JP2003168411A - Nonaqueous secondary battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nonaqueous secondary battery having a high safety wherein the inner short-circuit by shrinkage of a separator is prevented. <P>SOLUTION: In the nonaqueous secondary battery having an electrode winding body wherein a positive electrode (1) in which positive electrode mix layer (1b) is formed on a conductive substrate (1a) and a negative electrode (2) in which a negative electrode mix layer (2b) is formed on a conductive substrate (2a) are wound via a separator (3) whose thickness is 20 μm or less, the nonaqueous secondary battery is constituted by fixing a part or the whole part of the periphery of the separator to a part of the positive electrode or the negative electrode. As the separator whose thickness is 20 μm or less, a polyolefin microporous membrane is preferable, and further, it is preferable that the part of the periphery of the separator is fixed to the positive electrode or the negative electrode by pasting a part of the periphery of the separator to the conductive substrate of the positive electrode or the negative electrode by means of a pressure-sensitive adhesive tape (4) having a material whose melting point is 140°C or more. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-aqueous secondary battery, and more particularly to a highly safe non-aqueous secondary battery that prevents a short circuit due to contraction of a separator.

[0002]

2. Description of the Related Art Non-aqueous secondary batteries typified by lithium-ion batteries and polymer lithium-ion secondary batteries are high-voltage,
Due to the high energy density, its demand tends to increase more and more.

In this non-aqueous secondary battery, the positive electrode has a thickness of 10
A positive electrode mixture-containing paste obtained by pasting a positive electrode active material together with a conductive additive and a binder into a solvent is applied onto a conductive substrate made of aluminum foil or the like having a thickness of about 30 μm, and dried to form a positive electrode mixture layer. The negative electrode produced through the steps is coated with a negative electrode mixture-containing paste in which a negative electrode active material is pasted with a solvent together with a binder on a conductive substrate made of a copper foil having a thickness of about 5 to 15 μm and dried. It is manufactured through the process of forming the negative electrode mixture layer. Then, the positive electrode and the negative electrode are wound via a separator to form an electrode wound body, which is then enclosed together with a non-aqueous electrolyte in an outer casing such as a battery case typified by an aluminum can or an aluminum laminate film. A water rechargeable battery is assembled.

By the way, in the non-aqueous secondary battery having the electrode winding body as described above, in order to ensure safety when an abnormality such as nail puncture occurs, the innermost circumferences of the negative electrode and the positive electrode of the electrode winding body are ensured. It has been proposed to expose the conductive substrate or to provide a metal member having an equipotential with the conductive substrate at the outermost portion or the outermost peripheral portion, and to make them face each other for at least one round through a separator. (Japanese Patent Laid-Open No. 8-153542).

[0005]

However, the inventors of the present invention exposed the negative and positive electrode conductive substrates in the innermost peripheral portion of the electrode winding body based on the description of the above publication, and revealed the exposed portions of each. As a result of a detailed study on the practical application of the battery having the structure opposed to each other, it was found that the structure may rather cause the safety of the battery to be lowered when the capacity of the battery is increased. That is, in order to increase the capacity, it is necessary to increase the filling amount of the active material, and therefore it is necessary to reduce the ratio of constituent elements other than the active material such as the separator, but for the above purpose, the thickness is 20 μm or less. When using the separator of
It was found that in a situation where the temperature of the battery becomes high, such as during rapid charging or a heating test of the battery, a phenomenon in which ignition occurs frequently in a short time after the temperature of the battery increases and dangerous behavior is exhibited.

When the present inventors further investigated this phenomenon, it was found that when a separator having a thickness of 20 μm or less was used, contraction due to temperature rise was extremely likely to occur. Polyolefin separator commonly used as a separator for non-aqueous secondary batteries,
For example, a microporous film made of polyethylene is used at 130 ° C to prevent the battery from becoming dangerous due to heat generation during overcharge.
It has a so-called shut-down function that melts at a certain temperature to block the holes and cut off the current. When the thickness of the separator is 25 μm or more, even if the conventional winding structure described above is adopted, no serious problem occurs in safety during heating.

However, when a separator having a thickness of 20 μm or less is used, for example, the separator begins to shrink at about 80 ° C., which is considerably lower than the above temperature, and then 120
It has been found that when the temperature of the battery rises up to about 140 ° C., the separator does not intervene between the negative electrode and the positive electrode, so that the negative electrode and the positive electrode easily come into contact with each other and an internal short circuit occurs frequently. .

In this state, the solvent of the non-aqueous electrolyte in the battery has a flash point (for example, 1 for ethylene carbonate).
57 ° C, 132 ° C for propylene carbonate) or a chain carbonate with a low flash point (for example,
When diethyl carbonate is used (31 ° C.), the temperature has reached a temperature considerably higher than its flash point, so the sparks generated during the internal short circuit ignite the solvent in the battery, and It will lead to a fire.
Therefore, when a solvent having a low flash point, for example, a chain carbonate such as dimethyl carbonate, methyl ethyl carbonate, and diethyl carbonate is used, the problem of reduced safety due to the internal short circuit becomes particularly serious.

The cause of such a difference in thermal behavior depending on the thickness of the separator has not been clarified at present, but a manufacturing process is different between a thickness of 20 μm or less and a thickness of more than 20 μm. It is presumed that the difference is due to the difference in the method of stretching the separator to reduce the film thickness.

In particular, at the innermost peripheral portion or outermost peripheral portion of the positive electrode or the negative electrode, in order to ensure safety in the event of abnormalities such as nail sticking, a conductive substrate is formed without forming an electrode mixture layer containing an active material. In many cases, the exposed portion is provided, and therefore a short circuit is most likely to occur at the innermost peripheral portion or the outermost peripheral portion of the positive electrode or the negative electrode. That is, since the surface of the metal foil normally used as the conductive substrate of the negative electrode and the positive electrode is smooth and slippery, the static friction force that stops the separator from shrinking is weak, and the separator in contact with the separator is weak. Is likely to contract due to temperature rise, and therefore, an internal short circuit is likely to occur at the innermost peripheral portion or the outermost peripheral portion of the positive electrode or the negative electrode.

Therefore, the present invention solves the problems that occur when using a separator having a thickness of 20 μm or less as described above, and prevents the occurrence of internal short circuit due to contraction of the separator, which is a highly safe non-aqueous secondary liquid. The purpose is to provide a battery.

[0012]

According to the present invention, a positive electrode having a positive electrode material mixture layer formed on a conductive substrate and a negative electrode having a negative electrode material mixture layer formed on a conductive substrate have a thickness of 20 μm or less. In a non-aqueous secondary battery having an electrode winding body wound through, by fixing a part or all of the peripheral portion of the separator to a part of the positive electrode or the negative electrode, to prevent the contraction of the separator, the above problems Is the solution.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The fixing of the peripheral portion of the separator to the positive electrode or the negative electrode is not particularly limited, but the electrode such as the lengthwise end portion or the widthwise end portion of the positive electrode or the negative electrode is fixed. It is most effective to perform it on the portion where the conductive substrate is exposed in the peripheral portion.

As a fixing method, adhesion with an adhesive such as an alkaline adhesive, sticking with an adhesive tape, or welding with ultrasonic waves or heating is generally used. For example, a polyimide tape or polyphenylene is used. A method of attaching and fixing the peripheral portion of the separator to the exposed part of the positive or negative conductive substrate using a heat-resistant adhesive tape based on a material having a melting point of 140 ° C. or higher such as sulfide tape Is preferable because it can be easily adopted. In addition, such fixing of the separator to the electrode does not reduce the capacity so that the end of the electrode (the end of the electrode in the length direction and the end in the width direction of the electrode is referred to as the end of the electrode). (Meaning both) and the position is within 10 mm.

In the present invention, the separator having a thickness of 20 μm or less is not particularly limited, but a polyolefin separator is preferably used from the viewpoints of battery discharge characteristics, cost, shutdown function, durability and the like. Specifically, a polyethylene- or polypropylene-made microporous membrane, a laminated type separator such as a laminated polyolefin microporous membrane or a laminated polyolefin microporous membrane and a non-woven fabric, or the like is preferably used. To be In the case of a thin polyolefin separator, it is easy for large shrinkage to occur due to temperature rise,
According to the present invention, a safe and highly reliable non-aqueous secondary battery can be constructed even when a separator having a large shrinkage ratio is used.

Further, the thinner the separator, the greater the risk of breakage during winding. Therefore, it is generally preferable to use a separator having a thickness of 5 μm or more.

In constructing the non-aqueous secondary battery of the present invention
As a positive electrode active material, LiCoO 2 ₂Such as lithium
Cobalt oxide, LiMn₂O_FourSuch as lithium manga
Oxide, LiNiO₂Lithium nickel oxide such as
Thing, LiNiO₂LiC in which a part of Ni in the above is replaced by Co
o_xNi_1-xO₂(0 <x <1), manganese dioxide, five
Metal oxides such as vanadium oxide and chromium oxide
Can be used, but especially LiNiO₂, LiCoO
₂, LiMn₂O_Four, LiCo_xNi_1-xO₂Such as
The open circuit voltage of the positive electrode when charged as described above is based on Li.
A lithium composite oxide showing 2 V or more is preferable.

The positive electrode is prepared by adding a conductive additive, a binder, a gelling agent, etc. to the above positive electrode active material, if necessary, to prepare a positive electrode mixture, and dispersing the positive electrode mixture in a solvent. A paste containing a positive electrode mixture is prepared (a binder, a gelling agent, etc. may be dissolved or dispersed in a solvent in advance and then mixed with a positive electrode active material, a conductive auxiliary agent, etc.),
The positive electrode mixture-containing paste is applied to a conductive substrate made of aluminum foil or the like, dried to form a positive electrode mixture layer, and then pressure-molded if necessary. However, the method for producing the positive electrode is not limited to the above-exemplified method, and another method may be used.

In the production of the above positive electrode, for example, scaly graphite, acetylene black, carbon black or the like is preferably used as the conductive aid, and as the binder, for example, polyvinylidene fluoride, polytetrafluoroethylene or polyacrylic is used. Acid, styrene-butadiene rubber, fluororubber and the like are preferably used, and as the gelling agent, for example, hexafluoropropylene copolymer and the like are preferably used.

Examples of the negative electrode active material include graphite, pyrolytic carbons, cokes, glassy carbons, fired bodies of organic polymer compounds, mesocarbon microbeads,
Carbon fiber, activated carbon, graphite, carbon materials and S _n O _x, such as carbon colloids, Li can be inserted metal oxides such as SiO _x or metal nitride or the like is preferably used.

For the negative electrode, if necessary, the same binder and gelling agent as in the case of the positive electrode are added to the negative electrode active material and mixed to prepare a negative electrode mixture, and the negative electrode mixture is used as a solvent. A negative electrode mixture-containing paste is prepared by dispersing (a binder, a gelling agent, etc. may be dissolved or dispersed in a solvent in advance and then mixed with a negative electrode active material), and the negative electrode mixture-containing paste is then prepared. Stroke is applied to a conductive substrate made of copper foil or the like and dried to form a negative electrode mixture layer,
It is produced by going through a step of pressure molding as needed. However, the method for producing the negative electrode is not limited to the above-described example, and other methods may be used.

In the production of the positive electrode and the negative electrode, examples of the conductive substrate include aluminum, copper, nickel,
Foil such as stainless steel, punching metal, net, expanded metal and the like are used, but aluminum foil is particularly preferably used as the positive electrode conductive substrate, and copper foil is particularly preferably used as the negative electrode conductive substrate. .

As the non-aqueous electrolyte, either a liquid electrolyte or a gel electrolyte can be used, but since a liquid electrolyte which is usually called an electrolytic solution is often used, the electrolytic solution will be described below with reference to this liquid electrolyte. Will be described in detail.

The electrolytic solution is prepared by dissolving an electrolyte salt such as a lithium salt in a non-aqueous solvent such as an organic solvent. Examples of the organic solvent include ethylene carbonate, propylene carbonate, butylene carbonate and dimethyl carbonate. , Carbonic acid esters such as methyl ethyl carbonate and diethyl carbonate, and γ-
Esters such as butyrolactone and methyl acetate can be used. In addition to the above, ethers such as 1,3-dioxolane and 1,2-dimethoxyethane,
Organic solvents such as sulfur compounds such as sulfolane, nitrogen-containing compounds, silicon-containing compounds, fluorine-containing compounds and phosphorus-containing compounds may be used alone or in admixture of two or more.

As an electrolyte salt dissolved in the above organic solvent
Is, for example, LiPF₆, LiClO_Four, LiBF_Four,
LiAsF₆, LiC_nF_{2n + 1}SO₃(N ≧ 1), (C
_mF _{2m + 1}SO₂) (C_nF_{2n + 1}SO₂) NLi (m, n
≧ 1), (RfOSO₂)₂NLi [Rf has 2 or more carbon atoms
In the above halogenated alkyl group, Rf may be the same
However, Rf may be different from each other.
May be bound, for example, bound to a polymer
May be. ] Are used, and are not particularly limited
No, but LiPF₆And fluorinated organic lithi with 2 or more carbon atoms
Preference is given to um salts and the like. And these electrolyte salts are
Usually, about 0.1 to 2 mol / l is dissolved in the above solvent.
Preferably.

The gel electrolyte corresponds to the above-mentioned electrolytic solution gelled with a gelling agent, and examples of such gelling agent include linear polymers such as polyethylene oxide and polyacrylonitrile, or those. , A polyfunctional polymer that is polymerized by irradiation with actinic rays such as ultraviolet rays and electron beams (for example, pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, ethoxylated pentaerythritol tetraacrylate, dipentaerythritol hydroxypentaacrylate, dipentaerythritol A polymer obtained by polymerizing a tetrafunctional or higher acrylate such as erythritol hexaacrylate and a tetrafunctional or higher methacrylate similar to the above acrylate is used.

[0027]

EXAMPLES Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to only those examples.

Example 1 92 parts by mass of LiCoO ₂ (lithium cobaltate), 5 parts by mass of carbon black, 2 parts by mass of polyvinylidene fluoride, and 1 part by mass of hexafluoropropylene copolymer were mixed with N-methyl-2. -Pyrrolidone was mixed as a solvent with a planetary mixer to prepare a paste containing a positive electrode mixture. The obtained positive electrode mixture-containing paste is intermittently coated on both sides of a conductive substrate made of an aluminum foil having a thickness of 20 μm with a blade coater, dried, subjected to a pressing step, and then cut into a predetermined size to obtain a conductive material. A strip-shaped positive electrode having a length of 340 mm and a width of 51 mm having a positive electrode material mixture layer on a flexible substrate was obtained. However, the positive electrode material mixture layer was not formed in the vicinity of the inner peripheral edge and the outer peripheral edge of the positive electrode, and the exposed portion of the conductive substrate made of aluminum foil was left. Further, the positive electrode material mixture layer was not formed on the outer peripheral surface side of the outermost peripheral portion of the positive electrode, and the exposed portion of the conductive substrate made of aluminum foil was left. Therefore, the size of the portion of the positive electrode on which the positive electrode mixture layer was formed was 320 mm in length on the inner peripheral surface side / 250 mm on the outer peripheral surface side and 51 mm in width.

Further, 92 parts by mass of graphite, 6 parts by mass of polyvinylidene fluoride, and 2 parts by mass of hexafluoropropylene copolymer were mixed in a planetary mixer using N-methyl-2-pyrrolidone as a solvent to prepare a negative electrode mixture. An agent-containing paste was prepared. The obtained negative electrode mixture-containing paste was intermittently coated with a blade coater on a conductive substrate made of a copper foil having a thickness of 10 μm, dried, subjected to a pressing step, and then cut into a predetermined size to obtain a conductive material. A strip-shaped negative electrode having a length of 370 mm and a width of 52 mm, which had a negative electrode mixture layer on the substrate, was obtained. However, in the vicinity of the inner peripheral edge and the outer peripheral edge of this negative electrode, the negative electrode mixture layer was not formed, and the exposed portion of the conductive substrate made of copper foil was left. Therefore, the length of the portion where the negative electrode mixture layer was formed in this negative electrode was 350 mm, and the width was 52 mm.

The above-mentioned positive electrode and negative electrode have a thickness of 16 μm.
It has a mean pore size of 0.05 μm and a melting point of 130 ° C and is made of polyethylene microporous film. Length is 525 mm and width is 54 m.
It was wound through a m separator to obtain a substantially long cylindrical electrode wound body having a major axis of 34 mm and a minor axis of 3.5 mm. From the widthwise ends of the upper and lower sides of the conductive substrate in the portion where the positive electrode mixture layer is not formed in the outermost peripheral portion of the electrode winding body thus obtained and the conductive substrate is exposed 5m each
A part of an adhesive tape having a thickness of 35 μm and a width of 8 mm, which was based on polyphenylene sulfide having a melting point of 140 ° C. or more, was attached to the part up to m. That is, on the upper side of the electrode winding body, the lower side portion of the adhesive tape is attached to the positive electrode conductive substrate, and on the lower side of the electrode winding body,
The upper portion of the adhesive tape was attached to the positive electrode conductive substrate.

Then, the remaining portion of the adhesive tape was attached to the widthwise end of the separator. That is, on the upper side of the electrode winding body, the upper side portion of the adhesive tape is attached to the upper end portion of the separator protruding above the positive electrode,
On the lower side of the electrode winding body, the lower side portion of the adhesive tape was attached to the lower end portion of the separator protruding below the positive electrode. In this way, the widthwise end of the separator corresponding to a part of the peripheral portion of the separator was fixed to the widthwise end of the positive electrode with the adhesive tape.

FIG. 1 is a front view of the structure of the positive electrode, the negative electrode, the separator, and the adhesive tape before winding in the electrode winding body as seen from the positive electrode side, and FIG. 2 is an enlarged view taken along the line AA of FIG. FIG. As shown in these figures, the positive electrode 1 is produced by forming a positive electrode mixture layer 1b on a conductive substrate 1a made of aluminum foil, and most of it is
The positive electrode mixture layer 1b is formed on both surfaces of the conductive substrate 1a, but the outermost peripheral portion of the electrode winding body has the positive electrode mixture layer 1b formed only on the inner peripheral surface side and the outer peripheral surface side. The positive electrode mixture layer 1a is not formed and the conductive substrate 1a is exposed.
Then, the negative electrode 2 is formed by forming the negative electrode mixture layer 2b on both surfaces of the conductive substrate 2a made of copper foil. The separator 3 is interposed between the negative electrode 2 and the positive electrode 1, the separator 3 is larger than the positive electrode 1 and the negative electrode 2, and the upper end portion thereof projects upward from the upper end portions of the positive electrode 1 and the negative electrode 2.
Further, the lower end portion of the separator 3 projects below the lower end portions of the positive electrode 1 and the negative electrode 2.

Then, the lower side portion of the adhesive tape 4 adheres to the upper end portion of the conductive substrate 1a corresponding to the outermost peripheral portion of the positive electrode 1, and the upper side portion of the adhesive tape 4 projects above the positive electrode 1. It adheres to the widthwise end of the separator 3. In addition, the conductive substrate 1a corresponding to the outermost peripheral portion of the positive electrode 1
The lower side portion of the adhesive tape 4 adheres to the lower end portion of the adhesive tape 4, and the upper side portion of the adhesive tape 4 adheres to the widthwise end portion of the separator 3 protruding below the positive electrode 1.

Then, as the electrolytic solution, LiPF ₆ was dissolved in a mixed solvent of 30 parts by mass of ethylene carbonate, 30 parts by mass of propylene carbonate and 40 parts by mass of diethyl carbonate so as to have a concentration of 1.2 mol / l. The non-aqueous electrolyte solution prepared as described above was used.

After the above-mentioned wound electrode body and the electrolytic solution were enclosed in an outer packaging material made of an aluminum laminate film, the
Heat at 90 ° C. for 90 minutes, then cool to room temperature.
The non-aqueous secondary battery (polymer lithium ion secondary battery) by gelling the hexafluoropropylene copolymer contained in the positive electrode mixture of the above and the negative electrode mixture of the negative electrode 2
Was produced.

The aluminum laminate film is composed of a three-layer laminate film of a polyester film, an aluminum foil and a modified polyolefin resin film, and two aluminum laminate films are used for encapsulating the electrode winding body. One of them is formed into a container, the other is formed into a plate, and the electrode winding body or the like is put in the recess of the container-shaped aluminum laminated film, and the plate-shaped aluminum laminated film is formed on the modified polyolefin resin films. Are arranged so as to face each other, and the modified polyolefin resins are heated and heat-sealed to each other, thereby encapsulating the electrode winding body, the electrolytic solution, and the like in an exterior body made of an aluminum laminate film.

Example 2 The sticking position of the adhesive tape was set to the winding end portion of the electrode winding body, and the same adhesive tape having a length of 50 mm and a width of 20 mm, which was based on polyphenylene sulfide as in Example 1, was applied to the winding end portion. A non-aqueous secondary battery (polymer lithium ion secondary battery) was produced in the same manner as in Example 1 except that it was attached.

Example 3 The sticking position of the adhesive tape was set to the winding start portion of the electrode winding body, and the same adhesive tape having a length of 50 mm and a width of 20 mm, which was based on polyphenylene sulfide as in Example 1, was placed in the winding start portion. A non-aqueous secondary battery (polymer lithium ion secondary battery) was produced in the same manner as in Example 1 except that it was attached.

Example 4 In the same manner as in Example 3 except that an adhesive tape based on polyimide was attached instead of the adhesive tape based on polyphenylene sulfide in Example 3, a non-aqueous secondary battery ( Polymer lithium ion secondary battery) was produced.

Example 5 Instead of sticking the adhesive tape based on polyphenylene sulfide in Example 2, an acrylic adhesive was applied to the separator, and the separator was exposed to the positive conductive substrate by the acrylic adhesive. A non-aqueous secondary battery (polymer lithium ion secondary battery) was produced in the same manner as in Example 2 except that it was directly fixed to the portion.

Comparative Example 1 A non-aqueous secondary battery (polymer lithium ion secondary battery) was prepared in the same manner as in Example 1 except that the adhesive tape based on polyphenylene sulfide as in Example 1 was not attached. did.

Each of the batteries of Examples 1 to 5 and Comparative Example 1 described above was discharged from 3.0 V at a 1 C charge rate to 2.5.
Time constant current constant voltage charging, 4.25V full charge state, then insert into constant temperature bath, temperature rise from room temperature 5 ℃
The temperature was raised to 130 ° C./min. After the temperature of the inside of the constant temperature bath reached 130 ° C., the voltage of the battery was measured 60 minutes later, and the voltage having a voltage of 4.0 V or more was used as a reference for not causing an internal short circuit. The results are shown in Table 1 with “x” indicating that the voltage was less than 4.0V.

In the same manner as above, a fully charged battery of 4.25 V was inserted into a constant temperature bath, and the temperature was raised from room temperature to 150 ° C. at a temperature rising rate of 5 ° C./min. After the temperature in the constant temperature bath reached 150 ° C., the voltage of the battery was measured 10 minutes afterward, and a battery having a voltage of 4.0 V or higher was used as a reference for not causing an internal short circuit. The results are shown in Table 1 with “x” indicating that the voltage was less than 4.0V.

Furthermore, each of the batteries of Examples 1 to 5 and Comparative Example 1 was discharged from 3.0 V to 2.5 C at a 1 C charge rate.
Time constant current-constant voltage charging was performed to obtain a fully charged state of 4.20V. A constant current-constant voltage charge (overcharge) of 12 V was performed on these batteries at a 1C charge rate, and the current cutoff after the shutdown of the separator continued to function was "O", and the one that could not be maintained was "X". The results are shown in Table 1.

[0045]

[Table 1]

As is clear from the results shown in Table 1, the batteries of Examples 1 to 5 did not cause a voltage drop even in the heating test at 130 ° C. and 150 ° C. and maintained a voltage of 4.0 V or more, and The current interruption could be maintained even after the shutdown function of the separator was activated in the overcharge test.

This is because, in the batteries of Examples 1 to 5, since a part of the peripheral portion of the separator was fixed to the positive electrode, the occurrence of internal short circuit due to contraction of the separator during heating could be prevented. It is thought to be due to.

[0048]

As described above, according to the present invention, it is possible to provide a highly safe non-aqueous secondary battery which prevents the occurrence of an internal short circuit due to the contraction of the separator.

[Brief description of drawings]

FIG. 1 is a front view of the configurations of a positive electrode, a negative electrode, a separator, and an adhesive tape before winding in an electrode winding body of a battery of Example 1 of the present invention, as viewed from the positive electrode side.

FIG. 2 is an enlarged cross-sectional view taken along the line AA of FIG.

[Explanation of symbols]

1 positive electrode 1a conductive substrate 1b Positive electrode mixture layer 2 Negative electrode 2a conductive substrate 2b Negative electrode mixture layer 3 separator 4 adhesive tape

Continued front page    (72) Inventor Naoto Sugi Building             Hitachima, 1-88, Torora, Ibaraki City, Osaka Prefecture             Within Kucsel Co., Ltd. (72) Inventor Masaki Tateishi             Hitachima, 1-88, Torora, Ibaraki City, Osaka Prefecture             Within Kucsel Co., Ltd. F term (reference) 5H021 AA06 BB11 EE04 HH03 HH06                       HH10                 5H029 AJ12 AK03 AL01 AL02 AL06                       AL07 AL08 AM02 AM03 AM04                       AM05 AM07 CJ22 DJ04 EJ12                       HJ12 HJ14

Claims (3)

[Claims] 1. A positive electrode having a positive electrode mixture layer formed on a conductive substrate and a negative electrode having a negative electrode mixture layer formed on a conductive substrate are wound with a separator having a thickness of 20 μm or less interposed therebetween. A non-aqueous secondary battery having an electrode winding body, wherein a part or all of a peripheral portion of the separator is fixed to a part of a positive electrode or a negative electrode. 2. The non-aqueous secondary battery according to claim 1, wherein a separator having a microporous film made of polyolefin is used as the separator having a thickness of 20 μm or less. 3. A part of the peripheral portion of the separator has a melting point of 1
The non-aqueous secondary battery according to claim 1 or 2, wherein the non-aqueous secondary battery is attached to a conductive substrate of a positive electrode or a negative electrode with an adhesive tape based on a material of 40 ° C or higher.