JPH05314994A - Manufacture of battery - Google Patents

Abstract

PURPOSE:To enhance productivity, lower a temperature rise and provide a cylindrical battery free from shortcircuit and a wrinkle on an electrode plate by laminating and integrating current collecting metal and an active material on both sides of a resin film, and then removing a part of the metal and active material for forming a patternized electrode plate. CONSTITUTION:Current collecting metal is formed respectively on both sides of a resin film, a negative electrode active material 4' is stacked thereon, and then molded for integration with each other. A part of the molded product is removed by irradiating a laser beam, thereby providing a negative electrode plate as a patternized electrode plate having a large current cutout section 7' and an electrochemical reaction section 8. Similar positive and negative electrode plates are superposed on top of each other, and wound like a cylindrical form. In this case, no mask is needed and productivity becomes high. Thus, a spiral battery becomes available with such characteristics as thin active material layer, a small temperature rise, and freedom from shortcircuit even in some lateral dislocation of the electrode plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a thin battery used in the fields of electronic equipment, toys, accessories, electric vehicles and the like.

[0002]

2. Description of the Related Art In a conventional battery, an adhesive is placed around the periphery of a positive electrode current collector, a positive electrode active material is placed in the central area of the inner surface of the positive electrode current collector (a region where no adhesive is present), and the positive electrode active material is further disposed. An electrolyte is arranged on the material surface to produce a positive electrode plate. Further, a negative electrode adhesive frame whose inner size is slightly smaller than the positive electrode adhesive frame is arranged on the periphery of the negative electrode current collector, and a negative electrode active material such as lithium or carbon is provided in the central area of the inner surface of the negative electrode current collector. And further or an electrolyte on the surface of the negative electrode active material to prepare a negative electrode plate. The positive electrode plate and the negative electrode plate thus produced are stacked on each other with their inner surfaces overlapped with each other, and the positive electrode / negative electrode adhesive is heat-sealed from above the current collector under reduced pressure or under pressure to seal the battery. I was making it. Further, when the battery capacity of the battery is increased, the amount of active material is increased to increase the thickness.

In such a structure, after the adhesive is arranged and processed (only the outer frame is formed by half cut, etc.), the positive electrode active material is arranged inside the adhesive (by coating and printing) and the electrolyte. It was difficult to register when arranging, and in the case of continuous processing, a shift in the length direction sometimes occurred. Further, there was a similar problem on the negative electrode side. Furthermore, by stacking and bending such electrode plates,
When wound in a spiral shape, the electrochemical reaction part (working surface) of the electrode plate may be slightly displaced between the positive electrode and the negative electrode, and the adhesive may be peeled off or an electrical short circuit may occur inside. Note that this tendency was remarkable when the battery capacity was increased.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to improve productivity and reduce the temperature rise of a battery due to heat generation at high rate discharge. , If the active material surface of each electrode plate is faced on top of each other and further folded or spirally wound, even if the working surface (active material surface) of each electrode plate is slightly displaced, it will not short-circuit and An object of the present invention is to provide a method for manufacturing a battery in which wrinkles do not occur on each electrode plate on the outside.

[0005]

Means for Solving the Problems The present invention achieves the above object, and provides a method for manufacturing a battery in which a positive electrode active material, an electrolyte, and a negative electrode active material are arranged between a positive electrode current collector and a negative electrode current collector. , A current collector metal is formed on both sides of a resin, and a part of the current collector metal and the active material is removed from a molded article in which the active material is integrally formed on the resin, and a constant pattern is formed on the resin. Forming an electrode plate having a resin, the removal is performed by laser or ceramics fine powder jet cutting, the pattern forms a current collecting portion, a large current cutting portion and an electrochemical reaction portion,
The current collectors of each electrode plate are connected to each other, the active material is not formed in the current collector, and either or both of the positive electrode plate and the negative electrode plate having the certain pattern. An electrolyte is disposed on the surface of the surface other than the current collecting part, the resin is a series of films, and the negative electrode current collector metal is copper and is coated with lithium or carbon as the negative electrode active material. That is, the current collecting portion of the positive electrode plate and the current collecting portion of the negative electrode plate are opposed to each other, and the battery element having the active material surface facing each other is spirally wound, and the upper end portion and the lower end portion are terminals of each electrode. The above problems are solved by this.

[0006]

According to the first aspect, the collector metal and the active material can be formed on the resin by the continuous pattern, and the productivity is improved. Further, each electrode plate can be made thin and the battery capacity can be increased. Claim 2
The constant pattern formation by the laser can be processed while winding the resin, and the productivity is good. In addition, ceramic fine powder jet cutting does not raise the temperature of the laser method (the laser method may increase the resin temperature and cause deformation if the removal thickness is thick), and it is possible to integrally remove thick layers. However, there remains a concern that a small amount of ceramic fine powder will adhere. However, these means can be selectively used depending on the thickness to be processed and the material. For example, ceramics fine powder jet cutting is suitable for forming a negative electrode plate. According to claim 3, by forming a current collector, a large current breaker, and an electrochemical reaction part on the electrode plate, the current collection is facilitated, and even if an abnormal current flows, it is fused at the constriction of the large current breaker. It is possible to prevent heat generation of the battery and separate the defective electrode plate. Moreover, a large-capacity electrode plate can be manufactured by connecting the current collectors of the same electrode plates, and each electrode plate operates normally when the above-mentioned abnormality occurs. And increase productivity. According to the fourth aspect, it is possible to integrally join the current collectors at the ends, for example, when the electrode plate is spirally wound. According to the fifth aspect, no special masking is required at the time of coating the electrolyte, a positional deviation error due to registration does not occur, and the production equipment can be simplified. According to the sixth aspect, the number of electrode plates of the battery can be increased, the battery capacity can be increased, and continuous production can be performed, and the battery can be cut at an arbitrary position as necessary, and batteries of various capacities (number of electrode plates) can be manufactured. According to claim 7, the negative electrode active material has corrosion resistance, the battery life is improved, and the processing according to claim 2 is facilitated. It also enhances the adhesion to lithium and carbon.
According to the eighth aspect, the positive electrode active material has corrosion resistance, the battery life is improved, and the processing according to the second aspect is facilitated.
According to the ninth aspect, the battery capacity can be increased, and the terminal portions of the respective poles can be formed in the vertical direction to improve the electric insulation and facilitate the mounting on the device.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. Figure 1 shows a strip-shaped resin film (for example, PET with both sides coated with PP with a thickness of about 15 μm) 1 on the entire surface except the lower end portion (width of about 3 mm) with a thickness of about 300 Å or more of aluminum as a collecting metal. 2 shows a current collector 3 integrated with a resin film obtained by vacuum vapor deposition of 2 (methods such as gas deposition, VAD, PVD etc. for thick coating, sputtering etc. for thin coating). FIG. 2 shows a molded product 5 in which the positive electrode active material 4 is coated on the entire surface of the resin film integrated current collector 3 excluding the upper end portion and the lower end portion on the aluminum 2 surface by vapor deposition to a thickness of about 500 Å. FIG. 3 shows that the positive electrode active material 4 and the aluminum 2 are simultaneously exposed by adjusting the movement of the resin film 1 and the irradiation position control of the laser light from above the positive electrode active material 4 of the molded product 5. The positive electrode plate 9 was produced by removing it with a fixed pattern to form a current collecting part 6, a large current cutting part 7 and an electrochemical reaction part 8. At this time, the positive electrode plate is also formed on the back surface of the resin film as shown by the dotted line in FIG. 2, the current collecting portions of the respective positive electrode plates are connected to each other, and the current collecting portion 6 and the large current cutting portion 7 are connected. The positive electrode active material 4 is not coated and formed on the.
As a method in which the positive electrode active material 4 is not formed on the current collecting portion 6 and the large current cutting portion 7, the electrochemical reaction portion 8 is previously prepared.
The positive electrode active material 4 may be coated in a width corresponding to, or the laser irradiation light to the current collecting part 6 and the large current cutting part 7 may be reduced. Although the gap 10 between the electrochemical reaction portion 8 and the electrochemical reaction portion 8 of the adjacent positive electrode plate shown in FIG. 3 is vertical, it is better to remove it obliquely to improve productivity. The large current cutting portion 7 is constricted so that the large current cutting portion is quickly melted when a large current flows. As shown in FIG. 4, the removal by the laser is performed by irradiating the laser light once in the lateral direction with a width of about 1 mm and once in the vertical direction, and having the pattern. A positive electrode plate was formed.

Next, as shown in FIG. 5, the entire positive electrode plate including the gap 10 (including the current collector 6
(Excluding the above) was coated with the solid electrolyte 12. Note that it is better not to cover the large current cutting portion 7 with the solid electrolyte 12 in order to obtain airtightness by adhering to the counter electrode plate in the lateral gap 11 including the large current cutting portion 7. Further, depending on the use of the battery, a polyolefin-based microporous membrane (trade name: DURAGARD) may be arranged instead of the solid electrolyte 12.

On the other hand, the negative electrode plate was also manufactured by the same method. They are structurally almost the same, and will be described with reference to the respective drawings in the case of the positive electrode.
Attach. A strip-shaped resin film (for example, PET with both sides coated with PP to a thickness of about 15 μm) 1'on the entire surface except for the lower end (width of about 3 mm) with a thickness of about 300 Å or more copper as a collector metal 2 A current collector 3'integrated with the resin film 1'deposited with vacuum was prepared. Then, the negative electrode active material 4 '(lithium or carbon) except the upper end portion and the lower end portion on the copper 2'side of the resin film integrated current collector 3'is vapor-deposited on the entire surface to a thickness of about 200 Å. A coated molding 5'was produced. Next, the negative electrode active material 4 and the copper 2 ′ are adjusted by adjusting the movement of the resin film 1 ′ and the laser light irradiation position control over the negative electrode active material 4 ′ of the molded product 5 ′. Were simultaneously removed with a constant pattern to form a current collecting portion 6 ', a large current cutting portion 7', and an electrochemical reaction portion 8 ', and a negative electrode plate 9'was produced. At this time, as in the case of the positive electrode, a negative electrode plate is also formed on the back surface of the resin film as shown by the dotted line in FIG. 2, the current collecting portions of the negative electrode plates are connected to each other, and the current collecting portion 6 is connected. The negative electrode active material 4'is not coated on the'and the large current cutting portion 7 '. As a method of not forming the negative electrode active material 4 ′ on the current collecting portion 6 ′ and the large current cutting portion 7 ′, the negative electrode active material 4 ′ may be coated in advance to a width corresponding to the electrochemical reaction portion 8 ′, or For example, the laser irradiation light to the current collector 6'and the large current disconnector 7'can be reduced. Although the gap 10 'between the electrochemical reaction portion 8'and the electrochemical reaction portion 8'of the adjacent negative electrode plate shown in FIG. 3 is vertical, it is better to remove it obliquely to improve productivity. good. The large current cutting portion 7'is constricted so that the large current cutting portion quickly melts when a large current flows.

The positive electrode plate and the negative electrode plate manufactured in this way can be formed thinner than about 1/3 of the conventional one. In addition, no special masking is required, the active material can be easily coated, and the production speed of the electrode plate is about 2.4 to 3.1 times that of the conventional method. Further, the above-mentioned embodiment, which is the main point of the present invention, is further advanced,
A case where the positive electrode plate is formed on both surfaces of the resin and the negative electrode plate is formed on both surfaces of another resin will be described.

FIG. 4 shows a series of negative electrode plates in which copper as the negative electrode current collector metal and carbon as the negative electrode active material are integrally removed on both sides of the resin film. The positive electrode has the same structure as the negative electrode plate and will not be particularly described. The current collecting portion of the negative electrode plate and the current collecting portion of the positive electrode plate face each other (that is, the current collecting portion of the negative electrode plate faces upward and the current collector portion of the positive electrode plate faces downward).
Note that the reverse is also possible. ) And superimposing them (while superimposing them), they were spirally wound around the core material as shown in FIG. 5 to form a cylindrical shape. Next, a solder 13 of zinc, lead-tin alloy or the like was welded to the current collectors 6 ′ and 6 located on the upper and lower surfaces of the spiral battery (cylindrical battery). FIG. 6 shows a state in which a part of the vertical cross section of FIG. 5 is enlarged in the thickness direction. When forming the electrode plate, the zinc fine powder 13 may be applied to the current collectors 6'and 6 surfaces in advance. The heat at the time of welding causes the resin films on the upper and lower surfaces to be fused and the entire battery is hermetically sealed.
Will be

The spiral battery (cylindrical battery) thus manufactured has a positive electrode plate 9 and a negative electrode plate 9'even if it is thinly wound in a spiral shape.
The horizontal displacement of the electric reaction parts 8 and 8'is small, and even if the horizontal displacement is caused, the electrolyte 12 intervenes, so that there is no electrical short circuit and the production is easy. Furthermore, since the thickness of the active material layer is thin, the amount of heat generated in each of the electric reaction parts 8 and 8'is small even when discharged with a large current, and the heat is radiated from the upper and lower current collecting terminal parts and the temperature of the battery itself does not rise. Few. When discharged at the same current, if the conventional battery temperature is about 65 ° C, about 3
It becomes 9 ° C. This is advantageous in, for example, motor drive applications (electric vehicles, etc.) that require a large capacity and high rate discharge.

[0013]

As described above, the present invention has the following effects. (1) It can be made thin. (2) Each process can be processed continuously, resulting in high production. (3) No need for masking and high processing accuracy. (4) It is not necessary to use an ultra-thin rolled metal material, and the production cost is low. (5) There is no internal short circuit due to lateral displacement of the electrode plates even if they are superposed and wound in a spiral shape. (6) The battery can be easily sealed. (7) Little increase in battery temperature due to high rate discharge. It should be noted that the present invention is not limited to those shown in the examples, and the resin material / thickness / configuration, current collector metal material /
Thickness / porosity, active material / thickness, electrolyte material / thickness,
The details such as size and shape and the number of patterns are not particularly limited, and may be variously changed according to the application.

[Brief description of drawings]

FIG. 1 is a plan view of a current collecting metal according to the present invention formed on a resin.

FIG. 2 is a plan view of a resin film in which a positive electrode active material is formed on the current collecting metal of FIG.

FIG. 3 is a plan view of a patterned positive electrode plate after removing FIG. 2 by laser irradiation.

FIG. 4 shows a state of formation of a series of negative electrode plates on the back surface of the resin film of FIG.

5 is a perspective view of a series of positive electrode plates formed in the same manner as the series of negative electrode plates of FIG. 5 wound in a spiral shape with an electrolyte interposed and a current collector facing each other.

FIG. 6 shows an enlarged cross-sectional view of the main part of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Resin film 2 Aluminum 4 Positive electrode active material 6,6 'Current collecting part 7,7' Large current cutting part 8,8 'Electrochemical reaction part 10,11 Gap 12 Electrolyte 2'Copper 4'Negative electrode active material 13 Solder

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical indication H01M 10/40 Z

Claims (9)

[Claims] 1. A method for manufacturing a battery in which a positive electrode active material, an electrolyte, and a negative electrode active material are arranged between a positive electrode current collector and a negative electrode current collector, wherein a current collector metal is formed on both surfaces of a resin, and The present invention is characterized in that a current collector metal and a part of the active material are removed from a molded article formed by integrally forming the active material on the resin to form an electrode plate having a certain pattern on both surfaces of the resin. Battery manufacturing method. 2. The method for producing a battery according to claim 1, wherein the removal is performed by laser or ceramic fine powder jet cutting. 3. The pattern according to claim 1, wherein the pattern forms a current collecting part, a large current cutting part, and an electrochemical reaction part, and the current collecting parts of the respective electrode plates are connected to each other. Battery manufacturing method. 4. The method of manufacturing a battery according to claim 3, wherein the active material is not formed on the current collector. 5. The battery according to claim 1, wherein the electrolyte is disposed on a surface of the positive electrode plate or the negative electrode plate having the constant pattern, or both surfaces of the positive electrode plate and the negative electrode plate, excluding the current collecting portion. Manufacturing method. 6. The method for manufacturing a battery according to claim 1, wherein the resin is a series of films. 7. The method for producing a battery according to claim 1, wherein the negative electrode current collector metal is copper, and the negative electrode current collector metal is coated with lithium or carbon as a negative electrode active material. 8. The method for producing a battery according to claim 1, wherein the positive electrode current collector metal is aluminum, and the positive electrode active material is coated thereon. 9. A battery element having a positive electrode collector and a negative electrode collector facing each other and having active material surfaces facing each other is spirally wound, and upper and lower ends are terminals of respective electrodes. The method for manufacturing a battery according to claim 1, wherein: