JPH08306366A - Nonaqueous electrolyte battery and its manufacture - Google Patents

Abstract

PURPOSE: To smoothly insert a rolled electrode unit in a limited space of a case and prevent leakage in the inside by forming a sticking part in at least one point in the outermost circumferential end part of a separator and sticking the separator. CONSTITUTION: In the case a strip-like separator 3 is set between a cathode sheet 2 and an anode sheet 1 and the resulting whole body is rolled like a coil to give an electrode unit; an adhesive composition is applied to the outermost circumferential end part to form an adhesive part 3a. The end part of the separator is stuck to the corresponding parts in the outermost circumferences of the electrode sheets. A non-aqueous electrolytic battery is manufactured while employing the electrode unit. Consequently, the electrode unit rolled like a coil can be inserted smoothly in a limited space of a case.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-aqueous electrolyte battery and a method for manufacturing the same.

[0002]

2. Description of the Related Art A strip-shaped negative electrode plate having a light metal such as lithium as an active material and a strip-shaped positive electrode plate having manganese dioxide as an active material are provided, and the positive and negative electrode plates are spirally wound with a separator interposed therebetween. The non-aqueous electrolyte battery has a high energy density, is suitable for high rate discharge, and has little self-discharge, and is therefore used in many applications.

[0003] In recent years, as the applications of this spiral type non-aqueous electrolyte battery have expanded, the safety thereof has been reviewed, and not only is it used at high rate discharge, but it is used for a long time at low rate discharge. The usage conditions such as the combined use of high rate and low rate are diversifying, and even in such a case, high reliability that can be safely used is required.

[0004]

Generally, a spiral non-aqueous electrolyte battery has a positive electrode plate, a negative electrode plate, and a separator, and after winding the separator, the outermost end portion of the spiral tape is fixed to fix the separator at the final end portion of the winding. Etc. And it was inserted in the case in this state. In this case, since the outer diameter of the electrode plate group partially increases due to the sticking of tape, etc., when inserting the electrode plate group into the case, the tape or separator protruding outside is scraped by the case and ruptured. However, problems such as internal leaks have occurred.

As a measure for solving the occurrence of such an internal leak, a tape, a protective film 4 or the like is wound around most of the outermost periphery of the electrode plate group as shown in FIG. I was taking measures to prevent it.

However, even in such a method, since the inner volume of the case is limited, in order to fit the spiral electrode plate group in the case, the total length of the electrode plate may be shortened or the thickness thereof may be reduced. However, there is a problem in that the battery capacity is limited to a small amount because it is necessary to devise to reduce the outer diameter of the electrode plate group.

The present invention solves such a problem, and can be smoothly inserted into a limited space of a case.
It is an object of the present invention to provide a non-aqueous electrolyte battery that does not cause internal leakage and has a sufficient capacity.

[0008]

The non-aqueous electrolyte battery of the present invention has at least one bonded portion provided on the outermost end of a separator which constitutes a spiral electrode group together with a strip electrode. is there.

As a method of applying the adhesive to the separator, when the electrode plate is placed on the separator to form an electrode plate group, the adhesive is applied to the end of winding of the separator by brushing, spraying or It is applied by a dropping method.

[0010]

With this structure, since the non-aqueous electrolyte battery of the present invention has at least one adhesive portion at the end of winding of the separator, the separator positioned at the outermost periphery of the electrode plate group can be used. Can be fixed to the surface of the electrode plate, the diameter of the electrode plate group hardly increases at that time, and breakage of the separator when inserting the electrode plate group into the case can be minimized. . Further, since no extra parts such as a tape and a protective film are used, the diameter is hardly expanded, and the spirally wound electrode plate group can be accommodated in the case with the maximum required capacity.

[0011]

The application of an adhesive to a non-aqueous electrolyte battery and a separator thereof according to an embodiment of the present invention will be described in detail below with reference to the drawings.

The negative electrode plate 1 shown in FIG. 1 is made by cutting lithium into a predetermined size. The positive electrode plate 2 is obtained by pressing a paste obtained by mixing manganese dioxide, which is a positive electrode active material, a conductive material and a binder onto a current collector and cutting the paste into a predetermined size.

When a strip-shaped separator 3 is arranged between the positive and negative electrode plates and the whole is spirally wound to form an electrode plate group, a polyolefin-based adhesive composition is sprayed on the outermost peripheral end of the electrode plate group. It was applied and an adhesive portion 3a was provided. The separator 3 is made of a polypropylene porous film, and the separator end portion is bonded to the corresponding portion of the outermost electrode plate. A battery (A) of this example was produced using this electrode plate group. In FIG. 1, 1a is a negative electrode lead and 2a is a positive electrode lead. Next, as a separator, a polypropylene porous film having no adhesive portion was used, and a polypropylene adhesive tape was wound around the outermost periphery of the electrode plate group as shown in FIG. B) was prepared.

In each of the batteries, an electrolytic solution was prepared by dissolving lithium perchlorate in a mixed solvent of propylene carbonate and dimethoxyethane at 1 mol / l.

Table 1 shows the leak defect rates of the battery (A) of this example and the comparative battery (B). Number of tests is 50
It was set to 0 pieces.

[0016]

[Table 1]

From Table 1, it can be seen that no internal leak occurred in the battery (A) of this example, but 4% (20) of internal leak occurred in the comparative battery (B). When these leaked batteries were disassembled and examined, it was found that the tape and the separator at the outermost periphery of the electrode plate group were torn. It is considered that this is because in the comparative battery (B), the diameter of the electrode plate group was increased by the amount of the tape, and the electrode plate group was rubbed by the case when the electrode plate group was inserted into the case and the tape or the separator was torn.

Although the polyolefin-based adhesive composition is used as the adhesive applied to the end portions of the separator in the above example, the same effect can be obtained by using an acrylic-based or silicon-based adhesive composition. Further, the coating method can be appropriately selected by a brush coating method, a dropping method or the like depending on the viscosity of the adhesive composition.

[0019]

As is apparent from the above description of the embodiments,
In the non-aqueous electrolyte battery of the present invention, the spiral electrode plate group can be smoothly inserted into the limited space of the case by providing at least one bonding portion at the outermost peripheral end of the separator and bonding the separator. Without causing internal leaks,
It is possible to provide a non-aqueous electrolyte battery that can secure a negative electrode plate and a positive electrode plate having a sufficient capacity.

[Brief description of drawings]

FIG. 1 is a diagram in the middle of winding an electrode plate group in which an adhesive portion is provided on an end portion of a separator according to an embodiment of the present invention.

FIG. 2 is a diagram showing a state of an electrode plate group after the vibration test.

FIG. 3 is a diagram showing a state of an electrode plate group after a conventional vibration test.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Negative electrode plate 1a Negative electrode lead 2 Positive electrode plate 2b Positive electrode lead 3 Separator 3a Adhesive part 4 Tape

Claims (3)

[Claims] 1. A strip-shaped negative electrode plate containing lithium as a main active material and a strip-shaped positive electrode plate spirally wound with a strip-shaped separator interposed therebetween, and the separator has an outermost end. A non-aqueous electrolyte battery, characterized in that at least one adhesive portion is provided on each part. 2. An electrode is disposed above and below a separator, and when the electrode plate group is formed by spirally winding the electrode plate as a whole, an adhesive is applied to the end of winding of the separator. Manufacturing method of non-aqueous electrolyte battery. 3. The non-aqueous electrolyte battery according to claim 1, wherein the separator comprises a microporous membrane made of polypropylene or polyethylene.