JPH08162128A - Organic electrolyte battery - Google Patents

Abstract

PURPOSE: To provide an organic electrolyte battery in which heat resistance is improved to allow reflow-soldering and also humidity resistance is improved. CONSTITUTION: This organic electrolyte battery is provided with a positive electrode, negative electrode, separator and gasket, using an aprotic organic solution as electrolyte. The positive electrode and/or the negative electrode is composed of an organic semiconductor having a polyacen skeleton structure, and the gasket is formed of a polyamide, and molded by a thermosetting resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coin-type or button-type organic electrolyte battery using an aprotic organic solvent solution as an electrolytic solution.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Application Publication No. Sho 60 (1999)
JP-A-170163 discloses an organic electrolyte battery in which an organic semiconductor having a polyacene skeleton structure is used as a positive electrode and a negative electrode, and an aprotic organic solvent solution is used as an electrolytic solution. In the battery, the battery is airtight, liquidtight, and
The material of the gasket that maintains the insulation of the negative electrode can is extremely important. Conventional gasket materials include chemical resistance, elasticity,
Inexpensive polypropylene has been used because it has excellent creep resistance, good moldability, and injection molding is possible.

Positive and negative electrode cans, separators, organic semiconductors having a polyacene-based skeleton structure and electrolytic solutions of the battery have high melting points or boiling points and excellent heat resistance.
However, the polypropylene used for the gasket has a low heat resistance temperature, so that the conventional battery has a drawback that the heat resistance is inferior. The coin type (button type) organic electrolyte battery is mainly used as a memory backup power source and is often soldered on a printed circuit board. Conventionally, soldering onto a printed circuit board has been performed using a soldering iron, but with the downsizing and higher functionality of equipment, it is necessary to increase the number of electronic components mounted in the same area of the printed circuit board. It has become difficult to secure a gap for inserting a soldering iron due to soldering. Therefore, apply solder to the part to be soldered on the printed circuit board in advance and place the component on that part, or after placing the part, supply the solder globule to the soldered part,
The soldered portion is higher than the melting point of the solder, for example, 200 to 2
A method is used in which a solder is melted by passing a printed circuit board on which components are mounted in a furnace in a high temperature atmosphere set to 30 ° C. (hereinafter referred to as reflow soldering).

In a conventional coin-type (button-type) organic electrolyte battery using a gasket made of polypropylene, polypropylene is melted or deformed during reflow soldering, and positive and negative electrode cans made of stainless steel or aluminum come into contact with each other to cause a short circuit. There was a problem. In order to improve the heat resistance, it is effective to use a gasket made of a polyamide resin having excellent heat resistance, but the polyamide resin has a high hygroscopic property, which reduces the moisture resistance of the organic electrolyte battery. There was a point.

[0005]

DISCLOSURE OF THE INVENTION The inventors of the present invention completed the present invention as a result of continuing diligent research in order to solve the above-mentioned problems, and the purpose thereof is to:
It is an object of the present invention to provide an organic electrolyte battery having improved heat resistance, enabling reflow soldering, and improved moisture resistance.

[0006]

Means for Solving the Problems That is, the present invention provides an organic electrolyte battery comprising a positive electrode, a negative electrode, a separator and a gasket and using an aprotic organic solvent solution as an electrolytic solution, wherein the positive electrode and / or the negative electrode is polyacene. The organic electrolyte battery is characterized in that the gasket is made of an organic semiconductor having a system skeleton structure, the gasket is made of a polyamide resin, and is molded with a thermosetting resin.

In the battery of the present invention, as shown in FIG. 1, conductive pastes 3 and 3'are applied to the inner bottom portions of the positive electrode can 1 and the negative electrode can 6 to form a sheet 2 made of a polyacene organic semiconductor.
2'is inserted into the positive electrode can 1 and the negative electrode can 6 so that the conductive paste 3 and 3'contacts each other, and is opposed to each other via the separator 5. The gasket 4 is compressed by the positive electrode can 1 and the negative electrode can 6 to maintain airtightness, liquid tightness and insulation of the positive and negative electrode cans, and the electrolytic solution is a sheet 2, 2 ′ partially made of a polyacene-based organic semiconductor. It may be in the void inside and partly in the space 7.

The thermosetting resin 8 completely covers the surfaces of the positive and negative electrode cans. The positive electrode terminal 9 and the negative electrode terminal 10 are resistance-welded or laser-welded to the positive electrode can 1 and the negative electrode can 6, respectively, and a part thereof is exposed to the outside of the thermosetting resin 8. The positive electrode can and the negative electrode can are conventional ones, for example, stainless steel or aluminum.

The separator is a conventional separator for batteries or capacitors, such as a porous synthetic resin film,
Inorganic fibers hardened with a resin, paper, etc., preferably made of glass fiber non-woven fabric.

The organic electrolytic solution is a solution in which a salt which produces ions is dissolved in an aprotic organic solvent. Usually, as an electrolytic solution of this type of organic electrolyte battery, aprotic organic solvents such as propylene carbonate and γ-butyrolactone are preferably used as a solvent, and a tetraalkylammonium salt as a salt, for example,

Embedded image (R ₁ , R ₂ , R ₃ and R ₄ represent an alkyl group, R ₁
R ₄ may be the same or different. X is ClO ₄ or BF ₄ ) is preferably used. Salt is usually 0.
It is dissolved in the above-mentioned solvent in a concentration range of 5 to 1.5 mol / l and used as an electrolytic solution.

The terminals are commonly used in batteries or capacitors, and are, for example, stainless steel, nickel, etc., and are preferably made of stainless steel of the same material as the positive and negative electrode cans. The organic semiconductor itself having a polyacene skeleton structure used in the present invention is well known, and is disclosed in, for example, JP-A-61-2.
No. 18060. The organic semiconductor
The powder is pulverized using a ball mill or the like, and a binder and a conductive material are added to the powder, mixed, and then pressure-molded to obtain a polyacene sheet, which is used as a positive electrode and / or a negative electrode.

The gasket is located between the positive and negative electrode cans and is used to maintain the insulation of the positive and negative electrode cans and to keep the battery air-tight and liquid-tight. As its material, it must have chemical resistance to an aprotic organic solvent liquid, and it must be excellent in elasticity and creep resistance because it is placed between the positive and negative electrode cans and compressed. is there. Furthermore, it is more preferable that injection molding is possible, which has good moldability and is suitable for mass production.

The polyamide resin in the present invention is generally referred to as a nylon resin and has an amide bond --CO in the main chain.
It is a polymer having -NH-. Typically, it is a resin synthesized by polycondensation of dicarboxylic acid and diamine, polycondensation of ω-aminocarboxylic acid, or ring-opening polymerization of lactam, and the resin not only has excellent heat resistance but also chemical resistance. , Excellent in creep resistance and elasticity, good in moldability, injection-moldable and inexpensive, and suitable for battery gaskets. Of these, nylon 46 and nylon 66 are more preferable in terms of heat resistance.

The thermosetting resin in the present invention is a resin having the property of being cured by heating to react with unreacted groups remaining in the polymer to increase the degree of polymerization and promote crosslinking to form a network structure. That is, an epoxy resin and a phenol resin are more preferable. The resin has excellent heat resistance and solvent resistance and is suitable for molding coin-type, button-type, etc. organic electrolyte batteries.

The above-described polyamide resin gasket is used in an organic electrolyte battery using an organic semiconductor having a polyacene skeleton structure for the positive electrode and / or the negative electrode, instead of the conventional polypropylene gasket, and Molding with a thermosetting resin improves the heat resistance of the battery, enables reflow soldering, and improves the moisture resistance.

[0016]

EXAMPLES First, a polyacene sheet was manufactured as follows. Japanese Patent Application Laid-Open No. 61-21806 filed by the applicant of the present invention
An insoluble and infusible polyacene film was synthesized by the production method described in Example 1 of JP-A-0. When the electric conductivity of the substance was measured at room temperature by a direct current 4-terminal method, 1
It was 0 ⁻⁴ Ω ⁻¹ · cm ⁻¹ . According to elemental analysis, the atomic ratio of hydrogen atoms / carbon atoms was 0.27. The specific surface area by the BET method was an extremely large value of 2100 m ² / g. Next, the polyacene film was pulverized with a ball mill for 3 hours to obtain a powder. To this powder, 5% by weight of polytetrafluoroethylene and 10% by weight of carbon black were added, mixed, and pressure-molded to obtain a polyacene sheet having a thickness of 0.2 mm. Next, the separator made of the polyacene sheet and the borosilicate glass fiber non-woven fabric was punched into a disc shape, vacuum-dried at 200 ° C. for 3 hours, and then placed in a jam pot and stored.

A gasket obtained by injection-molding nylon 46, which is the polyamide resin of the present invention, was dried by vacuum drying at 100 ° C. for 3 hours and stored in a jam pot. Next, a conductive paste was applied to the bottom of the positive electrode can made of stainless steel, the above-mentioned polyacene sheet was placed on the bottom, pressure-bonded from the top, and then dried at 100 ° C. for 30 minutes. Similarly, a conductive paste was applied to the inner bottom surface of a negative electrode can made of stainless steel, a polyacene sheet was placed thereon, pressure-bonded, and dried at 100 ° C. for 30 minutes. A predetermined amount of propylene carbonate containing tetraethylammonium borofluoride as an electrolytic solution was injected into the positive electrode thus obtained, and the separator was placed. Also, after injecting a predetermined amount of the electrolytic solution into the negative electrode in the same manner, a diameter of 6.8 mm and a height of 0.9 as shown in FIG.
A 6 mm coin type organic electrolyte battery was assembled. All the above-mentioned assembly work was performed in the dehumidifying room.

Next, after stacking two coin type batteries, a stainless steel terminal was laser-welded to the positive electrode can of one battery and the negative electrode can of the other battery, and epoxy resin (made by Nagase Ciba Co., Ltd.) was used. A CY230 curing agent HY951) was used to mold into a diameter of 8.5 mm and a height of 3.5 mm. The organic electrolyte battery of the present invention produced as described above was subjected to reflow soldering such that the surface of the positive and negative electrode terminals had a temperature transition shown in FIG.
Hz, 1mA) changes in Table 1, after reflow soldering,
Table 2 shows the internal resistance after applying a voltage of 5.0 v for 5 days in a constant temperature and constant humidity of 60 ° C. and a relative humidity of 93%.

[0019]

[Table 1]

[0020]

[Table 2]

Comparative Example 1 A coin-type organic electrolyte battery similar to that of the example was assembled using a polypropylene injection-molded gasket, resin-molded and subjected to reflow soldering, and Table 1 shows changes in AC internal resistance. .

COMPARATIVE EXAMPLE 2 A coin type organic electrolyte battery similar to that of the example was assembled using a gasket formed by injection molding nylon 46, and the change in AC internal resistance was observed when reflow soldering was performed without resin molding. Table 1 shows 60 ° C after reflow soldering
Table 2 shows the internal resistance after a voltage of 5.0 v was applied for 5 days in a constant temperature and humidity of 93% relative humidity. In Table 1 and Table 2, the product of the present invention and the conventional product are compared. The product of the present invention does not cause a short circuit with reflow soldering,
No change in AC internal resistance is observed, heat resistance is improved, reflow soldering is possible, and moisture resistance is also improved.

[Brief description of drawings]

FIG. 1 is a coin type (button type) according to an embodiment of the present invention.
Explanatory drawing of a battery.

[Fig. 2] Changes in the surface temperature of the positive and negative electrode terminals with reflow soldering.

[Explanation of symbols]

 1: Positive electrode can 2,2 ': Polyacene-based organic semiconductor sheet 3, 3': Conductive paste 4: Polyamide-based resin gasket 5: Separator 6: Negative electrode can 7: Electrolyte 8: Mold resin 9: Positive electrode Terminal 10: Negative electrode terminal

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shizukuni Yata 2-6-13 Miyanishi, Harima-cho, Kako-gun, Hyogo (72) Inventor Toyoro Harada 5-30-1 Nishitaga, Taihaku-ku, Sendai Seiko Denshi Inside Parts Co., Ltd. (72) Inventor Isamu Shinoda 5-30-1 Nishitaga, Taihaku-ku, Sendai City Seiko Electronic Parts Co., Ltd.

Claims (1)

[Claims] 1. An organic electrolyte battery comprising a positive electrode can, a negative electrode can, a positive electrode, a negative electrode, a separator and a gasket, wherein the positive electrode and / or the negative electrode is made of an organic semiconductor having a polyacene skeleton structure, and the gasket is a polyamide resin. An organic electrolyte battery, which is characterized in that the gasket is covered with a sealant.