂ S particles, and a raw material (C) in an organic solvent for a predetermined time.
The raw material (C) is preferably dissolved in an organic solvent or particles.

Here, as described in JP-A-2010-140893, in order to advance the reaction, the slurry containing the raw material may be reacted while being circulated between the bead mill and the reaction vessel.
Further, as described in WO2009 / 047977, when the raw material lithium sulfide is pulverized in advance, the reaction can proceed efficiently.
Further, as described in Japanese Patent Application No. 2010-270191, in order to increase the specific surface area of the raw material lithium sulfide, it is predetermined in a polar solvent (for example, methanol, diethyl carnate, acetonitrile) having a solubility parameter of 9.0 or more. You may soak for hours.

The reaction temperature is preferably 20 ° C. or higher and 80 ° C. or lower, more preferably 20 ° C. or higher and 60 ° C. or lower.
The reaction time is preferably 1 hour or longer and 16 hours or shorter, more preferably 2 hours or longer and 14 hours or shorter.

The amount of the organic solvent is preferably such that the raw materials P ₂ S ₅ , Li ₂ S and the raw material (C) become a solution or a slurry by the addition of the organic solvent. Usually, the amount of the raw material (total amount) added to 1 liter of the organic solvent is about 0.001 kg or more and 1 kg or less. Preferably they are 0.005 kg or more and 0.5 kg or less, Most preferably, they are 0.01 kg or more and 0.3 kg or less.

The organic solvent is not particularly limited, but an aprotic organic solvent is particularly preferable.
Examples of the aprotic organic solvent include an aprotic nonpolar organic solvent (for example, a hydrocarbon organic solvent), an aprotic polar organic compound (for example, an amide compound, a lactam compound, a urea compound, an organic sulfur compound, a ring). A formula organophosphorus compound or the like) can be suitably used as a single solvent or as a mixed solvent.

As the hydrocarbon organic solvent, a saturated hydrocarbon, an unsaturated hydrocarbon, or an aromatic hydrocarbon can be used.
Examples of the saturated hydrocarbon include hexane, pentane, 2-ethylhexane, heptane, decane, and cyclohexane.
Examples of the unsaturated hydrocarbon include hexene, heptene, cyclohexene and the like.
Aromatic hydrocarbons include toluene, xylene, decalin, 1,2,3,4-tetrahydronaphthalene and the like.
Of these, toluene and xylene are particularly preferable.

The hydrocarbon solvent is preferably dehydrated in advance. Specifically, the water content is preferably 100 ppm by weight or less, and particularly preferably 30 ppm by weight or less.
In addition, you may add another solvent to a hydrocarbon type solvent as needed. Specific examples include ketones such as acetone and methyl ethyl ketone, ethers such as tetrahydrofuran, alcohols such as ethanol and butanol, esters such as ethyl acetate, and halogenated hydrocarbons such as dichloromethane and chlorobenzene.

(D) Solid-phase method The solid-phase method is described in "HJ Deiseroth, et.al., Angew.Chem.Int.Ed.2008,47,755-758", for example. Specifically, P ₂ S ₅ , Li ₂ S and the raw material (C) are mixed in a predetermined amount in a mortar and heated at a temperature of 100 to 900 ° C. to obtain a solid electrolyte.

Manufacturing conditions such as temperature conditions, processing time, and charge for the melt quenching method, MM method, slurry method and solid phase method can be appropriately adjusted according to the equipment used.
As the method for producing the solid electrolyte glass, the MM method, the slurry method or the solid phase method is preferable. Since it can be produced at a low cost, the MM method and the slurry method are more preferable, and the slurry method is particularly preferable.

In any case of the melt quenching method, the MM method, the slurry method, and the solid phase method, the mixing order may be such that the composition of the final solid electrolyte glass is within the range described above. For example, in the case of the MM method, the raw material (A), the raw material (B), and the raw material (C) may be mixed and then milled. After the raw material (A) and the raw material (B) are milled, the raw material (C) may be added and further milled. Further, after milling LiBr and P ₂ S ₅ , Li ₂ S may be added and further milled; after milling the raw material (A) and the raw material (C), the raw material (B) may be added and further milled. Good. Furthermore, after mixing the raw material (A) and the raw material (C) and milling, and mixing the raw material (C) and the raw material (B), the milling process may be performed.

  In addition, when the mixing process is performed twice or more, two or more different methods may be combined. For example, the raw material (A) and the raw material (B) may be processed by mechanical milling, and then the raw material (C) may be mixed and processed by a solid phase method. The solid electrolyte glass may be manufactured by mixing the processed material, the raw material (B), and the raw material (C) subjected to a melt quenching process and performing a slurry method.

In the present invention, it is preferable to first react the raw materials (A) and (B), and then add the raw material (C) to react with the reactants of the raw materials (A) and (B). Thereby, the space between the two exothermic peaks can be made wider.
Moreover, it is preferable to include the process made to react in the atmosphere whose oxygen concentration is 19-21%. For example, enclosing dry air in a ball mill. Thereby, the space between the two exothermic peaks can be made wider.

In the solid electrolyte glass of the present invention, two exothermic peaks (crystallization peaks) separated from each other in the range of 150 ° C. to 350 ° C. are observed by differential scanning calorimetry as described above. The temperature difference between the peak top positions of the two exothermic peaks is preferably 20 ° C. or more and 150 ° C. or less, more preferably 30 ° C. or more and 130 ° C. or less, and further preferably 35 to 130 ° C., In particular, the temperature is preferably 40 to 120 ° C. As a result, the conditions of the heat treatment that causes only the metastable phase are more relaxed.
The peak top positions of the two exothermic peaks can be adjusted by, for example, the type of raw material, the blending ratio of each raw material, and the type of manufacturing method. As an example, after the electrolyte precursor is synthesized in advance using the raw material (A) and the raw material (B), the raw material (C) is added and further the synthesis treatment is performed, so that each peak top position is expanded. Further, the peak top position is expanded by performing each step in the presence of oxygen.

  The two crystallization peaks are preferably in the range of 170 ° C. or higher and 330 ° C. or lower, more preferably in the range of 175 ° C. or higher and 320 ° C. or lower, and particularly in the range of 180 ° C. or higher and 310 ° C. or lower. It is preferable.

B. Solid electrolyte glass ceramic The solid electrolyte glass ceramic of the present invention is obtained by heat-treating the above-described solid electrolyte glass of the present invention at a temperature between the two exothermic peaks described above.
The heat treatment temperature is preferably in the range not exceeding the exothermic peak (Tc2) on the high temperature side, preferably the peak temperature (Tc1) or higher (Tc + 30) ° C. or lower of the exothermic peak on the low temperature side, particularly (Tc1 + 5) ° C. or higher. A temperature of (Tc1 + 25) ° C. or lower is preferred.
As for the intensity of each peak before and after heat treatment, for the exothermic peak on the low temperature side, it is desirable that the intensity after the heat treatment is substantially zero relative to the peak intensity before the heat treatment, It is desirable to keep the strength of 70% or more. Thereby, a sufficient amount of metastable phase can be formed.

The heating time is preferably 0.005 minutes or more and 10 hours or less. More preferably, it is 0.005 minutes or more and 5 hours or less, and particularly preferably 0.01 minutes or more and 3 hours or less.
There is no specific specification for the temperature raising method. The temperature may be raised slowly to a predetermined temperature or heated rapidly.
Heating is preferably performed in an environment with a dew point of −40 ° C. or lower, more preferably in an environment with a dew point of −60 ° C. or lower. The atmospheric pressure during heating may be a normal pressure or a reduced pressure. The atmosphere may be in the air or an inert atmosphere.

The solid electrolyte glass ceramic of the present invention has high ionic conductivity, for example, 1 × 10 ⁻³ S / cm or more, more preferably 1.5 × 10 ⁻³ S / cm or more. By having such ionic conductivity, the all solid state battery using the solid electrolyte glass ceramic of the present invention can realize high output.

  Since the solid electrolyte glass ceramic of the present invention is difficult to hydrolyze and has high ionic conductivity, it is suitable as a constituent material of an all-solid battery such as a solid electrolyte layer.

The solid electrolyte glass and / or solid electrolyte glass ceramic of the present invention can be made into a positive electrode mixture by mixing with a positive electrode active material. Moreover, it can be set as a negative electrode compound material by mixing with a negative electrode active material.
The solid electrolyte glass and / or solid electrolyte glass ceramic of the present invention can also be used as a material for the solid electrolyte layer of an all-solid battery.

As the positive electrode active material that can be used in the positive electrode mixture of the present invention, a material that can insert and desorb lithium ions, and a material that is known as a positive electrode active material in the battery field can be used.
For example, V ₂ O ₅ , LiCoO ₂ , LiNiO ₂ , LiMnO ₂ , LiMn ₂ O ₄ , Li (Ni _a Co _b Mn _c ) O ₂ (where 0 <a <1, 0 <b <1, 0 < c <1, a + b + c = 1), LiNi _1-Y Co _{Y 2} O ₂ , LiCo _1-Y Mn _{Y 2} O ₂ , LiNi _1-Y Mn _{Y 2} O ₂ (where 0 ≦ Y <1), Li (Ni _{a Co b Mn c) O 4 (} 0 <a <2,0 <b <2,0 <c <2, a + b + c = 2), LiMn 2-Z Ni Z O 4, LiMn 2-Z Co Z O 4 ( wherein 0 <Z <2), LiCoPO ₄ , LiFePO ₄ , bismuth oxide (Bi ₂ O ₃ ), bismuth lead acid (Bi ₂ Pb ₂ O ₅ ), copper oxide (CuO), vanadium oxide (V ₆ O ₁₃ ) _{, Li x CoO 2, Li x} NiO 2, Li Mentioned _{Mn 2 O 4, Li x FePO} 4, Li x CoPO 4, Li x Mn 1/3 Ni 1/3 Co 1/3 O 2, oxides such as Li _x Mn _{1.5 Ni} 0.5 _{O 2} is It is done. Other positive electrode active materials include, for example, elemental sulfur (S), titanium sulfide (TiS ₂ ), molybdenum sulfide (MoS ₂ ), iron sulfide (FeS, FeS ₂ ), copper sulfide (CuS) in the sulfide system. And nickel sulfide (Ni ₃ S ₂ ), lithium sulfide (Li ₂ S), organic disulfide compounds, carbon sulfide compounds, sulfur, and the like can be used. Preferably, S and Li ₂ S having a high theoretical capacity can be used.

Organic disulfide compounds and carbon sulfide compounds are exemplified below.

In formulas (A) to (C), X is a substituent, n and m are each independently an integer of 1 to 2, and p and q are each independently an integer of 1 to 4.
In formula (D), Z is -S- or -NH-, respectively, and n is an integer of 2 to 300 repetitions.

As the negative electrode active material that can be used in the negative electrode mixture of the present invention, a material that can insert and desorb lithium ions, and a known negative electrode active material in the battery field can be used.
For example, carbon materials, specifically artificial graphite, graphite carbon fiber, resin-fired carbon, pyrolytic vapor-grown carbon, coke, mesocarbon microbeads (MCMB), furfuryl alcohol resin-fired carbon, polyacene, pitch-based carbon Examples thereof include fibers, vapor-grown carbon fibers, natural graphite, and non-graphitizable carbon. Or it may be a mixture thereof. Preferably, it is artificial graphite.

  Also, an alloy in combination with a metal itself such as metallic lithium, metallic indium, metallic aluminum, metallic silicon, or another element or compound can be used as the negative electrode material. Among these, silicon, tin, and lithium metal having a high theoretical capacity are preferable.

If necessary, a binder (binder), a conductive aid, and the like may be added to the positive electrode mixture, the negative electrode mixture, and the solid electrolyte layer of the present invention.
Examples of the binder include polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVdF), fluorine-containing resins such as fluorine rubber, thermoplastic resins such as polypropylene and polyethylene, ethylene-propylene-dienemer (EPDM), sulfonated EPDM, Natural butyl rubber (NBR) or the like can be used alone or as a mixture of two or more. In addition, an aqueous dispersion of cellulose or styrene butadiene rubber (SBR), which is an aqueous binder, can also be used.

The conductive auxiliary agent only needs to have conductivity. For example, the conductivity is preferably 1 × 10 ³ S / cm or more, more preferably 1 × 10 ⁵ S / cm or more.
Examples of the conductive assistant include substances selected from carbon materials, metal powders and metal compounds, and mixtures thereof.
Specific examples of conductive aids include carbon, nickel, copper, aluminum, indium, silver, cobalt, magnesium, lithium, chromium, gold, ruthenium, platinum, beryllium, iridium, molybdenum, niobium, osnium, rhodium, tungsten and zinc. A substance containing at least one element selected from the group consisting of: More preferably, it is a simple substance of carbon, carbon, nickel, copper, silver, cobalt, magnesium, lithium, ruthenium, gold, platinum, niobium, osnium or rhodium, a simple substance, a mixture or a compound having high conductivity.

Specific examples of the carbon material include carbon black such as ketjen black, acetylene black, denka black, thermal black and channel black, graphite, carbon fiber, activated carbon and the like. These can be used alone or in combination of two or more.
Among these, acetylene black, denka black, and ketjen black having high electron conductivity are preferable.

In addition to the solid electrolyte glass or solid electrolyte glass ceramic of the present invention, the positive electrode mixture, negative electrode mixture and solid electrolyte layer of the present invention may contain other electrolytes depending on the purpose of use.
Other electrolytes include polymer solid electrolytes, oxide solid electrolytes, and sulfide solid electrolytes.
The polymer-based solid electrolyte is not particularly limited. For example, as disclosed in JP 2010-262860 A, materials used as a polymer electrolyte such as a fluororesin, polyethylene oxide, polyacrylonitrile, polyacrylate, derivatives thereof, and copolymers thereof can be used.

  As a fluororesin, what contains vinylidene fluoride (VdF), hexafluoropropylene (HFP), tetrafluoroethylene (TFE), these derivatives, etc. as a structural unit is mentioned, for example. Specifically, a homopolymer such as polyvinylidene fluoride (PVdF), polyhexafluoropropylene (PHFP), polytetrafluoroethylene (PTFE), or a copolymer of VdF and HFP (hereinafter, this copolymer is referred to as “ P (VdF-HFP) ”may be used, and binary copolymers and ternary copolymers.

Examples of the oxide-based solid electrolyte include crystals having a perovskite structure such as LiN, LISICON, Thio-LISICON, La _0.55 Li _0.35 TiO ₃ , LiTi ₂ P ₃ O ₁₂ having a NASICON type structure, These crystallized electrolytes can be used.

In the all solid state battery of the present invention, at least one of the positive electrode layer, the electrolyte layer, and the negative electrode layer includes the solid electrolyte glass or the solid electrolyte glass ceramic of the present invention. Each layer can be manufactured by a known method.
As long as the above-described solid electrolyte glass or solid electrolyte glass ceramic of the present invention is used, there is no limitation on other configurations. For example, there are an all-solid battery including a positive electrode layer made of the positive electrode mixture described above, an all-solid battery including a negative electrode layer formed of a negative electrode mixture, and an all-solid battery including a solid electrolyte.

  In addition, when manufacturing a positive electrode layer, a negative electrode layer, or a solid electrolyte layer using the solid electrolyte glass described above, after forming a layer containing the solid electrolyte glass, differential scanning calorimetry (under a dry nitrogen atmosphere) of the solid electrolyte glass is performed. Heat treatment at a temperature between two exothermic peaks separated from each other in the range of 150 ° C. to 350 ° C. observed at a heating rate of 10 ° C./min, 20 to 600 ° C. The all solid state battery of the invention can also be manufactured.

In addition, it is preferable that a positive electrode layer contains a positive electrode active material, electrolyte, and a conductive support agent. Moreover, the binder may be included. In the positive electrode layer, the ratios of the positive electrode active material, the electrolyte, the conductive auxiliary agent and the like are not particularly limited, and known ratios can be used.
The thickness of the positive electrode layer is preferably 0.01 mm or more and 10 mm or less.
The positive electrode layer can be produced by a known method. For example, it can be produced by a coating method or an electrostatic method (electrostatic spray method, electrostatic screen method, etc.).

It is preferable that a negative electrode layer contains a negative electrode active material, an electrolyte, and a conductive support agent. Moreover, the binder may be included. The formation method and thickness are the same as in the case of the positive electrode.
The solid electrolyte of the solid electrolyte layer is preferably fused. Here, the fusion means that a part of the solid electrolyte particles is dissolved, and the dissolved part is integrated with other solid electrolyte particles.
The solid electrolyte layer may be a solid electrolyte plate. In addition, the case where part or all of the solid electrolyte particles are dissolved to form a plate-like body is included.
The thickness of the electrolyte layer is preferably 0.001 mm or more and 1 mm or less.

  The all solid state battery of the present invention preferably uses a current collector in addition to the positive electrode layer, the solid electrolyte layer, and the negative electrode layer. A known current collector can be used. For example, a layer coated with Au or the like that reacts with a sulfide-based solid electrolyte such as Au, Pt, Al, Ti, or Cu can be used.

  The all solid state battery of the present invention is a battery using an alkali metal electrolyte such as a lithium ion battery or a sodium ion battery, or a battery using a divalent cation electrolyte such as magnesium ion.

Hereinafter, the present invention will be described in more detail with reference to examples.
Production Example 1 [Production of lithium sulfide (Li ₂ S)]
Production and purification of lithium sulfide were performed in the same manner as in the examples of International Publication WO2005 / 040039A1. Specifically, it is as follows.
(1) Production of lithium sulfide A 10-liter autoclave equipped with a stirring blade was charged with 3326.4 g (33.6 mol) of N-methyl-2-pyrrolidone (NMP) and 287.4 g (12 mol) of lithium hydroxide at 300 rpm. The temperature was raised to 130 ° C. After the temperature rise, hydrogen sulfide was blown into the liquid at a supply rate of 3 liters / minute for 2 hours.
Subsequently, this reaction solution was heated in a nitrogen stream (200 cc / min) to dehydrosulfide a part of the reacted hydrogen sulfide. As the temperature increased, water produced as a by-product due to the reaction between hydrogen sulfide and lithium hydroxide started to evaporate, but this water was condensed by the condenser and extracted out of the system. While water was distilled out of the system, the temperature of the reaction solution rose, but when the temperature reached 180 ° C., the temperature increase was stopped and the temperature was kept constant. After the dehydrosulfurization reaction was completed (about 80 minutes), the reaction was completed to obtain lithium sulfide.

(2) Purification of lithium sulfide After decanting NMP in the 500 mL slurry reaction solution (NMP-lithium sulfide slurry) obtained in (1) above, 100 mL of dehydrated NMP was added and stirred at 105 ° C. for about 1 hour. . NMP was decanted at that temperature. Further, 100 mL of NMP was added, stirred at 105 ° C. for about 1 hour, NMP was decanted at that temperature, and the same operation was repeated a total of 4 times. After completion of the decantation, lithium sulfide was dried at 230 ° C. (temperature higher than the boiling point of NMP) under a nitrogen stream for 3 hours under normal pressure. The impurity content in the obtained lithium sulfide was measured.
Incidentally, lithium sulfite _(Li 2 _SO 3), the content of each sulfur oxide lithium sulfate _(Li 2 SO ₄₎ and lithium thiosulfate _{(Li 2 S 2 O 3)} , and N- methylamino acid lithium (LMAB) Was quantified by ion chromatography. As a result, the total content of sulfur oxides was 0.13% by mass, and LMAB was 0.07% by mass.

Example 1 [Raw material ratio: Li ₂ S / P ₂ S ₅ /LiBr=75/25/16.8): MM method]
(1) Synthesis of solid electrolyte glass 0.337 g (0.00717 mol) of lithium sulfide produced in Production Example 1, 0.532 g (0.00239 mol) of phosphorus pentasulfide (manufactured by Aldrich), lithium bromide (manufactured by Aldrich) ) 0.140 g (0.00161 mol) was mixed well in a glove box in an argon atmosphere. The mixed powder, 10 zirconia balls having a diameter of 10 mm, and a planetary ball mill (manufactured by Fritsch: Model No. P-7) were put in an alumina pot and completely sealed. Therefore, the inside of the pot is an argon atmosphere.
For the first few minutes, the planetary ball mill was rotated at a low speed (100 rpm) to sufficiently mix lithium sulfide and diphosphorus pentasulfide. Thereafter, the rotational speed of the planetary ball mill was gradually increased to 370 rpm. Mechanical milling was performed for 20 hours at a rotational speed of the planetary ball mill at 370 rpm.

In FIG.1 and FIG.2, the analysis result by differential thermogravimetry is shown.
Further, among the exothermic peaks observed in the range of 150 ° C. to 350 ° C., the position of each peak top (Tc1 and Tc2) when the low temperature side is the first peak and the high temperature side peak is the second peak, Table 1 shows the temperature width between peaks (ΔT).
The differential scanning calorimetry was carried out at 20 to 600 ° C. in a dry nitrogen atmosphere at a heating rate of 10 ° C./min. Using a differential thermal-thermogravimetric measuring apparatus (TGA / DSC1 manufactured by METTLER TOLEDO), the measurement was performed with about 20 mg of solid electrolyte glass.

(2) Synthesis of solid electrolyte glass ceramic The obtained solid electrolyte glass was heat-treated at a temperature between two exothermic peaks (230 ° C) for 2 hours in an argon atmosphere.
The results of differential thermal analysis after the heat treatment are shown in FIG.
As a result of the heat treatment, it can be seen that the peak on the low temperature side disappears and only the second peak on the high temperature side is present.
In differential thermal analysis measurement, the integrated intensity of the first peak before heat treatment is Hc1p, the integrated intensity of the second peak is Hc2p, the integrated intensity of the first peak after heat treatment is Hc1, and the integrated intensity of the second peak is Hc2. Table 1 shows the peak intensity ratio (Hc1 / Hc1p and Hc2 / Hc2p) before and after the heat treatment.
In the differential thermal analysis results, the integration of peak values was calculated by analysis software attached to the apparatus. Specifically, the differential thermal analysis result curve was normalized by weight, and integration was performed by specifying an integration range. As the base line, a range of 75-150 ° C. approximated by a straight line and extrapolated was used. However, a straight line was approximated in a range excluding the range, and a baseline was defined for those judged to be curved due to a crystallization peak or a glass transition point in a range of 75 to 150 ° C. The range of integration is within the range of ± 20 ° C from the peak top position of each peak, where the absolute value of (Heat flow value at each temperature-baseline value) is the smallest on the low temperature side from the peak top to the high temperature side from the peak top. Until the smallest. In the range, the integrated intensity was calculated by analysis software.
Peak positions Tc1 and Tc2, and peak integrated intensities Hc1, Hc2, Hc1p, and Hc2p were obtained.
Table 1 shows the ionic conductivity (σ) measured after the heat treatment.
In addition, the measuring method of ion conductivity is as follows.

・ Ionic conductivity (σ)
A powder sample of the solid electrolyte glass is formed into a shape having a cross section of 10 mmφ (cross section S = 0.785 cm ² ) and a height (L) of 0.1 to 0.3 cm. Then, it heat-processes and turns into glass ceramic.
Take electrode terminals from above and below the specimen. Measurement was performed by the AC impedance method (frequency range: 5 MHz to 0.5 Hz, amplitude: 10 mV), and a Cole-Cole plot was obtained. In the vicinity of the right end of the arc observed in the high-frequency region, the real part Z ′ (Ω) at the point where −Z ″ (Ω) is minimized is defined as the bulk resistance R (Ω) of the electrolyte. The conductivity σ (S / cm) was calculated.
R = ρ (L / S)
σ = 1 / ρ
The lead distance was measured as about 60 cm.

Comparative Example 1 [Raw material ratio: Li ₂ S / P ₂ S ₅ /LiBr=67/33/17.3): MM method]
The raw materials were changed to 0.264 g (0.0056 mol) of lithium sulfide, 0.616 g (0.00276 mol) of diphosphorus pentasulfide (Aldrich), and 0.127 g (0.00145 mol) of lithium bromide (Aldrich). A solid electrolyte glass and a solid electrolyte glass ceramic were produced and evaluated in the same manner as in Example 1 except that the heat treatment temperature for glass ceramicization was 270 ° C. The results are shown in Table 1.
The result of the differential thermal analysis of the solid electrolyte glass is shown in FIG.

Example 2 [Raw material ratio: Li ₂ S / P ₂ S ₅ /LiBr=77/23/17.3): MM method]
The raw materials were changed to 0.349 g (0.0076 mol) of lithium sulfide, 0.503 g (0.00227 mol) of diphosphorus pentasulfide (manufactured by Aldrich) and 0.148 g (0.00171 mol) of lithium bromide (manufactured by Aldrich). A solid electrolyte glass and a solid electrolyte glass ceramic were produced and evaluated in the same manner as in Example 1 except that the heat treatment temperature for glass ceramicization was 220 ° C. The results are shown in Table 1.
The result of the differential thermal analysis of the solid electrolyte glass is shown in FIG.

Example 3 [Raw material ratio: Li ₂ S / P ₂ S ₅ /LiBr=80/20/17.9): MM method]
The raw materials were changed to 0.384 g (0.0083 mol) of lithium sulfide, 0.460 g (0.00207 mol) of diphosphorus pentasulfide (Aldrich), and 0.162 g (0.00187 mol) of lithium bromide (Aldrich). A solid electrolyte glass and a solid electrolyte glass ceramic were produced and evaluated in the same manner as in Example 1 except that the heat treatment temperature for glass ceramicization was 220 ° C. The results are shown in Table 1.
The result of the differential thermal analysis of the solid electrolyte glass is shown in FIG.

Comparative Example 2 [Raw material ratio: Li ₂ S / P ₂ S ₅ /LiBr=83/16/18.7): MM method]
The raw materials were changed to 0.422 g (0.0091 mol) lithium sulfide, 0.405 g (0.00182 mol) diphosphorus pentasulfide (Aldrich), and 0.178 g (0.00205 mol) lithium bromide (Aldrich). A solid electrolyte glass and a solid electrolyte glass ceramic were produced and evaluated in the same manner as in Example 1 except that the heat treatment temperature for glass ceramicization was 180 ° C. The results are shown in Table 1.
The result of the differential thermal analysis of the solid electrolyte glass is shown in FIG.

Comparative Example 3 [Raw material ratio: Li ₂ S / P ₂ S ₅ /LiBr=86/14/19.0): MM method]
The raw materials were changed to 0.453 g (0.0098 mol) of lithium sulfide, 0.362 g (0.00163 mol) of diphosphorus pentasulfide (manufactured by Aldrich) and 0.191 g (0.00220 mol) of lithium bromide (manufactured by Aldrich). A solid electrolyte glass and a solid electrolyte glass ceramic were produced and evaluated in the same manner as in Example 1 except that the heat treatment temperature for glass ceramicization was 190 ° C. The results are shown in Table 1.
The result of the differential thermal analysis of the solid electrolyte glass is shown in FIG.

Example 4
[Raw material ratio: Li ₂ S / P ₂ S ₅ / PBr ₃ = 80/20/5): MM method]
The raw materials were changed to 0.397 g (0.00844 mol) of lithium sulfide, 0.467 g (0.00210 mol) of phosphorous pentasulfide (manufactured by Aldrich), and 0.147 g (0.00053 mol) of phosphorus tribromide to make glass ceramic. A solid electrolyte glass and a solid electrolyte glass ceramic were produced and evaluated in the same manner as in Example 1 except that the heat treatment temperature was 240 ° C. The results are shown in Table 1.
Compared to Example 1, the second peak shifted to the high temperature side, and ΔT widened.

Example 5 [Raw material ratio: Li ₂ S / P ₂ S ₅ /LiBr=75/25/16.8): MM method]
(1) Synthesis of solid electrolyte glass 0.337 g (0.00717 mol) of lithium sulfide produced in Production Example 1 and 0.532 g (0.00239 mol) of diphosphorus pentasulfide (manufactured by Aldrich) were mixed and the same as in Example 1. Then, it was mechanically milled with a ball mill to obtain a sulfide glass (precursor).
To the obtained precursor, 0.140 g (0.00161 mol) of lithium bromide (Aldrich) was added and mixed well. Furthermore, mechanical milling was performed under the same conditions as described above (rotation speed: 370 rpm, 20 hours) to obtain a solid electrolyte glass.
The results evaluated in the same manner as in Example 1 are shown in Table 1. In this solid electrolyte glass, the first peak temperature decreased, and ΔT became wider than that in Example 1.

(2) Synthesis of solid electrolyte glass ceramic The obtained solid electrolyte glass was heat-treated at a temperature between two exothermic peaks (220 ° C) for 2 hours in an argon atmosphere.
The solid electrolyte glass ceramic was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Reference Example 6 [Raw material ratio: Li ₂ S / P ₂ S ₅ /LiI=75/25/16.8): MM method]
The raw materials were changed to 0.316 g (0.0067 mol) of lithium sulfide, 0.494 g (0.00222 mol) of diphosphorus pentasulfide (manufactured by Aldrich) and 0.200 (0.00149 mol) of LiI, and the heat treatment temperature for glass ceramicization was changed. A solid electrolyte glass and a solid electrolyte glass ceramic were produced and evaluated in the same manner as in Example 5 except that the temperature was 210 ° C. The results are shown in Table 1.

Reference Example 7 [Raw material ratio: Li ₂ S / P ₂ S ₅ / PI ₃ = 80/20/5): MM method]
Example 4 except that the raw materials were changed to 0.369 g (0.0078 mol) of lithium sulfide, 0.434 g (0.00195 mol) of diphosphorus pentasulfide (Aldrich) and PI ₃ 0.417 (0.00050 mol). Similarly, solid electrolyte glass and solid electrolyte glass ceramic were produced and evaluated. The results are shown in Table 1.

Example 8
[Raw material ratio: Li ₂ S / P ₂ S ₅ /LiBr=75/25/16.8): MM method]
A solid electrolyte glass and a solid electrolyte glass ceramic were produced and evaluated in the same manner as in Example 1 except that the preparation into the mill pot was performed in dry air having a dew point of −40 ° C. or lower. The oxygen concentration at this time was about 20%. The results are shown in Table 1. Compared to Example 1, the first peak shifted to the low temperature side.

Example 9
[Raw material ratio: Li ₂ S / P ₂ S ₅ /LiBr=75/25/16.8): Slurry method]
(1) Synthesis of solid electrolyte glass The apparatus shown in FIG. 3 was used. The manufacturing apparatus 1 includes a bead mill 10 that reacts while pulverizing raw materials, and a reaction tank 20 that reacts the raw materials. The reaction tank 20 includes a container 22 and a stirring blade 24. The stirring blade 24 is driven by a motor (M).
The bead mill 10 is provided with a heater 30 through which hot water can be passed around the mill 10. The reaction tank 20 is in an oil bath 40. The oil bath 40 heats the raw material and solvent in the container 22 to a predetermined temperature. The reaction tank 20 is provided with a cooling pipe 26 that cools and vaporizes the evaporated solvent.
The bead mill 10 and the reaction tank 20 are connected by a first connecting pipe 50 and a second connecting pipe 52. The first connecting pipe 50 moves the raw material and the solvent in the bead mill 10 to the reaction tank 20, and the second connecting part 52 moves the raw material and the solvent in the reaction tank 20 into the bead mill 10. A pump 54 (for example, a diaphragm pump) is provided in the second connection pipe 52 in order to circulate the raw materials and the like through the connection pipes 50 and 52.
As the bead mill 10, Starmill Minizea (0.15 L) (bead mill) manufactured by Ashizawa Finetech Co., Ltd. was used, and 444 g of 0.5 mmφ zirconia balls were charged. As the reaction tank 20, a 1.5 L glass reactor with a stirrer was used. A 1.5 L glass reactor with a stirrer was used as a temperature holding tank.
In addition, all the equipment used remove | eliminated the water | moisture content beforehand with the dryer. The water content in dehydrated toluene was 8.4 ppm as measured by the Karl Fischer method.

Lithium sulfide of Preparation 1 33.7 g (64 _mol%), P 2 _{S 5} (Aldrich) 53.2 g (21 mol%), the LiBr (Aldrich) 14.1 g (15 mol%), dehydrated toluene ( Wako Pure Chemical Industries, Ltd.) 1248 ml (moisture content 8.4 ppm) was added to the temperature holding tank and mill. The raw material preparation and product recovery were performed in dry air with a dew point of -40 ° C or lower.

The content was circulated between the temperature holding tank and the mill at a flow rate of 480 mL / min by a pump, and the temperature holding tank was heated to 80 ° C.
The mill body was operated under conditions of a peripheral speed of 12 m / s by passing warm water by external circulation so that the liquid temperature could be maintained at 70 ° C.
The obtained slurry was filtered and air-dried and then dried with a tube heater at 160 ° C. for 2 hours to obtain a solid electrolyte glass as a powder. The recovery rate at this time was 95%, and no deposits were observed in the reactor. The evaluation results are shown in Table 1.

(2) Synthesis of solid electrolyte glass ceramic The obtained solid electrolyte glass was heat-treated at a temperature between two exothermic peaks (210 ° C) for 2 hours in an argon atmosphere.
The solid electrolyte glass ceramic was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 10
[Raw material ratio: Li ₂ S / P ₂ S ₅ /LiBr=74.4/25.6/17.3): MM method]
The raw materials were changed to 0.329 g (0.0070 mol) of lithium sulfide, 0.537 g (0.00241 mol) of diphosphorus pentasulfide (manufactured by Aldrich) and 0.144 (0.00164 mol) of lithium bromide. A solid electrolyte glass and a solid electrolyte glass ceramic were produced and evaluated in the same manner as in Example 1 except that the heat treatment temperature was 220 ° C. The results are shown in Table 1.

Example 11
[Raw material ratio: Li ₂ S / P ₂ S ₅ / LiBr / Li ₂ SO ₃ = 74.4 / 25.6 / 17.3 / 1.2): MM method]
Solid electrolyte glass and solid electrolyte glass ceramic were added in the same manner as in Example 1 except that 1 wt% Li ₂ SO ₃ (0.0101 g, 0.00011 mol) was added as a raw material, and the heat treatment temperature for glass ceramicization was 220 ° C. Manufactured and evaluated. The results are shown in Table 1. Li ₂ SO ₃ was previously vacuum dried.

Example 12
[Raw material ratio: Li ₂ S / P ₂ S ₅ / LiBr / Li ₂ SO ₃ = 74.4 / 25.6 / 17.3 / 2): MM method]
A solid electrolyte glass and a solid electrolyte glass ceramic were produced and evaluated in the same manner as in Example 11 except that ₂ wt% Li ₂ SO ₃ (0.020 g, 0.00021 mol) was further added as a raw material. The results are shown in Table 1.

Example 13
[Raw material ratio: Li ₂ S / P ₂ S ₅ / LiBr / Li ₂ SO ₃ = 74.4 / 25.6 / 17.3 / 5): MM method]
A solid electrolyte glass and a solid electrolyte glass ceramic were produced and evaluated in the same manner as in Example 11 except that 5 wt% Li ₂ SO ₃ (0.050 g, 0.00053 mol) was further added as a raw material. The results are shown in Table 1.

Comparative Example 4
A solid electrolyte glass ceramic was produced and evaluated in the same manner as in Example 1 except that the solid electrolyte glass obtained in Example 1 was heat-treated at 200 ° C. for 2 hours. The results are shown in Table 1.

Comparative Example 5
A solid electrolyte glass ceramic was produced and evaluated in the same manner as in Example 1 except that the solid electrolyte glass obtained in Example 1 was heat-treated at 300 ° C. for 2 hours. The results are shown in Table 1.

Example 14
A solid electrolyte glass ceramic was produced and evaluated in the same manner as in Example 1 except that the solid electrolyte glass obtained in Example 1 was heat-treated at 250 ° C. for 2 hours. The results are shown in Table 1.

Ｔｃ１：低温側の発熱ピークのピーク温度
Ｔｃ２：高温側の発熱ピークのピーク温度
ΔＴ：ピーク間温度（Ｔｃ２−Ｔｃ１）
Ｈｃ１：熱処理後の第一ピークの積分強度
Ｈｃ２：熱処理後の第二ピークの積分強度
Ｈｃ１ｐ：熱処理前の第一ピークの積分強度
Ｈｃ２ｐ：熱処理前の第二ピークの積分強度
σ：イオン伝導度

Tc1: Peak temperature of the exothermic peak on the low temperature side Tc2: Peak temperature of the exothermic peak on the high temperature side ΔT: Temperature between peaks (Tc2-Tc1)
Hc1: Integral intensity of the first peak after heat treatment Hc2: Integral intensity of the second peak after heat treatment Hc1p: Integral intensity of the first peak before heat treatment Hc2p: Integral intensity of the second peak before heat treatment σ: Ionic conductivity

The solid electrolyte glass and solid electrolyte ceramic of the present invention are suitable as a constituent material of an all-solid battery such as a positive electrode layer, a solid electrolyte layer, and a negative electrode.
The all solid state battery of the present invention can be used as a battery for a portable information terminal, a portable electronic device, a small electric power storage device for home use, a motorcycle using a motor as a power source, an electric vehicle, a hybrid electric vehicle and the like.

DESCRIPTION OF SYMBOLS 1 Manufacturing apparatus 10 Bead mill 20 Reaction tank 22 Container 24 Stirring blade 26 Cooling pipe 30 Heater 40 Oil bath 50 1st connection pipe 52 2nd connection pipe 54 Pump

Claims (15)

Lithium (Li) element;
Phosphorus (P) element, sulfur (S) element,
Bromine (Br) element ,
In differential scanning calorimetry (in dry nitrogen atmosphere, heating rate 10 ° C./min, 20 to 600 ° C.), it has two exothermic peaks separated from each other in the range of 150 ° C. to 350 ° C.,
Ri 0.99 ° C. der less temperature difference is 20 ° C. or more peak top position of the two exothermic peaks,
Solid electrolyte glass in which the molar ratio of Li, P, S, and Br satisfies the following formulas (α) and (β).
Li ₂ S: P ₂ S ₅ = 74.4: 25.6 to 80:20 (molar ratio) (α)
(Li ₂ S + P ₂ S ₅ ): (LiBr or PBr ₃ ) = 70: 30 to 96: 4 (molar ratio) (β)   2. The solid electrolyte glass according to claim 1, wherein a temperature difference between peak top positions of the two exothermic peaks is 30 ° C. or higher and 130 ° C. or lower. The manufacturing method of the solid electrolyte glass of Claim 1 or 2 which uses the following (A), (B) and (C) as a raw material.
(A) Lithium sulfide (B) M _'m S compounds represented by _{n (C) M "w X} y compound represented by (wherein, M' is P, M" indicates a Li or P , X represents one or more selected from I, Cl, Br and F, and represents a halogen element containing at least Br. W represents an integer of 1 to 2, and m, n and y represent 1 to 10. Indicates an integer.) The solid electrolyte glass of Claim 3 including the process of making the said raw material (A) and (B) react, and then adding the raw material (C) and making it react with the reaction material of the said raw material (A) and (B). Manufacturing method. Lithium element (Li), phosphorus (P) element, sulfur (S) element,
Bromine (Br) element ,
The molar ratio of Li, P, S and Br satisfies the following formulas (α) and (β),
A solid electrolyte glass ceramic having only one exothermic peak in a range of 150 ° C. to 350 ° C. in differential scanning calorimetry (in a dry nitrogen atmosphere, a rate of temperature increase of 10 ° C./min, 20 to 600 ° C.).
Li ₂ S: P ₂ S ₅ = 74.4: 25.6 to 80:20 (molar ratio) (α)
(Li ₂ S + P ₂ S ₅ ): (LiBr or PBr ₃ ) = 70: 30 to 96: 4 (molar ratio) (β) The solid electrolyte glass ceramic according to claim 5, wherein a peak top position of the one exothermic peak is 246 ° C. or higher and 312 ° C. or lower. 7. The solid electrolyte glass ceramic according to claim 5, wherein the ionic conductivity is 1 × 10 ⁻³ S / cm or more. The solid electrolyte glass according to claim 1 or 2, a heat treatment at a temperature between the two exothermic peaks, the method of manufacturing the solid body electrolyte glass ceramics. A method for producing a solid electrolyte glass ceramic according to any one of claims 5 to 7,
Using the solid electrolyte glass according to claim 1 or 2 as a raw material,
The method for producing a solid electrolyte glass ceramic , wherein the one exothermic peak is a peak on a high temperature side of two exothermic peaks of the solid electrolyte glass. A positive electrode mixture comprising at least one of the solid electrolyte glass according to claim 1 or 2 and the solid electrolyte glass ceramic according to any one of claims 5 to 7 and a positive electrode active material. A negative electrode mixture comprising at least one of the solid electrolyte glass according to claim 1 or 2 and the solid electrolyte glass ceramic according to any one of claims 5 to 7 and a negative electrode active material. An all solid state battery comprising a solid electrolyte layer containing at least one of the solid electrolyte glass according to claim 1 or 2 and the solid electrolyte glass ceramic according to any one of claims 5 to 7 . An all-solid battery comprising a positive electrode layer made of the positive electrode mixture according to claim 10 . An all-solid-state battery comprising a negative electrode layer made of the negative electrode mixture according to claim 11 . It is a manufacturing method of the all-solid-state battery in any one of Claims 12-14,
150 ° C. observed in differential scanning calorimetry (temperature increase rate 10 ° C./min, 20 to 600 ° C. in a dry nitrogen atmosphere) of the solid electrolyte glass contained in the solid electrolyte layer, the positive electrode mixture or the negative electrode mixture A method for producing an all-solid-state battery, wherein heat treatment is performed at a temperature between two exothermic peaks in the range of ˜350 ° C. between the exothermic peak temperatures .

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