JP6875050B2 - Solid electrolyte manufacturing equipment and manufacturing method - Google Patents

Description

The present invention relates to a solid electrolyte production facility and a production method.

With the rapid spread of information-related devices such as personal computers, video cameras, mobile phones, communication devices, etc. in recent years, the development of batteries used as their power sources has been emphasized. Lithium batteries are attracting attention as batteries used in these devices from the viewpoint of high energy density. Among them, since no flammable organic solvent is used in the batteries, safety devices are not required, and manufacturing costs and production are required. The development of solid electrolytes is underway because of its excellent properties and safety.

For example, Patent Document 1 states that a glass ceramics electrolyte having high ionic conductivity can be obtained by reacting lithium sulfide with phosphorus sulfide to produce sulfide glass and subjecting the sulfide glass to heat treatment. It has been reported (see, for example, Patent Document 1). However, higher ionic conductivity is required, and sulfide glass is produced by reacting lithium halide, lithium sulfide, and phosphorus sulfide, and the sulfide glass is heat-treated to have high ionic conductivity. It has been reported that a glass ceramic electrolyte can be obtained (see, for example, Patent Document 2).

The lithium halide contained in these raw material compositions is produced as a hydrate because it is produced by using the raw material of an aqueous solution in the synthesis process or by reacting in water (for example). See Patent Documents 3 to 6).

Japanese Unexamined Patent Publication No. 2005-228570 Japanese Unexamined Patent Publication No. 2013-201110 Japanese Unexamined Patent Publication No. 2013-103851 Japanese Unexamined Patent Publication No. 2013-256416 Japanese Unexamined Patent Publication No. 2014-65637 Japanese Unexamined Patent Publication No. 2014-65638

It is a schematic diagram of the reaction apparatus used in an Example.

By the way, if water is present in the raw material of the solid electrolyte, there is a problem that the ionic conductivity is remarkably lowered and an excellent solid electrolyte cannot be obtained. Since lithium halide produced by using water as a medium contains water as in the methods described in Patent Documents 3 to 6, lithium halide obtained by these methods should be used as a raw material. Then, a step of removing water is required. Specifically, the water is removed by firing at 300 to 440 ° C. in an inert gas atmosphere or in a vacuum (Patent Document 3), azeotropically drying with an organic solvent (Patent Document 4), and under reduced pressure. It is carried out by a method such as heating (Patent Documents 5 and 6).

However, it is not easy to remove these waters, and as described above, various measures are required (Patent Documents 3 to 6). For example, if the drying process is performed under reduced pressure and by heating, the manufacturing process becomes complicated and large, which requires labor and cost. As described above, the solid electrolyte made of lithium halogenated as a raw material has the advantages of high ionic conductivity and excellent battery performance, but requires a large amount of energy for removing water, and the manufacturing process is complicated and large. , The cost is high, and as a result, the cost is high.

The present invention has been made in view of such a situation, and an object of the present invention is to provide a solid electrolyte production facility and a production method capable of simplifying the production process and further safely and stably producing the solid electrolyte. And.

As a result of diligent studies to solve the above problems, the present inventor has found that the problems can be solved by the following inventions.

[1] A reactor for producing a solid electrolyte by reacting raw materials containing a lithium element, a sulfur element, a phosphorus element, and a halogen element.
A halogen supply means for supplying at least a substance represented by the following general formula (1) as a raw material containing the halogen element, and
Solid electrolyte manufacturing equipment with.
X ₂ ... (1)
(In the general formula (1), X is a halogen element.)
[2] The equipment for producing a solid electrolyte according to the above [1], wherein the halogen supply means includes a storage tank and a supply unit for the substance.
[3] The equipment for producing a solid electrolyte according to the above [2], wherein the supply unit of the substance has a function of adjusting the supply rate.
[4] The reaction apparatus includes a reaction tank and a crusher, and the halogen supply means is connected to at least one of the reaction tank, the crusher, and a means for connecting the reaction tank and the crusher. The equipment for producing a solid electrolyte according to any one of the above [1] to [3].
[5] Continuously adding a substance represented by the following general formula (1) to a raw material containing at least lithium element, sulfur element and phosphorus element.
Reacting the raw material with the substance,
A method for producing a solid electrolyte including.
X ₂ ... (1)
(In the general formula (1), X is a halogen element.)
[6] The method for producing a solid electrolyte according to the above [5], wherein the substance is added while reacting the raw material with the substance.

According to the present invention, it is possible to provide a production facility and a production method for a solid electrolyte, which can simplify the production process and further safely and stably produce a solid electrolyte.

Hereinafter, embodiments of the present invention (hereinafter, may be referred to as “the present embodiment”) will be described. In addition, in this specification, the numerical values relating to "greater than or equal to", "less than or equal to", "to", etc. relating to the description of the numerical range are numerical values that can be arbitrarily combined.

[Solid electrolyte manufacturing equipment]
The solid electrolyte manufacturing equipment of the present embodiment includes a reactor for producing a solid electrolyte by reacting raw materials containing a lithium element, a sulfur element, a phosphorus element and a halogen element, and at least the following general formula as a raw material containing the halogen element. It has a halogen supply means for supplying the substance represented by (1).
X ₂ ... (1)
(In the general formula (1), X is a halogen element.)

(material)
The raw material used in the present embodiment is a raw material containing a lithium element, a sulfur element, a phosphorus element and a halogen element, and as a raw material containing a halogen element, at least a substance represented by the following general formula (1) (hereinafter, "substance X"). _It may be referred to as "2").
X ₂ ... (1)
(In the general formula (1), X is a halogen element.)

Lithium halide is not easy to remove water in the manufacturing process, requires a large amount of energy to remove water, and the manufacturing process becomes complicated and large. In the present embodiment, _{by using the substance X 2} as a raw material, the halogen element can be supplied without using lithium halide or while reducing the amount used thereof. Further, by using a raw material containing a halogen element as a raw material, excellent battery performance with higher ionic conductivity can be obtained.
Examples of the substance X ₂ include fluorine (F ₂ ), chlorine (Cl ₂ ), bromine (Br ₂ ), iodine (I ₂ ), and chlorine (Cl) from the viewpoint of obtaining a solid electrolyte having high ionic conductivity. ₂ ), bromine (Br ₂ ) and iodine (I ₂ ) are preferable, and bromine (Br ₂ ) and iodine (I ₂ ) are more preferable. These substances X ₂ can be used alone or in combination of two or more.
The substance X ₂ preferably contains a small amount of water as an impurity.

Further, as raw materials other than the above substance X ₂ (hereinafter, raw materials exemplified as other raw materials may be referred to as "other raw materials other than _{substance X 2" and "other raw materials"), lithium.} Examples of the raw material containing the raw material _{preferably include lithium compounds such as lithium sulfide (Li 2} S), lithium oxide (Li ₂ O), lithium carbonate (Li ₂ CO ₃ ), and a single lithium metal, which are used alone. Or, a plurality of types can be used in combination. Examples of the lithium compound, the ion conductivity is higher, from the viewpoint of obtaining excellent battery performance, lithium sulfide (Li 2 _S) is particularly preferred. Although lithium sulfide (Li 2 _S) is a raw material containing a lithium element and sulfur element, in this embodiment, thus it may be a raw material containing a lithium element and sulfur element and a lithium metal alone The raw material may be composed of only the lithium element as in the above, or the above-mentioned lithium oxide (Li ₂ O) and lithium carbonate (Li ₂ CO ₃ ) containing the lithium element and elements other than the sulfur element and the phosphorus element. It may be a raw material such as.

Examples of the raw material containing a phosphorus element include phosphorus sulfide such as diphosphorus trisulfide (P ₂ S ₃ ) and diphosphorus pentasulfide (P ₂ S ₅ ), silicon sulfide (SiS ₂ ), germanium sulfide (GeS ₂ ), and the like. Boron sulfide (B ₂ S ₃ ), gallium sulfide (Ga ₂ S ₃ ), tin sulfide (SnS or SnS ₂ ), aluminum sulfide (Al ₂ S ₃ ), zinc sulfide (Zn _{S), sodium phosphate (Na 3} PO ₄₎ ) And the like, phosphorus alone and the like are preferably mentioned, and these can be used alone or in combination of two or more. As the phosphorus compound, the ion conductivity is higher, from the viewpoint of obtaining excellent battery performance, preferably phosphorus sulfide, diphosphorus pentasulfide (P 2 _{S 5)} is more preferable. Phosphorus pentasulfide (P 2 _{S 5)} phosphorus compounds such as phosphorus alone is industrially produced, and the like sold, can be used without particular limitation.

As the raw material containing a sulfur element, among the above-mentioned raw materials containing a lithium element and a raw material containing a phosphorus element, those containing a sulfur element are preferably mentioned. Further, as the raw material containing a sulfur element, _{alkali metals sulfides such as sodium sulfide (Na 2} S), potassium sulfide (K ₂ S), rubidium sulfide (Rb ₂ S) and cesium sulfide (Cs ₂ S) are also preferably mentioned. Be done. These alkali metal sulfides, by molecular weight using a smaller alkali metal, the ion conductivity of the resulting solid electrolyte is considered that there is a tendency of improvement, sodium sulfide (Na 2 _S) is more preferable. Further, as the alkali metal sulfide, also exemplified lithium sulfide (Li 2 _S) as a raw material containing the lithium, the molecular weight from the viewpoint of improving the ion conductivity is considered that it is preferable to use a smaller alkali metal, lithium sulfide _(Li 2 S) is preferred of course.

Further, in the present embodiment, in addition to the above raw materials, for example, the following raw materials can be used as the raw materials containing the lithium element, the sulfur element, the phosphorus element and the halogen element.
Silicon sulfide (SiS ₂ ), germanium sulfide (GeS ₂ ), boron sulfide (B ₂ S ₃ ), gallium sulfide (Ga ₂ S ₃ ), tin sulfide (SnS or SnS ₂ ), aluminum sulfide (Al ₂ S ₃ ), A sulfur element can be supplied by using a metal sulfide such as zinc sulfide (ZnS).

Various phosphorus pentafluoride _(PF 3, PF 5), various phosphorus trichloride _{(PCl 3, PCl 5, P} 2 Cl 4), phosphorus oxychloride (POCl _3), various kinds of phosphorus tribromide _(PBr 3, PBr 5), oxybromide phosphorus (POBr _3), with a phosphorus halide such as various iodide phosphorus _{(PI 3, P 2 I 4} ), can be supplied to the phosphorus element and a halogen element at the same time. Also, thiophosphoryl fluoride (PSF ₃ ), thiophosphoryl chloride (PSCl ₃ ), thiophosphoryl bromide (PSBr ₃ ), thiophosphoryl iodide (PSI ₃ ), thiophosphoryl dichloride (PSCl ₂ S), di using halogenated thiophosphoryl such bromide fluoride thiophosphoryl (pSBr 2 _F), it can be supplied to the phosphorus element and a sulfur element and a halogen element at the same time.

Sodium halides such as sodium iodide (NaI), sodium fluoride (NaF), sodium chloride (NaCl), sodium bromide (NaBr), aluminum halide, silicon halide, germanium halogenated, arsenic halide, halogenated Halogen elements can be supplied using metal halides such as selenium, tin halide, antimony halide, tellurium halide, and bismuth halide.

Further, for example, lithium halide such as lithium fluoride (LiF), lithium chloride (LiCl), lithium bromide (LiBr), lithium iodide (LiI) is used as long as the effect of the present embodiment is not impaired. Alternatively, a lithium element and a halogen element may be supplied.

In the present embodiment, among the above raw _{materials, as the raw material used together with the substance X 2} , it is preferable to use a lithium compound, an alkali metal sulfide, and a phosphorus compound, and the substance X ₂ and lithium sulfide (LiS) and phosphorus sulfide are used. It is more preferable to use lithium sulfide (LiS), diphosphorus pentasulfide (P ₂ S ₅ ), bromine (Br ₂ ) and / or iodine (I ₂ ).

The ratio of each of the above raw materials to the total raw materials is not particularly limited. For example, when lithium sulfide (Li ₂ S) and diphosphorus pentasulfide (P ₂ S ₅ ) are used as raw materials, the molar amount of the substance X _{2 is used.} to the total number of moles of lithium sulfide, except the number of the same number of moles of lithium sulfide _{(Li 2 S) (Li 2} S) and phosphorus pentasulfide _(P 2 _{S 5),} the moles of the number of moles of substance _{X 2} moles ratio of lithium sulfide excluding lithium sulfide _{(Li 2 S) (Li 2} S) , the ion conductivity higher, from the viewpoint of obtaining excellent battery performance, preferably 60 mol% or more, more It is preferably 65 mol% or more, further preferably 68 mol% or more, still more preferably 72 mol% or more, particularly preferably 73 mol% or more, and the upper limit is preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 82 mol%. Below, it is even more preferably 78 mol% or less, and particularly preferably 77 mol% or less.

In the case of using the a substance X ₂ alkali sulfide metal and phosphorus compounds such as lithium sulfide (Li 2 _S) as a starting material, the alkali metal sulfide, phosphorus compound, and the content of substance X ₂ to the total amount of material X ₂ is From the viewpoint of obtaining higher ionic conductivity and excellent battery performance, it is preferably 1 mol% or more, more preferably 2 mol% or more, further preferably 3 mol% or more, and the upper limit is preferably 50 mol% or less, more preferably. Is 40 mol% or less, more preferably 25 mol% or less, still more preferably 15 mol% or less.

When using the lithium sulfide as the starting material (Li 2 _S) and sodium sulfide metal and a phosphorus compound and a substance X _2, such as a lithium halide, the content of a substance X ₂ against the total amount thereof (αmol%), and halogen The lithium sulfide content (βmol%) preferably satisfies the following formula (1), more preferably the following formula (2), further preferably the following formula (3), and the following formula (4). ) Is even more preferable.
2 ≦ 2α ＋ β ≦ 100… Formula (1)
4 ≤ 2α + β ≤ 80 ... Formula (2)
6 ≤ 2α + β ≤ 50 ... Formula (3)
6 ≤ 2α + β ≤ 30 ... Formula (4)

When the raw material contains two types of halogen elements, the number of moles in the raw material of one halogen element is HM _1, and the number of moles in the raw material of the other halogen element is HM. _{If it is 2} , _{the ratio of HM 1} to the total of _{HM 1} and HM ₂ is preferably 1 mol% or more, more preferably 10 mol% or more, further preferably 20 mol% or more, still more preferably 30 mol% or more, and the upper limit. It is preferably 99 mol% or less, more preferably 90 mol% or less, still more preferably 80 mol% or less, still more preferably 70 mol% or less.

When the raw material contains bromine element and iodine element as halogen elements, the number of moles in the raw material of bromine element is BM _1, and the number of moles in the raw material of iodine element is IM _1. BM ₁ : I Is preferably 1 to 99: 99 to 1, more preferably 15:85 to 90:10, even more preferably 20:80 to 80:20, even more preferably 30:70 to 75:25, and particularly preferably 35. : 65-75: 25.

(Reactor)
The reactor, with the substance X _2, is not particularly limited as long as device capable of reacting with other materials other than materials X _2, for example, mixing the reaction of these raw materials, stirring, milling or these It is preferable that the device can be performed by a combined process.

The mixing method is not particularly limited, and for example, the raw material and, if necessary, a solvent and the like may be added to the raw material or an apparatus capable of mixing the raw material and the solvent for mixing. Here, the solvent is used as needed, and the details will be described later. As an apparatus capable of mixing the raw material or the raw material and the solvent, for example, a medium-type crusher can be used.
The medium-type crusher is roughly classified into a container-driven crusher and a medium-stirring crusher. Examples of the container-driven crusher include a stirring tank, a crushing tank, or a ball mill and a bead mill combining these (for example, those having the configuration shown in FIG. 1 described later). The medium stirring type crusher includes an impact type crushing machine such as a cutter mill, a hammer mill, and a pin mill; a tower type crushing machine such as a tower mill; a stirring tank type crushing machine such as an attritor, an aquamizer, and a sand grinder; Distribution tank type crushers such as pearl mills; distribution tube type crushers; general type crushers such as coball mills; continuous dynamic type crushers; various crushers such as uniaxial or multiaxial kneaders.

These crushers can be appropriately selected according to a desired scale and the like, and if the scale is relatively small, a container-driven crusher such as a ball mill or a bead mill can be used, and a relatively large scale. Alternatively, in the case of mass production, another type of crusher may be used.
When these crushers are used, the raw materials, the solvent, etc., and the crushing media may be charged, and the apparatus may be started to mix, stir, and crush. Here, the pulverized media is charged with the raw materials, the solvent, and the like, but the order of charging is not limited.

For example, an apparatus such as a ball mill or a bead mill will be described as an example. In these mills, the particle size of media such as balls and beads (balls are usually about φ2 to 20 mm, beads are about φ0.02 to 2 mm), materials (for example, φ0.02 to 2 mm) , Stainless steel, chrome steel, metals such as tungsten carbide; ceramics such as zirconia and silicon nitride; minerals such as menow), rotor rotation speed, time, etc., mixed, stirred, crushed, and combined. The treatment can be performed, and the particle size and the like of the obtained solid electrolyte can be adjusted.

In the present embodiment, these conditions are not particularly limited, but for example, a ball mill, particularly a planetary ball mill, a ceramic ball, especially a zirconia ball having a particle size of φ1 to 10 mm is used, and the rotor rotation speed is 300. It is preferable that the scale and performance are such that stirring and pulverization can be performed at ~ 1000 rpm for 0.5 to 100 hours.
The temperature at the time of mixing, stirring and pulverizing is not particularly limited, but it is preferable that the temperature can be, for example, about 20 to 80 ° C.

(Halogen supply means)
The solid electrolyte production facility of the present embodiment has a halogen supply means capable of supplying _{the substance X 2.} The form of the halogen supply means is not particularly limited, but for example, it is preferable to include a storage unit and a supply unit _{for the substance X 2.}
As the storage unit for the substance X ₂ , for example, a tank-shaped container having an inlet and an outlet for the _{substance X 2 can be used.} Although the substance X ₂ can be used as it is, it is preferably diluted and used because it is highly corrosive, that is, it is preferably dissolved in a solvent and used, and the storage portion preferably has a solvent supply port. .. Further, from the viewpoint of corrosion prevention, _{the storage portion of the substance X 2} may have a supply port for an inert gas such as nitrogen gas.

As the material of the storage part, a material having high halogen corrosion resistance, for example, a stainless steel having a high content of niobium, chromium, molybdenum, titanium, etc., or a material in which the inside of ordinary carbon steel is lined with resin, glass, etc. Is preferably used.

Supply of material X _2, for example a material X ₂ reservoirs may be constituted by a pipe for supplying the reaction vessel or the like. From the viewpoint of more efficiently promote the reaction of the other ingredients and materials X ₂ other than the above materials X _2, material X ₂ is preferably to supply while adjusting the flow rate, supply of material X ₂ is , It is preferable to have a flow rate adjusting function capable of adjusting the supply rate of the substance X _2. Further, by adjusting the flow rate of the material X _2, it is possible to suppress an abrupt rise in temperature due to the progress of local reactions with other ingredients and materials X ₂ other than material X _2, safety It becomes possible to stably produce an amorphous solid electrolyte.
As the flow rate adjusting function of the substance X ₂ , for example, a flow rate adjusting valve, a diaphragm type metering pump generally used as a chemical pump, a plunger type metering pump, an electromagnetic metering pump or the like, or the like with a flow rate adjustable pump may be used. The size and type of these flow rate adjusting functions may be appropriately selected according to the form (solid, liquid, gas) _{of the substance X 2 and the supply amount.}
The supply of the material X ₂ is the relationship between the feed point to the reactor the feed section and the storage section, if necessary, may have a pump for pumping the material X _2.

As the material of the supply unit, those exemplified as the material of the storage unit can be preferably used.

In the solid electrolyte manufacturing equipment of the present embodiment, the halogen supply means may be one or two or more in consideration of maintenance and the like. Further, for example, when two or more kinds of substances X ₂ are used, one halogen supply means may be used in common, or different substances X ₂ may be separately provided. In this case, a separately only reservoir for different material X _2, the supply section may also be combined with one.

The connection point of the supply unit of the halogen supply means to the reaction device, that _{is, the supply point of the substance X 2} is not particularly limited, but for example, when a stirring tank, a crushing tank, or a reaction device combining these is used, stirring is performed. It may be connected to any of the means for connecting the tank, the crushing tank, the piping connecting them, etc., but from the viewpoint of preventing deterioration of the device due to corrosion, it may be connected to the stirring tank and the crushing tank. Preferably, _{from the viewpoint of efficient reaction with other raw materials other than the substance X 2} , it is preferable to connect them so that they can be supplied into other raw materials and a solvent that are stirred in the stirring tank. Further, the number of connecting points may be one or two or more.

As the reaction apparatus and the halogen supply means used in the present embodiment, one of the typical embodiments thereof will be described with reference to FIG. The reaction apparatus shown in FIG. 1 includes a crushing tank (bead mill) 10 and a reaction tank 20 for reacting raw materials by mixing, stirring, pulverizing, or a treatment combining these. The reaction tank 20 includes a container 22 and a stirring blade 24, and the stirring blade 24 is driven by a motor (M).
The crushing tank (bead mill) 10 is provided with a heater 30 through which hot water (HW) can pass around the mill 10, and the hot water (HW) supplies heat by the heater 30 from the outlet of the heater 30. The discharged hot water (RHW) is heated and then circulated externally to the heater 30 as hot water (HW). The reaction tank 20 is contained in the oil bath 40. The oil bath 40 heats the raw material and the solvent in the container 22 to a predetermined temperature. The reaction tank 20 is provided with a cooling pipe 26 that cools and liquefies the vaporized solvent, and the cooling water (CW) cools the solvent in the cooling pipe 26 and is discharged from the outlet of the cooling pipe 26 (cooling water (CW)). After cooling the RCW), it is externally circulated as cooling water (CW) in the cooling pipe 26.
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 crushing tank (bead mill) 10 to the reaction tank 20, and the second connecting portion 52 moves the raw material and the solvent in the reaction tank 20 to the crushing tank (bead mill) 10. Move in. A pump 54 (for example, a diaphragm pump) is provided in the second connecting pipe 52 in order to circulate the raw materials and the like through the connecting pipes 50 and 52. Further, a thermometer (Th) is provided at the discharge of the reaction tank 20 and the pump 54 so that the temperature can be constantly controlled.

Further, the halogen supply means shown in FIG. 1 is provided with a storage tank as a storage unit 60 for the _{substance X 2 , and the storage tank has an inlet for the substance X 2 at} the top and a discharge port at the bottom. In addition, a pipe for supplying a solvent, an inert gas, etc. is connected. _{A supply unit 61 for the substance X 2} having a pipe and a flow rate control valve is provided at the discharge port at the bottom of the storage tank of the storage unit 60, and the supply unit 61 is connected to the reaction tank 20. The tip of the supply unit, as efficient reaction with other ingredients and materials X ₂ other than material X ₂ is accelerated, also material X ₂ is not in contact as much as possible directly with the inner wall of the reaction vessel 20 _{As described above, the substance X 2} is provided so as to reach the layer formed by stirring the raw materials, the solvent and the like in the reaction vessel 20, and the substance X 2 is supplied to the layer formed by the raw materials, the solvent and the like.
In FIG. 1, the connection destination of the supply unit 61 is in the reaction tank 20, but the connection destination is, for example, a pipe from the reaction tank 20 to the pump 54 and a pipe from the pump 54 to the crushing tank (bead mill) 10. As described above, the crushing tank (bead mill) 10 and the piping from the crushing tank (bead mill) 10 to the reaction tank 20 may be used. Further, as the connection destination of the supply unit 61, from the viewpoint of protecting the equipment of the pump 54, the reaction tank 20, the piping from the pump 54 to the crushing tank (bead mill) 10, the crushing tank (bead mill) 10, and the crushing tank (bead mill) 10 The piping from the reaction tank 20 to the reaction tank 20 is preferable, and from the viewpoint of protecting the equipment of the crushing tank (bead mill) 10 and the pump 54, the piping from the reaction tank 20, the pump 54 to the crushing tank (bead mill) 10, and the crushing tank (bead mill) 10 The piping to the reaction tank 20 is more preferable, and above all, as shown in FIG. 1, the reaction tank 20 is preferable.

(Device for solid-liquid separation)
The solid electrolyte manufacturing equipment of the present embodiment may include, for example, a solid-liquid separation device in addition to the above-mentioned reaction device and halogen supply means. When a solvent is used in the reaction of the raw materials, the solid electrolyte obtained by the reactor becomes a liquid accompanied by the solvent (hereinafter, may be referred to as "solid electrolyte-containing liquid"), so that the solvent is removed from the solid electrolyte-containing liquid. It is preferable to do so. When it is necessary to remove the solvent, a drying device that normally performs the drying process is provided, but by providing a device for solid-liquid separation and removing the solvent to some extent in advance, it is possible to reduce the load in the drying process. ..

The solid electrolyte-containing liquid is mainly a solid containing a solid electrolyte, an unreacted raw material (for example, a solid raw material such as lithium sulfide and diphosphorus pentasulfide), and mainly a solvent and an unreacted raw material (for example, substance X _2). Etc.), a liquid containing reaction by-products and the like. Further, the halogen as the reaction by-products contained in the liquid, when using a material X ₂ as a starting material, contained sulfur and the sulfur and the raw material produced by reaction with other ingredients and materials X ₂ other than material X ₂ Sulfur-containing compounds such as compounds containing at least sulfur elements, which are produced by the reaction of elements and solvents, and organic halogens containing at least halogen elements contained in the raw materials, which are produced by the reaction of halogen elements and solvents contained in the raw materials. Examples include compounds. By using the device for solid-liquid separation, the above solid and liquid can be separated.

Examples of the device for solid-liquid separation include a centrifuge, a vacuum filter, a decantable tank, and the like, and a decantable tank is more preferable from the viewpoint of more easily removing the solvent.

(Drying equipment)
The solid electrolyte production facility of the present embodiment may have a drying treatment apparatus. When a solvent is used in the reaction of the raw materials, it is preferable to remove the solvent because the solid electrolyte-containing liquid obtained by the reactor contains the solvent. The drying treatment apparatus dries a slurry containing a solid such as a solid electrolyte-containing liquid obtained by the reaction apparatus and a solid electrolyte obtained from the solid-liquid separating apparatus when having the solid-liquid separating apparatus, and dries the solid electrolyte. It is a facility to obtain the products of.
As the drying treatment device for the slurry containing the solid electrolyte, an appropriate method may be selected according to the treatment amount, and if the treatment amount is relatively small, for example, a heater such as a hot plate can be mentioned, and 50 to 90 The solvent can be removed by heating at ° C. Further, if the processing amount is relatively large, a method of drying using a drying device such as various industrial dryers can be mentioned.

Further, if the amount of treatment is relatively large, for example, a drying device capable of heating at about 50 to 90 ° C. and drying while stirring under a reduced pressure atmosphere of about 1 to 80 kPa can be used. By using such a drying device, the solid can be dried more efficiently, and the solvent can be easily recovered. As such a drying device, for example, a commercially available Henschel mixer or FM mixer can be used.

The solvent (gas) removed by the drying treatment apparatus may include fine particle solids such as a solid electrolyte and an unreacted raw material (for example, a solid raw material such as lithium sulfide and diphosphorus pentasulfide). In the present embodiment, the solvent (gas) containing the fine particle solids can be used as desired by removing the fine particle solids by a fine particle removing means such as a bag filter and condensing them into a liquid. It can be reused. Unlike the liquid obtained from the solid-liquid separation device, the solvent removed by the drying treatment device does not contain reaction by-products such as sulfur-containing compounds and organic halogen compounds, and these reaction by-products are removed. It is advantageous in that it can be reused as it is without being used.
Therefore, the solid electrolyte production facility of the present embodiment can have a means for supplying the solvent removed by the drying treatment device to the reaction device. The means for supplying the solvent removed by the drying treatment device to the reaction device may be shared with the means for supplying the reaction device, which may be provided in association with the liquid treatment device described later. Further, instead of the means for supplying the solvent removed by the drying treatment device to the reaction device, the solvent can be reused by having a means for supplying the solvent removed by the drying treatment device to the liquid processing device. May be good.

(Liquid processing device)
The solid electrolyte manufacturing equipment of the present embodiment may have a liquid processing apparatus for processing the liquid obtained from the solid-liquid separating apparatus. The liquid obtained from the solid-liquid separation device preferably provided when a solvent is used may contain a sulfur-containing compound such as sulfur and a reaction by-product such as an organic halogen compound in addition to the solvent. When these reaction by-products are contained in a solid electrolyte, for example, the ionic conductivity may be lowered and the excellent battery performance may be lowered, and they may not be preferable in other applications from the viewpoint of safety and the like. is there. Meanwhile, the solvent is, for example reaction with other ingredients and materials X ₂ other than material X _2, also because it can be used in other applications, reusing the solvent, emissions of waste from the manufacturing facility From the viewpoint of producing a solid electrolyte at a lower cost by reducing the supply amount of the solvent newly supplied to the reaction of the raw material, and further from the viewpoint of safety, it is preferable.
The solid electrolyte production facility of the present embodiment has a liquid processing device, which processes the liquid obtained from the device for solid-liquid separation, and is a reaction subordinate of the above-mentioned sulfur-containing compound such as sulfur and organic halogen compound. By removing the product, the treated liquid can be effectively reused as a solvent.

Examples of the method for removing the sulfur-containing compound such as sulfur from the liquid include oxide-based hydrodesulfurization agents such as iron oxide and zinc oxide, Y-type zeolite ion-exchanged with copper (Cu) and cerium (Ce), and silver. Liquid phase adsorption desulfurization method using a zeolite-based desulfurization agent such as β-zeolite ion-exchanged with (Ag); nickel (Ni), cobalt (Co), molybdenum (Mo), etc. on a carrier such as alumina, silica-alumina, etc. A hydrodesulfurization method using a hydrodesulfurization catalyst supporting the above metal; a distillation method using a flash drum, a distillation tower, or the like; and the like are preferably mentioned. From the viewpoint of removing sulfur-containing compounds more easily, a distillation method using a flash drum, a distillation column, or the like is more preferable. Further, when the liquid after solid-liquid separation contains an organic halogen compound, it is preferable to adopt the distillation method from the viewpoint that the organic halogen compound can be removed at the same time.

Regarding the distillation method, when one kind of solvent is used in the reaction, or when two or more kinds of solvents are used and it is not necessary to separate each solvent, a sulfur-containing compound or an organic halogen compound can be more easily used. From the viewpoint of removal, a distillation method using a flash drum is more preferable. Further, when two or more kinds of solvents are used in the reaction and it is necessary to separate each solvent, a distillation method using a distillation column may be adopted.

When a distillation method is adopted as a method for removing sulfur-containing compounds and organic halogen compounds, a flash drum and a distillation column that can withstand a normal pressure or a reduced pressure atmosphere (particularly vacuum) at 100 to 200 ° C. are adopted. It is preferable to do so.

Along with the liquid processing apparatus, there may be further means for supplying the solvent to the reactor in order to reuse the solvent obtained in the processing apparatus as a solvent in the reaction of the raw materials. Examples of the means for supplying the reaction device include those having a pipe from the liquid processing device to the reaction device and, if necessary, a pump for pumping the liquid.

(Solid electrolyte heating device)
The solid electrolyte manufacturing equipment of the present embodiment may have a solid electrolyte heating device that heats the solid electrolyte obtained by the drying treatment by the drying treatment device. The solid electrolyte obtained by the drying treatment by the above-mentioned drying treatment apparatus is an amorphous solid electrolyte described later, and by heating this with a heating apparatus, it can be obtained as a crystalline solid electrolyte described later.
The heating device is not particularly limited, but for example, a hot plate, a vacuum heating device, an argon gas atmosphere furnace, a firing furnace, and industrially, a horizontal dryer having a heating means and a feeding mechanism, a horizontal type. A vibration flow dryer or the like can also be used.

[Manufacturing method of solid electrolyte]
In the method for producing a solid electrolyte of the present embodiment, a substance represented by the following general formula (1) is continuously added to a raw material containing at least a lithium element, a sulfur element and a phosphorus element, and the raw material and the substance are combined. It involves reacting.
X ₂ ... (1)
(In the general formula (1), X is a halogen element.)

As raw materials containing at least lithium element, sulfur element and phosphorus element, raw materials containing lithium element and raw materials containing sulfur element exemplified as raw materials other than _{substance X 2 in the description of the solid electrolyte production equipment of the present embodiment.} , Raw materials containing phosphorus element, and in addition to these raw materials, those exemplified as raw materials containing lithium element, sulfur element, phosphorus element and halogen element can be mentioned. The conditions such as the blending ratio of these raw materials may be appropriately selected from the conditions described in the description of the solid electrolyte production equipment of the present embodiment, and are the same.
Further, the substance X ₂ may be appropriately selected from those described in the description of the solid electrolyte manufacturing equipment of the present embodiment, and is the same.

(Continuous addition of substance X ₂₎
Method for producing a solid electrolyte of this embodiment requires the addition of material X ₂ continuously. Without the addition of material X ₂ continuously decreases the dispersibility of the material X ₂ in the other ingredients, will react with other ingredients and materials X ₂ other than material X ₂ it is hardly proceeds, ionic conductivity However, excellent battery performance cannot be obtained. In the present embodiment, "adding a substance X ₂ continuously" is always other to continue adding a substance X _2, intermittently be added in several times in comparable amounts over a predetermined time (For example, a form of addition such as dropping) is also included.

The method of adding the substance X ₂ continuously is not particularly limited, and other materials other than materials X _2, is preferably added over a period time while reacting substance X _2. By such addition, more dispersed material X ₂ to the other materials other than materials X _2, is accelerated reaction with other ingredients and materials X ₂ other than material X _2, improves ionic conductivity , Better battery performance can be obtained. Moreover, the adjustment of the flow rate of material X _2, by adding over a period time, suppress an abrupt rise in temperature due to the progress of local reactions with other ingredients and materials X ₂ other than material X ₂ Therefore, safety is improved and an amorphous solid electrolyte can be stably produced.
More specifically, for example, when the reaction of the raw material containing at least lithium element, sulfur element and phosphorus element is started (the reaction device is started to start mixing, stirring, pulverization, or a treatment combining these). _{The substance X 2} can be added simultaneously or after the reaction has begun. In this embodiment, "simultaneously performed" means not only the exact meaning of performing at the same time without a difference of 1 second, but also the meaning of performing at the same time with a slight delay (for example, performing within a few seconds from the start). is there.

The time for adding a substance X _2, because different depending on the reaction time with the other ingredients and materials X ₂ other than material X _2, can not be unconditionally prescribed, for example, preferably 1 minute or more, more It is preferably 10 minutes or more, more preferably 20 minutes or more, and the upper limit is preferably 2 hours or less, more preferably 1 hour 30 minutes or less, still more preferably 1 hour or less.

The continuous addition of the substance X ₂ can be carried out, for example, by the halogen supply means of the solid electrolyte production facility of the present embodiment described above.

(reaction)
Reaction with other ingredients and materials X ₂ other than material X ₂ are mixed, stirred, it is preferable to perform the grinding or treatment a combination thereof. By performing such a treatment, the contact between the raw materials is promoted, the ionic conductivity is improved, and a solid electrolyte having better battery performance can be efficiently obtained. The process of mixing, stirring, pulverizing, or a combination thereof is the same as that described in the description of the solid electrolyte production equipment of the present embodiment, and such a process is, for example, the above-mentioned solid electrolyte of the present embodiment. It can be carried out by the reactor in the manufacturing equipment of.
Further, from the viewpoint of promoting contact between the raw materials, it is particularly preferable to carry out a treatment including pulverization, that is, pulverization, or stirring and pulverization. By performing the treatment including pulverization, the surface of the raw material is scraped, a new surface is exposed, and the new surface comes into contact with the surface of another raw material, so that the reaction between the raw materials proceeds more and the efficiency becomes higher. A solid electrolyte is often obtained.

In the present embodiment, after mixing the raw material and the solvent or the like, the raw material may be further added and mixed, and this may be repeated twice or more.
When the raw material and the solvent or the like are mixed and stirred, the raw material may be further added and mixed during and / or after the mixing and stirring, and this may be repeated twice or more. For example, the raw material and the solvent or the like may be put into a container of a ball mill or a bead mill to start mixing and stirring, and the raw material may be further put into the container during mixing and stirring, or after mixing and stirring (mixing). And after the stirring is temporarily stopped), the raw material may be put into the container and the mixing and stirring may be restarted, or the raw material may be put into the container during and after the mixing and stirring.

Further, when the raw material and the solvent or the like are mixed and pulverized, or when stirring and pulverizing, the raw material may be further added in the same manner as in the case of stirring above.
As described above, by further adding the raw materials, the number of treatments such as removal of the solvent, which is performed as needed, can be reduced, so that the solid electrolyte can be obtained more efficiently.
When further raw materials are added, a solvent may be added as needed, but the solvent may be removed when the solid electrolyte is obtained, so it is preferable to keep the addition amount to the minimum necessary.

Reaction with other ingredients and materials X ₂ other than material X ₂ in the presence of a solvent, or solvent without using can be performed. By using a solvent, which promotes more contact with other raw material and material X ₂ other than material X _2, improved ionic conductivity, but more excellent battery performance is obtained, the process of solvent the spent You will need it. On the other hand, when not using a solvent, although inferior to the contact with other ingredients and materials X ₂ other than material X ₂ as compared with the case of using a solvent, there is an advantage that processing of the solvent already used becomes unnecessary. The use or non-use of the solvent may be selected according to the situation and the like.

(solvent)
Examples of the solvent used in the present embodiment include hydrocarbon solvents such as aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, and aromatic hydrocarbon solvents; alcohol solvents, ester solvents, aldehyde solvents, ketone solvents, and the like. A solvent containing a carbon atom such as an ether solvent, a solvent containing a carbon atom and a hetero atom, and the like are preferably used.
More specifically, aliphatic hydrocarbon solvents such as hexane, pentane, 2-ethylhexane, heptane, octane, decane, undecane, dodecane and tridecane; alicyclic hydrocarbon solvents such as cyclohexane and methylcyclohexane; benzene and toluene. , Xylene, mesityrene, ethylbenzene, tert-butylbenzene, trifluoromethylbenzene, nitrobenzene, chlorobenzene, chlorotoluene, bromobenzene and other aromatic hydrocarbon solvents; ethanol, butanol and other alcohol solvents; ethyl acetate, butyl acetate and the like Ester solvent; aldehyde solvent such as formaldehyde, acetaldehyde, dimethylformamide, ketone solvent such as acetone, methyl ethyl ketone; ether solvent such as diethyl ether, dibutyl ether, tetrahydrofuran; carbon disulfide, diethyl ether, dibutyl ether, tetrahydrofuran etc. Examples thereof include a solvent containing a carbon atom and a hetero atom.

Among these, a hydrocarbon solvent is preferable, an aromatic hydrocarbon solvent is more preferable, toluene, xylene and ethylbenzene are more preferable, and toluene is particularly preferable. It is not preferable to use water as the solvent because it lowers the battery performance of the solid electrolyte.

Further, as the solvent, it is preferable to use a solvent capable of dissolving _{the substance X 2.} By selecting such a solvent, _{the direct contact between the substance X 2} and various devices such as a reaction vessel is reduced, so that corrosion of the various devices can be further suppressed. Further, when the substance X ₂ is dissolved in a solvent, the unreacted substance X ₂ can be easily removed from the solid electrolyte, and the solid electrolyte containing no or little _{substance X 2 as an impurity can be obtained.} Further, since the reaction rate is improved, a solid electrolyte can be obtained more efficiently.
As the _{solvent capable of dissolving the substance X 2} , the solvent having a solubility of the substance X ₂ is preferably 0.01% by mass or more, more preferably 0.03% by mass or more, still more preferably 0.05% by mass. The above-mentioned substances, particularly preferably 0.1% by mass or more, are used. Further, the upper limit of the solubility of the substance X ₂ is not particularly limited, and for example, the solubility of 60% by mass or less, 55% by mass or less, and 10% by mass or less can be exemplified.

Here, the measurement of the solubility of the substance X ₂ is a value measured as follows.
Substance X ₂ (2 g) was added to 3 mL of solvent and stirred at room temperature (25 ° C.) for 20 minutes. Weighed 0.1 g of the supernatant, added 1 g of an aqueous sodium thiosulfate solution (10% by mass, Na ₂ S ₂ O ₃ ) to the supernatant, and shake for about 1 minute to confirm that the coloration of the solution disappeared. .. The iodine concentration of the above solution was quantified by ICP emission spectroscopic analysis (high frequency inductively coupled plasma emission spectroscopy), and the solubility of _{substance X 2 was calculated.}

The solvent is preferably a solvent in which the alkali metal sulfide is difficult to dissolve, for example, a solvent having a solubility of the alkali metal sulfide of 1% by mass or less. When using an alkali metal sulfide as a raw material, by using such a solvent, the solubility of the solvent in the alkali metal sulfide is reduced to be consumed more efficiently react with the substance X _2, etc. it can. The solubility of the alkali metal sulfide is more preferably 0.5% by mass or less, still more preferably 0.1% by mass or less, still more preferably 0.07% by mass or less. In addition, there is no limit on the lower limit of the solubility of alkali metal sulfide.

Here, the measurement of the solubility of the alkali metal sulfide is a value measured as follows.
Alkali alkali metal sulfide was added to the solvent, and the mixture was sufficiently mixed at 20 ° C. (room temperature). It was visually observed that the alkali metal sulfide that could not be dissolved in the solvent was present in the solution. Next, inductively coupled plasma (ICP) emission spectroscopy was performed on the obtained solution using an inductively coupled plasma (ICP) emission spectroscopy analyzer. The content of the alkali metal in the obtained solution, that is, the alkali metal dissolved in the solvent was measured, and the solubility (mass%) of the alkali metal sulfide was calculated.

Such a solvent contains a carbon atom such as an aliphatic hydrocarbon solvent, an alicyclic hydrocarbon solvent, an aromatic hydrocarbon solvent and the like, which are exemplified above; a solvent containing a carbon atom and a hetero atom, and the like. Solvents are preferred.
Further, for example, when bromine (Br ₂ ) is used _{as the substance X 2} , it is substituted with an electron attracting group from the viewpoint of efficiently reacting _{bromine (Br 2) with another raw material, for example, tert-.} Solvents having a benzene ring such as butylbenzene, trifluoromethylbenzene, nitrobenzene, chlorobenzene, and chlorotoluene can be used.

The amount of the solvent used is such that the total amount of the raw material used with respect to 1 liter of the solvent is preferably 0.01 kg or more, more preferably 0.05 kg or more, and further preferably 0.2 kg or more. The upper limit is preferably an amount of 1 kg or less, more preferably 0.8 kg or less, and further preferably 0.7 kg or less. When the amount of the solvent used is within the above range, the raw materials can be reacted more smoothly.

(Solid-liquid separation)
When the reaction of the substance X ₂ with a raw material other than the substance X ₂ is carried out using a solvent, the solid electrolyte obtained by the reaction is a solid electrolyte-containing liquid accompanied by a solvent, and the solvent is removed from the solid electrolyte-containing liquid. It is preferable to do so. When it is necessary to remove the solvent, the drying treatment is usually performed, but by performing solid-liquid separation and removing the solvent to some extent in advance, it is possible to reduce the load in the drying treatment. That is, the method for producing a solid electrolyte of the present embodiment includes solid-liquid separation of the solid electrolyte-containing liquid obtained by the reaction of the _{substance X 2} with a raw material other than the _{substance X 2 using a solvent.} Is preferable.

The solid electrolyte-containing liquid mainly contains a solid electrolyte, an unreacted raw material (for example, a solid raw material such as lithium sulfide and diphosphorus pentasulfide) and the like, and mainly a solvent and an unreacted raw material (for example, substance X _2). Etc.), a liquid containing a reaction by-product and the like, and examples of the reaction by-product contained in the liquid include a sulfur-containing compound such as sulfur and an organic halogen compound, as described above. By performing solid-liquid separation, the above solid and liquid are separated.

The content of the solid electrolyte in the solid electrolyte-containing liquid varies depending on the amount of the solvent used in the reaction and cannot be unconditionally determined, but is usually about 1% by mass or more, and the upper limit is 20% by mass or less. Degree.

The solid-liquid separation is performed, for example, by decanting an apparatus for solid-liquid separation in the solid electrolyte manufacturing equipment of the present embodiment, for example, preferably a centrifuge, a vacuum filter, a decantable tank, or the like. It can be carried out by the tank to obtain.

The solid recovered by solid-liquid separation mainly contains a solid electrolyte, an unreacted raw material (for example, a solid raw material such as lithium sulfide and diphosphorus pentasulfide), but may be accompanied by a liquid. That is, it may be in the form of a slurry, and the content of the solid in the slurry is preferably 5% by mass or more, more preferably 10% by mass or more, further preferably 15% by mass or more, and the upper limit is preferably 50% by mass or less. It is more preferably 45% by mass or less, still more preferably 40% by mass or less.
If the content of solids in the slurry containing solids is within the above range by solid separation, the effect of reducing the amount of waste liquid discharged from the manufacturing equipment due to the recovery of the liquid, and the scale and cost of the equipment used for solid-liquid separation can be obtained. The balance is good.

Liquid to be recovered by solid-liquid separation is mainly solvents, unreacted starting materials (e.g., materials X _2), but is intended to include reaction by-products, the solid electrolyte, contains solid ingredients such as unreacted You may.
In addition, the content of sulfur-containing compounds such as sulfur in the liquid recovered by solid-liquid separation cannot be unconditionally determined because it varies depending on the type of raw material used and its compounding ratio, but in terms of sulfur atoms. Usually, it is about 0.1% by mass or more, and the upper limit is about 3% by mass or less.

(Drying process)
When the solid electrolyte obtained by the reaction is a solid electrolyte-containing liquid accompanied by a solvent, or is a slurry containing a solid such as a solid electrolyte obtained after the above-mentioned solid-liquid separation, the production of the solid electrolyte of the present embodiment. The method preferably further comprises drying the solid electrolyte-containing liquid or the slurry containing the solid. Further, by removing the solvent by drying the solid electrolyte-containing liquid or the slurry containing the solid, it is possible to remove sulfur which is a reaction by-product.
The drying treatment can be performed by, for example, various dryers exemplified as the drying treatment apparatus in the solid electrolyte production facility of the present embodiment described above. Further, the conditions of the drying treatment may be appropriately selected from the conditions described in the above description of the drying treatment apparatus.

(Liquid processing)
The method for producing a solid electrolyte of the present embodiment may include processing a liquid obtained from the above-mentioned solid-liquid separation apparatus. When a solvent is used, the liquid obtained from the solid-liquid separation apparatus mainly contains a solvent, but also contains the above-mentioned sulfur-containing compounds such as sulfur and reaction by-products such as organic halogen compounds. There is. As described above, since these reaction by-products cause various inconveniences, these reaction by-products can be removed when the solvent in the liquid obtained from the solid-liquid separation device is reused. preferable.
In the method for producing a solid electrolyte of the present embodiment, the liquid obtained from the device for solid-liquid separation is treated to remove the above-mentioned reaction by-products such as sulfur-containing compounds such as sulfur and organic halogen compounds. , resulting solvent, as a solvent or the like in the case of performing the reaction with other ingredients and materials X ₂ other than material X ₂ using a solvent, it is possible to effectively reused.

The liquid treatment includes, for example, a liquid phase adsorption desulfurization method and hydrogen as a method capable of removing a liquid treatment apparatus in the solid electrolyte production facility of the present embodiment, more specifically, a sulfur-containing compound such as sulfur. It can be carried out by an apparatus that employs a chemical desulfurization method, a distillation method, or the like. When the liquid after solid-liquid separation contains an organic halogen compound, it is preferable to adopt a distillation method from the viewpoint that the organic halogen compound can be removed at the same time. The liquid treatment method, the distillation conditions when the distillation method is adopted, and the like are the same as those described in the liquid treatment apparatus in the solid electrolyte production facility of the present embodiment described above.

The content of each of the sulfur-containing compound and the organic halogen compound in the liquid after removing the sulfur-containing compound and the organic halogen compound (for example, in the case of the distillation method, the flash drum and the bottom liquid of the distillation column) is the liquid. The smaller the amount, the more preferable, and usually 500 mass ppm or less, more preferably. It is 250 mass ppm or less, more preferably 100 mass ppm or less.

Further, the method for producing a solid electrolyte of the present embodiment may include reusing the solvent obtained by the treatment of the above liquid. By the treatment of the liquid, the liquid becomes a solvent from which sulfur-containing compounds and organic halogen compounds have been removed and has few impurities such as reaction by-products, so that the liquid can be reused for desired purposes. From the viewpoint of reducing the amount of waste liquid discharged from the manufacturing equipment, it is preferable to use it as a solvent in the reaction of raw materials.
The solvent obtained by the treatment of the liquid can be reused by the means for supplying the reaction apparatus in the solid electrolyte production facility of the present embodiment described above.

Further, in the method for producing a solid electrolyte of the present embodiment, from the same viewpoint as reusing the solvent obtained by the treatment of the liquid, the slurry containing the solid is dried and the removed solvent is reused. The solvent may be used as a solvent in the reaction of the raw materials.
Reusing the solvent removed by the drying treatment of the slurry containing a solid is carried out by means for supplying the solvent removed by the drying treatment device to the reaction device in the above-mentioned solid electrolyte production facility of the present embodiment. Can be done.

(Amorphous solid electrolyte)
The solid electrolyte obtained by the solid electrolyte manufacturing equipment and manufacturing method of the present embodiment is an amorphous solid electrolyte containing a lithium element, a sulfur element, a phosphorus element and a halogen element. In the present specification, the amorphous solid electrolyte is a halo pattern in which the X-ray diffraction pattern is substantially no peak other than the peak derived from the material in the X-ray diffraction measurement, and is a raw material of the solid electrolyte. It means that the presence or absence of the origin peak does not matter.

The amorphous solid electrolyte has high ionic conductivity, and can increase the output of the battery.
The solid electrolyte of the amorphous, e.g., Typical _{examples, Li 2 S-P 2 S} 5 -LiI, Li 2 S-P 2 S 5 -LiCl, Li 2 S-P 2 S 5 -LiBr _{, Li 2 S-P 2 S} 5 -LiI-LiBr, Li 2 S-P 2 S 5 -Li 2 O-LiI, Li 2 S-SiS 2 -P 2 S 5 -LiI the like. The types of elements constituting the amorphous solid electrolyte can be confirmed by, for example, an ICP emission spectrophotometer.

The shape of the amorphous solid electrolyte is not particularly limited, and examples thereof include particles. The average particle size (D ₅₀ ) of the particulate amorphous solid electrolyte can be exemplified in the range of 0.01 μm to 500 μm and 0.1 to 200 μm, for example.

(heating)
The method for producing the solid electrolyte of the present embodiment can include solid-liquid separation and, if necessary, further heating the dried solid electrolyte. By further heating, the amorphous solid electrolyte can be made into a crystalline solid electrolyte.
The heating temperature can be appropriately selected according to the structure of the amorphous solid electrolyte. For example, the amorphous solid electrolyte is raised by 10 ° C./min using a differential thermal analyzer (DTA device). Differential thermal analysis (DTA) is performed under thermal conditions, starting from the peak top of the exothermic peak observed on the lowest temperature side, preferably in the range of ± 40 ° C, more preferably ± 30 ° C, and even more preferably ± 20 ° C. Just do it.
More specifically, the heating temperature is preferably 150 ° C. or higher, more preferably 170 ° C. or higher, and even more preferably 190 ° C. or higher. On the other hand, the upper limit of the heating temperature is not particularly limited, but is preferably 300 ° C. or lower, more preferably 280 ° C. or lower, and even more preferably 250 ° C. or lower.

The heating time is not particularly limited as long as the desired crystalline solid electrolyte can be obtained, but for example, 1 minute or more is preferable, 10 minutes or more is more preferable, and 30 minutes or more is further preferable. The upper limit of the heating time is not particularly limited, but is preferably 24 hours or less, more preferably 10 hours or less, and even more preferably 5 hours or less.

Further, the heating is preferably performed in an inert gas atmosphere (for example, a nitrogen atmosphere or an argon atmosphere) or a reduced pressure atmosphere (particularly in a vacuum). This is because deterioration (for example, oxidation) of the crystalline solid electrolyte can be prevented.
The solid electrolyte can be heated by the heating device in the solid electrolyte manufacturing equipment of the present embodiment described above.

(Crystally solid electrolyte)
As described above, by heating the amorphous solid electrolyte, a crystalline solid electrolyte can be obtained. The crystalline solid electrolyte is a solid electrolyte in which a peak derived from the solid electrolyte is observed in the X-ray diffraction pattern in the X-ray diffraction measurement, and the presence or absence of a peak derived from the raw material of the solid electrolyte in these materials does not matter. Is. That is, the crystalline solid electrolyte contains a crystal structure derived from the solid electrolyte, and even if a part of the crystal structure is derived from the solid electrolyte, all of the crystal structure is derived from the solid electrolyte. It is also good. The crystalline solid electrolyte may contain an amorphous solid electrolyte as long as it has the above-mentioned X-ray diffraction pattern.

More specifically, the crystal structures of the crystalline solid electrolyte include Li ₃ PS ₄ crystal structure, Li ₄ P ₂ S ₆ crystal structure, Li ₇ PS ₆ crystal structure, 2θ = 20.2 ° and around 23. A crystal structure having a peak in the vicinity of 6 ° (for example, Japanese Patent Application Laid-Open No. 2013-16423) can be exemplified.
Here, a crystal structure having peaks in the vicinity of 2θ = 20.2 ° and in the vicinity of 23.6 ° is preferable. For example, it is a crystal structure having peaks at 2θ = 20.2 ° ± 0.3 ° and 23.6 ° ± 0.3 °.

The shape of the crystalline solid electrolyte is not particularly limited, and examples thereof include particulate forms. The average particle size (D ₅₀ ) of the particulate crystalline solid electrolyte can be exemplified in the range of 0.01 μm to 500 μm and 0.1 to 200 μm, for example.

The solid electrolyte obtained by the production method of the present embodiment has high ionic conductivity and excellent battery performance, and is suitably used for batteries. It is particularly suitable when a lithium element is used as the conductive species. The solid electrolyte obtained by the production method of the present embodiment may be used for the positive electrode layer, the negative electrode layer, or the electrolyte layer. Each layer can be produced by a known method.

Further, the battery preferably uses a current collector in addition to the positive electrode layer, the electrolyte layer and the negative electrode layer, and a known current collector can be used. For example, a layer in which a layer that reacts with the above-mentioned solid electrolyte, such as Au, Pt, Al, Ti, or Cu, is coated with Au or the like can be used.

Next, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these examples.

(Example 1)
A solid electrolyte was produced using the reactor shown in FIG. In this embodiment, "Bead Mill LMZ015" (manufactured by Ashizawa Finetech Co., Ltd.) is used as a bead mill, 485 g of zirconia balls having a diameter of 0.5 mm are charged, and 2.0 liter glass with a stirrer is used as a reaction tank. A manufacturing reactor was used.

34.77 g of lithium sulfide and 45.87 g of diphosphorus pentasulfide were added to the reaction vessel 20, and 1000 mL of dehydrated toluene was further added to prepare a slurry. The slurry charged into the reaction vessel 20 was circulated at a flow rate of 600 mL / min using a pump 54, the operation of the bead mill 10 was started at a peripheral speed of 10 m / s, and then iodine dissolved in 200 mL of dehydrated toluene (Wako Jun). 13.97 g of drug special grade) and 13.19 g of bromine (Wako pure drug special grade) were added _{from the supply facility 60 for supplying the substance X 2} to the reaction tank 20 over 30 minutes while adjusting the supply rate.
After the addition of iodine and bromine was completed, the peripheral speed of the bead mill 10 was set to 12 m / s, hot water (HW) was passed through the external circulation, and the reaction was carried out so that the discharge temperature of the pump 54 was maintained at 70 ° C. A solid electrolyte-containing liquid was prepared.

The obtained solid electrolyte-containing liquid containing an amorphous solid electrolyte, a solvent, other reaction by-products such as a sulfur-containing compound and an organic halogen compound is transferred to a decantation tank, and solid-liquid separation by decantation is performed. The obtained solid content was dried at 80 ° C. using a dryer to obtain a powdery amorphous solid electrolyte. The powdered amorphous solid electrolyte was subjected to powder X-ray analysis (XRD) measurement using an X-ray diffraction (XRD) apparatus (SmartLab apparatus, manufactured by Rigaku Co., Ltd.). It was found that there was no peak other than the peak derived from the raw material. By adding continuously over the material X ₂ fixed time, it is suppressed rapid heat generation due to reaction with other ingredients and materials X ₂ other than material X _2, safely and stably amorphous solid electrolyte Can be manufactured in.

Further, a part of the obtained powdery amorphous solid electrolyte was heated at 203 ° C. for 3 hours using a hot plate installed in the glove box.
The heated powder was subjected to powder X-ray analysis (XRD) measurement using an X-ray diffraction (XRD) apparatus (SmartLab apparatus, manufactured by Rigaku Co., Ltd.). According to the X-ray analysis spectrum, a crystallization peak was detected at 2θ = 19.9 ° and 23.6 °, and it was confirmed that a crystalline solid electrolyte was obtained. When the ionic conductivity of the obtained crystalline solid electrolyte was measured according to the following (measurement of ionic conductivity), it was 5.55 × 10 ^-3 (S / cm) and had high ionic conductivity. It was confirmed that
(Measurement of ionic conductivity)
A circular pellet having a diameter of 10 mm (cross-sectional area S: 0.785 cm ² ) and a height (L) of 0.1 to 0.3 cm was formed from a crystalline solid electrolyte to prepare a sample. Electrode terminals were taken from above and below the sample and measured by the AC impedance method at 25 ° C. (frequency range: 5 MHz to 0.5 Hz, amplitude: 10 mV) to obtain a Core-Cole plot. The real part Z'(Ω) at the point where −Z'' (Ω) is minimized near the right end of the arc observed in the high frequency side region is defined as the bulk resistance R (Ω) of the electrolyte, and the ions are according to the following equation. The conductivity σ (S / cm) was calculated.

According to the solid electrolyte manufacturing method and manufacturing equipment of the present embodiment, the manufacturing process can be simplified, and the solid electrolyte can be manufactured more safely and stably. This solid electrolyte is suitably used for batteries, especially batteries used for information-related devices such as personal computers, video cameras, mobile phones, communication devices, and the like.

Claims (6)

A reactor that produces a solid electrolyte by reacting raw materials containing lithium element, sulfur element, phosphorus element, and halogen element,
A halogen supply means for supplying at least a substance represented by the following general formula (1) as a raw material containing the halogen element, and
Solid electrolyte manufacturing equipment with.
X ₂ ... (1)
(In the general formula (1), X is a halogen element.) The equipment for producing a solid electrolyte according to claim 1, wherein the halogen supply means includes a storage tank and a supply unit for the substance. The solid electrolyte manufacturing facility according to claim 2, wherein the substance supply unit has a function of adjusting the supply rate. Claim that the reaction apparatus includes a reaction vessel and a crusher, and the halogen supply means is connected to at least one of the reaction vessel, the crusher, and a means for connecting the reaction tank and the crusher. The equipment for producing a solid electrolyte according to any one of 1 to 3. Continuously adding a substance represented by the following general formula (1) to a raw material containing at least lithium element, sulfur element and phosphorus element.
Reacting the raw material with the substance,
A method for producing a solid electrolyte including.
X ₂ ... (1)
(In the general formula (1), X is a halogen element.) The method for producing a solid electrolyte according to claim 5, wherein the substance is added while reacting the raw material with the substance.

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