WO2008146895A1

WO2008146895A1 - Electrolyte and electric/electronic component using the same

Info

Publication number: WO2008146895A1
Application number: PCT/JP2008/059955
Authority: WO
Inventors: Shinji Naruse
Original assignee: Dupont Teijin Advanced Papers, Ltd.
Priority date: 2007-05-31
Filing date: 2008-05-23
Publication date: 2008-12-04
Also published as: TW200912958A

Abstract

Provided is an electrolyte, which contains an aramid, ionic species and an organic solvent, is suitable as an electrolytic solution in an electric/electronic component, has high conductivity and withstand voltage and is chemically and electrochemically stable.

Description

Specification

Electrolyte and electrical and electronic parts using it

The present invention relates to an electrolyte useful for electrical and electronic parts such as non-aqueous batteries and capacitors. Background art

As symbolized by recent advances in electrical and electronic equipment such as portable communication equipment and high-speed information processing equipment, there is a remarkable reduction in size and weight of electronic equipment and performance. In particular, expectations are high for compact, lightweight, high-capacity, high-performance batteries and capacitors that can withstand long-term storage, and a wide range of applications are being made, and parts development is progressing rapidly. In response to this, various electrical and electronic components, for example, electrolytes that move ions between the positive and negative electrodes so that the movement of electrons can take place and take out electrical energy, can There is a growing need. For electrolytes used between conductive members such as anodes and cathodes in batteries, capacitors, and other electrical components, conventional solvents include, for example, ethylene carbonate, propylene carbonate, dimethylolate carbonate, and jetinolet. Carbonate, ethinoremethinorebonate, butylene carbonate, glutaronitrile, adiponitrile, acetonitonyl, methoxyacetonitrile, 3-methoxypropetolinol, y-butyrolacton, γ-valerolataton, S / leforane, 3 -Methylsulfolane, nitroethane, nitromethane, trimethinole phosphate, Ν-methyloxazolidinone, Ν, Ν-dimethylformamide, Ν-methylpyrrolidone, dimethyls ^ / oxide, Ν, Ν, mono-imidazolidinone, Amidine, water, A mixture of two or more of them is used.

Examples of the ionic species include the following combinations of cations and ions. (1) 'Cation: quaternary ammonium ion, quaternary phosphonium ion, lithium ion, sodium ion, ammonium ion, hydrogen ion, etc., and mixtures thereof.

(2) Anion: perchlorate ion, borofluoride ion, hexafluorophosphate ion, sulfate ion, hydroxide ion, etc., and mixtures thereof. The combination of these solvents and ionic species has good physical properties as an electrolyte. However, in recent years, the combination of these solvents and ionic species does not always adequately cope with the increase in capacity and output required for batteries and capacitors for electric vehicles. I can't.

For electrolytes used between conductive members such as anodes and cathodes in electrical and electronic parts such as batteries and capacitors that require high capacity and high output.

(1) Good conductivity,

(2) High decomposition voltage,

(3) Wide operating temperature range,

(4) Chemical and electrochemical stability (long life)

It is necessary to satisfy these four characteristics simultaneously. In particular, long life is considered to be a very important requirement for electric and electronic parts that use large currents, such as batteries as drive power sources for electric vehicles. Disclosure of the invention

The object of the present invention is to be suitable as an electrolytic solution in electrical / electronic components, capable of withstanding a large current due to high capacity and large output, high conductivity, high withstand voltage, chemical ■ electrochemically stable It is to provide an electrolyte material.

The present invention provides an electrolyte characterized by containing a amide, an ionic species, and an organic solvent.

The electrolyte of the present invention is useful as an electrolyte used between conductive members in electrical and electronic parts because it has a sufficiently high electrical conductivity, high withstand voltage, long life, and a wide operating temperature range. A battery and a capacitor using the electrolyte of the present invention Electric and electronic parts such as can be used advantageously in a large current environment such as an electric vehicle.

Hereinafter, the electrolyte of the present invention will be described in more detail. Aramid

The amide used in the electrolyte of the present invention includes a linear polymer compound in which 60% or more of amide bonds (one CONOH) are directly bonded to an aromatic ring (for example, a benzene ring). Examples of such amides include polymetaphenylene isophthalamide and copolymers thereof, polyparaphenylene terephthalamide and copolymers thereof, poly (paraphenylene) -copoly (3,4 diphenyl ether) terephthal amine. And so on. These amides are industrially produced by, for example, known interfacial polymerization methods and solution polymerization methods using isophthalate salt and meta-phenylenediamine, and are obtained as commercial products. However, it is not limited to this. Among these amides, in particular, polymetaphenylene isophthalamide is preferably used since it has good molding processability, thermal adhesiveness, flame retardancy, heat resistance and the like. Ionic species

As the ionic species used in the electrolyte of the present invention, those conventionally used in electrolytes used between conductive members such as anodes and positive electrodes in electric / electronic parts such as batteries and capacitors are also used. Is possible. For example, the following combinations of cation and pheon can be mentioned, but are not limited to these combinations. Good solubility in organic solvents and desired properties such as electrical conductivity and withstand voltage For example, any material can be used as long as it has an electrical conductivity of lm S / cm or more (20 ° C.) and a withstand voltage of 2 V or more in a state dissolved in an organic solvent.

(1) Cations: Quaternary ammonium ion, quaternary phosphonium ion, lithium ion, sodium ion, ammonium ion, Hydrogen ions, etc., and mixtures of two or more thereof.

(2) Anion: Perchlorate ion, borofluoride ion, hexafluorophosphate ion, sulfate ion, hydroxide ion, etc., and a mixture of two or more thereof. Organic solvent

As the organic solvent used in the present invention, those conventionally used in electrolytes used between conductive members such as anodes and cathodes in electrical and electronic parts such as batteries and capacitors can be used as well. For example, ethylene carbonate, propylene carbonate, dimethylolate, jetyl carbonate, ethylmethyl carbonate, butylene carbonate, glutaronitrinole, adiponitrile, acetonitonyl, methoxycetate etyl, 3- Methoxip oral pionitrile, y-butyroratatone, y-valerolataton, sulfolane, 3-methylolsulfolane, nitroethane, nitromethane, trimethyl phosphate, N-methyloxazolidinone, N, N-dimethylformamide, N-methylpyrrolidone, dimethyls Examples include hydride, N, N 'mono-methylimidazolidinone, amidin, and mixtures of two or more thereof, but exhibit good solubility of ionic species, such as electrical conductivity, withstand voltage, etc. If the characteristics show desired values (for example, if the electrical conductivity is 1 m SZ cm or more (20 ° C) and the withstand voltage is 2 V or more in the state in which the ionic species is dissolved), it is limited to these. It is not something. Among these, ethylene carbonate, propylene carbonate, dimethylolate carbonate, jetyl carbonate, ethylene glycol, propylene carbonate, dimethylolate, etc. A carbonate-based organic solvent containing a carbonate bond in the molecule, such as thiomethylocarbonate and butylene carbonate, is suitable. Crystallinity The degree of crystallinity in the present invention is a standard for classifying aramid crystals and non-crystals, and represents the ratio of the crystal portion in the entire aramid. If the crystallinity of the aramid used is too high, it will be difficult to swell even if it has a high affinity with an organic solvent. Therefore, it is generally preferably 15% or less, particularly preferably 10% or less. If the crystallinity of the aramid used exceeds 15%, homogenization is difficult after mixing with an organic solvent, and the withstand voltage of the electrolyte may be lowered.

In this specification, the crystallinity of the aramide is the same as the diffraction peak value measured by the X-ray wide-angle scattering method, the Nomettas (r) paper measured by the same X-ray wide-angle scattering method. And the relative value when the crystallinity of Nomex (r) paper 5 T 4 11 is 23%. Average particle size

In the present specification, the average particle size of aramide is expressed as a particle size having a cumulative weight of 50% by weight. The aramid used in the present invention is preferably spherical, since the spherical shape has the largest surface area and swells quickly upon contact with an organic solvent. In addition, the aramid is generally preferably in the form of particles having an average particle size of 200 mm or less. Basically, the smaller the average particle size, the better the aramid, since the surface area per unit weight is larger. However, if it is too small, handling such as mixing becomes difficult. A spherical particle having an average particle diameter within the range is particularly preferable. Electrolyte production

The electrolyte of the present invention can be prepared by mixing the aramid, ionic species and organic solvent described above. The order of mixing is not particularly limited as long as the electrolyte is kept in a homogeneous state, such as swelling and dissolution, but in order to prepare a swollen homogeneous gel, it is usually necessary to first mix an ionic species and an organic solvent. Later, it is preferable to mix with aramid in order to maintain a homogeneous state. Also, electrical conductivity, withstand voltage Other additives such as antioxidants can be mixed as long as the properties desired for the electrolyte are not substantially adversely affected.

In addition, the preparation of the electrolyte in the presence of the separator facilitates handling, and in particular, a heat-resistant separator such as the aramid thin leaf material described in Japanese Patent Application Laid-Open No. 20 03-3-065 595. If aramid, ionic species, and organic solvent are mixed in the presence of water to form a uniform gel, a highly workable and heat resistant member in which the electrolyte and separator are integrated can be produced. Application

The electrolyte of the present invention is a separator such as a ramid thin leaf material as an electrolyte used between a conductive member such as a battery, a capacitor, etc., which requires a high capacity and a large output, and an anode, a positive electrode, etc. The base material is impregnated, or as described above, aramid, ionic species, and organic solvent are mixed in the presence of a heat-resistant separator such as aramid thin leaf material to form a homogeneous gel, and the electrolyte and separator are integrated. Later, it can be incorporated as a non-aqueous electrolytic battery, particularly as an interelectrode separator such as a lithium secondary battery or an electric double layer capacitor.

Electric and electronic parts such as a battery and a capacitor using the electrolyte of the present invention can be advantageously used as a power source for a mobile phone, a computer, etc., or as a power source for an electric vehicle, a hybrid automobile, or the like. Example

Hereinafter, the present invention will be described more specifically with reference to examples. These examples are merely examples and are not intended to limit the contents of the present invention. Physical property measurement method

(1) Determination of gelation

After mixing aramid and an organic solvent in which ionic species had been dissolved in advance, the mixture was stirred and was not separated into two layers. (2) Electric conductivity

Measurements were made in a 30 cc sample bottle using an electrical conductivity meter. .

(3) Hygroscopicity

The change in weight after storage for 16 hours in an atmosphere at a temperature of 23 ° C and a relative humidity of 55% was measured.

(4) Crystallinity

The crystallinity of Normetus (r) paper 5 T4 11 (manufactured by DuPont Teijin Advanced Paper Co.) was measured as a relative value based on 23% by the X-ray wide angle scattering method. Examples 1 and 2

Prepare a 1.5M propylene carbonate (lithium battery grade, manufactured by Kishida Chemical Co., Ltd.) solution of N, N, N-triethinole N-methylammonium tetraf / leoloborate (TEMA) and add polyヱ Nylene sophthalamide (crystallinity 3%, average particle size 90 μπι) was mixed in the proportions shown in Table 1 and the electrical conductivity and hygroscopicity were measured. The results are shown in Table 1. Comparative Example 1

A 1.5Μ propylene carbonate (made by Kishida Chemical Co., Ltd., lithium battery grade) solution was prepared, and the electrical conductivity and hygroscopicity were measured. The results are shown in Table 1. table 1

The electrolytes of Examples 1 and 2 have an electric conductivity in a range that can be used as an electrolyte used between conductive members of electric and electronic parts, and have reduced hygroscopicity. Therefore, water decomposes the organic solvent. However, it is unlikely that the characteristics of electrical and electronic parts will deteriorate, especially the withstand voltage, and it is thought that the service life is extended.

In addition, the electrolyte of Example 2 has a gelled structure and contains a amide that is homogeneous and inherently has high electrochemical stability. .

Further, since the electrolytes of Examples 1 and 2 contain aramid, the freezing point of the organic solvent is lowered, it can be used at a low temperature, and it can be used at a high temperature due to the high heat resistance of aramid. It is thought that the life has been extended.

From the above, the electrolyte of the present invention is useful as an electrolyte used between conductive members in electric and electronic parts such as batteries and capacitors in electric vehicles.

Claims

The scope of the claims

1. an electrolyte characterized by containing an aramid, an ionic species and an organic solvent,

2. The electrolyte according to claim 1, wherein the aramid is polymetaphenylene isophthalamide.

3. The electrolyte according to claim 1 or 2, wherein the crystallinity of the aramid is 15% or less.

4. The electrolyte according to any one of claims 1 to 3, wherein the aramid is a spherical particle having an average particle diameter of 200 μm or less.

5. The ionic species is a combination of cation and anion, and the electric conductivity is 1 m S / cm or more (20 ° C) and the withstand voltage is 2 V or more when dissolved in an organic solvent. The electrolyte according to any one of claims 1 to 4, wherein the electrolyte is characterized by the above.

6. The electrolyte according to any one of claims 1 to 5, wherein the organic solvent is a carbonate-based organic solvent.

7. An electrical and electronic component comprising the electrolyte according to any one of claims 1 to 6 between conductive members.

8. A battery comprising the electrolyte according to any one of claims 1 to 6 between conductive members.

9. A capacitor comprising the electrolyte according to any one of claims 1 to 6 between conductive members.