JP7573355B2 - Apparatus for producing non-aqueous electrolyte and method for producing non-aqueous electrolyte - Google Patents

Description

The present invention relates to a non-aqueous electrolyte manufacturing apparatus and a non-aqueous electrolyte manufacturing method.

In lithium ion batteries, a non-aqueous electrolyte solution in which a lithium-based electrolyte such as lithium hexafluorophosphate (LiPF ₆ ) is dissolved in an organic non-aqueous solvent is used as the electrolyte solution.

However, trace amounts of water remain in the solvent and lithium-based electrolyte constituting the electrolytic solution. This water reacts with the lithium-based electrolyte such as _LiPF6 to produce hydrogen fluoride (HF) and the like, for example, as shown in the following reaction formulas (1) to (3).
(1) LiPF ₆ +H ₂ O → LiF+2HF+POF ₃
(2) POF ₃ +H ₂ O → POF ₂ (OH) + HF
(3) POF ₂ (OH) + H ₂ O → POF (OH) ₂ +HF

If acidic impurities such as hydrogen fluoride (hydrofluoric acid) are present in the electrolyte, they can reduce the battery capacity and charge/discharge cycle characteristics of the lithium-ion battery, and can easily cause corrosion inside the battery (see Patent Document 1 (JP 2011-71111 A)).

JP 2011-71111 A

For this reason, there has been a demand for a method for removing acidic impurities such as hydrofluoric acid from the electrolyte. One possible method for removing such acidic impurities is to bring the lithium-ion battery electrolyte into contact with a weakly basic anion exchange resin that contains an anion exchange group having a tertiary amine structure (a tertiary amino group).

However, the present inventors have found through their investigations that when the weakly basic anion exchange resin is brought into contact with an electrolyte for a lithium ion battery, a quaternization reaction occurs in which the tertiary amino group is modified into a quaternary ammonium group by the carbonate solvent in the electrolyte.
When the anion exchange group is modified by the above-mentioned quaternization reaction, the adsorptivity is improved and the group becomes more likely to adsorb not only acidic impurities in the electrolyte but also other components, making it difficult to selectively remove the acidic impurities.

In light of this situation, the present invention aims to provide a nonaqueous electrolyte manufacturing apparatus that can easily purify nonaqueous electrolytes, such as electrolytes for lithium ion batteries, by adsorbing acidic impurities such as hydrofluoric acid contained in the nonaqueous electrolytes using a weakly basic anion exchange resin having amino groups while effectively suppressing the degeneration of the weakly basic anion exchange groups, tertiary amino groups, into quaternary ammonium groups, and to provide a method for manufacturing nonaqueous electrolytes.

As a result of intensive research conducted by the inventors in order to achieve the above object, they discovered that the above technical problems can be solved by a non-aqueous electrolyte manufacturing apparatus having an ion exchange section containing a weakly basic anion exchange resin for obtaining a non-aqueous electrolyte by passing an alkali metal salt electrolyte-containing liquid in which an alkali metal salt electrolyte is dispersed in a carbonate ester, the weakly basic anion exchange resin having a styrene-based resin base and a tertiary amino group as a weakly basic anion exchange group, and having a total ion exchange capacity of 0.1 to 3.0 eq/L-R before treatment with the alkali metal salt electrolyte-containing liquid, and they have completed the present invention based on this finding.

That is, the present invention provides
(1) An ion exchange unit containing a weakly basic anion exchange resin is provided for passing an alkali metal salt electrolyte-containing liquid in which an alkali metal salt electrolyte capable of decomposing into a carbonate ester to generate an acid is dissolved , to obtain a nonaqueous electrolyte solution.
the weakly basic anion exchange resin has a styrene-based resin as a base, a tertiary amino group as a weakly basic anion exchange group, and a total ion exchange capacity before treatment with an alkali metal salt electrolyte-containing liquid of 0.1 to 3.0 eq/L-R;
(2) The apparatus for producing a non-aqueous electrolyte according to (1) above, wherein the styrene-based resin is a styrene-divinylbenzene copolymer.
(3) The apparatus for producing a non-aqueous electrolyte according to (1) or (2), wherein the non-aqueous electrolyte is an electrolyte for a lithium ion battery.
(4) A method for producing a nonaqueous electrolyte solution, comprising the steps of:
an acid adsorption step of passing an alkali metal salt electrolyte-containing liquid, in which an alkali metal salt electrolyte capable of being decomposed into a carbonate ester to generate an acid , through an ion exchange unit containing a weakly basic anion exchange resin to obtain nonaqueous electrolysis;
a method for producing a non-aqueous electrolyte solution, wherein the weakly basic anion exchange resin has a styrene-based resin as a base, a tertiary amino group as a weakly basic anion exchange group, and a total ion exchange capacity before treatment with an alkali metal salt electrolyte-containing liquid of 0.1 to 3.0 eq/L-R;
(5) The method for producing a non-aqueous electrolyte according to the above (4), wherein the styrene-based resin is a styrene-divinylbenzene copolymer.
(6) The method for producing a non-aqueous electrolyte solution according to (4) or (5), wherein the non-aqueous electrolyte solution is an electrolyte solution for a lithium ion battery.
This provides:

The present invention provides a nonaqueous electrolyte manufacturing apparatus that can easily purify nonaqueous electrolytes by adsorbing acidic impurities such as hydrofluoric acid contained in the nonaqueous electrolyte with a weakly basic anion exchange resin having amino groups while effectively suppressing the degeneration of the weakly basic anion exchange groups, tertiary amino groups, into quaternary ammonium groups, and can also provide a method for manufacturing nonaqueous electrolytes.

FIG. 2 is a diagram illustrating a configuration of an apparatus for producing a nonaqueous electrolyte according to the present invention. 1 is a diagram showing an example of an apparatus for producing a nonaqueous electrolyte according to the present invention;

The apparatus for producing a non-aqueous electrolyte according to the present invention includes an ion exchange unit containing a weakly basic anion exchange resin, and configured to pass an alkali metal salt electrolyte-containing liquid in which an alkali metal salt electrolyte is dispersed in a carbonate ester to obtain a non-aqueous electrolyte,
The weakly basic anion exchange resin is characterized in that it has a styrene-based resin as a base, has a tertiary amino group as a weakly basic anion exchange group, and has a total ion exchange capacity of 0.1 to 3.0 eq/L-R before treatment with an alkali metal salt electrolyte-containing liquid.

Figure 1 shows an example of the configuration of a nonaqueous electrolyte manufacturing device according to the present invention.

As shown in FIG. 1, the nonaqueous electrolyte manufacturing apparatus 1 according to the present invention has an ion exchange section 2 containing a weakly basic anion exchange resin for passing an alkali metal salt electrolyte-containing liquid S in which an alkali metal salt electrolyte such as a lithium-based electrolyte is dispersed in a carbonate ester to obtain a nonaqueous electrolyte.

In the non-aqueous electrolyte manufacturing apparatus according to the present invention, the carbonate ester may be one or more selected from cyclic carbonate esters and chain carbonate esters.

Examples of cyclic carbonate esters include one or more selected from ethylene carbonate (ethylene carbonate), propylene carbonate (propylene carbonate), etc., and examples of chain carbonate esters include one or more selected from dimethyl carbonate (dimethyl carbonate), diethyl carbonate (diethyl carbonate), ethyl methyl carbonate (ethyl methyl carbonate), etc.

In the non-aqueous electrolyte manufacturing apparatus of the present invention, the alkali metal salt electrolyte may be a lithium-based electrolyte, and the lithium-based electrolyte may be one or more selected from _LiPF6 , _LiClO4 , _LiBF4 , _LiAsF6 , _LiSbF6 , _LiAlCl4 , _{LiCF3SO3 ,} etc., with _LiPF6 being preferred in terms of battery performance.
In the non-aqueous electrolyte production apparatus according to the present invention, the non-aqueous electrolyte is preferably an electrolyte for lithium ion batteries.

In the nonaqueous electrolyte manufacturing apparatus according to the present invention, the concentration of the alkali metal salt in the alkali metal salt electrolyte-containing solution is preferably 0.5 to 2.0 mol/L, more preferably 0.5 to 1.2 mol/L, and even more preferably 0.8 to 1.2 mol/L.

The method for preparing the alkali metal salt electrolyte-containing liquid is not particularly limited, but it can be prepared, for example, by adding and dissolving an alkali metal salt electrolyte in a carbonate ester under an inert gas atmosphere.

The non-aqueous electrolyte manufacturing device according to the present invention has an ion exchange section that contains a weakly basic anion exchange resin and through which an alkali metal salt electrolyte-containing liquid (unrefined non-aqueous electrolyte) is passed.

In the nonaqueous electrolyte manufacturing apparatus according to the present invention, the weakly basic anion exchange resin used in the ion exchange section has a styrene-based resin as the base.

In this application, styrene-based resin means a resin containing 50% by mass or more of structural units derived from styrene or a styrene derivative, either homopolymerized or copolymerized with styrene or a styrene derivative.

The styrene derivative may be one or more selected from α-methylstyrene, vinyltoluene, chlorostyrene, ethylstyrene, i-propylstyrene, dimethylstyrene, bromostyrene, etc.

As long as the styrene-based resin is mainly composed of a homopolymer or copolymer of styrene or a styrene derivative, it may be a copolymer with other copolymerizable vinyl monomers. Examples of such vinyl monomers include polyfunctional monomers such as divinylbenzenes, such as o-divinylbenzene, m-divinylbenzene, and p-divinylbenzene, alkylene glycol di(meth)acrylates, such as ethylene glycol di(meth)acrylate and polyethylene glycol di(meth)acrylate, (meth)acrylonitrile, methyl (meth)acrylate, and the like.

The other copolymerizable vinyl monomers are preferably ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate having an ethylene polymerization number of 4 to 16, and divinylbenzene, more preferably divinylbenzene and ethylene glycol di(meth)acrylate, and even more preferably divinylbenzene.

In the non-aqueous electrolyte manufacturing apparatus according to the present invention, the weakly basic anion exchange resin used in the ion exchange section has a tertiary amino group as the weakly basic anion exchange group.

（ただし、Ｒ¹基およびＲ²基は炭素数１～３の炭化水素基であって互いに同一であっても異なっていてもよく、＊は基体または基体へ結合するための結合基との結合部位を示す。）
で表されるものを挙げることができる。 The tertiary amino group is represented by the following general formula (I):

(wherein ^R1 and ^R2 are hydrocarbon groups having 1 to 3 carbon atoms and may be the same or different, and * indicates a bonding site with a substrate or a bonding group for bonding to a substrate.)
Examples of the above-mentioned formulas are given below.

In the weakly basic anion exchange group represented by the above general formula (I), the R ¹ group and the R ² group are hydrocarbon groups having 1 to 3 carbon atoms.
The R ¹ group or R ² group may be one or more groups selected from an alkyl group and an alkenyl group, and is preferably an alkyl group.
Specific examples of the R ¹ group or R ² group include one or more groups selected from a methyl group, an ethyl group, a propyl group, and a propylene group, and a methyl group is preferable.
In the weakly basic anion exchange group represented by the above general formula (I), the R ¹ group and the R ² group may be the same or different.

Examples of the weakly basic anion exchange group represented by the above general formula (I) include a dimethylamino group, a diethylamino group, a dipropylamino group, etc., and the dimethylamino group is preferable.

In the above general formula (I), * indicates the binding site between the weakly basic anion exchange group represented by the above general formula (I) and the substrate or the binding group for binding to the substrate.

（ただし、Ｒ¹基およびＲ²基は炭素数１～３の炭化水素基であって互いに同一であっても異なっていてもよく、Ｒ³基は炭素数１～３の炭化水素基であり、＊は基体との結合部位を示す。） The weakly basic anion exchange group represented by the above general formula (I) is preferably bonded to the substrate made of a styrene-based resin via an appropriate bonding group, ^R3 group, as shown in the following general formula (II).

(wherein ^R1 and ^R2 are hydrocarbon groups having 1 to 3 carbon atoms and may be the same or different, ^R3 is a hydrocarbon group having 1 to 3 carbon atoms, and * indicates the bonding site with the substrate.)

The R ¹ group and R ² group may be the same as those mentioned above.
The R ³ group is a hydrocarbon group having 1 to 3 carbon atoms, and examples of the R ³ group include one or more groups selected from alkylene groups and alkenylene groups, with an alkylene group being preferred.
Specific examples of the R ³ group include one or more groups selected from the group consisting of a methylene group (--CH ₂ --), an ethylene group (--CH ₂ CH ₂ CH ₂ --), a propylene group (--CH ₂ CH ₂ CH ₂ --), and the like, with a methylene group being preferred.

The weakly basic anion exchange group represented by the above general formula (I) can be introduced into a styrene-based resin by introducing it as a substituent into styrene or a styrene derivative.

In the non-aqueous electrolyte manufacturing apparatus according to the present invention, the weakly basic anion exchange resin used in the ion exchange section has a total ion exchange capacity of 0.1 to 3.0 eq/L-R before treatment with the alkali metal salt electrolyte-containing liquid.

In the non-aqueous electrolyte manufacturing apparatus according to the present invention, the weakly basic anion exchange resin used in the ion exchange section has a total ion exchange capacity of 0.1 to 3.0 eq/L-R before treatment with the alkali metal salt electrolyte-containing liquid, preferably 0.5 to 2.5 eq/L-R, and more preferably 1.0 to 2.0 eq/L-R.

In the present application, the total ion exchange capacity means a value calculated by the method described below.
In a weakly basic anion exchange resin in which amino groups serve as the weakly basic anion exchange groups, the total ion exchange capacity refers to the combined ion exchange capacity of primary amino groups, secondary amino groups, tertiary amino groups and quaternary ammonium groups.

The nonaqueous electrolyte manufacturing apparatus according to the present invention employs a weakly basic anion exchange resin that is based on a styrene-based resin, has a tertiary amino group as a weakly basic anion exchange group, and has a total ion exchange capacity within the above range before treatment with an alkali metal salt electrolyte-containing liquid. This allows for easy purification when acidic impurities such as hydrofluoric acid contained in an alkali metal salt electrolyte-containing liquid are adsorbed and purified by the weakly basic anion exchange resin that has an amino group, while effectively suppressing the degeneration of the tertiary amino group, which is a weakly basic anion exchange group, into a quaternary ammonium group.

In this application, the total ion exchange capacity is defined as the sum of the amino group exchange capacity and the neutral salt decomposition capacity, where the anion exchange resin is a weak base anion exchange resin in a wet state before treatment with an alkali metal salt electrolyte-containing liquid, the anion exchange resin is completely converted to the chloride ion form with hydrochloric acid, the excess hydrochloric acid is washed away with ethanol, and the amount of chloride ions that flow out when ammonia water is passed through is defined as the amino group exchange capacity, and the amount of chloride ions that flow out when a sodium nitrate solution is then passed through is defined as the neutral salt decomposition capacity.

The weakly basic anion exchange resin contained in the ion exchange section may have any of a gel type structure, a macroporous (MR) type structure, and a porous type structure, with a macroporous type structure being preferred.

The size of the weakly basic anion exchange resin is not particularly limited, but the harmonic mean diameter is preferably
The thickness is preferably 300 to 1000 μm, more preferably 400 to 800 μm, and even more preferably 500 to 700 μm.

Such weakly basic anion exchange resins may be commercially available products, for example, one or more selected from Diaion WA30 manufactured by Mitsubishi Chemical Corporation and ORLITE DS-6 manufactured by Organo Corporation.

In the non-aqueous electrolyte manufacturing apparatus according to the present invention, the form of the weakly basic anion exchange resin contained in the ion exchange unit is not particularly limited as long as it allows contact between the alkali metal salt electrolyte-containing liquid and the weakly basic anion exchange resin.
For example, the ion exchange unit may be a column or tank packed with a weakly basic anion exchange resin through which the alkali metal salt electrolyte-containing liquid can pass.
The ion exchange unit may also be provided with a pump for passing the alkali metal salt electrolyte-containing liquid.

In the nonaqueous electrolyte manufacturing apparatus according to the present invention, the liquid passing speed (liquid hourly space velocity) at which the alkali metal salt electrolyte-containing liquid is passed through the weakly basic anion exchange device in the ion exchange section may be appropriately selected from the speed at which acidic impurities in the alkali metal salt electrolyte-containing liquid can be removed.

In the treatment with the weakly basic anion exchange resin, for example, first, the weakly basic anion exchange resin is washed in advance with the carbonate ester solvent constituting the alkali metal salt electrolyte-containing liquid to be treated, and then dried under reduced pressure at about 40 to 80° C., and then the weakly basic anion exchange resin is swelled again with the carbonate ester solvent constituting the alkali metal salt electrolyte-containing liquid to be treated, and then packed into a column.
Then, backwashing, extrusion, etc. are performed according to the usual method, and the electrolyte to be treated is passed through the ion exchange resin preferably at an SV (flow rate/volume ratio of ion exchange resin) of 1 to 100 hr ^-1 , more preferably at an SV of 2 to 50 hr ^-1 , and even more preferably at an SV of 5 to 20 hr ^-1 .

In the nonaqueous electrolyte manufacturing apparatus according to the present invention, the content of acidic impurities such as hydrofluoric acid in the acid adsorption treatment solution obtained from the ion exchange unit is preferably 20 ppm by mass or less, more preferably 10 ppm by mass or less, and even more preferably 5 ppm by mass or less.
In the present application, the amount of acidic impurities refers to a value measured by neutralization titration.

According to the present invention, by adopting a weakly basic anion exchange resin contained in the ion exchange section that has a styrene-based resin as a base, has tertiary amino groups as weakly basic anion exchange groups, and has a total ion exchange capacity calculated by the above formula within the above range, it is possible to provide a nonaqueous electrolyte manufacturing device that can easily perform purification processing while effectively suppressing the degeneration of the tertiary amino groups, which are weakly basic anion exchange groups, into quaternary ammonium groups when adsorbing and purifying acidic impurities such as hydrofluoric acid contained in the nonaqueous electrolyte with the weakly basic anion exchange resin having amino groups.

Next, a method for producing the nonaqueous electrolyte according to the present invention will be described.
The method for producing a non-aqueous electrolyte solution according to the present invention includes an acid adsorption step of passing an alkali metal salt electrolyte-containing solution in which an alkali metal salt electrolyte is dispersed in a carbonate ester through an ion exchange section containing a weakly basic anion exchange resin to obtain a non-aqueous electrolyte solution, the weakly basic anion exchange resin having a styrene-based resin base, a tertiary amino group as a weakly basic anion exchange group, and a total ion exchange capacity of 0.1 to 3.0 eq/L-R before treatment with the alkali metal salt electrolyte-containing solution.

The method for producing a non-aqueous electrolyte according to the present invention essentially produces a non-aqueous electrolyte using the production apparatus according to the present invention, and therefore the details of the production method are the same as those described above for the mode of use of the production apparatus according to the present invention.

According to the present invention, by adopting a weakly basic anion exchange resin contained in the ion exchange section that has a styrene-based resin as a base, has tertiary amino groups as weakly basic anion exchange groups, and has a total ion exchange capacity within the above range before treatment with an alkali metal salt electrolyte-containing liquid, it is possible to provide a method for producing a nonaqueous electrolyte that can be easily purified while effectively suppressing the degeneration of the tertiary amino groups, which are weakly basic anion exchange groups, into quaternary ammonium groups when acidic impurities such as hydrofluoric acid contained in the nonaqueous electrolyte are adsorbed and purified by the weakly basic anion exchange resin having tertiary amino groups.

Next, the present invention will be explained in more detail with reference to examples, but these are merely illustrative and do not limit the present invention.

Example 1
An electrolyte solution was prepared using an apparatus for producing an electrolyte solution for lithium ion batteries, which is the nonaqueous electrolyte solution producing apparatus 1 shown in FIG.
That is, first, as shown in FIG. 2, a column packed with a weakly basic anion exchange resin having a styrene-divinylbenzene base and a dimethylamino group as a weakly basic anion exchange group was prepared as an ion exchange unit 2 constituting an apparatus for producing a nonaqueous electrolyte (apparatus for producing an electrolyte for a lithium ion battery) 1.
Next, an electrolyte solution S, in which _LiPF6 was dissolved in a mixed solvent of ethylene carbonate and dimethyl carbonate in a volume ratio of 1:1, was passed through the column at a flow rate of 10 h ^-1 for 15 days using a pump P, and the electrolyte solution after passing through was stored in a tank T.
The total ion exchange capacity of the weakly basic anion exchange resin was measured before and after the above-mentioned liquid passing through it by the following method. The results are shown in Table 1.

<Method for measuring total ion exchange capacity>
After the anion exchange resin is completely converted to the chloride ion form with hydrochloric acid, excess hydrochloric acid is washed away with ethanol, and the amount of chloride ions that flow out when ammonia water is passed through is taken as the amino group exchange capacity, and the amount of chloride ions that flow out when sodium nitrate solution is then passed through is taken as the neutral salt decomposition capacity. The sum of the amino group exchange capacity and the neutral salt decomposition capacity is taken as the total ion exchange capacity.

The total ion exchange capacity indicates the amount of all ion exchange groups (the total amount of primary amino groups to tertiary amino groups and quaternary ammonium groups), and the neutral salt decomposition capacity indicates the amount of quaternary ammonium groups.
In Table 1, the neutral salt decomposition capacity and amino group exchange capacity before and after the electrolyte treatment are also shown.
Table 1 also shows the proportion of quaternary ammonium groups in the total amount of functional groups calculated according to the following formula.
Proportion (%) of quaternary ammonium groups in the total amount of functional groups=(neutral salt decomposition capacity (eq/L−R)/total ion exchange capacity (eq/L−R))×100

(Examples 2 to 4)
The apparatuses 1 for producing electrolytes for lithium ion batteries were each constructed in the same manner as in Example 1, except that the weakly basic anion exchange resin packed in the column constituting the ion exchange unit 2 was a weakly basic anion exchange resin based on styrene-divinylbenzene and having a dimethylamino group as a weakly basic anion exchange group, and had a total ion exchange capacity shown in Table 1.
Next, in the same manner as in Example 1, an electrolyte solution S, prepared by dissolving LiPF ₆ at 1 mol/L in a mixed solvent of ethylene carbonate and dimethyl carbonate in a volume ratio of 1:1, was passed through the column at a flow rate of 10 h ^-1 for 15 days using a pump P, and the electrolyte solution after passing through was stored in a tank T.
The total ion exchange capacity of the weakly basic anion exchange resin before and after the above-mentioned liquid passing was measured in the same manner as in Example 1. The results are shown in Table 1.
In Table 1, the neutral salt decomposition capacity, amino group exchange capacity, and the proportion of quaternary ammonium groups in the total amount of functional groups before and after the electrolyte treatment are also shown, as in Example 1.

(Comparative Example 1)
The weakly basic anion exchange resin was prepared in the same manner as in Example 1, except that the weakly basic anion exchange resin used was one having an acrylic resin as a base and a dimethylamino group as a weakly basic anion exchange group. The electrolyte S was passed through a column packed with the weakly basic anion exchange resin, and the total ion exchange capacity and neutral salt decomposition capacity of the weakly basic anion exchange resin were measured before and after passing the electrolyte S through the column.
The results are shown in Table 1.

From Table 1, it can be seen that in Examples 1 to 4, the removal of acidic impurities from a lithium-based electrolyte-containing solution in which a lithium-based electrolyte is dispersed in a carbonate ester is carried out by using a resin having a styrene-based resin base, a tertiary amino group as a weakly basic anion exchange group, and an amino group exchange capacity calculated by the above formula within the above range. This makes it possible to easily purify acidic impurities such as hydrofluoric acid contained in a lithium-ion battery electrolyte by adsorption with a weakly basic anion exchange resin having a tertiary amino group while effectively suppressing the degeneration of the tertiary amino group, which is a weakly basic anion exchange group, into a quaternary ammonium group.

On the other hand, Table 1 shows that in Comparative Example 1, the treatment to remove acidic impurities from the lithium-based electrolyte-containing solution in which the lithium-based electrolyte is dispersed in the carbonate ester is not performed using the specific weakly basic anion exchange resin, making it difficult to suppress the modification of tertiary amino groups to quaternary ammonium groups (quaternization reaction).

The present invention provides a nonaqueous electrolyte manufacturing apparatus that can easily purify nonaqueous electrolytes by adsorbing acidic impurities such as hydrofluoric acid contained in the nonaqueous electrolyte with a weakly basic anion exchange resin having amino groups while effectively suppressing the degeneration of the weakly basic anion exchange groups, tertiary amino groups, into quaternary ammonium groups, and can also provide a method for manufacturing nonaqueous electrolytes.

1. Non-aqueous electrolyte manufacturing equipment 2. Acid absorption equipment

Claims (6)

an ion exchange section containing a weakly basic anion exchange resin for passing an alkali metal salt electrolyte-containing liquid in which an alkali metal salt electrolyte capable of decomposing into a carbonate ester to generate an acid is dissolved, to obtain a non-aqueous electrolyte;
The weakly basic anion exchange resin has a styrene-based resin as a base, a tertiary amino group as a weakly basic anion exchange group, and a total ion exchange capacity of 0.1 to 3.0 eq/L-R before treatment with an alkali metal salt electrolyte-containing liquid. The non-aqueous electrolyte manufacturing apparatus according to claim 1, wherein the styrene-based resin is a styrene-divinylbenzene copolymer. The nonaqueous electrolyte manufacturing apparatus according to claim 1 or 2, wherein the nonaqueous electrolyte is an electrolyte for a lithium ion battery. A method for producing a non-aqueous electrolyte solution, comprising the steps of:
an acid adsorption step of passing an alkali metal salt electrolyte-containing solution, in which an alkali metal salt electrolyte capable of being decomposed into a carbonate ester to generate an acid , through an ion exchange unit containing a weakly basic anion exchange resin to obtain a non-aqueous electrolyte;
The weakly basic anion exchange resin has a styrene-based resin as a base, a tertiary amino group as a weakly basic anion exchange group, and a total ion exchange capacity before treatment with an alkali metal salt electrolyte-containing liquid of 0.1 to 3.0 eq/L-R. The method for producing a non-aqueous electrolyte according to claim 4, wherein the styrene-based resin is a styrene-divinylbenzene copolymer. The method for producing a non-aqueous electrolyte according to claim 4 or 5, wherein the non-aqueous electrolyte is an electrolyte for a lithium ion battery.

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