JPH0729577A - Thinned type battery and manufacture of the same - Google Patents

Abstract

PURPOSE:To facilitate the assembling and serial/parallel connecting of battery elements that could provide a high productivity and would produce no defects, by making a conductive agent that serves as a current collector, printable and printing it on a base material member. CONSTITUTION:A conductive agent (such as, for example, soldering paste, silver paste, graphite/ carbon-containing paste, etc.) which serves as each negative electrode collector 6 is printed over the entire surface of a base material member 3 to a thickness of approximately 3 microns and this agent becomes thermosetting. Next, carbon which serves as a negative electrode active material 7 is printed thereon excluding a triangular portion 5 to a thickness of approximately 50 microns and this carbon is hardened by means of electron beams. And a high- molecular solid electrolyte which serves as a separator 8 is printed in such a manner as to cover the negative electrode active material and this solid electrolyte is hardened using electron beams. Thereafter, a positive electrode active material 9 is printed and hardened using electron beams. Next, after printing a conductive agent 10 on the positive electrode active material 9 excluding the triangular portion 5 and hardening it, a resin paste 11 is printed, thus a battery composed of a series of unit cells is obtained. By arbitrarily separating and severing such battery, assembling and serial/parallel connecting of the battery elements that could provide a high productivity and would produce no defects can be easily performed.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art In a conventional battery, FIG. 6 shows a window frame-shaped adhesive material 2 (indicated by a dotted line area in the figure) thermally bonded to the peripheral area of the inner surface of a positive electrode current collector 1. It is a perspective view when the positive electrode active material 3 is applied to the inner collector surface afterward. Figure 7
Shows the cross-sectional state of the AA 'part in FIG. In FIG. 8, after the window frame-shaped adhesive material 5 is thermally bonded to the peripheral area of the upper surface of the negative electrode current collector 4, metallic lithium as the negative electrode active material 6 is pressure bonded to the inner area of the negative electrode current collector 4, and FIG. 3 is a perspective view when a polymer solid electrolyte as a separator 7 is applied on the upper surface of the negative electrode active material 6. FIG. 9 shows a cross-sectional view taken along the line BB ′ of FIG. 8. In order to prevent a short circuit between the positive electrode active material 3 and the negative electrode active material 6 at an inner corner of the adhesive, the width of the adhesive 5 is equal to that of the adhesive 2. Is smaller than the width of. The negative electrode made of the negative electrode current collector 4 and the positive electrode made of the positive electrode current collector 1 thus produced are overlapped with each other, and the adhesive material 2 and the adhesive material 5 are adhered to each other to hermetically seal the inside of the battery.

However, when a large number of batteries are to be produced, there is a problem in continuous production such that the production cost increases if the batteries are produced one by one. In addition, alignment becomes difficult when processing the battery. Further, when the batteries are connected in series or in parallel, it is necessary to assemble the batteries after they are manufactured, which deteriorates productivity. In addition, an extra connecting member is required for connection. Further, in order to reduce the battery thickness, it is necessary to reduce the thickness of the current collector. However, for example, a current collecting metal having a thickness of 10 μm to 20 μm is extremely difficult to handle, and it is difficult to handle it in continuous production. It may be damaged by.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to facilitate assembly of battery elements and series / parallel connection without causing productivity and defects. To establish a structure of a thin battery and a manufacturing method thereof. Further, various battery shapes can be obtained only by changing the shape of the printing plate, and it is possible to obtain a battery in which the batteries are vertically and horizontally connected by a base material with a fixed pattern.

[0005]

Means for Solving the Problems The present invention achieves the above object, and for batteries, conductive materials such as a positive electrode active material, a separator, a negative electrode active material, and a conductive paste as a current collector are used. A battery element composed of a printable battery component such as an agent, a positive electrode conductive agent and a negative electrode conductive agent as the current collector are separated by an insulator, a plurality of sets of battery elements are included, When the battery elements are connected in parallel, the insulators are connected to each other at the outer side of the insulator located outside the outer periphery of the active material or at the through holes, and the battery elements are connected in series. In this case, a positive electrode is formed on one surface of the conductive material and a negative electrode is formed on the other surface, or at the outside of the insulating material located outside the outer periphery of the active material or the through hole portion of the insulating material on the conductive material surface. That the conductive agents are connected to each other, the conductive agent The substrate outermost, for example a resin film, particularly humidity resistance resin film are disposed,
A through hole is provided in a part of the base material to serve as a current collector terminal, the base material is a composite of a metal foil and a resin film, and at least a part of the metal foil constituting the base material is conductive. Forming a terminal portion by exposing the outer surface of the metal foil on at least a part of the outer surface of the base material to form a terminal portion, and between the part of the conductive agent, that is, the current collecting terminal portion. -For forming the gap portion, and for the manufacturing method, a step of printing a conductive agent as a current collector on the substrate, a step of printing or disposing a negative electrode active material, a step of printing or disposing a separator, A step of printing a positive electrode active material, a step of printing a conductive agent as a current collector of the counter electrode, and a step of disposing a base material of the counter electrode; and a step of curing each of the battery constituent materials after printing. , After printing the conductive agent as the current collector of the counter electrode, Arranging or printing an insulator, further repeating each of the above steps, connecting the battery elements in parallel or in series, respectively, using a resin film or resin paste as the insulator, in series connection or parallel connection of the insulator Connection is made outside the outer periphery or on the surface of the conductive material at a portion without an insulator. In the above connection, when a resin film is used, holes are provided in advance.
In the case of a strike, a feature is that an unprinted portion is provided in a part by printing, and these solve the above problems.

[0006]

The feature of the present invention is that the conductive material such as conductive fine powder (metal, metal carbide, metal sulfide, carbon, graphite, etc.) can be printed as a collector (claim 1 and 10). For example, it can be formed into an arbitrary shape (for example, only by changing the pattern of the printing plate) by printing it on a base material in the form of a paste; silver paste, etc., and a series of fixed patterns. Can be provided on the base material. Further, a negative electrode active material (or positive electrode active material), a separator, a positive electrode active material (or negative electrode active material) and an insulator are sequentially printed on the upper surface of the conductive agent to continuously form a battery element with a constant pattern. Can be formed. According to the second to fourth and twelfth to fourteenth aspects, the respective battery elements can be easily connected in parallel or in series simply by changing the shape pattern of the insulator on the same surface. According to claim 5, deterioration of the battery element due to the influence of moisture can be prevented. In addition, handling of the battery becomes easy, and the mechanical strength of the battery is increased while having flexibility. Further, according to claims 6 to 8, the battery terminals can be easily formed without using a special member, and the battery production on a series of base materials is facilitated. Further, according to claim 9, when an overcurrent flows in the thin battery, the fuse parts are melted and connected in parallel, the influence on other battery elements can be reduced. Conventionally, since the current collector portion is arranged to be thin, the fuse portion is cut and unusable at the time of handling, but in the present invention, printing facilitates processing and enhances productivity. According to claim 11, a polymer compound contained in an active material, a separator, a conductive agent, an insulator or the like is dried or crosslinked by heat, UV irradiation, or electron beam irradiation to enhance the mechanical strength of a printed film. Then, other battery component parts can be printed on the upper surface. Further, by doing so, it is possible to prevent a short circuit between the battery elements and a short circuit due to the deterioration of the separation function due to the diffusion between the battery elements (for example, the permeation of the separator component into the positive electrode active material).

[0007]

【Example】

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a card-shaped thin battery 1 having a thickness of about 0.5 mm and a voltage of 3 V (two parallel connection). FIG. 2 shows the thin battery in a fixed pattern on a series of base materials. Fig. 7 shows a manufacturing procedure at the time of manufacturing, and shows a perspective view when each battery element is formed with a base material on the negative electrode side as a base. In addition, in FIG. 2, the formation state of each step is shown for each pattern in order to make a series of formation states easy to understand. Further, the dotted line portion shows a cutting target area for obtaining individual card-size thin battery cells by separating in the final step, and the thin battery cells are hermetically sealed on the inner side slightly from the dotted line. As the base material 3, a modified PP resin film 4 whose outer surface is coated with a metal 2 (for example, aluminum, copper, nickel, stainless steel, etc.) is used, and the modified PP resin film 4 is removed in a triangular shape at one corner thereof. (To be used later as a connection terminal portion) was formed (for example, removed by laser irradiation). Conductive agent (for example, solder paste, silver paste, graphite carbon) as the negative electrode current collector 6 is contained on the entire inner surface including the portion 5 (excluding the above-mentioned scheduled area for airtight seal). (Paste, etc.) to a thickness of about 3 μm (screen printing, metal mask printing, pad printing, etc.) and heat cured. Further, a carbon as the negative electrode active material 7 was printed (screen printing, metal mask printing, etc.) with a thickness of about 50 .mu.
Next, a polymer solid electrolyte as a separator 8 having a thickness of about 10 μm is formed so as to cover the negative electrode active material 7 (prevent short circuit).
Screen printing was carried out and electron beam curing was carried out. Further, a lithium / cobalt oxide mixture as a positive electrode active material 9 was printed on the surface of the separator slightly smaller than the separator 8 to a thickness of about 150 μm with a metal mask and electron beam cured.

Next, a conductive agent 10 (positive electrode current collector) was printed on the positive electrode active material 9 except for the triangular region 5 and cured. Next, a resin paste 11 (which may be in the form of a film) as an insulator, which is slightly larger than the conductive agent 10, is used in an amount of about 10.
Printed to a μ thickness and dried. Further, a conductive agent 6'as a negative electrode current collector was printed thereon and cured. By repeating these steps, a thin battery in which two battery elements are connected in parallel was manufactured.

FIG. 3 is a cross-sectional view of two parallel-connected thin type batteries.
The state of the AA 'part of FIG. 1 is shown. Actually about 0.5m
m, and the shape of the end portion is not distorted as shown in FIG. Since it is expanded to several tens to several hundreds of times, the airtight seal between the battery element at the end and the modified PP resin films 4, 4'on the negative electrode side and the positive electrode side (heat is generated by a heat roll or a heat plate). Fusing) appears to hang down. It should be noted that the risk of short circuit is reduced if the insulator is partially printed on the portion B before the conductive agent 10 is printed. As shown in FIG. 3, after the battery element fabrication was repeated twice, the conductive agent 10 ′ was printed,
After curing, a base material 3 '(the same base material as the negative electrode side base material 3 is used as the positive electrode side base material 3') is arranged on the base material 3 '.
Then, the outer surface of the base material 3'is pressed (passing the base material between the rolls) to discharge the gas in the battery, and the conductive agent 10 'and the positive electrode side metal 2'are connected by the triangular portion 5'. The triangular portion 5'is provided at a position symmetrical with the triangular portion 5 on the negative electrode side. Further, by slightly changing the sizes of the positive electrode side metal 2 ′ and the negative electrode side metal 2, it is possible to prevent a short circuit at the end of the thin battery.

(Embodiment 2) FIG. 4 shows a thin unit cell 12 (having a side of about 20 mm) having a thickness of about 0.5 mm and a voltage of 6 V (two series connection).
mm and 13 mm squares are patterned and connected at the base material portion. 5) is a cross-sectional view of a thin battery having a predetermined shape (in the case of a card size, a plurality of batteries are connected.
The size of separation from the series of batteries shown in FIG. For example, 4 in the width direction and 4 in the length direction.
6 pieces are connected. ) Is composed of the unit cell 12.

A plurality of holes are provided in the central portion of the resin film 14 of the base material 13 (having the same structure as the base material 3) to expose the metal 13 'surface. In this operation, the resin film 14 having holes previously formed on the metal surface may be adhered. Next, the negative electrode conductive agent 15 is printed and cured except for the adhesive seal area. Next, the negative electrode active material 16 is printed on it and cured. Further, a separator 17 and a positive electrode active material 18 are printed and cured thereon. Next, a positive electrode conductive agent 19 is printed on the positive electrode active material 18 and cured. Further, the insulator 20 is provided with holes on it, and is printed and cured so as to include the above battery elements. Next, a negative electrode conductive agent 15 'was printed and cured thereon, and a negative electrode active material 16' was further printed and cured. The insulator 20 is omitted, and the negative electrode active material 1 is directly provided on the positive electrode conductive agent 19.
6'may be printed, but the provision of the insulator 20 can prevent an internal short circuit. On top of that, a separator 17 ',
The positive electrode active material 18 ′ and the positive electrode conductive material 19 ′ were printed and cured. Next, the resin film 14 ′ surface of the positive electrode substrate 13 ′ was placed, and the metal 13 ″ surface and the positive electrode conductive agent 19 ′ surface were adhered. Furthermore, these were passed between pressure rolls, The gas is discharged, and the resin film surfaces in the peripheral area are adhered to each other by a heating roll or a heating plate to seal the inside of the battery.
I did.

The metal on one side of the battery thus hermetically sealed is hermetically sealed in an arbitrary shape by a laser or the like.
And separated electrically from the other battery groups. Next, the base material was cut by another method (for example, a press, a die-roll blade, a Thomson blade, a forming blade, a cutter blade, etc.) in the metal separation gap. As shown in FIG. 4, at the end of the battery, the resin film is protruded to the outside so that the metals of the positive electrode base material and the negative electrode base material do not short-circuit. This was done by further hot pressing the peripheral area after separation.

[0013]

The present invention has the following effects. (1) Batteries of various sizes and capacities can be obtained by arbitrarily separating and cutting a battery consisting of a series of unit cells. (2) In a series of battery manufacturing steps, batteries connected in series or in parallel can be continuously formed simply by changing the shape of the printing plate in each step. (3) By using a resin film as the base material, it is not necessary to dispose the adhesive specially, the process can be omitted, and there is no deviation due to the alignment accuracy, and the moisture resistance is high. (4) Series connection or parallel connection can be performed without short circuit inside the battery. (5) By printing a conductive agent, a collector surface of various shapes can be obtained, and connection with a collector terminal is facilitated through a resin film that enhances airtightness, particularly moisture resistance. (6) Connection between the conductive agents of the same polarity can be achieved simply by printing on them. (7) The base material has three layers, and the metal is arranged in the central layer, so that there is no damage at the bent portion of the metal layer when the battery is bent, and the positive electrode at the end of the battery is better than in the case of two layers. A short circuit between the metal of the side base material and the metal of the negative electrode side base material can be prevented by fusing the resin film. Further, it is possible to prevent an inadvertent short circuit on the outer surface of the battery. Further, the outer resin film can be designed. Further, a hole is formed in a part of the outer resin film, and the exposed metal surface can be used as a terminal. Note that the present invention is not limited to those shown in the examples, but the shape and number of battery elements, the thickness of constituent materials, the number of layers, the fuse shape, and the electrolytic solution when an electrolytic solution is used. And the like (the separator may be printed and cured, and then added and impregnated. An excess electrolytic solution may be mixed in advance in the separator). Rather, it is changed according to the application.

[Brief description of drawings]

FIG. 1 is a perspective view of a card-sized thin battery according to the present invention.

FIG. 2 is a perspective view showing a formation state surface of each step in manufacturing a series of patterned batteries according to the present invention.

FIG. 3 is a cross-sectional view of thin batteries connected in parallel inside the battery according to the present invention.

FIG. 4 is a cross-sectional view of thin batteries connected in series inside the battery according to the present invention.

FIG. 5 is a perspective view showing a series of batteries including a plurality of unit cells according to the present invention.

FIG. 6 shows a perspective view of a conventional positive electrode current collector.

FIG. 7 shows a cross-sectional view of FIG.

FIG. 8 shows a perspective view of a conventional positive electrode current collector.

9 shows a cross-sectional view of FIG.

[Explanation of symbols]

3, 13 Base material 2, 2 ', 13, 13', 13 "Metal 4, 4 ', 14, 14' Resin film 6, 6 ', 10, 10' Conductive agent 7, 7 ', 16, 16' Negative electrode Active material 8, 8 ', 17, 17' Separator (polymer solid electrolyte) 9, 9 ', 18, 18' Positive electrode active material 11, 20 Insulator 12 Unit cell

Claims (14)

[Claims] 1. A thin battery comprising a battery element composed of a positive electrode active material, a separator, a negative electrode active material, and a conductive agent as a current collector. 2. The thin battery according to claim 1, wherein the positive electrode conductive agent and the negative electrode conductive agent as the current collector are separated by an insulator, and a plurality of sets of battery elements are included. 3. When the battery elements are connected in parallel, the insulating material is such that the conductive agents are connected to each other outside the outer periphery of the active material or at the through hole portion of the insulating material. The thin battery according to claim 2. 4. When the battery elements are connected in series, a positive electrode is formed on one surface of the conductive material and a negative electrode is formed on the other surface, or the outside of an insulator positioned outside the outer periphery of the active material. 3. The thin battery according to claim 1, wherein the conductive agents are connected to each other at a through hole portion of the insulator on the conductive agent surface. 5. The thin battery according to claim 1, wherein a base material, for example, a resin film, particularly a moisture resistant resin film, is disposed on the outermost side of the conductive agent. 6. The thin battery according to claim 5, wherein a through hole is provided in a part of the base material to serve as a current collecting terminal portion. 7. The thin battery according to claim 5, wherein the base material is a composite of a metal foil and a resin film. 8. A terminal portion is formed by exposing at least a part of a metal foil constituting the base material with a conductive agent, and / or exposing the outer surface of the metal foil to at least a part of the outer surface of the base material. The thin battery according to claim 5, wherein: 9. A fuse part is formed between a part of the conductive material, that is, a current collecting terminal part.
9. The thin battery according to any one of 8 to 8. 10. A step of printing a conductive agent as a current collector on a substrate, a step of printing or arranging a negative electrode active material, a step of printing or arranging a separator, a step of printing a positive electrode active material, A method of manufacturing a thin battery, which further comprises a step of printing a conductive agent as a current collector of the counter electrode and a step of disposing a base material of the counter electrode. 11. The method of manufacturing a thin battery according to claim 10, further comprising a step of curing each of the battery constituent materials after printing. 12. A printing method using a conductive agent as a current collector for the counter electrode, arranging or printing an electric insulator, and repeating the above steps to connect the battery elements in parallel or in series. The method for manufacturing a thin battery according to claim 10. 13. A resin film or a resin paste is used as the insulator, and when connected in series or in parallel, the insulator is connected outside the outer periphery of the insulator or on the surface of the conductive material without the insulator. The method for manufacturing a thin battery according to claim 12. 14. The connection according to claim 13, wherein a hole is provided in advance when a resin film is used, and an unprinted portion is partially provided by printing in the case of a resin paste. Thin battery manufacturing method.