JP2007323907A - Battery outer sheath material and nonaqueous electrolyte secondary battery using this - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery outer sheath material capable of doing without a metal foil, and with downsizing and weight saving aimed at. <P>SOLUTION: The battery element outer sheath material is provided with a shape memory polymer layer, and metal oxide related to elements such as silicon, aluminum, and titanium. The nonaqueous electrolyte secondary battery is provided with a battery element made by winding around a cathode and an anode through a separator, and the battery element outer sheath material, and is made by sealing the battery element outer sheath material along a periphery of the battery element, with electrode terminals of the cathode and the anode led outside. The battery outer sheath material surrounding the battery element outer sheath material is provided with the shape memory polymer layer, and the metal oxide related to the elements such as silicon, aluminum, and titanium. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a battery outer packaging material for packaging a battery, and more specifically, a battery outer packaging material capable of avoiding the use of metal foil, and a battery using the same, which has been reduced in size and weight. The present invention relates to a non-aqueous electrolyte secondary battery.

In recent years, a large number of portable electronic devices such as camera-integrated video tape recorders, mobile phones, and portable computers have appeared, and their size and weight have been reduced. With the reduction in size and weight of such electronic devices, battery packs used as portable power sources are also required to have high energy and be reduced in size and weight.
As a battery used for such a battery pack, there is a lithium ion secondary battery having a high capacity.

A lithium ion secondary battery includes a battery element having a positive electrode and a negative electrode that can be doped / undoped with lithium ions, and is controlled by a circuit board that is electrically connected to the battery element. When forming a pack, a lithium ion secondary battery is stored in a storage case together with a circuit board (see, for example, Patent Document 1).
JP 2001-93945 A

  Here, the storage case is made of plastic or the like, and is divided into, for example, an upper case and a lower case. The storage case connects the upper case and the lower case to form a single housing having a space for storing the lithium ion secondary battery and the circuit board.

When forming a battery pack using such a storage case, the storage case needs to have a certain thickness in order to protect the lithium ion secondary battery and circuit board stored therein from external impacts and the like. . For this reason, the battery pack as a whole is thick and heavy.
In addition, when the storage cases divided into the upper and lower parts are joined with the double-sided tape, the thickness of the battery pack is further increased by the thickness of the double-sided tape. Furthermore, when the divided storage cases are joined together by ultrasonic welding, a certain amount of thickness is required for the ultrasonic welding portion, which increases the size of the battery pack.
Thus, in the conventional battery pack, the thickness of the storage case is inevitably increased, the overall size is increased, the weight is increased, and the application is not suitable for a portable power source.

On the other hand, a battery pack that is reduced in size and weight by arranging a frame so as to surround the battery and the circuit board and wrapping the battery, the circuit board, and the frame together in a thin plate-shaped package. It has been proposed (see, for example, Patent Document 2).
Japanese Patent Application Laid-Open No. 2005-158452

However, even in the battery pack described in Patent Document 2, a thickness of typically about 100 to 200 μm is typically obtained in order to obtain the necessary hardness and formability because a metal plate is used for the package. Further, the adhesive and the adhesive tape require a thickness of about 50 to 100 μm, and further improvement is desired.
It is also conceivable to use metal oxide ceramics for the exterior of battery packs, but metal oxide ceramics are harder than the metal itself, but are brittle, so there is a problem with the processing technology for thinly adhering to the exterior. It was.

  The present invention has been made in view of such problems of the prior art, and the object of the present invention is to provide a battery exterior material that can eliminate the need for a metal foil, and non-water that is reduced in size and weight. The object is to provide an electrolyte secondary battery.

  As a result of intensive studies to achieve the above object, the present inventors have found that the above object can be achieved by using a predetermined metal oxide, and have completed the present invention.

That is, the battery exterior material of the present invention comprises a shape maintaining polymer layer,
A metal oxide of at least one element selected from the group consisting of silicon, aluminum, titanium, zirconium, zinc, calcium, manganese, magnesium, niobium, tin, chromium, tungsten, nickel, and iron. Features.

Moreover, the suitable form of the battery cladding | exterior_material of this invention is combining the said metal oxide with the structural resin of the said shape maintenance polymer layer, and following General formula (1)
(MO) n-ORm (1)
(M in the formula is at least one metal element selected from the group consisting of silicon, aluminum, titanium, zirconium, zinc, calcium, manganese, magnesium, niobium, tin, chromium, tungsten, nickel and iron, m, n Is an integer of 1 or more, R is the same or different from each other, and represents a C1-10 alkyl group, an allyl group, or a C6-24 aryl group. It is characterized by constituting a similar organometallic oxide.

Furthermore, the non-aqueous electrolyte secondary battery of the present invention includes a battery element formed by winding a positive electrode and a negative electrode through a separator, and a battery element exterior material for packaging the battery element, and the positive electrode and the negative electrode. In the non-aqueous electrolyte secondary battery formed by sealing the battery element exterior material along the periphery of the battery element while leaving the terminal outside,
A battery exterior material surrounding the battery element exterior material,
This battery exterior material has a shape maintaining polymer layer,
A metal oxide of at least one element selected from the group consisting of silicon, aluminum, titanium, zirconium, zinc, calcium, manganese, magnesium, niobium, tin, chromium, tungsten, nickel, and iron. Features.

  According to the present invention, since a predetermined metal oxide is used, it is possible to provide a battery exterior material that can eliminate the need for a metal foil, and a nonaqueous electrolyte secondary battery that is reduced in size and weight.

  Hereinafter, the battery exterior material of the present invention will be described in detail. In the present specification and claims, “%” for concentration, content, filling amount and the like represents a mass percentage unless otherwise specified.

  As described above, the battery exterior material of the present invention is a battery, typically a polymer-type nonaqueous electrolyte secondary battery, in which a battery element formed by winding a positive electrode and a negative electrode through a separator is a metal laminate film. The battery is packaged with a battery element packaging material such as, and has a shape maintaining polymer layer and a predetermined metal oxide.

  Here, as the metal oxide, silicon (Si), aluminum (Al), titanium (Ti), zirconium (Zr), zinc (Zn), calcium (Ca), manganese (Mn), magnesium (Mg), niobium (Nb), tin (Sn), chromium (Cr), tungsten (W), nickel (Ni), iron (Fe) oxide, or any mixture of these oxides.

In addition, as the shape maintaining polymer layer, it is sufficient if it has a function of maintaining the shape of the battery outer packaging material. However, a polymer having affinity, compatibility or reactivity with the metal oxide is used as a constituent resin. For example, a polymer layer (polymer film) containing acryl silicone polymer, melamine polymer, urethane polymer or nylon as a constituent resin can be suitably used.
In addition, as a shape maintenance polymer layer, the adhesiveness with the metal laminate film which is a battery element exterior material is favorable, and a thing excellent in dimensional stability and a moldability is preferable.

In the battery outer packaging material of the present invention, the metal oxide functions to improve the hardness of the outer packaging material and is disposed in contact with the shape maintaining polymer layer.
For example, the metal oxide may be mixed into the shape maintaining polymer layer, and in this case, it is preferable that the metal oxide is uniformly dispersed throughout the shape maintaining polymer layer.

The mixing amount of the metal oxide can be appropriately changed according to the polymer type of the shape maintaining polymer layer, etc., and typically about 5 to 90% with respect to the mass of the shape maintaining polymer layer. It is preferable to do.
If it is less than 5%, the hardness of the battery outer packaging material may not be sufficiently improved, and if it exceeds 90%, there may be a problem in formability during production.

Further, in this battery exterior material, it is desirable to have a structure in which the metal oxide and the constituent resin of the shape maintaining polymer layer are combined.In this case, the metal oxide is a constituent resin of the shape maintaining polymer layer. The following general formula (1)
(MO) n-ORm (1)
(M in the formula is at least one metal element selected from the group consisting of silicon, aluminum, titanium, zirconium, zinc, calcium, manganese, magnesium, niobium, tin, chromium, tungsten, nickel and iron, m, n Is an integer of 1 or more, R is the same or different from each other, and represents a C1-10 alkyl group, an allyl group, or a C6-24 aryl group. Constructs a similar organometallic oxide.

  Furthermore, since it is sufficient that the above-described metal oxide is in contact with the shape maintaining polymer layer, the metal oxide layer is formed of such a metal oxide, and the metal oxide layer is formed outside the shape maintaining polymer layer. You may coat | cover at least one of the surface (surface side of the battery or battery pack obtained) and an inner surface (surface side facing a battery element).

  As described above, the battery exterior material of the present invention has a shape maintaining polymer layer and a predetermined metal oxide as essential constituent requirements, but can contain various additives other than this, for example, An ultraviolet absorber, a light stabilizer, a curing agent, or any mixture thereof can be added to the shape maintaining polymer layer to coexist with the metal oxide.

The battery outer packaging material of the present invention has a small thickness, for example, the shape maintaining polymer layer has a thickness of 150 μm or less. When the thickness of the shape-maintaining polymer layer exceeds 150 μm, even a battery or battery pack manufactured using this exterior material may not be effective in terms of volume energy density.
Moreover, the battery exterior material of this invention is excellent also in hardness, for example, the surface Vickers hardness is 100 or more. If the Vickers hardness is less than 100, good results may not be obtained in quality assurance tests such as drop tests.

As described above, the battery outer packaging material of the present invention can realize a battery pack that is thinner and stronger than the conventional one, and can also be reduced in size and weight.
Moreover, by using any of an ultraviolet absorber, a light stabilizer, and a curing agent together with the metal oxide or the organic metal oxide as described above, by using any of an acrylic resin, a melamine resin, a urethane resin, or nylon, a metal Since it is thinner than the plate and can be processed with high productivity, not only the energy density of the obtained battery is improved, but also the formation of the battery pack is easy, and the yield is improved.

  Also in the nail penetration test, which is a compulsory short-circuit test for grasping the reliability of the battery, in the battery using the conventional aluminum laminate film, the short-circuited part is concentrated in the minimum part due to the entanglement of the film part. However, in the present invention, the hardness of the exterior material is increased and the wrapping property of the film is reduced, so that concentration of short-circuited portions can be avoided, and the battery can be used even in such an abnormality. The temperature rise is effectively suppressed.

  Next, the battery exterior material and non-aqueous electrolyte secondary battery of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an exploded perspective view showing a battery before being packed with a battery outer packaging material in an embodiment of the nonaqueous electrolyte battery of the present invention.
In this figure, this battery 20 is produced by covering a battery element 10 with a metal laminate film 17 which is an example of a battery element exterior material, and the battery element 10 is formed with a recess 17a ( It is accommodated in the void 17a) and its periphery is sealed. In the present embodiment, the void 17a has a rectangular plate-shaped space corresponding to the shape of the battery element 10 having a rectangular plate shape.

Next, the configuration of the battery element 10 will be described.
FIG. 2 is a perspective view showing the structure of the battery element 10 that is packaged and accommodated in the laminate film 17. In this figure, the battery element 10 is formed by sequentially laminating a strip-like positive electrode 11, a separator 13a, a strip-like negative electrode 12 arranged to face the positive electrode 11, and a separator 13b, and winding them in the longitudinal direction. The gel electrolyte 14 is applied to both surfaces of the positive electrode 11 and the negative electrode 12.

  From the battery element 10, a positive electrode terminal 15 a connected to the positive electrode 11 and a negative electrode terminal 15 b connected to the negative electrode 12 are derived (hereinafter referred to as an electrode terminal 15 when a specific terminal is not specified). 15a and negative electrode terminal 15b have sealants 16a and 16b (hereinafter referred to as specific sealants) which are resin pieces such as polypropylene (PPa) modified with maleic anhydride in order to improve adhesion to a laminate film 17 to be packaged later. Is designated as sealant 16 as appropriate).

Hereinafter, the constituent elements of the above-described battery (before packing with the battery outer packaging material) will be described in detail.
[Positive electrode]
In the positive electrode, a positive electrode active material layer containing a positive electrode active material is formed on both surfaces of a positive electrode current collector. The positive electrode current collector is made of a metal foil such as an aluminum (Al) foil.
The positive electrode active material layer includes, for example, a positive electrode active material, a conductive agent, and a binder. Here, the positive electrode active material, the conductive agent, the binder, and the solvent only have to be uniformly dispersed, and the mixing ratio is not limited.

As the positive electrode active material, a metal oxide, a metal sulfide, or a specific polymer can be used depending on the type of the target battery. For example, when constituting a lithium ion battery, the following formula (2) is mainly used.
Li _X MO ₂ (2)
(Wherein M represents at least one transition metal and X varies depending on the charge / discharge state of the battery, but is usually 0.05 to 1.10.) Things are used. Note that cobalt (Co), nickel (Ni), manganese (Mn), or the like is used as the transition metal (M) constituting the lithium composite oxide.

As such lithium composite oxide, _{specifically, LiCoO 2, LiNiO 2, LiMn} 2 O 4 and _{LiNi y Co 1 - y O 2} (0 <y <1) , and the like.
A solid solution in which a part of the transition metal element is substituted with another element can also be used. Examples thereof include LiNi _0.5 Co _0.5 O ₂ and LiNi _0.8 Co _0.2 O ₂ .
These lithium composite oxides can generate a high voltage and have an excellent energy density. Furthermore, _{TiS 2,} MoS 2, may be used NbSe no lithium metal sulfides such as ₂ and _V 2 _{O 5} or the oxide as a cathode active material. These positive electrode active materials may be used alone or in admixture of a plurality of types.

  As the conductive agent, for example, a carbon material such as carbon black or graphite is used. Furthermore, as the binder, for example, polyvinylidene fluoride, polytetrafluoroethylene, polyvinylidene fluoride, or the like is used. Moreover, as a solvent, N-methylpyrrolidone etc. are used, for example.

  The above-described positive electrode active material, binder and conductive agent are uniformly mixed to form a positive electrode mixture, and this positive electrode mixture is dispersed in a solvent to form a slurry. Next, the slurry is uniformly applied on the positive electrode current collector by a doctor blade method or the like, and then dried at a high temperature to evaporate the solvent and press to form a positive electrode active material layer.

  The positive electrode 11 has a positive electrode terminal 15a connected to one end of the positive electrode current collector by spot welding or ultrasonic welding. The positive electrode terminal 15a is preferably a metal foil or a mesh-like one, but there is no problem even if it is not a metal as long as it is electrochemically and chemically stable and can be energized. Examples of the material of the positive electrode terminal 15a include aluminum.

[Negative electrode]
In the negative electrode, a negative electrode active material layer containing a negative electrode active material is formed on both surfaces of a negative electrode current collector. The negative electrode current collector is composed of a metal foil such as a copper (Cu) foil, a nickel foil, or a stainless steel foil.

  The negative electrode active material layer includes, for example, a negative electrode active material, a conductive agent and a binder as necessary. In addition, about a negative electrode active material, a electrically conductive agent, a binder, and a solvent, the mixing ratio is not ask | required similarly to a positive electrode active material.

As the negative electrode active material, lithium metal, a lithium alloy, a carbon material that can be doped / undoped with lithium, or a composite material of a metal-based material and a carbon-based material is used.
Specific examples of carbon materials that can be doped / undoped with lithium include graphite, non-graphitizable carbon, and graphitizable carbon. More specifically, pyrolytic carbons, cokes (pitch coke, needle coke, petroleum coke), graphites, glassy carbons, organic polymer compound fired bodies (phenolic resin, furan resin, etc.) at an appropriate temperature. Carbon materials such as those obtained by firing and carbonization), carbon fibers, and activated carbon can be used.
Furthermore, as a material that can be doped / undoped with lithium, polymers such as polyacetylene and polypyrrole, and oxides such as SnO ₂ can be used.

  In addition, various types of metals can be used as materials capable of alloying lithium, but tin (Sn), cobalt (Co), indium (In), aluminum, silicon (Si), and alloys thereof can be used. Often used. When metal lithium is used, it is not always necessary to use powder as a coating film with a binder, and a rolled lithium metal foil may be pressure-bonded to a current collector.

  As the binder, for example, polyvinylidene fluoride, styrene butadiene rubber or the like is used. Moreover, as a solvent, N-methylpyrrolidone, methyl ethyl ketone, etc. are used, for example.

  The above-described negative electrode active material, binder, and conductive agent are uniformly mixed to form a negative electrode mixture, which is dispersed in a solvent to form a slurry. Subsequently, after apply | coating uniformly on a negative electrode collector with the method similar to a positive electrode, it is made to dry at high temperature, a solvent is scattered, and a negative electrode active material layer is formed by pressing.

  Similarly to the positive electrode 11, the negative electrode 12 has a negative electrode terminal 15b connected to one end of the current collector by spot welding or ultrasonic welding, and this negative electrode terminal 15b is electrochemically and chemically stable. If it can be energized, there is no problem even if it is not metal. Examples of the material of the negative electrode terminal 15b include copper and nickel.

The positive electrode terminal 15a and the negative electrode terminal 15b are led out from the same direction, for example, from one side (usually one of the short sides) when the battery element 10 has a rectangular plate shape as shown in FIG. Although it is preferable, no short circuit or the like occurs and there is no problem in battery performance.
Moreover, the connection location of the positive electrode terminals 15a and 15b is not limited to the above example as long as electrical contact is established and the location and method of attachment are not limited.

[Electrolyte]
As the electrolytic solution, an electrolyte salt and a non-aqueous solvent that are generally used in lithium ion batteries can be used.

  Specific examples of the non-aqueous solvent include ethylene carbonate, propylene carbonate, γ-butyrolactone, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, dipropyl carbonate and ethylpropyl carbonate, or hydrogen of these carbonic acid esters as halogen. Examples include substituted solvents. One of these solvents may be used alone, or a plurality of these solvents may be mixed and used in a predetermined composition.

Moreover, as lithium salt which is an example of electrolyte salt, it is possible to use the material used for normal battery electrolyte solution. Specifically, LiCl, LiBr, LiI, LiClO ₃ , LiClO ₄ , LiBF ₄ , LiPF ₆ , LiNO ₃ , LiN (CF ₃ SO ₂ ) 2, LiN (C ₂ F ₅ SO ₂ ) ₂ , LiAsF ₆ , LiCF ₃ SO ₃ , LiC (SO ₂ CF ₃ ) ₃ , LiAlCl _4, LiSiF _{6, and the} like can be mentioned, but LiPF ₆ and LiBF ₄ are desirable from the viewpoint of oxidation stability. These lithium salts may be used alone or in combination of two or more.
The concentration for dissolving the lithium salt is not a problem as long as it can be dissolved in the non-aqueous solvent, but the lithium ion concentration is in the range of 0.4 mol / kg to 2.0 mol / kg with respect to the non-aqueous solvent. It is preferable that

In the case of using a gel electrolyte, the above-described electrolytic solution is gelled with a matrix polymer.
The matrix polymer is not particularly limited as long as it is compatible with a non-aqueous electrolyte obtained by dissolving the electrolyte salt in the non-aqueous solvent and can be gelled. Examples of such a matrix polymer include a polymer containing polyvinylidene fluoride, polyethylene oxide, polypropylene oxide, polyacrylonitrile, and polymethacrylonitrile in repeating units. Such a polymer may be used individually by 1 type, and may mix and use 2 or more types.

Among them, particularly preferable as the matrix polymer is polyvinylidene fluoride or a copolymer in which hexafluoropropylene is introduced into polyvinylidene fluoride at a ratio of 7.5% or less.
Such polymers usually have a number average molecular weight in the range of 5.0 × 10 ^{5 to} 7.0 × 10 ⁵ (500,000 to 700,000) or a weight average molecular weight of 2.1 × 10 ^{5 to} 3. It is in the range of 1 × 10 ⁵ (210,000-310,000), and the intrinsic viscosity is in the range of 1.7-2.1 dl / g.

[Separator]
The separator is composed of a porous film made of a polyolefin-based material such as polypropylene (PP) or polyethylene (PE), or a porous film made of an inorganic material such as a ceramic non-woven fabric. It is good also as a structure which laminated | stacked the porous film. Among these, polyethylene and polypropylene porous films are the most effective.

  In general, the thickness of the separator is preferably 5 to 50 μm, more preferably 7 to 30 μm. If the separator is too thick, the amount of the active material filled decreases, the battery capacity decreases, and the ionic conductivity decreases and the current characteristics deteriorate. On the other hand, if the film is too thin, the mechanical strength of the film decreases.

[Production of battery]
The gel electrolyte solution prepared as described above is uniformly applied to the positive electrode 11 and the negative electrode 12 and impregnated in the positive electrode active material layer and the negative electrode active material layer, and then stored at room temperature or subjected to a drying process. A state electrolyte layer 14 is formed.
Next, using the positive electrode 11 and the negative electrode 12 on which the gel electrolyte layer 14 is formed, the positive electrode 11, the separator 13 a, the negative electrode 12, and the separator 13 b are stacked and wound in this order to obtain the battery element 10.
Next, the battery element 10 is housed in a recess (vacant space) 17a of the laminate film 17 and packaged to obtain a gel-like nonaqueous electrolyte secondary battery.

As the laminate film 17, a conventionally known metal laminate film such as an aluminum laminate film can be used.
As such an aluminum laminate film, a film suitable for drawing and suitable for forming the recess 17a for accommodating the battery element 10 is preferable.

  In general, an aluminum laminate film has a laminated structure in which an adhesive layer and a surface protective layer are disposed on both sides of an aluminum layer, and a polypropylene layer (PP as an adhesive layer) in order from the inside, that is, the surface side of the battery element 10. Layer), an aluminum layer as a metal layer, and a nylon layer or a polyethylene terephthalate layer (PET layer) as a surface protective layer.

In this embodiment, as shown in FIGS. 1 and 2, the battery element 10 is packaged with the laminate film 17 as described above, and the periphery of the battery element 10 is welded and sealed to form the battery 20.
In addition, as described above, after the battery element 10 is accommodated and sealed in the battery element exterior material, as shown in FIGS. 3A and 3B, the concave portion in which the battery element 10 is accommodated. The portions on both sides of 17a (hereinafter referred to as side sealing portions as appropriate) 17b are bent toward the direction of the recess 17a.

The bending angle θ is preferably in the range of 80 ° to 100 °.
If the angle is less than 80 °, the side walls 17b provided on both sides of the concave portion 17a are too open, and the width of the battery 20 is widened, making it difficult to reduce the size of the battery 20 and improve the battery capacity. The upper limit of 100 ° is a value defined by the shape of the recess 17a. When the flat battery element 10 is accommodated, the limit value of the bending angle is about 100 °. In addition, the width | variety of the heat welding in the side sealing part 17b becomes like this. Preferably it is 0.5-2.5 mm, More preferably, it is 1.5-2.5 mm.

  In order to reduce the size of the battery 20 and improve the battery capacity, the folded width D of the side portion 17b is preferably set to a dimension equal to or smaller than the height h of the recess 17a or the thickness of the battery element 10. In order to reduce the size of the nonaqueous electrolyte secondary battery 20 and improve the battery capacity, the number of turns is preferably set to one.

  In the present embodiment, the aluminum laminate film (battery element exterior material) 17 of the battery 20 obtained as described above is covered / enclosed with the above-described battery exterior material of the present invention. A water electrolyte secondary battery is obtained.

FIG. 4 is an explanatory plan view showing a process of manufacturing the nonaqueous electrolyte secondary battery of the present embodiment by packing the battery with a battery exterior material.
First, the battery 20 is bent along the broken line in the figure (FIGS. 4A and 4B), and further the aluminum laminate film 17 is covered with the battery outer packaging material 18 so that the nonaqueous electrolyte secondary battery of the present embodiment. 30 is obtained (FIG. 4C).
A cross-sectional view of the obtained nonaqueous electrolyte secondary battery 30 cut along the bottom portion is shown in FIG. 5A, and a cross-sectional view cut along the extending direction of the electrode terminals is shown in FIG. 5B.

  The method of covering / enclosing with the battery exterior material is not particularly limited, but the battery exterior material is sprayed with a liquid containing the battery exterior material and then dried, or the battery is encased in the liquid containing the battery exterior material. It can be performed by immersing 20 and then curing it with ultraviolet light or heat.

Although the non-aqueous electrolyte secondary battery 30 using the gel electrolyte has been described in the above-described embodiment, the present invention can also be applied to a laminated film exterior battery using an electrolytic solution. In this case, in the above-described embodiment, the step of applying the gel electrolyte to the positive electrode and the negative electrode surface is omitted, and the step of injecting the electrolytic solution in the middle of the laminate film welding step is provided.
More specifically, after welding and sealing three sides around the battery element 10 having a rectangular plate shape, an electrolytic solution is injected from the opening of the remaining one side, and then this one side is welded. And can be sealed. Thereby, the whole shape of a sealing part becomes a rectangular frame shape.

  In addition, if the non-aqueous electrolyte secondary battery of the present invention is used, a battery pack that is reduced in size and weight can be obtained. However, such a battery pack is, for example, a non-aqueous electrolyte as in the above-described embodiment. The secondary battery can be manufactured by arranging a protection circuit that electrically protects the battery and a wiring board that includes a connection terminal that is connected to the target device.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to these Examples.

(Examples 1-35, Comparative Examples 1-3)
Benzotriazole-based ultraviolet absorber (trade name: Biosorb 591 manufactured by Kyodo Yakuhin Co., Ltd. or product name: Tinuvin 900) manufactured as a UV absorber, and hindered amine-based light stabilizer (trade name manufactured by Sankyo Co., Ltd.) as a light stabilizer. Sanol LS292) is an isocyanate curing agent (trade name: Coronate HX (solid content concentration: 100%, NCO ratio: 21.3%) manufactured by Nippon Polyurethane Co., Ltd.) or a product name: Dismodule BL3175 manufactured by Sumitomo Bayer Urethane Co., Ltd. (Solid content concentration: 75%, NCO ratio: 11.1%, solvent: solvent naphtha) were used and blended as shown in Table 1 to obtain compositions for battery outer packaging materials of each example.

In the battery as shown in FIG. 1 described above, a battery having a battery element exterior material (laminate film 17) in which an adhesive is applied to the inner surface side of an aluminum vapor-deposited PET film is prepared. The composition for battery outer packaging material of each example obtained as described above was coated to obtain a nonaqueous electrolyte secondary battery of each example.
In addition, the said coating process sprayed the solution obtained by adding 30 weight part of diisobutyl ketone to 100 weight part of the composition for battery exterior materials of each case on the surface of a laminate film with an air spray, and it was 5 minutes at room temperature. It was allowed to stand and then cured in an oven at 80 ° C. to form a coating layer having the thickness shown in Table 1 on the surface of the exterior material.

[Performance evaluation]
(1) Measuring method of Vickers hardness The Vickers hardness of the nonaqueous electrolyte secondary battery surface of each example was measured by Shimadzu HMV-1 / 2. The obtained results are also shown in Table 1.
(2) 1m height 10 times drop test method 1m height test 10 times, the nonaqueous electrolyte secondary battery of each example is dropped 10 times in a random direction from 1m height, and the battery is visually deformed after the test. It was determined that NG was confirmed and NG was not deformed and OK. The obtained results are shown in Table 1.

  Examples 1 to 17 in which the surface of a battery element exterior material (laminate film 17) in which an adhesive was applied to the inner surface side of an aluminum vapor-deposited PET film was coated with a metal oxide such as silicon or aluminum as a composition for battery exterior materials. These non-aqueous electrolyte secondary batteries belong to the scope of the present invention, but Table 1 shows that they have excellent characteristics in the Vickers hardness test and drop test.

  Examples 18 to 35 were obtained by using a siloxane-like organometallic compound having a structure represented by the above formula (1) as a battery exterior material, and belong to the scope of the present invention. It can also be seen that it has excellent characteristics in the drop test.

  Although not shown in Table 1, a siloxane-like organometallic oxide containing zirconium, zinc, calcium, manganese, magnesium, niobium, tin, chromium, tungsten, nickel and iron other than silicon, aluminum and titanium. It was also confirmed that even when used as a battery exterior material, excellent characteristics were obtained in the Vickers hardness test and the drop test as described above.

As mentioned above, although this invention was demonstrated by some suitable embodiment and an Example, this invention is not limited to this embodiment or an Example, A various deformation | transformation is possible within the range which does not deviate from the summary of this invention. It is.
For example, the battery element exterior material of the present invention can be used not only for the battery and battery element shown in FIG. 1 and the like, but also for various gel-like or polymer type non-aqueous electrolyte secondary batteries.

In one embodiment of the nonaqueous electrolyte battery of the present invention, it is an exploded perspective view showing a battery before being packed with a battery exterior material. It is a perspective view which shows the structure of the battery element packaged and accommodated in a laminate film. It is an end view which shows the side wall vicinity of the battery shown in FIG. It is plane explanatory drawing which showed the process which packs a battery with a battery exterior material and produces the nonaqueous electrolyte secondary battery of this embodiment. It is sectional drawing of a nonaqueous electrolyte secondary battery.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Battery element, 11 ... Positive electrode, 12 ... Negative electrode, 13a, 13b ... Separator, 14 ... Gel electrolyte, 15a ... Positive electrode terminal, 15b ... Negative electrode terminal, 16a, 16b ... Sealant, 17 ... Laminate film, 17a ... Concave ( Empty space), 17b ... side sealing part, 18 ... battery exterior material, 20 ... battery, 30 ... non-aqueous electrolyte secondary battery, [theta] ... folding angle, D ... folding width, h ... recess height

Claims (10)

A shape maintaining polymer layer;
A metal oxide according to at least one element selected from the group consisting of silicon, aluminum, titanium, zirconium, zinc, calcium, manganese, magnesium, niobium, tin, chromium, tungsten, nickel, and iron;
A battery exterior material characterized by comprising:   2. The battery exterior material according to claim 1, wherein the shape maintaining polymer layer comprises an acrylic silicone polymer, a melamine polymer, a urethane polymer, or nylon as a constituent resin.   The battery exterior material according to claim 1 or 2, wherein the shape maintaining polymer layer contains at least one additive selected from the group consisting of an ultraviolet absorber, a light stabilizer, and a curing agent.   The battery exterior material according to claim 1, wherein the metal oxide is mixed in the shape maintaining polymer layer. The metal oxide is combined with the constituent resin of the shape maintaining polymer layer, and the following general formula (1)
(MO) n-ORm (1)
(M in the formula is at least one metal element selected from the group consisting of silicon, aluminum, titanium, zirconium, zinc, calcium, manganese, magnesium, niobium, tin, chromium, tungsten, nickel and iron, m, n Is an integer of 1 or more, R is the same or different from each other, and represents a C1-10 alkyl group, an allyl group, or a C6-24 aryl group. The battery exterior material according to claim 1, comprising a similar organometallic oxide.   The battery exterior material according to claim 1, wherein the metal oxide forms a layer, and the metal oxide layer is coated on an outer surface and / or an inner surface of the shape maintaining polymer layer.   The battery exterior material according to claim 1, wherein the shape maintaining polymer layer has a thickness of 150 μm or less.   The battery exterior material according to claim 1, wherein the surface has a Vickers hardness of 100 or more. A battery element formed by winding a positive electrode and a negative electrode through a separator, and a battery element outer packaging material for wrapping the battery element, with the electrode terminals of the positive electrode and the negative electrode being led out to the outside, In the non-aqueous electrolyte secondary battery formed by sealing the battery element exterior material along
A battery exterior material surrounding the battery element exterior material,
This battery exterior material has a shape maintaining polymer layer,
A metal oxide of at least one element selected from the group consisting of silicon, aluminum, titanium, zirconium, zinc, calcium, manganese, magnesium, niobium, tin, chromium, tungsten, nickel, and iron. Non-aqueous electrolyte secondary battery characterized.   The nonaqueous electrolyte secondary battery according to claim 9, wherein the battery element exterior material is made of an aluminum laminate film.

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