KR20160050555A - Manufacturing method of quaternary ammonium salt and electric double layer capacitor using the quaternary ammonium salt manufactured by the method - Google Patents

Abstract

The present invention relates to a method of preparing a quaternary ammonium salt and an electrical double layer capacitor using the quaternary ammonium salt prepared by the same, the method comprising the steps of: adding 1-methyl pyrrolidine and methyl iodide to a first solvent and conduct reaction thereof; generating 1,1-dimethylpyrrolidinium iodide by the reaction; distilling the resultant products under reduced pressure and then adding a second solvent to the same to precipitate 1,1-dimethylpyrrolidinium iodide; selectively separating the precipitated 1,1-dimethylpyrrolidinium iodide; adding the selectively separated 1,1-dimethylpyrrolidinium iodide and tetrafluoroboric acid to a third solvent and conduct reaction thereof; distilling the resultant products under reduced pressure to obtain reduced pressure concentrate; adding a fourth solvent to the reduced pressure concentrate and then stirring the mixture to precipitate P11BF4; and selectively separating the precipitated P11BF4.

Description

[0001] The present invention relates to a quaternary ammonium salt and an electric double layer capacitor using the quaternary ammonium salt,

The present invention relates to a process for producing quaternary ammonium salts and an electric double layer capacitor using the quaternary ammonium salt prepared thereby. More particularly, the present invention relates to a process for producing a quaternary ammonium salt which can be used as an electrolyte of an electric double layer capacitor and has an excellent output capacity. To an electric double layer capacitor using the quaternary quaternary ammonium salt.

Generally, an electric double layer capacitor (EDLC) is also referred to as a super-capacitor or an ultra-capacitor, and it is called an electric double layer capacitor (EDLC) (Electric double layer) is generated, and the deterioration due to the repetition of the charging / discharging operation is very small, so that the device is not required to be repaired. Accordingly, electric double layer capacitors are mainly used as an IC (integrated circuit) backup of various electric and electronic devices. Recently, the applications have been expanded to be applied to toys, solar energy storage, HEV (hybrid electric vehicle) .

The electric double layer capacitor generally comprises two electrodes of a positive electrode and a negative electrode impregnated with an electrolyte, a porous separator interposed between the two electrodes to allow ion conduction only and to prevent insulation and short circuit, A unit cell composed of a gasket for preventing leakage of electrolyte and for preventing insulation and short-circuit, and a metal cap as a conductor for packaging them. Then, one or more unit cells (normally 2 to 6 in the case of a coin type) are stacked in series and the two terminals of the positive and negative electrodes are combined.

The performance of the electric double layer capacitor is determined by the electrode active material and the electrolytic solution. Activated carbon is mainly used as an electrode active material, and the non-storage capacity based on the electrode of a commercial product is known to be about 19.3 F / cc.

Korean Patent Publication No. 10-1998-052660

The present invention provides a method for preparing quaternary ammonium salt which can be used as an electrolyte of an electric double layer capacitor and has an excellent output capacity and an electric double layer capacitor using the quaternary ammonium salt produced by the method.

(A) adding 1-methylpyrrolidine and methyl iodide to a first solvent to react them, and (b) reacting 1,1-dimethylpyrrolidinium iodide with (C) distilling the resultant of the reaction under reduced pressure, adding a second solvent to precipitate 1,1-dimethylpyrrolidinium iodide, and (d) precipitating 1,1-dimethylpyridine (E) selectively adding 1,1-dimethylpyrrolidinium iodide and tetrafluoroboric acid, which have been selectively separated, to a third solvent and reacting them; and f) step by reduced pressure distillation of the reaction product to obtain a pressure-concentrated liquid, and (g) step that it is stirred and after adding a fourth solvent to the pressure sensitive concentrate to precipitate the P ₁₁ BF _4, optionally separated from the precipitated P ₁₁ BF ₄ ≪ / RTI > a quaternary ammonium salt.

The 1-methylpyrrolidine and the methyl iodide are preferably added in a molar ratio of 1: 1-3.

The first solvent may comprise acetonitrile, methanol or ethanol.

The second solvent may include acetone, n-butanol or diethyl ether.

The 1,1-dimethylpyrrolidinium iodide is preferably added in a ratio of 140 to 350 g per 100 ml of the tetrafluoroboric acid.

The third solvent may comprise acetonitrile, methanol or ethanol.

The fourth solvent may comprise n-butanol or isopropyl alcohol.

The quaternary ammonium salt may be prepared by washing 1,1-dimethylpyrrolidinium iodide selectively separated before step (d) with acetone to remove unreacted materials after step (d) ) Step, followed by drying in a vacuum dryer to obtain P ₁₁ BF ₄ as a white solid.

The method for preparing quaternary ammonium salt may further comprise the steps of: (g) after step (g), (h) selectively removing P ₁₁ BF ₄ in a fifth solvent, and then allowing it to adsorb hydrogen iodide by allowing it to remain in a mixture of activated carbon and aluminum oxide (I) obtaining a transparent filtrate by vacuum filtration of a solution from which hydrogen iodide has been removed, and (j) distilling the filtrate under reduced pressure, adding a sixth solvent to the concentrated solution to precipitate P ₁₁ BF ₄ Followed by filtration under reduced pressure to selectively separate the precipitated P ₁₁ BF ₄ .

In the step (j), it is preferable to remove the by-product using n-butanol during the filtration under reduced pressure.

The fifth solvent may include acetonitrile, methanol or ethanol.

The sixth solvent may include n-butanol or isopropyl alcohol.

Further, the present invention is characterized in that a positive electrode and a negative electrode are disposed so as to be spaced apart from each other, and a separation membrane for preventing the short circuit between the positive electrode and the negative electrode is disposed between the positive electrode and the negative electrode, And the electrolytic solution contains a quaternary ammonium salt prepared by the above-described method.

The quaternary ammonium salt of the present invention can be used as an electrolyte for electric double layer capacitors and has excellent output capacity.

1 is a graph showing the results of ¹ H-NMR analysis of a quaternary ammonium salt prepared according to Experimental Example 1. FIG.
FIG. 2 shows charge and discharge curves of the capacitor manufactured according to Experimental Example 2 and Comparative Example.
3 is a graph showing changes in discharge capacity in experiments in which capacitors manufactured according to Experimental Example 2 and Comparative Example were charged and discharged at different current densities, respectively.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, it should be understood that the following embodiments are provided so that those skilled in the art will be able to fully understand the present invention, and that various modifications may be made without departing from the scope of the present invention. It is not.

The method for preparing a quaternary ammonium salt according to a preferred embodiment of the present invention comprises the steps of: (a) adding 1-methylpyrrolidine and methyl iodide to a first solvent to react; and (b) Dimethylpyrrolidinium iodide; (c) subjecting the result of the reaction to reduced pressure distillation, followed by addition of a second solvent to precipitate 1,1-dimethylpyrrolidinium iodide; and (d) selectively separating the precipitated 1,1-dimethylpyrrolidinium iodide, and (e) separating the selectively separated 1,1-dimethylpyrrolidinium iodide and tetrafluoroboric acid (B) adding a solvent to the reaction mixture to obtain a reduced pressure concentrate; and (f) subjecting the reaction product to a vacuum distillation to obtain a vacuum concentrate; and (g) adding a fourth solvent to the vacuum concentrate and stirring to precipitate P ₁₁ BF ₄ , and a step that by selectively removing the P ₁₁ BF ₄ .

The 1-methylpyrrolidine and the methyl iodide are preferably added in a molar ratio of 1: 1-3.

The first solvent may comprise acetonitrile, methanol or ethanol.

The second solvent may include acetone, n-butanol or diethyl ether.

The 1,1-dimethylpyrrolidinium iodide is preferably added in a ratio of 140 to 350 g per 100 ml of the tetrafluoroboric acid.

The third solvent may comprise acetonitrile, methanol or ethanol.

The fourth solvent may comprise n-butanol or isopropyl alcohol.

The quaternary ammonium salt may be prepared by washing 1,1-dimethylpyrrolidinium iodide selectively separated before step (d) with acetone to remove unreacted materials after step (d) ) Step, followed by drying in a vacuum dryer to obtain P ₁₁ BF ₄ as a white solid.

The method for preparing quaternary ammonium salt may further comprise the steps of: (g) after step (g), (h) selectively removing P ₁₁ BF ₄ in a fifth solvent, and then allowing it to adsorb hydrogen iodide by allowing it to remain in a mixture of activated carbon and aluminum oxide (I) obtaining a transparent filtrate by vacuum filtration of a solution from which hydrogen iodide has been removed, and (j) distilling the filtrate under reduced pressure, adding a sixth solvent to the concentrated solution to precipitate P ₁₁ BF ₄ Followed by filtration under reduced pressure to selectively separate the precipitated P ₁₁ BF ₄ .

In the step (j), it is preferable to remove the by-product using n-butanol during the filtration under reduced pressure.

The fifth solvent may include acetonitrile, methanol or ethanol.

The sixth solvent may include n-butanol or isopropyl alcohol.

In an electric double layer capacitor according to a preferred embodiment of the present invention, an anode and a cathode are disposed so as to be spaced apart from each other, a separation membrane for preventing short-circuit between the anode and the cathode is disposed between the anode and the cathode, The separator and the negative electrode are impregnated with an electrolytic solution, and the electrolytic solution includes a quaternary ammonium salt prepared by the method described above.

Hereinafter, a method for producing a quaternary ammonium salt according to a preferred embodiment of the present invention and an electric double layer capacitor using the quaternary ammonium salt produced by the method will be described in more detail. The quaternary ammonium salt is a ₁₁ P BF _4.

For the synthesis of quaternary ammonium salt P ₁₁ BF ₄ , 1-methylpyrrolidine and methyl iodide are added to the first solvent.

The 1-methylpyrrolidine and the methyl iodide are preferably added in a molar ratio of 1: 1-3.

The first solvent may be acetonitrile, methanol or ethanol.

The reaction is preferably carried out at room temperature of about 5 to 30 DEG C for 10 minutes to 48 hours while stirring. The stirring is preferably performed at a speed of about 10 to 500 rpm.

1,1-Dimethylpyrrolidinium iodide is produced by the reaction, and the 1,1-dimethylpyrrolidinium iodide exists in a form dissolved in the first solvent.

After the reaction product is distilled off under reduced pressure, a second solvent is added to precipitate 1,1-dimethylpyrrolidinium iodide. The second solvent may be acetone, n-butanol or diethyl ether.

The precipitated 1,1-dimethylpyrrolidinium iodide is selectively removed. Selective separation of 1,1-dimethylpyrrolidinium iodide can be performed by reduced-pressure filtration. The selectively isolated 1,1-dimethylpyrrolidinium iodide is preferably washed with acetone to remove unreacted materials.

After selectively separating and drying, the intermediate product, 1,1-dimethylpyrrolidinium iodide, can be obtained. The drying is preferably performed in a vacuum dryer at a temperature of about 40 to 180 DEG C for 10 minutes to 24 hours.

Scheme 1 below shows the reaction scheme for obtaining the intermediate product 1,1-dimethylpyrrolidinium iodide.

The intermediate product, 1,1-dimethylpyrrolidinium iodide, and tetrafluoroboric acid (HBF ₄ ) are added to the third solvent and allowed to react. Through this reaction, the exchange of anions of I ^- and BF ₄ ^- occurs and P ₁₁ BF ₄ is produced.

The 1,1-dimethylpyrrolidinium iodide is preferably added in a ratio of 140 to 350 g per 100 ml of the tetrafluoroboric acid.

The third solvent may be acetonitrile, methanol or ethanol.

Scheme 2 below shows the reaction scheme for obtaining the final product P ₁₁ BF ₄ quaternary ammonium salt.

[Reaction Scheme 2]

The reaction is preferably carried out at room temperature of about 5 to 30 DEG C for 10 minutes to 24 hours while stirring. The stirring is preferably performed at a speed of about 10 to 500 rpm.

The reaction product is distilled under reduced pressure to obtain a brown solution, which is a reduced pressure concentrate. Products other than P ₁₁ BF ₄ can be hydrogen iodide, iodine, hydrogen, and the like.

A fourth solvent is added to the reduced pressure concentrate, which is then stirred to precipitate P ₁₁ BF ₄ , and the precipitated P ₁₁ BF ₄ is selectively removed. Selective separation of ₁₁ P BF ₄ may use the filtered under reduced pressure. The fourth solvent may be n-butanol or isopropyl alcohol.

The following purification process can be further performed on the selectively separated P ₁₁ BF ₄ .

In order to remove impurities such as hydrogen iodide in the separated P ₁₁ BF ₄ , it is dissolved in a fifth solvent, and then it is left in a mixture of activated carbon and aluminum oxide to adsorb and remove hydrogen iodide. The fifth solvent may be acetonitrile, methanol or ethanol.

A solution in which hydrogen iodide and the like are removed is filtered under reduced pressure to obtain a transparent filtrate.

And then added to the sixth solvent to the concentrated solution by distillation under reduced pressure of the filtrate to precipitate a P ₁₁ BF _4, recall selectively separating the precipitate was filtered under reduced pressure to P ₁₁ BF _4. The sixth solvent may be n-butanol or isopropyl alcohol. It is preferable to remove n-butanol as a washing solution to remove a small amount of by-products during the filtration under reduced pressure.

P ₁₁ BF ₄ is dissolved in a fifth solvent, and then the solution is allowed to stand in a mixture of activated carbon and aluminum oxide to adsorb and remove hydrogen iodide, etc., and a solution in which hydrogen iodide and the like are removed is filtered under reduced pressure to obtain a clear filtrate Step and distilling the filtrate under reduced pressure, adding a sixth solvent to the concentrated solution, precipitating P ₁₁ BF _4, and filtering the precipitated P ₁₁ BF ₄ selectively at least twice to obtain P ₁₁ BF 4 ₄ is preferably purified.

When the purified product is dried, a white solid P ₁₁ BF ₄ can be obtained. The drying is preferably performed in a vacuum dryer at a temperature of about 40 to 180 DEG C for 10 minutes to 24 hours.

The quaternary ammonium salt thus prepared can be used as an electrolyte of an electric double layer capacitor. Quaternary ammonium salts may be usefully applied to coin-type electric double layer capacitors, wound electric double layer capacitors, and the like.

In an electric double layer capacitor according to a preferred embodiment of the present invention, an anode and a cathode are disposed so as to be spaced apart from each other, a separation membrane for preventing short-circuit between the anode and the cathode is disposed between the anode and the cathode, The separator and the negative electrode are impregnated with an electrolytic solution, and the electrolytic solution is composed of an electrolyte and a solvent, and the electrolyte includes a quaternary ammonium salt. Since the structure of the electric double layer capacitor is generally known, detailed description thereof will be omitted here.

It is preferable that the molar concentration of the electrolyte is in the range of 0.1 to 2M.

The solvent may be selected from the group consisting of ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, At least one selected from the group consisting of methanol, ethanol, isopropanol, ethanol, isopropanol, ethanol, isopropanol, isopropanol, ≪ / RTI >

The separator may be a battery such as a polyethylene nonwoven fabric, a polypropylene nonwoven fabric, a polyester nonwoven fabric, a polyacrylonitrile porous separator, a poly (vinylidene fluoride) hexafluoropropane copolymer porous separator, a cellulose porous separator, a kraft paper or a rayon fiber, And is not particularly limited as long as it is a membrane commonly used in the field.

The positive electrode and the negative electrode may be formed in the form of an electrode by pressing an electrode composition formed by mixing active carbon, a binder, a conductive material, and a solvent, which is an electrode active material, or by coating the electrode composition with a metal foil to form an electrode, The composition for electrodes can be formed by pressing the composition with a roller to form a sheet, attaching it to a metal foil to form an electrode, and drying the resultant product at a temperature of 100 ° C to 350 ° C.

The binder may be selected from the group consisting of polytetrafluoroethylene (PTFE), polyvinylidenefluoride (PVdF), carboxymethylcellulose (CMC), polyvinyl alcohol (PVA), polyvinyl butyral vinyl butyral (PVB), poly-N-vinylpyrrolidone (PVP), styrene butadiene rubber (SBR), and the like.

The conductive material is not particularly limited as long as it is an electron conductive material which does not cause a chemical change. Examples of the conductive material include natural graphite, artificial graphite, carbon black, acetylene black, Ketjen black, Super-P black, carbon fiber, , Metal powder such as aluminum and silver, or metal fiber.

The solvent for forming the anode and the cathode may be an organic solvent such as ethanol (EtOH), acetone, isopropyl alcohol, methyl pyrrolidone (NMP), propylene glycol, or water.

Hereinafter, experimental examples according to the present invention will be specifically shown, and the present invention is not limited by the following experimental examples.

<Experimental Example 1>

To synthesize P ₁₁ BF ₄ , 21.72 ml of 1-Methylpyrrolidine (Tokyo Chemical Industry Co., 98%) was added to 300 ml of acetonitrile (Daejung Chem. Co., 99.5% And 15.4 ml of methyl iodide (Junsei Chemical Co., 97%) was added while stirring, followed by reaction at room temperature for 12 hours. At this time, 1-methylpyrrolidine and methyl iodide were reacted at a molar ratio of 1: 2. The agitation was carried out at a speed of about 300 rpm.

The product of the reaction is 1,1-dimethylpyrrolidinium iodide in the form of being dissolved in acetonitrile. The solution is distilled under reduced pressure, then dissolved in acetone (Acetone) (Daejung Chem. Co ., 99.5%) was added to precipitate 1,1-dimethylpyrrolidinium iodide. 1,1-dimethylpyrrolidinium iodide precipitated by filtration under reduced pressure was selectively separated, and then washed with acetone to remove unreacted materials.

The product was dried in a vacuum dryer at 40 캜 for 2 hours to obtain 34.6 g of 1,1-dimethylpyrrolidinium iodide.

35 g of synthesized 1,1-dimethylpyrrolidinium iodide was added to 250 ml of acetonitrile together with 23 ml of tetrafluoroboric acid (Alfa Aesar, 50% in water), stirred for 1 hour at room temperature Lt; / RTI &gt; Through this reaction, the exchange of anions of I ^- and BF ₄ ^- occurs and P ₁₁ BF ₄ is produced. The agitation was carried out at a speed of about 300 rpm.

The reaction product was subjected to vacuum distillation to obtain a brown solution, which was a vacuum concentrated solution. The products other than P ₁₁ BF ₄ may be hydrogen iodide, iodine, hydrogen, and the like. N-butanol (Daejung Chem. Co., 99%) was added to the concentrated solution, and P ₁₁ BF ₄ was precipitated with stirring to selectively precipitate P ₁₁ BF ₄ precipitated by filtration under reduced pressure .

To remove hydrogen iodide and the like in the separated P ₁₁ BF ₄ , it was dissolved in acetonitrile, and then a mixture of activated carbon (Samchun pure Chem. Co.) And aluminum oxide (Daejung Chem. And left for a minute to adsorb and remove hydrogen iodide and the like.

A solution in which hydrogen iodide and the like were removed was filtered under reduced pressure to obtain a clear filtrate.

To the concentrated solution obtained by distilling the filtrate under reduced pressure, 300 ml of n-butanol was added to precipitate P ₁₁ BF _4, and the precipitated P ₁₁ BF ₄ was selectively separated by vacuum filtration. During the filtration under reduced pressure, n-butanol was used as a washing solution to remove a small amount of by-products.

P ₁₁ BF ₄ is dissolved in acetonitrile, and then the solution is left in a mixture of activated carbon and aluminum oxide to adsorb and remove hydrogen iodide, etc., and a solution in which hydrogen iodide and the like are removed is filtered under reduced pressure to obtain a clear filtrate Step and distillation of the filtrate under reduced pressure, n-butanol was added to the concentrated solution to precipitate P ₁₁ BF ₄ , followed by filtration under reduced pressure to selectively separate the precipitated P ₁₁ BF _4. This step was repeated two more times to obtain P ₁₁ BF ₄ was purified.

Thereafter, it was dried in a vacuum dryer at 40 캜 for 24 hours to obtain 5.3 g (0.028 mol) of P ₁₁ BF _{4 as} a white solid.

A small amount of P ₁₁ BF ₄ was dissolved in distilled water, and 0.1 M silver nitrate was added to confirm the formation of the precipitate to confirm whether or not the other products (impurities, by-products), hydrogen iodide, were detected. After that, the structure was confirmed by ¹ H-NMR analysis of the product in the state where no precipitate was formed. ¹ H-NMR analysis was carried out by dissolving P ₁₁ BF ₄ in 1 ml of dimethyl sulfoxide-d6 (Cambridge Isotope Laboratories Inc.) and then using an NMR spectrometer (Avance-250, Bruker).

^The results of ¹ H-NMR analysis are as follows. ^{1 H-NMR (250MHz DMSO)} : δ 2.08 (4H, quintet, -CH 2), 3.06 (6H, s, N-CH 3), 3.45 (4H, t, N-CH 2)

<Experimental Example 2>

A coin type capacitor was prepared using the quaternary ammonium salt prepared according to Experimental Example 1 as an electrolytic solution.

1. Preparation of electrolyte

To prepare the electrolytic solution, the weight of the quaternary ammonium salt equivalent to 10 ml of 1.0M was weighed. The weighed quaternary ammonium salt was placed in a 10 ml volumetric flask and acetonitrile (Sigma Aldrich, 99.8%) was added to the indicated line to prepare an electrolytic solution.

Table 1 below shows the molecular weights and weights of quaternary ammonium salts used as electrolytes.

Quaternary ammonium salt Molecular weight (g / mol) Weight (g)
(1.0M, based on 10 mL) P ₁₁ BF ₄ 190.98 1.9098

2. Electrode Manufacturing

81 wt% of activated carbon (MSP-20, Kansai Cokes, specific surface area 2100 m ² g ¹ ), carbon black (Super P black, Timcal) 12.8 wt%, styrene butadiene rubber 4.2 wt% of SBR (BM-400B, Zeon) and 2 wt% of carboxymethylcellulose (CMC) (Sigma Aldrich) were mixed and stirred to prepare an electrode slurry.

Using a doctor blade, an electrode slurry was coated on an aluminum foil (thickness 22 mu m) and vacuum-dried in a vacuum oven at 40 DEG C for 12 hours to obtain an activated carbon electrode plate (thickness 208 mu m).

In order to manufacture a coin cell type capacitor, the activated carbon electrode plate was formed into a circular activated carbon electrode having a diameter of 14 mm.

3. Cell production

The coin cell was assembled as a full cell using CR2032 type. The assembly procedure is as follows.

(Diameter: 15 mm, thickness: 1.4 mm), a coin cell cap, a coin cell cup, an activated carbon electrode, a separator (cellulose, diameter 19 mm, thickness 40 μm) Laminated and assembled. During the assembly process, 100 μl was injected between the activated carbon electrode and the separator. The laminated coin cell was compressed by a sealing device to complete the assembly.

4. Analysis Method

The output experiment was performed by injecting a current density of 0.1Ag ^-1 to 5.0Ag ^-1 at a voltage range of 0V to 3.0V.

The discharge was initiated when the current reached 10% of the current density. The discharge was initiated when the current reached 10% of the current density.

The discharge is terminated when the voltage reaches 0.001V, and charging of the next stage begins without a dwell period.

Charging and discharging were carried out for 5 cycles at each current density, and the output capacity obtained from the current density was taken as an average value of 5 cycles.

<Comparative Example>

To prepare the electrolytic solution, the weight of tetraethylammonium tetrafluoroborate (TEA BF4) corresponding to 10 ml of 1.0M was weighed with a balance. The weighed TEA BF ₄ was placed in a 10 ml volumetric flask and acetonitrile (Sigma Aldrich, 99.8%) was added to the indicated line to prepare an electrolytic solution.

A coin-type supercapacitor pull cell was fabricated in the same manner as in Experimental Example 2 by using the electrolyte thus prepared.

FIG. 2 shows charge and discharge curves of the capacitor manufactured according to Experimental Example 2 and Comparative Example. 2 (a) shows the case of using an electrolyte solution containing TEA BF ₄ , and (b) shows the case of using an electrolytic solution containing P ₁₁ BF ₄ .

Referring to FIG. 2, the time vs. voltage of the charge and discharge tests at a current density of 0.1 A g ^-1 is shown. The graph of Figure 3 shows the universal charging and discharging aspect of the capacitor.

3 is a graph showing changes in discharge capacity in experiments in which capacitors manufactured according to Experimental Example 2 and Comparative Example were charged and discharged at different current densities, respectively. FIG. 3 (a) shows the case of using an electrolyte solution containing TEA BF _4, and FIG. 3 (b) shows the case of using an electrolyte containing P ₁₁ BF ₄ .

Referring to FIG. 3, the discharge capacity was dominated by P ₁₁ BF ₄ having a small cation radius.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, This is possible.

Claims (13)

(a) adding 1-methylpyrrolidine and methyl iodide to a first solvent to react;
(b) producing 1,1-dimethylpyrrolidinium iodide by the reaction;
(c) distilling the resultant of the reaction under reduced pressure, and then adding a second solvent to precipitate 1,1-dimethylpyrrolidinium iodide;
(d) selectively separating the precipitated 1,1-dimethylpyrrolidinium iodide;
(e) adding selectively separated 1,1-dimethylpyrrolidinium iodide and tetrafluoroboric acid to a third solvent to react;
(f) subjecting the result of the reaction to vacuum distillation to obtain a reduced pressure concentrate; And
(g) method for producing a quaternary ammonium salt characterized in that it comprises the steps that to precipitate the ₁₁ P claim 4 BF ₄ was added with stirring and the solvent to the concentrated solution under reduced pressure, selectively separating the precipitated P ₁₁ BF _4.
The process for producing a quaternary ammonium salt according to claim 1, wherein the 1-methylpyrrolidine and the methyl iodide are added in a molar ratio of 1: 1 to 3: 1.
The method of claim 1, wherein the first solvent comprises acetonitrile, methanol or ethanol.
The method of claim 1, wherein the second solvent comprises acetone, n-butanol or diethyl ether.
The method according to claim 1, wherein the 1,1-dimethylpyrrolidinium iodide is added in an amount of 140 to 350 g per 100 ml of the tetrafluoroboric acid.
The method of claim 1, wherein the third solvent comprises acetonitrile, methanol or ethanol.
The method of claim 1, wherein the fourth solvent comprises n-butanol or isopropyl alcohol.
The method of claim 1, further comprising, after step (d), washing the 1,1-dimethylpyrrolidinium iodide selectively separated before step (e) with acetone to remove unreacted material. And
And drying in a vacuum dryer after step (g) to obtain P ₁₁ BF ₄ as a white solid.
2. The method of claim 1, wherein after step (g)
(h) dissolving selectively separated P ₁₁ BF ₄ in a fifth solvent, and allowing to stand in a mixture of activated carbon and aluminum oxide to adsorb and remove hydrogen iodide;
(i) filtering the solution from which hydrogen iodide has been removed under reduced pressure to obtain a transparent filtrate; And
(j) further comprising the step of distilling the filtrate under reduced pressure, adding a sixth solvent to the concentrated solution to precipitate P ₁₁ BF _4, and then filtering the precipitated P ₁₁ BF ₄ by selective filtration &Lt; / RTI &gt;
The method according to claim 9, wherein the by-product is removed using n-butanol during the vacuum filtration in step (j).
10. The method of claim 9, wherein the fifth solvent comprises acetonitrile, methanol or ethanol.
10. The method of claim 9, wherein the sixth solvent comprises n-butanol or isopropyl alcohol.
The positive electrode and the negative electrode are arranged so as to be spaced apart from each other,
A separation membrane for preventing a short circuit between the anode and the cathode is disposed between the anode and the cathode,
Wherein the anode, the separator, and the cathode are impregnated with an electrolytic solution,
Wherein the electrolytic solution comprises the quaternary ammonium salt prepared by the process of claim 1. &lt; Desc / Clms Page number 19 &gt;

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