JPH076771A - Film battery and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain a film battery, in which the lowering of performance to a bending load is reduced. CONSTITUTION:Metal foils 4, 5 working as a collector and a battery jar are arranged on and under a generating element, which is formed by laminating a positive electrode active material 1, an electrolyte layer 2 and a negative electrode active material 3. After assembling a thin battery, to which a peripheral edge of this collector working as a battery jar is adhered through a frame- like adhesive resin 6, whole of the top surface of any one of the upper and the lower metal foils 4, 5 working as a collector and a battery jar is heated for welding again by a corrugated heating plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film battery used in the field of small electronic devices such as smart cards.

[0002]

2. Description of the Related Art Recently, as microelectronics has been used, as represented by a memory-backup power supply for various electronic devices, the battery is housed in the electronic device and integrated with electronic elements and circuits. Miniaturization, weight reduction,
There is a demand for thinning and high energy density. In the field of primary batteries, small and lightweight batteries such as lithium batteries have already been put into practical use, but their fields of use are limited.
Therefore, many research institutes are still studying film batteries that are smaller, lighter, and thinner than conventional batteries.

Conventionally, a thin battery of this type has a structure as shown in FIGS. 3 and 4, and has a positive electrode active material layer 1, an electrolyte layer 2 and a negative electrode active material layer 3 stacked on top of and below a power generating element. The positive electrode collector / cumulative vessel 4 and the negative electrode collector / cumulative vessel 5 were arranged in the above, and the adhesive resin 6 and the current collector / cumulative vessels 4 and 5 were integrated. In such a conventional configuration, particularly when the number of bending loads is large, the internal contact state of the electrode interface is deteriorated and the internal resistance of the battery is increased to deteriorate the performance. At the interface of the body / battery case 4, gas is mixed from the outside due to partial peeling and the internal resistance of the battery similarly rises, causing performance degradation.

[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 provide a film battery whose performance is not significantly deteriorated even with a bending load.

[0005]

The present invention provides a positive electrode active material,
A metal foil, which is a collector and a container, is arranged above and below a power generation element in which an electrolyte layer and a negative electrode active material are layered, and the peripheral portion of the collector and the container is surrounded by a frame-shaped adhesive resin. A thin battery that is adhered, characterized in that after assembly, the upper surface of at least one side of the upper and lower metal foils, which are the current collector and the battery case, are heat-welded to the entire surface again by means of a knurled hot plate to weld them It solves the problem.

Further, the jagged pattern pitch of the hot plate is set to 0.
Battery area is 1 cm by setting 5 mm to 1.5 mm
It solves the above problems in a wide range from small batteries to large batteries.

Examples of the above-mentioned electrolyte of the present invention include those having a polyfunctional hydroxyl group and an ether which is crosslinked by an ether bond with a diacrylate. Next, as the ionic compound contained in the electrolyte, for example, LiClO4, LiSCN, LiAsF6, LiCF3SO3, L
Examples thereof include Li salts such as iCF3SO2, but are not particularly limited. Next, as the non-aqueous electrolytic solution contained in the electrolyte, cyclic esters such as propylene carbonate and ethylene carbonate, tetrahydrafuran or a derivative thereof, 1,3-dioxolane, 1,2-dimethoxyethane Examples thereof include ethers and the like, or a mixture of two or more thereof, but are not limited thereto. Next, examples of the active material forming the positive electrode include metal oxides such as manganese, vanadium, and cobalt, but are not particularly limited. Next, examples of the active material that constitutes the negative electrode include carbonaceous materials such as carbon, lithium metal, lithium-aluminum, lithium-lead, lithium-tin, lithium-gallium, and lithium alloys such as wood alloys. However, it is not limited thereto. Next, materials such as aluminum, stainless steel, and titanium are preferable for the positive electrode current collector, and materials such as stainless steel, iron, nickel, and copper are preferable for the negative electrode current collector, but the material is not particularly limited to these. .

[0008]

According to the present invention, the electrode interfacial contact force inside the battery and the adhesive resin 6 and the collector / battery container 4 at the sealing portion of the battery at the outer periphery are
Since the interfacial adhesive strength is maintained, the internal impedance of the battery does not increase and the performance does not deteriorate even when a bending load is applied. The same effect can be expected even with a small battery having a battery area of 1 cm 2.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are a cross-sectional view and a top view of a film battery according to an embodiment of the present invention, in which 1 is a positive electrode active material containing manganese dioxide as a main component, and 2 is polyethylene oxide to which lithium perchlorate is added. Polymer solid electrolyte 3 is a negative electrode active material made of lithium. The current collectors 4 and 5 made of stainless steel are arranged above and below these power generating elements, and the peripheral portions of the stainless steel current collectors 4 and 5 are adhered to each other via a polypropylene-based thermoadhesive resin 6. After the above-mentioned assembling process, a Teflon-coated Teflon-coated metal wire having a width of 1 mm and a pitch of 1 mm from the upper surface and the lower surface is used.
By thermocompression bonding at 0 ° C. for 1 second, a film battery having high bending resistance can be produced.

[0010]

The present invention has the following effects. According to claim 1, the electrode interfacial contact force inside the battery and the interfacial adhesive force between the adhesive resin 6 at the sealing portion of the outer periphery of the battery and the current collector / battery 4 are maintained, so that the battery internal impedance is maintained even when a bending load is applied. -There is no possibility that the dance will rise and the performance will decline. Further, according to claim 2, the same effect can be expected even with a small battery having a battery area of 1 cm 2. FIG. 5 shows the above effects by comparing the battery characteristics after the bending test according to JIS standard X6311 for prepaid cards. In the conventional battery, a decrease in voltage and a decrease in capacity due to an increase in impedance due to a decrease in interfacial contact inside and outside the battery are observed, but the battery of the present invention maintains the nominal capacity.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a structure of a film battery according to an embodiment of the present invention.

FIG. 2 is a top view showing a structure of a film battery according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view showing the structure of a film battery having a conventional structure.

FIG. 4 is a top view showing a structure of a film battery having a conventional structure.

FIG. 5 is a graph comparing the discharge characteristics of the battery of the present invention and the conventional battery after the bending test.

[Explanation of symbols]

 1 Positive Electrode Active Material 2 Electrolyte 3 Negative Electrode Active Material 4 Positive Electrode Current Collector 5 Negative Current Collector 6 Sealing Resin

Claims (3)

[Claims] 1. A metal foil, which is a collector and a container, is arranged above and below a power generation element in which a positive electrode active material, an electrolyte layer, and a negative electrode active material are stacked in layers, and a peripheral portion of the collector and the container is disposed. A thin battery formed by adhering via a frame-shaped adhesive resin, characterized in that at least one entire upper surface thereof has a jagged uneven shape. 2. A metal foil, which is a collector and a container, is disposed above and below a power generation element in which a positive electrode active material, an electrolyte layer, and a negative electrode active material are layered, and a peripheral portion of the collector and battery is arranged. After assembling a thin battery formed by adhering it through a frame-shaped adhesive resin, heat is applied to the entire surface again from the upper surface of at least one side of the upper and lower metal foils, which are the current collector and the battery case, by a jagged heat plate. A method for manufacturing a film battery, which comprises welding. 3. The jagged pattern pitch of the hot plate is
The film battery manufacturing method according to claim 2, wherein the film battery has a thickness of 0.5 mm to 1.5 mm.