JPS63119155A - Manufacture of flat cell - Google Patents

Abstract

PURPOSE:To manufacture a flat cell of a constant form and an excellent performance, by sealing a generating unit which consists of a positive electrode mix sheet, a separator, a negative electrode sheet, and the like, and cutting into a specific form by the spray of a superhigh pressure liquid. CONSTITUTION:A generating unit 14 is composed by connecting a positive electrode mix sheet 141, a separator 142, and a negative electrode sheet 143 in this order. The unit 14 is surrounded by a frame-formed insulating sealing substance 12. And a positive electrode terminal plate 11 is attached closely covering the surface of the sheet 141 and one side surface of the sealing substance 12. Then, after the whole cell is sealed up, a spray of a superhigh pressure liquid 164 is applied to the sealing parts between the terminal plates 11 and 15, and the sealing substance 12, and the whole body can be cut off into a desired form.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Field of Application) The present invention relates to a method for manufacturing a flat battery, and more specifically, the present invention relates to a method for manufacturing a flat battery, and more specifically, the present invention relates to a method for manufacturing a flat battery, and more specifically, the present invention relates to a method for manufacturing a flat battery. It prevents misalignment, improves work efficiency during assembly, lowers the cost of batteries, and prevents deterioration of battery sealing performance and short circuits between the positive and negative terminal plates. The present invention relates to a method for manufacturing a flat battery.

(Prior art) In recent years, as electronic devices such as electronic wristwatches and desktop computers have become smaller and thinner, the flat batteries used in these electronic devices have also become smaller and thinner, and their walls have become thinner and smaller. The following flat batteries have been put into practical use.

Conventionally, as such an ultra-thin flat battery, for example, a battery having a structure as disclosed in Japanese Patent Application Laid-open No. 128232/1983 has been known, and this is manufactured as follows. It is common to do so.

That is, in FIG. 7, a positive electrode mixture sheet 31, a separator 33 impregnated with an electrolytic solution, and a negative electrode sheet 32
are laminated in this order to form a power generation unit, and this power generation unit is surrounded by a frame-shaped insulating sealing body 34 cut into a predetermined shape, and between a positive electrode terminal plate 35 and a negative electrode terminal plate 36 which are cut into a predetermined shape. Then, the entire peripheral edge of the positive terminal plate 35 and negative terminal plate 36 is thermocompression bonded to seal the entire battery.

(Problems to be Solved by the Invention) However, in such a manufacturing method, since the positive and negative terminal plates 35 and 36 and the insulating sealing member 34 are each cut into predetermined shapes, it is difficult to assemble the battery. In addition, positioning them is extremely difficult, and if this positioning is not consistent, the shape of the completed battery will be irregular, resulting in a defective overall shape. Furthermore, since high precision is required for positioning these parts during battery assembly, there are problems such as lower work efficiency and higher unit price of the battery.

In order to solve such problems, we have developed a method in which the power generating unit is surrounded by an insulating seal, placed between the positive terminal plate and the negative terminal plate, and then the entire battery is cut into a predetermined shape at the sealing part. has been disclosed (Japanese Unexamined Patent Publication No. 60-207
(See Publication No. 245). If manufactured in this manner, the shape of the battery can always be kept constant, thereby preventing defects in the overall shape, and also improving work efficiency during assembly.

However, in this manufacturing method, since a laser beam or a rotary cutting tool is used as a cutting means for the sealing portion, the following problems occur.

In other words, when a laser beam is used, in order to melt and cut the positive and negative terminal plates and the insulating sealing body, these
00' (1!) and the insulating sealant would thermally decompose or burn, causing problems such as impairing the sealing properties of the battery.Also, when a rotary cutting tool was used, the positive electrode - Metallic particles are formed on the periphery of the cut surface of the negative electrode terminal plate, which causes problems such as impairing the tightness of the battery and causing short circuits between the positive electrode and the negative electrode terminal plate.

The present invention solves these problems, makes it possible to always keep the shape of the battery constant, eliminate defects in the overall shape, improve workability during assembly, and reduce the price of the battery. It is an object of the present invention to provide a method for manufacturing a flat battery that can prevent a decrease in the density of the battery and a short circuit between the positive and negative terminal plates.

[Structure of the Invention] (Means for Solving the Problems) As a result of intensive studies to achieve the above object, the inventors of the present invention have sealed the entire battery and then injected ultra-high pressure liquid into the sealed part. The present invention was completed based on the idea that the material could be sprayed and cut into a predetermined shape.

That is, in the method for manufacturing a flat battery of the present invention, a power generation unit in which a positive electrode mixture sheet, a separator, and a negative electrode sheet are laminated in this order; a frame-shaped insulating sealing body surrounding the power generation unit; a positive electrode terminal plate that covers and comes into close contact with the surface of the agent sheet and one end face of the insulating cover; a negative electrode terminal that covers and comes into close contact with the surface of the negative electrode sheet and the other end face of the insulating sealing member; In the method for manufacturing a flat battery consisting of a plate, after the entire battery is sealed, the entire battery is sealed in a predetermined position by jetting ultra-high pressure liquid at the sealing portions between the positive terminal plate, the negative terminal plate, and the insulating sealing body. It is characterized by comprising the step of cutting into the shape of.

As described above, the method for manufacturing a flat battery of the present invention is characterized by sealing the entire battery and then cutting the sealed portion into a predetermined shape, which will be explained below based on the drawings.

In FIG. 1, first, a positive terminal plate 11 is prepared. This positive electrode terminal plate 11 has, for example, a rectangular shape, and its vertical and horizontal dimensions are slightly larger than the specified battery dimensions. The positive terminal plate 11 also serves as a battery container, and is made of 5US300, 400.
500 series stainless steel plates, clad plates of these stainless steel plates and nickel plates, external gold-plated nickel stainless steel clad plates, nickel-plated steel plates, and nickel plates are used.

Next, the insulating sealing body 12 is placed on the positive electrode terminal plate 11 described above. The insulating sealing body 12 has a notch 121 formed in its center for accommodating a power generation unit 14, which will be described later, and its vertical and horizontal dimensions are similar to the positive terminal plate 11.
It's almost the same. Moreover, as the insulating sealing body 12,
For example, nylon, polyethylene, polypropylene, methacrylic acid-ethylene copolymer ionomer resin neutralized with metal ions are injection molded using a mold,
Alternatively, these resin sheets may be pressed, pressure-molded, and punched out.

In addition, adhesive layers 131 and 132 are provided on both sides of the insulating sealing body 12.
may be provided. As this adhesive layer, fatty acid polyamide resin based on dimer acid, ionomer resin of methacrylic acid-ethylene copolymer neutralized with metal ions, etc. are used.
It is applied to the surface that comes into contact with the negative terminal plate, or a frame-shaped cutout is attached. Note that depending on the material of the insulating sealing body 12, fusion bonding using ultrasonic waves may be employed without using the adhesive layers 131 and 132. Further, when an ionomer resin is used for the insulating sealing body 12, the adhesive layers 131 and 132 can be omitted because the ionomer resin itself exhibits adhesive properties when heated and pressurized.

Next, the power generation unit 1 is placed in the notch 121 of the insulating sealing body 12.
Accommodates 4. Here, the power generation unit 14 includes a separator 142 made of a nonwoven fabric impregnated with an organic solvent electrolyte on a positive electrode mixture sheet 141 made of a cathode active material, a conductive agent, and a binder.

Furthermore, a negative electrode sheet 143 made of metallic lithium is laminated thereon.

Next, the negative electrode terminal plate 15 is placed so as to cover the surface of the negative electrode sheet 143 and the end face of the insulating sealing body 12 so as to be in close contact therewith, and the peripheral edges of the positive electrode terminal plate 11 and the negative electrode terminal plate 15 are treated with a treatment (not shown). After setting with a tool, heat and pressure are applied to bond and seal the peripheral edges of the positive terminal plate 11 and negative terminal plate 15 and the peripheral edge of the insulating sealing body 12. The battery assembly process up to this point is preferably carried out in dry air or an inert gas such as argon gas in order to prevent moisture from entering the battery.

Next, the sealed battery as described above is cut along broken line A by spraying ultra-high pressure liquid to complete a flat battery having a predetermined shape as shown in FIG. That is, in FIG. 4, an ultra-high pressure hose 162 and an ultra-high pressure liquid injection nozzle 163 are connected to an industrial robot 161.
1 is driven at a constant speed to cut the battery 10 fixed on the battery fixing table 165 along the broken line A. The discharge pressure of the ultra-high pressure liquid at this time is 1000 to 5000 kgf/c.
It is preferable to set it as m2. If it is less than 100,100 O/cm 2 , the cutting condition is not good, and metal flakes may occur at the periphery of the cut surface of the terminal board. On the other hand, 5000
This is because if it exceeds kgf/0m2, a large amount of ultra-high pressure liquid will be used. In addition, the discharge flow rate is 1.0~
101/ωin1, cutting speed is 0.1~Iom/min
, is preferable. Furthermore, although water is mainly used as the liquid used to cut the sealing portion, it may also be water in which an abrasive is dispersed or an organic solvent.

Note that the method for manufacturing a flat battery of the present invention is not limited to only the above-described method, and can be carried out with appropriate modifications within the scope of the gist. That is, the fifth
In the figure, a positive terminal plate 21 is prepared, and a plurality of (
Insulating sealing body 2 having three notches 221 in FIG.
Place 2. Next, after housing the power generation unit 23 in each notch 221, the negative terminal plate 24 is placed thereon,
Positive terminal plate 21, negative terminal plate 24, and insulating sealing body 22
seal the gap between Thereafter, the sealing portion is cut along the broken line B shown in FIG. 6 using ultra-high pressure liquid to complete a plurality of batteries at the same time.

In addition, an insulating sealing body 22 having a plurality of notches is fused to the positive terminal plate 21 and the negative terminal plate 24, respectively, and the power generation unit 23 is accommodated in each notch 221.

Thereafter, the insulating sealing body fused to the positive terminal plate 21 and the negative terminal plate 24 may be opposed to each other, and then the battery may be sealed.

2, although a rectangular flat battery is described, the present invention can also be applied to the assembly of other flat batteries.

Furthermore, the present invention is applicable not only to organic solvent batteries but also to alkaline batteries and manganese batteries.

(Example) Example 1 An embodiment of the present invention will be described based on the drawings.

In Figure 1, first, the thickness is 0.03 mm and the length is 60 mm.
, positive terminal plate 1 made of 5US304 with a width of 80 mIIl.
A positive electrode mixture sheet 141 made of calcined manganese dioxide, graphite powder, and Teflon dispersion and having a thickness of 0.2 mm, a length of 12 mm, and a width of 32 mm was placed on top of the positive electrode mixture sheet 141. next,
Thickness 0.2mm, length 60mm, width 80mm + 12 notches
1 is a frame-shaped insulating sealing body 12 with a length of 14 mm and a width of 34 m + n.
Prepare two sheets, and cut out the notch 12 on the peripheral edge of one sealing body 12.
Thickness 0.1 to cover 1! A separator 142 made of DID polypropylene nonwoven fabric was integrated.

Next, the insulating sealing body 12 obtained by changing the separator 142 to -It is placed on the positive electrode mixture sheet 141 placed on the positive electrode terminal plate 11 to surround the positive electrode mixture sheet 141, and then the positive electrode mixture sheet 141 is placed on the positive electrode terminal plate 11. 11 and the insulating sealing body 12 at 200°C.
It was heat-pressed for seconds.

On the other hand, on the negative electrode terminal plate 12 having the same shape and material as the positive electrode terminal plate 11, a thickness of 0.1+nff1. Height 12mm,
Place the metal lithium sheet 143 horizontally 321, and then
The other insulating sealing body 12 described above is connected to the negative terminal plate 15.
After surrounding the metal lithium sheet 143 by placing it on the second plate,
The negative electrode terminal plate 15 and the insulating sealing body 12 were thermocompression bonded at 200° C. for 2 seconds.

Next, the positive electrode mixture sheet 14 placed on the positive electrode terminal plate ll
The separator 142 on top of 1 is impregnated with an organic solvent electrolyte in which lithium perchlorate is dissolved in propylene carbonate at a concentration of 1 molZ, and then a metal lithium sheet 143 and an insulating sealing body are added thereto. The power generation unit 14 was constructed in the notch 121 of the overlapping insulating sealing body 12 with the negative electrode terminal plate 15 on which the power generation unit 12 is placed facing each other.

Furthermore, the peripheral edges of the positive terminal plate 1 and the negative terminal plate 15 were set in a jig (not shown), and the peripheral edges were heated to 180'C! So 2
The entire battery was sealed by thermocompression bonding for seconds to produce 50 batteries as shown in FIG. The thickness of this battery is 0.46+nm
Met. Note that the battery assembly up to this point was performed in an argon gas atmosphere to prevent moisture from entering the battery.

Finally, the ultra-high pressure hose 162 and the ultra-high pressure liquid injection nozzle 163 are connected to the industrial robot l-161 shown in FIG. 10 along the broken line A with the ultra-high pressure liquid 164 discharged from the ultra-high pressure liquid injection nozzle 163 (discharge pressure 3000 kgf/am2, discharge flow rate 10, l/min, cutting speed 1 m/min), Fifty flat batteries with a length of 20cm and a width of 401!1m were manufactured.

Among these 50 flat batteries, the number of batteries with sealing defects was 0, and the number of batteries with short circuits was 0. This will be explained based on FIGS. 5 and 6.

First, in FIG. 5, three notches 221 (vertical 34 m
m, width 141), thickness 0.2+in, length 80mm
, an insulating sealing body 2 made of ionomer resin with a width of 1201
2 was placed on a positive terminal plate 21 made of a stainless steel plate with a thickness of 0.03 mm, a length of 80 mm, and a width of 120 mm.

Next, a power generation unit 23 similar to that of Example 1 was housed in each notch 221, and then a negative terminal plate 24 made of the same material and shape as the positive terminal plate 21 was placed. Thereafter, these were sealed by thermocompression bonding under the same conditions as in Example 1. Furthermore, when 60 batteries were manufactured by cutting the sealing portion along the broken line B shown in FIG. 6 in the same manner as in Example 1, no defects in appearance, defects in sealing, or short circuits occurred in the batteries.

Comparative Example 1 After manufacturing 50 flat batteries in the same manner as in Example 1,
Carbon dioxide laser (output 500W, cutting speed 10m/mi
The battery 10 was cut along the rupture iA using a cutter.

Of these 50 flat batteries, the number of batteries with poor sealing was 7, and the number of batteries with short circuits was 0. Comparative Example 2 50 flat batteries were produced in the same manner as in Example 1. After manufacturing,
Using a rotary cutting device, cut the battery 10 along the broken line A (rotation speed 1500 rpm, cutting speed 1, 5 m/
min,) Shita.

Among these 50 flat batteries, the number of batteries with sealing defects was one, and the number of batteries with short circuits was eight.

[Effects of the Invention] As is clear from the above explanation, the flat battery manufactured by the manufacturing method of the present invention is cut into a predetermined shape after sealing the entire battery, so that the battery shape can always be kept constant. As a result, defects in the overall shape can be completely eliminated. Furthermore, it is possible to improve work efficiency during battery assembly and to reduce the cost of batteries. Furthermore, since an ultra-high pressure liquid is used for cutting, thermal decomposition of the sealant does not occur, thereby preventing deterioration of the sealing performance of the battery and short circuit between the positive and negative terminal plates. Therefore, its industrial value is great.

[Brief explanation of the drawing]

1 and 2 are schematic configuration diagrams of a flat battery for explaining the manufacturing method of the present invention, and FIG. 3 is a longitudinal cross-section of a flat battery obtained by an example of the manufacturing method of the present invention. side view,
FIG. 4 is a schematic diagram showing the cutting means used in the manufacturing method of the present invention, FIG. 85 and FIG. 6 are schematic diagrams of a flat battery for explaining the manufacturing method of the present invention, and FIG. , is a longitudinal cross-sectional view of a flat battery manufactured by a conventional manufacturing method. 11.21.35...Positive terminal plate 12.22.34...Insulating sealing body 121.221...Notch 131.132...Adhesive layer 14.23...Power generation unit 141.31 ...Positive electrode mixture sheet 142.33...Separator 143.32...Negative electrode sheet 15.24.36...Negative electrode terminal plate 10...Battery 181...Industrial robot 162...Super High pressure hose 163...Ultra high pressure liquid injection nozzle 164...Ultra high pressure liquid 165...Battery fixing table Fig. 3 Fig. 6 Fig. 7

Claims (2)

[Claims] (1) A power generation unit in which a positive electrode mixture sheet, a separator, and a negative electrode sheet are laminated in this order; a frame-shaped insulating sealing body surrounding the power generation unit; a surface of the positive electrode mixture sheet and the insulating sealing body; A flat battery is manufactured, comprising: a positive electrode terminal plate that covers one end face and is in close contact with these; and a negative electrode terminal plate that covers and is in close contact with the surface of the negative electrode sheet and the other end face of the insulating sealing body. The method includes the step of, after sealing the entire battery, cutting the entire battery into a predetermined shape by jetting ultra-high pressure liquid at the sealing portions between the positive terminal plate, the negative terminal plate, and the insulating sealing body. A method for manufacturing a flat battery characterized by: (2) The discharge pressure of the ultra-high pressure liquid is 1000 to 5000k.
The method for manufacturing a flat battery according to claim 1, wherein the flat battery has a gf/cm^2.