Electrolyte composition, method for storage, transport, and manufacture thereof, and anti-caking agent.

Abstract

To provide an electrolyte composition that suppresses the occurrence of aggregate, and can be easily discharged from a container in a powdered electrolyte containing a sulfonylimide compound.SOLUTION: An electrolyte composition includes a powdered electrolyte containing a sulfonylimide compound represented by the general formula (1), and an anti-caking agent that prevents the caking of the powdered electrolyte, and the content of the anti-caking agent is 0.001 mass% or more and 1 mass% or less based on 100 mass% of the powdered electrolyte. LiN(R1SO2)(R2SO2) (R1 and R2 are the same or different and represent a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a fluoroalkyl group having 1 to 6 carbon atoms) (1).SELECTED DRAWING: None

Description

[Technical Field]

[0001] This disclosure relates to electrolyte compositions, methods for storing, transporting, and manufacturing the same, and anti-caking agents. [Background technology]

[0002] For example, sulfonylimide compounds such as fluorosulfonylimide salts, used in electrolytes, additives to fuel cell electrolytes, selective electrophilic fluorinators, photoacid generators, thermoacid generators, near-infrared absorbing dyes, antistatic agents, and reaction catalysts, are usually crystallized and dried, and then the resulting powder is packaged and stored or transported (shipped) as is. One way the powder is packaged for shipment is in a metal canister container. However, because sulfonylimide powder has a tendency to aggregate, if it aggregates in the container during storage or transport and the aggregate becomes larger than the container's outlet, clogging can occur, temporarily stopping the discharge of the sulfonylimide compound. In this case, for example, the discharge of the sulfonylimide compound can be restarted by striking the container from the outside with a knocker or the like until the aggregate becomes smaller than the container's outlet. Although this operation allows for the complete discharge of the powder from the canister container, it has the problem of poor workability because it requires striking as needed, and it is time-consuming to discharge from the container.

[0003] Therefore, in order to improve the storage stability when storing or transporting sulfonylimide compound powders, the applicant has proposed a packaging method other than canister containers, in which the powder is packaged in a packaging material having at least one metal layer (Patent Documents 1 and 2). The applicant has also disclosed a method for producing an electrolyte molded body by molding sulfonylimide compound powder in the specification of the application PCT / JP2022 / 008402. By forming the powder into a molded body, aggregation is suppressed and discharge from the container can be improved. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 6208929 [Patent Document 2] Patent No. 6266702 [Overview of the project] [Problems that the invention aims to solve]

[0005] Even with the above-mentioned packaging, depending on the storage period (e.g., more than one month) and the storage or transportation environment, the powder may aggregate within the packaging material, making it difficult to discharge from the packaging material. Furthermore, depending on the particle size of the molded body and the diameter of the container's outlet, bridging may occur, or the molded body may collapse due to impact during storage or transportation, causing the re-pulverized powder to aggregate, which may also make it difficult to discharge from the container.

[0006] This disclosure has been made in view of the foregoing, and its purpose is to provide an electrolyte composition containing a sulfonylime compound that suppresses the generation of aggregates and can be easily discharged from a container. [Means for solving the problem]

[0007] As a result of their investigation, the inventors of this application have found that by mixing a specific compound (agent) with a powdered electrolyte (powder) containing a sulfonylimide compound, even if the powder aggregates, solidification is suppressed, and the formation of aggregates is suppressed. Specifically, this disclosure is as follows.

[0008] The electrolyte composition disclosed herein is of general formula (1): LiN(R 1 SO2)(R 2 SO2) (R 1 and R 2 (1) It contains a powdery electrolyte containing a sulfonylimide compound represented by [general formula (1)], and an anti-caking agent for preventing caking of the powdery electrolyte, and the content of the anti-caking agent is 0.001% by mass or more and 1% by mass or less based on 100% by mass of the powdery electrolyte. The anti-caking agent is a silicon compound, general formula (2): LiPF a (C m F 2m+1 ) 6-a (a: 0 ≤ a ≤6, m: 1 ≤ m ≤4) (2) a compound represented by, general formula (3): LiBF b (C n F 2n+1 ) 4-b (b: 0 ≤ b ≤4, n: 1 ≤ n ≤4) (3) and may be at least one selected from the group consisting of a compound represented by and LiAsF6. Based on 100% by mass of the powdery electrolyte, the content of the sulfonylimide compound may be 90% by mass or more, and may also be more than 99% by mass.

[0009] The method for storing or transporting the electrolyte composition of the present disclosure may store and / or transport the electrolyte composition at a temperature of -20°C or higher and 60°C or lower, and may also store and / or transport it in a metal container.

[0010] The method for manufacturing the electrolyte composition of the present disclosure is characterized in that, based on 100% by mass of a powdery electrolyte containing a sulfonylimide compound represented by the above general formula (1), an anti-caking agent for preventing caking of the powdery electrolyte is mixed at 0.001% by mass or more and 1% by mass or less.

[0011] The anti-caking agent of the present disclosure is an anti-caking agent for preventing caking of a powdery electrolyte containing a sulfonylimide compound represented by the above general formula (1), and is characterized by containing at least one selected from the group consisting of a silicon compound, a compound represented by the above general formula (2), a compound represented by the above general formula (3), and LiAsF6 as an active ingredient.

Advantages of the Invention

[0012] According to the present disclosure, in a powdery electrolyte containing a sulfonylimide compound, it is possible to provide an electrolyte composition that suppresses the generation of aggregates and can be easily discharged from a container.

Mode for Carrying Out the Invention

[0013] Hereinafter, the present embodiment will be described in detail based on the drawings. The following description of the preferred embodiments is merely illustrative in nature and is not intended to limit the present invention, its applications, or its uses in any way.

[0014] <Electrolyte Composition> The electrolyte composition according to the present embodiment includes a powdery electrolyte and an anti-caking agent, and its form is a powder (solid). In the present specification, the powdery (powder) electrolyte means one having an average particle diameter (D50) measured by a particle size distribution measuring device preferably of 1000 μm or less, more preferably 500 μm or less. Thus, although an electrolyte composition containing an electrolyte having a fine average particle diameter is particularly likely to aggregate, caking of the electrolyte composition (during its storage or transportation) is prevented by the combined use with the anti-caking agent according to the present embodiment.

[0015] [Electrolyte] The electrolyte is a powder (solid) of a lithium salt containing a sulfonylimide compound represented by the general formula (1): [Chemical Formula 1] LiN(R 1 SO2)(R 2 SO2) (1) (hereinafter also referred to as "sulfonylimide compound (1)", a fluorine-containing sulfonylimide salt).

[0016] In the general formula (1), R 1 and R 2 are the same or different (independent of each other) and represent a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a fluoroalkyl group having 1 to 6 carbon atoms.

[0017] Examples of alkyl groups having 1 to 6 carbon atoms include methyl, ethyl, propyl, isopropyl, butyl, pentyl, and hexyl groups. Among alkyl groups having 1 to 6 carbon atoms, linear or branched alkyl groups having 1 to 6 carbon atoms are preferred, and linear alkyl groups having 1 to 6 carbon atoms are more preferred.

[0018] Examples of fluoroalkyl groups having 1 to 6 carbon atoms include those in which some or all of the hydrogen atoms of the alkyl group having 1 to 6 carbon atoms are substituted with fluorine atoms. Examples of fluoroalkyl groups having 1 to 6 carbon atoms include fluoromethyl groups, difluoromethyl groups, trifluoromethyl groups, fluoroethyl groups, difluoroethyl groups, trifluoroethyl groups, pentafluoroethyl groups, etc. In particular, the fluoroalkyl group may be a perfluoroalkyl group.

[0019] Substituent R 1 and R 2 The substituents R are preferably fluorine atoms and perfluoroalkyl groups (for example, perfluoroalkyl groups having 1 to 6 carbon atoms such as trifluoromethyl groups, pentafluoroethyl groups, and heptafluoropropyl groups), more preferably fluorine atoms, trifluoromethyl groups, and pentafluoroethyl groups, even more preferably fluorine atoms and trifluoromethyl groups, and still more preferably fluorine atoms. 1 and R 2 They may be the same, or they may be different.

[0020] Examples of sulfonylimide compounds (1) include lithium bis(fluorosulfonyl)imide (LiN(FSO2)2, also referred to as "LiFSI"), lithium bis(trifluoromethylsulfonyl)imide (LiN(CF3SO2)2, also referred to as "LiTFSI"), lithium (fluorosulfonyl)(methylsulfonyl)imide, lithium (fluorosulfonyl)(ethylsulfonyl)imide, lithium (fluorosulfonyl)(trifluoromethylsulfonyl)imide, lithium (fluorosulfonyl)(pentafluoroethylsulfonyl)imide, lithium (fluorosulfonyl)(heptafluoropropylsulfonyl)imide, lithium bis(pentafluoroethylsulfonyl)imide, and lithium bis(heptafluoropropylsulfonyl)imide. Each sulfonylimide compound (1) may be used individually or in combination of two or more types.

[0021] Among the sulfonyliimide compounds (1), LiN(FSO2)2 and LiN(CF3SO2)2 are preferred, and LiN(FSO2)2 is more preferred. In other words, the electrolyte composition is preferably one containing at least one of LiN(FSO2)2 and LiN(CF3SO2)2 as an electrolyte, and more preferably one containing LiN(FSO2)2.

[0022] The sulfonylimide compound (1) may be a commercially available product or one synthesized by a conventionally known method. The method for synthesizing the sulfonylimide compound (1) is not particularly limited, and all conventionally known methods can be used. For example, the methods described in International Publication No. 2011 / 149095, Japanese Patent Publication No. 2014-201453, Japanese Patent Publication No. 2010-168249, Japanese Patent Publication No. 2010-168308, Japanese Patent Publication No. 2010-189372, International Publication No. 2011 / 065502, Japanese Patent Publication No. Hei 8-511274, International Publication No. 2012 / 108284, International Publication No. 2012 / 117961, International Publication No. 2012 / 118063, Japanese Patent Publication No. 2010-280586, Japanese Patent Publication No. 2010-254543, Japanese Patent Publication No. 2007-182410, International Publication No. 2010 / 010613, etc. A powder (solid) of sulfonylimide compound (1) can be obtained by the conventionally known method described above.

[0023] Furthermore, the electrolyte only needs to contain sulfonylimide compound (1), but it may also contain other electrolytes (electrolytes other than sulfonylimide compound (1)). Examples of other electrolytes include imide salts and non-imide salts.

[0024] Examples of imide salts include other fluorine-containing sulfonylimide salts different from sulfonylimide compound (1) (hereinafter referred to as "other sulfonylimide compounds"). Examples of other sulfonylimide compounds include non-lithium salts of the fluorine-containing sulfonylimides listed as sulfonylimide compound (1) (for example, salts obtained by substituting lithium (ions) with cations other than lithium ions in sulfonylimide compound (1)). Examples of salts substituted with cations other than lithium ions include alkali metal salts such as sodium salts, potassium salts, rubidium salts, and cesium salts; alkaline earth metal salts such as beryllium salts, magnesium salts, calcium salts, strontium salts, and barium salts; aluminum salts; ammonium salts; and phosphonium salts. Other sulfonylimide compounds may be used individually or in combination of two or more. In addition, other sulfonylimide compounds may be commercially available or synthesized by conventionally known methods.

[0025] Examples of nonimide salts include salts of nonimide anions and cations (lithium ions and the cations exemplified above). Examples of nonimide salts include those with general formula (2): [C2] LiPF a (C m F 2m+1 ) 6-a (a:0≦a≦6, m:1≦m≦4) (2) A compound represented by (hereinafter referred to as "fluorophosphate compound (2)"), general formula (3): [C3] LiBF b (C n F 2n+1 ) 4-b (b:0≦b≦4, n:1≦n≦4) (3) Examples include compounds represented by (hereinafter referred to as "fluoroboric acid compounds (3)"), lithium salts such as lithium arsenate hexafluoride (LiAsF6), LiSbF6, LiClO4, LiSCN, LiAlF4, CF3SO3Li, LiC[(CF3SO2)3], LiN(NO2), and LiN[(CN)2]; and non-lithium salts (for example, salts in which lithium (ions) are substituted with the exemplified cations in these lithium salts (e.g., NaBF4, NaPF6, NaPF3(CF3)3, etc.). Non-imide salts may be used individually or in combination of two or more types. Furthermore, non-imide salts may be commercially available or synthesized by conventionally known methods.

[0026] Among other electrolytes, non-imide salts are preferred from the viewpoint of ionic conductivity and cost, with fluorophosphate compounds (2), fluoroboric acid compounds (3), and LiAsF6 being preferred, and fluorophosphate compounds (2) being more preferred.

[0027] Examples of fluorophosphate compounds (2) include LiPF6, LiPF3(CF3)3, LiPF3(C2F5)3, LiPF3(C3F7)3, and LiPF3(C4F9)3. Among the fluorophosphate compounds (2), LiPF6 and LiPF3(C2F5)3 are preferred, with LiPF6 being more preferred.

[0028] Examples of fluoroboric acid compounds (3) include LiBF4, LiBF(CF3)3, LiBF(C2F5)3, and LiBF(C3F7)3. Among the fluoroboric acid compounds (3), LiBF4 and LiBF(CF3)3 are preferred, with LiBF4 being more preferred.

[0029] The electrolyte salt composition may be an electrolyte salt with a single salt composition of sulfonylimide compound (1), or an electrolyte salt with a mixed salt composition containing sulfonylimide compound (1) and other electrolytes. When using an electrolyte salt with a mixed salt composition, an electrolyte salt with a mixed salt composition containing sulfonylimide compound (1) and fluorophosphate compound (2) is preferred, an electrolyte salt with a mixed salt composition containing at least one of LiN(FSO2)2 and LiN(CF3SO2)2 and LiPF6 is more preferred, and an electrolyte salt with a mixed salt composition containing LiN(FSO2)2 and LiPF6 is particularly preferred.

[0030] The content of sulfonylimide compound (1) relative to the powdered electrolyte (100% by mass) (total content if two or more types are included) is preferably 90% by mass or more, more preferably 95% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more, with a particularly preferable value being greater than 99% by mass. The upper limit of this content is 100% by mass. In other words, the electrolyte may contain only sulfonylimide compound (1).

[0031] When other electrolytes are included, the content of other electrolytes (total content if two or more types are included) relative to the powdered electrolyte (100% by mass) is preferably greater than 1% by mass, and the upper limit is preferably 10% by mass or less.

[0032] [Anti-caking agent] The anti-caking agent according to this embodiment is an agent that prevents caking of a powdered electrolyte containing a sulfonylimide compound (1). When the anti-caking agent is added to the sulfonylimide compound (1) powder, even if the powder aggregates, it is less likely to caking, and the generation of aggregates is suppressed. As a result, the powder of the electrolyte composition containing the sulfonylimide compound (1) and the anti-caking agent can be easily discharged from the container after being stored in the container for a predetermined period or after transportation, without the need for impact. In this specification, the property of the electrolyte composition powder in which the generation of aggregates is suppressed is also referred to as "cohesiveness." Furthermore, the property of the electrolyte composition powder in which it can be easily discharged from the container (for example, by the weight of the powder itself) without the need for impact is also referred to as "dischargeability."

[0033] The anti-caking agent contains at least one active ingredient selected from the group consisting of silicon compounds, compounds represented by general formula (2), compounds represented by general formula (3), and LiAsF6. Each anti-caking agent may be used alone, or two or more may be used in combination. That is, the anti-caking agent may contain only one of the silicon compounds, compounds represented by general formula (2), compounds represented by general formula (3), and LiAsF6, or it may contain two or more.

[0034] (Silicon compounds) As for silicon compounds, the specific surface area is 100 m². 2 / g~500m 2 / g, preferably 150m 2 / g~400m 2Examples include silicon dioxide compounds (powder) such as fumed silica (dry silica, preferably hydrophobic fumed silica), spherical silica, and their trimethylsilylated derivatives (organic silica particles). Examples of fumed silica include those hydrophobized with organochlorosilanes, polyorganosiloxanes, hexamethyldisilazane, etc. Specific examples of fumed silica include commercially available products such as the AEROSIL® series from Nippon Aerosil Co., Ltd. and the HDK® series of highly dispersed silica from Asahi Kasei Wacker Silicone Co., Ltd. Silicon compounds may be used individually or in combination of two or more types.

[0035] (Compounds represented by general formula (2), compounds represented by general formula (3), and LiAsF6) The compound represented by general formula (2), the compound represented by general formula (3), and LiAsF6 are, respectively, the fluorophosphate compound (2), the fluoroboric acid compound (3), and LiAsF6, which are examples of other electrolytes (non-imide salts). That is, the electrolyte composition may contain these compounds not as electrolytes, but as anticaking agents. Hereinafter, the fluorophosphate compound (2), the fluoroboric acid compound (3), and LiAsF6 contained as anticaking agents will also be referred to as "non-silicon compounds" (anticaking agents other than silicon compounds). Non-silicon compounds may be used individually, or two or more may be used in combination.

[0036] Among anticaking agents, silicon compounds and fluorophosphate compounds (2) are preferred from the viewpoint of improving the cohesiveness and discharge properties of the electrolyte composition, and fumed silica and LiPF6 are more preferred.

[0037] The content of the anti-caking agent (total content if two or more types are included) is 0.001% by mass or more and 1% by mass or less per 100% by mass of the powdered electrolyte, from the viewpoint of improving the cohesiveness and dischargeability of the electrolyte composition. The content is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, per 100% by mass of the powdered electrolyte, and the upper limit is preferably 0.8% by mass or less, more preferably 0.5% by mass or less.

[0038] When a non-silicon compound is included as an anti-caking agent, the content of the non-silicon compound (total content if two or more types are included) is 0.001% by mass or more and 1% by mass or less per 100% by mass of sulfonylimide compound (1), from the viewpoint of improving the cohesiveness and dischargeability of the electrolyte composition. The content is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, per 100% by mass of sulfonylimide compound (1), and the upper limit is preferably 0.8% by mass or less, more preferably 0.5% by mass or less. When at least one of fluorophosphate compound (2), fluoroboric acid compound (3), and LiAsF6 is included as an electrolyte (other electrolyte), the content of the other electrolyte relative to 100% by mass of sulfonylimide compound (1) is usually a value sufficiently larger than the upper limit of the non-silicon compound content (1% by mass or less) (for example, more than 1% by mass and 10% by mass or less). In other words, when at least one of fluorophosphate compounds (2), fluoroboric acid compounds (3), and LiAsF6 is included as an anti-caking agent, the amount is limited to a trace amount compared to when it is included as an electrolyte (other electrolyte).

[0039] When using an electrolyte solution made by dissolving the electrolyte composition discharged from the container in a solvent, the anti-caking agent is difficult to dissolve, so the electrolyte solution should be filtered as needed. In this case, electrolyte compositions containing more than 1% by mass of the anti-caking agent may cause problems with poor filterability (due to inadequate filtration).

[0040] <Method for producing electrolyte composition> The method for producing the electrolyte composition according to this embodiment involves mixing a powdered electrolyte containing a sulfonylimide compound (1) and, optionally, other electrolytes, with an anti-caking agent containing a silicon compound and / or a non-silicon compound in an amount of 0.001% to 1% by mass per 100% by mass of the powdered electrolyte. If the anti-caking agent contains a non-silicon compound, the non-silicon compound is mixed in an amount of 0.001% to 1% by mass per 100% by mass of the sulfonylimide compound (1).

[0041] The method for adding an anti-caking agent to the sulfonyliimide compound (1) powder and mixing it can be any conventionally known method as appropriate. Since the resulting electrolyte composition is hygroscopic, the mixing process should be carried out under low dew point conditions, for example, at a dew point of -30°C or lower.

[0042] <Storage or transportation method for electrolyte compositions> The method for storing or transporting the electrolyte composition according to this embodiment is to store or transport the electrolyte composition in a container.

[0043] (container) As for the container, a sealed container is preferred. The sealed container is preferably made of a material and structure that makes it difficult for moisture to enter, more preferably highly airtight that can maintain the internal pressure of the container, and even more preferably one that can be sealed (closed system). Examples of means for making the container sealable include providing a valve in part of the container.

[0044] The material of the sealed container (the material of the part that comes into contact with the contents (electrolyte composition)) is not particularly limited and includes metals such as stainless steel (SUS316, etc.), aluminum, aluminum alloys, and Hastelloy®; fluororesins such as tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (perfluoroalkoxyalkane, PFA) and polytetrafluoroethylene (PTFE); olefin resins such as polyethylene (PE) and polypropylene (PP); and glass. Among sealed containers, metal containers and fluororesin containers are preferred, and stainless steel containers and PFA containers are more preferred.

[0045] Furthermore, the inner surface of the sealed container made of the aforementioned metal material may be coated with a resin. The resin used for coating is not particularly limited, and examples include fluororesins (PTFE, PFA, tetrafluoroethylene-hexafluoropropylene copolymer (FEP), etc.) and olefin resins (PP, etc.).

[0046] The structure of the sealed container can include canisters, plastic containers, fluoropolymer containers, pouch-type containers, etc. The sealed container may also consist of a resin inner bag and a metal outer casing. The shape of the sealed container is not particularly limited and can include bottle-type, cylindrical, aluminum-lined paper carton-type, aluminum pouch-type, etc. The volume of the sealed container is not particularly limited and is approximately 100L to 20000L.

[0047] The temperature at which the electrolyte composition is stored and / or transported (the internal temperature of the sealed container during storage and / or transport) is preferably between -20°C and 60°C. The lower limit of this temperature may be -10°C or higher, 0°C or higher, or 10°C or higher, and the upper limit may be 50°C or lower, or 40°C or lower. By appropriately adjusting and controlling this temperature, the formation of aggregates during storage and / or transport can be further suppressed (improved coagulation).

[0048] <Application> The electrolyte composition of this disclosure can be used, for example, in batteries (batteries having a charge / discharge mechanism), energy storage (electrochemical) devices (or materials for ion conductors constituting these), etc. Specifically, the electrolyte composition can be used as an electrolyte constituting, for example, primary batteries, secondary batteries (e.g., lithium (ion) secondary batteries), fuel cells, electrolytic capacitors, electric double-layer capacitors, solar cells, electrochromic display elements, etc. [Examples]

[0049] The present disclosure will be described below based on examples. However, the present disclosure is not limited to the following examples, and the following examples can be modified or changed in accordance with the spirit of the present disclosure, and such modifications do not exclude them from the scope of the present disclosure.

[0050] (Example 1) At a temperature of 25°C, 300.10 g of lithium bis(fluorosulfonyl)imide (manufactured by Nippon Shokubai Co., Ltd., LiN(FSO2)2, hereinafter referred to as "LiFSI") as the sulfonyliimide compound (1) and 0.90 g of fumed silica (manufactured by Nippon Aerosil Co., Ltd., AEROSIL® RX200) as an anti-caking agent were mixed to obtain a LiFSI composition (electrolyte composition). Subsequently, 250 g of the LiFSI composition was placed in a 100 mL beaker, a 2.5 kg weight was placed on top, and the beaker was stored in an open state for one month. After one month of storage, the dischargeability and coagulation properties of the LiFSI composition from the beaker were evaluated based on the following evaluation criteria. The results are shown in Table 1 below.

[0051] (emission) Dischargeability was evaluated as follows: "○" if the LiFSI composition was discharged by its own weight when the weight was removed and the beaker was inverted, and "×" if it was not discharged by its own weight.

[0052] (cohesion) Coagulation was evaluated by visually observing the discharged LiFSI composition. If no aggregates were observed, it was marked as "○" (no aggregation), and if aggregates were observed, it was marked as "×".

[0053] (Example 2) A LiFSI composition was prepared, stored, and evaluated in the same manner as in Example 1, except that 300.23 g of LiFSI and 0.31 g of fumed silica were used.

[0054] (Example 3) A LiFSI composition was prepared, stored, and evaluated in the same manner as in Example 1, except that 300.12 g of LiFSI and 0.90 g of LiPF6 (manufactured by Stella Chemifa Co., Ltd.) as an anti-caking agent were used.

[0055] (Example 4) LiFSI compositions were prepared, stored, and evaluated in the same manner as in Example 1, except that 300.42 g of LiFSI and 60.31 g of LiPF were used.

[0056] (Comparative Example 1) The evaluation was carried out in the same manner as in Example 1, except that 250g of LiFSI was placed in a 100mL beaker, a 2.5kg weight was placed on top of it, and it was stored in an open state for one month.

[0057] [Table 1]

[0058] Table 1 shows that, comparing each example with the comparative example, the LiFSI compositions of each example exhibited excellent dischargeability and coagulation even after being stored for one month in an open state under load from weights. In other words, it was found that by including a specific amount of anti-caking agent in the LiFSI powder, the generation of aggregates was suppressed, and as a result, the LiFSI composition could be easily discharged from the container.

[0059] In Examples 3 and 4, it was found that the same effect as described above could be achieved by including LiPF6, which is commonly used as an electrolyte, in the LiFSI powder at a smaller amount than the usual amount when it is included as an electrolyte. In other words, it was found that other electrolytes such as LiPF6 used with LiFSI can act as anti-caking agents by adjusting their content relative to the LiFSI powder to a specific amount. [Industrial applicability]

[0060] The electrolyte composition of this disclosure is useful as a form or content when storing or transporting powdered electrolytes containing sulfonylimide compounds in a container.

Claims

1. A powdered electrolyte containing a sulfonyliimide compound represented by general formula (1), The above-mentioned powdered electrolyte contains an anti-caking agent to prevent caking, The content of the above anti-caking agent is 0.001% by mass or more and 1% by mass or less, based on 100% by mass of the above powdered electrolyte. The electrolyte composition is characterized in that the above-mentioned anti-caking agent is at least one selected from the group consisting of silicon compounds, compounds represented by general formula (2), compounds represented by general formula (3), and LiAsF6. LiN(R) １ SO ２ ) (Caution ２ SO ２ ) (Note １ and R ２ (1) LiPF a (C m F 2m+1) 6-a (a: 0≦a≦6, m:1≦m≦4) (2) LiBF b (C n F 2n+1 ) 4-b (b: 0≦b≦4, n:1≦n≦4) (3)

2. The electrolyte composition according to claim 1, characterized in that the sulfonylimide compound is contained in an amount of 90% by mass or more of the above-mentioned powdered electrolyte (100% by mass).

3. The electrolyte composition according to claim 1, characterized in that the content of the sulfonylimide compound is greater than 99% by mass with respect to 100% by mass of the powdered electrolyte.

4. A method for storing or transporting an electrolyte composition, characterized by storing and / or transporting the electrolyte composition according to any one of claims 1 to 3 at a temperature of -20°C or higher and 60°C or lower.

5. The method for storing or transporting an electrolyte composition according to claim 4, characterized in that the electrolyte composition is stored and / or transported in a metal container.

6. An anti-caking agent for preventing caking of powdered electrolytes containing a sulfonylimide compound represented by general formula (1), Silicon compounds, compounds represented by general formula (2), compounds represented by general formula (3), and LiAsF ６ An anti-caking agent characterized by containing at least one selected from the group consisting of the following as an active ingredient. LiN(R １ SO ２ )(R ２ SO ２ )(R １ and R ２ are the same or different and represent a fluorine atom, an alkyl group having 1 to 6 carbon atoms, or a fluoroalkyl group having 1 to 6 carbon atoms.) (1) LiPF ａ (C ｍ F ２ｍ＋１ ) ６－ａ (a:0≦a≦6、m:1≦m≦4) (2) LiBF ｂ (C ｎ F ２ｎ+１ ) ４－ｂ (b:0≦b≦4、n:1≦n≦4) (3)

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