JP2001068160A - Flat nonaqueous electrolyte secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flat nonaqueous electrolyte secondary battery with excellent high rate discharging characteristics. SOLUTION: This secondary battery has a metal negative electrode case 5 also acting as a negative electrode terminal and a metal positive electrode case 2 also acting as a positive electrode terminal fit through an insulating gasket 6, and sealing structure formed by crimping the positive electrode case or the negative electrode case, and contains a power generating element formed by facing the positive electrode and the negative electrode through a separator 3 and a nonaqueous electrolyte. The facing area of the positive and negative electrodes is made larger than the opening area of the insulating gasket. Thereby, such an advantage that the battery size is small and productivity is high is kept, and at the same time, high rate discharge capacity is substantially increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a flat non-aqueous electrolyte secondary battery, and more particularly to a flat non-aqueous electrolyte secondary battery having improved heavy load discharge characteristics.

[0002]

_2. Description of the Related Art Metal oxides such as MnO ₂ and V ₂ O ₅ or inorganic compounds such as fluorinated graphite are used as positive electrode active substances.
Alternatively, an organic compound such as polyaniline or a polyacene structure is used, and a metal lithium or an organic compound such as a lithium alloy or a polyacene structure, or a carbonaceous material capable of absorbing and releasing lithium, or containing lithium titanate or lithium is used as a negative electrode. Using an oxide such as silicon oxide, the electrolyte is propylene carbonate, ethylene carbonate, butylene carbonate, diethyl carbonate, dimethyl carbonate, methyl ethyl carbonate, dimethoxyethane, γ-butyl lactone in a non-aqueous solvent such as LiClO ₄ , LiPF ₆ , LiBF ₄ , L
iCF ₃ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ , LiN
A flat non-aqueous electrolyte secondary battery using a non-aqueous electrolyte in which a supporting salt such as (C ₂ F ₅ SO ₂ ) ₂ is dissolved and the outermost diameter of the battery is long relative to the total battery height such as a coin shape or a button shape is It has already been commercialized, and is applied to applications such as a backup power supply for SRAMs and RTCs, and a main power supply for wristwatches that do not require battery replacement, in which discharge is performed with a light load having a discharge current of several to several tens of μA.

[0003] These flat non-aqueous electrolyte secondary batteries such as coin type and button type generally have a structure as shown in FIG. That is, the metal negative electrode case 5 also serving as the negative electrode terminal and the metal positive electrode case 1 also serving as the positive electrode terminal are:
The positive electrode case 1 is fitted through the insulating gasket 6.
Has a sealing structure which is swaged by swaging, and a tablet-shaped positive electrode 2 and a negative electrode 4 each having a diameter slightly smaller than the opening diameter of the insulating gasket 6 are impregnated therein with a non-aqueous electrolyte. Single or multilayer separator 3
, And are arranged to face each other.

[0004] The flat nonaqueous electrolyte secondary batteries such as the coin type and button type described above have advantages in that they are easy to manufacture, are excellent in mass productivity, and are excellent in long-term reliability and safety. In addition, since the structure is simple, the biggest feature of these batteries is that they can be miniaturized.

On the other hand, the miniaturization of devices used has been accelerated, especially for small information terminals such as mobile phones and PDAs, and accordingly, it is essential to reduce the size of secondary batteries as main power supplies. I have. Conventionally, these power sources include lithium-containing oxides such as lithium cobalt oxide as the positive electrode active substance,
Lithium ion secondary battery using carbonaceous material for negative electrode,
Alkaline secondary batteries such as nickel-metal hydride secondary batteries using nickel oxyhydroxide as the positive electrode active material and a hydrogen storage alloy as the negative electrode active material have been used. After applying or filling an active substance layer on the body to form an electrode, welding the tab terminal to the center of the electrode, winding or laminating it to form an electrode group, and further complicating the tab terminal taken out from the center of the electrode group The battery was fabricated by bending it into a safety element, a sealing pin, and a battery can.

As described above, these batteries are manufactured through a complicated manufacturing process, so that workability is inferior, miniaturization of parts is difficult, and furthermore, space in the batteries is required to prevent short-circuiting of the tab terminals. It is necessary to provide a large number of components such as a safety element and the like in the battery, and the size of the battery has almost reached the limit at present.

[0007]

In view of the above, the inventors of the present invention did not reduce the size of a cylindrical or prismatic lithium ion secondary battery or nickel-metal hydride secondary battery, but reduced the size of the flat non-rechargeable battery described above. An attempt was made to increase the output of the water electrolyte secondary battery. First, the present inventors used a high-capacity, high-potential lithium cobalt oxide as the positive electrode active substance, and a graphitized carbonaceous material with a high capacity and good voltage flatness as the negative electrode active substance, respectively. In accordance with the manufacture and structure of the non-aqueous electrolyte secondary battery, the positive electrode and the negative electrode were formed into tablets slightly smaller than the gasket to produce a battery.

[0008] However, although the battery manufactured in this manner has excellent characteristics as compared with the conventional flat non-aqueous electrolyte secondary battery, the battery produced when discharged at a large current required as a main power source of a small portable device. The characteristics of the portable power supply are far from satisfactory, and the main power supply for small portable devices was not at a level that was completely satisfactory.

[0009] It is an object of the present invention to raise the heavy load discharge characteristics of a small flat non-aqueous electrolyte secondary battery to an unprecedented level, and it is an object of the present invention to provide a flat non-aqueous electrolyte excellent in heavy load discharge characteristics. It is an object of the present invention to provide an electrolyte secondary battery.

[0010]

Means for Solving the Problems The present inventors have conducted intensive studies on the improvement of the heavy load discharge characteristics of the above-mentioned flat non-aqueous electrolyte secondary battery, and as a result, the conventional flat non-aqueous electrolyte secondary battery has It has been found that the heavy-load discharge characteristics are dramatically improved by making the electrode area much larger than that.

That is, a metal negative electrode case also serving as a negative electrode terminal and a metal positive electrode case also serving as a positive electrode terminal are fitted via an insulating gasket, and the positive electrode case or the negative electrode case is caulked by caulking. A power generating element including an electrode group in which at least a positive electrode and a negative electrode are opposed to each other with a separator interposed therebetween, and a flat non-aqueous electrolyte secondary battery including a non-aqueous electrolyte therein, wherein the electrode group It has been found that a flat nonaqueous electrolyte secondary battery having remarkably excellent heavy-load discharge characteristics can be provided by making the area of the positive and negative electrodes facing each other larger than the opening area of the insulating gasket.

It is presumed that it is effective to increase the electrode area in order to improve the heavy load discharge characteristics. However, in the case of the conventional flat nonaqueous electrolyte secondary battery, one tablet-shaped positive electrode and one tablet-shaped negative electrode are used. Since the battery was housed in the battery in such a manner as to be inscribed in the insulating gasket at a time, the facing area where the positive and negative electrodes faced each other with the separator interposed therebetween was inevitably smaller than the opening area of the insulating gasket. Although it is possible to slightly increase the electrode area by reducing the thickness of the gasket, it is theoretically impossible to store an electrode with an opposing area that exceeds the opening area of the gasket in the battery. there were.

The inventors of the present invention have made a dramatic change from the conventional art and have placed the electrodes in a multi-layered battery case of a very small flat battery such as a coin or a button to form an electrode group. It is possible to accommodate an electrode group in which the total area of the positive and negative electrodes facing each other is larger than the opening area of the insulating gasket. In other words, a secondary battery having a large capacity such as a cylinder or a prism has an example in which an electrode having several tens of layers is housed, but these batteries have a complicated structure as described above, and the It has been difficult to apply the structure to a small flat non-aqueous electrolyte secondary battery such as a coin type or a button type. Also, even if it is applied, it is impossible to maintain the advantages of a flat non-aqueous electrolyte secondary battery such as small size and excellent productivity. No effort has been made in the past to store an electrode group having a positive and negative electrode facing area larger than the opening area of the insulating gasket in the water electrolyte secondary battery.

Hereinafter, how the present inventors have realized the flat nonaqueous electrolyte secondary battery of the present invention will be described. First, various forms can be considered for storing an electrode having a positive / negative electrode facing area larger than the opening area of a gasket in a flat nonaqueous electrolyte secondary battery. It was found that it is preferable to house the electrodes as an electrode group in which the electrodes are stacked so as to have the positive and negative electrode facing portions in the directions. Because, in order to obtain excellent heavy load discharge characteristics, the electrode area should be as large as possible, the number of parts should be reduced as much as possible, the space in the small battery should be used effectively, and the electrode group and the amount required for discharge should be reduced. It is necessary to store the water electrolyte in the battery, and such a storage method as an electrode group in which electrodes are stacked so as to have the positive and negative electrode facing portions in the horizontal direction with respect to the flat surface as described above, for example, the positive electrode and the negative electrode are separators It has been found that these can be realized by adopting a housing method in which an electrode group having at least three positive / negative opposing surfaces opposing each other through an electrode. Also, according to this storage method, the method of assembling the battery excluding the electrodes is similar to the method of manufacturing a flat battery using the conventional tablet-shaped electrodes, and a part of the conventional production equipment can be diverted, and the productivity and cost are reduced. It is also excellent in practical use and is preferable in mass production.

Next, a method of actually preparing and storing an electrode group is as follows. A positive electrode plate and a negative electrode plate provided with a current-carrying part in a part of the electrodes are prepared, and the positive electrode plate and the negative electrode plate are laminated via a separator. After the current-carrying portions of the positive electrode plate are exposed from one direction of the separator and the current-carrying portions of the negative electrode plate are exposed from the opposite electrode direction, the positive electrode is connected to the positive electrode, and the negative electrode is connected to the negative electrode. A method is preferred in which the electrodes are electrically connected by a method to form an electrode group and housed in a battery. By arranging the current-carrying parts of the positive and negative electrodes on the opposite electrode, even in a small flat non-aqueous electrolyte secondary battery such as a coin type or button type,
Internal short-circuit due to contact between the positive and negative electrode conducting parts can be prevented.

Next, a description will be given of a method of connecting the electrode group to a battery metal case which also serves as an external terminal. As described above, in the case of a relatively large lithium ion secondary battery such as a cylinder or prism, a tab terminal is welded to the center or the core of the electrode group, and then bent and welded to the safety element or sealing pin. We are collecting electricity. However, the bending process itself is inferior in productivity due to the complexity of the process itself, and it is necessary to provide a space in the battery or to insert an insulating plate between the battery and the electrode group in order to prevent an internal short circuit. Also, when stress is applied to the part where the tab terminal is welded to the electrode, the separator breaks through, or the electrode is deformed, so it is protected with insulating tape,
It was necessary to provide a space in the winding core, and the internal volume of the battery could not be used effectively. For this reason, these current collecting methods cannot be applied to a coin-shaped or button-shaped flat non-aqueous electrolyte secondary battery having a small internal volume of the battery, and a new current collecting method has to be devised.

Therefore, the present inventors exposed a conductive positive electrode constituent material at one end in the direction parallel to the flat surface of the flat battery in the electrode group, and provided a conductive negative electrode constituent material at the other end of the counter electrode. The present inventors have found that an electrode group having an exposed shape is produced, and that each of the electrode components is brought into contact with the positive and negative electrode battery cases to ensure current collection between the electrode group and the battery case. According to this method, it is not necessary to provide a useless space or an insulating plate between the electrode group and the battery case, and the discharge capacity can be increased. In addition, there is no short circuit between the battery case or the electrode and the tab terminal, and the safety and reliability are excellent.

In a flat battery having a sealed structure as in the present invention, stress is applied in a direction perpendicular to the flat surfaces of the negative electrode case and the positive electrode case by caulking of the battery case. And a uniform pressing force is applied in the plane direction of the electrode group, and charging and discharging can be performed smoothly. In addition, the contact between the electrode component exposed portion of the electrode group and the electrode case may be in direct contact, or may be indirectly electrically in contact via a metal foil, a metal net, a metal powder, a carbon filler, a conductive paint, or the like. May be.

Next, as for the electrodes, for the positive and negative electrodes, a conventional method of molding a granular mixture or a method of filling the mixture into a metal substrate such as a metal net or foamed nickel may be used. From the viewpoint of ease, a slurry mixture is preferably applied to a metal foil and dried, and a rolled product can also be used. When using an electrode in which a mixture layer containing an active substance is applied to a metal foil as described above, the electrode used inside the electrode group is formed by forming an active substance layer on both sides of the metal foil. Preferred from the point of efficiency,
Although the active material layer may be used for the exposed portions of the electrode members that come into contact with the battery case at both ends of the electrode group, it is preferable to expose the metal foil among the electrode components in order to reduce the contact resistance. In this regard, an electrode having an active substance layer formed only on one side may be used only for this portion, or an active substance layer may be formed on both sides, and then the active substance layer may be removed only on one side.

On the other hand, the battery of the present invention mainly focuses on the structure of the battery including the electrodes, and there is no limitation on the positive electrode active substance, and MnO ₂ , V ₂ O ₅ , Nb ₂
O ₅ , LiTi ₂ O ₄ , Li ₄ Ti ₅ O ₁₂ , LiFe ₂
O ₄ , LiMn ₂ O ₄ , Li ₄ Mn ₅ O ₁₂ , Li _0.33 M
Metal oxides such as nO ₂ , lithium cobaltate, lithium nickelate and lithium manganate, or inorganic compounds such as graphite fluoride and FeS ₂ , or organic compounds such as polyaniline and polyacene structures are all applicable. . However, the operating potential is high in this,
Lithium cobalt oxide in that it has excellent cycle characteristics,
Lithium nickel oxide, lithium manganate, a mixture thereof, and a lithium-containing oxide in which a part of these elements are substituted with another metal element are more preferable, and the flat nonaqueous electrolyte which may be used for a long time is more preferable. In a secondary battery, lithium cobalt oxide is more preferable because it has a high capacity, has low reactivity with an electrolytic solution or moisture, and is chemically stable.

The negative electrode active material of the battery of the present invention is not limited, and may be metallic lithium or L.
i-Al, Li-In, Li-Sn, Li-Si, Li
Lithium alloys such as -Ge, Li-Bi, Li-Pb,
Alternatively, an organic compound such as a polyacene structure, or a carbonaceous material capable of occluding and releasing lithium, or Nb
Oxides such as ₂ O ₅ , LiTi ₂ O ₄ , Li ₄ Ti ₅ O ₁₂ , Li-containing silicon oxide and Li-containing tin oxide, Li ₃
Any material such as a nitride such as N can be applied, but a carbonaceous material capable of occluding and releasing Li is preferable in terms of excellent cycle characteristics, low operating potential, and high capacity. natural graphite and artificial graphite in that also decreases the cell operating voltage is low, the expanded graphite, mesophase pitch fired, carbonaceous spacing of d _002, such as mesophase pitch fibers fired body is less graphite structure 0.338nm developed Materials are more preferred.

In the above-described battery of the present invention, a flat battery having a long outermost diameter with respect to the total battery height, such as a coin shape or a button shape, has been described. However, the battery of the present invention is not limited thereto. Instead, the present invention can be applied to a flat battery having a special shape such as an oval shape or a rectangular shape, similarly to the present invention.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention and comparative examples will be described in detail. (Embodiment 1) A method of manufacturing a battery according to Embodiment 1 of the present invention is shown in FIG.
This will be described with reference to the sectional view of FIG.

First, with respect to 100 parts by weight of LiCoO ₂ ,
5 parts by weight of acetylene black and graphite powder 5 as conductive agents
Then, 5 parts by weight of polyvinylidene fluoride was added as a binder, and the mixture was diluted and mixed with N-methylpyrrolidone to obtain a slurry-like positive electrode mixture. Next, this positive electrode mixture is applied to one side of a 0.02 mm thick aluminum foil as the positive electrode current collector 2a by a doctor blade method and dried to form a positive electrode active substance containing layer 2b on the aluminum foil surface. did. Thereafter, coating and drying were repeated until the coating thickness of the active substance-containing layer reached 0.39 mm, to produce a single-side coated positive electrode. next,
The coating thickness of the positive electrode active substance-containing layer was 0.39 m per side on both sides of the aluminum foil in the same manner as for the single-side coated positive electrode.
m to form a positive electrode.

Next, styrene-butadiene rubber (SBR) and carboxymethylcellulose (CMC) were used as binders in 100 parts by weight of the graphitized mesophase pitch carbon fiber powder.
Are added by 2.5 parts by weight, and diluted with ion-exchanged water.
The mixture was mixed to obtain a slurry-like negative electrode mixture. This negative electrode mixture is repeatedly applied and dried on a 0.02 mm-thick copper foil as the negative electrode current collector 4 a in the same manner as in the case of the positive electrode such that the thickness of the active substance-containing layer 4 b is 0.39 mm. Then, a single-sided coated negative electrode was produced. Next, a double-sided coated negative electrode was prepared in the same manner as the single-sided coated negative electrode such that the coating thickness of the negative electrode active substance-containing layer was 0.39 mm per side on both surfaces of the copper foil.

These electrodes are 13 mm wide and 13 mm long.
Cut out into a shape with a 6 mm wide and 2 mm long overhang on one side of the square, then peel off the active substance-containing layer formed on this overhang, and expose the aluminum or copper layer as an energized layer. 13mm, length 13mm
A double-sided and single-sided coated positive electrode plate and negative electrode plate on which the active substance-containing layer was formed were prepared.

Then, the current-carrying part of the double-sided coated negative electrode plate is opposed to the previous positive electrode plate via a separator 3 made of a 25 μm-thick microporous polyethylene film at the portion where the positive electrode active material-containing layer of the single-side coated positive electrode plate is formed. Position, and further, a separator coated with a double-sided coated positive electrode plate is disposed so that the current-carrying part faces in the same direction as the previous positive electrode plate. The current-carrying part of the one-side coated negative electrode plate was placed so as to be in contact with the previous negative electrode plate so that 4b was in contact with the negative electrode plate.

After the produced electrode group was dried at 85 ° C. for 12 hours, the opening diameter was 20 mm and the opening area was 3.14 cm ^2.
Negative electrode metal case 5 with integrated insulating gasket 6
The uncoated side of the one-side coated negative electrode plate of the electrode group (that is, the negative electrode current collector 4a) is arranged so as to be in contact with the inner bottom surface of the electrode group, and ethylene carbonate and methyl ethyl carbonate are mixed at a volume ratio of 1:
LiPF ₆ was added as a supporting salt to a solvent mixed at a ratio of 1
Inject a non-aqueous electrolyte dissolved at a rate of mol / l,
Further, the positive electrode case 1 made of stainless steel was fitted so as to be in contact with the uncoated side (that is, the positive electrode current collector 2a) of the single-side coated positive electrode plate of the electrode group, and after turning upside down, caulking was performed on the positive electrode case. Then, the flat nonaqueous electrolyte secondary battery of Example 1 having a thickness of 3 mm and a diameter of φ24.5 mm was sealed. The number of the positive and negative electrode facing surfaces via the separator of this battery was three in total, and the total area of the positive and negative electrode facing surfaces was 5.1 cm ² .

Example 2 The coating thickness of the active substance-containing layer per one side of the positive electrode and the negative electrode in the electrode group was 0.2
A battery was produced in the same manner as in Example 1, except that the number of layers of the double-sided coated positive electrode and the double-sided coated negative electrode in the middle of the electrode group was 2 mm, respectively. The total number of the positive and negative electrode facing surfaces via the separator of this battery was five, and the total area of the positive and negative electrode facing surfaces was 8.5 cm ² .

Example 3 The coating thickness of the active substance-containing layer per one side of the positive electrode and the negative electrode in the electrode group was 0.1, respectively.
A battery was produced in the same manner as in Example 1, except that the number of laminated layers of the double-sided coated positive electrode and the double-sided coated negative electrode in the middle of the electrode group was 3 mm, respectively. The total number of the positive and negative electrode facing surfaces via the separator of this battery was seven, and the total area of the positive and negative electrode facing surfaces was 11.8 cm ² .

Example 4 The coating thickness of the active substance-containing layer per one side of the positive electrode and the negative electrode in the electrode group was 0.1, respectively.
A battery was produced in the same manner as in Example 1, except that the number of layers of the double-sided coated positive electrode and the double-sided coated negative electrode in the middle of the electrode group was 4 mm, respectively. The number of the positive and negative electrode facing surfaces via the separator of this battery was nine in total, and the total area of the positive and negative electrode facing surfaces was 15.2 cm ² .

Comparative Example 1 5 parts by weight of acetylene black and 5 parts by weight of graphite powder were added as conductive agents to 100 parts by weight of LiCoO _2, and 5 parts by weight of polytetrafluoroethylene were added as a binder. The mixture was pulverized to obtain a granular positive electrode mixture. Next, this positive electrode granule mixture was subjected to pressure molding to a diameter of 19 mm and a thickness of 1.15 mm to obtain a positive electrode tablet.

Next, 2.5 parts by weight of styrene-butadiene rubber (SBR) and carboxymethylcellulose (CMC) were added as binders to 100 parts by weight of the graphitized mesophase pitch carbon fiber powder, mixed, dried, and further pulverized. A granular negative electrode mixture was obtained. This negative electrode granule mixture was pressure-formed to a diameter of 19 mm and a thickness of 1.15 mm to obtain a negative electrode tablet.

Next, these positive and negative electrode tablets were heated at 85 ° C.
After drying for 12 hours, a negative electrode tablet, a 0.2 mm thick polypropylene non-woven fabric made of polypropylene, and a positive electrode tablet are placed in this order on a negative electrode case in which an insulating gasket having an opening area of 3.14 cm ² is integrated, and ethylene carbonate and methyl ethyl carbonate are placed. 1 mol of LiPF ₆ as a supporting salt in a solvent obtained by mixing at a volume ratio of 1: 1
/ L of a non-aqueous electrolyte dissolved at a rate of 1 / l, further fitted with a stainless steel positive electrode case, and turned upside down. Then, the positive electrode case was crimped to a thickness of 3 mm and a diameter of φ2.
A 4.5 mm flat nonaqueous electrolyte secondary battery of Comparative Example 1 was produced. The number of the positive and negative electrode facing surfaces via the separator of this battery was one, and the total area of the positive and negative electrode facing surfaces was 2.8 c.
m ² .

Comparative Example 2 A battery was prepared in the same manner as in Example 1 except that the positive electrode and the negative electrode in the electrode group were only single-sided coated electrodes, and the thickness of the active substance-containing layer was 1.24 mm. Was prepared. The number of positive and negative electrode facing surfaces via the separator of this battery was one in total, and the total area of the positive and negative electrode facing surfaces was 1.7 cm ² .

With respect to the batteries of the present example and the comparative example manufactured as described above, a constant current and a constant voltage of 4.2 V and 3 mA were used.
h The first charge was performed. Then, at a constant current of 30 mA, 3.
Discharge was performed to 0 V, and a heavy load discharge capacity was determined. Table 1 shows the results.

[0037]

[Table 1]

As is clear from Table 1, in each battery of this example, the facing area of the positive and negative electrodes using the tablet-shaped electrode prepared by the conventional granule mixture molding method of Comparative Example 1 was larger than the opening area of the gasket. Also, the battery having only a small opposing surface of the positive and negative electrodes of Comparative Example 2 and the battery having a small opposing area has a remarkably large discharge capacity at heavy load discharge.

In the embodiments of the present invention, a flat non-aqueous solvent secondary battery using a non-aqueous solvent as a non-aqueous electrolyte has been described. However, a polymer secondary battery using a polymer electrolyte as a non-aqueous electrolyte has been described. Of course, the present invention is also applicable to a solid electrolyte secondary battery using a solid electrolyte and a polymer thin film or a solid electrolyte membrane can be used instead of a resin separator. Although the shape of the battery has been described based on the coin-shaped non-aqueous electrolyte sealed by crimping of the positive electrode case, it is also possible to replace the positive and negative electrodes and seal by crimping of the negative electrode case. Further, the shape of the battery does not need to be a perfect circle, and the present invention can be applied to a flat nonaqueous electrolyte secondary battery having a special shape such as an oval shape or a square shape.

[0040]

As described above, according to the present invention,
The flat battery has a small battery size, and while maintaining the advantages of excellent productivity, the discharge capacity during heavy load discharge can be significantly larger than that of conventional batteries. A flat nonaqueous electrolyte secondary battery can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a battery according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a battery of Comparative Example 1.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Positive electrode case, 2 ... Positive electrode, 2a ... Positive electrode collector, 2b ...
Positive electrode active substance containing layer, 3 ... separator, 4 ... negative electrode, 4a
... negative electrode current collector, 4b ... negative electrode active material containing layer, 5 ... negative electrode case, 6 ... insulating gasket.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazuo Udagawa 3-4-10 Minamishinagawa, Shinagawa-ku, Tokyo Inside Toshiba Battery Corporation (72) Inventor Masaki Shikoda 3-4-1-10 Minamishinagawa, Shinagawa-ku, Tokyo Toshiba Battery Corporation (72) Inventor Kiyoto Yoda 3-4-10 Minamishinagawa, Shinagawa-ku, Tokyo Toshiba Battery Corporation F-term (reference) 5H029 AJ03 AJ05 AK01 AK02 AK03 AK05 AK07 AK16 AL01 AL02 AL03 AL06 AL07 AL12 BJ02 BJ03 BJ12 CJ02 CJ05 CJ08 CJ22 DJ02 DJ03 DJ04 DJ05 DJ07 HJ07 HJ13

Claims (12)

[Claims] 1. A metal negative electrode case also serving as a negative electrode terminal and a metal positive electrode case also serving as a positive electrode terminal are fitted via an insulating gasket, and the positive electrode case or the negative electrode case is caulked by caulking. A power generating element including an electrode group in which at least a positive electrode and a negative electrode are opposed to each other with a separator interposed therebetween, and a flat non-aqueous electrolyte secondary battery including a non-aqueous electrolyte therein, wherein the electrode group A flat non-aqueous electrolyte secondary battery, wherein the positive and negative electrode facing areas are larger than the opening area of the insulating gasket. 2. The flat nonaqueous electrolyte secondary battery according to claim 1, wherein an electrode group having at least three positive and negative electrode facing surfaces in which a positive electrode and a negative electrode face each other with a separator interposed therebetween is housed in the battery. 3. A positive electrode and a negative electrode are laminated in a multilayer with a separator interposed therebetween, and the positive electrode is connected to the positive electrode and the negative electrode is connected to the negative electrode. 2. The flat nonaqueous electrolyte secondary battery according to 1. 4. A positive electrode plate and a negative electrode plate provided with a current-carrying part in a part of an electrode, and a current-carrying part of the positive electrode plate is exposed from one direction of the separator when the positive electrode plate and the negative electrode plate are laminated with a separator interposed therebetween. The current-carrying portion of the negative electrode plate is laminated so that the current-carrying portion of the negative electrode plate is exposed from the counter electrode direction. The positive electrode is electrically connected to each of the current-carrying portions of the positive electrode and the negative electrode of the negative electrode to form an electrode group. 2. The device according to claim 1, wherein the device is disposed at the opposite pole.
The flat nonaqueous electrolyte secondary battery according to the above. 5. A positive electrode component having conductivity is exposed from at least one positive electrode, a separator, and an electrode group including a negative electrode on one outer surface in a direction horizontal to a flat surface of a flat battery, and the positive electrode component is directly Or electrically connected to the positive electrode case, and expose the negative electrode component having conductivity on the other outer surface in the direction parallel to the flat surface of the flat battery of the electrode group,
The flat nonaqueous electrolyte secondary battery according to claim 1, wherein the negative electrode component is directly or electrically connected to the negative electrode case. 6. The flat nonaqueous electrolyte secondary battery according to claim 1, wherein the positive electrode is an electrode obtained by applying a slurry-type positive electrode mixture containing at least a positive electrode active substance to a metal foil and drying the mixture. 7. The flat nonaqueous electrolyte secondary battery according to claim 1, wherein the negative electrode is an electrode obtained by applying a slurry of a negative electrode mixture containing at least a negative electrode active substance to a metal foil and drying the mixture. 8. The positive electrode and the negative electrode have active substance-containing layers formed on both surfaces of a metal foil, and the active substance layer is not previously coated on a surface directly or electrically contacted with a metal case, or 2. The flat nonaqueous electrolyte secondary battery according to claim 1, having a structure removed after coating. 9. The flat nonaqueous electrolyte secondary battery according to claim 1, wherein the positive electrode active substance is a lithium-containing oxide. 10. The flat non-aqueous electrolyte secondary battery according to claim 9, wherein the positive electrode active substance is lithium cobalt oxide. 11. The flat non-aqueous electrolyte secondary battery according to claim 1, wherein the negative electrode active substance is a carbonaceous material. 12. anode agents flat-shaped non-aqueous electrolyte secondary battery according to claim 1, wherein spacing of d ₀₀₂ plane is a carbon material of less 0.338 nm.