JP2000306606A - Manufacture of plate-like polymer battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method capable of mass-producing a highly reliable plate-like polymer battery while reducing the size and weight. SOLUTION: This manufacturing method has a process of forming a cylindrical battery element 3 by winding a tape-like positive electrode and a tape-like negative electrode in a spiral shape via a separator, a process of coaxially inserting/arranging the cylindrical battery element 3 in both end side opening cylindrical enclosing film body 4, a process of forming a plate body 7 by pressurizing opposed side surfaces of the cylindrical enclosing film body 4 for inserting/arranging the battery element 3, a process of airtightly sealing an opening of the enclosing film body 4 except for a one end side opening part of the plate body 7 and a process of sealing/installing the polymer battery element 3 by airtightly sealing the polymer battery element 3 after injecting an electrolyte from the one end side opening part of the plate body 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing a plate-shaped polymer battery.

[0002]

2. Description of the Related Art For example, secondary batteries such as non-aqueous solvent batteries are widely used as power sources for portable telephones and video cameras. In the power supply battery,
With the miniaturization and high performance of the above-mentioned devices, miniaturization, weight reduction, high voltage, high capacity, and the like are required. In response to such a demand, a plate-shaped polymer battery is known (JP-A-3-230474, JP-A-3-225765, etc.).

That is, a plate-shaped battery element is positioned and accommodated in a cylindrical exterior film body (exterior covering body / bag body) having an open end, and the exterior film body is sealed (sealed). To produce a sealed body. Then, after injecting a required electrolyte from the opening, the opening is thermally fused (welded),
BACKGROUND ART A plate-shaped polymer battery having a hermetically sealed configuration is known. In the manufacture of the plate-shaped polymer battery, a wound body in which a tape-shaped positive electrode, a tape-shaped negative electrode, and a tape-shaped separator are spirally (tubularly) formed is pressed to flatten the battery element. In some cases.

Here, the tape-shaped positive electrode is formed mainly of a lithium-containing metal oxide (for example, lithium manganese composite oxide, lithium-containing cobalt oxide) and manganese dioxide which occlude and release lithium ions. . Further, the tape-shaped negative electrode is formed of lithium metal, a carbonaceous material that absorbs and releases lithium, and a lithium alloy. Further, the tape-like separator is a polymer-electrolyte system in which a separator base made of a polypropylene nonwoven fabric or the like is impregnated or supported with an ethylene carbonate solution such as a lithium salt or a non-aqueous electrolyte.

[0005] In the manufacture of the above-mentioned plate-shaped polymer battery, the battery element is formed in a spiral shape, is formed into a plate shape by pressing the opposing side surfaces, and this plate-shaped battery element is mounted and arranged in a cylindrical outer film. In the case of the means, there are advantages that the size and capacity can be easily reduced and that the cost can be reduced.

[0006]

FIG. 3 is a perspective view schematically showing an embodiment of a conventional method for manufacturing a plate-shaped polymer battery, which is performed in the following procedure. First, a cylindrical exterior film body 1 made of a laminated film in which resin layers are provided on both main surfaces of a metal foil and having both ends open is prepared. On the other hand, a cylindrical battery element 2 is prepared by spirally winding a tape-shaped positive electrode and a tape-shaped negative electrode with a separator interposed therebetween, and the side surface of the battery element 2 is pressed into a flat plate. Next, as shown in FIG. 3, the flat battery element 2 is inserted and arranged from one end side (opening) of the cylindrical exterior film body 1. In FIG. 3, reference numeral 1a denotes a welded / cylindrical portion of the exterior film body 1, and reference numerals 2a and 2b denote external lead-out terminals of the battery element 2 having a cylindrical shape.

After that, the opening of the exterior film body 1 except for the one end side opening of the cylindrical exterior film body 1 in which the battery element 2 is inserted and arranged is hermetically sealed, and the electrolytic solution is supplied from one open end side. After the injection, the container is hermetically sealed to seal the polymer battery element.

However, in the cylindrical exterior film body 1,
In inserting and mounting the battery element 2 formed into a plate-like pressure, not only operations such as insertion position alignment are complicated, but also smooth insertion and mounting are difficult, and the exterior film body 1 is likely to be damaged. There is a problem. That is, while productivity or mass productivity is reduced, there are problems such as a decrease in reliability of the plate-shaped polymer battery product and a reduction in manufacturing yield.

In order to solve such a problem, it is conceivable to set the opening to a relatively large size in order to facilitate the insertion and mounting of the plate-shaped battery element 2. However, setting the opening into which the plate-shaped battery element 2 is inserted to be relatively large, on the other hand, increases the size of the exterior film body 1 and consequently reduces the density of the battery element 2 with respect to the exterior film body 1. Therefore, high capacity and miniaturization are impaired.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a manufacturing method capable of mass-producing a highly reliable plate-shaped polymer battery in addition to reducing the size and weight. I do.

[0011]

According to the first aspect of the present invention, a tape-shaped positive electrode and a tape-shaped negative electrode are spirally wound via a separator to form a cylindrical battery element.
A step of coaxially inserting and disposing the cylindrical battery element in a cylindrical exterior film body having both ends opened, and pressurizing opposing side surfaces of the cylindrical exterior film body in which the battery elements are inserted and arranged to form a flat body. And the step of hermetically sealing the opening of the exterior film body except for the opening at one end of the flat body, and hermetically sealing after injecting the electrolyte from the one end opening of the flat body. And a step of sealing the polymer battery element.

According to a second aspect of the present invention, in the method for producing a plate-shaped polymer battery according to the first aspect, the tubular exterior film body is a laminate film having a resin layer on both surfaces of a metal layer. I do.

According to a third aspect of the present invention, a tape-shaped positive electrode and a tape-shaped negative electrode are spirally wound via a separator to form a cylindrical battery element, and both ends of the cylindrical battery element are opened. Inserting and arranging coaxially in the cylindrical exterior film body, and pressing the opposing side surfaces in a state where the fused portion of the cylindrical exterior film body in which the battery elements are inserted and arranged is released, thereby preparing a preliminary plate-like body. And selectively bending the fused portion of the preliminary plate-shaped body exterior film body to form a flat body, and opening the exterior film body excluding the opening at one end side of the flat body. Plate-shaped polymer, comprising: a step of hermetically sealing a portion, and a step of hermetically sealing after injecting an electrolytic solution from one end side opening of the flat body, and sealing a polymer battery element. This is a method for manufacturing a battery.

According to a fourth aspect of the present invention, in the method for producing a plate-shaped polymer battery according to the third aspect, the cylindrical exterior film body is a laminate film having a resin layer provided on both sides of a metal layer. I do.

According to a fifth aspect of the present invention, in the method for manufacturing a plate-shaped polymer battery according to any one of the first to fourth aspects, a pair of guides are used to prevent positional displacement when the opposing side surfaces are pressed. Features.

In the invention of claims 1 to 5,
The battery element is a wound and wound body of a tape-shaped positive electrode and a tape-shaped negative electrode interposed with a tape-shaped electrolyte also serving as a separator for a polymer battery. That is, a tape-shaped positive electrode obtained by laminating an active material such as a metal oxide, a positive electrode containing a non-aqueous electrolyte and an electrolyte-retaining polymer on a current collector, an active material for absorbing and releasing lithium ions, and a non-aqueous electrolyte And a tape-like negative electrode obtained by laminating a negative electrode containing an electrolyte-retaining polymer on a current collector, and a tape-like polymer-electrolyte system (for example, a hexafluoropropylene-vinylidene fluoride copolymer or the like) having an electrolyte functioning as a separator. Ethylene carbonate solution such as polymer and lithium salt… Non-aqueous electrolyte…
And a wound body comprising the above materials.

Here, as an active material of the tape-shaped positive electrode,
For example, lithium manganese composite oxide, manganese dioxide, lithium-containing cobalt oxide, lithium-containing nickel cobalt oxide, lithium-containing amorphous vanadium pentoxide, chalcogen compound and the like can be mentioned. Further, as the active material of the tape-shaped negative electrode, for example, bisphenol resin, polyacrylonitrile, fired products such as cellulose,
Examples include coke and fired pitch products, which may take a form containing natural or artificial graphite, carbon black, acetylene black, Ketjen black, nickel powder, nickel powder, or the like.

Further, the polymer electrolyte system may be used in a non-aqueous solvent such as ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, etc., for example, lithium perchlorate, lithium hexafluorophosphate, boron tetrafluoride, etc. Examples thereof include those in which lithium fluoride, lithium arsenide hexafluoride, lithium trifluoromethanesulfonate, and the like are dissolved at about 0.2 to 2 mol / l.

Examples of the current collector of the tape-shaped positive electrode include aluminum foil, aluminum mesh, aluminum band metal, and punched metal made of aluminum.
Examples include copper foil, copper mesh, copper band metal, and copper punch metal.

In the first to fifth aspects of the present invention,
The cylindrical exterior film body for inserting and mounting the battery element is
Both ends are open, and at least the sealing / fused portion is formed of a heat-fusible resin. That is, it is an open-ended type having an inner diameter and a length that can seal / lead out the respective electrode terminals of the wound / wound body constituting the battery element, and can be entirely sealed. Examples of the film forming the exterior film body include a polyimide resin film, a polyester resin film, a polypropylene resin film, and a laminate type in which resin layers are provided on both sides of a metal layer in consideration of moisture resistance and the like. .

Here, the film material forming the cylindrical exterior film body is formed into a cylindrical exterior film body, or is fused and sealed after injecting the electrolytic solution. It is preferable that a hot-melt adhesive resin layer is interposed, or at least a surface which is in contact with each other and sealed is made of a hot-melt resin layer in advance.

In the first to fifth aspects of the present invention, the inner diameter of the cylindrical exterior film body is adjusted in order to ensure the operability and workability of insertion and mounting and the high density of the battery capacity. It is preferable that the outer diameter is about 0.2 to 1 mm larger than the outer diameter of the wound body. Further, after the cylindrical battery element is inserted and mounted in the cylindrical exterior film body, the opposing side surface is pressed sideways on the flat surface of the support, and the pressing body is placed on the flat surface of the support. It is performed by pressing the flat surface of the support, and at this time, in order to prevent a sideways slippage of a cylindrical battery element placed sideways on the flat surface of the support,
It is desirable to have a guide.

In other words, if a pair of guides is arranged at a required interval on the side surface of a cylindrical battery element placed sideways, the pressurization of the plate is controlled. Pressing and damage of the battery element are avoided, while the thickness is controlled to a constant value. In addition, the disposed guides prevent positional deviation such as side slip when the cylindrical battery element is pressed and damage to the lead terminals to the outside due to the positional deviation, so that reliability and yield are reduced. Improvement is achieved.

Further, when forming into a plate by the above pressure,
When the fused part of the exterior film body is subjected to primary (preliminary) molding on a certain plate-like body in a state where the fused part of the exterior film body is released, and then the fused part of the exterior film body is bent, a higher yield can be obtained with higher reliability. It is possible to manufacture a plate-shaped polymer battery having high performance.

According to the first to fifth aspects of the present invention, in the manufacturing process of the plate-shaped polymer battery, the insertion and attachment of the battery element to the cylindrical exterior film body are easily performed, so that a high-quality plate-shaped polymer battery can be manufactured. Can be manufactured with good yield. That is, since the cylindrical battery element wound body is inserted and mounted on the cylindrical exterior film body, the insertion and mounting work proceeds smoothly.

Further, since the battery element wound body is pressurized and formed into a plate shape after insertion and mounting, the possibility of damaging the outer surface of the battery element wound body is eliminated, and high reliability or high yield is obtained. Sealing with an exterior film body is performed. Therefore, good productivity can be maintained, and a high-quality plate-shaped polymer battery can be provided at low cost.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, FIGS. 1 (a) to 1 (c) and FIG.
Embodiments will be described with reference to (a) to (d).

FIGS. 1A to 1C are perspective views schematically showing the first embodiment. First, a tape-shaped positive electrode, a tape-shaped separator and a tape-shaped negative electrode are wound, and the outer diameter is 22.6.
While a cylindrical polymer battery element 3 having a length of about 50 mm and a length of about 50 mm is manufactured, an inner diameter of about 22.9 mm having both ends open is provided.
A cylindrical exterior film body 4 having a length of about 60 mm is prepared.
Here, the cylindrical polymer battery element 3 has a tape-shaped positive electrode and a tape-shaped negative electrode facing each other, a tape-shaped polymer-electrolyte system interposed and arranged between these two electrodes, and a tape-shaped both electrode, respectively. Electrically in contact with the current collector, and the corresponding lead terminals 3a and 3b are extended (derived) apart from the current collector. In addition, the cylindrical exterior film body 4
Is provided with a polyester resin layer on both sides (both main surfaces) of the aluminum foil and a heat-fusible resin layer (for example, a carboxylic acid-modified polypropylene resin layer) on one side of the polyester resin layer. Made of a laminated film. Then, this cylindrical exterior film body 4 was formed by winding a rectangular laminated film into a cylindrical shape with the heat-fusible resin layer inside, and heat-sealing the edges thereof to form a cylindrical shape. Things.

Next, as shown in FIG. 1 (a), the cylindrical polymer battery element 3 is corresponded and positioned with respect to the one end opening of the cylindrical exterior film body 4. The cylindrical polymer battery element 3 is inserted and mounted in the cylindrical exterior film body 4. afterwards,
As shown in FIG. 1 (b), the cylindrical exterior film body 4 in which the polymer battery element 3 is inserted and mounted is positioned and placed on the flat surface of the support 6, while facing the flat surface of the support 5. Then, the flat plate 7 is arranged, and 10 to 50 kg / cm ²
By applying a certain degree of pressure, the cylindrical polymer battery element 3 and the exterior film body 4 are integrally formed into a plate-like body 8 as shown in FIG.

Next, one end side of the plate-like body 8, in other words, one end opening of the exterior film body 4 (for example, the extension side of the lead terminals 3a, 3b) is hermetically sealed by the interposition of an adhesive or heat fusion. Stop. That is, the exterior film body 4
Is formed in a rectangular bag shape in which the lead terminals 3a and 3b of the polymer battery element 3 are led out in a hermetic sealing type. Thereafter, a required electrolytic solution is injected and filled from the opening at the other end of the bag-shaped exterior film body 4, and then the opening at the other end is hermetically sealed by the interposition of an adhesive or heat fusion. I do. By such a series of steps, a small, high-capacity plate-shaped polymer battery with good yield can be easily obtained.

FIGS. 2A to 2D are perspective views schematically showing the second embodiment.

Production of cylindrical polymer battery element 3, construction of cylindrical exterior film body 4, cylindrical exterior film body 4
The insertion and attachment of the cylindrical polymer battery element 3 to the device were performed in the same manner as in the first embodiment.

Next, as shown in FIG. 2A, the cylindrical exterior film body 4 into which the polymer battery element 3 is inserted and mounted is positioned on a pair of flat surfaces of the support 6 'with the guides 5a. Place. Here, the support 6 'is of a vacuum suction / holding type, and the guide 6a arranged so as to be able to advance and retreat relatively to its flat surface has a height corresponding to the thickness and width to be flattened. And are spaced apart. Then, the cylindrical exterior film body 4 in which the polymer battery element 3 is inserted and mounted is positioned with the fusion portion 4a of the cylindrical exterior film body 4 facing upward between the pair of guides 6a.
Is placed.

Next, the cylindrical outer film body 4 into which the positioned and mounted polymer battery element 3 is inserted and mounted.
A flat plate 7 'having an opening 7a in the region corresponding to the fused portion 4a of the cylindrical exterior film body 4 is placed on the upper surface so as to face and align with each other, as shown in FIG. 7 '
Preforming is performed by applying a pressure of about 5 to 45 kg / cm ² .
In this preforming step, the pair of guides 6a are spaced apart corresponding to the preforming, while the fused portion 4a of the cylindrical exterior film body 4 has the opening 7a of the flat plate 7 'as a relief portion. The cylindrical polymer battery element 3 and the exterior film body 4 are integrally formed into a plate-like body without fear of bending or damage due to the pressure. Thereafter, as shown in FIG. 2C, the welded portion 4a of the cylindrical exterior film body 4 of the preformed shape is selectively pressed by the pusher 5 'to bend the fused portion 4a. FIG.
As shown in (d), the flat plate 7 is arranged facing and aligned, and a pressure of about 10 to 50 kg / cm ² is applied to the flat plate 7,
The plate-like body 7 has required thickness and width dimensions.

Next, one end side of the plate-like body 8, in other words, one end opening of the exterior film body 4 (for example, the extension side of the lead terminals 3a and 3b) is hermetically sealed by the interposition of an adhesive or heat fusion. Stop. That is, the exterior film body 4
Is formed in a rectangular bag shape in which the lead terminals 3a and 3b of the polymer battery element 3 are led out in a hermetic sealing type. Thereafter, a required electrolytic solution is injected and filled from the opening at the other end of the bag-shaped exterior film body 4, and then the opening at the other end is hermetically sealed by the interposition of an adhesive or heat fusion. I do. By such a series of steps, a small, high-capacity plate-shaped polymer battery with good yield can be easily obtained.

In the case of the second embodiment, in the step of forming a plate by pressurization, the rotation of the workpiece is prevented, so that the displacement is avoided, and the welding portion of the exterior film body 4 is welded.
The selective bending of 4a is performed. Therefore, there is an advantage that the displacement of the lead terminal is reliably prevented, and that the defective welding of the welded portion 4a of the exterior film body 4 is eliminated.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the invention. For example, the constituent material of the exterior film body may be changed to another material, or the constituent material of the cylindrical battery element may be changed to another material.

[0038]

According to the first to third aspects of the present invention, a high-quality plate-shaped polymer battery can be provided with a high yield without requiring complicated operations. That is, a cylindrical (wound) battery element is inserted into a cylindrical exterior film body.
After the mounting, the battery is pressurized and plate-shaped, so that the operation of inserting and mounting the battery element into the exterior film body is greatly simplified. Further, the simplification of the insertion / mounting operation not only saves labor in the insertion / mounting operation process, but also greatly contributes to improvement in manufacturing yield and cost reduction.

[Brief description of the drawings]

FIGS. 1A, 1B, and 1C are perspective views schematically showing a first embodiment example in the order of steps.

FIGS. 2A, 2B, 2C and 2D are perspective views schematically showing a second embodiment example in the order of steps.

FIG. 3 is a perspective view schematically showing an embodiment of a manufacturing process of a conventional plate-shaped polymer battery.

[Explanation of symbols]

 1, 4 ... cylindrical exterior film body 1a, 4a ... fused part of cylindrical exterior film body 2, 3 ... cylindrical battery element (winding body) 2a, 4a ... positive electrode lead terminal 2b, 4b ... ... Negative electrode lead terminal 5, 5 '... Pusher 6, 6' ... Support 7, 7 '... Flat plate 7a ... Flat plate opening 8 ... Plate-shaped body

Continued on the front page F term (reference) 5H011 AA06 CC02 CC06 CC10 DD13 EE04 FF02 GG09 HH01 HH13 JJ25 5H029 AJ14 AK02 AK03 AK05 AL06 AL07 AL08 AM03 AM07 BJ04 BJ14 CJ03 CJ13 DJ02 DJ03 DJ11 EJ01 EJ11

Claims (5)

[Claims] 1. A step of spirally winding a tape-shaped positive electrode and a tape-shaped negative electrode via a separator to form a cylindrical battery element, and a cylindrical exterior having both ends open to the cylindrical battery element. A step of coaxially inserting and arranging in the film body; a step of pressing the opposing side surfaces of the cylindrical exterior film body in which the battery elements are inserted and arranged to flatten; and excluding an opening on one end side of the flat body A step of hermetically sealing the opening of the exterior film body, and a step of hermetically sealing after injecting an electrolytic solution from one end side opening of the flat body to seal the polymer battery element. A method for producing a plate-shaped polymer battery. 2. The method for producing a plate-shaped polymer battery according to claim 1, wherein the tubular exterior film body is a laminate film having a resin layer provided on both sides of a metal layer. 3. A step of spirally winding the tape-shaped positive electrode and the tape-shaped negative electrode via a separator to form a cylindrical battery element, and a cylindrical exterior having both ends opened to the cylindrical battery element. A step of inserting and arranging coaxially in the film body, and a step of pressing the opposing side surfaces in a state where the fused portion of the tubular exterior film body in which the battery element is inserted and arranged to escape is formed into a preliminary plate-like body Selectively bending the fused portion of the preliminary plate-shaped exterior film body to form a flat body, and hermetically sealing the opening of the exterior film body except for the opening at one end of the flat body. A method for manufacturing a plate-shaped polymer battery, comprising: a step of shutting down; and a step of injecting an electrolytic solution from an opening on one end side of the flat body, hermetically sealing the battery, and sealing a polymer battery element. 4. The method for producing a plate-shaped polymer battery according to claim 3, wherein the tubular exterior film body is a laminate film having a resin layer provided on both sides of a metal layer. 5. The method for manufacturing a plate-shaped polymer battery according to claim 1, wherein a pair of guides are used to prevent positional displacement when the opposing side surfaces are pressurized.