JP2013048042A - Battery package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery package capable of securing the steam barrier property of a thin battery, and excellent in flexibility.SOLUTION: The battery package comprises: a thin battery including a sheet-shaped electrode group, a nonaqueous electrolyte, and a first exterior package for air-tightly accommodating the electrode group and the nonaqueous electrolyte; and a second exterior package for air-tightly accommodating the thin battery. The electrode group comprises: a first electrode including a first collector sheet and a first active material layer attached to the surface thereof; a second electrode including a second collector sheet and a second active material layer attached to the surface thereof; and an electrolyte layer interposing between the first active material layer and the second active material layer, the electrolyte layer including the nonaqueous electrolyte. The tensile elasticity of the first exterior package is 10 to 100 MPa, and the steam permeability of the second exterior package is equal to or less than 0.001 g/mday in an environment at a temperature of 40°C and relative humidity of 90%.

Description

  The present invention relates to a battery package including a thin battery including a sheet-like electrode group, a nonaqueous electrolyte, and a first exterior body for hermetically storing them, and a second exterior body for hermetically housing the thin batteries. About the body.

  In recent years, thin batteries have been used as power sources for small electronic devices such as mobile phones, audio recording / playback devices, watches, video and still image cameras, liquid crystal displays, calculators, IC cards, temperature sensors, hearing aids, and pressure-sensitive buzzers. It is used.

  Thin batteries are also used in devices that operate in contact with a living body (biological adhesive apparatus). As such a device, an iontophoresis transdermal drug delivery device or the like has been developed that supplies a drug into the body through a living skin when a predetermined potential is applied. Also, a measurement circuit that measures biological information such as body temperature, blood pressure, and pulse, a monitoring unit that checks the measured biological information, and radio transmission that transmits radio signals related to the biological information to facilities such as hospitals and fire fighters A sheet-like biological information measurement and transmission device including a circuit has been developed. When biometric information indicating a change in the health of the user is obtained, the biometric information is automatically transmitted to a hospital or the like.

  With the further miniaturization of the above-described small electronic devices and devices, there is a demand for further thinning of thin batteries. In response to such a demand, a thin battery using a thin and flexible laminate film for an exterior body has been studied (Patent Document 1). The laminate film is composed of a metal foil and resin layers formed on both sides thereof. In such a thin battery, a sheet-like electrode group including a positive electrode, a negative electrode, and an electrolyte layer disposed between the positive electrode and the negative electrode is housed in an outer package made of a bag-like laminate film. In general, a pair of leads are connected to the electrode group, and a part of them is exposed to the outside as an external terminal from the sealing portion of the exterior body.

  It has also been proposed to use a thin battery package made of a resin base film and a flexible inorganic material layer instead of an outer package made of a laminate film (Patent Document 2). By using silicon nitride, aluminum nitride, or the like for the inorganic material layer, it is possible to provide a package having relatively high sealing performance at low cost.

JP 2000-258881 A JP-A-6-231739

  However, a thin battery using a conventional outer package or package should be applied to a small electronic device to which various external forces may be applied even though the thickness of the battery is reduced as much as possible. Considering it, the flexibility is not enough. For example, in the case of an electronic device having a reduced thickness, such as a biological sticking type device, a considerable portion of the volume of the electronic device is occupied by a thin battery. When such an electronic device is brought into contact with a living body, if the flexibility of the thin battery is insufficient, a good wearing feeling cannot be obtained, and the user of the electronic device is uncomfortable. Therefore, further improvement in the flexibility of the thin battery is required.

  In order to improve the flexibility of the thin battery, it is conceivable to reduce the thickness of the outer package to the limit. However, the exterior body needs to play a role of protecting the constituent elements of the battery from the outside air, and in particular, barrier properties against water vapor are required. If the thickness of the exterior body is made too small in order to obtain high flexibility, it becomes difficult to ensure the necessary water vapor barrier property.

In view of the above, the present invention provides a thin battery including a sheet-like electrode group, a non-aqueous electrolyte, and a first exterior body that hermetically houses the electrode group and the non-aqueous electrolyte, and the thin battery is hermetically sealed. A second exterior body to be housed, and the electrode group includes a first electrode including a first current collector sheet and a first active material layer attached to the surface, a second current collector sheet and a surface thereof. A second electrode including an attached second active material layer; and an electrolyte layer including the non-aqueous electrolyte interposed between the first active material layer and the second active material layer. The battery has a tensile elastic modulus of 10 to 100 MPa and a water vapor transmission rate of 0.002 g / m ² · day or less in an environment having a temperature of 40 ° C. and a relative humidity of 90%. It relates to a package.

  The battery packaging body of this invention comprises the electronic device driven by the electric power supply from the said thin battery in one situation. In this case, the second exterior body hermetically stores the electronic device together with the thin battery.

By setting the tensile modulus of the first exterior body to 10 to 100 MPa, the flexibility of the thin battery is improved and the feeling of wearing on the human body is greatly improved. By setting the water vapor transmission rate of the second exterior body to 0.001 g / m ² · day or less in an environment of a temperature of 40 ° C. and a relative humidity of 90%, a sufficient barrier property is secured. When using a thin battery, the second exterior body is opened, and the thin battery or electronic device is taken out and used.

  According to the present invention, a sufficient water vapor barrier property is ensured by the second exterior body, and therefore it is not necessary to impart a high level of water vapor barrier property to the first exterior body. Therefore, the tensile elastic modulus of the first exterior body can be reduced to 10 to 100 MPa, and as a result, the flexibility of the thin battery can be sufficiently increased.

It is sectional drawing of the laminate film which forms the 1st exterior body or 2nd exterior body which concerns on one Embodiment of this invention. It is a II-II line schematic sectional view of a thin battery (Drawing 3) concerning one embodiment of the present invention. It is a top view of the thin battery which concerns on one Embodiment of this invention. It is IV-IV line schematic sectional drawing of the battery package (FIG. 5) which concerns on one Embodiment of this invention. It is a top view of the battery packaging body which concerns on one Embodiment of this invention. It is a schematic sectional drawing of the thin battery which concerns on other embodiment of this invention. It is a perspective view which shows an example of the battery-electronic device conjugate | zygote which comprises a biological information measuring device. It is a perspective view which shows an example of the external appearance of the deformed joint body. It is a top view which shows notionally an example of an iontophoresis percutaneous administration apparatus. It is the XX schematic sectional drawing of the iontophoresis transdermal administration device (FIG. 9). It is sectional drawing corresponding to FIG. 10 of an example of the battery-electronics assembly which integrated the thin battery in the iontophoresis transdermal administration device. It is a top view of the battery package which concerns on other embodiment of this invention. It is a top view of the battery packaging body which concerns on other embodiment of this invention. It is a circuit diagram of the battery-electronic device assembly according to an embodiment of the present invention. It is an example of the circuit diagram of a 1st circuit in case a load is an iontophoresis transdermal administration device. It is a figure which shows an example of the procedure at the time of forcibly discharging an example of the battery-electronic device assembly which comprises a forced discharge operation switch. It is a top view which shows an example of the battery which comprises a forced discharge operation switch. It is a schematic sectional drawing which shows the operation | movement from the state (a) in which the 1st SW terminal and 2nd SW terminal of an example of the pushbutton type forced discharge operation switch separated were contacted.

A battery package of the present invention is a thin battery (hereinafter also simply referred to as a battery) including a sheet-like electrode group, a non-aqueous electrolyte, and a first exterior body that hermetically houses the electrode group and the non-aqueous electrolyte. And a second exterior body for hermetically storing the battery. Here, the electrode group includes a first electrode including a first current collector sheet and a first active material layer attached to the surface thereof, and a second current collector sheet and a second active material layer attached to the surface thereof. A second electrode; and an electrolyte layer including a nonaqueous electrolyte interposed between the first active material layer and the second active material layer. That is, the thin battery is a primary or secondary nonaqueous electrolyte battery. The tensile modulus of the first exterior body is 10 to 100 MPa, and the water vapor transmission rate of the second exterior body is 0.001 g / m ² · day or less in an environment of a temperature of 40 ° C. and a relative humidity of 90%.

  In a thin battery in which the thickness of the electrode group is reduced, the influence of the flexibility of the outer package on the improvement of the flexibility of the entire battery cannot be ignored. By setting the tensile elastic modulus of the first exterior body that hermetically houses the electrode group and the nonaqueous electrolyte (that is, the power generation element) to 10 to 100 MPa, the flexibility of the battery is improved and the feeling of wearing on the human body is greatly improved. . Moreover, the intensity | strength required as an exterior body can be maintained. In terms of flexibility, it is desirable that the tensile modulus of the first exterior body is as small as possible, for example, 90 MPa or less, more preferably 80 MPa or less, and even more preferably 50 MPa or more. However, in consideration of mechanical strength such as bending resistance, 10 MPa or more is desirable, 15 MPa or more is more preferable, and 20 MPa or more is more preferable. These upper and lower limits can be arbitrarily combined to set the range of the tensile modulus.

However, such a 1st exterior body has the tendency for the barrier property with respect to water vapor | steam to become lower than the conventional laminate film and package. In this regard, a sufficient barrier can be obtained by setting the water vapor transmission rate of the second exterior body for hermetically storing the thin battery in an environment of a temperature of 40 ° C. and a relative humidity of 90% to 0.001 g / m ² · day or less. Sex is secured.

A 2nd exterior body has a role which protects the battery during the period which is not used from external air. Therefore, the water vapor transmission rate of the second exterior body, the lower the desirable, for example, is preferably from 0.0005 g / m ² · day, more preferably not more than ^{0.0001g / m 2 · day, 0.00005g} / m 2 · day The following is more preferable, and naturally it may be 0 g / m ² · day.

  The battery package of the present invention can include an electronic device driven by power supply from a thin battery. The electronic device may be hermetically housed with the second exterior body together with the thin battery. In this case, it is preferable that the thin battery and the electronic device are integrated into a sheet. Examples of such an electronic device include a biological information measurement device and an iontophoresis transdermal administration device. Hereinafter, a sheet-like article in which a thin battery and an electronic device are integrated is also referred to as a battery-electronic device assembly or a battery device. The sheet-like battery-electronic device assembly or battery device itself is configured to have flexibility.

  When using a battery or a battery-electronic device assembly, the second exterior body is opened, and the battery or assembly is taken out and used. Since the use period of the battery or the battery-electronic device assembly is shorter than the period during which the battery package is distributed and stored, the first exterior body only needs to have an appropriate barrier property. Does not require sex. As a use period of a battery or a battery-electronic device assembly, for example, 50 hours or less or 200 hours or less is assumed.

Even during a relatively short period of use of the battery or battery-electronic device assembly, it is desirable to eliminate as much as possible the influence of outside air on the power generation element of the battery. From this viewpoint, the water vapor transmission rate of the first exterior body temperature 40 ° C., at a relative humidity of 90% for, is preferably, less 1g / m ² · day or less 2g / m ² · day it is further preferred, more preferably not more than 0.3g / m ² · day, the following are particularly preferred 0.1g / m ² · day, of course, may be 0g / m ² · day.

  A 1st exterior body is comprised with the highly flexible sheet-like material excellent in bending resistance. Although the structure of a 1st exterior body is not specifically limited, For example, a water vapor | steam barrier layer and the resin layer formed in the both surfaces are included. By using the first exterior body having the barrier layer, it is possible to effectively reduce the influence of outside air (the influence of water vapor on the power generation element of the battery) during the use period of the battery or battery-electronic device assembly. .

  The material of the second exterior body is not particularly limited. However, it is convenient for the user that the second exterior body is also made of a highly flexible sheet-like material having excellent bending resistance because it is easy to open and handle. Therefore, it is preferable to use a sheet-like material including a barrier layer and resin layers formed on both sides thereof, as in the first exterior body.

  The tensile elastic modulus of the second exterior body is not particularly limited, but preferably has a tensile elastic modulus of, for example, 300 MPa or more from the viewpoint of achieving both sufficient water vapor barrier properties and strength as the exterior body. However, as described above, from the viewpoint of ensuring ease of opening and handling, the pressure is preferably 2000 MPa or less, and more preferably 1000 MPa or less.

  In a preferred embodiment, the second exterior body has a tensile modulus of 5 to 200 times that of the first exterior body. In a preferred embodiment, the first exterior body has a water vapor transmission rate 5 to 10,000 times that of the second exterior body.

  The thickness of the thin battery is not particularly limited, but it is preferably 1 mm or less, more preferably 0.7 mm or less, considering flexibility and a feeling of wearing on the human body. The thickness of the sheet-like battery-electronic device assembly may be slightly thicker than that of the thin battery, but is preferably 1 mm or less from the same viewpoint. However, if the thicknesses of the thin battery and the battery-electronic device assembly are both about 5 mm or less, relatively good wearability may be obtained. In addition, since it is technically difficult to make these thickness less than 50 micrometers, the minimum of thickness is 50 micrometers.

  When the thin battery is a primary battery (or even a secondary battery), the battery or the battery-electronic device assembly is discarded after use. At that time, if power remains in the battery, it is inconvenient when an unexpected external short circuit occurs or the battery is damaged. Therefore, it is desirable to forcibly discharge the used battery. Such forced discharge can be achieved, for example, by providing a forced discharge operation switch on the battery or the battery-electronic device assembly. For example, the forced discharge operation switch is a switch that switches between a state in which the first electrode and the second electrode are externally short-circuited and a state in which the first electrode and the second electrode are not externally short-circuited. Good. In other words, any switch that converts the connection (electrical connection) between the first electrode and the second electrode from the open state to the closed state and externally shorts the first electrode and the second electrode may be used.

  The forced discharge operation switch includes, for example, a first SW terminal electrically connected to the first electrode and a second SW terminal electrically connected to the second electrode. The first electrode and the first SW terminal are electrically connected through the first path. The second electrode and the second SW terminal are electrically connected through the second path. An external short circuit is formed by electrically connecting the first SW terminal and the second SW terminal. A part of these paths and / or each terminal of the forced discharge operation switch may be provided in an electronic device integrated with the battery. The first path and the second path can be formed of various conductive materials.

The structure of the electrode group is not particularly limited, but an electrode suitable for forming a sheet is used.
In a preferred embodiment, the electrode group includes a first electrode including a first current collector sheet and a first active material layer attached to one surface thereof, a second current collector sheet and a second electrode attached to one surface thereof. A second electrode including an active material layer; and an electrolyte layer interposed between the first active material layer and the second active material layer. The other surface of the first current collector sheet and the other surface of the second current collector sheet are in contact with the inner surface of the first exterior body.

  Such an electrode group basically has a structure in which one first electrode and one second electrode are bonded together, that is, a three-layer structure including a positive electrode, an electrolyte layer, and a negative electrode (or a positive electrode). Current collector sheet, positive electrode active material layer, electrolyte layer, negative electrode active material layer, and negative electrode current collector sheet). However, the present invention does not exclude a thin battery including an electrode group including at least one positive electrode and at least one negative electrode between the positive electrode and the negative electrode at both ends.

  In another preferred embodiment, the electrode group is attached to the pair of first electrode, the second current collector sheet, and both surfaces thereof, including the first current collector sheet and the first active material layer attached to one surface thereof. A second electrode including the second active material layer, and an electrolyte layer interposed between the first active material layer and the second active material layer. And the other surface of a pair of 1st electrical power collector sheet | seat is in contact with the inner surface of an exterior body, respectively.

  Such an electrode group basically has a structure in which one second electrode is sandwiched between a pair of first electrodes, that is, a pair of first electrodes on the outermost layer, a second electrode on the inner layer, and a first electrode It has a five-layer structure composed of two electrolyte layers interposed between the electrode and the second electrode. However, the present invention does not exclude a thin battery including an electrode group having a structure exceeding five layers including at least one additional first electrode and at least one additional second electrode. Further, in some cases, it does not exclude a thin battery having an electrode group in which one first electrode and one second electrode are overlapped and wound into a flat shape.

  When the first active material layer or the second active material layer is a negative electrode active material layer, the negative electrode active material layer may be a mixture layer containing a negative electrode active material, a binder, and a conductive agent as necessary. A deposited film formed by such a vapor phase method or a metal sheet may be used. Examples of the negative electrode active material included in the mixture layer include carbon materials (for example, graphite), silicon alloys, and silicon oxides. Examples of the deposited film include a silicon alloy film and a silicon oxide film. As the metal sheet, a sheet-like lithium metal or lithium alloy can be used. The thickness of the negative electrode active material layer is preferably 1 to 200 μm, for example.

  In addition, when the negative electrode active material layer contains metallic lithium or a lithium alloy, the forced discharge switch is particularly preferably incorporated into a battery or a battery-electronic device assembly from the viewpoint of improving safety. From the viewpoint of increasing the adhesion with the negative electrode current collector sheet, the thickness of the sheet-like lithium metal or lithium alloy is preferably 10 to 100 μm. By setting the thickness to 100 μm or less, the negative electrode active material layer can maintain excellent flexibility, and peeling of the negative electrode active material layer from the negative electrode current collector sheet is highly suppressed when the battery is bent. By setting the thickness of the negative electrode active material layer to 10 μm or more, it becomes easy to obtain a battery having a high energy density. Here, the thickness of the negative electrode active material layer is a thickness in an undischarged state or a charged state.

  When the first current collector sheet or the second current collector sheet is a negative electrode current collector sheet, a metal film, a metal foil, or the like is used for the negative electrode current collector sheet. The negative electrode current collector sheet preferably does not form an alloy with the negative electrode active material and is excellent in electronic conductivity. Therefore, the negative electrode current collector sheet is preferably at least one foil selected from the group consisting of copper, nickel, titanium, alloys thereof, and stainless steel. The thickness of the negative electrode current collector sheet is preferably 5 to 30 μm, for example. By setting the thickness of the negative electrode current collector sheet to 5 μm or more, the negative electrode current collector sheet can maintain excellent strength. By setting the thickness of the negative electrode current collector sheet to 30 μm or less, it is possible to impart higher flexibility to the negative electrode current collector, and it is difficult for large stress to occur in the negative electrode current collector sheet when bent.

  When the first active material layer or the second active material layer is a positive electrode active material layer, the positive electrode active material layer may be a mixture layer containing a positive electrode active material, a binder, and a conductive agent as necessary. Alternatively, a deposited film formed by a vapor phase method such as vapor deposition may be used. The positive electrode active material is not particularly limited. For example, at least one selected from the group consisting of manganese dioxide, carbon fluoride (fluorinated graphite), lithium-containing composite oxide, metal sulfide, and organic sulfur compound is used. it can. The thickness of the positive electrode active material layer is preferably 1 to 300 μm, for example.

As the positive electrode active material of the primary battery, fluorinated graphite represented by (CF _w ) _m (wherein m is an integer of 1 or more and 0 <w ≦ 1) or manganese dioxide is suitable. Examples of the positive electrode active material of the secondary battery include lithium-containing composite oxides such as Li _xa CoO ₂ , Li _xa NiO ₂ , Li _xa MnO ₂ , Li _xa Co _y Ni _1-y O ₂ , and Li _xa Co _y M _{1. -y O z, Li xa Ni 1} -y M y O z, such as _{Li xb Mn 2 O 4, Li} xb Mn 2-y M y O 4 is suitable. Here, M is at least one element selected from the group consisting of Na, Mg, Sc, Y, Mn, Fe, Co, Ni, Cu, Zn, Al, Cr, Pb, Sb and B, and xa = 0 to 1.2, xb = 0 to 2, y = 0 to 0.9, and z = 2 to 2.3. xa and xb are values before the start of charging / discharging, and increase / decrease by charging / discharging.

  When the first current collector sheet or the second current collector sheet is a positive electrode current collector sheet, a metal material such as a metal film, a metal foil, or a non-woven fabric of metal fibers is used for the positive electrode current collector sheet. The positive electrode current collector sheet is preferably at least one foil selected from the group consisting of, for example, silver, nickel, palladium, gold, platinum, aluminum, alloys thereof, and stainless steel. The thickness of the positive electrode current collector sheet is preferably 1 to 30 μm, for example.

Next, with reference to FIG. 1, the sheet-like material (laminate film) provided with the barrier layer and the resin layer formed on both surfaces thereof, which can be applied to the first exterior body and the second exterior body, will be described in detail.
The laminate film 8 includes an inorganic material layer (barrier layer) 8a, a first resin film 8b bonded to one surface of the barrier layer 8a, and a second resin film bonded to the other surface of the barrier layer 8a. 8c.

The inorganic material used for forming the barrier layer 8a is not particularly limited, but it is preferable to use a metal layer, a ceramic layer, or the like in terms of barrier performance, strength, bending resistance, and the like. Further, an inorganic material capable of forming a barrier layer having a withstand voltage of 3 volts or more on the basis of lithium (vs. Li ⁺ / Li) is preferable. Specifically, for example, metal materials such as aluminum, titanium, nickel, iron, platinum, gold, and silver, and inorganic oxide materials such as silicon oxide, magnesium oxide, and aluminum oxide are preferable. By forming a barrier layer having excellent withstand voltage, damage due to oxidation or the like of the barrier layer can be suppressed. Among these, aluminum, aluminum oxide, and silicon oxide are particularly preferable from the viewpoint of excellent balance between flexibility and barrier property of the obtained laminate film, and aluminum is particularly preferable from the viewpoint of low manufacturing cost.

  From the viewpoint of ensuring the flexibility of the first exterior body, the thickness of the barrier layer of the first exterior body is desirably as thin as possible, for example, preferably less than 35 μm, more preferably 1 μm or less, and more preferably 0.5 μm or less, More preferably, it is 0.1 μm or less. However, from the viewpoint of ensuring the barrier property during the use period of the thin battery or the battery-electronic device assembly, for example, 0.01 μm or more is preferable, 0.02 μm or more is more preferable, and 0.05 μm or more is more preferable. These upper limits and lower limits can be arbitrarily combined to set the thickness range. For example, in the first exterior body, a barrier layer having a thickness of 0.01 to 0.1 μm is preferable.

  On the other hand, the thickness of the barrier layer of the second exterior body needs to be superior to the barrier layer of the first exterior body. This is because the period during which the battery package is distributed and stored is relatively long. Therefore, the thickness of the barrier layer of the second exterior body is desirably relatively thick, for example, preferably 35 μm or more, more preferably 40 μm or more, and further preferably 45 μm or more. However, from the viewpoint of ensuring flexibility that is easy to handle for the user, the thickness of the barrier layer of the second exterior body is, for example, preferably 200 μm or less, more preferably 100 μm or less, and even more preferably 60 μm or less. These upper limits and lower limits can be arbitrarily combined to set the thickness range. For example, in the second exterior body, a barrier layer having a thickness of 35 to 100 μm is preferable.

  A laminate film suitable as a first exterior body having a barrier layer having a thickness of 0.01 to 1 μm is formed by forming a vapor deposition layer 8a of an inorganic material having a thickness of 0.01 to 1 μm on one surface of the first resin film 8b. Further, it is manufactured by laminating the second resin film 8c. The vapor deposition layer 8a is formed by depositing an inorganic material so that the average thickness is 0.01 to 1 μm. Specific examples of the vapor deposition method include vacuum vapor deposition, sputtering, ion plating, laser ablation, chemical vapor deposition, plasma chemical vapor deposition, and thermal spraying. Of these, the vacuum evaporation method is particularly preferably used.

  The average thickness of a vapor deposition layer becomes like this. Preferably it is 0.01-1 micrometer, More preferably, it is 0.02-0.3 micrometer. By setting the average thickness of the vapor deposition layer to 0.1 μm or less, the laminate film is particularly excellent in flexibility, and as a result, the flexibility of the battery is also increased. Moreover, the barrier property of the grade requested | required of the 1st exterior body can fully be ensured because the average thickness of a vapor deposition layer shall be 0.01 micrometer or more.

  A laminate film suitable as a second exterior body having a barrier layer having a thickness of 40 to 100 μm is, for example, a metal foil 8a having a thickness of 40 to 100 μm, and a first resin film 8b and a second resin film 8c. It is manufactured by sandwiching and laminating.

  From the viewpoints of ease of thermal welding, electrolyte resistance, and chemical resistance, the resin film material disposed on the inner surfaces of the first and second exterior bodies is polyethylene (PE), polypropylene (PP), or the like. Polyolefin, polyethylene terephthalate, polyamide, polyurethane, polyethylene-vinyl acetate copolymer (EVA) and the like are preferable. From the same viewpoint, the thickness of the resin film on the inner surface side is preferably 10 to 100 μm, more preferably 10 to 50 μm.

  From the viewpoint of strength, impact resistance and chemical resistance, the resin film disposed on the outer surface side of the first exterior body and the second exterior body is polyamide (PA) such as 6,6-nylon and 6-nylon, Polyester such as polyolefin, polyethylene terephthalate (PET), and polybutylene terephthalate is preferable. From the same viewpoint, the thickness of the resin film on the outer surface side is preferably 5 to 100 μm, more preferably 10 to 50 μm.

  Specifically, PP / Al foil / PA laminate film, PP / Al foil / PP laminate film, PE / Al foil / PE laminate film, acid-modified PP are used as the first and second exterior bodies. / PET / Al foil / PET laminate film, acid-modified PE / PA / Al foil / PET laminate film, ionomer resin / Ni foil / PE / PET laminate film, EVA / PE / Al foil / PET laminate film, A laminate film of ionomer resin / PET / Al foil / PET is exemplified.

  The total thickness of the laminate film is, for example, 15 to 300 μm, and preferably 30 to 150 μm. If the total thickness of the laminate film is within the above range, various performances required for the first exterior body and the second exterior body can be sufficiently ensured, and the thickness of the thin battery or the battery package is kept small. It is also easy.

Next, a thin battery according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 2 is a schematic cross-sectional view of the thin battery 21. FIG. 3 is a top view of the battery 21. 2 corresponds to a cross-sectional view taken along the line II-II in FIG. The battery 21 includes an electrode group 13 and a first exterior body 8 that houses the electrode group 13. The electrode group 13 includes a negative electrode 11, a positive electrode 12, and an electrolyte layer 7 interposed between the negative electrode 11 and the positive electrode 12. The negative electrode 11 has a negative electrode current collector sheet 1 and a negative electrode active material layer 2 attached to one surface of the negative electrode current collector sheet 1. The positive electrode 12 has a positive electrode current collector sheet 4 and a positive electrode active material layer 5 attached to one surface of the positive electrode current collector sheet 4. The negative electrode 11 and the positive electrode 12 are disposed so that the positive electrode active material layer 5 and the negative electrode active material layer 2 face each other with the electrolyte layer 7 interposed therebetween. A negative electrode lead 3 is connected to the negative electrode current collector sheet 1, and a positive electrode lead 6 is connected to the positive electrode current collector sheet 4. Part of the negative electrode lead 3 and the positive electrode lead 6 is exposed to the outside from the first exterior body 8, and the exposed portions function as a negative electrode external terminal and a positive electrode external terminal.

  The first exterior body 8 is formed of a laminate film having a barrier layer 8a and a first resin film 8b and a second resin film 8c respectively formed on both surfaces thereof as shown in FIG. Yes. The method for forming the laminate film on the first exterior body is not particularly limited. For example, when the laminate film has an area larger than the rectangular area when two electrode groups 13 are arranged along a plane, the laminate film is folded back at the center line, and the two opposing sides connected by the center line A bag-shaped first exterior body is obtained by adhering the peripheral portions of the two. On the other hand, if the laminate film is folded at the center line, and both ends of the laminate film are overlapped with each other, and then the ends are welded together, a cylindrical first exterior body is obtained.

  The negative electrode active material layer 2 is, for example, a sheet-like lithium metal or lithium alloy. As the lithium alloy, for example, a Li—Si alloy, a Li—Sn alloy, a Li—Al alloy, a Li—Ga alloy, a Li—Mg alloy, or a Li—In alloy is used. From the viewpoint of securing the negative electrode capacity, the proportion of elements other than Li in the lithium alloy is preferably 0.1 to 10% by weight. The negative electrode current collector sheet 1 is pressure-bonded with lithium metal or a lithium alloy, and the negative electrode current collector sheet 1 and the lithium metal or lithium alloy are brought into close contact with each other, whereby the negative electrode 11 is obtained.

  The positive electrode active material layer 5 is, for example, a mixture layer that is formed on one surface of the positive electrode current collector sheet 4 and includes a positive electrode active material, a binder, and, if necessary, a conductive agent. Since the mixture layer has good flexibility, it can sufficiently follow the deformation of the positive electrode current collector sheet when the battery is bent.

  Conductive agents included in the positive electrode or negative electrode mixture layer include graphites such as natural graphite and artificial graphite; carbon blacks such as acetylene black, ketjen black, channel black, furnace black, lamp black, and thermal black. Used.

  The binder to be included in the positive electrode or negative electrode mixture layer includes polyvinylidene fluoride (PVDF), fluorine resin such as polytetrafluoroethylene, acrylic resin such as polyacrylonitrile and polyacrylic acid, and rubber such as styrene butadiene rubber. And the like are used.

  As the electrolyte layer 7, for example, a polymer electrolyte, a solid electrolyte, a nonaqueous electrolytic solution impregnated in a separator, or the like can be used. Among these, a polymer electrolyte or a solid electrolyte is preferable from the viewpoint that leakage can be suppressed.

The polymer electrolyte is prepared, for example, by holding an electrolyte solution that is a mixture of a lithium salt and a non-aqueous solvent in a matrix polymer. Specific examples of the lithium salt include LiClO ₄ , LiBF ₄ , LiPF ₆ , LiCF ₃ SO ₃ , LiCF ₃ CO ₂ , and imide salts. Specific examples of the non-aqueous solvent include, for example, cyclic carbonates such as propylene carbonate, ethylene carbonate, and butylene carbonate; chain carbonates such as diethyl carbonate, ethyl methyl carbonate, and dimethyl carbonate; γ-butyrolactone, γ-valero And cyclic carboxylic acid esters such as lactones. Specific examples of the matrix polymer include, for example, polyvinylidene fluoride (PVdF), a copolymer containing vinylidene fluoride (VdF) and hexafluoropropylene (HFP) as repeating units, vinylidene fluoride (VdF) and trifluoroethylene. Fluoropolymers such as copolymers containing (TFE) as a repeating unit, silicon gel, acrylic gel, acrylonitrile gel, polyphosphazene modified polymer, polyethylene oxide, polypropylene oxide, and composite polymers, cross-linked polymers, modified polymers thereof, etc. Is mentioned.

  The solid electrolyte can be prepared, for example, by depositing a lithium ion conductor on the surface of the positive electrode or the negative electrode by using a PVD method or a CVD method. Specific examples of the lithium ion conductor include lithium sulfide.

  The nonaqueous electrolytic solution impregnated in the separator is prepared by mixing the lithium salt as described above and a nonaqueous solvent. As the separator, for example, a microporous film formed from a resin such as a polyolefin such as polyethylene or polypropylene or a polyamide such as polyamideimide is preferably used. The thickness of the separator is, for example, 8 to 30 μm.

  The negative electrode lead 3 and the positive electrode lead 6 are connected to the negative electrode current collector sheet or the positive electrode current collector sheet, for example, by welding. As the negative electrode lead, for example, a copper lead, a copper alloy lead, a nickel lead or the like is preferably used. As the positive electrode lead, for example, a nickel lead or an aluminum lead is preferably used.

A thin battery is produced as follows, for example.
The negative electrode and the positive electrode are arranged so that the negative electrode active material layer and the positive electrode active material layer face each other, and are overlapped via the electrolyte layer to constitute an electrode group. At this time, a negative electrode lead is attached to the negative electrode, and a positive electrode lead is attached to the positive electrode. On the other hand, after the electrode group is inserted from one opening of the first exterior body formed in a cylindrical shape, the opening is closed by thermal welding. At this time, the electrode group is arranged so that a part of the positive electrode lead and the negative electrode lead is exposed to the outside from one opening of the cylindrical first exterior body. This exposed portion becomes a positive external terminal and a negative external terminal. Next, after injecting a non-aqueous electrolyte from the other opening of the cylindrical first exterior body, the opening is closed by thermal welding. In this way, the electrode group is sealed in the first exterior body.

Next, a battery package according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 4 is a longitudinal sectional view of the battery package 31. FIG. 5 is a top view of the battery package 31. FIG. 5 corresponds to a cross-sectional view taken along line IV-IV in FIG. The battery 21 is hermetically stored by the second exterior body 9. The second exterior body 9 is formed by, for example, two opposing laminated films having the same shape. As shown in FIG. 1, the laminate film includes a barrier layer 8a, and a first resin film 8b and a second resin film 8c formed on both sides of the barrier layer 8a.

The battery package 31 is produced as follows, for example.
First, two laminated films having the same shape are stacked, and three peripheral edges of the opposing peripheral edges 9a are bonded by heat welding or the like. Thereby, the bag-shaped 2nd exterior body which consists of laminate films is obtained. Next, the thin battery 21 is inserted from the opening of the second exterior body corresponding to the peripheral portion of the remaining one side. Thereafter, the opening of the second exterior body is adhered and sealed by heat welding or the like. Before the opening is sealed, the inside of the second exterior body may be depressurized or an inert gas such as nitrogen may be sealed. By enclosing the inert gas inside the second exterior body, even if a pinhole or the like is generated in the second exterior body and the outside air enters the second exterior body, most of the inert gas is It takes a considerable amount of time to be replaced with outside air. Therefore, the influence of outside air on the battery 21 can be minimized.

Next, a first modification of the above embodiment will be described with reference to FIG. In this modification, the configuration of the thin battery is different from that of the above embodiment.
The battery 21A of FIG. 6 includes an electrode group 13A and a first exterior body 8A that houses the electrode group 13A. The electrode group 13A includes a single negative electrode 11A, a pair of positive electrodes 12A arranged so as to sandwich the negative electrode 11A, and an electrolyte layer 7A interposed between the negative electrode 11A and the positive electrode 12A. Such a structure has good symmetry, and even if it is bent in any direction, there is no great difference in the degree of stress applied to the battery 21A. Therefore, for example, it is convenient in that it is not necessary to be aware of the direction of the battery when the battery 21A is incorporated into an electronic device.

  The negative electrode 11A has a negative electrode active material layer 2A attached to both surfaces of the negative electrode current collector sheet 1A and the negative electrode current collector sheet 1A. On the other hand, the pair of positive electrodes 12A includes the positive electrode current collector sheet 4A and the positive electrode active material layer 5 attached only to one surface of the positive electrode current collector sheet 4A. The pair of positive electrodes 12A are arranged with the negative electrode 11A interposed therebetween so that the positive electrode active material layer 5A and the negative electrode 11A face each other with the electrolyte layer 7 interposed therebetween. A negative electrode lead 3A is connected to the negative electrode current collector sheet 1A, and a positive electrode lead 6A is connected to the positive electrode current collector sheet 4A. Part of the negative electrode lead 3A and the positive electrode lead 6A is exposed to the outside from the first exterior body 8A, and the exposed portions function as a negative electrode terminal and a positive electrode terminal. Note that a sealing material 10 may be interposed between the first exterior body 8A and each lead in order to improve the sealing performance. A thermoplastic resin can be used for the sealing material 10.

Next, a second modification of the above embodiment will be described with reference to FIGS. 7A, 7B, 7C, and 7D.
In recent years, in the medical field, a biopaste-type device has been developed for the purpose of a doctor or the like monitoring biometric information of a patient or the like. As such a bio-applied device, for example, a bio-information measuring device that is brought into contact with the skin of a living body and constantly measures and wirelessly transmits bio-information such as blood pressure, body temperature, and pulse. Similarly, development of an iontophoresis transdermal administration device that supplies a drug into the body through a living body skin when a predetermined electric potential is applied as a biological sticking type device is also in progress.

  The bio-applied device is also referred to as a wearable portable terminal, and is used in a state of being in close contact with a living body, and therefore is required to have a degree of flexibility that does not cause discomfort even if it is in close contact with the skin for a long time. Therefore, excellent flexibility is also required for the power source for driving the bio-applied device. Thin batteries are useful as power sources for such devices. Moreover, the living body sticking type | mold apparatus is convenient for the disposable type discarded after use. Therefore, the bioadhesive device is also suitable for use as a battery package that encloses a battery or a battery-electronic device assembly that is scheduled to be used within a predetermined period after opening.

  The battery package of this modification includes an electronic device that is driven by power supply from the battery together with the thin battery. As described above, biological information measuring devices and iontophoresis transdermal administration devices are suitable as electronic devices. The battery and the electronic device are integrated into a sheet and are hermetically stored in the second exterior body as a flexible battery-electronic device assembly (battery device).

FIG. 7 is a perspective view showing an example of a battery-electronic device assembly including a biological information measuring device. FIG. 8 shows an example of the appearance when the joined body is deformed.
The biological information measuring device 40 includes a sheet-like holding member 41 that holds the constituent elements. The holding member 41 is made of a flexible material, and the temperature sensor 43, the pressure sensitive element 45, the storage unit 46, the information transmission unit 47, the button switch SW1, and the control unit 48 are embedded in a region from the inside to the surface. It is. The thin battery 21 is accommodated in a flat space provided inside the holding member 41. That is, the battery 21 and the biological information measuring device 40 are integrated into a sheet, and constitute a battery-electronic device assembly 42. The battery 21 may have a structure as shown in FIGS. 2 to 3, a structure as shown in FIG. 6, or another structure.

  For example, an insulating resin material can be used for the holding member 41. By applying, for example, an adhesive 49 having adhesive strength to one main surface of the battery-electronic device assembly, the biological information measuring device 40 can be wound around the wrist, ankle, neck, or the like of the user.

  The temperature sensor 43 is configured using a thermal element such as a thermistor or a thermocouple, for example, and outputs a signal indicating the user's body temperature to the control unit 48. The pressure sensitive element 45 outputs a signal indicating the user's blood pressure and pulse to the control unit 48. For example, a nonvolatile memory can be used as the storage unit 46 that stores information corresponding to the output signal. The information transmission unit 47 converts necessary information into a radio wave according to a signal from the control unit 48 and radiates it. The switch SW1 is used when the biological information measuring device 40 is switched on and off. The temperature sensor 43, the pressure sensitive element 45, the storage unit 46, the information transmission unit 47, the switch SW1 and the control unit 48 are attached to, for example, a flexible substrate and are electrically connected by a wiring pattern formed on the substrate surface. .

  The control unit 48 includes a CPU (Central Processing Unit) that executes predetermined arithmetic processing, a ROM (Read Only Memory) that stores a control program for the device, and a RAM (Random Access Memory) that temporarily stores data. These peripheral circuits are provided, and the operation of each part of the biological information measuring device 40 is controlled by executing a control program stored in the ROM.

FIG. 9 is a top view conceptually showing an example of an iontophoresis transdermal administration device, and FIG. 10 is a schematic sectional view of the device. FIG. 10 corresponds to a cross-sectional view taken along line XX in FIG. FIG. 11 is a cross-sectional view corresponding to FIG. 10 of an example of a battery-electronic device assembly in which the thin battery 101 is integrated with the apparatus.
The iontophoresis transdermal administration device 40A includes a sheet-like holding member 111 that holds the constituent elements. The holding member 111 is made of a flexible material. Inside the holding member 111, there are a semiconductor element 112 for controlling the power from the thin battery, a pair of flat electrodes 113, 114, and a pair of reservoirs 113a, 114a facing the pair of electrodes 113, 114, respectively. Buried. The reservoirs 113a and 114a are both made of a gel material that can be energized. An ionic drug is sealed in either one of the reservoirs 113a and 114a. The semiconductor element 112 is an element having a rectifying action such as a constant current diode, and is connected in series with each electrode. The reservoirs 113a and 114a are directly attached to the skin of a living body such as a human body.

  When a voltage is applied between the pair of electrodes, the ionic drug placed between the electrodes is accelerated by the electric field between the electrodes and penetrates into the subcutaneous tissue. The penetrability of the drug from the skin is controlled by the semiconductor element 112.

Next, a third modification of the above embodiment will be described with reference to FIGS. In this modification, the number of thin batteries or battery-electronic device assemblies included in the second exterior body is arbitrarily set.
FIG. 12 is a top view showing a battery package 31A in which two thin batteries 21 are hermetically stored in one second exterior body 9A. FIG. 13 is a top view showing a battery package 31B in which two battery-electronic device assemblies 42A are hermetically stored in one second exterior body 9B. The battery-electronic device assembly 42A is, for example, an iontophoresis transdermal administration device 40A integrated with the thin battery 21. In any battery packaging body, the second exterior body is formed by stacking two laminated films and bonding the peripheral edges of the four sides of the opposing peripheral edges 9Aa and 9Ba by heat welding or the like. .

  The number of batteries or battery-electronic device assemblies included in the second exterior body is arbitrary, and more batteries or battery-electronic device assemblies may be hermetically stored in one second exterior body. In addition, the shape and size of the second exterior body, the arrangement of the adhesion portions, and the like are not particularly limited. For example, a laminate film having a predetermined size is folded in two to form a cylinder or bag, and then a battery or a battery-electronic device assembly is accommodated in the laminate film. It may be welded. Further, the portion of the laminate film between the adjacent batteries (9Ab in FIG. 12) or the portion between the battery-electronic device assembly (9Bb in FIG. 13) is thermally welded, and each battery or the battery-electronic device assembly. A sealed space may be provided every time.

  FIG. 13 shows a case where an electronic device (for example, iontophoresis transdermal administration device 40A) is arranged in parallel with the battery 21, but when the electronic device itself is formed into a sheet, the battery 21 and the electronic device It is good also as a laminated body which piles up an apparatus up and down.

Next, a fourth modification of the above embodiment will be described with reference to FIGS.
In this modification, the thin battery or the battery-electronic device assembly includes means for forcibly discharging the battery after use. When the battery or the battery-electronic device assembly is discarded after use, if power remains in the battery, it is desirable to forcibly discharge the battery before or within a short period after disposal. Therefore, it is desirable that the battery or the battery-electronic device assembly is provided with a forced discharge operation switch so that an external short circuit is formed in the battery by switching from the open state to the closed state after use.

  As shown in FIG. 14, the battery-electronic device assembly 100 normally includes a circuit (first circuit) 110 including a battery 101, an electronic device (load) 102, and respective paths connecting them in series. It has. The first circuit 110 is converted from the open state to the closed state by the first switch 103. When the load 102 is the biological information measuring device shown in FIGS. 7 and 8, the switch SW <b> 1 corresponds to the first switch 103.

  FIG. 15 is an example of a circuit diagram of the first circuit when the load 102 is an iontophoretic transdermal administration device. By switching the first switch 103 from the open state to the closed state, the battery 101, the constant current circuit 112 of the dosing device, and the pair of electrodes 113 and 114 of the dosing device are connected. A resistance R between the pair of electrodes 113 and 114 indicates a resistance between reservoirs made of a gel material affixed to the skin of a living body.

  In the case of this modification shown in FIG. 14, in addition to the first circuit 110, a second circuit 120 including a first electrode of the battery, a second electrode, a resistor 105, and respective paths connecting them in series. It comprises. The second circuit 120 is converted from an open state to a closed state by a forced discharge operation switch (second switch) 104. When the forced discharge operation switch 104 includes a first SW terminal connected to the first electrode via the first path and a second SW terminal connected to the second electrode via the second path, the first SW terminal An external short circuit is formed by connecting the second SW terminal.

  When the person who has finished using the battery-electronic device assembly converts the forced discharge operation switch from the open state to the closed state (connects the first SW terminal and the second SW terminal), the positive electrode and the negative electrode of the battery 101 become An external short circuit occurs only through the resistor 105. As a result, a relatively large current continues to flow through the second circuit 120, and the battery reaches a fully discharged state within a short period of time. The resistor 105 is connected in series with the battery 101 as necessary so that a large current does not flow through the second circuit. However, when there is no fear that a large current flows through the second circuit, for example, when a sufficient resistance already exists due to the contact state of the second switch or the path connecting the positive electrode and the negative electrode, the resistor 105 is further added. There is no need to connect.

  Since the battery and the battery-electronic device assembly are excellent in flexibility, they can be easily physically deformed. Therefore, the forced discharge operation switch 104 may be converted from an open state to a closed state by applying physical deformation to the battery or the battery-electronic device assembly. In this case, the first SW terminal and the second SW terminal that are separated from each other before the physical deformation is applied are in contact with each other in the state after the deformation.

Next, a specific configuration of the forced discharge operation switch (second switch) will be described.
The battery-electronic device assembly 42B of FIG. 16A has a rectangular shape, and is connected to the first electrode of the battery 21 via the first path near both ends of one side along the longitudinal direction. The first SW terminal 104x and the second SW terminal 104y connected to the second electrode of the battery 21 via the second path are provided. The battery-electronic device assembly 42B is, for example, an iontophoresis transdermal administration device 40A integrated with the thin battery 21. The first SW terminal 104x and the second SW terminal 104y are arranged to face each other when the battery-electronic device assembly 42B is bent at a predetermined bending position (broken line X). Since the battery-electronic device assembly 42B is a thin sheet, it can be easily folded by a person who has finished its use. That is, as shown in FIGS. 16B and 16C, the first SW terminal 104x and the second SW terminal 104y are brought into contact with each other by the operation of bending the battery-electronic device assembly 42B, and an external short circuit including the battery 21 is formed. It is formed.

  It is desirable that the folded battery-electronic device assembly 42B maintain the state where the first SW terminal 104x and the second SW terminal 104y are in contact with each other as shown in FIG. Therefore, it is preferable that the battery-electronic device assembly 42B includes fixing means that can fix the first SW terminal 104x and the second SW terminal 104y in contact with each other. In response to such a request, for example, it is desirable to apply an adhesive to the surface of the battery-electronic device assembly 42B on the side where the first SW terminal 104x and the second SW terminal 104y are exposed. Such an adhesive can also be used for attaching the battery-electronic device assembly 42B to a living body. Alternatively, one of the first SW terminal 104x and the second SW terminal 104y may be formed in a concave shape, and the other may be formed in a convex shape, and both may be engaged with each other.

  The form of the first SW terminal and the second SW terminal is not particularly limited. For example, the area of the first SW terminal and the second SW terminal may be increased in order to ensure reliable contact between the first SW terminal and the second SW terminal. In the case of an iontophoretic transdermal administration device, the reservoirs 113a and 113b may be the first SW terminal and the second SW terminal, respectively. Moreover, you may form not only a battery-electronic device assembly but the 1st SW terminal and 2nd SW terminal which comprise a forced discharge operation switch in battery itself.

  In the thin battery 21B shown in FIG. 17, the negative electrode lead 3A and the positive electrode lead 6A are led out from two opposite sides of a rectangular battery. The leads 3A and 6A have internal lead portions 3a and 6a covered with sealing materials 10A and 10B in addition to the portions exposed to the outside. The internal lead portions 3a and 6a are respectively connected to the first SW terminal 23 and the second SW terminal 24 exposed to the outside constituting the forced discharge operation switch. The areas of the first SW terminal 23 and the second SW terminal 24 are both 1 to 20% of the area surrounded by the outline of the battery. When the battery 21B is folded in half along the broken line Y, the first SW terminal 23 and the second SW terminal 24 are almost certainly in contact with each other. Further, the surface of the battery 21B where the first SW terminal 23 and the second SW terminal 24 are exposed is provided with an adhesive 25 over almost the entire surface except for the terminal surface. The state in which the second SW terminal 24 is in contact is maintained.

  The leads 3A and 6A are used as external terminals of the battery, and these are compatible with the internal lead portions 3a and 6a (first SW terminal 23 and second SW terminal 24). That is, the leads 3A and 6A are appropriately shaped and used as the SW terminals of the forced discharge operation switch, and the first SW terminal 23 and the second SW terminal 24 are used as external terminals of the battery (power supply terminals connected to electronic devices). May be used.

  When the forced discharge operation switch is converted from the open state to the closed state as the battery or the battery-electronic device assembly is folded, it is desirable that the battery or the battery-electronic device assembly is provided with a planned bending portion. The part to be bent is designed to be more flexible than the other part of the battery or battery-electronic device assembly. For example, the tensile modulus of the portion to be bent is designed to be smaller than the other portions. Or you may make the width | variety of a bending plan part narrower than another part.

  The forced discharge operation switch does not need to be converted from the open state to the closed state in accordance with the bending of the battery or the battery-electronic device assembly. For example, a push button type switch may be used. In addition, the forced discharge operation switch may not operate according to physical deformation of the battery or the battery-electronic device assembly. For example, when the battery-electronic device assembly is peeled off from the state of being attached to the living body, the end of use may be automatically detected, and the forced discharge operation switch may be controlled by the control circuit. Such a control circuit may be incorporated in an electronic device.

  FIG. 18 shows an example of a push button switch. In FIG. 18, the first SW terminal 23A has a cylindrical shape having an annular throttle portion (small diameter portion) 27, and the second SW terminal 24A disposed opposite to the first SW terminal 23A has a flat shape. As shown in FIG. 18 (a), at the peripheral edge of the second SW terminal 24A, the first SW terminal 23A and the second SW terminal 24A are separated from each other, and the flange portion 28 is engaged with the throttle portion 27 of the first SW terminal 23A. An insulative spacer 26 is attached. Before and during use of the battery or battery-electronic device assembly, the first SW terminal 23A and the second SW terminal 24A are separated (state (a)), and the first SW terminal 23A is connected to the second SW after the use. When pushed in toward the terminal 24A, as shown in FIG. 18B, the flange portion 28 engages with the throttle portion 27 and is fixed in a state where the first SW terminal 23A and the second SW terminal 24A are in contact with each other. The first SW terminal 23A is connected to, for example, a part of the lead piece 3b that is connected to the first electrode of the battery and led to the outside. Similarly, the second SW terminal 24A is connected to a part of the lead piece 6b that is connected to the second electrode of the battery and led out to the outside.

  Note that the means for forcibly discharging the battery is not limited to the second circuit as shown in FIG. When the sheeted electronic device has a pair of electrodes connected to the positive electrode and the negative electrode of the battery at symmetrical positions on the main flat surface as shown in FIGS. 9 and 10, the pair of electrodes It is good also as a structure which contacts by physical deformation, such as bending.

EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited to these Examples.
Example 1
The thin battery shown in FIGS. 2 and 3 was produced by the following procedure.
(1) Production of Negative Electrode As the negative electrode current collector sheet 1, an electrolytic copper foil having a thickness of 12 μm was prepared. A lithium metal foil (thickness: 20 μm) as the negative electrode active material layer 2 was pressure-bonded to one surface of the electrolytic copper foil with a linear pressure of 100 N / cm to obtain a negative electrode 11. After cutting this out to a size of 50 mm × 50 mm having a tab portion of 5 mm × 5 mm, a copper negative electrode lead 3 was ultrasonically welded to the tab portion.

(2) Production of positive electrode N-methyl-2-pyrrolidone containing electrolytic manganese dioxide heated at 350 ° C. as a positive electrode active material, acetylene black as a conductive agent, and polyvinylidene fluoride (PVDF) as a binder ( NMP) was mixed so that the weight ratio of manganese dioxide: acetylene black: PVDF was 100: 5: 5, and then an appropriate amount of NMP was added to obtain a positive electrode mixture paste.

  An aluminum foil (thickness: 15 μm) was prepared as the positive electrode current collector sheet 4. The positive electrode mixture is applied to one surface of the aluminum foil, dried at 85 ° C. for 10 minutes to form the positive electrode active material layer 5, and then compressed with a roll press at a linear pressure of 12000 N / cm. A positive electrode 12 was obtained. This was cut out to a size of 50 mm × 50 mm having a tab portion of 5 mm × 5 mm, and then dried under reduced pressure at 120 ° C. for 2 hours. An aluminum positive electrode lead 6 was ultrasonically welded to the tab portion.

(3) Preparation of electrode group After arranging the negative electrode 11 and the positive electrode 12 so that the negative electrode active material layer 2 and the positive electrode active material layer 5 face each other, a microporous polyethylene film ( The separator which consists of 52 mm x 52 mm and thickness 9 micrometers) was arrange | positioned, and the electrode group 13 was obtained.

(4) Battery assembly The electrode group 13 was accommodated in the 1st exterior body 8 which consists of a cylindrical laminated film which has an aluminum barrier layer. As the laminate film, a three-layer structure of PP layer (thickness 35 μm) / aluminum deposition film (thickness 0.05 μm) / nylon (PA) layer (thickness 15 μm) having a total thickness of about 50 μm was used. The PP layer was placed on the inside and the PA layer on the outside.

The positive electrode lead 6 and the negative electrode lead 3 were passed through one opening of the first outer package 8, and a part of the positive electrode lead 6 and a part of the negative electrode lead 3 were exposed from the outer package 8. One opening of the first exterior body 8 was closed by thermal welding with each lead interposed therebetween. The portions of the positive electrode lead 6 and the negative electrode lead 3 exposed from the inside of the first exterior body 8 to the outside were used as a positive electrode external terminal and a negative electrode external terminal, respectively. Next, 0.8 g of nonaqueous electrolyte was injected from the other opening of the first exterior body 8, and then degassed for 10 seconds under a reduced pressure environment of 660 mmHg. As the non-aqueous electrolyte, a non-aqueous solvent in which LiClO ₄ was dissolved at a concentration of 1 mol / L was used. As the non-aqueous solvent, a mixed solvent of propylene carbonate and dimethoxyethane (volume ratio of 1: 1) was used.

  The other opening of the first exterior body 8 was closed by heat welding, and the electrode group 13 was sealed in the first exterior body 8. Thus, a thin battery 21 (Battery A) having a size of 60 mm × 65 mm and a thickness of about 0.2 mm was produced. The obtained battery was aged at 45 ° C. for 1 day.

(5) Production of battery package The thin battery 21 was hermetically housed by the second exterior body 9 made of two laminated films having an aluminum barrier layer. First, two laminate films having a size of 65 mm × 65 mm were prepared. As the laminate film, a three-layer structure of PP layer (thickness 45 μm) / aluminum foil (thickness 40 μm) / nylon (PA) layer (thickness 25 μm) having a total thickness of about 120 μm was used. Two laminated films were overlapped so that the PP layer was on the inner side, and three peripheral edges of the opposing peripheral edges were bonded together by heat welding to form a bag-shaped second exterior body 9 made of the laminate film. Next, the battery 21 was inserted from the opening of the second exterior body corresponding to the peripheral portion of the remaining one side. Thereafter, the opening of the second exterior body was bonded by thermal welding in a nitrogen atmosphere, and a battery package A was obtained.

[Evaluation]

The tensile elastic modulus of each exterior body was measured by the following method.
The laminate film constituting each exterior body is cut into a tensile test No. 3 dumbbell with a parallel part width of 5 mm and a distance between marked lines of 20 mm, and a tensile test using a universal testing machine at a tensile speed of 5 mm / min in accordance with JIS K7161. The tensile modulus was obtained.

The water vapor transmission rate of each exterior body was measured by the following method.
Based on JIS K7129 B method, the water vapor transmission rate of the laminate film which comprises each exterior body was measured in the environment of temperature 40 degreeC, and relative humidity 90%.

  A thin battery and a battery package were produced in the same manner as described above except that the barrier layers of the first and second exterior bodies were changed as follows. “(Ratio)” is a comparative example.

  The smaller the tensile elastic modulus, the better the feeling of wearing on the human body. However, it can be seen from Table 1 that as the tensile modulus of the first exterior body decreases, the barrier layer becomes thinner and the water vapor transmission rate tends to increase. If the tensile modulus of the first exterior body exceeds 100 MPa, the flexibility of the battery becomes insufficient, and a sufficiently satisfactory mounting feeling cannot be obtained.

Next, each battery packaging body and a battery before being hermetically stored in the second exterior body are prepared, and stored in an environment having a temperature of 25 ° C. and a relative humidity of 60% for the following predetermined period. The discharge capacity of was measured. The discharge capacity of the battery before storage was similarly measured in advance. The capacity retention rate of the battery after storage before storage was calculated.
The discharge capacity was measured under the following conditions.
Environmental temperature: 25 ° C
Discharge current density: 250 μA / cm ² (current value per unit area of positive electrode)
End-of-discharge voltage: 1.8V
And the capacity | capacitance maintenance rate (%) of the battery after a preservation | save was calculated | required from the following formula.
Capacity maintenance rate (%) = (discharge capacity of battery after storage / discharge capacity of battery before storage) × 100

From the above, it can be seen that the performance of the thin battery is maintained for a long time regardless of the water vapor transmission rate of the first exterior body by hermetically storing it in the second exterior body having a low water vapor transmission rate.
In addition, after opening the second exterior body, even a battery having the first exterior body having a high water vapor transmission rate (low tensile elastic modulus) can be used in a short period required as a power source for driving electronic devices. If so, it can be seen that performance is maintained.

Example 2
A thin battery as shown in FIG. 17 was produced by the following procedure.
(1) Production of negative electrode Implementation was performed except that the size of the negative electrode 11 was a rectangle of 60 × 40 mm, the position of the tab portion and the negative electrode lead 3 was changed to the center of one short side, and the width of the negative electrode lead 3 was 6 mm. A negative electrode similar to Example 1 was produced.

(2) Production of positive electrode Implementation was performed except that the size of the positive electrode 12 was a rectangle of 60 × 40 mm, the position of the tab portion and the positive electrode lead 6 was changed to the center of one short side, and the width of the positive electrode lead 6 was 6 mm. A positive electrode similar to Example 1 was produced.

(3) Production of Electrode Group Similarly to Example 1, the negative electrode 11 and the positive electrode 12 were arranged so that the negative electrode active material layer 2 and the positive electrode active material layer 5 face each other. However, the positive electrode lead and the negative electrode lead were protruded in opposite directions. Thereafter, a separator made of a microporous polyethylene film (62 mm × 42 mm, thickness 9 μm) was disposed between the negative electrode 11 and the positive electrode 12 to obtain an electrode group 13.

(4) Battery Assembly The electrode group 13 was housed in the first exterior body 8 made of the same laminate film as used in Example 1. However, the size of the first exterior body 8 was changed according to the size of the electrode group 13. Further, the two laminated films are stacked so that the PP layer is on the inner side, and the peripheral edge portions corresponding to the pair of long sides are bonded by thermal welding among the opposing peripheral edge portions, and the first laminate made of a cylindrical laminate film. An exterior body was formed.

  The positive electrode lead 6 was passed through one opening of the first exterior body 8 and the negative electrode lead 3 was passed through the other opening, and a part of the positive electrode lead 6 and a part of the negative electrode lead 3 were exposed from the exterior body 8. One opening of the outer package 8 was closed by thermal welding with the negative electrode lead 3 interposed therebetween. Next, 0.8 g of nonaqueous electrolyte was injected from the other opening of the outer package 8 and then deaerated for 10 seconds under a reduced pressure environment of 660 mmHg. The same nonaqueous electrolyte as in Example 1 was used. Thereafter, the other opening of the first exterior body 8 was closed by heat welding with the positive electrode lead 6 interposed therebetween, and the electrode group 13 was sealed in the first exterior body 8. In this way, a thin battery 21 (battery X) having a size of 75 mm × 50 mm and a thickness of about 0.2 mm was produced. The obtained battery was aged at 45 ° C. for 1 day.

  A portion of the negative electrode lead 3 and the positive electrode lead 6 exposed from the inside of the outer package 8 to the outside was divided into two lead pieces along the protruding direction. Then, one negative electrode lead piece 3a and one positive electrode lead piece 6a were bent to the same surface side of the battery, covered with the insulating tape 10A except for the tip, and fixed to the battery. Next, copper foil and aluminum foil each having a size of 14 mm × 14 mm are welded to the tips of the negative electrode lead piece 3a and the positive electrode lead piece 6a as a negative electrode external terminal 23 and a positive electrode external terminal 24, respectively. 8 was pasted on the outer surface. An adhesive was applied to the margin of the surface of the first exterior body to which the copper foil and the aluminum foil were attached.

(5) Production of Battery-Electronic Device Assembly An iontophoresis transdermal administration device having a size of 80 mm × 70 mm as shown in FIGS. A semiconductor element 112 having a constant current diode is arranged at the center of one surface of the dosing device, and a pair of electrodes 113 and 114 and a pair of reservoirs 113a and 114a stacked thereon are arranged in parallel on the other surface. Arranged. A pair of connection terminals that are electrically connected to the electrodes 113 and 114 are disposed on both sides of the semiconductor element 112. The pair of connection terminals were brought into contact with the negative electrode external terminal 23 and the positive electrode external terminal 24 of the battery 101, respectively, and as shown in FIG. The battery and the dispensing device were fixed to each other by the adhesive applied to the battery.

  The other negative electrode lead piece 3A and the other positive electrode lead piece 6A were bent toward the dosing device side, covered with an insulating tape except for the tip, and fixed to the dosing device. Next, copper foil and aluminum foil each having a size of 14 mm × 14 mm were welded to the tips of the negative electrode lead piece 3A and the positive electrode lead piece 6A as a negative electrode SW terminal and a positive electrode SW terminal, respectively. The negative electrode SW terminal and the positive electrode SW terminal were attached to the peripheral portion of the surface where the reservoir of the dosing device was exposed with an adhesive, thereby completing the battery-electronic device assembly.

(6) Production of battery packaging body The battery-electronic device assembly was hermetically housed in the same manner as in Example 1 with the second exterior body 9 made of the same laminate film as used in Example 1. After 1000 hours, the second exterior body was opened, the battery voltage of the battery-electronic device assembly was measured, the dosing device was activated, and 10% of the battery capacity was consumed. Then, the battery-electronic device assembly was folded and fixed so that the negative electrode SW terminal and the positive electrode SW terminal provided on the surface where the reservoir of the dosing device was exposed were in contact with each other. When the battery voltage was measured after 24 hours, it was 0.05 V, and it was confirmed that the battery was in a completely discharged state.

  The battery package of the present invention is a thin battery that is required to ensure flexibility as well as a barrier property against water vapor, and an electronic device integrated therewith, in particular, an iontophoresis transcutaneous used by being attached to a living body. The present invention can be applied to small electronic devices such as a medication device and a biological information measurement device.

  1: negative electrode current collector sheet, 2: negative electrode active material layer, 3: negative electrode lead, 4: positive electrode current collector sheet, 5: positive electrode active material layer, 6: positive electrode lead, 7: electrolyte layer, 8: first exterior Body, 9: second exterior body, 11: negative electrode, 12: positive electrode, 13: electrode group, 21, 101: thin battery, 31: battery package, 40, 102: electronic device, 41: holding member, 42, 100 : Battery-electronic device assembly, 103: first switch, 104: forced discharge operation switch (second switch), 105: resistance, 110: first circuit, 120: second circuit

Claims (14)

A thin battery including a sheet-like electrode group, a non-aqueous electrolyte, and a first exterior body for hermetically housing the electrode group and the non-aqueous electrolyte, and a second exterior body for hermetically housing the thin battery, Including
The electrode group includes a first electrode including a first current collector sheet and a first active material layer attached to a surface thereof, and a second electrode including a second current collector sheet and a second active material layer attached to the surface thereof. An electrode, and an electrolyte layer including the non-aqueous electrolyte interposed between the first active material layer and the second active material layer,
The tensile modulus of the first exterior body is 10 to 100 MPa,
The battery packaging body has a water vapor transmission rate of 0.001 g / m ² · day or less in an environment of a temperature of 40 ° C. and a relative humidity of 90%. ^2. The battery package according to claim 1, wherein the water vapor permeability of the first outer package is 1 g / m ² · day or less in an environment of a temperature of 40 ° C. and a relative humidity of 90%.   3. The battery package according to claim 1, wherein the first exterior body includes a water vapor barrier layer and a resin layer formed on both surfaces of the barrier layer, and the thickness of the barrier layer is less than 35 μm.   The battery package according to claim 3, wherein the barrier layer has a thickness of 1 μm or less.   The said 2nd exterior body contains the water vapor | steam barrier layer and the resin layer formed in both surfaces of the said barrier layer, and the thickness of the said barrier layer is 35 micrometers or more, Any one of Claims 1-4. Battery packaging.   The battery packaging body according to any one of claims 1 to 5, wherein the barrier layer is a metal layer or a ceramic layer.   The battery packaging body according to any one of claims 1 to 6, wherein the thin battery has a thickness of 1 mm or less. Furthermore, it comprises an electronic device driven by power supply from the thin battery,
The battery package according to claim 1, wherein the second exterior body hermetically stores the electronic device together with the thin battery.   The battery package according to claim 8, wherein the thin battery and the electronic device are integrally formed into a sheet.   10. A forced discharge operation switch that switches between a state in which the first electrode and the second electrode are externally short-circuited and a state in which the first electrode and the second electrode are not externally short-circuited. The battery package according to any one of the above.   The battery package according to any one of claims 1 to 10, wherein the first active material layer or the second active material layer contains metallic lithium or a lithium alloy.   The battery package according to any one of claims 8 to 11, wherein the electronic device is a biological information measurement device or an iontophoresis transdermal administration device. The first active material layer is attached only to one surface of the first current collector sheet;
The second active material layer is attached only to one surface of the second current collector sheet;
The other surface of the first current collector sheet and the other surface of the second current collector sheet are in contact with the inner surface of the first exterior body, according to any one of claims 1 to 12. Battery packaging. A pair of the first electrodes;
The first active material layer is attached only to one surface of the first current collector sheet,
The second active material layer is attached to both surfaces of the second current collector sheet,
The second electrode is sandwiched between first active material layers of the pair of first electrodes,
The battery packaging body according to any one of claims 1 to 12, wherein the other surface of the first current collector sheet of the pair of first electrodes is in contact with the inner surface of the first exterior body.

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