JP2019169700A - Electrolyte solution for electrochemical device, and electrochemical device - Google Patents

Abstract

To provide an electrolyte solution for an electrochemical device, which can increase the high-temperature reliability of an electrochemical device, and an electrochemical device containing the electrolyte solution.SOLUTION: An electrolyte solution for an electrochemical device comprises: an electrolyte solution containing a solvent of a cyclic carbonate and as an electrolyte, 0.8 mol/L or more and 1.6 mol/L or less of LiPF; and a chain carbonate of which the addition amount to the electrolyte solution is equal to or more than 0.1 wt% and less than 10.0 wt%.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electrolytic solution for an electrochemical device and an electrochemical device.

  Electrochemical devices such as electric double layer capacitors and lithium ion capacitors using a non-aqueous electrolyte can increase the withstand voltage because of the high electrolysis voltage of the solvent, and can store a large amount of energy.

In recent years, electrochemical devices are required to ensure reliability at high temperatures. For the high-temperature reliability, PF ₆ is an electrolyte ^- decomposition products such as hydrogen fluoride anions is decomposed such occurs, the like which the electrolytic solution is reduced and decomposed at the anode vicinity to form a high-resistance film, It is believed that the cell characteristics are deteriorating.

In order to solve the above problem, for example, Patent Document 1 discloses lithium ions using an electrolytic solution in which lithium tetrafluoroborate (LiBF ₄ ) and lithium bis (pentafluoroethylsulfonyl) imide (LiBETI) are mixed at a certain ratio. A battery is disclosed. Patent Document 2 discloses a lithium ion battery using an electrolytic solution in which LiBF ₄ is partially added to lithium hexafluorophosphate (LiPF ₆ ) in order to improve high-temperature storage characteristics. In Patent Document 3, by adding a methylene bissulfonate derivative to an electrolytic solution using a mixed solvent of ethylene carbonate and ethyl methyl carbonate, the cycle characteristics of a lithium ion battery and the characteristics after a short-term high-temperature holding test can be improved. Proposed electrolyte.

JP 2001-236990 A JP 2003-346898 A International Publication No. 2012/017999

When an electrolytic solution in which LiBF ₄ and LiBETI are mixed at a certain ratio as in Patent Document 1 is used, an electrolytic solution using LiPF ₆ as an electrolyte is obtained from the high heat resistance of the electrolyte and the high electrical conductivity of LiBETI. Although the stability of the electrolytic solution at a high temperature is improved, LiBETI corrodes the current collector foil (aluminum) when the positive electrode potential is around 4 V (vs Li / Li ⁺ ), so that there is a problem in long-term reliability.

In Patent Document 2, it is disclosed to suppress the deterioration of the battery after high temperature storage using an electrolytic solution obtained by mixing a part LiBF ₄ to LiPF _6, LiPF ₆ at a high temperature (60 ° C.) is too pyrolysis Even if it is effective, the thermal decomposition of LiPF ₆ cannot be ignored in an environment of 85 ° C., and the reliability of the battery cannot be improved.

  In Patent Document 3, when a high temperature is maintained for a long period of time, problems such as further formation of a coating on the negative electrode surface and decomposition of the electrolytic solution may occur.

  This invention is made | formed in view of the said subject, and aims at providing the electrolyte solution for electrochemical devices which can improve the high temperature reliability of an electrochemical device, and an electrochemical device provided with the same. .

The electrolytic solution for electrochemical devices according to the present invention includes an electrolytic solution in which 0.8 mol / L or more and 1.6 mol / L or less of LiPF ₆ is contained as an electrolyte in a cyclic carbonate solvent, and an addition amount to the electrolytic solution is 0.1. 1% by weight or more and less than 10.0% by weight of chain carbonate.

  In the electrochemical device electrolyte, the additive amount of the electrolyte solution is 0.1 wt% or more and 5.0 wt% or less, and at least one of a carbonate ester, a sulfonate ester, and an oxalate complex salt of lithium is further added. May be included.

  In the electrolytic solution for electrochemical devices, the carbonate ester may be at least one of vinylene carbonate and fluoroethylene carbonate.

  In the electrolytic solution for electrochemical devices, the sulfonic acid ester may be bis (ethanesulfonic acid) methylene.

  In the electrolytic solution for electrochemical devices, the oxalato complex salt may be at least one of lithium bis (oxalato) borate, lithium difluorobis (oxalato) phosphate, and lithium tetrafluorooxalatophosphate.

  In the electrochemical device electrolyte, the chain carbonate may be at least one of dimethyl carbonate, ethyl methyl carbonate, and diethyl carbonate.

  An electrochemical device according to the present invention includes a power storage element in which a positive electrode and a negative electrode are stacked via a separator, and the positive electrode active material and the negative electrode active material, or the separator according to any one of the above It is impregnated with an electrolytic solution for a device.

  ADVANTAGE OF THE INVENTION According to this invention, the electrolyte solution for electrochemical devices which can improve the high temperature reliability of an electrochemical device, and an electrochemical device provided with the same can be provided.

It is an exploded view of a lithium ion capacitor. It is sectional drawing of the lamination direction of a positive electrode, a negative electrode, and a separator. It is an exploded view of a lithium ion capacitor. It is an external view of a lithium ion capacitor. It is a figure which shows a test result.

  Hereinafter, embodiments will be described with reference to the drawings.

(Embodiment)
First, a lithium ion capacitor will be described as an example of an electrochemical device. FIG. 1 is an exploded view of the lithium ion capacitor 100. As illustrated in FIG. 1, the lithium ion capacitor 100 includes a storage element 50 having a structure in which a positive electrode 10 and a negative electrode 20 are wound through a separator 30. The electricity storage element 50 has a substantially cylindrical shape. A lead terminal 41 is connected to the positive electrode 10. The lead terminal 42 is connected to the negative electrode 20.

  FIG. 2 is a cross-sectional view of the positive electrode 10, the negative electrode 20, and the separator 30 in the stacking direction. As illustrated in FIG. 2, the positive electrode 10 has a structure in which a positive electrode layer 12 is laminated on one surface of a positive electrode current collector 11. A separator 30 is stacked on the positive electrode layer 12 of the positive electrode 10. The negative electrode 20 is laminated on the separator 30. The negative electrode 20 has a structure in which a negative electrode layer 22 is laminated on the surface of the negative electrode current collector 21 on the positive electrode 10 side. A separator 30 is stacked on the negative electrode current collector 21 of the negative electrode 20. In the electric storage element 50, the stacked units of the positive electrode 10, the separator 30, the negative electrode 20, and the separator 30 are wound. The positive electrode layer 12 may be provided on both surfaces of the positive electrode current collector 11. The negative electrode layer 22 may be provided on both surfaces of the negative electrode current collector 21.

  As illustrated in FIG. 3, a lead terminal 41 and a lead terminal 42 are inserted into two through holes of a substantially cylindrical sealing rubber 60 having substantially the same diameter as the power storage element 50. The power storage element 50 is housed in a bottomed, substantially cylindrical container 70. As illustrated in FIG. 4, the sealing rubber 60 is caulked around the opening of the container 70. Thereby, the sealing property of the electrical storage element 50 is maintained. The nonaqueous electrolytic solution is sealed in the container 70 and impregnated in the active material of the positive electrode 10 and the active material of the negative electrode 20 or the separator 30.

(Positive electrode)
The positive electrode current collector 11 is a metal foil, such as an aluminum foil. This aluminum foil may be a perforated foil. The positive electrode layer 12 only needs to have a known material and structure used for an electrode layer of an electric double layer capacitor or a redox capacitor. For example, polyacene (PAS), polyaniline (PAN), activated carbon, carbon black, graphite, It contains an active material such as carbon nanotube, and also contains other components such as a conductive additive and a binder used for electrode layers such as electric double layer capacitors, as necessary.

(Negative electrode)
The negative electrode current collector 21 is a metal foil, such as a copper foil. This copper foil may be a perforated foil. The negative electrode layer 22 contains an active material such as non-graphitizable carbon, graphite, tin oxide, silicon oxide, and the like, and includes conductive assistants such as carbon black and metal powder, polytetrafluoroethylene (PTFE), and polyfluoride. Binders such as vinylidene chloride (PVDF) and styrene butadiene rubber (SBR) are also contained as required.

(Separator)
For example, the separator 30 is provided between the positive electrode 10 and the negative electrode 20, thereby preventing a short circuit due to the contact between these two electrodes. The separator 30 forms a conductive path between the electrodes by holding the nonaqueous electrolytic solution in the pores. As a material for the separator 30, for example, porous cellulose, polypropylene, polyethylene, fluorine resin, or the like can be used.

  Note that the lithium metal sheet is electrically connected to the negative electrode 20 when the storage element 50 and the non-aqueous electrolyte are sealed in the container 70. Thereby, lithium of the lithium metal sheet is dissolved in the nonaqueous electrolytic solution, and lithium ions are pre-doped in the negative electrode layer 22 of the negative electrode 20. Thereby, the potential of the negative electrode 20 becomes lower than the potential of the positive electrode 10 by, for example, about 3 V before charging.

  Further, in the present embodiment, the lithium ion capacitor 100 has a structure in which the storage element 50 having a wound structure is enclosed in the cylindrical container 70, but is not limited thereto. For example, the power storage element 50 may have a stacked structure. Further, the container 70 in this case may be a square can or the like.

(Nonaqueous electrolyte)
The nonaqueous electrolytic solution can be prepared by dissolving an electrolyte in a nonaqueous solvent and further adding an additive. First, cyclic carbonate is used as a non-aqueous solvent. The cyclic carbonate is a cyclic carbonate such as propylene carbonate (PC) or ethylene carbonate (EC). Since the cyclic carbonate has a high dielectric constant, it has a property of dissolving lithium salt well. Moreover, the non-aqueous electrolyte using cyclic carbonate as a non-aqueous solvent has high ionic conductivity. Therefore, when the cyclic carbonate is used as the non-aqueous solvent, the initial characteristics of the lithium ion capacitor 100 are improved. Further, when cyclic carbonate is used as the non-aqueous solvent, sufficient electrochemical stability during operation of the lithium ion capacitor 100 is realized after the coating is formed on the negative electrode 20.

LiPF ₆ that is a lithium salt is used as the electrolyte. Since LiPF ₆ has a high degree of dissociation among general-purpose lithium salts, it achieves good initial characteristics (capacitance and DCR) of the lithium ion capacitor 100. If the concentration of the electrolyte in the non-aqueous electrolyte (electrolyte concentration) is too high, the viscosity of the electrolyte will increase, and it will take time for the required amount of ions to be supplied to the electrode. May rise. On the other hand, if the electrolyte concentration is too low, a necessary amount of ions is not supplied to the electrode, or it takes time to be supplied, so that the initial capacity may be reduced and the initial internal resistance may be increased. Therefore, an upper limit and a lower limit are set for the electrolyte concentration. In the present embodiment, the electrolyte concentration is 0.8 mol / L or more and 1.6 mol / L or less. The electrolyte concentration is preferably 1.0 mol / L or more and 1.4 mol / L or less. In this embodiment, since LiBFTI is not used for the electrolyte, corrosion of the positive electrode 10 is suppressed.

(First additive)
As the first additive added to the non-aqueous electrolyte, a chain carbonate is used. The reason why the chain carbonate is used is to increase the capacity maintenance ratio when the lithium ion capacitor 100 is exposed to a high temperature and to reduce the internal resistance change. This is because by adding a small amount of chain carbonate to the electrolytic solution, the viscosity of the electrolytic solution is lowered, and as a result, the film forming material acts more uniformly on the negative electrode 20 to form a thinner, homogeneous and firm coating. It is thought that it is from. As the chain carbonate, dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC) or the like can be used. These may be used in combination as the first additive. If the concentration of the first additive in the non-aqueous electrolyte is too low, it is difficult to sufficiently obtain the effect of the first additive. Therefore, a lower limit is set for the concentration of the first additive in the non-aqueous electrolyte. On the other hand, if the concentration of the first additive in the nonaqueous electrolytic solution is too high, dissociation of LiPF _{6 in} the electrolytic solution is hindered, and thermal decomposition of LiPF ₆ may be promoted at a high temperature. Therefore, an upper limit is set for the concentration of the first additive in the non-aqueous electrolyte. In the present embodiment, the concentration of the first additive in the non-aqueous electrolyte is 0.1 wt% or more and less than 10.0 wt%. Note that the concentration of the first additive in the nonaqueous electrolytic solution is preferably 9.0 wt% or less, and more preferably 5.0 wt% or less. In addition, the concentration of the first additive in the non-aqueous electrolyte is preferably 0.5 wt% or more, and more preferably 1.0 wt% or more.

(Second additive)
In order to further reduce the internal resistance change when the lithium ion capacitor 100 is exposed to a high temperature, in addition to the first additive, at least one of a carbonate ester, a sulfonate ester, and a lithium oxalato complex salt is added. Two additives may be added. The second additive has a reduction potential higher than that of the non-aqueous solvent of the non-aqueous electrolyte, and acts on the negative electrode 20 to form a stable film. As the carbonate ester, vinylene carbonate (VC), fluoroethylene carbonate (FEC), or the like can be used. As the sulfonic acid ester, bis (ethanesulfonic acid) methylene (MBES) or the like can be used. Lithium oxalate complex salts include lithium bis (oxalato) borate (LiB (C ₂ O ₄ ) ₂ ), lithium difluorobis (oxalato) phosphate (LiPF ₂ (C ₂ O ₄ ) ₂ ), tetrafluorooxalatoline Lithium acid (LiPF ₄ (C ₂ O ₄ )) or the like can be used. In order to sufficiently obtain the effect of the second additive, it is preferable to provide a lower limit for the concentration of the second additive. On the other hand, if the concentration of the second additive in the non-aqueous electrolyte is too high, a thick film is formed on the negative electrode 20, so that the initial internal resistance increases and the internal resistance change may also increase. Therefore, it is preferable to set an upper limit for the concentration of the second additive in the nonaqueous electrolytic solution. In the present embodiment, the concentration of the second additive in the nonaqueous electrolytic solution is preferably 0.1 wt% or more, more preferably 0.2 wt% or more, and 0.5 wt% or more. Further preferred. Further, the concentration of the second additive in the non-aqueous electrolyte is preferably 5.0 wt% or less, more preferably 3.0 wt% or less, and further preferably 1.0 wt% or less.

In this embodiment, in a non-aqueous electrolyte solution using cyclic carbonate as a non-aqueous solvent and 0.8 mol / L or more and 1.6 mol / L or less of LiPF ₆ as an electrolyte, the amount added to the non-aqueous electrolyte solution is 0.1 wt. %, More than less than 10.0 wt% of chain carbonate, it is possible to obtain a good capacity retention ratio and sufficiently reduce the change in internal resistance even when the lithium ion capacitor 100 is exposed to a high temperature. Therefore, high temperature reliability can be improved.

  In the present embodiment, attention is focused on the electrolyte solution of a lithium ion capacitor as an electrochemical device, but the present invention is not limited thereto. For example, the nonaqueous electrolytic solution according to this embodiment can be used as an electrolytic solution for other electrochemical devices such as an electric double layer capacitor.

  According to the above embodiment, a lithium ion capacitor was manufactured and examined for characteristics.

Example 1
PAS was used as the active material of the positive electrode 10. A slurry was prepared using carboxymethyl cellulose and styrene butadiene rubber as a binder, and the prepared slurry was applied onto an aluminum foil that had been perforated to prepare a sheet. As the active material of the negative electrode 20, non-graphitizable carbon made of a phenol resin raw material was used. A slurry was prepared using carboxymethyl cellulose and styrene butadiene rubber as a binder, and the prepared slurry was applied on a copper foil having a perforated process to prepare a sheet. A cellulose-based separator 30 is sandwiched between these electrodes, the extraction terminal 41 is attached to the positive electrode current collector 11 by ultrasonic welding, the extraction terminal 42 is attached to the negative electrode current collector 21, and these are wound to obtain a polyimide adhesive. The electricity storage element 50 was fixed with a tape. A sealing rubber 60 was attached to the produced electricity storage device 50 and vacuum-dried at about 180 ° C. Then, a lithium foil was attached to the negative electrode 20, and the electricity storage device 50 was placed in a container 70. Then, 3.0 wt% of EMC as a first additive is added to a solution (1.10 mol / L) of LiPF ₆ dissolved in PC (100 vol%), and further VC is 0.1 wt as a second additive. %, And the obtained non-aqueous electrolyte was poured into the container 70, and then the sealing rubber 60 was caulked to produce the lithium ion capacitor 100.

(Example 2)
In Example 2, the amount of VC added was 0.5 wt%. Other conditions were the same as in Example 1.

Example 3
In Example 3, the amount of VC added was 1.0 wt%. Other conditions were the same as in Example 1.

Example 4
In Example 4, the amount of EMC added was 0.1 wt%. Other conditions were the same as in Example 3.

(Example 5)
In Example 5, the amount of EMC added was 1.0 wt%. Other conditions were the same as in Example 3.

(Example 6)
In Example 6, the amount of EMC added was 5.0 wt%. Other conditions were the same as in Example 3.

(Example 7)
In Example 7, the amount of EMC added was 9.0 wt%. Other conditions were the same as in Example 3.

(Example 8)
In Example 8, 3.0 wt% of DMC was added instead of EMC. Other conditions were the same as in Example 3.

Example 9
In Example 9, 3.0 wt% of DEC was added instead of EMC. Other conditions were the same as in Example 3.

(Example 10)
In Example 10, PC (80 vol%) and EC (20 vol%) were used as non-aqueous solvents. Other conditions were the same as in Example 3.

(Example 11)
In Example 11, 1.0 wt% of FEC was added instead of VC. Other conditions were the same as in Example 3.

Example 12
In Example 12, 3.0 wt% of FEC was added instead of VC. Other conditions were the same as in Example 3.

(Example 13)
In Example 13, 5.0 wt% of FEC was added instead of VC. Other conditions were the same as in Example 3.

(Example 14)
In Example 14, 1.0 wt% of MBES was added instead of VC. Other conditions were the same as in Example 3.

(Example 15)
In Example 15, 1.0 wt% LiB (C ₂ O ₄ ) ₂ was added instead of VC. Other conditions were the same as in Example 3.

(Example 16)
In Example 16, 1.0 wt% of LiPF ₂ (C ₂ O ₄ ) ₂ was added instead of VC. Other conditions were the same as in Example 3.

(Example 17)
In Example 17, 1.0 wt% of LiPF ₄ (C ₂ O ₄ ) was added instead of VC. Other conditions were the same as in Example 3.

(Example 18)
In Example 18, 3.0 wt% of DMC was added instead of EMC, and the second additive was not added. Other conditions were the same as in Example 1.

(Example 19)
In Example 19, the second additive was not added. Other conditions were the same as in Example 1.

(Example 20)
In Example 20, 3.0 wt% of DEC was added instead of EMC, and the second additive was not added. Other conditions were the same as in Example 1.

(Comparative Example 1)
In Comparative Example 1, neither the first additive nor the second additive was added. Other conditions were the same as in Example 1.

(Comparative Example 2)
In Comparative Example 2, the first additive was not added. Other conditions were the same as in Example 3.

(Comparative Example 3)
In Comparative Example 3, the first additive was not added. Other conditions were the same as in Example 11.

(Comparative Example 4)
In Comparative Example 4, the first additive was not added. Other conditions were the same as in Example 14.

(Comparative Example 5)
In Comparative Example 5, the amount of EMC added was 18.0 wt%. Other conditions were the same as in Example 3.

(Evaluation methods)
After the lithium ion capacitors of Examples 1 to 20 and Comparative Examples 1 to 5 were fabricated, the capacitance at room temperature and the internal resistance were measured as initial characteristics. Then, the float test which continuously charges for 1000 hours with the voltage of 3.8V in the 85 degreeC thermostat was done. After the float test, the cell was allowed to cool to room temperature, the capacitance and internal resistance were measured, and the rate of change before and after the test was calculated. The results (capacity maintenance rate and internal resistance change rate) are shown in FIG.

(Initial characteristics)
In Examples 1-20 and Comparative Examples 1-5, the electrostatic capacity and internal resistance in the initial characteristics showed good values. This is presumably because cyclic carbonate was used as the non-aqueous solvent and the concentration of LiPF ₆ was set to 0.8 mol / L or more and 1.6 mol / L or less. From the results of Examples 4 to 7, it was confirmed that the initial internal resistance was decreased as the amount of the first additive added was increased.

(High temperature reliability)
In Comparative Example 1, the capacity retention rate was low and the internal resistance change rate was high. This is considered to be because neither the first additive nor the second additive was added to the non-aqueous electrolyte from the comparison result between Example 1 and Comparative Example 1. Next, in Comparative Example 2, although the decrease in the capacity retention rate and the increase in the internal resistance change rate were suppressed in comparison with Comparative Example 1, the internal resistance change rate was 200% or more and was not sufficiently small. This is considered to be because the first additive was not added to the non-aqueous electrolyte from the comparison result between Example 3 and Comparative Example 2. Next, in Comparative Example 3, the decrease in the capacity retention rate and the increase in the internal resistance change rate were suppressed in comparison with Comparative Example 1, but the internal resistance change rate was 200% or more and was not sufficiently small. This is considered to be because the first additive was not added to the non-aqueous electrolyte from the comparison result between Example 11 and Comparative Example 3. Next, in Comparative Example 4, although the decrease in the capacity retention rate and the increase in the internal resistance change rate were suppressed in comparison with Comparative Example 1, the internal resistance change rate was 200% or more and was not sufficiently small. This is considered to be because the first additive was not added to the non-aqueous electrolyte from the comparison result between Example 14 and Comparative Example 4. Next, in Comparative Example 5, the capacity retention rate was low. From the comparison result between Example 3 and Comparative Example 5, this is considered to be because the amount of the first additive added was too large.

On the other hand, in Examples 1 to 20, a decrease in the capacity maintenance rate was suppressed, and the internal resistance change rate was sufficiently small (less than 200%). This is because, in a non-aqueous electrolyte solution using cyclic carbonate as a non-aqueous solvent and LiPF ₆ of 0.8 mol / L or more and 1.6 mol / L or less as an electrolyte, the addition amount to the non-aqueous electrolyte solution is 0.1 wt% or more and 10 This is probably because the chain carbonate contained less than 0.0 wt%.

  In addition, when Examples 18-20 and Examples 1-17 were compared, in Examples 1-17, the internal resistance change rate became smaller. This is considered to be because in Examples 1 to 17, the second additive was added. From the comparison results between Examples 1 to 17 and Examples 18 to 20, it can be seen that the types of the first additive and the second additive are not affected.

  Moreover, when each result of Examples 1-3 is compared, it turns out that it is preferable that the addition amount of a 2nd additive shall be 0.5 wt% or more. On the other hand, when each result of Examples 11-13 is compared, it turns out that it is preferable that the addition amount of a 2nd additive shall be 3.0 wt% or less.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. It can be changed.

DESCRIPTION OF SYMBOLS 10 Positive electrode 11 Positive electrode collector 12 Positive electrode layer 20 Negative electrode 21 Negative electrode collector 22 Negative electrode layer 30 Separator 41, 42 Lead terminal 50 Power storage element 60 Sealing rubber 70 Container 100 Lithium ion capacitor

Claims (7)

An electrolytic solution in which 0.8 mol / L or more and 1.6 mol / L or less of LiPF ₆ is contained as an electrolyte in a cyclic carbonate solvent;
An electrolytic solution for an electrochemical device, comprising: a chain carbonate having an addition amount to the electrolytic solution of 0.1 wt% or more and less than 10.0 wt%.   2. The additive according to claim 1, further comprising at least one of a carbonate ester, a sulfonate ester, and a lithium oxalate complex salt as an additive having an addition amount to the electrolyte of 0.1 wt% to 5.0 wt%. Electrolyte solution for electrochemical devices as described.   The electrolytic solution for an electrochemical device according to claim 2, wherein the carbonate ester is at least one of vinylene carbonate and fluoroethylene carbonate.   The electrolyte solution for an electrochemical device according to claim 2, wherein the sulfonic acid ester is bis (ethanesulfonic acid) methylene.   The electrochemical device according to claim 2, wherein the oxalato complex salt is at least one of lithium bis (oxalato) borate, lithium difluorobis (oxalato) phosphate, and lithium tetrafluorooxalatophosphate. Electrolyte.   The said chain carbonate is at least any one of dimethyl carbonate, ethyl methyl carbonate, and diethyl carbonate, The electrolyte solution for electrochemical devices as described in any one of Claims 1-5 characterized by the above-mentioned. A power storage element in which a positive electrode and a negative electrode are stacked via a separator,
An electrochemical device, wherein the positive electrode active material, the negative electrode active material, or the separator is impregnated with the electrolytic solution for an electrochemical device according to claim 1.

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