JP4649294B2 - Nonaqueous electrolyte battery and portable information device - Google Patents

Description

  The present invention relates to a lithium ion non-aqueous electrolyte battery and a portable information device equipped with the same.

  As portable information devices such as mobile phones are becoming smaller, thinner, and higher in performance, the battery that is the power source is also becoming smaller and thinner. To date, lithium-ion secondary batteries with a thickness of 3 mm or less using laminate outer packaging have been put into practical use. However, lithium ion secondary batteries having deformability have not been put into practical use.

Here, a solar cell having a deformability using a molded member made of a shape memory alloy that surrounds a power generation element in a frame shape is known (see Patent Document 1).
JP 2004-253472 A

  However, as a result of examination by the inventors, it has been found that it is difficult to apply this configuration to a lithium ion secondary battery and to impart deformability.

  This is mainly due to the fact that lithium ion secondary batteries require higher sealing properties than solar cells. First, in the lithium ion secondary battery, the ingress of moisture promotes the deterioration of the power generation element. Next, in the lithium ion secondary battery, the negative electrode or the positive electrode expands and contracts during charging / discharging, resulting in a volume change. Then, since internal force arises with respect to a sealing part, sealing performance tends to deteriorate.

  In view of the above circumstances, an object of the present invention is to provide a nonaqueous electrolyte battery having deformability and high sealing performance, and a portable information device equipped with the nonaqueous electrolyte battery.

A non-aqueous electrolyte battery of the present invention includes a power generation element having a positive electrode, a negative electrode, and a non-aqueous electrolyte, and a laminate exterior material that houses the power generation element and has a pair of inner resin layers that are heat-sealed to each other at the periphery. And a rod-shaped shape memory resin sandwiched between inner resin layers, heat-sealed with the inner resin layer, and formed in the longitudinal direction of the peripheral portion.

  The portable information device according to the present invention includes the non-aqueous electrolyte battery and a central processing unit that drives the non-aqueous electrolyte battery as a power source.

  INDUSTRIAL APPLICABILITY The present invention can provide a nonaqueous electrolyte battery having deformability and high sealing performance and a configuration information device equipped with the nonaqueous electrolyte battery.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code | symbol shall be attached | subjected to a common structure through embodiment, and the overlapping description is abbreviate | omitted. Each figure is a schematic diagram for promoting explanation and understanding of the invention, and its shape, dimensions, ratio, and the like are different from those of an actual device. However, these are in consideration of the following explanation and known techniques. The design can be changed as appropriate.

(First embodiment)
The structure of an example of the nonaqueous electrolyte battery according to the first embodiment will be described with reference to FIGS. FIG. 1 is a schematic cross-sectional view of a flat nonaqueous electrolyte secondary battery according to the first embodiment. FIG. 2 is a schematic diagram of a side cross section indicated by a dotted line AA ′ in FIG.

  As shown in FIG. 1, the exterior material 1 houses an electrode group 8. The peripheral portion of the exterior material 1 made of a laminate film is sealed by heat sealing. A rod-shaped shape memory resin 2 is formed at substantially the center in the longitudinal direction of the peripheral edge portion sealed by the thermal fusion. The shape memory resin 2 is formed so as to surround the electrode group 8 in a frame shape. The positive electrode current collector and the negative electrode current collector of the electrode group 8, the positive electrode tab 9 and the negative electrode tab 10 that are electrically connected to each other, are extended to the outside of the exterior material.

  As shown in FIG. 2, the pair of exterior materials 1 sandwich the power generation element 8. The peripheral part of the exterior material 1 is sealed by heat-sealing. The packaging material 1 is composed of three layers: an outer resin layer 1a, a metal layer 1b, and an inner resin layer 1c. The shape memory resin 2 is surrounded by the inner resin layer 1c.

  The power generation element 8 has a laminated structure, and includes a positive electrode current collector 3, a positive electrode layer 4, a separator 5, a negative electrode layer 6, and a negative electrode current collector 7 in order from the top. The separator 5 protrudes from the positive electrode current collector 3 and the negative electrode current collector 7 on all four sides. A non-aqueous electrolyte (not shown) is held by the separator 5.

  The peripheral edge portion of the inner resin layer 1c is heat-sealed with a positive electrode tab 9 and a negative electrode tab 10 and a shape memory resin 2 (not shown) interposed therebetween. As a result, the power generation element 8 is sealed in a container formed of the exterior material 1.

  FIG. 3 is a schematic perspective view showing a state in which the nonaqueous electrolyte battery according to the first embodiment is deformed into an S shape. FIG. 4 is a schematic diagram of a side cross section indicated by a dotted line B-B ′ in FIG. 2.

  As shown in FIGS. 3 and 4, the nonaqueous electrolyte battery according to the first embodiment can be deformed into an S shape by heating to a predetermined temperature. This is because the frame-shaped shape memory resin 2 stores the S-shape.

  According to the first embodiment, since the internal resin layer and the shape memory resin have high adhesiveness, the sealing performance of the nonaqueous electrolyte battery can be improved.

  On the other hand, when a shape memory alloy is used instead of the shape memory resin, the adhesiveness between the shape memory alloy and the inner resin layer is poor, so that the sealing performance is poor.

  In addition, when a lithium ion secondary battery provided with a laminate exterior material is deformed, the power generation element cannot be held, and the parts constituting the power generation element such as the current collector, electrode layer, and separator are peeled off, and the internal impedance is remarkably increased. It will increase. However, according to the first embodiment, since the shape memory resin 2 surrounds the power generation element in a frame shape, the shape of the power generation element can be maintained and an increase in internal impedance can be suppressed.

  The frame-shaped shape memory resin 2 is not formed in the layer thickness direction of the power generation element 8 but is formed in the in-plane direction. For this reason, it contributes to thickness reduction of a nonaqueous electrolyte battery.

  Here, it is preferable to use a cross-linked polyolefin for the shape memory resin and a polyolefin for the inner resin layer in order to further improve the adhesion and to improve the electrolyte solution resistance. Furthermore, when cross-linked polypropylene is used for the shape memory resin, polypropylene is preferably used for the inner resin layer, and when cross-linked polyethylene is used for the shape memory resin, polyethylene is preferably used for the inner resin layer.

  Moreover, the cross-sectional shape of the shape memory resin 2 includes a rectangle, a flat shape, a circle, and the like. Among these, a circular shape is desirable for improving adhesion with the inner resin layer and improving bending strength. In the first embodiment, it is assumed that the shape memory resin 2 and the inner resin layer 1c are brought into close contact by thermal fusion. For this reason, the boundary between the shape memory resin 2 and the inner resin layer 1c may be unclear to some extent.

  In addition, the thickness of the shape memory resin 2 is preferably equal to or less than the thickness of the power generation element 8 in order to reduce the thickness of the nonaqueous electrolyte battery. Specifically, 0.3 mm or more and 2 mm or less are preferable.

  Moreover, it is preferable that the width | variety of the shape memory resin 2 is a width | variety of 20% or more and 50% or less with respect to the heat-sealed exterior material peripheral part. When it is 50% or less, the sealing property is improved, and when it is 20% or more, the shape retaining property is improved.

  In order to facilitate deformation, the nonaqueous electrolyte battery is preferably thin. Specifically, the thickness is 3 mm or less, more preferably 2 mm or less.

  In addition, although the example in which the electric power generation element 8 has a laminated structure was demonstrated in FIGS. 1-4, it is not restricted to this, For example, it can take a winding structure.

  Moreover, although the example which forms an airtight container using two exterior materials was demonstrated in FIGS. 1-4, it is not restricted to this, For example, one exterior material is folded in two and three sides are folded. It is also possible to constitute a sealed container by sealing by heat sealing.

  1 to 4 show an example in which the shape memory resin 2 is provided on all four sides and has a frame shape. However, the shape memory resin 2 is not limited to this, and the shape memory resin 2 is provided only in a portion to be deformed. Also good. For example, as shown in FIGS. 1 to 4, when deformed into an S shape, the shape memory resin may be provided on a pair of two sides facing each other. However, in order to maintain the shape of the power generation element 8, the shape memory resin 2 is preferably frame-shaped.

  Hereinafter, the positive electrode, the negative electrode, the separator, the nonaqueous electrolyte, the exterior material, and the shape memory resin constituting the power generation element will be described.

1) Positive electrode The positive electrode 4 has a structure in which a positive electrode layer containing an active material is supported on one surface or both surfaces of a positive electrode current collector.

1-1) Positive electrode layer The positive electrode layer contains a positive electrode active material and a binder.

  Examples of the positive electrode active material include oxides and polymers.

For example, as the oxide, manganese dioxide (MnO ₂ ) occluded Li, iron oxide, copper oxide, nickel oxide, and lithium manganese composite oxide (for example, Li _x Mn ₂ O ₄ or Li _x MnO ₂ ), lithium Nickel composite oxide (for example, Li _x NiO ₂ ), lithium cobalt composite oxide (Li _x CoO ₂ ), lithium nickel cobalt composite oxide (for example, LiNi _1-y Co _y O ₂ ), lithium manganese cobalt composite oxide (for example, LiMn _y Co _1-y O ₂ ), spinel-type lithium manganese nickel composite oxide (Li _x Mn _2-y Ni _y O ₄ ), lithium phosphorus oxide having an olipine structure (Li _x FePO ₄ , Li _x Fe _{1- y Mn y PO 4, Li x} CoPO 4 , etc.), iron sulfate (Fe ₂ (SO _{4) 3),} vanadium oxide (e.g. V ₂ O _5), and the like.

  For example, examples of the polymer include conductive polymer materials such as polyaniline and polypyrrole, and disulfide polymer materials. In addition, sulfur (S), carbon fluoride, etc. can be used.

Preferred positive electrode active materials include lithium manganese composite oxide (Li _x Mn ₂ O ₄ ), lithium nickel composite oxide (Li _x NiO ₂ ), lithium cobalt composite oxide (Li _x CoO ₂ ), lithium Nickel cobalt complex oxide (Li _x Ni _1-y Co _y O ₂ ), spinel type lithium manganese nickel complex oxide (Li _x Mn _2-y Ni _y O ₄ ), lithium manganese cobalt complex oxide (Li _x Mn _y Co _1-y O ₂ ), lithium nickel cobalt manganese composite oxide (Li _x Ni _1-yz Co _y Mn _Z O ₂ ), lithium iron phosphate (Li _x FePO ₄ ), and the like. (Note that x, y, and z are preferably in the range of 0 to 1.)
As the binder, for example, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVdF), ethylene-propylene-diene copolymer (EPDM), styrene-butadiene rubber (SBR), or the like can be used.

  The positive electrode layer may contain a conductive agent. Examples of the conductive agent include acetylene black, carbon black, and graphite.

  The blending ratio of the positive electrode active material, the conductive agent and the binder is preferably in the range of 80 to 95% by weight of the positive electrode active material, 3 to 20% by weight of the conductive agent, and 2 to 7% by weight of the binder.

  The thickness of the positive electrode layer is preferably in the range of 10 to 200 μm. Here, the thickness of the positive electrode layer means the distance between the surface of the positive electrode layer facing the separator and the surface of the positive electrode layer in contact with the current collector. By setting the thickness of the positive electrode layer within the range of 10 to 200 μm, the large current discharge characteristics and the cycle life can be improved. The thickness of the positive electrode layer is more preferably in the range of 30 to 100 μm. By setting it in this range, the large current discharge characteristics and the cycle life can be greatly improved.

  The positive electrode layer may contain an adhesive polymer. The polymer having adhesiveness is desirably one that can maintain high adhesiveness while holding the nonaqueous electrolyte. Furthermore, it is more preferable that such a polymer has high lithium ion conductivity. Specific examples include polyacrylonitrile (PAN), polyacrylate (PMMA), polyvinylidene fluoride (PVdF), polyvinyl chloride (PVC), and polyethylene oxide (PEO). As the polymer having adhesiveness, one or more selected from the above-mentioned types can be used. In particular, polyvinylidene fluoride is preferable. Polyvinylidene fluoride can retain a non-aqueous electrolyte, and if it contains a non-aqueous electrolyte, it partially gels, so that the ionic conductivity can be further improved.

  In addition, you may contain the polymer | macromolecule which has adhesiveness in the negative electrode layer and separator which are mentioned later. The total amount of the polymer having adhesiveness contained in the battery is preferably 0.1 to 6 mg per 100 mAh of battery capacity. A more preferable range of the total amount of the polymer having adhesiveness is 0.2 to 1 mg per 100 mAh of battery capacity.

1-2) Positive electrode current collector As the current collector, a porous conductive substrate or a nonporous conductive substrate can be used. These conductive substrates can be formed from, for example, aluminum, stainless steel, or nickel.

  Among these, it is preferable to use a conductive substrate having a two-dimensional porous structure in which holes having a diameter of 3 mm or less are present at a rate of 1 or more per 10 cm 2. That is, when the diameter of the hole opened in the conductive substrate is larger than 3 mm, there is a possibility that sufficient positive electrode strength cannot be obtained. On the other hand, when the proportion of holes having a diameter of 3 mm or less is smaller than the range, it is difficult to uniformly infiltrate the non-aqueous electrolyte into the electrode group, so that there is a possibility that a sufficient cycle life cannot be obtained. The diameter of the hole is more preferably in the range of 0.1 to 1 mm. Moreover, it is more preferable that the existence ratio of the holes is in the range of 10 to 20 per 10 cm 2.

  The conductive substrate having a two-dimensional porous structure in which holes having a diameter of 3 mm or less are present at a rate of 1 or more per 10 cm 2 is preferably in the range of 10 to 50 μm. If the thickness is less than 10 μm, sufficient positive electrode strength may not be obtained. On the other hand, when the thickness exceeds 50 μm, the battery weight and the thickness of the electrode group increase, and it may be difficult to sufficiently increase the weight energy density and volume energy density of the thin secondary battery. A more preferable range of the thickness is 10 to 30 μm.

  Moreover, you may obtain a positive electrode electrical power collector by forming into a film on the inner side resin layer of an exterior material, for example. The film forming means is not particularly limited. For example, metal powder coating (for example, screen printing), vapor deposition, sputtering, or the like can be employed.

  The thickness of the current collector is preferably in the range of 5 to 20 μm. This is because within this range, the balance between the positive electrode strength and the weight reduction can be achieved.

2) Negative electrode The negative electrode has a structure in which the negative electrode layer is supported on one surface or both surfaces of the negative electrode current collector.

2-1) Negative electrode layer The negative electrode active material is not particularly limited as long as it is a material that occludes and releases lithium. For example, carbonaceous materials, alloys, oxides, nitrides, sulfides that are known active materials Products, carbides, etc. can be listed. Further, from the viewpoint of reliability during overdischarge, a negative electrode active material in which the negative electrode operating potential is nobler than 1 V with respect to the lithium metal potential is preferable, and examples thereof include lithium titanate and iron sulfide.

  Examples of carbonaceous materials include graphite materials such as graphite, coke, carbon fiber, and spherical carbon, or carbonaceous materials, thermosetting resins, isotropic pitches, mesophase pitches, mesophase pitch-based carbon fibers, mesophase microspheres, etc. A mesophase pitch-based carbon fiber is preferable because the capacity and charge / discharge cycle characteristics are increased), and a graphite material or a carbonaceous material obtained by heat treatment at 500 to 3000 ° C. can be used. Among them, it is preferable to use a graphitic material having graphite crystals obtained by setting the temperature of the heat treatment to 2000 ° C. or more and having a (002) plane spacing d002 of 0.34 nm or less. A nonaqueous electrolyte secondary battery including a negative electrode containing such a graphite material as a carbonaceous material can greatly improve battery capacity and large current discharge characteristics. The inter-surface distance d002 is more preferably 0.336 nm or less.

  Examples of the alloy include lithium alloys such as a lithium aluminum alloy, a lithium tin alloy, a lithium lead alloy, and a lithium silicon alloy.

  Examples of the oxide include metal oxides such as tin oxide, silicon oxide, lithium titanium oxide, niobium oxide, and tungsten oxide.

  Examples of the nitride include metal nitrides such as lithium cobalt nitride, lithium iron nitride, and lithium manganese nitride.

  Examples of the sulfide include metal sulfides such as tin sulfide and titanium sulfide.

  The negative electrode active material preferably has an average particle size of 0.1 to 10 μm. If it is smaller than 0.1 μm, it is necessary to increase the amount of the conductive agent in order to ensure the current collecting performance, and the effective negative electrode capacity may be reduced. In addition, workability in manufacturing is greatly reduced. On the other hand, if it exceeds 10 μm, the current collecting performance may be lowered.

The negative electrode active material preferably has a specific surface area of 5 m ² / g or more and 100 m ² / g or less. If the specific surface area is less than 5 m ² / g, the current collecting performance may be lowered. On the other hand, if the specific surface area exceeds 100 m ² / g, it is necessary to increase the amount of the conductive agent, which may reduce the effective negative electrode capacity. In addition, workability in manufacturing is greatly reduced.

  The negative electrode layer can contain a binder. As the binder, for example, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVdF), ethylene-propylene-diene copolymer (EPDM), styrene-butadiene rubber (SBR), carboxymethylcellulose (CMC), or the like is used. be able to.

  The negative electrode layer can contain a conductive agent. Examples of the conductive agent include acetylene black, carbon black, and graphite.

  The mixing ratio of the negative electrode active material, the conductive agent and the binder is preferably in the range of 70 to 96% by weight of the negative electrode active material, 2 to 28% by weight of the conductive agent, and 2 to 28% by weight of the binder. If the amount of the conductive agent is less than 2% by weight, there is a possibility that the current collecting property is lacking and the large current characteristic is deteriorated. Further, if the amount of the binder is less than 2% by weight, the binding performance between the mixture layer and the current collector is lacking, and the cycle performance may be deteriorated. On the other hand, from the viewpoint of increasing the capacity, the amount of the conductive agent and the binder is preferably 28% by weight or less.

When a carbonaceous material is used as the negative electrode active material, the blending ratio of the carbonaceous material and the binder is preferably in the range of 90 to 98% by weight of the carbonaceous material and 2 to 10% by weight of the binder. In particular, the carbonaceous material is preferably in the range of 10 to 70 g / cm ^{2 on} one side in a state where the negative electrode is produced. The packing density is preferably in the range of 1.2 to 1.5 g / cm ³ .

  The thickness of the negative electrode layer is preferably in the range of 10 to 200 μm. Here, the thickness of the negative electrode layer means the distance between the surface of the negative electrode layer facing the separator and the surface of the negative electrode layer in contact with the current collector. By setting the thickness of the negative electrode layer within the range of 10 to 200 μm, the large current discharge characteristics and the cycle life can be improved. The thickness of the negative electrode layer is more preferably in the range of 30 to 100 μm. By setting it in this range, the large current discharge characteristics and the cycle life can be greatly improved.

2-2) Negative electrode current collector As the negative electrode current collector, a porous conductive substrate or a nonporous conductive substrate can be used. These conductive substrates can be formed from copper, copper alloy, aluminum, aluminum alloy, or nickel.

  Among these, it is preferable to use a conductive substrate having a two-dimensional porous structure in which holes having a diameter of 3 mm or less are present at a rate of 1 or more per 10 cm 2. That is, when the diameter of the hole of the conductive substrate is larger than 3 mm, there is a possibility that sufficient negative electrode strength cannot be obtained. On the other hand, when the proportion of holes having a diameter of 3 mm or less is smaller than the range, it is difficult to uniformly infiltrate the non-aqueous electrolyte into the electrode group, so that there is a possibility that a sufficient cycle life cannot be obtained. The diameter of the hole is more preferably in the range of 0.1 to 1 mm. Moreover, it is more preferable that the existence ratio of the holes is in the range of 10 to 20 per 10 cm 2.

  The conductive substrate having a two-dimensional porous structure in which holes having a diameter of 3 mm or less are present at a rate of 1 or more per 10 cm 2 is preferably in the range of 10 to 50 μm. If the thickness is less than 10 μm, sufficient negative electrode strength may not be obtained. On the other hand, when the thickness exceeds 50 μm, the battery weight and the thickness of the electrode group increase, and it may be difficult to sufficiently increase the weight energy density and volume energy density of the thin secondary battery.

  From the viewpoint of reliability during overdischarge, the negative electrode current collector is preferably aluminum or an aluminum alloy.

  The negative electrode current collector can also be obtained, for example, by forming a film on a resin sheet. The film forming means is not particularly limited. For example, metal powder coating (for example, screen printing), vapor deposition, sputtering, or the like can be employed.

  The thickness of the current collector is preferably in the range of 5 to 20 μm. This is because the negative electrode strength and weight reduction can be balanced within this range.

3) Separator As the separator, for example, a porous film containing polyethylene, polypropylene, or polyvinylidene fluoride (PVdF), a synthetic resin nonwoven fabric, or the like can be used. Among these, a porous film made of polyethylene, polypropylene, or both is preferable because it can improve the safety of the secondary battery.

  The thickness of the separator is preferably 30 μm or less. If the thickness exceeds 30 μm, the distance between the positive and negative electrodes may be increased and the internal resistance may be increased. Further, the lower limit value of the thickness is preferably 5 μm. If the thickness is less than 5 μm, the strength of the separator is remarkably lowered and an internal short circuit is likely to occur. The upper limit value of the thickness is more preferably 25 μm, and the lower limit value is more preferably 10 μm.

  The separator preferably has a heat shrinkage of 20% or less when it exists for 1 hour at 120 ° C. If the thermal shrinkage rate exceeds 20%, it may be difficult to make the adhesive strength between the positive and negative electrodes and the separator sufficient. The thermal shrinkage rate is more preferably 15% or less.

  As the separator, a porous thin film containing insulating particles such as ceramic fine particles (for example, SiO2, Al2O3, etc.) can be used. A porous thin film containing ceramic particles can be obtained, for example, by forming ceramic particles with a binder.

  The ceramic particle content in the separator is desirably 70% by weight or more and 96% by weight or less. This is due to the reason explained below. If the content of the ceramic particles is less than 70% by weight, there is a possibility that the effect of reducing the internal short-circuit occurrence rate when the separator is thinned and has a small area may not be obtained. On the other hand, when the content of the ceramic particles exceeds 96% by weight, the lithium ion permeability may be lowered or the nonaqueous electrolyte holding amount may be lowered. A more preferable range of the content is 80% by weight or more and 95% by weight or less.

  The thickness of the separator is preferably in the range of 5 to 30 μm. This is due to the following reason. As the thickness of the separator increases, the battery resistance after the hole is closed increases, so that the battery function can be quickly stopped. However, if the thickness exceeds 30 μm, the weight energy density and volume energy density of the secondary battery may be lowered. The upper limit value of the thickness is more preferably 25 μm, and the lower limit value is more preferably 10 μm.

  The separator preferably has a porosity in the range of 30 to 60%. This is due to the following reason. If the porosity is less than 30%, it may be difficult to obtain high electrolyte retention in the separator. On the other hand, if the porosity exceeds 60%, sufficient separator strength may not be obtained. A more preferable range of the porosity is 35 to 50%.

  The separator preferably has an air permeability of 600 seconds / 100 cm 3 or less. If the air permeability exceeds 600 seconds / 100 cm 3, it may be difficult to obtain high lithium ion mobility in the separator. Further, the lower limit value of the air permeability is preferably 100 seconds / 100 cm 3. This is because if the air permeability is less than 100 seconds / 100 cm 3, sufficient separator strength may not be obtained. The upper limit value of the air permeability is more preferably 500 seconds / 100 cm 3, and the lower limit value is more preferably 150 seconds / 100 cm 3.

  The separator is characterized in that at least one end extends from the positive electrode and the negative electrode. The separator to be extended is preferably extended by 0.25 mm or more from the negative electrode end. If the amount is too small, an internal short circuit is likely to occur. Further, it is desirable that a porous adhesive layer is also present in the extended portion of the separator. It is desirable that the separator extends from all sides in order to prevent internal short circuit.

4) Non-aqueous electrolyte As the non-aqueous electrolyte, a liquid, a polymer, or a solid can be used. Examples of the liquid non-aqueous electrolyte include those in which an electrolyte is dissolved in an organic solvent and those containing a room temperature molten salt.

(4-1) Nonaqueous Electrolyte Solution in which Electrolyte is Dissolved in Organic Solvent As the organic solvent, a known organic solvent can be used as a solvent for the nonaqueous electrolyte battery, and is not particularly limited. EC), cyclic carbonates such as propylene carbonate (PC), vinylene carbonate (VC), chain carbonates such as dimethyl carbonate (DMC), methyl ethyl carbonate (MEC), diethyl carbonate (DEC), tetrahydrofuran (THF), 2-methyl Examples include cyclic ethers such as tetrahydrofuran (2MeTHF), chain ethers such as dimethoxyethane (DME), γ-butyrolactone (BL), acetonitrile (AN), sulfolane (SL), and the like. These organic solvents can be used alone or in the form of a mixture of two or more.

  Among them, mixing of a first solvent composed of propylene carbonate (PC) and / or ethylene carbonate (EC) and one or more non-aqueous solvents (hereinafter referred to as second solvents) having a lower viscosity than PC and EC. It is preferable to use a non-aqueous solvent mainly composed of a solvent. The blending amount of the first solvent in the mixed solvent is preferably 10 to 80% by volume ratio. A more preferable amount of the first solvent is 20 to 75% by volume.

  Examples of the second solvent include chain carbonate, ethyl propionate, methyl propionate, γ-butyrolactone (γ-BL), acetonitrile (AN), ethyl acetate (EA), toluene, xylene, and methyl acetate (MA). Etc. These second solvents can be used alone or in the form of a mixture of two or more. Among these, chain carbonate is preferable. The second solvent preferably has a donor number of 16.5 or less.

  The viscosity of the second solvent is preferably 28 mp or less at 25 ° C.

Examples of the electrolyte include lithium perchlorate (LiClO ₄ ), lithium hexafluorophosphate (LiPF ₆ ), lithium tetrafluoroborate (LiBF ₄ ), lithium hexafluoroarsenide (LiAsF ₆ ), and trifluorometa. Examples thereof include lithium salts such as lithium sulfonate (LiCF ₃ SO ₃ ) and bistrifluoromethylsulfonylimitolithium [LiN (CF ₃ SO ₂ ) ₂ ], or a mixture thereof. LiPF ₆ and LiBF ₄ are particularly preferable. These may be used alone or in combination of two or more.

  The amount of electrolyte dissolved in the organic solvent is desirably 0.5 to 2 mol / L.

  A particularly preferred liquid non-aqueous electrolyte is one in which an electrolyte (for example, lithium salt) is dissolved in a mixed non-aqueous solvent containing γ-butyrolactone (BL), and the BL composition ratio is 40% by volume or more of the entire mixed non-aqueous solvent. 95% by volume or less.

  In the mixed non-aqueous solvent, it is preferable that the BL composition ratio is maximized. If the ratio is less than 40% by volume, gas tends to be generated at high temperatures. In addition, when the mixed non-aqueous solvent contains BL and cyclic carbonate, the ratio of the cyclic carbonate becomes relatively high, and thus the solvent viscosity may be remarkably increased. When the solvent viscosity increases, the conductivity and permeability of the liquid non-aqueous electrolyte decrease, so that the charge / discharge cycle characteristics, the large current discharge characteristics, and the discharge characteristics under a low temperature environment around −20 ° C. decrease. On the other hand, if the ratio exceeds 95% by volume, the reaction between the negative electrode and BL tends to occur, and the charge / discharge cycle characteristics may deteriorate. That is, when the negative electrode (for example, containing a carbonaceous material that occludes and releases lithium ions) reacts with BL to cause reductive decomposition of the liquid nonaqueous electrolyte, a coating that inhibits the charge / discharge reaction is formed on the surface of the negative electrode. The As a result, current concentration is likely to occur in the negative electrode, so that lithium metal is deposited on the negative electrode surface, or the impedance at the negative electrode interface is increased, the charge / discharge efficiency of the negative electrode is lowered, and charge / discharge cycle characteristics are degraded. A more preferable range is 60% by volume or more and 90% by volume or less. By setting it within this range, it is possible to further increase the effect of suppressing gas generation during high-temperature storage, and to further improve the discharge capacity in a low temperature environment around −20 ° C. A more preferable range is 75% by volume or more and 90% by volume or less.

  As a solvent mixed with BL, a cyclic carbonate is desirable in terms of increasing the charge / discharge efficiency of the negative electrode. As the cyclic carbonate, propylene carbonate (PC), ethylene carbonate (EC), vinylene carbonate (VC), trifluoropropylene carbonate (TFPC) and the like are desirable. In particular, when EC is used as a solvent mixed with BL, charge / discharge cycle characteristics and large current discharge characteristics can be significantly improved.

  Moreover, as another solvent mixed with BL, a third solvent consisting of at least one selected from the group consisting of PC, VC, TFPC, diethyl carbonate (DEC), methyl ethyl carbonate (MEC), and an aromatic compound, and EC The mixed solvent is desirable in terms of enhancing the charge / discharge cycle characteristics.

  Further, from the viewpoint of lowering the solvent viscosity, a low-viscosity solvent may be contained in an amount of 20% by volume or less. Examples of the low viscosity solvent include chain carbonates, chain ethers, cyclic ethers and the like.

  More preferable composition of the organic solvent is BL and EC, BL and PC, BL and EC and DEC, BL and EC and MEC, BL and EC and MEC and VC, BL and EC and VC, BL and PC and VC, or BL EC, PC, and VC. At this time, the volume ratio of EC is preferably 5 to 40% by volume. This is due to the following reason. If the EC ratio is less than 5% by volume, it may be difficult to cover the negative electrode surface densely with a protective film, so that the reaction between the negative electrode and BL occurs, and the charge / discharge cycle characteristics can be sufficiently improved. It can be difficult. On the other hand, if the EC ratio exceeds 40% by volume, the viscosity of the liquid non-aqueous electrolyte is increased and the ionic conductivity may be lowered. Therefore, sufficient charge / discharge cycle characteristics, large current discharge characteristics, and low temperature discharge characteristics are sufficiently obtained. It can be difficult to improve. A more preferable range of the EC ratio is 10 to 35% by volume. Moreover, it is preferable that the ratio of the solvent which consists of at least 1 type chosen from DEC, MEC, and VC shall be in the range of 0.5-10 volume%.

Examples of the electrolyte include the same ones as described above. LiPF ₆ and LiBF ₄ are particularly preferable.

  The amount of electrolyte dissolved in the organic solvent is desirably 0.5 to 2 mol / L.

  To the liquid non-aqueous electrolyte containing γ-BL, a surfactant such as trioctyl phosphate may be added in the range of 0.1 to 1% in order to improve the paintability with the separator.

  The amount of the liquid non-aqueous electrolyte is preferably 0.2 to 0.6 g per 100 mAh of battery unit capacity. This is due to the following reason. If the liquid nonaqueous electrolytic mass is less than 0.2 g / 100 mAh, the ionic conductivity of the positive electrode and the negative electrode may not be sufficiently maintained. On the other hand, if the liquid non-aqueous electrolytic mass exceeds 0.6 g / 100 mAh, the amount of electrolyte increases, and sealing by heat sealing may be difficult. A more preferable range of the liquid nonaqueous electrolytic mass is 0.4 to 0.55 g / 100 mAh.

(4-2) Room temperature molten salt Moreover, the room temperature molten salt containing lithium ion can be used as a non-aqueous electrolyte.

  The room temperature molten salt refers to a salt that is at least partially in a liquid state at room temperature, and the room temperature refers to a temperature range in which a power supply is assumed to normally operate. The temperature range in which the power supply is assumed to normally operate has an upper limit of about 120 ° C. and in some cases about 60 ° C., and a lower limit of about −40 ° C. and in some cases about −20 ° C.

Examples of the electrolyte include the same ones as described above. LiPF ₆ and LiBF ₄ are particularly preferable.

  The content of the lithium salt in the nonaqueous electrolyte is desirably 0.1 to 3 mol / L. This is due to the reason explained below. If the content of the lithium salt is less than 0.1 mol / L, the ionic conductivity of the non-aqueous electrolyte is lowered and there is a possibility that excellent large current / low temperature discharge characteristics cannot be obtained. On the other hand, when the content of the lithium salt exceeds 3 mol / L, the melting point of the non-aqueous electrolyte is increased and it may be difficult to maintain a liquid state at room temperature. A more preferable range of the lithium salt content is 1 to 2 mol / L.

Examples of the room temperature molten salt include those having a quaternary ammonium organic cation having a skeleton represented by the formula (1) or those having an imidazolium cation having a skeleton represented by the formula (2).

  However, in the formula (2), R1 and R2 are each CnH2n + 1 (n = 1 to 6), and may be the same or different, and R3 is H or CnH2n + 1 (n = 1). To 6).

  Examples of the quaternary ammonium organic cation having a skeleton represented by the formula (1) include imidazolium ions such as dialkylimidazolium and trialkylimidazolium, tetraalkylammonium ions, alkylpyridinium ions, pyrazolium ions, pyrrolidinium ions, pipettes. Examples include ridinium ions. In particular, an imidazolium cation having a skeleton represented by the formula (B) is preferable.

  Examples of the tetraalkylammonium ion include, but are not limited to, trimethylethylammonium ion, trimethylethylammonium ion, trimethylpropylammonium ion, trimethylhexylammonium ion, and tetrapentylammonium ion.

  Examples of the alkylpyridium ion include N-methylpyridinium ion, N-ethylpyridinium ion, N-propylpyridinium ion, N-butylpyridinium ion, 1-ethyl-2-methylpyridinium ion, 1-butyl-4-methylpyridinium ion Ions, 1-butyl-2,4 dimethylpyridinium ions and the like, but are not limited thereto.

  In addition, the normal temperature molten salt which has these cations may be used independently, or may be used in mixture of 2 or more types.

  The imidazolium cation having a skeleton represented by the formula (2) will be described. Examples of the dialkyl imidazolium ion include 1,3-dimethylimidazolium ion, 1-ethyl-3-methylimidazolium ion, 1-methyl-3-ethylimidazolium ion, 1-methyl-3-butylimidazolium ion, 1 -Butyl-3-methylimidazolium ion and the like. On the other hand, as the trialkylimidazolium ion, 1,2,3-trimethylimidazolium ion, 1,2-dimethyl-3-ethylimidazolium ion, 1, Examples thereof include, but are not limited to, 2-dimethyl-3-propylimidazolium ion and 1-butyl-2,3-dimethylimidazolium ion.

  In addition, the normal temperature molten salt which has these cations may be used independently, or may mix and use 2 or more types.

5) Exterior material A laminate sheet having a resin layer is used as the exterior material. Since this exterior material has flexibility, the non-aqueous electrolyte can be deformed. Moreover, since it is lightweight, the energy density per battery weight can be made high.

  As the exterior material, it is preferable to use an exterior material that includes a metal layer that serves to block moisture and a resin layer on the front and back surfaces of the metal layer.

  Examples of the metal layer include aluminum, stainless steel, iron, copper, and nickel. Among these, aluminum that is lightweight and has a high function of blocking moisture is preferable. The metal layer may be formed from one type of metal, but may be formed from a combination of two or more types of metal layers.

  Of the resin layers arranged on the front and back of the metal layer, the outer resin layer in contact with the outside serves to prevent and protect the metal layer from damage. This outer resin layer is formed of one type of resin layer or two or more types of resin layers. Examples of the material for the outer resin layer include polyethylene terephthalate and the like in addition to polyolefins such as polyethylene and polypropylene biaxially stretched to orient the polymer.

  On the other hand, the inner resin layer plays a role of preventing the metal layer from being corroded by the non-aqueous electrolyte. This inner resin layer is formed of one type of resin layer or two or more types of resin layers. Examples of the material for the inner resin layer include unstretched polyolefin such as polyethylene and polypropylene, and ethylene / vinyl acetate copolymer.

  In particular, the polyethylene is preferably a linear low density polyethylene (LLDPE) film (shape: linear, density: 0.915 to 0.945, crystallinity: 65 to 80%). The same is true for polypropylene.

  The thickness of the exterior material is preferably 0.5 mm or less. When the thickness of the exterior material exceeds 0.5 mm, the capacity per weight of the battery decreases. The thickness of the exterior material is preferably 0.3 mm or less, more preferably 0.25 mm or less, and most preferably 0.15 mm or less. On the other hand, if the thickness is less than 0.05 mm, deformation or breakage tends to occur. For this reason, the lower limit value of the thickness is preferably 0.05 mm. A more preferred lower limit is 0.08 mm, and a most preferred range is 0.1 mm.

6) Shape memory resin When shape memory resin is cooled by deformation, the deformed shape is fixed, but since the shape before deformation is memorized, the shape before deformation is heated by heating above the critical point. Refers to a polymer that returns to

  The shape memory resin may be a polymer that reversibly changes its shape by at least one factor such as temperature, pressure, humidity, solvent, pH, photoreaction, electricity, chelate formation, oxidation / reduction reaction, etc. It is not limited.

  For example, the polymer having shape memory ability with respect to temperature is not particularly limited as long as it is a resin that is in a glass state at room temperature and in a rubber state at room temperature or higher, but preferably polynorbornene, styrene-butadiene copolymer, polyurethane Polymers mainly composed of polyvinyl chloride, polymethyl methacrylate, polycarbonate, a crosslinked product of crystalline polyolefin, a crosslinked product of crystalline transpolyisoprene, a crosslinked product of crystalline transpolybutadiene, and the like are preferably used. The polymer having shape memory ability with respect to pressure is not particularly limited as long as it is a resin in a rubber state, and the above polymer is preferably used.

  Particularly preferred are cross-linked polyolefins such as cross-linked polyethylene and cross-linked polypropylene.

  Examples of the crosslinked polyethylene (XLPE) include those having a three-dimensional structure in which low density polyethylene (LDPE), medium density polyethylene (MDPE), and high density polyethylene (HDPE) are crosslinked. Among these, low density polyethylene (LDPE) is preferable. When LDPE is crosslinked, the gel fraction (crosslinking degree) is preferably 65% to 85%.

  In addition, LDPE, MDPE, and HDPE are classified by density as follows, and the manufacturing method and properties are also different.

LDPE density: 0.910 to 0.925
LDPE crystallinity: 60-70%
MDPE density: 0.926-0.940
MDPE crystallinity: 75-85%
HDPE density: 0.941 to 0.965
Crystallinity of HDPE: 85-95%
The term “crosslinking” refers to forming a chemical bond between molecules of a chain polymer so as to form a bridge.

  The polymer having shape memory ability with respect to humidity is not particularly limited as long as it is capable of shape memory utilizing properties such as swelling and shrinkage due to humidity, glass state and rubber state transition, but preferably a three-dimensionally cross-linked structural unit. What has it is good and a crosslinked polyvinyl alcohol, crosslinked polyamide, etc. are mentioned.

  The polymer having the shape memory ability with respect to the solvent is not particularly limited as long as the shape memory is utilized by utilizing the properties such as the swelling and shrinkage by the solvent and the glass state and the rubber state transition, but preferably the above-mentioned heat-sensitive shape memory. Those having a polymer or a three-dimensionally crosslinked structural unit are good, and examples thereof include crosslinked polyvinyl alcohol and crosslinked polyamide.

The polymer having shape memory ability with respect to pH is not particularly limited as long as it has a functional group that can be dissociated by pH change. These are those that reversibly cause membrane structure changes due to charge repulsion due to dissociation, imparting hydrophilicity, etc. by pH, and memorize the shape using properties such as swelling and shrinkage, glass state and rubber state transition, preferably A polymer having a functional group represented by the following formula is used.

  As a polymer having shape memory ability with respect to photoreaction, for example, utilizing hydrophilicity and charge repulsion caused by structural changes such as charge separation and sil-trans transition by photoreaction, swelling and shrinkage, glass state and rubber state transition The shape is memorized using such properties. It is not particularly limited as long as the functional group that undergoes charge separation by light in a specific wavelength region or a functional group that causes structural change such as cis-trans transition is contained in the polymer side chain and the main chain, preferably spiropyran, It is preferable that functional groups such as azobenzene and para-rose aniline are contained in the polymer side chain and main chain. In addition, the membrane material is not particularly limited as long as it is a polymer that reversibly changes depending on factors such as electricity, chelate formation, and oxidation / reduction reactions. These shape memory resins may be used alone, or may be at least two kinds of mixtures and copolymers.

  Hereinafter, an example of a manufacturing method in the case where a polymer having shape memory ability with respect to temperature is used as the shape memory resin will be described.

  First, a predetermined shape is stored in the shape memory resin. The temperature at this time is a temperature sufficiently exceeding the modification point of the shape memory resin. Thereafter, the shape memory resin is returned to room temperature and deformed from a predetermined shape (for example, an S shape) to a linear shape.

  Next, the power generation element is disposed between the inner surfaces of the exterior material. Thereafter, the three sides of the electrolyte solution injection port are bonded together by heat fusion through the shape memory resin, the positive electrode tab, and the negative electrode tab between the exterior materials, and then the electrolyte solution is injected. Is sealed by heat sealing to obtain a nonaqueous electrolyte battery.

  At this time, if the heat fusion temperature and the shape recovery temperature of the shape memory resin are approximately the same, a predetermined shape (for example, an S-shape) is restored at the time of heat fusion. When the shape recovery temperature is higher, the predetermined shape (for example, S-shape) is recovered by heating the peripheral edge with hot air from an air heater or an industrial dryer after heat fusion.

  As a simple process, it is preferable that the predetermined shape recovers during heat sealing. As a combination of such materials, polyethylene and polypropylene (temperature at heat fusion: 180 to 200 ° C.) are used for the inner resin layer, and cross-linked polyethylene, cross-linked polypropylene, transpolyisoprene, and styrene / butadiene are used for the shape memory resin. Examples thereof include a polymer (modification point: 120 ° C. to 150 ° C., heating temperature for modification is 150 to 200 ° C.).

(Second embodiment)
The structure of an example of the portable information device according to the second embodiment will be described with reference to FIGS.

  FIG. 5 is a schematic perspective view showing a state where the portable information device according to the second embodiment is deformed into an S shape. FIG. 6 is a schematic diagram of a side cross-section indicated by a dotted line C-C ′ in FIG. 5.

  As shown in FIG. 6, it is preferable that the nonaqueous electrolyte battery 14 and the inflection point of the mobile phone 12 substantially overlap each other. The display 16 and the CPU (central processing unit) 13 are preferably arranged so as to face the S-shaped inflection point.

  In order to give deformability, plastic or the like is used for the exterior of the mobile phone.

  Examples of portable information devices include mobile phones, PDAs, MP3 players, and the like.

  Examples will be described below, but the present invention is not limited to the examples described below unless the gist of the present invention is exceeded.

(Example 1) Shape memory resin-crosslinked polyethylene <Preparation of positive electrode>
As a positive electrode active material, 90% by weight of lithium cobalt oxide (LiCoO ₂ ) powder, 3% by weight of acetylene black, 3% by weight of graphite and 4% by weight of polyvinylidene fluoride (PVdF) are added to N-methylpyrrolidone (NMP) and mixed. A slurry was prepared. This slurry was applied to a current collector made of a porous aluminum foil (thickness: 15 μm) having a diameter of 0.5 mm at a rate of 10 per 10 cm 2, and then pressed to obtain an electrode density of 2.9 g. A positive electrode of / cm3 was produced.

<Production of negative electrode>
93% by weight of powder of mesophase pitch-based carbon fiber (carbon material having a fiber diameter of 8 μm, an average fiber length of 20 μm, and an average interplanar spacing (d002) of 0.3360 nm) heat-treated at 3000 ° C. as a negative electrode active material 7% by weight of polyvinylidene fluoride (PVdF) as an agent was mixed into a current collector made of a porous copper foil (thickness: 15 μm) having 10 mm 2 pores with a diameter of 0.5 mm. By coating, drying and pressing, a negative electrode having a structure in which the electrode density was 1.4 g / cm 3 and the negative electrode layer was supported on the current collector was produced.

<Separator>
A separator made of a polyethylene porous film having a thickness of 16 μm, a heat shrinkage of 20% at 120 ° C. for 1 hour, and a porosity of 50% was prepared.

<Preparation of non-aqueous electrolyte>
A non-aqueous electrolyte was prepared by dissolving 1.5 mol / l of lithium tetrafluoroborate (LiBF4) in a mixed solvent of ethylene carbonate (EC) and γ-butyrolactone (BL) (mixed volume ratio 25:75). .

<Production of electrode group>
The positive electrode and the negative electrode obtained as described above were laminated with the separator interposed therebetween to produce an electrode group having a thickness of 2 mm, a length of 6 cm, and a width of 3 cm.

<Memory of S-shape of shape memory resin>
The shape memory resin (crosslinked polyethylene) used was a frame having a circular cross section with a diameter of 1 mm. The shape memory resin memorized at 150 ° C. a shape capable of assisting the battery in forming and maintaining an S-shape when placed on the outer periphery of the electrode group. Thereafter, the shape was returned to be parallel to the plane.

<Battery assembly>
A laminate film exterior material was prepared by laminating a PET layer having a thickness of 100 μm, an Al layer having a thickness of 10 μm, and a PE layer having a thickness of 50 μm.

  An electrode group is arranged between the laminate film exterior materials, and further, the shape memory resin is arranged on the outer periphery of the electrode group, followed by a non-aqueous electrolyte pouring step, and a laminate film having a peripheral portion of 5 mm is formed. Heat fusion was performed at 180 ° C. for about 3 seconds. A frame-shaped shape memory resin is formed at the approximate center of the peripheral edge.

  Through the above process, an S-shaped non-aqueous electrolyte battery having a thickness of 3 mm, a length of 7 cm, and a width of 4 cm as shown in FIG. 3 was obtained.

(Example 2) Shape memory resin-crosslinked polypropylene
A nonaqueous electrolyte battery was produced in the same manner as in Example 1 except that the S-shaped memory was performed at 160 ° C. and the thermal fusion was performed at 190 ° C.

(Example 3) Shape memory resin-trans polyisoprene
A non-aqueous electrolyte battery was produced in the same manner as in Example 1 except that S-shaped memory was performed at 120 ° C. and heat fusion was performed at 180 ° C.

(Comparative Example 1) No shape memory resin A nonaqueous electrolyte battery was produced in the same manner as in Example 1 except that no shape memory resin was used.

(Comparative Example 2) Shape memory alloy-Ti-Ni (molar ratio 50:50) alloy
A non-aqueous electrolyte battery was produced in the same manner as in Example 1 except that S-shaped memory was performed at 500 ° C. and heated with hot air from a dryer after heat fusion.

  About the nonaqueous electrolyte battery of Examples 1-3 and Comparative Examples 1-2, after performing a bending test, the cycle test was done in a high-temperature, high-humidity environment.

  In the bending test, the center, which is the S-shaped inflection point, was first fixed. The straight line connecting one end and the center of the nonaqueous electrolyte battery was bent 1000 times so that the angle of the straight line connecting the other end and the center of the nonaqueous electrolyte battery was 0 ° to 30 °. The up and down direction for bending was the direction along the S-shape.

The cycle test was performed in an environment of a temperature of 60 ° C. and a humidity of 90%. Table 1 shows the discharge capacity retention ratio after 500 cycles with respect to the first cycle.

  As shown in Table 1, Examples 1-3 have a higher discharge capacity retention rate than Comparative Examples 1-2. Therefore, it can be seen that the nonaqueous electrolyte battery of the present invention has deformability and is excellent in sealing properties.

  As mentioned above, although embodiment of this invention was described, this invention is not restricted to these, In the category of the summary of the invention as described in a claim, it can change variously. In addition, the present invention can be variously modified without departing from the scope of the invention in the implementation stage. Furthermore, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment.

Schematic plan view of a flat non-aqueous electrolyte secondary battery according to the first embodiment Schematic of the side cross section indicated by the dotted line A-A 'in FIG. The perspective schematic diagram which shows the state which deform | transformed the non-aqueous electrolyte battery concerning 1st embodiment into S shape. Schematic diagram of the side cross section indicated by the dotted line B-B 'in FIG. The perspective schematic diagram which shows the state which deform | transformed the portable information device concerning 2nd embodiment into S shape. Schematic diagram of the side cross section indicated by the dotted line C-C 'in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Exterior material, 1a ... Outer resin layer, 1b ... Metal layer, 1c ... Inner resin layer, 2 ... Shape memory resin, 3 ... Positive electrode collector, 4 ... Positive electrode layer, 5 ... Separator, 6 ... Negative electrode layer, 7 DESCRIPTION OF SYMBOLS ... Negative electrode collector, 8 ... Electrode group, 9 ... Positive electrode tab, 10 ... Negative electrode tab, 12 ... Mobile phone, 13 ... CPU, 14 ... Nonaqueous electrolyte battery, 16 ... Display, 17 ... Key button

Claims (3)

A power generation element having a positive electrode, a negative electrode and a non-aqueous electrolyte;
A laminate exterior material that houses the power generation element and has a pair of inner resin layers that are heat-sealed to each other at the periphery,
A rod-shaped shape memory resin sandwiched between the inner resin layers, heat-sealed with the inner resin layer, and formed in the longitudinal direction of the peripheral edge;
A non-aqueous electrolyte battery comprising:   The non-aqueous electrolyte battery according to claim 1, wherein the shape memory resin has a cross-linked polyolefin, and the inner resin layer has a polyolefin. The nonaqueous electrolyte battery according to claim 1 or 2,
A central processing unit that drives the non-aqueous electrolyte battery as a power source;
A portable information device comprising:

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