JP2003100350A - Cell and its making method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high quality cell made in a simple manufacturing process, whereas the cell has a multilayer electrode ensuring a large electrode area, and to provide a making method of the cell. SOLUTION: The making method of the cell comprises the steps of: forming a first sheet which has a mixture layer containing a negative electrode active material on either side of a first current collector; forming a second sheet which has a plurality of mixture layer areas containing a positive electrode active material alternately with areas uncoated with the mixture layer on the chief side of a second current collector; covering the mixture-uncoated area and both the end areas of the mixture-coated areas adjacent to the mixture-uncoated area on the chief side of the second sheet, with an insulation film; placing an electrolyte film on the chief side of the second sheet or on the either side of the first sheet; forming and element where both the mixture layers on both the sides of the first sheet are placed between one mixture layer area and the neighboring mixture layer area on the chief side of the second sheet by folding the second sheet inwardly on the mixture-uncoated area and interposing the electrolyte film between one mixture layer of the first sheet and one mixture layer area of the second sheet; and covering the elements with a facing film.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a battery including a positive electrode, a negative electrode, and an electrolyte film.

[0002]

2. Description of the Related Art As electronic devices become cordless and portable, batteries used as driving power sources for various electronic devices, especially secondary batteries, are required to be smaller and lighter. For these electronic devices, nickel cadmium secondary batteries, lead batteries, and non-aqueous electrolyte batteries using an active material capable of inserting and extracting lithium, so-called lithium batteries, and the like are used.

Of these batteries, lithium-based batteries such as lithium batteries and lithium-ion batteries have the advantages of high battery voltage, high energy density, low self-discharge and excellent cycle characteristics. Therefore, it is being used as a practical battery.

[0004]

In recent years, lithium batteries have been required to have a battery shape adapted to the shape of electronic equipment. For example, it is required to have a sheet-shaped or strip-shaped battery shape that can be mounted on an electronic device such as hardware.

A liquid battery using a non-aqueous electrolyte as an electrolyte uses a metal can as an exterior material in order to prevent liquid leakage and ensure safety, so the battery shape is not variable. For this reason, it is difficult to adapt the shape of the liquid battery to the shape of the electronic device, and it is not possible to make the battery shape into a sheet shape or a strip shape, for example.

Therefore, a solid electrolyte battery using a solid electrolyte which does not cause liquid leakage as an electrolyte and a laminate film as an exterior material has been put into practical use. Since the laminate film used as the solid electrolyte and the exterior material is excellent in flexibility, the solid electrolyte battery including them is also excellent in flexibility, and the battery shape can be made into a sheet shape or a strip shape relatively easily. .

By the way, considering the multi-functionality of the hardware, it is indispensable to increase the capacity of the battery, and it is necessary to secure a wide area of the electrode provided with the mixture layer and the current collector. In the case of an electrode having a single-layer structure, in order to achieve a desired battery capacity, it is necessary to have a large electrode area in one plane. Furthermore, the battery exterior needs to have an area equal to or larger than that of the electrodes. Therefore, if the electrode area of the electrode having a single-layer structure is increased, the use is limited and the manufacturing cost is increased. Therefore, a mixture layer is formed, for example, by stacking rectangular current collectors to form a multi-layered electrode, a wide electrode area is secured, a desired battery capacity is achieved, and a battery outer shape is small. It is proposed that

However, when an electrode having a multi-layer structure formed by stacking current collectors is used, various steps such as cutting out leads for each current collector and welding and connecting the leads are required at the time of manufacturing the battery, and the battery structure However, the battery manufacturing process becomes complicated.

Further, in the case of an electrode having a multi-layer structure, when a local load is applied to the end of the electrode, the solid electrolyte is destroyed at the end of the electrode, or powder is removed to cause a short circuit, resulting in a product yield. There is a problem of being bad.

The present invention has been proposed in view of such a conventional situation, and provides a high quality battery with a simple manufacturing process even though it has an electrode having a multilayer structure capable of ensuring a large electrode area. It is an object to provide a battery that can be manufactured and a manufacturing method thereof.

[0011]

In order to achieve the above-mentioned object, the battery according to the present invention has a structure in which either the positive electrode active material or the negative electrode active material is contained on both surfaces of the first current collector. The first sheet provided with the agent layer and the main surface of the second current collector,
A mixture layer containing the other of the positive electrode active material and the negative electrode active material, the second sheet provided with a plurality of mixture layers not covered with the mixture, and an electrolyte film, and the main portion of the second sheet. The surface side covers the mixture layer uncoated portion, the end portion of the one mixture layer on the mixture layer uncoated portion side, and the end portion of the other mixture layer on the mixture layer uncoated portion side. As described above, the insulating film is disposed, and the mixture layer provided on both surfaces of the first sheet is bent at the portion not coated with the mixture by the second sheet through the electrolyte film. The above second
The element which is sandwiched between one mixture layer and the other mixture layer provided on the main surface of the sheet, is covered with an exterior film.

In the battery constructed as described above, the insulating film is provided on the main surface side of the second sheet, on which the mixture layer is not applied,
Since it is arranged so as to cover the end of one mixture layer on the side not mixed with the mixture layer and the end of the other mixture layer on the side not coated with the mixture layer, the second sheet is combined. Even when a local load is applied to the bent part that is bent at the agent-uncoated part, the positive electrode mixture layer is prevented from peeling or rubbing, in other words, powder falling is prevented. There is. That is, in this battery, the occurrence of a short circuit due to powder falling is prevented.

Further, the method for producing a battery according to the present invention comprises the steps of forming a mixture sheet containing a positive electrode active material or a negative electrode active material on both surfaces of the first current collector. Forming step and forming a plurality of mixture layers containing the other of the positive electrode active material and the negative electrode active material on the main surface of the second current collector through a mixture uncoated portion of the second sheet In the forming step, on the main surface side of the second sheet, the mixture layer uncoated portion, the end of the one mixture layer on the mixture layer uncoated portion side, and the other mixture layer are mixed. An insulating film disposing step of disposing an insulating film so as to cover the end portion on the agent layer uncoated portion side,
An electrolyte film arranging step of arranging an electrolyte film on the main surface of the second sheet or both surfaces of the first sheet, and a combination of the steps provided on both surfaces of the first sheet via the electrolyte film. A device in which the agent layer is sandwiched between one agent layer and another agent layer provided on the main surface of the second sheet by bending the second sheet at the agent-uncoated portion. And a step of covering the above element with an exterior film.

According to the method of manufacturing a battery configured as described above, the insulating film is provided on the main surface side of the second sheet, the mixture layer non-applied portion, and the mixture layer non-applied to one mixture layer. Since the second sheet is disposed so as to cover the end on the part side and the end of the other mixture layer on the side not mixed with the mixture layer, the second sheet is bent at the part not coated with the mixture. The positive electrode material mixture layer 22 is peeled off or rubbed even if a local load is applied to
In other words, it is possible to prevent the powder from falling off. That is, according to this battery manufacturing method, it is possible to manufacture a battery in which the occurrence of a short circuit due to powder falling is prevented.

Further, the battery according to the present invention comprises: a first sheet provided with a mixture layer containing either a positive electrode active material or a negative electrode active material on both surfaces of the first current collector; A second sheet in which a plurality of mixture layers containing either the positive electrode active material or the negative electrode active material on the main surface of the second current collector are provided via the mixture uncoated portion, and the electrolyte film. And the first
A first lead is provided at one end of the sheet of No. 1 to extend to the outside of the exterior film, and one end of the second sheet is provided to extend to the outside of the exterior film. Two leads are provided, and an insulating film is provided on at least one main surface of the first lead and / or a main surface of the second lead, and the first film is provided via the electrolyte film.
The mixture layer provided on both sides of the second sheet, and the other mixture layer provided on the main surface of the second sheet by bending the second sheet at the mixture-uncoated portion. The element sandwiched between the mixture layer and the mixture layer is packaged with a packaging film.

In the battery constructed as described above, since the insulating film is provided on at least one main surface of the first lead and / or the main surface of the second lead, the first lead and the first lead The difference in thickness between the second lead and the element is corrected to prevent the stress from concentrating locally on the portion where the difference in thickness occurs. Therefore, in this battery, the solid electrolyte film is prevented from being physically destroyed even if a load is applied when the device is vacuum-sealed with the exterior film, for example.

Further, the method for producing a battery according to the present invention comprises the steps of forming a mixture sheet containing a positive electrode active material or a negative electrode active material on both surfaces of a first current collector. Forming step and forming a plurality of mixture layers containing the other of the positive electrode active material and the negative electrode active material on the main surface of the second current collector through a mixture uncoated portion of the second sheet Forming Step: Providing a first lead at one end of the first sheet so as to extend to the outside of the exterior film, and extending at one end of the second sheet to the exterior of the exterior film So that the second lead is provided, and an insulating film is provided on at least one main surface of the first lead and / or the main surface of the second lead, and An electrolyte film disposing step of disposing an electrolyte film on the main surface or both surfaces of the first sheet, and Through the electrolyte film, the first
The mixture layer provided on both sides of the sheet of No. 2 is bent by bending the second sheet at a portion not coated with the mixture, and one mixture layer provided on the main surface of the second sheet and another layer The method is characterized by including an element forming step of forming an element sandwiched with a mixture layer and a step of covering the element with an exterior film.

According to the method of manufacturing a battery configured as described above, by disposing the insulating film on at least one main surface of the first lead and / or the main surface of the second lead, the first It is possible to correct the thickness difference between the element and the second lead and the second lead, and prevent the stress from being locally concentrated on the portion where the thickness difference occurs. Therefore, according to this battery manufacturing method, it is possible to manufacture a battery in which the solid electrolyte film is prevented from being physically destroyed even if a load is applied when the device is vacuum-sealed with the exterior film, for example. You can

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION A battery to which the present invention is applied will be described below in detail with reference to the drawings.

As shown in FIG. 1, the battery 1 has an element 3 including a plurality of first sheets which will be the negative electrode 10, a second sheet which will be the positive electrode 20, and a solid electrolyte film 2. . Further, in this battery, the element 3 is packaged with a packaging film 4.

As shown in FIG. 2, the first sheet, that is, the negative electrode 10 is formed on a plurality of substantially rectangular negative electrode current collectors 11 (first current collectors) and both surfaces of the negative electrode current collector 11. And a negative electrode mixture layer 12 containing a negative electrode active material. A negative electrode lead 14 is provided at one end of the negative electrode current collector 11.

Specifically, the negative electrode 10 includes a negative electrode mixture layer 12a formed on one surface of one negative electrode current collector 11α and a negative electrode mixture layer 12a formed on the other surface of one negative electrode current collector 11α. Agent layer 1
2b, a negative electrode mixture layer 12c formed on one surface of the other negative electrode current collector 11β, and a negative electrode mixture layer 12d formed on the other surface of the other negative electrode current collector 11β. In the negative electrode 10, one negative electrode lead 14a and the other negative electrode lead 14b are integrated.

As shown in FIG. 3, the second sheet, ie, the positive electrode 20, has a strip-shaped positive electrode current collector 21 (second current collector).
And a positive electrode mixture layer 22 formed on the main surface of the positive electrode current collector 21 and containing a positive electrode active material. This positive electrode mixture layer 22
Are intermittently applied to the positive electrode mixture containing the positive electrode active material, and a plurality of the positive electrode mixtures are provided through the positive electrode mixture non-application portion 23. A positive electrode lead 24 is provided at one end of the positive electrode current collector 21.

The positive electrode 20 is specifically, a positive electrode current collector 21.
Of the first electrode adjacent to the uncoated portion 23a where the positive electrode mixture layer 22 is not formed at one end in the longitudinal direction of the
Of the positive electrode material mixture layer 22a, the first positive electrode material mixture layer 22a opposite to the uncoated portion 23a side, and the uncoated portion 23b and the uncoated portion 23b adjacent to the first positive electrode material mixture layer 22a side. The second positive electrode mixture layer 22b and the second positive electrode mixture layer 22 adjacent to the side
The uncoated portion 2 adjacent to the uncoated portion 23b side of b.
3c, the third positive electrode mixture layer 22c adjacent to the side opposite to the second positive electrode mixture layer 22b side of the uncoated portion 23c, the side opposite to the uncoated portion 23c side of the third positive electrode mixture layer 22c 23d adjacent to the third positive electrode mixture layer 2 of the uncoated portion 23d
A fourth positive electrode mixture layer 22d adjacent to the side opposite to the 2c side,
The fourth positive electrode mixture layer 22d is provided with an uncoated portion 23e adjacent to the side opposite to the uncoated portion 23d side.

In the element 3, as shown in FIG. 1, the negative electrode material mixture layers 12 provided on both surfaces of the negative electrode 10 with the solid electrolyte film 2 interposed therebetween have the positive electrode 20 bent at the uncoated portion 23. One positive electrode material mixture layer 2 provided on the main surface of the positive electrode 20 by
2 and another positive electrode mixture layer 22.
That is, the negative electrode mixture layers 12a and 12b are bent in the valley fold direction at the uncoated portion 23b of the positive electrode 20, so that one positive electrode mixture layer 22a provided on the main surface of the positive electrode 20 and another positive electrode. It is sandwiched between the mixture layer 22b. Further, the negative electrode mixture layers 12c and 12d are bent in the valley fold direction at the uncoated portion 23d of the positive electrode 20, so that one positive electrode mixture layer 22c provided on the main surface of the positive electrode 20 and another positive electrode. Mixture layer 22d
It is sandwiched between and.

That is, in this battery 1, the positive electrode 2 in which a plurality of positive electrode mixture layers 22 are formed on the main surface of one positive electrode current collector 21.
0 and a plurality of negative electrodes 10 having the negative electrode mixture layers 12 formed on both surfaces of the negative electrode current collector 11 are alternately laminated with the solid electrolyte film 2 interposed therebetween, and a wide electrode area is secured. Although the electrode having a possible multi-layer structure is provided, the lead can be drawn from the positive electrode 20 only from one end of the positive electrode 20, and the battery structure and the battery manufacturing process are simple.

In this battery 1, in the positive electrode 20, as shown in FIG. 4, the main surface side of the positive electrode 20 is the uncoated portion 23 of the positive electrode mixture layer and the positive electrode mixture layer 22 of one positive electrode mixture layer 22. The insulating film 25 is arranged so as to cover the end of the layer on the uncoated portion 23 side and the end of the positive electrode mixture layer of the other positive electrode mixture layer 22 on the uncoated portion 23 side.

Specifically, for example, the uncoated portion 23b of the positive electrode mixture layer, the end of the positive electrode mixture layer 22a on the side of the uncoated portion 23b of the positive electrode mixture layer, and the positive electrode of the other positive electrode mixture layer 22b. To cover the end of the mixture layer on the uncoated portion 23b side,
An insulating film 25a is provided.

In this battery 1, the insulating film 25 includes the uncoated portion 23 of the positive electrode mixture layer, the end portion of the one positive electrode mixture layer 22 on the side of the uncoated portion 23 of the positive electrode mixture layer, and the other positive electrode mixture. Since it is disposed so as to cover the end of the layer 22 on the uncoated portion 23 side of the positive electrode mixture layer, the uncoated portion 23 of the bent positive electrode mixture layer in the element 3 (hereinafter referred to as the bent portion). Even if a local load is applied to the positive electrode mixture layer 22, the positive electrode mixture layer 22 is prevented from peeling off or rubbing, in other words, powder falling is prevented. Therefore, the battery 1 is surely prevented from causing a short circuit due to powder falling, and has a good product yield and high quality.

On the main surface side of the positive electrode 20, the uncoated portion 23 of the positive electrode mixture layer and the uncoated portion 2 of the positive electrode mixture layer of one positive electrode mixture layer 22.
If the insulating film 25 is not disposed so as to cover the end on the side 3 and the end on the uncoated portion 23 side of the positive electrode mixture layer of the other positive electrode mixture layer 22, the cause of the short circuit at the bent portion. As a result, powder will fall off, resulting in a battery with a poor product yield.

Further, in this battery 1, it is appropriate that the bent portion formed by bending the positive electrode mixture uncoated portion 23 is folded within the range of the positive electrode mixture uncoated portion 23. The folding method of the bent portion is not particularly limited, for example, as shown in FIG.
As shown in, it is preferable that the positive electrode mixture is not folded and folded in a range.

The bent portion is composed only of the positive electrode current collector 21 and the insulating film 25, and is composed of the thickness of the bent portion and the positive electrode 20 and the negative electrode 10 which are laminated with the solid electrolyte film 2 interposed therebetween. There is a significant difference from the thickness of the electrode structure. Therefore, for example, when the element 3 is vacuum-sealed with the exterior film 4, a local stress is generated in the bent portion, and as a result, the solid electrolyte film 2 may be broken in the bent portion.

Therefore, in this battery 1, the bending portion is folded as described above, the difference between the thickness of the bending portion and the thickness of the electrode structure is corrected, and the stress is locally concentrated on the bending portion. Is being prevented. Therefore, in this battery 1, even when the element 3 is vacuum-sealed with the exterior film 4, the solid electrolyte film 2 sandwiched between the positive electrode 20 and the negative electrode 10 is not broken at the bent portion.

Further, in this battery 1, as shown in FIG. 6, a negative electrode lead 14a (first lead) is provided at one end of the negative electrode 10 so as to extend to the outside of the exterior film 4. As shown in FIG. 4, at one end of the positive electrode 20,
The positive electrode lead 24 so as to extend to the outside of the exterior film 4.
(Second lead) is provided, and the insulating films 16 and 26 are provided on at least one main surface of the negative electrode lead 14a and / or the main surface of the positive electrode lead 24.

In particular, as shown in FIG.
The insulating film 1 is formed on both surfaces of the
It is preferable that 6, 26 are provided.

There is a thickness difference between the leads 14 and 24 and the element 3. In particular, since the element 3 has a multilayer electrode structure, the thickness of the leads 14 and 24 (A in FIG. 5).
And the thickness of the element 3 (B in FIG. 5) is very significant. In the battery 1 in which the difference in thickness between the leads 14 and 24 and the element 3 is not corrected, a step due to the difference in thickness occurs between the leads 14 and 24 and the element 3 having the multilayer electrode structure. During vacuum sealing, stress locally concentrates on the difference between the thickness of the leads 14 and 24 and the thickness of the element 3 (hereinafter referred to as a step). As a result, the solid electrolyte film 2 may be physically destroyed at the step, and the battery may become impractical.

Therefore, in this battery 1, the positive electrode lead 24
And / or by disposing the insulating films 16 and 26 on the negative electrode lead 14 as described above,
The difference in thickness between the element 4 and the element 3 is corrected to prevent the stress from locally concentrating on the step. As a result, this battery 1
Even when the element 3 is vacuum-sealed with the exterior film 4, the solid electrolyte film 2 is reliably prevented from being physically damaged, and the product yield is good.

In particular, when the positive electrode lead 24 and the negative electrode lead 14 are laminated, the insulating films 16 and 26 are added to the positive electrode lead 14 and the negative electrode lead 14, so that an insulating effect at the time of welding can be obtained.

As the insulating films 16, 25 and 26,
Polyolefin-based materials such as polyethylene and polypropylene can be used.

The thickness of the insulating films 16, 25 and 26 is
It is appropriately selected depending on the desired battery shape, the location of the battery, the specifications of the electrolyte, and the like.
It is better to set m. If the insulation film is extremely thin, the insulation will be destroyed during welding, causing a short circuit inside the battery. The width of the insulating film is 0.5 than the electrode width.
It is good that it is wider than mm.

In the negative electrode 10, aluminum or the like can be used as the negative electrode current collector 11. The thickness of the negative electrode current collector 11 is appropriately selected depending on the desired battery performance and shape, but is preferably about 1 μm to 100 μm.

The negative electrode mixture layer 12 contains a negative electrode active material. As the negative electrode active material, it is preferable to use a lithium metal, a lithium alloy, or a material that can be doped or dedoped with lithium or lithium ions. Materials that can be doped or dedoped with lithium or lithium ions include pyrolytic carbon, cokes (pitch coke, needle coke, petroleum coke, etc.), graphites, glassy carbons, organic polymer compound fired products (phenolic resin, Carbon materials obtained by firing a furan resin or the like at a suitable temperature to carbonize it, carbon fibers, activated carbon, and the like. Polymers such as polyacetylene and polypyrrole can also be used as the material capable of being doped or dedoped with lithium or lithium ions. Examples of lithium alloys include lithium-aluminum alloys.

The thickness of the negative electrode mixture layer 12 is appropriately selected depending on the desired battery performance and shape, but is 3 μm to
It is preferable that compression molding is performed by a pressing machine or the like so that the thickness is about 50 μm.

In the positive electrode 20, aluminum or the like can be used as the positive electrode current collector 21. The thickness of the positive electrode current collector 21 is appropriately selected depending on the desired battery performance and shape, but the thickness after pressing is preferably about 10 μm to 50 μm.

The positive electrode mixture layer 22 contains a positive electrode active material. Examples of the positive electrode active material include TiS ₂ and Mo.
Metal sulfides or oxides such as S ₂ , NbSe ₂ , V ₂ O ₅ can be used. In addition, Li _x MO ₂ (M in the formula
Represents one or more kinds of transition metals, and x varies depending on the charge / discharge state of the battery and is usually 0.05 or more and 1.10 or less. It is possible to use a lithium composite oxide mainly containing). As the transition metal M constituting the lithium composite oxide, Co, Ni, Mn and the like are preferable. Specific examples of such a lithium composite oxide include LiCo
_{O 2, LiNiO 2, LiNi y} Co 1-y O 2 ( wherein, is 0 <y <1.), May be mentioned LiMn ₂ O ₄ or the like. In particular, LiCoO ₂ is preferably used as the positive electrode active material.

The thickness of the positive electrode material mixture layer 22 is appropriately selected depending on the desired battery performance and shape, but it is compression molded by a pressing machine or the like so that the thickness after pressing is about 5 μm to 50 μm. It is preferable.

The solid electrolyte film 2 is, for example, as disclosed in JP-A-1.
1-185773, JP-A-8-222235, etc., solid electrolytes, siloxanes, lithium salts, and TMPT (trimethylol-propane trimethacryl).
ate) and the like. In particular, it is preferable to use a polyethylene oxide derivative or an ethylene oxide copolymer as the solid electrolyte.

As the exterior film 4, metal foil, aluminum laminate film, polyethylene terephthalate (P
ET) film or the like can be used.

The battery configured as described above is manufactured according to the following steps.

First, a step of forming the negative electrode 10 in which the negative electrode mixture layer 12 containing the negative electrode active material is formed on both surfaces of the negative electrode current collector 11 is performed.

In the step of forming the negative electrode 10, first, the negative electrode mixture containing the negative electrode active material and the binder is uniformly applied to both surfaces of the negative electrode current collector 11 and dried. Next, after compression-molding using a roll press machine or a vertical press machine, it is slit into a desired shape, for example, a rectangular shape.

Next, the positive electrode mixture layer 22 containing the positive electrode active material is provided on the main surface of the positive electrode current collector 21, and the positive electrode mixture uncoated portion 2 is formed.
The step of forming a plurality of positive electrodes 20 is performed through the step 3.

In the step of forming the positive electrode 20, first, both surfaces of the positive electrode current collector 21 are intermittently coated with a positive electrode mixture containing a positive electrode active material, a conductive agent and a binder, and dried. Next, after compression molding using a roll press machine or a vertical press machine, it is slit into a desired shape, for example, a strip shape. The length and width of the positive electrode current collector 11 in the longitudinal direction are appropriately changed depending on desired battery characteristics, but are, for example, a rectangular shape having a length of about 200 mm and a width of about 5 mm.

Next, on the main surface side of the positive electrode 20, the uncoated portion 23 of the positive electrode mixture layer, the end of the one positive electrode mixture layer 22 on the uncoated portion 23 side of the positive electrode mixture layer, and the other positive electrode mixture layer. So as to cover the end of the agent layer 22 on the uncoated portion 23 side of the positive electrode mixture layer,
The first insulating film disposing step of disposing the insulating film 25 is performed.

Further, the negative electrode lead 14 is provided at one end of the negative electrode 10 so as to extend to the outside of the exterior film 4, and the positive electrode 20 is provided at one end of the positive electrode 20 so as to extend to the outside of the exterior film 4. A second insulating film arranging step of arranging the leads 24 and arranging the insulating films 16 and 26 on at least one main surface of the negative electrode lead 14 and / or the main surface of the positive electrode lead 24 is performed.

As a method for disposing the insulating films 16, 25 and 26, any conventionally known method can be applied. For example, a hot air method, an impulse seal method,
A heat welding method such as a high frequency method and an ultrasonic sealing method, or an adhesive application method such as a hot melt method is applied.

Next, a solid electrolyte film disposing step of disposing the solid electrolyte film 2 on the main surface of the positive electrode 20 or both surfaces of the negative electrode 10 is performed.

In this step, the solid electrolyte film 2 is
It may be attached to either one of the positive electrode mixture layer 22 and the negative electrode mixture layer 12, and the attaching method is not particularly limited.

By the way, the positive electrode 20 and the negative electrode 10 (hereinafter,
It is called an electrode. ) And the solid electrolyte film 2 have an influence on the load characteristics of the battery 1 and, consequently, the battery capacity. Therefore, it is necessary that the electrodes and the solid electrolyte film 2 are closely attached to their contact surfaces so that air is not caught therein.

For example, it is preferable that the solid electrolyte film 2 and the electrode are adhered to each other by line contact while keeping a certain constant angle to bring them into close contact with each other while pushing out air.

The entrapment of air not only hinders the adhesion between the electrode and the solid electrolyte film 2, but also the entrapped air expands during vacuum pressure reduction in the exterior step described later, so that the solid electrolyte film 2 is prevented. May be destroyed. Therefore, by disposing the solid electrolyte membrane 2 using the above method, it is possible to reduce the soft short circuit after vacuum decompression.

Next, through the solid electrolyte film 2,
The negative electrode mixture layers 12 provided on both surfaces of the negative electrode 10 are connected to the positive electrode 2
0 is bent at the portion 23 not coated with the positive electrode mixture to form the positive electrode 2
The element forming step of forming the element 3 sandwiched between the one positive electrode mixture layer 22 and the other positive electrode mixture layer 22 provided on the 0 main surface is performed.

Specifically, the negative electrode material mixture layers 12a, 12b,
After sticking the solid electrolyte film 2 (not shown) on 12c and 12d, as shown in FIG. 7, the negative electrode mixture layer 12a and the positive electrode mixture layer 22a are stuck together.

Next, as shown in FIG. 8, the uncoated portion 23b
Is bent in a valley fold direction to bond the negative electrode mixture layer 12b and the positive electrode mixture layer 22b.

Next, as shown in FIG. 9, the uncoated portion 23c
Is bent in a mountain fold direction, and the surface of the positive electrode current collector 21 on the opposite side of the surface on which the positive electrode mixture layer 22b is formed and the surface on the opposite side of the surface on which the positive electrode mixture layer 22c is formed. Positive electrode current collector 21
And the surface of.

Next, as shown in FIG. 10, the positive electrode mixture layer 2
2c and the negative electrode mixture layer 12c are bonded together.

Next, as shown in FIG. 11, the uncoated portion 23
The negative electrode mixture layer 12d and the positive electrode mixture layer 22d are attached to each other by bending d in the valley folding direction.

Next, the step of covering the element 3 with the covering film 4 is performed. The exterior of the element 3 by the exterior film 4 is
It is performed under reduced pressure in a vacuum. In this way, the battery 1 is manufactured.

According to the method of manufacturing the battery 1 configured as described above, the insulating film 25 is formed on the uncoated portion 23 of the positive electrode mixture layer and the uncoated portion of the positive electrode mixture layer of one positive electrode mixture layer 22. 23
By arranging so as to cover the end portion on the side and the end portion on the uncoated portion 23 side of the positive electrode mixture layer of the other positive electrode mixture layer 22 when a local load is applied to the bent portion. This prevents the positive electrode mixture layer 22 from peeling off or rubbing, in other words, preventing powder from falling off. Therefore, according to the manufacturing method of the battery 1, it is possible to reliably prevent the occurrence of a short circuit due to powder falling, and it is possible to provide the battery 1 having a good product yield and high quality.

In particular, according to the method of manufacturing the battery 1 configured as described above, the bent portion formed by integrally bending the positive electrode mixture uncoated portion 23 with the insulating film 25 is For example, by folding in a zigzag area within the application portion, the difference between the thickness of the bent portion and the thickness of the electrode structure is corrected to prevent stress from locally concentrating on the bent portion.
Thereby, even when the element 3 is vacuum-sealed by the exterior film 4, the solid electrolyte film 2 sandwiched between the positive electrode 20 and the negative electrode 10 is prevented from being broken at the bent portion, and the product yield is improved. It is possible to provide a battery 1 having good quality and high quality.

Further, according to the method of manufacturing the battery 1 having the above-described structure, at least one main surface of the negative electrode lead 14 and / or the main surface of the positive electrode lead 24, in particular, the negative electrode lead 1
Insulating film 16 on both surfaces of 4 and the main surface of positive electrode lead 24,
By disposing 26, the leads 14 and 24 and the element 3
The difference in thickness is corrected by narrowing the step between and to prevent stress from locally concentrating on the step. Therefore, according to the method for manufacturing the battery 1, even when the element 3 is vacuum-sealed with the exterior film 4, it is possible to reliably prevent the solid electrolyte film 2 from being physically destroyed, and the product yield is good. A high quality battery 1 can be manufactured.

The battery 1 to which the present invention is applied is not limited to the battery including the negative electrode 10 shown in FIG. 6 and the positive electrode 20 shown in FIG. 4, and a positive electrode having a plurality of positive electrode mixture layers 22 formed thereon, Further, the battery may include a negative electrode including a plurality of negative electrode current collectors 11.

A battery 101 to which the present invention is applied is, for example, a positive electrode 120 shown in FIG. 12 and a negative electrode 110 shown in FIG.
It may be a battery provided with. Note that, in the positive electrode 120 shown in FIG. 12 and the negative electrode 110 shown in FIG. 13, the same members as those of the positive electrode 20 shown in FIG. 4 and the negative electrode 110 shown in FIG.

This battery 101, as shown in FIG.
It has the element 3 provided with the positive electrode 120, the negative electrode 110, and the solid electrolyte film 2. Further, in this battery 101, the element 3 is packaged with a packaging film 4.

As shown in FIG. 12, the positive electrode 120 is formed by applying a positive electrode mixture containing a positive electrode active material to one main surface of a plurality of positive electrode current collectors 21 formed in a substantially rectangular shape. The positive electrode mixture layer 22 and the uncoated portion 23 where the positive electrode mixture is not applied are formed at both ends in the longitudinal direction, and the one positive electrode current collector 21 is provided continuously with the uncoated portion 23. The positive electrode mixture is connected to another adjacent positive electrode current collector 21 on one end side in the longitudinal direction via a connection portion 23 ′ not coated with the positive electrode mixture. In addition, at one end of the positive electrode current collector 21,
A positive electrode lead 24 is provided.

Specifically, the positive electrode 120 is the uncoated portion 23a not coated with the positive electrode mixture at one end of the one positive electrode current collector 21α in the longitudinal direction, and the first positive electrode mixture adjacent to the uncoated portion 23a. Agent layer 22a, the first positive electrode mixture layer 22a adjacent to the side opposite to the uncoated portion 23a side, the uncoated portion 23b, and the uncoated portion 23b adjacent to the side opposite to the first positive electrode mixture layer 22a side. Second positive electrode mixture layer 22b, second positive electrode mixture layer 2
2b, an uncoated portion 23c adjacent to the uncoated portion 23b side, a connection portion 23 'provided continuously with the uncoated portion 23c and not coated with the positive electrode mixture, and another positive electrode current collector 21β.
In the uncoated portion 23d continuously provided with the connection portion 23 ', the third positive electrode mixture layer 22c adjacent to the uncoated portion 23d, and the uncoated portion 23d side of the third positive electrode mixture layer 22c. The uncoated portion 23e adjacent to the opposite side, the fourth positive electrode mixture layer 22d adjacent to the opposite side of the uncoated portion 23e from the third positive electrode mixture layer 22c side, and the fourth positive electrode mixture layer 22d not yet formed An uncoated portion 23f adjacent to the coating portion 23e side is provided.

Then, in this battery 101, the positive electrode 1
In FIG. 20, as shown in FIG. 15, on the main surface side of the positive electrode 120, an uncoated portion 23 of the positive electrode mixture layer, an end portion of the one positive electrode mixture layer 22 on the uncoated portion 23 side of the positive electrode mixture layer, and An insulating film 25 is arranged so as to cover the end of the other positive electrode mixture layer 22 on the side of the uncoated portion 23 of the positive electrode mixture layer.

Specifically, for example, the uncoated portion 23b of the positive electrode mixture layer, the end of the positive electrode mixture layer 22a on the side of the uncoated portion 23b of the positive electrode mixture layer, and the positive electrode of the other positive electrode mixture layer 22b. To cover the end of the mixture layer on the uncoated portion 23b side,
An insulating film 25a is provided.

As a result, the battery 101 has the positive electrode material mixture layer 22 even when a local load is applied to the bent portion.
Peeling off and rubbing, in other words, the occurrence of powder falling is prevented. Therefore, this battery 101
Is surely prevented from causing a short circuit due to powder falling.

Further, in this battery 101, it is appropriate that the bent portion formed by bending the positive electrode mixture uncoated portion 23 is folded within the range of the positive electrode mixture uncoated portion 23. The folding method of the bent portion is not particularly limited, but it is preferable that the bent portion is folded and folded in the range of the positive electrode mixture uncoated portion 23.

By bending the bent portion and correcting the difference between the thickness of the bent portion and the thickness of the electrode structure, stress is prevented from locally concentrating on the bent portion. Thereby, the element 3
Even when vacuum sealing is performed with the exterior film 4, the solid electrolyte film 2 sandwiched between the positive electrode 120 and the negative electrode 110 can be prevented from being broken at the bent portion.

As shown in FIG. 13, a negative electrode 110 used in combination with the positive electrode 120 shown in FIG. 12 is formed on a plurality of substantially rectangular negative electrode current collectors 11 and both surfaces of the negative electrode current collector 11. And a negative electrode mixture layer 12 containing a negative electrode active material. A negative electrode lead 14 is provided at one end of the negative electrode current collector 11.

Specifically, the negative electrode 110 includes a negative electrode mixture layer 12a formed on one surface of one negative electrode current collector 11α and a negative electrode mixture layer 12a formed on the other surface of one negative electrode current collector 11α. The agent layer 12b, the negative electrode mixture layer 12c formed on one surface of the other negative electrode current collector 11β, and the negative electrode mixture layer 12d formed on the other surface of the other negative electrode current collector 11β. In addition, the negative electrode 11
At 0, one negative electrode lead 14a and the other negative electrode lead 14b
And are integrated.

Further, in this battery, as shown in FIG. 16, at one end of the negative electrode 110, the negative electrode lead 14a (first lead) is provided so as to extend to the outside of the exterior film 4.
15, the positive electrode lead 24 (second lead) is provided at one end of the positive electrode 120 so as to extend to the outside of the exterior film 4, and the negative electrode lead 14a is provided.
The insulating films 16 and 26 are disposed on at least one main surface of the above and / or the main surface of the positive electrode lead 24.

In particular, as shown in FIG. 14, the negative electrode lead 1
The insulating film 1 on both surfaces of 4 and the main surface of the positive electrode lead 24.
It is preferable that 6, 26 are provided.

At least one main surface of the negative electrode lead 14 and / or
Alternatively, the insulating films 16 and 26 are formed on the main surface of the positive electrode lead 24, particularly on both surfaces of the negative electrode lead 14 and the main surface of the positive electrode lead 24.
By disposing, the step difference between the leads 14 and 24 and the element 3 is narrowed to correct the thickness difference and prevent the stress from locally concentrating on the step. Therefore, according to the method of manufacturing the battery 101, even when the element 3 is vacuum-sealed with the exterior film 4, the solid electrolyte film 2 can be reliably prevented from being physically destroyed.

In the element 3, as shown in FIG. 14, the negative electrode material mixture layers 12 provided on both surfaces of the negative electrode 110 with the solid electrolyte film 2 interposed therebetween have the positive electrode 120 bent at the uncoated portion 23. Is sandwiched between one positive electrode mixture layer 22 and the other positive electrode mixture layer 22 provided on the main surface of the positive electrode 120. That is, the battery 1 includes the positive electrode 120 and the negative electrode 11.
An electrode having a laminated structure in which 0 and 0 are laminated is provided.

Further, the positive electrode 120 configured as described above.
The battery 101 including the negative electrode 110 and the negative electrode 110 is manufactured, for example, as follows.

First, the negative electrode material mixture layers 12a, 12b, 12
After sticking the solid electrolyte film 2 (not shown) on c and 12d, as shown in FIG. 17, the negative electrode mixture layer 12a and the positive electrode mixture layer 22a are attached.

Next, as shown in FIG. 18, the uncoated portion 23
B is bent in a valley fold direction to bond the negative electrode mixture layer 12b and the positive electrode mixture layer 22b.

Next, as shown in FIG. 19, the connecting portion 23 '
Is folded in a valley so as to be balanced with the longitudinal direction of the positive electrode 120,
A surface of the positive electrode current collector 21 opposite to the surface on which the positive electrode mixture layer 22b is formed and a surface of the positive electrode current collector 21 on the opposite side to the surface on which the positive electrode mixture layer 22c is formed. to paste together.

Next, as shown in FIG. 20, the positive electrode mixture layer 2
2c and the negative electrode mixture layer 12c are bonded together.

Next, the uncoated portion 23e is bent in a valley fold direction, and the negative electrode mixture layer 12d and the positive electrode mixture layer 22d are bonded together to form the element 3.

Next, the step of covering the element 3 with the covering film 4 is performed. The packaging of the element 3 with the packaging film 4 is performed under reduced pressure in a vacuum. In this way, the battery 101 is manufactured.

The battery 101 having the above-mentioned structure has a multi-layered electrode capable of ensuring a large electrode area, but the manufacturing process is simple, and short circuit and breakage of the solid electrolyte film 2 are surely prevented. And high quality.

The present invention is not limited to the battery 1 or the battery 101, but is a combination of the negative electrode having the shape of the positive electrodes 20 and 120 described above and the positive electrode having the shape of the negative electrodes 10 and 110 described above. May be

The shape of the battery to which the present invention is applied is not limited, but in particular, a long shape such as a strap, specifically, width 5 mm, length 180 mm, thickness 2 mm to 3 mm.
It is better to have such a shape.

[0098]

As is apparent from the above description, according to the battery and the manufacturing method thereof according to the present invention, the manufacturing process and the battery structure can be improved while having the electrode of the multilayer structure capable of ensuring a wide electrode area. Since it is simple, the battery can be manufactured relatively easily. Further, since the insulating film is arranged at a position where stress is generated when a local load is applied to the battery, there is a problem that the solid electrolyte is broken or powder is dropped to cause a short circuit. It is prevented. Therefore, according to the battery and the manufacturing method thereof according to the present invention, it is possible to provide a high-quality battery with a good product yield by a simple manufacturing process.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a battery to which the present invention has been applied.

FIG. 2A is a schematic view and FIG. 2B is a sectional view of a negative electrode.

FIG. 3A is a schematic view and FIG. 3B is a sectional view of a positive electrode.

FIG. 4 is (a) a schematic view and (b) a cross-sectional view of a positive electrode provided with an insulating film.

FIG. 5 is a cross-sectional view of a battery element.

6A is a schematic view and FIG. 6B is a sectional view of a negative electrode provided with an insulating film. FIG.

FIG. 7 (a) in the process of producing a battery to which the present invention is applied
It is a schematic diagram and (b) sectional drawing.

FIG. 8 is a schematic diagram in the process of manufacturing a battery to which the present invention has been applied.

FIG. 9 is a schematic diagram in the process of producing a battery to which the present invention has been applied.

FIG. 10 is a schematic diagram in the process of producing a battery to which the present invention has been applied.

FIG. 11 is a schematic diagram in the process of producing a battery to which the present invention has been applied.

12A is a schematic view and FIG. 12B is a perspective view of a positive electrode.

13A is a schematic view and FIG. 13B is a cross-sectional view of a negative electrode.

FIG. 14 is a cross-sectional view of another battery to which the present invention has been applied.

FIG. 15 is a schematic view of a positive electrode provided with an insulating film.

16 (a) is a schematic view and FIG. 16 (b) is a cross-sectional view of a negative electrode provided with an insulating film.

FIG. 17 is a schematic diagram in the process of manufacturing another battery to which the present invention has been applied.

FIG. 18 is a schematic diagram in the process of manufacturing another battery to which the present invention has been applied.

FIG. 19 is a schematic diagram in the process of manufacturing another battery to which the present invention has been applied.

FIG. 20 is a schematic diagram in the process of producing another battery to which the present invention has been applied.

[Explanation of symbols]

1,101 battery, 10,110 negative electrode, 20,120
Positive electrode, 16, 25, 26 Insulation film

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Toshikazu Yasuda             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Hidetoshi Murase             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation (72) Inventor Koji Shitoku             6-735 Kita-Shinagawa, Shinagawa-ku, Tokyo Soni             -Inside the corporation F term (reference) 5H017 AA03 AS02 BB08 BB14 HH05                 5H022 AA09 BB11 CC09                 5H029 AJ14 AK03 AK05 AL06 AL07                       AL08 AL12 AL16 AM16 BJ04                       BJ12 CJ03 CJ22 CJ28 DJ02                       DJ05 DJ07 HJ12                 5H050 AA19 BA16 BA17 BA18 CA07                       CA08 CA09 CA11 CB07 CB08                       CB09 CB12 CB22 CB25 DA04                       DA20 FA02 FA04 GA22 GA27                       HA12

Claims (20)

[Claims] 1. A first sheet in which a mixture layer containing either a positive electrode active material or a negative electrode active material is provided on both surfaces of a first current collector, and a main body of a second current collector. On the surface, a mixture layer containing either the positive electrode active material or the negative electrode active material on the other side is provided with a plurality of second sheets provided via a mixture uncoated portion, and an electrolyte film. On the main surface side of the sheet, the mixture layer uncoated portion, the end portion of the one mixture layer on the mixture layer uncoated portion side, and the end of the other mixture layer on the mixture layer uncoated portion side. An insulating film is provided so as to cover the portion, and the mixture layer provided on both sides of the first sheet is a non-mixed portion of the second sheet through the electrolyte film. An element formed by being bent and sandwiched between one mixture layer and another mixture layer provided on the main surface of the second sheet, Cell characterized by being sheathed with instrumentation film. 2. The bent portion formed by bending the uncoated portion of the mixture with the insulating film is folded within the range of the uncoated portion of the mixture. The battery according to 1. 3. The battery according to claim 2, wherein the bent portion is formed in a zigzag shape within the area where the mixture is not applied. 4. A first lead is provided at one end of the first sheet so as to extend to the outside of the exterior film, and one end of the second sheet is provided at the outside of the exterior film. The second lead is provided so as to extend toward
2. The battery according to claim 1, wherein an insulating film is provided on at least one main surface of the lead and / or the main surface of the second lead. 5. The battery according to claim 4, wherein the insulating film is provided on both surfaces of the first lead and the main surface of the second lead. 6. A step of forming a first sheet for forming a mixture layer containing either a positive electrode active material or a negative electrode active material on both surfaces of the first current collector, and a second current collector. A second sheet forming step of forming a plurality of mixture layers containing the other of the positive electrode active material and the negative electrode active material on the main surface of the second sheet through a mixture non-application portion; On the main surface side, the mixture layer uncoated portion, the end portion on the mixture layer uncoated portion side of the one mixture layer and the end portion on the mixture layer uncoated portion side of the other mixture layer. An insulating film disposing step of disposing an insulating film so as to cover; an electrolyte film disposing step of disposing an electrolyte film on the main surface of the second sheet or both surfaces of the first sheet; Through the film, the mixture layer provided on both sides of the first sheet is coated with the mixture layer on the second sheet. An element forming step of forming an element that is sandwiched between one mixture layer and another mixture layer provided on the main surface of the second sheet by bending at a portion; A method for manufacturing a battery, comprising a step of packaging. 7. The element forming step is characterized in that a bent portion formed by integrally bending the mixture-uncoated portion with the insulating film is folded within the mixture-uncoated portion. A method for manufacturing a battery according to claim 6. 8. The folding part is folded in a zigzag manner within the range where the mixture is not applied, and is folded.
A method for manufacturing the battery described above. 9. In the step of disposing the insulating film, a first lead is provided at one end of the first sheet so as to extend to the outside of the exterior film, and one end of the second sheet is provided. Providing a second lead so as to extend to the outside of the exterior film, and further disposing an insulating film on at least one main surface of the first lead and / or the main surface of the second lead. The method of manufacturing a battery according to claim 6, wherein the battery is manufactured. 10. The both sides of the first lead and the second side.
10. The method for manufacturing a battery according to claim 9, wherein the insulating film is provided on the main surface of the lead. 11. A first sheet in which a mixture layer containing either a positive electrode active material or a negative electrode active material is provided on both surfaces of the first current collector, and a main body of the second current collector. On the surface, a mixture layer containing either the positive electrode active material or the negative electrode active material, the other, is provided with a plurality of second sheets provided via a mixture uncoated portion, and an electrolyte film. A first lead is provided at one end of the sheet so as to extend outside the exterior film, and a second lead is provided at one end of the second sheet so as to extend outside the exterior film. Of the first sheet, an insulating film is provided on at least one main surface of the first lead and / or the main surface of the second lead, and the insulating film of the first sheet is provided via the electrolyte film. The mixture layers provided on both sides are formed by bending the second sheet at the mixture-uncoated portion. Batteries in which the second one of the mixture layer provided on the main surface of the sheet and becomes sandwiched between the other mixture layer element, characterized in that it is sheathed with an exterior film. 12. The both sides of the first lead and the second lead.
The battery according to claim 11, wherein the insulating film is provided on a main surface of the lead of the battery. 13. The main surface side of the second sheet, the mixture layer uncoated portion, the end of the one mixture layer on the mixture layer uncoated portion side, and the other mixture layer described above. The battery according to claim 11, wherein an insulating film is provided so as to cover the end portion on the side where the mixture layer is not applied. 14. The bent portion formed by bending the uncoated portion of the mixture with the insulating film is folded within the range of the uncoated portion of the mixture. 1
The battery according to 1. 15. The battery according to claim 14, wherein the bent portion is formed into a zigzag shape and folded within the area where the mixture is not applied. 16. A step of forming a first sheet, wherein a mixture layer containing either a positive electrode active material or a negative electrode active material is formed on both surfaces of the first current collector, and a second current collector. A second sheet forming step of forming a plurality of mixture layers containing the other of the positive electrode active material and the negative electrode active material on the main surface of the first sheet through the mixture uncoated portion; A first lead is provided at one end so as to extend to the outside of the exterior film, and a second lead is provided at one end of the second sheet so as to extend to the outside of the exterior film, An insulating film disposing step of disposing an insulating film on at least one main surface of the first lead and / or a main surface of the second lead, and on the main surface of the second sheet or both surfaces of the first sheet. , An electrolyte film disposing step of disposing an electrolyte film, and through the electrolyte film, The mixture layer provided on both sides of the first sheet is bent by bending the second sheet at a portion not coated with the mixture to form one mixture layer provided on the main surface of the second sheet, and the like. 5. A method for manufacturing a battery, comprising: an element forming step of forming an element sandwiched with the mixture layer of, and a step of packaging the element with an exterior film. 17. The both sides of the first lead and the second side.
17. The method for manufacturing a battery according to claim 16, wherein the insulating film is provided on the main surface of the lead. 18. In the step of disposing the insulating film,
On the main surface side of the second sheet, the mixture layer uncoated portion, the end of the one mixture layer on the mixture layer uncoated portion side and the other mixture layer uncoated. The method of manufacturing a battery according to claim 16, further comprising: disposing an insulating film so as to cover the end portion on the side of the portion. 19. In the element formation step, a bent portion formed by integrally bending the mixture-uncoated portion with the insulating film is folded within the range of the mixture-uncoated portion. A method of manufacturing a battery according to claim 16. 20. The method for manufacturing a battery according to claim 19, wherein the bent portion is folded and folded in the range of the mixture uncoated portion.