JPH1186823A - Nonaqueous flat battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonaqueous flat battery having higher safety as compared to a battery with a safety valve of conventional structure. SOLUTION: This battery housing a flat electrochemical reaction element 1 between laminating films 3a, 3b and provided with electric terminals 2a, 2b projected from a sealing part 5 sealing the laminating films, is provided with a sealing part 5a formed of bonded parts 6a and 6b and having pressure resistant performance (peeling strength) lower than that of a sealing part 5b at a suitable position of the sealing part 5 which is different from a position, where the electric terminals are arranged. The sealing part 5a is so arranged as to cross perpendicularly to an end surfaces of the laminating films 3a and 3b, since the bonded parts 6a and 6b are peeled off to form a gas-releasing opening 7 releasing gas at a lowpressure when internal pressure of this battery increases, the rupture of the laminating films can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-aqueous flat battery, and more particularly, to a structure of a safety valve thereof.

[0002]

2. Description of the Related Art Conventionally, a sealed battery is provided with a safety valve that operates when the gas pressure inside the battery rises and discharges gas outside the battery. Examples thereof are shown in FIGS.

A water-based flat battery 51 shown in the perspective view of FIG.
In Japanese Unexamined Patent Publication (Kokai) No. 61-116752, an unsealed portion is provided at an end face of a sealing portion 52 using a laminate film, and this portion is used as a safety valve 53 for degassing. In FIG. 13, reference numeral 54 denotes a jacket, 55 denotes an electrode group, and 56 and 57 denote leads.

[0004] A non-aqueous prismatic battery 61 (Japanese Patent Laid-Open No. 5-314959) shown in FIG. 14 is one in which a safety valve is provided on the flat bottom surface of a rectangular can. 14A is a plan view of the battery, FIG. 14B is a cross-sectional view taken along line HH of FIG. 14A, and FIG. 14C is a cross-sectional view taken along line JJ of FIG. In this battery, a part of the battery container has a multilayer structure in which two metal plates 62 and 63 are bonded to each other, and a through hole 64 is formed in the metal plate 63 to make the part thinner than the other parts and torn. The configuration is such that the portion functions as the safety valve 65 by making it easier. In FIGS. 14A to 14C, 66
Is a lid body, 67 is a sealing glass, and 68 is an electrode pin.

FIG. 15 shows a non-aqueous flat battery 71 (Japanese Unexamined Patent Application Publication No.
FIG. 1 is a plan view of a battery according to the present invention, in which a lower terminal plate is not attached, as viewed from below.
This battery is a thin battery in which terminal plates serving also as current collectors are arranged above and below a power generating element, and the peripheral edges of these terminal plates are sealed with an electrically insulating sealing member 72.
The bonding strength between the terminal plate 2 and the terminal plate is partially reduced, and this portion is used as a safety valve.

That is, in this battery, the periphery of the upper and lower terminal plates, which are both current collectors and exterior members of the power generation element, are sealed, and the adhesive strength thereof is locally reduced. Temperature of fusion / sealing by thermoplastic resin,
The pressure is changed at a predetermined portion to lower the adhesive strength as compared with other portions. Further, in another embodiment, the sealing width of the sealing portion is reduced at the predetermined portion 73 to lower the adhesive strength. In FIG. 15, reference numeral 74 denotes a positive electrode active material, and 75 denotes an electrolyte.

[0007]

However, in the case of a non-aqueous flat type battery, since the water entering from outside the exterior member adversely affects the battery characteristics, the battery 5 shown in FIG.
It is not possible to use a safety valve structure that is always in communication with the outside as in 1. Further, it is difficult to use the battery 61 of FIG. 14 as a flat battery due to its structure. Further, the pressure resistance of the metal plate 63 is likely to be high, and in the case of a non-aqueous flat battery using a laminate film having a low pressure resistance as an exterior member, it is difficult to stably lower the pressure resistance of the safety valve.

Further, there is a problem in the safety valve of the battery 71 shown in FIG. Hereinafter, this will be described. There are various types of so-called bond strengths, and there are three general types: shear strength, tensile bond strength, and peel strength. However, if one of these strengths is increased, the other strength decreases. A phenomenon occurs.

For example, epoxy resin, which is one of the most common adhesives, has an increased elastic modulus with the progress of curing, and a large shear strength can be obtained with this. And then rapidly decreases with increasing elastic modulus. Also, in general,
As the thickness of the adhesive increases, the shear strength decreases, but the peel strength increases (with some exceptions). For this reason, when considering the adhesive strength, it is necessary to specifically specify the type as the shear strength, the tensile adhesive strength, or the peel strength [Adhesion Handbook (2nd edition) pp. 5
4-55: The editor is the Japan Adhesion Association, and the publisher is the Nikkan Kogyo Shimbun.

[0010] In the battery 71 shown in FIG.
Since the sealing width (adhesion width W) of 2) is reduced at a predetermined portion to surely lower the adhesion strength, the above-mentioned Japanese Patent Application Laid-Open No.
Specifically, the adhesive strength used in the specification of JP-A-13061 is a shear strength and a tensile adhesive strength, and is not considered to be a peel strength. This is because the peel strength has no direct relation to the width of the sealing portion in the peel direction.

FIG. 16 shows a peeling state of a sealing portion having a small width in the peeling direction as shown in FIG.
FIG. 4 is a plan view of a sealing portion. (B) and (d) show K- of (a).
FIG. 9 is a cross-sectional view taken along the line K, where (d) shows a state in which peeling has progressed from (b). (C) and (e) are cross-sectional views taken along line LL of (a), and (e) shows a state in which peeling has progressed from (c). When the internal pressure of the battery increases, the same gas pressure acts on both the non-sealing portion 81 and the sealing portion 82. This pressure causes the upper and lower terminal plates to expand due to the force applied to the upper and lower terminal members also serving as the exterior member, and at the same time, a peeling force acts on the sealing portion 82 in the vertical direction. The battery has a square shape of, for example, 4 cm × 4 cm and the pressure is 10
kg / cm ² , the force is 4 × 4 × 10 = 1
60 kg, and this force is received on four sides of 4 × 4 cm. Therefore, in order to prevent the sealing portion 82 from peeling off,
The peel strength is 10 kg / cm. In addition, 91 and 92 are exterior members.

In FIG. 15, since the overall shape of the sealing portion is square, the above-mentioned force is biased, but is applied almost evenly to the surrounding sealing portions. At this time, since the periphery of the non-sealing portion 81 is sealed, this force is received by the sealing portion, and is not directly applied. A relatively small force, based on the correspondingly applied force, is applied to the sealing portion 82 adjacent to the non-sealing portion 81.
However, peeling of a portion having a small width in the peeling direction does not occur first. Of course, in a test in which only the sealing portion 82 is pulled, for example, the portion having a small width in the peeling direction has a low tensile adhesive strength, so that the portion starts to be damaged. There is no.

After that, when the entire peeling has progressed to a position where the non-sealing portion 81 disappears, the peeling proceeds on the entire surface. Since the sealing portion 82 is damaged by the peeling as described above, the width W of the sealing portion 82 in the peeling direction (FIG. 15)
Even if the shear strength and the tensile bond strength are reduced by means such as reducing the size, the sealing portion 82 is damaged from this portion. Therefore, when the pressure inside the battery increases, it cannot be expected that the gas will be reliably released from this portion.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a non-aqueous flat battery having higher safety than a battery having a safety valve having a conventional structure.

[0015]

According to a first aspect of the present invention, there is provided a non-aqueous flat type battery in which a flat electrochemical reaction element is housed in an exterior member, and electric energy or electricity generated from the electrochemical reaction element is stored. An electrical terminal for outputting target information to the outside of the exterior member is provided at an appropriate position, a sealing portion having a film structure is provided on a part of the exterior member, and at least a part of the sealing portion or the surface of the exterior member is provided. A sealing means having a lower pressure resistance than other sealing portions.

That is, according to the present invention, in a flat battery having a non-aqueous completely sealed type film structure sealing structure, a film structure sealing portion is provided on a part of an exterior member, and at least a part of the sealing portion is provided. Alternatively, by providing a sealing means having a lower pressure resistance performance than that of the part of the outer member on the outer member surface, the sealed part of the outer member having a film structure acts as a safety valve in response to an increase in pressure inside the battery, By preferentially breaking at a lower pressure than that of the other parts of the member, it is possible to prevent the exterior member itself having the film structure from exploding due to the damage.

According to a second aspect of the present invention, there is provided a non-aqueous flat battery according to the first aspect, wherein the sealing means is provided in a shape crossing the sealing portion in a direction perpendicular to an end face of the exterior member. I do.

According to a third aspect of the present invention, in the non-aqueous flat battery, the sealing means is provided in a part of the sealing portion on the side of an electrochemical reaction element in the sealing portion, and the sealing means is provided. The length of the means in the direction parallel to the end surface of the exterior member is larger than the entire length of the sealing portion in the direction perpendicular to the end surface of the exterior member, and the length in the direction perpendicular to the end surface of the exterior member is set to The length of the stop is smaller than the length in the vertical direction.

According to a fourth aspect of the present invention, there is provided the non-aqueous flat battery according to the first aspect, wherein an opening is formed in at least a part of the exterior member overlapping the electrochemical reaction element, and the sealing member serves as the sealing means. A film-like member for sealing the opening is provided, and the pressure resistance of the sealing portion is lower than that of the other sealing portions.

According to a fifth aspect of the present invention, there is provided a non-aqueous flat battery according to the second or third aspect, wherein the sealing portion is formed by a heat-sealing resin layer or an adhesive layer. It is characterized in that it is formed by making the thickness of the resin coating layer or the adhesive layer smaller than that of other sealing portions.

According to a sixth aspect of the present invention, in the non-aqueous flat battery according to the second or third aspect, the sealing portion is formed by a heat-sealing resin layer or an adhesive layer, and the sealing means has a flat cross section. Further, the other sealing portion is characterized in that its cross section is formed in an uneven shape or a corrugated shape.

According to a seventh aspect of the present invention, in the non-aqueous flat battery according to the second or third aspect, the sealing portion is formed of a heat-sealing resin layer or an adhesive layer. A film material different from the material forming the portion is embedded in the sealing portion and formed.

According to an eighth aspect of the present invention, in the non-aqueous flat battery according to the third aspect, the sealing portion is formed by a heat-sealing resin layer or an adhesive layer, and the sealing means forms the sealing portion. A cylindrical hollow member made of a film material different from the material to be formed is embedded in the sealing portion.

According to a ninth aspect of the present invention, there is provided the non-aqueous flat battery according to the second aspect, wherein the sealing portion is formed by a heat-sealing resin layer or an adhesive layer. The electric terminal is provided in the vicinity, and the sealing means is formed so that the pressure resistance of the sealed portion of the electric terminal is lower than that of other sealed portions.

[0025] The non-aqueous flat battery according to claim 10 is
The electrical terminal according to claim 4, wherein an electrical terminal is provided in a portion of the exterior member overlapping the electrochemical reaction element, and the sealing unit has a pressure resistance of a sealed portion of the electrical terminal lower than other sealing portions. It is characterized by being formed by.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. Example 1 (Claim 1) FIG. 1 shows a battery structure, in which (a) is a plan view of the battery,
(B) is a sectional view taken along line AA of (a). In FIG. 1, an electrochemical reaction element 1 includes a positive electrode, a negative electrode, and an electrolyte. 2a and 2b are electrical terminals, 3a and 3b
Denotes an exterior member (laminated film), and 4 denotes a sealing portion that seals around the exterior member.

The electrodes (not shown) constituting the electrochemical reaction element 1 are each formed by forming an active material layer on a current collector made of metal, and the active material layer faces the electrolytic solution. And the current collector faces the exterior material. There is also a separator (not shown) between the electrodes, which is impregnated with electrolyte. The laminate films 3a and 3b have a multilayer structure. One side of the metal film is covered with a sealing material for sealing, and the other surface exposed to the outside is covered with a thermosetting resin. Hereinafter, the method of manufacturing the battery will be described.

The positive electrode is made of LiCoO ₂ , graphite and P
VDF (polyvinylidene fluoride) in a weight ratio of 90: 7: 3
Was dispersed in NMP (N-methylpyrrolidone), applied to a 20 μm A1 substrate, and dried at 120 ° C. to produce a positive electrode having an active material layer having a thickness of about 100 μm.
The negative electrode was prepared by dispersing glalite and PVDF in NMP at a weight ratio of 90:10, applying this to a 10 μm Cu substrate, drying at 120 ° C., and having an active material layer having a thickness of about 70 μm. And Both the positive electrode and the negative electrode were used after being roll-pressed. As an electrolytic solution, a 1M-LiPF ₆ solution of a mixed solvent of PC (propylene carbonate) and DMC (dimethyl carbonate) was used. A separator having a porosity of 40% or more and a thickness of 25 μm was used.

Examples of the positive electrode active material include, in addition to LiCoO ₂ , oxides with lithium intercalation such as V ₂ O ₅ , LiNiO ₂ , and LiMn ₂ O ₄ , polymer materials such as polyaniline and polypyrrole, and other non-volatile materials. Aqueous secondary battery materials such as a positive electrode material for a secondary battery, a conventional dry battery, an alkaline battery, and a nickel hydride battery can also be used. The graphite mixed with the positive electrode active material may be natural graphite or artificial graphite,
Amorphous carbon may be used. PVDF is used as a binder.
In addition, fluorine-containing NMP-soluble polymers, PVP
(Polyvinylpyrrolidone) and the like can be used.

The negative electrode active material is not limited to natural graphite, but may be artificial graphite or amorphous carbon. As the binder, other than PVDF, a fluorine-containing NMP-soluble polymer, PVP, or the like can be used.

The positive electrode and the negative electrode thus manufactured are punched into a predetermined size, and then the positive electrode is placed on an exposed portion of the current collector formed by not previously coating the active material layer on a part of the positive electrode and the negative electrode. A1, negative electrode is made of Ni and has a thickness of 5
The 0 μm terminals were ultrasonically welded, placed in the direction extending to the same side, and laminated with a separator interposed therebetween. This laminate is formed into two laminate films 3a,
3b, the surrounding three sides are heated to 120 ° C., and sealed between the metal plates by heat sealing to form a sealing portion. After the electrolyte is injected, the last one side is formed. The corresponding terminal side portion was sealed by heat fusion to form the sealing portion 4.

In the first embodiment, a stacked paper battery using one positive electrode and one negative electrode is used. However, a stacked multi-layer battery provided with a plurality of positive electrodes and a plurality of negative electrodes may be used. In this case, the terminal, the positive electrode, and the negative electrode are electrically connected by ultrasonic waves, spot welding, or the like.

As the electrolyte constituting the above electrolyte, cyclic carbonate or chain carbonate which is a carbonate ester is used, but non-aqueous electrolyte such as carboxylate ester, acetonitrile, dimethylformamide, dimethylsulfoxide and the like may be used. If the battery is not a non-aqueous secondary battery, water may be used. The supporting salt is LiBF ₄ , L
iClO ₄ , LiAsF ₆ , LiSO ₃ CF ₃ , LiC
(SO ₂ CF ₃ ) ₃ , LiN (SO ₂ CF ₃ ) _{2 and the} like can also be used. Further, a polymer such as polyacrylonitrile, polyethylene oxide, or polyvinyl copolymer containing the above electrolyte may be used. When a polymer is used, the separator need not be used.

The above laminated film has a thickness of 25 μm.
The inside of the aluminum of m, that is, the surface on the electrode side is coated with polyethylene as a fusing material, and the outside on the other side is coated with polyester. Instead of polyethylene, a polyolefin such as polypropylene, a modified polyolefin containing a carboxyl group, or an ionomer can be used as the coating material.A hot melt resin may be used as an adhesive layer, or an epoxy resin adhesive layer. May be provided only in the sealing portion. For the outer coating, polyimide, polyamide, polyphenylene oxide, or the like may be used, or the same polyolefin-based fusing material as the inner coating may be used.

Instead of using a laminate film, at least one may be a hard case and the case may be sealed with a fusing material or an adhesive. The film structure of the sealing portion may be sufficiently thin as compared with the thickness of the electrode of the exterior member, and may be formed by fusing or bonding. The external appearance may not be a film.

The strength of the film itself of the laminated film of Example 1 is determined by the material and thickness of the base material such as aluminum, the thickness of the fusion material coated on the inside and its thickness, and the thickness of the protection material coated on the outside and its thickness , And the adhesive between them, but the strength is compared with a thick plate of 0.1 mm or more made of stainless steel, aluminum or iron material used for conventional cylindrical, square and other batteries. Target small. For this reason, the rupture due to the increase in the internal pressure of the battery occurs at a lower pressure than that of a rectangular battery or the like. Further, since the battery is a flat type battery, the members also need to be flat and thin, and it is difficult to manufacture a safety valve having such a mechanism.

In this embodiment, the periphery of the laminate film as the exterior member is sealed by heat sealing to seal the exterior member, but the pressure resistance of the sealing is lower than the pressure resistance of the laminate film itself. With the sealed configuration, the rupture due to the increase in the pressure inside the battery does not occur in the laminate film itself, and the heat-sealed sealing portion around the laminate film first occurs at a relatively low pressure. The sealing portion can act as a safety element that releases the generated gas to the outside of the battery and reduces the pressure inside the battery.

As described above, for example, a size of 4 cm
× 4 cm square battery, the pressure is 10 kg / cm ²
, The above force is 4 × 4 × 10 = 160 kg, and this force is received on four sides of 4 × 4 cm, so that the force for peeling is 10 kg / cm. This force is biased because the shape of the entire sealing portion is square, but is applied to the surrounding sealing portions almost equally. In this case, by coating 25 μm thick aluminum with polyethylene and polyester having a thickness of 100 μm or less, the tensile strength of the laminated film itself is increased to 15 kg / cm (the thickness is corrected and the width of the film is measured in cm units). Notation) or more can be easily achieved.

At this time, if the laminate film is sealed so that the pressure resistance of the sealing portion becomes 5 kg / cm, the sealing portion is peeled off when the internal pressure of the battery becomes 5 kg / cm or more. Then, the internal gas is released, and the sealing portion itself functions as a safety element, and it is possible to prevent the laminate film from bursting at a high pressure due to an increase in the pressure inside the battery.

In order to make the pressure resistance of the sealing portion lower than the pressure resistance of the laminate film itself, the peel strength of the sealing portion should be 5 or less.
kg / cm.
What is necessary is just to change the heating conditions or pressurizing conditions at the time of sealing.
In addition, since the sealing portion is provided from the beginning, the thickness of the battery can be maintained.

Example 2 (Claim 2) FIGS. 2A and 2B show the structure and operation of a battery, wherein FIG. 2A is a plan view of the battery, and FIG. 2B is a sectional view taken along line BB of FIG.
(C) is a cross-sectional view taken along the line BB of (a) similarly to (b), and shows a state at the time of gas release inside the battery. In FIG. 2, reference numeral 5 denotes a sealing portion, and a part of the sealing portion, that is, the sealing portion 5a has a lower pressure resistance than the other sealing portions 5b, and is provided on the end surfaces of the exterior members 3a and 3b. The sealing portion 5a is provided in a shape crossing the vertical direction.
Can be easily formed by changing the material, molecular weight, adhesive material, and the like of the fusing material (differing from other parts).

In this embodiment, the gas release due to the increase in the pressure inside the battery can be performed at a low pressure only by lowering the peel strength at a part of the sealing portion 5, and the leakage of the sealing portion can be prevented. Alternatively, it is possible to prevent the laminate films 3a, 3b from being ruptured at high pressure only by forming a minimum partial peel strength reduction portion while maintaining high reliability as a gas barrier. That is, the bonding portions 6a and 6b shown in FIG. 2B have the shape shown in FIG. 2C, and the gas is released by forming the gas discharge port 7.

FIGS. 3A and 3B are explanatory views of the peeling state of the sealing portion 5a of FIG. 2, and FIG. 3A is a plan view of the sealing portion 5. FIG. (B)
(D) is a cross-sectional view taken along the line CC of (a), showing the progress of the peeling. When the pressure in the battery increases, the same gas pressure is applied to both the normal sealing portion 5b and the sealing portion 5a having a low pressure resistance (low peeling strength). When this pressure causes the upper and lower laminated films to expand. At the same time, a force for peeling off the sealing portion 5 acts in the vertical direction (the thickness direction of the laminate film).
Since the sealing portion 5 is rectangular (see FIG. 2A), the magnitude of this force differs between the corner portion of the sealing portion 5 and each side portion. In parts, they are almost even.

At this time, breakage due to peeling starts first in the sealing portion 5a having low peel strength. After this, the sealing portion 5
Although the peeling of a progresses to some extent, since the normal sealing portion 5b around the sealing portion 5a has high peeling strength and remains unpeeled, the laminate films 3a and 3b around FIG. In FIG. 3B, the vertically swelling portion is a square portion 5c (marked by X in FIG. 3B) substantially determined by the width of the sealing portion 5a, and the force for peeling at this portion is smaller than at the beginning. Become. Therefore, the peel strength of the sealing portion 5a needs to be set to a sufficiently low value so that the peeling continues. Since this sealing portion is provided from the beginning, the thickness of the battery can be maintained.

Example 3 (Claim 3) FIGS. 4A and 4B show the structure and operation of a battery, wherein FIG. 4A is a plan view of the battery, and FIG. 4B is a sectional view taken along line DD of FIG. 3 shows the shape of the sealing portion 5 a having a low peel strength among the sealing portions 5. (C) is a cross-sectional view taken along the line DD of (a) as in (b), and shows a state at the time of gas release inside the battery. In FIG. 3A, reference numeral 5b denotes a sealing portion having normal peel strength. In the sealing portion 5a having a low peel strength, the length in the direction parallel to the end surface of the exterior member is set to be larger than the length in the direction perpendicular to the end surface of the exterior member. Further, the sealing portion 5a is not formed over the entire width of the exterior member, but starts on the electrochemical reaction element 1 side and ends in the width direction of the exterior member. The sealing portion 5a is made of the material of the fusion material, the molecular weight, the material of the adhesive, and the like.
It can be formed by making it different from b.

In this embodiment, the laminate films 3a,
3b, adhesive portions 6a and 6b forming a sealing portion 5a
However, as shown in FIG. 4 (c), when the pressure inside the battery is increased, the gas can be released at a low pressure by swelling up and down due to peeling. As described above, in the present embodiment, by only partially lowering the peel strength, it is possible to prevent the liquid film from leaking under a high pressure while maintaining a high liquid barrier function and a high gas barrier function required for the sealing portion. can do. Further, since the sealing portion 5b having a normal peel strength is formed without a break around the sealing portion 5a, the reliability of the sealing portion can be kept very high.

FIGS. 5A and 5B are explanatory views of the peeling state of the present embodiment, and FIG. 5A is a plan view of the sealing portion 5. FIG. (B) ~
(E) is a cross-sectional view taken along the line EE of (a), showing the progress of peeling. When the pressure in the battery increases, the same gas pressure acts on both the normal sealing portion 5b and the sealing portion 5a having a small pressure resistance. This pressure causes the upper and lower laminate films 3a and 3b to expand, and at the same time, a peeling force acts on the sealing portion 5a in the vertical direction. Although this force is biased because the sealing portion 5 is rectangular, it is applied to the surrounding sealing portions almost evenly. At this time, breakage due to peeling starts in the sealing portion 5a. Thereafter, the peeling proceeds to just before the usual sealing portion 5b.

Since the peel strength of the sealing portion 5b is higher than that of the sealing portion 5a, the progress of the peeling may be stopped here. However, the sealing strength of the sealing portion 5b is slightly lowered and the sealing portion 5a 5 is set higher than that of FIG.
From (d) to the state of (e), the sealing portions 5a,
5b is in the form shown in FIG. 4 (c) (gas release port 7 is formed), and gas is released. The reason for this is that, although empirical, when peeling proceeds, peeling in the same direction tends to occur. That is,
If the peeling starts with a force smaller than the peeling force required for the normal sealing portion 5b, the normal sealing portion can be peeled off with a low peeling force. This is similar to the fact that if the corner is first peeled off with an adhesive tape or the like, the rest becomes easier to peel off.

Of course, similar to the sealing portion of the second embodiment, the surrounding normal sealing portion 5b has a high peeling strength and remains unpeeled from the beginning. The area of the portion where the laminate film swells up and down becomes substantially smaller. Therefore, the sealing portion 5a has a length in the direction parallel to the end surface of the exterior member, which is larger than the entire length of the sealing portion in a direction perpendicular to the end surface of the exterior member.
It must be formed with a sufficient width. Since this sealing portion is provided from the beginning, the thickness of the battery can be maintained.

Embodiment 4 (Claim 4) FIGS. 6A and 6B show the structure and operation of a battery, wherein FIG. 6A is a plan view of the battery, FIG. 6B is a sectional view taken along line FF of FIG. (c) is a cross-sectional view taken along line FF of (a), similar to (b), showing a state when gas is released from the inside of the battery. In FIG. 6, reference numeral 3c denotes an opening formed in the exterior member 3a, and reference numeral 11 denotes a sealing portion for sealing the opening 3c. The sealing portion 11 is made of a film-like member 12 different from the exterior member 3a, and is bonded to the exterior member 3a and has a lower pressure resistance than the exterior member 3a. That is, the adhesive force of the film member 12 to the exterior member 3a is lower than the adhesive force of the exterior member 3a to the electrochemical reaction element 1.

Therefore, when the pressure in the battery increases, the sealing portion 11 easily peels off as shown in FIG. 6C, and the gas in the battery is discharged to the outside through the opening 3c. The sealing portion 11 can be formed by changing the material, molecular weight, adhesive material, or the like of the fusing agent. In the present embodiment, by providing a new sealing portion on the laminate film separately from the surrounding sealing portion, the liquid leakage prevention function required for the sealing portion and the reliability of the gas barrier function were maintained at a high level. As it is, rupture of the laminate film at high pressure can be prevented. Since the thickness of the new sealing portion is substantially the same as that of the laminate film, the battery can be kept thin.

Embodiment 5 (Claim 5) FIG. 7 is a sectional view showing the structure of a sealed portion of a battery. In this embodiment, the entirety of the sealing portion 13 is formed by a heat-sealing resin layer or an adhesive layer, and the sealing portion 13a having a reduced pressure resistance is formed by the thickness of the heat-sealing resin layer or the adhesive layer. Is made smaller than those of the other parts. That is, by making the thickness of the heat-sealing resin layer or the adhesive layer smaller than that of the other sealing portions, the sealing portions 13a
The peel strength can be reduced even if the shear strength and the tensile bond strength of the rubber are increased. As a result, the sealing portion 13a having a lower pressure resistance performance than the other portions has the same fusing material,
It can be formed using the same molecular weight, the same adhesive material, or the like. The thickness of the heat-sealing resin layer or the like can be reduced by pressing a predetermined portion of the laminated film on which a normal sealing portion is to be formed with the convex portion of a heated mold having a convex shape. It is.

Embodiment 6 (Claim 6) FIG. 8 is a sectional view showing the structure of a sealed portion of a battery. The sealing portions 14 and 14a are formed of a heat-sealing resin or an adhesive, and the cross section of the sealing portion 14a is made flat.
By increasing the withstand voltage performance by forming a concave / convex shape or a corrugated shape 4, as a result, the withstand voltage performance (peel strength) of the sealing portion 14 a is lower than that of the sealing portion 14. By doing so, it is possible to form the sealing portion 14a having a lower pressure resistance than the other portions by using the same material of the fusion material, the same molecular weight, the same material of the adhesive, and the like.

In order to form the sealing portions 14 and 14a in this embodiment, a predetermined portion of the laminate film for forming a normal sealing portion is pressed and pressed by a mold having flat portions and uneven portions. All you have to do is heat it up. The sealing portion 14a is formed by the flat portion, and the sealing portion 14 is formed by the uneven portion. Although the sealing portion 14a is flat in FIG. 8, the sealing portion 14a is made uneven, and the uneven shape is changed to the sealing portion 14a.
By making the shape different from the concave and convex shape, the pressure resistance performance of the sealing portion 14a can be lowered. In addition, these uneven shapes may be either parallel or perpendicular to the end face of the sealing portion,
It is also effective in a dot shape or a mesh shape.

Embodiment 7 (Claim 7) FIG. 9 is a sectional view showing the structure of a sealed portion of a battery. In this embodiment, the sealing portion 15 is formed of a heat-sealing resin or an adhesive, and another film member 16 is embedded in the sealing portion 15. That is, since the adhesive strength of the contact surface between the upper and lower surfaces of the film member 16 and the sealing portion 15 is lower than the adhesive strength between the laminated films 3a and 3b and the sealing portion 15, the film member 16 has lower pressure resistance. A sealing portion can be formed. As the film member 16,
Teflon, imide-based films, etc., which have better thermal stability than the heat-sealing resin layer or whose adhesive strength (peeling strength) with the sealing portion 15 is small as described above, are particularly suitable. A nylon film may be used.

In this embodiment, the peel strength between the film and the heat-fusible resin layer (or the adhesive layer) can be easily reduced by sandwiching the film between the heat-fusible resin layers or the adhesive layers. This makes it possible to form a sealing portion having a lower pressure resistance than the other portions by using the same material, molecular weight, adhesive material and the like of the fusion bonding material. In order to embed the film member 16 in the sealing portion 15, it is possible to easily form the laminate film 3a, 3b or the like simply by pressing and heating the laminated film 3a, 3b or the like with a mold having a convex portion.

Embodiment 8 (Claim 8) FIG. 10 is a sectional view showing the structure of a sealed portion of a battery. In this embodiment, a sealing portion 17 having a normal peel strength is formed by a heat-sealing resin or an adhesive, and the sealing portion 17 has a different thickness from the heat-sealing resin or the adhesive. Has a structure in which a tubular hollow film member 18 sufficiently thinner than the sealing portion 17 is crushed and embedded. Reference numeral 18a denotes a contact surface between the inner peripheral surfaces of the hollow film member 18, and the contact surfaces are merely in contact with each other. The contact surface 18a is set lower than the stop portion 17.
Is easily peeled off by a low-pressure gas to form a gas outlet. The film member having the tubular structure needs to have better thermal stability in the case of heat fusion than the fusion resin layer, but when an adhesive is used, the peel strength may be large or small.

In this embodiment, since the cylindrical film member is hollow and the contact surface between the film members is easily separated, the peel strength at the contact surface portion can be easily reduced. . Therefore, a sealing portion having a smaller pressure resistance performance than the other portions can be formed by using the same material, molecular weight, adhesive material, or the like of the sealing material. Also,
For sealing, it is only necessary to pressurize and heat with the same mold and conditions as before. However, since the inside of the tubular structure is hollow, it does not have the gas barrier properties, liquid leakage prevention properties, and the like required for the sealing portion, and therefore the shape crossing the sealing portion described in the embodiment of claim 2. Cannot be used for

Embodiment 9 (Claim 9) FIGS. 11A and 11B show the structure and operation of a battery. FIG. 11A is a plan view of the battery, and FIG. 11B is a sectional view taken along line GG of FIG.
(C) is a sectional view taken along the line GG of (a) as in (b), and shows a state when gas is released from the inside of the battery. In this embodiment, electrical terminals 2a and 2b are provided on a sealing portion 4 at the end face of the exterior member 3a and a sealing portion 19 having a lower peel strength than the sealing portion 4, respectively. Reference numerals 20a and 20b are bonding portions. The sealing portion 19 having a shape crossing the sealing portion 4 having normal peel strength and having a low pressure resistance can be manufactured by changing the material, molecular weight, adhesive material, and the like of the fusion bonding material, As shown in the embodiments of the fifth, sixth and seventh aspects, it can also be manufactured by changing the shape of the sealing and the like.

Since the sealing portion 19 has electric terminals, the thickness of the fusion resin layer is reduced by utilizing the change in the thickness and heat conduction of the sealing portion 19 or by utilizing the thickness of the terminal. Or using the high thermal conductivity of the terminal metal,
By increasing the heating temperature, the fusion resin layer can be made to flow and the thickness of the fusion resin layer can be reduced. Furthermore, by using a resin such as low-molecular-weight polyethylene having low thermal stability as a material of this portion, a large thermal change due to high temperature can be given, and the peel strength itself can be reduced. Further, by utilizing the step due to the thickness of the terminal, the substantial thickness of the fused resin layer at that portion can be reduced. In this way, by using the terminal portion, it is possible to easily produce a transversely-sealed sealing portion having a lower pressure resistance than other components.

Embodiment 10 (Claim 10) FIG. 12 is a plan view showing the structure of a battery, and 21 is a sealing portion. In this embodiment, the electric terminals 2a and 2b are provided in a form for sealing an opening (not shown) formed in the exterior member 3a in a direction overlapping with the flat electrochemical reaction element 1, and these terminals are further provided. The sealing portion 21 is formed by sealing with a film-like member different from the exterior member 3a. Then, the electric terminals 2a, 2
The portion for sealing b is a sealing portion having low pressure resistance.

When the terminals are provided in the form of a laminate film, a sealing portion is provided for insulation and sealing of the terminal take-out portion, except when using the laminate film itself as a terminal. In the present embodiment, the sealing portion of the terminal is also used as a sealing portion having a low pressure resistance for releasing the gas inside at a low pressure. By changing the peel strength, it is possible to prevent the laminate film from being ruptured while securing the gas barrier properties due to the sealing around the laminate film, the liquid leakage prevention properties, and the like.

[0063]

As apparent from the above description, according to the present invention, the following functions and effects can be obtained. (1) Operation and Effect of Claim 1 In the non-aqueous flat battery according to claim 1, a sealing portion having a film structure is provided on a part of an exterior member that accommodates the electrochemical reaction element, and at least this sealing portion is provided. A sealing means having a lower pressure resistance than other sealing parts is provided on a part or on the surface of the exterior member, so that when the pressure inside the battery increases, the sealing means first peels and breaks, and Is released to the outside of the battery, so that it is possible to appropriately prevent the pressure inside the battery from becoming high and the exterior member (for example, a laminate film) from exploding due to explosion. (2) Operation and Effect of Claims 2 to 10 In the non-aqueous flat battery according to claims 2 to 10, at least a part of the sealing portion of the film structure has a sealing means whose pressure resistance is lower than that of the exterior member. Is provided at a predetermined location and in a predetermined shape and structure, and when the pressure inside the battery increases, the sealing portion first peels and breaks, releasing the gas inside the battery. In addition, it is possible to appropriately prevent the laminated film from exploding due to high pressure due to high pressure, and to enhance the reliability of sealing around the laminated film. Note that the battery of the present invention can be applied as a power source for a mobile phone, a portable arithmetic processing device, or the like, or as a secondary battery integrated with a solar cell.

[Brief description of the drawings]

FIG. 1 shows a battery structure according to Example 1 of the present invention.
(A) is a plan view of a battery, and (b) is a cross-sectional view taken along line AA.

FIG. 2 shows the structure and operation of the battery of Example 2,
(A) is a plan view of a battery, and (b) is a cross-sectional view taken along line BB of (a). (C) is a sectional view showing a state when gas is released from the inside of the battery.

FIGS. 3A and 3B are explanatory diagrams showing a peeling state of a sealing portion of the battery of FIG. 2, wherein FIG. 3A is a plan view of the sealing portion, and FIGS. 3B to 3D are CC lines of FIG. It is sectional drawing and shows the progress of the said peeling.

FIG. 4 shows the structure and operation of the battery of Example 3.
(A) is a plan view of a battery, and (b) is a cross-sectional view taken along line DD of (a). (C) is a sectional view showing a state when gas is released from the inside of the battery.

5A and 5B are explanatory views showing a peeling state of a sealing portion of the battery of FIG. 4, wherein FIG. 5A is a plan view of the sealing portion, and FIGS. 5B to 5E are EE lines of FIG. It is sectional drawing and shows the progress of the said peeling.

FIG. 6 shows the structure and operation of the battery of Example 4,
(A) is a plan view of a battery, and (b) is a cross-sectional view taken along line FF of (a). (C) is a sectional view showing a state when gas is released from the inside of the battery.

FIG. 7 is a cross-sectional view showing a sealed structure of a battery according to a fifth embodiment.

FIG. 8 is a cross-sectional view illustrating a sealed structure of a battery according to a sixth embodiment.

FIG. 9 is a cross-sectional view showing a sealed structure of the battery of Example 7.

FIG. 10 is a sectional view showing a sealed structure of a battery according to an eighth embodiment.

FIG. 11 shows the structure and operation of the battery of Example 9;
(A) is a top view of a battery, (b) is GG sectional drawing of (a). (C) is a sectional view showing a state when gas is released from the inside of the battery.

FIG. 12 is a plan view showing a battery structure of Example 10.

FIG. 13 is a perspective view showing an example of a conventional water-based flat battery.

FIG. 14 relates to an example of a conventional non-aqueous prismatic battery.
(A) is a plan view, (b) is a cross-sectional view taken along line HH of (a),
(C) is a sectional view taken along line JJ of (a).

FIG. 15 is a plan view showing another example of the conventional non-aqueous flat battery and showing a state where a lower terminal plate is removed.

16 (a) and 16 (b) are views for explaining a peeling state of the sealing portion having a small width in the peeling direction shown in FIG. 15, and (a) is a plan view of the sealing portion. (B) and (d) are cross-sectional views taken along the line KK of (a), and (d) shows a state in which peeling has progressed from (b). (C) and (e) are cross-sectional views taken along line LL of (a).
(E) shows a state in which peeling has progressed from (c).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrochemical reaction element 2a, 2b Electrical terminal 3a, 3b Exterior member (laminated film) 3c Opening 4, 5, 5a, 5b Sealing part 5c Square part 6a, 6b Adhesive part 7 Gas outlet 11 Sealing part DESCRIPTION OF SYMBOLS 12 Film-like member 13, 13a, 14, 14a, 15, 17 Sealing part 16 Film member 18 Hollow film member 18a Adhesive surface 19 Sealing part 20a, 20b Adhesive part 21 Sealing part

Claims (10)

[Claims] A flat electrochemical reaction element is housed in an exterior member, and an electric terminal for outputting electric energy or electrical information generated from the electrochemical reaction element to the outside of the exterior member is provided in a proper position. A sealing portion having a film structure is provided on a part of the exterior member, and sealing means having a lower pressure resistance than other sealing portions is provided on at least a part of the sealing portion or on the surface of the exterior member. Non-aqueous flat type battery characterized by the above-mentioned. 2. The non-aqueous flat battery according to claim 1, wherein said sealing means is provided in a shape crossing said sealing portion in a direction perpendicular to an end surface of said exterior member. 3. The sealing means according to claim 1, wherein the sealing means is provided on a part of an inner side of the sealing portion on the side of an electrochemical reaction element, and is provided in a direction parallel to an end face of the exterior member of the sealing means. The length is larger than the entire length of the sealing portion in a direction perpendicular to the end surface of the exterior member, and the length in the direction perpendicular to the end surface of the exterior member is smaller than the length of the sealing portion in the vertical direction. Non-aqueous flat type battery characterized by the above-mentioned. 4. The film-like member according to claim 1, wherein an opening is formed in at least a part of the exterior member overlapping with the electrochemical reaction element, and the sealing means seals the opening. And a pressure-resistant performance of the sealing portion is made lower than that of the other sealing portions. 5. The heat sealing resin layer or the adhesive layer according to claim 2, wherein the sealing portion is formed by a heat sealing resin layer or an adhesive layer. A non-aqueous flat battery formed by making it smaller than other sealing portions. 6. The sealing portion according to claim 2, wherein the sealing portion is formed by a heat-sealing resin layer or an adhesive layer, the sealing means has a flat cross section, and the other sealing portions have an uneven cross section. A non-aqueous flat battery characterized in that it is formed in the shape of a wave or a wave. 7. The sealing part according to claim 2, wherein the sealing part is formed by a heat-sealing resin layer or an adhesive layer, and the sealing means uses a film material different from a material forming the sealing part. A non-aqueous flat battery formed by being buried in the sealing portion. 8. The sealing device according to claim 3, wherein the sealing portion is formed by a heat-sealing resin layer or an adhesive layer,
A non-aqueous flat battery, wherein a tubular hollow member made of a film material different from the material forming the sealing portion is embedded in the sealing portion. 9. The method according to claim 2, wherein the sealing portion is formed of a heat-sealing resin layer or an adhesive layer, and the electrical terminal is provided in a portion of the sealing portion near an end surface of the exterior member. A non-aqueous flat battery, wherein the sealing means is formed such that a pressure resistance of a sealing portion of the electric terminal is lower than other sealing portions. 10. The electrical connector according to claim 4, wherein an electrical terminal is provided in a portion of the exterior member overlapping with the electrochemical reaction element, and the sealing means reduces the pressure resistance of the sealed portion of the electrical terminal. A non-aqueous flat battery, wherein the battery is formed lower than a sealing portion.