KR100391933B1 - Porous polymeric electrolyte and method for making the same - Google Patents

Porous polymeric electrolyte and method for making the same Download PDF

Info

Publication number
KR100391933B1
KR100391933B1 KR20000062328A KR20000062328A KR100391933B1 KR 100391933 B1 KR100391933 B1 KR 100391933B1 KR 20000062328 A KR20000062328 A KR 20000062328A KR 20000062328 A KR20000062328 A KR 20000062328A KR 100391933 B1 KR100391933 B1 KR 100391933B1
Authority
KR
South Korea
Prior art keywords
polymer electrolyte
method
separator
porous
porous polymer
Prior art date
Application number
KR20000062328A
Other languages
Korean (ko)
Other versions
KR20020031253A (en
Inventor
유시만
최석규
유시철
김형권
송원준
박노훈
이승재
Original Assignee
베스 주식회사
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 베스 주식회사 filed Critical 베스 주식회사
Priority to KR20000062328A priority Critical patent/KR100391933B1/en
Publication of KR20020031253A publication Critical patent/KR20020031253A/en
Application granted granted Critical
Publication of KR100391933B1 publication Critical patent/KR100391933B1/en

Links

Classifications

    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage
    • Y02E60/12Battery technologies with an indirect contribution to GHG emissions mitigation

Abstract

The present invention relates to a porous polymer electrolyte and a method for producing the same, the present method is a copolymer of polyvinyl denfluoride, vinyl den fluoride and hexafluoropropylene in an organic solvent, polyvinyl chloride, polymethyl methacrylate Mixing a high molecular compound which is at least one mixture selected from the group consisting of polymethacrylate, polyvinyl alcohol, and polyethylene oxide to form a binder solution; Mixing a silica ball with the binder solution to form a preliminary separator; Evaporating the organic solvent in the preliminary separator; Removing the silica balls included in the preliminary separator to form a porous separator; Cleaning the porous separator; And impregnating the porous separator into a liquid electrolyte containing a metal salt. The porous polymer electrolyte according to the present invention does not need a complicated process for removing the plasticizer included in order to increase porosity, and there is no fear of weakening the mechanical strength due to the pores generated by removing the plasticizer. In addition, by adjusting the size of the silica ball, the user can arbitrarily adjust the pore size and the amount of pores that can obtain the optimum ion conductivity characteristics, the polymer electrolyte exhibits excellent ion conductivity and excellent discharge characteristics.

Description

POROUS POLYMERIC ELECTROLYTE AND METHOD FOR MAKING THE SAME

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymer electrolyte in which lithium salts and liquid components are inhaled, and a method for producing the same, and more particularly, to a polymer electrolyte in which pores of uniform size are formed using silica balls and a method for producing the same. It is about.

With the rapid development of the electric, electronic, telecommunication and computer industries, the demand for high performance and high safety secondary batteries has gradually increased. In particular, according to the trend of thin and short and portable of electrical and electronic products, the secondary battery, which is a key component in this field, is required to be thinned and miniaturized. In response to these demands, lithium polymer secondary batteries have been in the spotlight.

Lithium polymer secondary battery has a lot of researches on polymer electrolyte which has good conductivity compared to liquid electrolyte in terms of electrolyte leakage and safety but low conductivity and gel polymer electrolyte is most suitable for these conditions. It is considered. Gel electrolytes can contain electrolytes in the polymer backbone, which is highly safe and has a conductivity of 10 -3 S / cm. One of the processes for preparing such gel electrolytes is a method of impregnating a lithium salt with a solvent after the components of the battery are assembled, as described in US Pat. No. 5,456,000. In order to prevent the lithium salt or the solvent having high hygroscopicity, the assembly of the battery in the dried atmosphere was prevented to assemble the battery in the undried atmosphere, and later, the manufacturing process was facilitated by impregnating the lithium salt or the solvent in the dried atmosphere. A brief look at the manufacturing process of this patent is as follows. First, as shown in Figure 3a, 8 to 25 wt of a plasticizer, for example DBP (dibutylphtalate) in a copolymer (copolymer) consisting of vinylidene fluoride (VdF: vinylidenfloride) and hexafluoropropylene (HFP) At a temperature of about 120 to 160 ° C. between the positive electrode 3 and the negative electrode 4 and the positive electrode current collector 1 and the negative electrode current collector 2 including the same components as the separator 3 formed by mixing%. Press while applying heat. Then, the DBP contained in the separator is removed with ethanol or diethyl ether. As a result, as shown in FIG. 3B, the pores between the amorphous in the vinylylene fluoride are formed in communication with each other due to the removal of the DBP to form a path through which the electrolyte moves. Next, as shown in FIG. 3C, the electrolyte is impregnated with the structure to impregnate the electrolyte inside the pores. However, this technique has some problems fundamentally.

First, since the mechanical strength of the separator is weak due to the formation of the pore structure, the thickness must be 75 μm or more, and thus there is a problem that the thickness of the secondary battery formed in the multilayer structure is increased.

Second, DBP, which is a plasticizer, needs to be extracted to form a porous structure in the separator, but plasticizers are often left after the extraction process, resulting in insufficient pore formation and a decrease in the amount of electrolyte impregnated in the pores. The performance of the battery is poor.

Third, the plasticizer extraction process is expensive and flammable, causing safety problems.

Fourth, since the prior art uses a DBP that does not have a specific particle shape, the size of the pore structure cannot be arbitrarily adjusted by the manufacturer, and thus there is a problem in that it shows a limit in improving the ionic conductivity of the polymer electrolyte.

It is an object of the present invention to provide a porous polymer electrolyte and a method of manufacturing the same by manufacturing a film of a silica ball and a polymer to improve mechanical strength instead of a plasticizer by solvent casting and removing the silica ball using hydrofluoric acid.

Since the silica ball improves the mechanical strength of the electrolyte membrane, it is possible to overcome the problem of weakening of the mechanical strength after extraction of the plasticizer used to make porosity in the conventional manufacturing method. There is an effect that it is unknown or does not employ a complicated processing step of the plasticizer.

1 is a photograph of a cross-sectional view of a polymer electrolyte prepared according to the present invention using a 0.5 μm silica ball with a scanning electron microscope,

2 is a photograph of a cross-section of a polymer electrolyte according to the present invention prepared using a 1 μm silica ball with a scanning electron microscope,

3A to 3C show schematic diagrams illustrating a manufacturing process of a secondary battery using a polymer electrolyte according to the prior art, respectively.

In order to achieve the above object, the present invention, in the method for producing a porous polymer electrolyte, a copolymer of polyvinyl den fluoride, vinyl den fluoride and hexafluoropropylene in an organic solvent, polyvinyl chloride, polymethyl methacrylate Mixing a high molecular compound which is at least one mixture selected from the group consisting of polymethacrylate, polyvinyl alcohol, and polyethylene oxide to form a binder solution; Mixing a silica ball with the binder solution to form a preliminary separator; Evaporating the organic solvent in the preliminary separator; Removing the silica balls included in the preliminary separator to form a porous separator; Cleaning the porous separator; And it provides a porous polymer electrolyte manufacturing method and a polymer electrolyte comprising the step of impregnating the porous separator in a liquid electrolyte containing a metal salt.

The organic solvent for dissolving the polymer is selected from the group consisting of tetrahydrofuran, acetonitrile, N-methylpyrrolidone, cyclohexanone, and chloroform Or mixtures of two or more are preferred.

In order to prepare a porous electrolyte, the silica ball is preferably added to have a particle size of 0.01-10 μm.

Electrolytic solvents include ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, gamma-butyrolactone ( butyrolactone, dimethylsulfoxide, tetrahydrofuran, and mixtures thereof are preferred.

One or more mixtures selected from the group consisting of LiPF 6 , LiAsF 6 , LiClO 4 , LiN (CF 3 SO 2 ) 2 , LiBF 4 , and LiCF 3 SO 3 as lithium salts are dissolved in the electrolytic solvent to form an electrolyte. to be. The concentration of the lithium salt is preferably 0.5M to 2M. Other alkali metal salts or mercury salts may also be used as the metal salt. The preliminary separator is preferably formed to a thickness of 20 to 70 µm. In addition, the weight ratio of the polymer compound to the weight of the silica ball is 0.1 to 1.5. It is preferable to mix with.

Method for producing a polymer electrolyte according to the present invention is as follows.

10 to 30 g of the polymer compound selected from the polymer compound and 1 to 30 g of the silica ball are mixed with 100 to 150 ml of the organic solvent and mixed at 50 to 100 ° C. for 1 to 5 hours at room temperature. As for the silica ball mixed per 1g of high molecular compounds, 0.1-1.5g is preferable. Next, a separator having a thickness of 20 to 70 µm is formed using a doctor blade or the like. The prepared separator is dried to evaporate the solvent. The dried separator is treated with hydrofluoric acid at a predetermined concentration for 5 to 24 hours. The hydrofluoric acid treated film is then washed with ultrapure water. The washed separator is dried at 50 ° C. for 5 to 24 hours. Next, the separator thus formed is immersed in an electrolytic solution formed by dissolving one or more selected from the metal salt group in an electrolytic solvent selected from an electrolytic solvent group, followed by drying to complete the polymer electrolyte.

The separator of the battery prepared as described above does not need a complicated process for removing the plasticizer included in order to increase porosity, and there is no fear of weakening the mechanical strength due to the voids generated from the removal of the plasticizer. In addition, by adjusting the size of the silica ball, the user can arbitrarily adjust the pore size and the amount of pores that can obtain the optimum ion conductivity characteristics, the polymer electrolyte exhibits excellent ion conductivity and excellent discharge characteristics.

(Example 1)

To 20 ml of tetrahydrofuran (THF), 1 g of polyethylene oxide, 2 g of polyvinylidene fluoride, and 3 g of a silica ball having an average diameter of 0.06 µm are mixed at room temperature for 1 hour, and the temperature is gradually raised to 80 ° C and remixed for 1 hour. This was prepared by using a doctor blade on a Teflon plate 20 to 70㎛ thick film and dried for 3 hours at 50 ℃ and removed silica balls in a hydrofluoric acid solution of a predetermined concentration for 10 hours. The membrane from which the silica balls were removed was washed in ultrapure water, dried at 50 ° C. for 12 hours, and then re-dried at 120 ° C. for 12 hours. Next, the membrane is immersed in a liquid electrolyte (1M LiPF 6 in EC / DEC) to complete the porous polymer electrolyte. Conductivity measurement of the completed polymer electrolyte was carried out at a frequency of 1KHz to 1MHz using an IM6 impedance device, and the result was 1.15 × 10 −3 S / cm.

(Example 2) to (Example 5)

Only the ratio of the silica ball and the other conditions are the same as in Example 1, the results are shown in the table below.

division High polymer (g) Silica ball (g) Ionic Conductivity (S / cm) PVdF PEO P213 2 One 3.0 1.15x 10 -3 S / cm P212 2 One 2.0 1.07x 10 -3 S / cm P211 2 One 1.0 6.67x 10 -4 S / cm P2105 2 One 0.5 5.16x 10 -4 S / cm P210 2 One 0.0 2.0x 10 -4 S / cm

(Example 6)

20 g of tetrahydrofuran is mixed with 1 g of polyethylene oxide, 2 g of polyvinyldenilide, and 2 g of silica ball having an average size of 0.5 μm at room temperature for 1 hour, and then slowly mixed at 80 ° C. for 1 hour. The film was prepared using a doctor blade on a Teflon plate, dried at 50 ° C. for about 3 hours, and then silica balls were removed from the hydrofluoric acid solution at a predetermined concentration for 10 hours. The silica ball-free film was washed in ultrapure water, dried at room temperature for 12 hours, and then re-dried at 120 o C for 12 hours. Next, the membrane is immersed in a liquid electrolyte (1M LiPF 6 in EC / DEC) to complete the porous polymer electrolyte. SEM picture of the completed polymer electrolyte is shown in Figure 1 can be seen that the pores of 0.5 ㎛ is formed. Conductivity measurement of the polymer electrolyte was carried out using an IM6 impedance device at a frequency of 1k-1M Hz to obtain a conductivity of 1 x 10 -3 S / cm.

(Example 7)

To 20 ml of THF, 1 g of PEO, 2 g of PvdF, and 2 g of silica ball with an average size of 1 μm were mixed at room temperature for 1 hour, and slowly mixed at 80 ° C. for 1 hour. The film was prepared using a doctor blade on a Teflon plate and dried at 50 ° C. for about 3 hours, and then silica balls were removed from the hydrofluoric acid solution for 10 hours. The silica ball-free film was washed in ultrapure water, dried at room temperature for 12 hours, and then re-dried at 120 o C for 12 hours. Next, the membrane is immersed in a liquid electrolyte (1M LiPF 6 in EC / DEC) to complete the porous polymer electrolyte. SEM image of the completed polymer electrolyte is as shown in Figure 2 can be seen that the pores of 1㎛ formed. Conductivity measurement of the polymer electrolyte was carried out using an IM6 impedance device at a frequency of 1k-1M Hz to obtain a conductivity of 7 x 10 -4 S / cm.

The porous polymer electrolyte according to the present invention does not require a complicated process for removing the plasticizer included in order to increase porosity, and there is no fear of weakening the mechanical strength due to the voids generated by removing the plasticizer. In addition, by adjusting the size of the silica ball, the user can arbitrarily adjust the pore size and the amount of pores that can obtain the optimum ion conductivity characteristics, the polymer electrolyte exhibits excellent ion conductivity and excellent discharge characteristics. Therefore, there is an excellent effect that can be used for a variety of lithium primary, lithium ion battery, lithium polymer battery, lithium ion polymer battery.

Claims (16)

  1. In the method of manufacturing a porous polymer electrolyte,
    In an organic solvent, at least one selected from the group consisting of polyvinyl denfluoride, copolymers of vinyl denfluoride and hexafluoropropylene, polyvinylchloride, polymethylmethacrylate, polymethacrylate, polyvinyl alcohol and polyethylene oxide Mixing the polymer compound as one mixture to form a binder solution;
    Mixing a silica ball with the binder solution to form a preliminary separator;
    Evaporating the organic solvent in the preliminary separator;
    Removing the silica balls included in the preliminary separator to form a porous separator;
    Cleaning the porous separator; And
    Method for producing a porous polymer electrolyte comprising the step of impregnating the porous separator in a liquid electrolyte containing a metal salt.
  2. The method of claim 1,
    The organic solvent,
    Tetrahydrofuran, acetonitrile, N-methylpyrrolidone, cyclohexanone, chloroform One or two or more mixtures selected from the group consisting of chloroform.
  3. delete
  4. delete
  5. The method of claim 1,
    The metal salt is LiPF 6 , LiAsF 6 , LiClO 4 , LiN (CF 3 SO 2 ) 2 , LiBF 4 , LiCF 3 SO 3 The porous polymer electrolyte production method characterized in that at least two or more selected from the group consisting of.
  6. The method of claim 1,
    The preliminary separation membrane is a porous polymer electrolyte production method, characterized in that formed in a thickness of 20 to 70㎛.
  7. The method of claim 1,
    The silica ball is a porous polymer electrolyte production method characterized in that the diameter of 0.01㎛ 10㎛.
  8. The method of claim 1,
    The weight of the polymer compound and the weight of the silica ball is a method for producing a porous polymer electrolyte, characterized in that mixed in a weight ratio of 0.1 to 1.5.
  9. A porous polymer electrolyte prepared by the method of any one of claims 1 to 8.
  10. delete
  11. delete
  12. delete
  13. delete
  14. delete
  15. delete
  16. delete
KR20000062328A 2000-10-23 2000-10-23 Porous polymeric electrolyte and method for making the same KR100391933B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR20000062328A KR100391933B1 (en) 2000-10-23 2000-10-23 Porous polymeric electrolyte and method for making the same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR20000062328A KR100391933B1 (en) 2000-10-23 2000-10-23 Porous polymeric electrolyte and method for making the same

Publications (2)

Publication Number Publication Date
KR20020031253A KR20020031253A (en) 2002-05-01
KR100391933B1 true KR100391933B1 (en) 2003-07-16

Family

ID=19694894

Family Applications (1)

Application Number Title Priority Date Filing Date
KR20000062328A KR100391933B1 (en) 2000-10-23 2000-10-23 Porous polymeric electrolyte and method for making the same

Country Status (1)

Country Link
KR (1) KR100391933B1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100686816B1 (en) 2005-07-22 2007-02-26 삼성에스디아이 주식회사 Lithium secondary battery

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100686816B1 (en) 2005-07-22 2007-02-26 삼성에스디아이 주식회사 Lithium secondary battery

Also Published As

Publication number Publication date
KR20020031253A (en) 2002-05-01

Similar Documents

Publication Publication Date Title
JP6130413B2 (en) Method for producing gel polymer electrolyte secondary battery, and gel polymer electrolyte secondary battery produced thereby
KR101168360B1 (en) Method for producing electrode composite material
KR100448083B1 (en) Solid electrolyte composite for electrochemical reaction apparatus
US5858264A (en) Composite polymer electrolyte membrane
JP4127989B2 (en) Non-aqueous secondary battery separator and non-aqueous secondary battery
US6949318B2 (en) Polymeric gel electrolyte and lithium battery employing the same
EP2647081B1 (en) Lithium-air battery
US6610109B2 (en) Method of manufacturing lithium secondary cell
JP4159667B2 (en) Method for manufacturing electrode plate for lithium secondary battery
KR100682862B1 (en) Electrode for electrochemical cell, manufacturing method thereof, and electrochemical cell containing the electrode
US7611804B2 (en) Nonaqueous secondary battery and electronic equipment using the same
JP3959708B2 (en) Method for producing positive electrode for lithium battery and positive electrode for lithium battery
KR101585839B1 (en) Secondary battery
US8951669B2 (en) Electrode having porous coating layer, manufacturing method thereof and electrochemical device containing the same
JP4370079B2 (en) Lithium polymer battery
JP4201308B2 (en) Lithium secondary battery separator and lithium secondary battery using the same
US6395430B1 (en) Hybrid polymer electrolyte for lithium battery and method of preparing same
US6861175B2 (en) Nonaqueous electrolyte and nonaqueous electrolyte secondary battery
JP4606705B2 (en) Non-aqueous secondary battery separator and non-aqueous secondary battery
US7135254B2 (en) Multi-layered, UV-cured polymer electrolyte and lithium secondary battery comprising the same
KR100783305B1 (en) A method of assembling a cell
US7615084B2 (en) Secondary battery, and its production process
CN1242498C (en) Diaphragm used for winding type lithium cell with gelatinous polymer electrolyte and its preparation method
US6787269B2 (en) Nonaqueous electrolyte and nonaqueous electrolyte secondary battery
KR101987008B1 (en) Solid polymer electrolytes, methods for manufacturing the same, and lithum cell including thereof

Legal Events

Date Code Title Description
A201 Request for examination
E902 Notification of reason for refusal
E701 Decision to grant or registration of patent right
GRNT Written decision to grant
FPAY Annual fee payment

Payment date: 20110718

Year of fee payment: 9

LAPS Lapse due to unpaid annual fee