JP2001325926A - Manufacturing method of battery with laminated sheet as outer package case - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an effective mass production with a simple automatic assembling machine securely peeling off an adhesive side of a laminated sheet at an accurate position, without using even partly resin film with low softening point, whenever and environment of a battery in use is in an abnormal state. SOLUTION: The manufacturing method of the battery comprises a molding process of providing a recessed groove 10 communicating with a storage room of a power generating element on the adhesive surface 4 of a first laminated sheet 1A, a first adhering process for heat adhering the adhesive surface 4 of the first laminated sheet and a second laminated sheet 1B without adhering the recessed groove 10 on the adhesive surface 4 of the second laminated sheet 1B, and a sealing process for heat adhering the inner face of the recessed groove 10 on the adhesive surface 4 of the second laminated sheet 1B. Further, the inner face of the recessed groove 10 of the first laminated sheet 1A is adhered to the adhesive surface 4 of the second laminated sheet 1B at an adhesive strength smaller than to the adhesive face other than that of the recessed groove 10, in the manufacturing method of the battery.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a battery using a laminate sheet as an outer case, and more particularly to a method of manufacturing a battery having a safety valve provided in a part of the outer case.

[0002]

2. Description of the Related Art When a battery is overcharged or a large current flows, gas is generated inside the battery and the internal pressure sometimes becomes abnormally high. The abnormally increased internal pressure breaks the laminate sheet and causes damage to the device equipped with the battery. In order to solve this problem, the battery is provided with a safety valve. The safety valve is opened when the internal pressure of the battery increases, thereby preventing damage to the laminate sheet. When the safety valve is opened, gas etc. is discharged to the outside,
Decrease internal pressure. The opened safety valve may discharge the electrolyte and the like together with the gas. The safety valve is disposed in a specific portion and discharges gas, electrolyte, and the like to a predetermined portion.
The device has a structure that does not fail due to gas or electrolyte leaking from the safety valve, for example, a structure in which leaking gas or electrolyte is separated from built-in electronic components by a partition or the like and discharged. Therefore, even if the safety valve is opened, the device will not be damaged.

A battery that realizes this is disclosed in Japanese Patent Application Laid-Open No. 2000-2000.
21368. The battery of this publication uses a resin film with a low softening point for a part of the welding surface,
This part realizes the function of the safety valve. When the battery is used in a state where the internal pressure is increased, the temperature is also increased.
When the internal pressure of the battery rises and the temperature rises, the resin film having a low softening point is softened and melted, and the welding of the laminate sheet is peeled off. That is, the safety valve is opened to prevent the internal pressure from rising.

[0004]

Therefore, this battery can be used safely by preventing an abnormal increase in internal pressure.
However, a battery with this structure requires a resin film with a low softening point to be sandwiched in a specific part of the welded surface of the two-layer laminate sheet, which takes time and effort to manufacture, and the automatic assembly machine Disadvantageously complicates the structure of the device. Further, if a resin film having a low softening point cannot be pinched at an accurate position, it becomes impossible to peel off the welded surface of the laminate sheet at a determined accurate position when the battery temperature increases. There is also a disadvantage that the temperature at which the laminate sheet peels cannot be accurately specified.

[0005] The present invention has been developed for the purpose of solving such a drawback. An important object of the present invention is to manufacture a battery using a laminated sheet that can be safely used as an outer case by reliably peeling off the welding surface of the laminated sheet at an accurate position when the use environment of the battery becomes abnormal. It is to provide a method.

Another important object of the present invention is to provide a battery having an outer case made of a laminate sheet which can be efficiently mass-produced by a simple automatic assembler without partially using a resin film having a low softening point. It is to provide a manufacturing method.

[0007]

According to the present invention, there is provided a method of manufacturing a battery comprising a laminate sheet and an outer case, comprising the steps of disposing a power generation element 2 between a first laminate sheet 1A and a second laminate sheet 1B, The sheet 1A and the second laminate sheet 1B are thermally welded on the welding surface 4 around the power generation element 2, and the power generation element 2 is housed inside the first laminate sheet 1A and the second laminate sheet 1B.

In the method for producing a battery according to the present invention, a forming step of providing a concave groove 10 communicating with the storage chamber 3 of the power generating element 2 on the welding surface 4 of the first laminate sheet 1A; The power generating element 2 is disposed between the first laminated sheet 1A and the second laminated sheet 1B, and the first grooved sheet 10 is not welded to the welding surface 4 of the second laminated sheet 1B. A first welding step of thermally welding the welding surface 4 of the laminate sheet 1B;
And a sealing step of thermally welding the inner surface of No. 0 to the welding surface 4 of the second laminate sheet 1B. Furthermore, in the battery manufacturing method of the present invention, the inner surface of the concave groove 10 of the first laminate sheet 1A is welded to the welding surface 4 of the second laminate sheet 1B with a lower adhesive strength than the welding surface 4 other than the concave groove 10. .

The method for producing a battery according to the present invention preferably comprises
In the first welding step, the first laminate sheet 1A and the second laminate sheet 1B are thermally welded at a higher temperature than the sealing step, and the inner surface of the concave groove 10 of the first laminate sheet 1A is welded to the welding surface 4 other than the concave groove 10. Lower adhesive strength.

Furthermore, in the battery manufacturing method of the present invention, in the sealing step, the first laminate sheet 1A and the second laminate sheet 1B are pressed and thermally welded at a lower pressure than in the first welding step to form the first laminate sheet. The inner surface of the concave groove 10 of the sheet 1A may have a weaker adhesive strength than the welding surface 4 other than the concave groove 10.

Further, the method for manufacturing a battery according to the present invention comprises:
Laminated sheet 1A and second laminated sheet 1B,
It can also be composed of one continuous laminate sheet. This manufacturing method includes the first laminated sheet 1A and the second laminated sheet 1A.
The laminate sheet 1B and the laminate sheet 1B are folded back so that the power generation element 2 is disposed between the first laminate sheet 1A and the second laminate sheet 1B.

[0012]

The laminated sheet manufactured by the method of the present invention and the battery used as the outer case are used in an abnormal state, and when the internal pressure of the battery increases, the concave groove formed in the welding surface 4 of the first laminated sheet 1A. The welded portion is peeled off at the portion of No. 10. In this state, the gas or the like whose internal pressure has been increased is discharged to the outside, thereby preventing the laminate sheet as the exterior sheet from being broken. First laminate sheet 1
The reason why the welding surface 4 of A is peeled off at the portion where the concave groove 10 is provided is that the inner surface of the concave groove 10 is welded to the second laminate sheet 1B with lower adhesive strength than other portions. .

[0013]

Embodiments of the present invention will be described below with reference to the drawings. However, the following examples illustrate a battery manufacturing method for embodying the technical idea of the present invention, and the present invention does not specify the battery manufacturing method in the following method.

Further, in this specification, in order to make it easy to understand the claims, the numbers corresponding to the members shown in the embodiments will be referred to as “claims” and “ In the column of “means”. However, the members described in the claims are not limited to the members of the embodiments.

FIG. 1 is an exploded perspective view showing a battery having a first laminate sheet 1A and a second laminate sheet 1B as an outer case 1, and a storage chamber between the first laminate sheet 1A and the second laminate sheet 1B. The power generation element 2 is housed in 3. The power generating element 2 has a structure in which a positive electrode plate and a negative electrode plate are laminated with a separator interposed therebetween.
4 are connected. The lead plate 14 is hermetically adhered to the welding surface 4 of the first laminate sheet 1A and the second laminate sheet 1B, and is drawn out.

The present invention is a method for producing a battery comprising a laminate sheet and an outer case, but does not specify the type of battery to be produced. The battery is, for example, a secondary battery such as a lithium polymer secondary battery or a lithium ion secondary battery. The material of the power generation element and the components of the electrolyte differ depending on the type of battery. In the lithium polymer secondary battery, the positive electrode plate is made of lithium manganate or vanadium oxide, and the negative electrode plate is made of graphite-based carbon or a lithium alloy. In a lithium ion secondary battery, a positive electrode plate is made of lithium cobaltate or lithium nickelate, and a negative electrode plate is made of graphite-based carbon or coke-based carbon.

The power generating element 2 is manufactured by spirally stacking a positive electrode plate and a negative electrode plate with a separator interposed therebetween, and thereafter pressing the resultant into a flat shape. However, the power generation element
It can also be manufactured by laminating a plurality of positive electrode plates and negative electrode plates via a separator.

As shown in the enlarged cross-sectional view of FIG. 2, the first laminate sheet 1A and the second laminate sheet 1B have a heat-sealing film 6 bonded to a welding surface 4 on the inner side of a metal foil 5 such as an aluminum foil. Then, a protective film 7 for protecting the metal foil 5 is adhered to the surface side of the metal foil 5. The heat welding film 6 is a thermoplastic resin film that can be welded by heating, for example, a polyethylene film is used.
However, a polypropylene film or the like can be used as the thermoplastic resin film. Further, the thermoplastic resin film is bonded to the metal foil 5 in a single layer, or a plurality of different types of thermoplastic resin films are laminated and bonded to the metal foil.

As the protective film 7, any synthetic resin film capable of protecting the surface of the metal foil 5, for example, a PET film can be used. In the first laminated sheet 1A and the second laminated sheet 1B shown in FIG. 2, the protective film 7 is bonded to the metal layer with a urethane-based connecting member 8.

In the battery shown in FIG. 1, the storage recess 9 is provided only in the first laminate sheet 1A, and the second laminate sheet 1B is made flat. In this battery, since the second laminate sheet 1B has a planar shape, the forming process of the second laminate sheet 1B can be simplified. However, in the manufacturing method of the present invention, as shown in FIG. 3, the storage recess 9 can be provided in both the first laminate sheet 1A and the second laminate sheet 1B. In the battery of this structure, the storage recess 9 of the first laminate sheet 1A can be made shallow by storing a thick power generation element.

In the battery shown in FIGS. 1 and 3, two laminated sheets, a first laminated sheet 1A and a second laminated sheet 1B, are laminated, and a welding surface 4 is formed on four sides around the power generating element 2. The power generation element 2 is housed by welding and providing a storage room 3 therein. However, the manufacturing method of the present invention is the first method.
The laminate sheet and the second laminate sheet need not necessarily be two laminate sheets. As shown in FIGS. 4 and 5, with one continuous laminate sheet,
1st laminated sheet 1A and 2nd laminated sheet 1B
Can also be configured.

In the batteries shown in FIGS. 4 and 5, one laminated sheet is divided into two regions in the middle to form a first laminated sheet 1A and a second laminated sheet 1B. This battery is folded back in a state of being stacked on each other at a boundary portion thereof, and the power generation element 2 is disposed between them. In this battery, the lower sheet in FIG.
The storage recess 9 is provided as A, and the upper sheet is the second laminate sheet 1B. In the battery having this structure, the first laminate sheet 1A is welded by welding three sides around the power generation element 2 without welding the folded portion of the laminate sheet.
And the power generation element 2 can be accommodated inside the second laminate sheet 1B. The battery having this structure has a feature that the outer shape can be reduced.

However, in a battery in which one laminate sheet is folded in the middle and the power generation element is stored therein, the storage recesses may be provided in both the first laminate sheet and the second laminate sheet, or the storage recesses may be provided in both. The storage chamber can be provided inside by welding the periphery in a bag shape without providing the storage chamber.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a specific example in which the concave groove 10 is used for injection of an electrolytic solution will be described in detail. The method in which the concave groove 10 is used for injection of the electrolytic solution has a feature that the welding surface 4 of the laminate sheet can have a function of a safety valve while efficiently injecting the electrolytic solution. However, in the manufacturing method of the present invention, it is not always necessary to use the concave groove for the injection of the electrolytic solution, and the electrolytic solution can be injected by another method. In a battery in which the electrolytic solution is not injected into the concave groove, for example, the welding surfaces on three sides of the power generating element are thermally welded, the power generating element and the electrolytic solution are put in the storage chamber, and then the welding surface on the remaining one side is thermally welded. be able to. This method is based on three sides to be welded first or one to be welded last.
A concave groove is provided on one of the sides to provide the function of a safety valve.

Example 1 The battery shown in FIGS. 1 and 3 is manufactured by the following steps. [Step of Forming First Laminated Sheet] As shown in FIG. 1, a recessed groove 10 is formed on the welding surface 4 of the first laminated sheet 1A and communicates with the storage chamber 3 of the power generating element 2 and extends halfway along the outer peripheral edge. Is provided. The concave groove 10 does not extend to the outer peripheral edge of the welding surface 4. However, the concave groove may be provided to extend to the outer peripheral edge of the welding surface, and the inner surface of the concave groove may be welded to the outer peripheral edge of the welding surface in the step of welding the second laminate sheet to the first laminate sheet.

The first laminate sheet 1 shown in FIGS. 1 and 3
A is formed by providing a storage recess 9 for storing the power generating element 2 and a concave groove 10 so as to communicate with the storage recess 9.
Is provided. After the first laminate sheet 1A is heated, it is vacuum-formed to form a storage recess 9 and a recessed groove 10 in a mold. Alternatively, the heated first laminate sheet 1A is sandwiched by a mold to form the storage recess 9 and the concave groove 10. The storage recess 9 is large enough to fit the power generation element 2,
That is, the power generating element 2 is formed into an inner shape that is slightly larger than the outer shape. In the battery of FIG. 1, the power generation element 2 is placed in the storage recess 9 of the first laminate sheet 1A, and the planar second laminate sheet 1B is welded. Accordingly, the first laminate sheet 1A of this battery forms the storage recess 9 having a depth substantially equal to the thickness of the power generation element 2.

The battery shown in FIG. 3 has a first laminate sheet 1A.
, And a storage recess 9 is provided in the second laminate sheet 1B. Therefore, the first laminate sheet 1A of this battery
Forms the storage recess 9 having a depth of about half the thickness of the power generating element.

In a battery containing a thin power generating element, the inner peripheral portion of the welding surface extends when the outer peripheral welding surface is heat-welded without forming the receiving recess in the first laminate sheet and the second laminate sheet. To provide a storage room inside. According to this manufacturing method, since there is no need to provide a storage recess in the first laminate sheet and the second laminate sheet, mass production can be performed more efficiently.

[Opening Step of Through Hole] A through hole 11 is provided on the welding surface 4 of the second laminate sheet 1B. Through hole 11
Is opened at a position communicating with the concave groove 10 of the first laminate sheet 1A. The through-hole 11 is opened by removing a part of the second laminate sheet 1B as shown in FIGS. 6 and 7, or is opened while leaving a part of the through-hole 11 as shown in FIG. . Through hole 11 which is open leaving a part
Has a feature that foreign substances can be prevented from entering.

[First Welding Step of First Laminated Sheet and Second Laminated Sheet] The power generating element 2 is placed between the first laminated sheet 1A provided with the concave grooves 10 and the second laminated sheet 1B provided with the through holes 11. Then, the first laminate sheet 1A and the second laminate sheet 1B are thermally welded to the welding surfaces 4 thereof. As shown in the cross-sectional view of FIG. 9, the welding surfaces 4 of the first laminate sheet 1A and the second laminate sheet 1B press the outer surfaces of the first laminate sheet 1A and the second laminate sheet 1B with the pressurizing and heating tool 13. And heat welded. In this step, the pressurizing and heating tool 13 is
A groove 13A for guiding the concave groove 10 is provided on the pressing and heating surface so as not to weld the inner surface to the welding surface 4 of the second laminate sheet 1B. Therefore, the first laminated sheet 1A and the second laminated sheet 1B fused in this step
As shown in FIGS. 6 to 8, between the welding surface 4 of the first laminate sheet 1A and the second laminate sheet 1B,
An injection path 12 is formed to communicate with the storage chamber 3 and inject the electrolyte. The injection path 12 is opened to the outside through the through hole 11 of the second laminate sheet 1B.

[Electrolyte Injection Step] The tip of an injection nozzle for inserting an electrolyte is inserted from the through hole 11 into the injection path 12, and the electrolyte is injected into the storage chamber 3 by the injection nozzle. The electrolyte can be injected more quickly by reducing the pressure inside the storage chamber 3.

[Sealing Step] After injecting the electrolytic solution, the first laminate sheet 1A and the second laminate sheet 1B are heated in a pressurized state with a pressurizing and heating tool, so that the inner surface of the concave groove 10 is formed in the second laminate sheet. Heat welding is performed on the welding surface 4 of 1B. In this state, the storage room 3 is hermetically sealed. In this step, the inner surface of the concave groove 10 of the first laminate sheet 1A is welded to the welding surface 4 of the second laminate sheet 1B with a lower adhesive strength than the welding surface 4 other than the concave groove 10. In order to heat-weld the inner surface of the concave groove 10 in this state, the pressing and heating tool 1 that presses and heats the laminate sheet in the first welding step
The temperature of 3 is heated above the sealing step. In other words, the temperature of the pressure heater for heating the first laminate sheet 1A and the second laminate sheet 1B in a pressurized state in the sealing step is set lower than in the first welding step.

In the sealing step, the pressure at which the pressing and heating tool sandwiches the first laminated sheet 1A and the second laminated sheet 1B is set lower than that in the first welding step, so that the concave groove of the first laminated sheet 1A is formed. The inner surface 10 can also be welded to the second laminate sheet 1B with a lower adhesive strength than other portions.

Further, in the first welding step and the sealing step, the pressure and the temperature at which the pressing and heating tool sandwiches the first laminated sheet 1A and the second laminated sheet 1B are made the same,
The inner surface of the concave groove 10 can be welded with lower bonding strength than the other welding surfaces 4. That is, the inner surface of the concave groove 10
This is because heat welding is performed only in the sealing step, and the welding surface 4 other than the inner surface of the concave groove 10 can be more reliably heat-welded by heating and pressing with a pressure heating tool in both the first welding step and the sealing step. .

[Embodiment 2] In the manufacturing method of Embodiment 1 described above, the second laminate sheet 1B provided with the through holes 11 is heat-welded to the first laminate sheet 1A.
Can be opened after the first laminate sheet 1A and the second laminate sheet 1B are heat-sealed. This manufacturing method manufactures a battery as follows.

[Process of Forming First Laminated Sheet] Same as in Example 1.

[First Welding Step of First Laminate Sheet and Second Laminate Sheet] Using the second laminate sheet 1B having no through hole, as in Example 1,
1st laminated sheet 1A and 2nd laminated sheet 1B
Is welded by heat. Also in this step, the inner surface of the concave groove 10 is not welded to the welding surface 4 of the second laminate sheet 1B. In the first laminated sheet 1A and the second laminated sheet 1B welded in this step, an injection path 12 communicating with the storage chamber 3 is formed between the welding surfaces 4 of the first laminated sheet 1A and the second laminated sheet 1B. However,
Since the injection path 12 does not have a through-hole opened in the second laminate sheet 1B, it is not communicated with the outside.

[Step of Opening Through Holes] The second laminate sheet 1B laminated on the first laminate sheet 1A is cut to provide through holes 11. The blade provided with the through-hole 11 can be used in the second lamination without cutting the first laminate sheet 1A.
Cut only the laminate sheet 1B. The through hole 11 is
The opening is provided at a position communicating with the concave groove 10 provided in the first laminate sheet 1A. As in the first embodiment, the through-hole 11 is also opened by removing a part of the second laminate sheet 1B as shown in FIG. 6, or as shown in FIG. Open, leaving the part.

Thereafter, a battery is manufactured in the same manner as in Example 1 except for the [injection step of electrolyte solution] and the [sealing step].

[Embodiment 3] The manufacturing method of the above embodiment is as follows.
Although the first laminate sheet and the second laminate sheet are two laminate sheets, the first laminate sheet and the second laminate sheet may be formed of one continuous laminate sheet as shown in FIG. . This manufacturing method manufactures a battery as follows.

[Step of Forming First Laminated Sheet] A single continuous laminated sheet is divided into two regions at the center, one region being a first laminated sheet 1A and the other being a second laminated sheet 1B. On the welding surface 4 of the first laminate sheet 1A, there is provided a concave groove 10 which communicates with the storage chamber 3 of the power generation element 2 and extends halfway along the outer peripheral edge.
The concave groove 10 does not extend to the outer peripheral edge of the welding surface 4. In the first laminated sheet 1A shown in the figure, a concave groove 10 is provided on the welding surface 4 located at a position facing a bent portion where the second laminated sheet is folded. However, the concave groove is the first
It can also be provided on the welding surface at a position adjacent to the bent portion of the laminate sheet and the second laminate sheet.

The laminate sheet shown in FIG. 4 has a recess 9 for accommodating the power generation element 2 formed in the first laminate sheet 1A on the half surface, and a concave groove 10 provided to communicate with the recess 9. The storage recess 9 and the recessed groove 10 are
The molding can be performed in the same manner as in the first embodiment. Although not shown, the battery may be provided with storage recesses in both the first laminate sheet and the second laminate sheet. Furthermore, the battery is formed by heat-welding the outer welding surfaces of the first laminate sheet and the second laminate, which are bent and laminated to each other, without forming a storage recess in the first laminate sheet and the second laminate sheet. It is also possible to provide a storage room in the room.

[Step of Opening Through Hole] Same as in the first embodiment.

[First Welding Step of First Laminated Sheet and Second Laminated Sheet] As shown by the arrow in FIG. 4, one laminated sheet is placed at the boundary between the first laminated sheet 1A and the second laminated sheet 1B. Turn over and stack. At this time, the power generation element 2 is set between the first laminate sheet 1A and the second laminate sheet 1B. The welding surfaces 4 of the first laminate sheet 1A and the second laminate sheet 1B are thermally welded. The laminated sheet, which is folded in two, is located around the power generating element, and excluding the bent portion.
At the sides, the welding surfaces 4 of the first laminate sheet 1A and the second laminate sheet 1B are thermally welded. The welding surfaces 4 of the first laminate sheet 1A and the second laminate sheet 1B are thermally welded in the same manner as in the first embodiment. In this process,
The inner surface of the concave groove 10 is not welded to the welding surface 4 of the second laminate sheet 1B. As shown in FIG. 5, the first laminated sheet 1A and the second laminated sheet 1B welded in this step are communicated with the storage chamber 3 between the welding surfaces 4 of the first laminated sheet 1A and the second laminated sheet 1B. Injection channel 12 is formed. The injection path 12 is opened to the outside through the through hole 11 of the second laminate sheet 1B.

Thereafter, a battery is manufactured in the same manner as in Example 1 except that the [injection step of electrolyte solution] and the [sealing step] are performed.

In this embodiment, after forming a concave groove in the first laminate sheet and opening a through hole in the second laminate sheet, the first laminate sheet and the second laminate sheet are welded on the welding surface. However, the through holes provided in the second laminate sheet can be opened after the first laminate sheet and the second laminate sheet are welded, as in the second embodiment.

In the batteries manufactured in Examples 1 to 3, when the internal pressure becomes abnormally high, the inner surface of the first laminated sheet 1A provided with the concave grooves 10 is peeled off from the second laminated sheet 1B, and the concave grooves are formed. At 10, the state becomes the same as that of the injection path 12, and the injection path 12 is communicated with the outside through the through hole 11, and exhausts gas and the like to the outside.

[Embodiment 4] As shown in FIG. 10, the battery manufactured in the above embodiment is a first laminate sheet 1A.
And the welding surface 4 of the second laminate sheet 1 </ b> B
It can also be cut inside. When the internal pressure becomes abnormally high, the battery of this embodiment has the first laminated sheet 1
The inner surface of the concave groove 10 of A is peeled off from the second laminate sheet 1B, and gas or the like is exhausted to the outside.

[0049]

The method for manufacturing a battery according to the present invention has a feature that, when the environment in which the battery is used becomes abnormal, the welding surface of the laminate sheet can be reliably peeled off at an accurate position and used safely. That is, in the battery manufacturing method of the present invention, the power generation element is housed inside by welding the welding surfaces of the first laminate sheet and the second laminate sheet, and the power generation element is attached to the welding surface of the first laminate sheet. A concave groove communicating with the storage chamber is provided, and the welding surfaces of the first laminate sheet and the second laminate sheet are thermally welded without welding the concave groove to the welding surface of the second laminate sheet. This is because the inner surface of the concave groove is welded to the welding surface of the second laminate sheet with a lower adhesive strength than the welding surface other than the concave groove. When the battery manufactured by the manufacturing method of the present invention is used in an abnormal state and the internal pressure of the battery increases, the welded portion is peeled off at the concave groove portion welded with a weak adhesive strength to increase the internal pressure. Gas and the like can be reliably discharged to the outside. For this reason, it is possible to reliably prevent the laminate sheet, which is the exterior sheet, from being broken by an increase in the internal pressure and to safely use the laminate sheet.

Furthermore, the method for manufacturing a battery according to the present invention does not use a resin film having a low softening point as a part as in the prior art, so that the welding surface of the laminate sheet can be reliably peeled off at an accurate position. Regardless, there is also a feature that the mass production can be efficiently performed by a simple automatic assembling machine and the battery manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a battery manufactured by a manufacturing method according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a laminate sheet of the battery shown in FIG.

FIG. 3 is a perspective view of a battery according to another embodiment of the present invention.

FIG. 4 is an exploded perspective view of a battery manufactured by a manufacturing method according to another embodiment of the present invention.

5 is a vertical sectional view of the battery shown in FIG.

FIG. 6 is a vertical sectional view of a battery according to an embodiment of the present invention.

7 is a sectional view of the battery shown in FIG. 6 taken along the line AA.

FIG. 8 is a vertical sectional view of a battery according to another embodiment of the present invention.

FIG. 9 is a cross-sectional view showing a first welding step of the battery manufacturing method according to the embodiment of the present invention.

FIG. 10 is a perspective view showing a cutting step of a battery manufacturing method according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Outer case 1A ... 1st laminated sheet 1B ... 2nd laminated sheet 2 ... Power generation element 3 ... Storage room 4 ... Welding surface 5 ... Metal foil 6 ... Heat welding film 7 ... Protective film 8 ... Connection material 9 ... Storage recess 10 ... concave groove 11 ... through hole 12 ... injection path 13 ... pressurizing and heating tool 13A ... groove 14 ... lead plate

Claims (4)

[Claims] 1. A power generating element (2) is disposed between a first laminate sheet (1A) and a second laminate sheet (1B), and the first laminate sheet (1A) and the second laminate sheet (1B) are A laminate sheet and an outer case, which are heat-welded on the welding surface (4) around the power generation element (2) and house the power generation element (2) inside the first laminate sheet (1A) and the second laminate sheet (1B). In the method for manufacturing a battery, a power generation element (2) is provided on the welding surface (4) of the first laminate sheet (1A).
Forming a concave groove (10) communicating with the storage chamber (3) of the first laminate sheet (1A) having the concave groove (10);
The power generating element (2) is disposed between the second laminate sheets (1B), and the concave grooves (10) are formed on the welding surface of the second laminate sheet (1B).
(1) a first welding step of heat-welding the welding surfaces (4) of the first laminate sheet (1A) and the second laminate sheet (1B) without welding to the inner surface of the concave groove (10); Welding surface of laminated sheet (1B)
(4) The first laminating sheet (1A) is formed by sealing the inner surface of the concave groove (10) with a lower adhesive strength than the welding surface (4) other than the concave groove (10). (2) A method of manufacturing a laminate sheet to be welded to the welding surface (4) of the laminate sheet (1B) and an outer case. 2. The first laminating sheet (1A) and the second laminating sheet (1B) in the first welding step at a higher temperature than the sealing step.
2. A method for producing a battery comprising the laminate sheet according to claim 1 and an outer case. 3. The method according to claim 1, wherein the sealing step comprises lowering the first laminated sheet (1A) and the second laminated sheet (1A) at a lower pressure than in the first welding step.
2. The method for producing a battery comprising a laminate sheet and an outer case according to claim 1, wherein B) is pressed and thermally welded. 4. The first laminate sheet (1A) and the second laminate sheet (1B) are constituted by one continuous laminate sheet, and the first laminate sheet (1A) and the second laminate sheet (1B) 2. The laminate sheet according to claim 1, wherein a power generation element (2) is disposed between the first laminate sheet (1A) and the second laminate sheet (1B). Battery manufacturing method.