JP3325227B2 - Assembly manufacturing method of lithium ion polymer type secondary battery - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for assembling and manufacturing a lithium ion polymer type secondary battery.
In particular, while attaching a continuous film to a carrier material and transporting them continuously, a lithium ion polymer type secondary battery is assembled to improve productivity and assembly accuracy, and can be used for mass production. The present invention relates to a method for assembling and manufacturing a battery.

[0002]

2. Description of the Related Art The basic structure of a lithium secondary battery is a positive electrode, a negative electrode, and a separator holding an electrolyte interposed between both electrodes. Of these, the positive electrode and the negative electrode are coated with a slurry made by mixing and dispersing a plasticizer in a dispersion medium, if necessary, for the active material, the conductive material, and the binder. And a collector attached to a current collector such as a metal mesh. As the positive electrode active material, a transition metal lithium oxide is most suitable. For example, lithium manganate (LiMn ₂ O ₄ ), lithium cobaltate (LiCoO ₂ ), lithium nickelate (LiNiO ₂ )
₂ ) and the like are preferred. Further, the negative electrode active material is a known material capable of storing and releasing lithium ions, and for example, a carbon material having lithium ion storing ability is preferable. Among carbon materials, coke-based carbon and graphite-based carbon are more preferable. The conductive material is a known material having electronic conductivity, for example, natural graphite, carbon black, acetylene black, and the like, and a mixture thereof can also be used. As the binder, a fluororesin is preferable, and polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVD)
F), hexafluoropropylene (HFP) and the like are preferable, and copolymers thereof can also be used. As a dispersion medium,
Organic solvents capable of dissolving the binder are suitable, for example, acetone, methyl ethyl ketone (MEK), tetrahydrofuran (THF), dimethylformamide, dimethylacetamide, tetramethylurea, trimethyl phosphate, N-methylpyrrolizone (NMP) Are preferred. As the plasticizer to be added as needed, an organic solvent that can be replaced with an electrolytic solution after film formation is appropriate, and phthalic acid diesters are preferable. Current collectors include stainless steel, nickel, aluminum, titanium,
Copper punched metal and expanded metal are preferable, and a material subjected to surface treatment can also be used. The electrolyte is generally composed of a solvent and a lithium salt dissolved in the solvent. Examples of the solvent include organic solvents such as polyethylene carbonate, ethylene carbonate, dimethyl sulfoxide, butyl lactone, sulfolane, 1,2-dimethoxyethane, tetrahydrofuran, diethyl carbonate, methyl ethyl carbonate, and dimethyl carbonate, and one or more of these. Are preferably used in combination. As the lithium salt, LiCF ₃ SO ₃ , L
iAsF ₆ , LiClO ₄ , LiBF ₄ , LiPF _{6 and the} like are preferable.

FIG. 11 is an assembly view of a battery B of a lithium ion polymer type secondary battery. The negative electrode A is sandwiched between the two front and rear positive electrodes C, C via the separators S, S. Current collector tabs protrude from the positive and negative electrodes. In order to prevent current leakage at the edge, the negative electrode A and the separator S project from the positive electrode C in all directions.

Conventionally, a method of assembling and manufacturing a lithium ion polymer type secondary battery has been performed in a form as shown in FIG. First, an electrode film and a separator are made larger, and are punched into a predetermined shape by a mold. Next, the punched positive electrode film, negative electrode film and separator were
The batteries were assembled one by one with tweezers or the like, and then bonded together by lamination. In this way, one battery
Since the parts are assembled one by one, there is a disadvantage that the assembling accuracy and productivity are very poor.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks and to assemble a lithium ion polymer type secondary battery while attaching a continuous film to a carrier material and transporting them continuously. Another object of the present invention is to provide a manufacturing method capable of improving productivity and assembling accuracy and corresponding to mass production.

[0006]

The above object of the present invention is attained as follows. (A) An electrode film of a lithium ion polymer type secondary battery is attached to a carrier material, and is further positioned with a mold.
A semi-perforated hole is formed, the electrode film is continuously conveyed using the strength of the carrier material and the reference hole , and the outer shape of the electrode film is processed on the carrier material to continuously perform battery assembly. (B) A positioning reference hole is opened with a mold on a lithium ion polymer type secondary battery electrode film attached to a carrier material, and the outer shape processing of the electrode film and the positioning of the battery assembly are performed using the reference hole. . (C) The externally processed positive electrode film is intermittently transferred from a carrier material to both surfaces of the externally processed negative electrode film at regular intervals, and a lithium ion polymer type secondary battery is continuously assembled, and finally, a metal mold is used. Disconnect into individual batteries.

[0007] Thus, the present invention provides (1) a carrier material, stuck lithium ion polymer type secondary battery electrode film, further, the positioning based on the mold
A method for manufacturing a battery assembly, comprising: forming a quasi-hole, continuously transporting the electrode film using the strength of the carrier material and the criterion hole , externally processing the electrode film on the carrier material, and continuously performing battery assembly. (2) A positioning reference hole is opened with a mold on a lithium ion polymer type secondary battery electrode film attached to a carrier material, and the outer shape processing of the electrode film and the positioning of the battery assembly are performed using the reference hole. (3) The externally processed positive electrode film is intermittently transferred at regular intervals from a carrier material to both surfaces of the externally processed negative electrode film, and the lithium ion polymer secondary battery is manufactured. Are continuously assembled, and finally separated into individual cells by a mold.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, a positive electrode material, a negative electrode material and a separator material are applied on a carrier material 1 respectively to form a positive electrode material film 2, a negative electrode material film 3 and a separator film 4 individually. Is shown. After these films are formed, they are wound into a roll.

The positive electrode slurry and the negative electrode slurry are each formed into a film so that the adhesiveness in the film forming step and the easy peelability in the subsequent step are good and the same carrier film can be used throughout the manufacturing process. To produce a cathode film and an anode film, the carrier film has a center line average roughness of 0.01 μm to 1.0 μm.
μm (based on the evaluation method according to JIS B0601), 60 °
Glossiness (G _S 60 °) is .5 to 140% (JIS Z
It is preferable to use a polyester film which has been subjected to a roughening process (according to the evaluation method of 8741).

FIG. 2 shows a slitting step of cutting each of a positive electrode material film, a negative electrode material film, and a separator film coated on a carrier material into a predetermined width. Here, the slitting is performed in two stations, but the slitting can be performed in three or more stations. The positive electrode material film, the negative electrode material film and the separator film cut to a predetermined width are each 2 ′,
Shown as 3 'and 4'.

3 and 4, each of the positive electrode material film 2 'and the negative electrode material film 3' cut to a predetermined width is sandwiched by a current collector 5 shown here as a current collector mesh. The lamination process of the positive electrode and the negative electrode in which the positive electrode film 6 and the negative electrode film 7 are separately formed by bonding and laminating on both surfaces of the negative electrode film 6 is shown. Here, a current collector made of copper is shown as a current collector, but a stainless steel, nickel, aluminum, titanium, a punched metal of copper, an expanded metal is preferable for the current collector, and a material subjected to a surface treatment can also be used. . At this time, the bonding positions of the front and back films are accurately adjusted by using an electrical method such as image processing.

In this case, after lamination, only the carrier material 1 on the surface of the positive electrode film is peeled off.
Positive electrode film 6 from which only carrier material 1 on the surface is peeled off
Is wound into a roll. For the negative electrode film, the front and back carrier materials 1 and 1 are peeled off.

As shown in the downstream part of FIG. 4, on the negative electrode film from which the carrier materials 1 and 1 have been peeled off, a separator drawn out from a roll-shaped separator film 4 ′ is attached to both surfaces thereof, and a roll-shaped separator is provided. The negative electrode film 8 is formed. In the same manner as the above-described method, the positions of both sides are also adjusted. In FIG. 4, a current collector lamination process of the negative electrode, a process of peeling the carrier materials 1 and 1 on the front and back of the negative electrode film, a process of attaching a separator, and a process of forming a roll-shaped negative electrode film 8 with a separator are continuously shown. .

Thus, the positive electrode film 6 and the negative electrode film with separator 8 are formed. After the outer shape processing as described below,
Assembled to complete the battery shown in FIG.

(Positive electrode film outer shape processing) In FIG. 5, the positive electrode film 6 is unwound. The unwound positive electrode film 6 is externally processed by the mold 12 in the order of punching out positioning reference holes, punching out a current collector mesh, and half-cutting the outer shape. After the outer shape processing, the unnecessary fractured material 9 at the center of the positive electrode film is removed. The positioning of the film
The positioning is performed by inserting the positioning transport sprocket 11 into the positioning reference hole (sprocket hole) 10. An encoder is attached to the positioning / conveying sprocket 11, and controls the feed amount of the positive electrode film. The punched current collector mesh tab is shown as number 13. FIG.
The appearance of half-cut is shown in FIG.

(Negative electrode film outer shape treatment) In FIG. 7, a negative electrode film 8 with a separator is also shown in FIG.
Similarly to the above, the outer shape is processed by the mold 12 'in the order of the positioning reference hole punching and the current collecting mesh punching. The positioning of the film is performed by inserting the positioning transport sprocket 15 into the positioning reference hole 14. An encoder is attached to the positioning transport sprocket 15,
The feed amount of the negative electrode film is controlled. The punched current collector mesh tab is shown as number 16.

(Battery Assembling Process) Next, as shown in FIGS. 8 and 9, a battery is assembled from the negative electrode film 8 and the positive electrode film 6 subjected to the outer shape treatment. The outer shape-treated negative electrode film 8 is unwound, and the attached carrier material 1 is peeled off. The positive electrode film 6 whose outer shape has been processed is unwound on both surfaces thereof, and the positive electrode film 6 is intermittently transferred by the transfer roll 17 at the same position on both surfaces while separating from the carrier material. The carrier material is removed.

The intermittent transfer is, as shown in detail in FIG.
The externally processed positive electrode film 6 is heated (50 to 13
(0 ° C.), the transfer rolls 17 and 17 are closed, and the transfer is performed from the carrier material 1 to the negative electrode film 8 subjected to the outer shape treatment. When the positive electrode film 6 for one battery is transferred, the transfer rolls 17 and 17 are opened up and down, and at the same time, the transport of the positive electrode film 6 is stopped. At this time, the negative electrode film 8 continues to be transported, and has a predetermined interval (for example, 1.
5 mm), the transfer rolls 17 and 17 are closed, the conveyance of the positive electrode film 6 is restarted, and the next transfer is performed. The above operation is repeated to perform intermittent transfer continuously.
As shown in FIG. 8, the positioning of each film at the time of this transfer is also performed by positioning the positioning reference hole and the positioning transport sprocket 1.
8 is performed.

After the transfer, as shown in FIG. 9, lamination is performed using a metal heat roll 19, and finally, the individual batteries are separated by a battery punching die 20. The cut piece 21 of the negative electrode film at the central portion after being cut off is wound up and removed.

After that, the battery cells are activated in a dehumidifying atmosphere, put in a package film, packaged and shipped.

As described above, according to the present invention, in order to continuously transport the electrode film, the electrode film needs to have a tensile strength. Materials (eg PET)
Is attached by lamination or the like to give strength to the carrier material. By this means, high-speed continuous transport of the electrode film and insertion of the transport sprocket into the positioning reference hole are made possible. As shown in FIG. 11, in order to continuously assemble the battery with a structure in which the negative electrode and the separator protrude in all directions from the positive electrode, the means of intermittently transferring the positive electrode film from the carrier material to the negative electrode film (with separator) solves the problem of continuous assembly. Settled. In order to perform the transfer, the outer shape of the electrode film must be processed before the transfer, and the processing is performed using a mold. In the mold processing and assembly, the positioning reference is important, but in the present invention, it was solved by first forming a positioning reference hole with a die in the center of the electrode film. By using the positioning reference hole and the positioning transport sprocket, inexpensive and highly accurate positioning can be performed. The outer shape treatment of the positive electrode film 1 on the carrier material was solved by half cutting.

Thus, the present invention provides, as an overall process, a first step: applying a positive electrode material, a negative electrode material, and a separator to a carrier material, and winding and winding the same; a roll-shaped positive electrode material film, a negative electrode material film, and a separator film A second step: cutting each of the positive electrode material film, the negative electrode material film and the separator film into a predetermined width, and separately forming the roll-shaped positive electrode material film, the negative electrode material film and the separator film. A slitting step to be formed; a third step: bonding the cut positive electrode material film and the cut negative electrode material film to both surfaces of the current collector with a current collector therebetween, laminating the cut, and forming a positive electrode film and The negative electrode film is formed separately. In this case, after lamination, the positive electrode film A) A positive electrode and a negative electrode current collector lamination step of peeling off only the film and winding up the roll-shaped positive electrode film, while removing the front and back carrier films for the negative electrode film; A separator-attached anode electrode film forming step in which a separator film is further attached to both surfaces of the anode electrode film from which the film has been peeled off; 5th step: the current-collecting mesh portions on both side edges of the cathode electrode film and the separator-attached anode electrode film are formed of gold. A punching step of punching into a predetermined shape with a mold, a sixth step: a positive electrode film cutting step of cutting only the positive electrode film on the carrier film into a predetermined shape with a mold, a seventh step: from a negative electrode film with a separator. Removed carrier film on both sides A transferring step of transferring the positive electrode film half-cut on both surfaces of the negative electrode film with the separator to a predetermined position at a predetermined interval, and an eighth step: laminating the transferred positive electrode film and the negative electrode film with the separator. Laminating step, Ninth step: a punching step of punching an assembly obtained by laminating the transferred positive electrode film and the negative electrode film with a separator into individual batteries using a mold, wherein the secondary step is a lithium ion polymer type secondary step. A method for manufacturing a battery is provided.

[0023]

As described above, high productivity can be obtained by assembling the lithium ion polymer type secondary battery by transporting the long film. In addition, since the assembling is performed on the carrier material, the device can be mechanically or electrically positioned by devising the positioning of the carrier material, and high assembling accuracy can be obtained. Further, by changing the cutting width and the mold in the second step, it is possible to easily cope with various product shapes. Thus, according to the present invention, (1) productivity is enhanced, (2) automation is achieved, (3) assembling accuracy is increased, and (4) the product shape can be easily changed in the production of a lithium ion polymer type secondary battery. .

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a film forming step of coating a positive electrode material, a negative electrode material and a separator material on a carrier material, respectively, and separately forming a positive electrode material film, a negative electrode material film and a separator film.

FIG. 2 is an explanatory view showing a slitting step of cutting a positive electrode material film, a negative electrode material film, and a separator film into respective predetermined widths.

FIG. 3 shows a positive electrode current collector lamination step of laminating a positive electrode material film cut into a predetermined width on both sides of the current collector with a current collector interposed therebetween and forming a positive electrode film. FIG.

FIG. 4 is an explanatory view showing a current collector lamination step of a negative electrode, a step of peeling a carrier material on the front and back of a negative electrode film, and a step of attaching a separator to form a roll-shaped negative electrode film with a separator.

FIG. 5 is an explanatory diagram for performing outer shape processing of a positive electrode film.

FIG. 6 is a perspective view showing a half cut aspect of a positive electrode film.

FIG. 7 is an explanatory view showing an outer shape treatment of a negative electrode film with a separator.

FIG. 8 is an illustration showing a process of transferring a half-cut positive electrode film on both sides of a negative electrode film with a separator to a predetermined position, laminating, and finally punching the assembly into individual batteries by using a mold. FIG.

FIG. 9 is a perspective view showing an assembled state of the battery of FIG. 8;

FIG. 10 is an explanatory diagram for explaining an intermittent transfer flow in a stepwise manner.

FIG. 11 is a perspective view of a battery assembly.

FIG. 12 is a flowchart showing a conventional battery assembly aspect.

[Explanation of symbols]

C positive electrode A negative electrode S separator 1 carrier material 2 positive electrode material film 3 negative electrode material film 4 separator film 2 ′, 3 ′, 4 ′ cut positive electrode material, negative electrode material and separator film 5 current collector 6 positive electrode film 7 negative electrode film 8 Negative electrode film with separator 9 Central broken material 10 Positive electrode positioning reference hole 11 Conveyor sprocket 12 Mold 13 Current collecting mesh tab 14 Negative electrode positioning reference hole 15 Positioning / conveying sprocket 16 Current collecting mesh tab 17 Transfer roll 18 Positioning / conveying sprocket 19 Metal heat Roll 20 Battery punch 21 Negative electrode film broken material

Claims (3)

(57) [Claims] 1. A lithium ion polymer type secondary battery electrode film is stuck on a carrier material, and a positioning reference hole is opened with a mold, and the strength and reference hole of the carrier material are used. A method of manufacturing a battery assembly, comprising continuously transporting an electrode film, externally processing the electrode film on a carrier material, and continuously performing battery assembly. 2. A positioning reference hole is opened with a mold on a carrier material on which a lithium ion polymer type secondary battery electrode film is adhered, and the outer shape processing of the electrode film and the positioning of the battery assembly are performed using the reference hole. And a method for producing and assembling a battery. 3. The externally processed positive electrode film is intermittently transferred from the carrier material at regular intervals to both surfaces of the externally processed negative electrode film, and a lithium ion polymer secondary battery is continuously assembled. A method for producing and assembling a battery, wherein the battery is separated into individual batteries by a mold.