Power storage body

Abstract

To achieve a flexible power storage body.SOLUTION: Unevenness is provided on an outer package. For example, unevenness is provided such that a cross-sectional shape of part of the outer package becomes a corrugation. The unevenness is not limited to a shape including a curve but may be a shape including a straight line like a rectangular wave or a triangular wave. By providing the unevenness on the outer package, the outer package becomes easily shrunk inside a bent section and easily extended outside the bent section.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] One embodiment of the present invention relates to a power storage unit and a manufacturing method thereof.

[0002] Note that one embodiment of the present invention is not limited to the above technical fields. The technical field of one aspect relates to an article, a method, or a manufacturing method. One aspect of the present invention is a process, machine, manufacture, or composition. Therefore, the invention disclosed herein more specifically relates to The technical field of one embodiment of the present invention is a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, Examples include a driving method thereof and a manufacturing method thereof. One embodiment of the present invention relates to a power storage unit and a manufacturing method thereof.

[0003] In this specification, the term "electricity storage unit" refers to elements and devices in general that have an electricity storage function. For example, the storage battery can be a battery, a primary battery, a secondary battery, a lithium-ion secondary battery, a lithium Examples include lithium-air secondary batteries, capacitors, and lithium-ion capacitors. In this specification, the electrochemical device refers to a device that utilizes a storage battery, a conductive layer, a resistor, a capacitor, etc. It also refers to electronic equipment, electrical equipment, and mechanical equipment. The device or the like may include a power storage unit according to one embodiment of the present invention. [Background technology]

[0004] In recent years, secondary batteries such as lithium-ion secondary batteries, lithium-ion capacitors, air batteries, etc. The development of various types of electricity storage devices is actively underway. Mu-ion secondary batteries are used in mobile phones, smartphones, laptops, etc. Electronic devices such as mobile information terminals, portable music players, digital cameras, medical devices, hardware Hybrid electric vehicle (HEV), electric vehicle (EV), or plug-in hybrid electric vehicle (PHE) With the development of the semiconductor industry, demand is rapidly increasing, including next-generation clean energy vehicles such as As a source of rechargeable energy, it has become indispensable in today's information society. are.

[0005] The characteristics required for lithium-ion batteries are high energy density and improved cycle characteristics. and improved safety and long-term reliability in various operating environments.

[0006] In recent years, flexible devices have become increasingly popular, such as head-mounted displays, which are used on the human body or curved surfaces. Furthermore, there is a demand for a flexible power storage device that can be attached to a curved surface. It is being considered.

[0007] An example of a lithium ion battery is a battery having at least a positive electrode, a negative electrode, and an electrolyte. (Patent Document 1). [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-9418 Summary of the Invention [Problem to be solved by the invention]

[0009] An object of one embodiment of the present invention is to provide a flexible power storage unit or the like. One of the objectives of the present invention is to realize a power storage unit that can be easily bent and stretched. One of the challenges is to realize a power storage device with excellent performance. One of the objectives is to provide a power storage device that is less likely to be defective. Another object is to provide a highly reliable power storage device. Another object is to provide a new power storage device or the like.

[0010] The description of these problems does not preclude the existence of other problems. It is not necessary for the present invention to solve all of these problems. The above will be made clear from the description, drawings, claims, etc. It is possible to extract other issues from the descriptions in the patent, claims, etc. [Means for solving the problem]

[0011] One aspect of the present invention is a battery comprising: a positive electrode and an outer casing having continuous irregularities on at least a part of its surface; The battery has a negative electrode, a separator, and an electrolyte solution, and the cross-sectional shape of the unevenness of the exterior body is wavy. This is a storage battery characterized by the above.

[0012] At least a part of the cross-sectional shape of the projections and recesses of the exterior body includes curves and / or straight lines. can be done.

[0013] As the exterior body of the electric storage unit, an exterior body having continuous irregularities on at least a part of the surface is used. This increases the flexibility of the exterior body. [Effects of the Invention]

[0014] It is possible to realize a flexible power storage unit, etc. It is possible to realize a power storage unit, etc. that can be easily bent and stretched. It is possible to realize a highly flexible power storage device. It is possible to realize a power storage unit, etc. It is possible to realize a power storage unit, etc. with good reliability Alternatively, a novel power storage device or the like can be provided.

[0015] The description of these effects does not preclude the existence of other effects. The embodiment does not necessarily have to have all of these effects. , the specification, drawings, claims, etc., and It is possible to extract other effects from the claims and other descriptions. [Brief explanation of the drawings]

[0016] [Figure 1] 1A and 1B are diagrams illustrating an example of a power storage unit. [Figure 2] FIG. 2 is a diagram illustrating a cross-sectional shape of a power storage unit. [Figure 3] 1A and 1B are diagrams illustrating an example of a power storage unit. [Figure 4] FIG. 2 illustrates an example of a positive electrode. [Figure 5] 1A to 1C illustrate an example of a positive electrode active material. [Figure 6] 4A to 4C are diagrams illustrating an example of a method for connecting a positive electrode lead to a positive electrode. [Figure 7] FIG. 2 illustrates an example of a negative electrode. [Figure 8] 1A to 1C illustrate an example of a negative electrode active material. [Figure 9] 1A to 1C illustrate an example of a method for manufacturing a power storage unit. [Figure 10] 1A to 1C illustrate an example of a method for manufacturing a power storage unit. [Figure 11] 1A to 1C illustrate an example of a method for manufacturing a power storage unit. [Figure 12] 1A to 1C illustrate an example of a method for manufacturing a power storage unit. [Figure 13] 10A and 10B are diagrams illustrating an example of a method for connecting lead terminals to a plurality of positive electrodes or a plurality of negative electrodes. [Figure 14] 1A to 1C illustrate an example of a method for manufacturing a power storage unit. [Figure 15] 1A to 1C illustrate an example of a method for manufacturing a power storage unit. [Figure 16] FIG. 2 is a diagram illustrating an example of a cross-sectional shape of an exterior body. [Figure 17] FIG. 10 is a diagram illustrating a cross section of overlapping power storage units. [Figure 18] 1A to 1C illustrate an example of a method for manufacturing a power storage unit. [Figure 19] 1A to 1C illustrate an example of a method for manufacturing a power storage unit. [Figure 20] FIG. 4 is a diagram illustrating an example of a lead terminal extraction direction. [Figure 21] FIG. 4 is a diagram illustrating an example of a lead terminal extraction direction. [Figure 22] FIG. 4 is a diagram illustrating the radius of curvature of a surface. [Figure 23] FIG. 1 is a diagram illustrating a cross section of a power storage unit. [Figure 24] 1A to 1C illustrate examples of electronic devices. [Figure 25] 1A to 1C illustrate examples of electronic devices. [Figure 26] 1A to 1C illustrate examples of electronic devices. [Figure 27] 1A and 1B are diagrams illustrating examples of vehicles using one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the following description, and various modifications in form and details are possible by those skilled in the art. Furthermore, the present invention should not be construed as being limited to the description of the following embodiments. It is not something that can be done.

[0018] In each drawing described in this specification, the size of each component, the thickness of a layer, or the area is The figures may be exaggerated or abbreviated for clarity. This is not limited to rules.

[0019] In this specification, ordinal numbers such as "first" and "second" are used to avoid confusion of components. It does not indicate any order or ranking such as the order of processes or stacking. In addition, even if a term is not accompanied by an ordinal number in this specification, etc., it is possible to avoid confusion of the constituent elements. To avoid this, ordinal numbers may be used in the claims.

[0020] In this specification, "parallel" means that two lines are at an angle of -10° to 10°. This refers to the state in which the object is arranged at an angle between -5° and 5°. Also, "perpendicular" and "orthogonal" mean, for example, that two straight lines are at an angle of 80° or more and 100° or less. This refers to a state in which the object is arranged at an angle between 85° and 95°.

[0021] In this specification and elsewhere, terms such as "identical," "same," and "equal" are used to refer to counting values ​​and measurement values. When we say "even" or "uniform," we mean plus or minus 20 unless otherwise specified. This includes a margin of error of %.

[0022] (Embodiment 1) A structural example of a power storage unit 100 of one embodiment of the present invention will be described with reference to drawings. 1A is a perspective view showing the appearance of the power storage unit 100. Also, FIG. 1A shows the X-axis direction, the Y-axis direction, and The arrows indicate the X-axis, Y-axis, and Z-axis directions, respectively. are directions perpendicular to each other. FIG. 1(B) is a top view of the power storage unit 100. FIG. 2(A) 1(B) is a cross-sectional view of a portion indicated by a dashed line X1-X2 parallel to the X-axis direction in FIG. FIG. 2B shows the portion indicated by the dashed line Y1-Y2 parallel to the Y-axis direction in FIG. 1B. 2(C) is a cross-sectional view of the Y3-Y4 line parallel to the Y-axis direction in FIG. 1(B). FIG. 2 is a cross-sectional view of the portion indicated by the dashed dotted line.

[0023] The power storage unit 100 of one embodiment of the present invention includes a positive electrode current collector 101 a and a positive electrode active material in an outer casing 107 . A positive electrode 101 having a material layer 101b, a separator 103, a negative electrode current collector 102a, and The negative electrode 102 has a negative electrode active material layer 102b, and an electrolyte solution 106. In this embodiment, for the sake of simplicity, an example in which a pair of positive electrode 101 and negative electrode 102 is housed in an exterior body is shown. However, in order to increase the capacity of the electricity storage body, multiple pairs of positive electrodes 101 and negative electrodes 102 are packaged in an exterior The positive electrode 101 is electrically connected to a positive electrode lead 104. The negative electrode 102 is electrically connected to the negative electrode lead 105. The lead 105 is also called a lead electrode or a lead terminal. A part of the negative electrode lead 105 is disposed on the outside of the exterior body. Discharge occurs via the positive electrode lead 104 and the negative electrode lead 105 .

[0024] In FIG. 2, a plate-shaped separator 103 is sandwiched between the positive electrode 101 and the negative electrode 102. However, one embodiment of the present invention is not limited thereto. For example, At least one of the electrodes may be covered with a pouch-shaped separator 103 .

[0025] In the power storage unit 100 of one embodiment of the present invention, the exterior body 107 has bellows-like projections and depressions. 1 is an enlarged cross-sectional view of a bent portion when the power storage unit 100 is bent in the Z-axis direction. By using a structure with bellows-like irregularities (hereinafter referred to as "bellows structure"), the inside of the bending part This allows exterior body 107 to be easily contracted on the side of the bent portion and easily stretched on the outside of the bent portion. By making the exterior body 107 have a bellows structure, it is possible to realize the power storage unit 100 having excellent flexibility. This can be done.

[0026] 1 and 2 show exterior body 107 having continuous unevenness in the X1-X2 direction. However, one aspect of the present invention is not limited to this. For example, a surface having continuous concaves and convexes only in the Y1-Y2 direction may be used. Alternatively, the surface may have continuous unevenness in both the X1-X2 direction and the Y1-Y2 direction. That's fine.

[0027] In addition, when the bending position of the power storage unit 100 is determined, only a part of the exterior body 107 is formed in a bellows structure. As an example, FIG. 3 shows a power storage unit 107 having a bellows structure in a part of its exterior body. 50 is shown in perspective view.

[0028] The power storage unit according to one embodiment of the present invention has a curvature radius of 30 mm or less when bent, preferably a curvature radius of 1 The exterior of the storage battery is made up of one or two films. The cross-sectional structure of the curved power storage unit is such that the positive electrode 101 and the negative electrode 102 are the outer casing. The structure is sandwiched between two curves of film.

[0029] Here, the radius of curvature of the surface will be explained with reference to FIG. 22. In FIG. 22(A), On a plane 1701 cutting a curved surface 1700, a curve 1702 included in the curved surface 1700 is Approximate a part of the arc of a circle, and set the radius of the circle as the radius of curvature 1703, and the center of the circle as the center of curvature 1 22(B) shows a top view of the curved surface 1700. 01 shows a cross-sectional view of a curved surface 1700. When a curved surface is cut by a plane, The radius of curvature of the curve that appears in the cross section will vary depending on the angle of the plane and the cutting position. In this specification and the like, the smallest radius of curvature is taken as the radius of curvature of the surface.

[0030] The battery is made of two films sandwiching the battery materials (1805) such as electrodes and electrolytes between them. When the film 1801 is placed on the side closer to the center of curvature 1800 of the capacitor, the radius of curvature 18 02 is smaller than the radius of curvature 1804 of the film 1803 on the side farther from the center of curvature 1800. (Fig. 23(A)). When the accumulator is bent to have an arc-shaped cross section, the center of curvature is close to 180°. The surface of the film that is closest to the center of curvature 180° is subjected to compressive stress, while the surface of the film that is far from the center of curvature 180° is subjected to compressive stress. Tensile stress is applied (Fig. 23(B)). By providing an uneven surface to the exterior body, Even if compressive or tensile stress is applied to the Therefore, in the power storage unit of one embodiment of the present invention, the bending of the exterior body on the side closer to the center of curvature can be prevented. The radius of curvature when bent can be set to 30 mm or less, preferably 10 mm or less.

[0031] The cross-sectional shape of the electricity storage unit is not limited to a simple arc shape, and may be a shape that includes a partial arc. For example, the shape shown in FIG. 23(C), a wavy shape (FIG. 23(D)), an S-shape, etc. When the curved surface of the power storage unit has a shape with multiple centers of curvature, The curvature radius at each center of curvature is the smallest, and the two outer surfaces The radius of curvature of the outer casing closest to the center of curvature of the outer casing is 30 mm or less, preferably 10 mm or less. It is possible.

[0032] <Configuration of each part and manufacturing method> Next, the structure and manufacturing method of each part of the power storage unit 100 will be described.

[0033] [1. Positive electrode] 4 shows an example of the positive electrode 101. FIG. 4(A) is a front view of the positive electrode 101, and FIG. 4(B) and 4(C) is a cross-sectional view of the area indicated by the dashed line A1-A2 in FIG. 4(A). The electrode 101 includes a positive electrode current collector 101a and a positive electrode active material layer 1 formed on the positive electrode current collector 101a. 4B shows one surface of the sheet-like positive electrode current collector 101a. 10 shows an example in which a positive electrode active material layer 101b is provided on the positive electrode layer 101b.

[0034] FIG. 4(C) shows an example in which positive electrode active material layers 101b are provided on both sides of a sheet-like positive electrode current collector 101a. By providing the positive electrode active material layer 101b on both sides of the positive electrode current collector 101a, The charge / discharge capacity of the positive electrode current collector 101a can be increased. Two positive electrodes 101 each having a positive electrode active material layer 101b formed on the positive electrode 101 were prepared. The electrodes may be stacked so that the surfaces on which the electrode active material layer 101b is not formed face each other.

[0035] The positive electrode active material layer 101b may be provided on the entire surface of the positive electrode current collector 101a. For example, the positive electrode lead 104 of the positive electrode current collector 101a may be provided. The positive electrode active material layer 101b is not provided on the portion in contact with the positive electrode (hereinafter also referred to as the "positive electrode tab"). It is good to have this configuration.

[0036] The positive electrode current collector 101a may be made of stainless steel, gold, platinum, zinc, iron, copper, aluminum, or titanium. Metals such as these and their alloys have high conductivity and are highly conductive with carrier ions such as lithium ions. Non-alloyed materials can be used. Also, silicon, titanium, neodymium, scandium Uses aluminum alloys containing elements such as tungsten and molybdenum that improve heat resistance. It may also be formed from a metal element that reacts with silicon to form silicide. Metal elements that react with silicon to form silicide include zirconium and titanium. , hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, The positive electrode current collector 101a may be in the form of a foil, a plate (sheet), a mesh, a plate, or a plate. Positive electrode current collector may be in the form of a punched metal, an expanded metal, or the like. The thickness of the positive electrode current collector 101a is preferably 5 μm or more and 30 μm or less. An undercoat layer made of graphite or the like may be provided on the surface of 101a.

[0037] The positive electrode active material layer 101b contains, in addition to the positive electrode active material, a binder ( The positive electrode active material layer 101b may contain a binder, a conductive additive for increasing the conductivity of the positive electrode active material layer 101b, and the like.

[0038] FIG. 5 shows the surface of the positive electrode active material layer 101b photographed with a scanning electron microscope (SEM). The photographs shown in Figure 5 were taken with a microscope. The porous layer 101b is made of a granular positive electrode active material 6003, a conductive additive 6004, and a binder 6005. Includes:

[0039] The positive electrode active material 6003 is a fired material obtained by mixing raw material compounds in a predetermined ratio and firing the mixture by an appropriate method. Granular positive particles consisting of secondary particles with an average particle size and particle size distribution that have been crushed, granulated, and classified by Therefore, the shape of the positive electrode active material is not limited to the shape shown in FIG. The shape of the positive electrode active material 6003 may be, for example, granular, plate-like, rod-like, cylindrical, powder-like, It can be made into any shape, such as a scale shape. It can also be made into a plate-like shape with an uneven surface, Those with a three-dimensional shape, such as those with fine irregularities on the surface or those with a porous shape may be.

[0040] The positive electrode active material 6003 may have an olivine type crystal structure, a layered rock salt type crystal structure, or or composite oxides having a spinel-type crystal structure. For example, LiFeO2, LiCoO2, LiNiO2, LiMn2O4, V2O5, Cr2 Compounds such as O5 and MnO2 are used.

[0041] In particular, LiCoO2 has a large capacity and is more stable in the air than LiNiO2. It is preferable because it has advantages such as being more thermally stable than LiNiO2.

[0042] In addition, lithium-containing materials with a spinel-type crystal structure containing manganese, such as LiMn2O4, The material contains a small amount of lithium nickel oxide (LiNiO2 or LiNi 1-x MO2 (M = Co, A Mixing with other additives such as manganese elution and electrolyte decomposition has the advantage of suppressing the dissolution of manganese. Yes, and preferable.

[0043] Alternatively, a composite material (general formula LiMPO4, where M is Fe(II), Mn(II), Co(II) Representative examples of the general formula LiMPO4 include: Examples include LiFePO4, LiNiPO4, LiCoPO4, LiMnPO4, and LiFe a Ni b PO4, LiFe a Co b PO4, LiFea Mn b PO4, LiNi a Co b PO4, LiNi a Mn b PO4 (a + b is less than or equal to 1, 0 < a < 1, 0 < b < 1), LiF e c Ni d Co e PO4, LiFe c Ni d ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​l SiO4, Li (2-j) Fe k Co l SiO4, Li (2-j ) Fe k Mn l SiO4, Li (2-j) Ni k Co l SiO4, Li (2-j) Ni k Mn l SiO4 (k + l is 1 or less, 0 < k < 1, 0 < l < 1), Li (2-j) Fe m N i n Co q SiO4, Li (2-j) Fe m Ni n Mn q SiO4, Li (2-j) Ni m Co n Mn q SiO4 (m + n + q is 1 or less, 0 < m < 1, 0 < n < 1, 0 < q < 1) [[ID=5​​​​​​​​​​​​​​​​​​​​​​​​​​​As for quality 6003, Li2MPO4F, Li2MP2O7, Li5MO4 (M=Fe, M n) Compounds represented by the general formula, perovskite-type fluorides such as NaFeF3 and FeF3 , TiS2, MoS2 and other metal chalcogenides (sulfides, selenides, tellurides), L Oxides with an inverse spinel crystal structure such as iMVO4, vanadium oxides (V2O5 , V6O 13 Materials such as manganese oxides and organic sulfur compounds can be used. This can be done.

[0047] In addition, the carrier ions are alkali metal ions other than lithium ions, alkaline earth metal ions, etc. In the case of metal ions, alkali metals (e.g., sodium) are used as the positive electrode active material instead of lithium. alkaline earth metals (e.g., calcium, strontium, barium, etc.), For example, NaFeO2 or Na2 / 3 [Fe 1 / 2 Mn 1 / 2 ]O2 and other sodium-containing layered oxides are used as the positive electrode active material 600 It can be used as 3.

[0048] The positive electrode active material 6003 may be a combination of the above materials. For example, a solid solution of a combination of the above materials can be used as the positive electrode active material 6003. For example, LiCo 1 / 3 Mn 1 / 3 Ni 1 / 3 A solid solution of O2 and Li2MnO3 is used as the positive electrode It can be used as the active material 6003 .

[0049] The average particle size of the primary particles of the granular positive electrode active material 6003 is 50 nm or more and 100 μm or less. It is recommended to use

[0050] Conductive additive 6004 includes acetylene black (AB), graphite particles, Carbon nanotubes, graphene, fullerenes, etc. can be used.

[0051] The conductive additive 6004 forms an electron conductive network in the positive electrode active material layer 101b. The conductive additive 6004 can maintain the electrical conduction path between the positive electrode active materials. By adding the conductive additive 6004 to the positive electrode active material layer 101b, a high electric current can be obtained. It is possible to realize a positive electrode active material layer 101b having electrical conductivity.

[0052] In addition, binder 6005 includes the typical polyvinylidene fluoride (PVDF) as well as poly Imide, polytetrafluoroethylene, polyvinyl chloride, ethylene propylene diene Polystyrene, styrene-butadiene rubber, acrylonitrile-butadiene rubber, fluororubber rubber, polyvinyl acetate, polymethyl methacrylate, polyethylene, nitrocellulose, etc. It can be used.

[0053] The content of the binder 6005 relative to the total amount of the positive electrode active material layer 101b is 1 wt % or more and 10 wt % or less. t% or less is preferable, 2 wt% to 8 wt% is more preferable, 3 wt% to 5 wt% is more preferable The following is more preferable: The content of the conductive additive relative to the total amount of the positive electrode active material layer 101b is: , preferably 1 wt% or more and 10 wt% or less, and more preferably 1 wt% or more and 5 wt% or less.

[0054] When the positive electrode active material layer 101b is formed by the coating method, the positive electrode active material 6003 and the conductive additive 6004 and binder 6005 are mixed to prepare a positive electrode paste (slurry), which is then used to form a positive electrode current collector. It is sufficient to apply it onto 101a and dry it.

[0055] [1.1. Connect the lead electrode to the positive electrode] After forming the positive electrode active material layer 101b on the positive electrode current collector 101a, A positive electrode lead 104 having a sealing layer 115 is connected to the tab (see FIG. 6(A)). The positive electrode tab and the positive electrode lead 104 are electrically connected by applying ultrasonic waves while applying pressure ( ultrasonic welding).

[0056] In addition, the positive electrode tab to which the positive electrode lead 104 is connected is not subjected to external force after the electricity storage unit is manufactured. The resulting stress can easily cause defects such as cracks and breaks.

[0057] Therefore, in this embodiment, an ultrasonic welding apparatus having a bonding die shown in FIG. 6(B) is used. In Fig. 6(B), for the sake of simplicity, only the upper and lower bonders of the ultrasonic welding equipment are used. Only the cutting die is shown.

[0058] a first bonding die 201 having a protrusion 203 and a second bonding die 202; The positive electrode tab and the positive electrode lead 104 are placed between the protrusion 203 and the positive electrode tab 104. By performing ultrasonic welding in this manner, a connection region 210 and a curved portion 220 are formed on the positive electrode tab. FIG. 6(C) is an enlarged perspective view of the connection region 210 and the curved portion 220 of the positive electrode tab. show.

[0059] By providing this curved portion 220, even if an external force is applied after the electricity storage unit 100 is manufactured, This can reduce the stress that occurs, thereby improving the reliability of the power storage unit 100. do.

[0060] The ultrasonic welding device having the bonding die shown in FIG. 6(B) can perform ultrasonic welding and bending. Since the formation of the portion 220 can be performed simultaneously, the secondary battery can be manufactured without increasing the number of processes. Alternatively, ultrasonic welding and forming of the curved portion 220 may be performed separately.

[0061] Furthermore, the positive electrode tab is not limited to being formed with the curved portion 220, and the material of the positive electrode current collector may be stainless steel. The positive electrode current collector is made of a strong material such as a resin, and the thickness of the positive electrode current collector is set to 10 μm or less. The structure may be such that stress caused by external force being applied from the outside after fabrication can be easily alleviated.

[0062] Of course, it goes without saying that a plurality of these may be combined to alleviate the stress concentration on the positive electrode tab. do not have.

[0063] In this way, a positive electrode 101 connected to a positive electrode lead 104 can be produced (see FIG. 6(D)).

[0064] [2. Negative electrode] Next, an example of a negative electrode constituting a power storage unit will be described with reference to FIG. 7. 7(A) is a front view of the negative electrode 102, and FIG. 7(B) and FIG. 7(C) are views of the negative electrode 102. 7A. The negative electrode 102 is a cross-sectional view of a portion indicated by a dashed line A3-A4 in FIG. The negative electrode active material layer 102b is formed on the negative electrode current collector 102a. FIG. 7B shows a negative electrode active material layer 102 formed on one surface of a sheet-shaped negative electrode current collector 102a. An example of providing 02b is shown. FIG. 7C shows an example in which negative electrode active material layers 102b are provided on both sides of a sheet-shaped negative electrode current collector 102a. By providing the negative electrode active material layers 102b on both sides of the negative electrode current collector 102a, The charge / discharge capacity of the negative electrode current collector 102a can be increased. Two negative electrodes 102 each having a negative electrode active material layer 102b formed on the negative electrode 102 were prepared. The electrodes may be stacked so that the surfaces on which the electrode active material layer 102b is not formed face each other.

[0065] The negative electrode active material layer 102b may be provided on the entire surface of the negative electrode current collector 102a. For example, the negative electrode lead 105 of the negative electrode current collector 102a may be provided. The negative electrode active material layer 102b is not provided on the portion that contacts the negative electrode (hereinafter also referred to as the "negative electrode tab"). It is good to have this configuration.

[0066] The negative electrode current collector 102a may be made of metal such as stainless steel, gold, platinum, zinc, iron, copper, or titanium, or These alloys and other materials have high conductivity and do not alloy with carrier ions such as lithium ions. Materials can be used that are formed from metal elements that react with silicon to form silicide. The metal element that reacts with silicon to form silicide is zirconium. Titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten The negative electrode current collector 102a may be in the form of a foil, a plate (sheet), or the like. Shapes such as mesh, punched metal, and expanded metal can be used as appropriate. The negative electrode current collector 102a preferably has a thickness of 5 μm or more and 30 μm or less. An undercoat layer may be provided on the surface of the negative electrode current collector 102a using graphite or the like. stomach.

[0067] FIG. 8 shows an example of a photograph of the surface of the negative electrode active material layer 102b taken with a scanning electron microscope. In the example, the negative electrode active material layer 102b contains a negative electrode active material 6103 and a binder 6105 (binding agent). However, a conductive additive may be added to the negative electrode active material layer 102b.

[0068] The negative electrode active material layer 102b is a layer in which lithium can be dissolved and deposited, or lithium ions can be inserted and extracted. There is no particular limitation on the material of the negative electrode active material layer 102b as long as it is a material that can be used. In addition to metals and lithium titanate, carbon-based materials and alloy-based materials, which are common in the field of energy storage, are also used. can be.

[0069] Lithium metal has a low oxidation-reduction potential (-3.045 V vs. the standard hydrogen electrode) and is lightweight and and high specific capacity per volume (3860mAh / g and 2062mAh / cm, respectively) 3 ) is therefore preferable.

[0070] Carbon materials include graphite, easily graphitizable carbon (soft carbon), and non-graphitizable carbon (hard carbon). Examples of such materials include graphene, carbon black, graphene nanotubes, graphene nanofibers, and graphene nanofibers.

[0071] Graphite includes mesocarbon microbeads (MCMB), coke-based artificial graphite, and pitch. Examples of such graphite include artificial graphite such as spheroidized artificial graphite, and natural graphite such as spheroidized natural graphite.

[0072] When lithium ions are inserted between the layers of graphite (when lithium-graphite intercalation compounds are formed), ), and shows a potential as noble as that of lithium metal (0.1 to 0.3 V vs. Li / Li + This allows the lithium-ion battery to exhibit a high operating voltage. Lead has a relatively high capacity per unit volume, small volume expansion, and is inexpensive. It is preferred because it has advantages such as higher safety compared to the metal.

[0073] As a negative electrode active material, it is possible to carry out charge-discharge reactions by alloying and dealloying reactions with lithium. A suitable alloy material or oxide can also be used. In some cases, the alloy material may be, for example, Mg, Ca, Al, Si, Ge, Sn, Pb, Contains at least one of As, Sb, Bi, Ag, Au, Zn, Cd, Hg, and In. These elements have a large capacity compared to carbon, and silicon in particular is theoretically The capacity is dramatically high at 4200mAh / g. Therefore, the use of silicon as the negative electrode active material As alloy materials using such elements, for example, Mg2Si, Mg 2Ge, Mg2Sn, SnS2, V2Sn3, FeSn2, CoSn2, Ni3Sn2, Cu6Sn5, Ag3Sn, Ag3Sb, Ni2MnSb, CeSb3, LaSn3, L Examples include a3Co2Sn7, CoSb3, InSb, and SbSn.

[0074] The negative electrode active material layer 102b may be made of SiO, SnO, SnO2, titanium oxide (TiO2 ), lithium titanium oxide (Li4Ti5O 12 ), lithium-graphite intercalation compound (Li x C6), niobium oxide (Nb2O5), tungsten oxide (WO2), molybdenum oxide (M Oxides such as SiO2 can be used.

[0075] The negative electrode active material layer 102b is made of a composite nitride of lithium and a transition metal, such as Li3N type Li with structure 3-x M x N (M=Co, Ni, Cu) can be used. For example, Li 2.6 Co 0.4 N3 has a large charge / discharge capacity (900mAh / g, 1890mAh / c m3 ) and is preferred.

[0076] When a composite nitride of lithium and a transition metal is used, the negative electrode active material contains lithium ions, The positive electrode active material is a combination of materials such as V2O5 and Cr3O8 that do not contain lithium ions. It is preferable that a material containing lithium ions is used as the positive electrode active material. By first removing the lithium ions contained in the positive electrode active material, As the nitride, a complex nitride of lithium and a transition metal can be used.

[0077] Furthermore, a material that causes a conversion reaction can also be used as the negative electrode active material layer 102b. For example, cobalt oxide (CoO), nickel oxide (NiO), iron oxide (FeO), etc. Alternatively, a transition metal oxide that does not undergo an alloying reaction with lithium may be used as the negative electrode active material. Further materials that undergo oxidation reactions include Fe2O3, CuO, Cu2O, and RuO2 , oxides such as Cr2O3, CoS 0.89 , NiS, CuS and other sulfides, Zn3N2, C Nitrides such as U3N and Ge3N4, phosphides such as NiP2, FeP2, and CoP3, and FeF3 This also occurs with fluorides such as BiF3.

[0078] When the negative electrode active material layer 102b is formed on the negative electrode current collector 102a by a coating method, The material 6103 and the binder 6105 are mixed to prepare a negative electrode paste (slurry), and the negative electrode The paste may be applied to the negative electrode 102a and dried. Good too.

[0079] Graphene may be formed on the surface of the negative electrode active material layer 102b. When the porous layer 102b is made of silicon, the absorption and release of carrier ions during the charge and discharge cycles Since the change in volume due to the deposition is large, the adhesion between the negative electrode current collector 102a and the negative electrode active material layer 102b is The negative electrode active material containing silicon is therefore When graphene is formed on the surface of the silicon layer 102b, the silicon body Even if the area changes, the adhesion between the negative electrode current collector 102a and the negative electrode active material layer 102b is not reduced. This is preferable because it can suppress the deterioration of the battery characteristics.

[0080] Furthermore, a coating of oxide or the like may be formed on the surface of the negative electrode active material layer 102b. The coating formed by the decomposition of the electrolyte releases the amount of charge consumed during its formation. In contrast, a film of oxide or the like is formed on the negative electrode active material in advance, and irreversible capacity is formed. By providing the electrode on the surface of the porous layer 102b, it is possible to suppress or prevent the occurrence of irreversible capacitance. Cut.

[0081] The coating that coats the negative electrode active material layer 102b may contain niobium, titanium, vanadium, tantalum, or the like. Ta, tungsten, zirconium, molybdenum, hafnium, chromium, aluminum or silicon oxide film, or a film containing one of these elements and lithium Such a coating is not susceptible to damage caused by the decomposition products of conventional electrolytes. This film is sufficiently dense compared to the coating formed on the outermost surface.

[0082] For example, niobium oxide (Nb2O5) has an electrical conductivity of 10 -9 Low S / cm and high insulation Therefore, the niobium oxide film prevents the electrochemical decomposition reaction between the negative electrode active material and the electrolyte. On the other hand, the lithium diffusion coefficient of niobium oxide is 10 -9 cm 2 / sec, which is high It has lithium ion conductivity, which allows lithium ions to pass through. Silicon oxide or aluminum oxide may also be used.

[0083] The coating that covers the negative electrode active material layer 102b can be formed by, for example, a sol-gel method. The sol-gel method is a method in which a solution of metal alkoxides or metal salts is subjected to a hydrolysis reaction. This method involves forming a gel that has lost its fluidity through a polycondensation reaction, and then baking this gel to form a thin film. The sol-gel method is a method for forming thin films from a liquid phase, so the raw materials must be homogenized at the molecular level. Therefore, the raw material of the metal oxide film at the solvent stage can be mixed with a negative electrode active material such as graphite. By adding a binder, the active material can be easily dispersed in the gel. A coating can be formed on the surface of the negative electrode active material layer 102b. By using the coating, This can prevent the capacity of the electricity storage unit from decreasing.

[0084] [2.1. Connect the lead electrode to the negative electrode] After forming the negative electrode active material layer 102b on the negative electrode current collector 102a, The negative electrode lead 105 having the sealing layer 115 is connected to the tab. The connection of 5 can be performed in the same manner as the connection of the positive electrode tab and the positive electrode lead 104.

[0085] [3. Separator] The separator 103 may be made of a material such as cellulose or polypropylene (PP). , polyethylene (PE), polybutene, nylon, polyester, polysulfone, polya Uses porous insulators such as chlorine nitrile, polyvinylidene fluoride, and tetrafluoroethylene. In addition, nonwoven fabrics such as glass fiber and composites of glass fiber and polymer fiber can be used. A diaphragm may also be used.

[0086] The positive electrode 101, the negative electrode 102, and the separator 103 are separated by the positive electrode 101 and the negative electrode 102. At this time, the positive electrode active material layer 101b and the negative electrode active material layer 10 9(A) shows a positive electrode active material 101a on one surface of the positive electrode current collector 101a. The cathode 101 has a negative electrode active material layer 101b formed thereon, and the negative electrode current collector 102a has a negative electrode active material layer 101b formed on one surface thereof. The figure shows a state in which a plate-shaped separator 103 is sandwiched between the negative electrode 102 on which the 02b is formed. The positive electrode lead 104 and the negative electrode lead 105 are arranged in different directions so as not to overlap each other. is doing.

[0087] The separator 103 is formed between at least the positive electrode active material layer 101b and the negative electrode active material layer 102b. It is preferable that the size is such that it completely covers one of the two.

[0088] FIG. 9(B) shows the state in which the positive electrode 101, the negative electrode 102, and the separator 103 are stacked. 9(C) is a perspective view showing the part indicated by the dashed line B1-B2 in FIG. Here, an example is shown in which a negative electrode 102 larger than a positive electrode 101 is stacked. However, a negative electrode 102 smaller than the positive electrode 101 may be stacked. The negative electrode 102 may be stacked on top of each other.

[0089] The shape of the separator 103 does not have to be a plate. For example, the separator 103 folded in half can be 03, one or both of the positive electrode 101 and the negative electrode 102 is folded in half. 10(A) shows the inside of the separator 103 folded in half. 1 shows how a positive electrode 101 is placed on the side of the negative electrode 102 and then the negative electrode 102 is placed on top of the positive electrode 101.

[0090] FIG. 10(B) shows a positive electrode 101 and a negative electrode 102 placed inside a folded separator 103. 10(B) is a perspective view showing a state in which the two 102 are stacked. 1 is a cross-sectional view of the portion indicated by the dashed line B3-B4 in FIG. The positive electrode 101 and the negative electrode 102 are stacked on top of each other, but the sizes of the positive electrode 101 and the negative electrode 102 are different. The folded separator 103 may be placed on either the positive electrode 101 or the negative electrode 102. It can be used for either or both.

[0091] In addition, a bag-shaped separator 103 is used to seal one or both of the positive electrode 101 and the negative electrode 102. It may be placed inside the bag-shaped separator 103. FIG. The figure shows how a positive electrode 101 is placed inside and then a negative electrode 102 is placed on top of it. The rater 103 may be in the form of an envelope.

[0092] The bifold, bag-shaped, and envelope-shaped separators are used to reduce the number of electrodes used in the storage battery to 101 positive electrodes. When the total number of the negative electrodes 102 is three or more, the productivity of the electricity storage unit can be increased.

[0093] In addition, if the number of electrodes used in the storage battery is three or more, a separator folded in a wavy (zigzag) shape is used. It is particularly effective to use a separator 103 folded in a wave shape. 1 is a perspective view showing how positive electrodes 101 and negative electrodes 102 are alternately stacked with one another via a hole. 12(A) shows a positive electrode 101 and a negative electrode 102 in which an active material layer is formed on one surface of a current collector. A positive electrode 101 and a negative electrode 102 each having an active material layer on both surfaces of a current collector are disposed between the electrodes. It shows a child.

[0094] FIG. 12(B) shows a positive electrode 101 and a negative electrode 102 connected together via a wave-shaped separator 103. 12(B) is a perspective view showing a state where a plurality of FIG. 5 is a cross-sectional view of the area indicated by the dashed dotted line along B5-B6.

[0095] The separator folded in a wave shape is used to divide the number of electrodes used in the electricity storage unit into positive electrodes 101 and negative electrodes 102. When the total number is three or more, the productivity of the electricity storage device can be further increased.

[0096] When a plurality of separators 103 are used in the power storage unit 100, the separators 103 are all made of the same material. Alternatively, separators 103 made of different materials may be used in combination. When a plurality of separators 103 are used in the power storage unit 100, all the separators 103 have the same shape. Alternatively, separators 103 of different shapes may be used in combination.

[0097] In addition, when a power storage unit having a plurality of positive electrodes 101 and a plurality of negative electrodes 102 is produced, the positive electrodes 10 1, after stacking the separator 103 and the negative electrode 102, multiple positive electrode tabs are combined into one It is preferable to connect the negative electrode tab 104 to the positive electrode lead 104 (see FIG. 13(A)). It is preferable to connect the positive electrode tab and the positive electrode lead 105 together. The connection between the negative electrode tab and the negative electrode lead 105 is performed by using a bonding die as described above. This can be done using an ultrasonic welding device having a The figure shows an enlarged perspective view of the region 210 and the curved portion 220. By connecting the negative electrode tabs to the negative electrode lead 104, multiple negative electrode tabs can be grouped together to form a single negative electrode lead. By connecting to the lead 105, productivity of the electricity storage unit can be improved.

[0098] [4. Exterior body] There are various types of secondary battery structures. In this embodiment, the outer casing 107 is formed The film for forming the exterior body 107 is a metal film (aluminum). Aluminum, stainless steel, nickel steel, etc.), plastic film made of organic material ( thermoplastic film), organic materials (organic resins and fibers, etc.) and inorganic materials (ceramics, etc.) Hybrid material films, carbon-containing films (carbon films, graphite A single layer film selected from the group consisting of films, etc., or a laminated film consisting of multiple of these films is used. Metal film is easy to process to give it an uneven surface, and the exterior body 107 with a bellows structure can be produced. Moreover, the metal film has an excellent heat dissipation effect. When a protrusion is formed, the surface area of ​​the exterior body 107 that is exposed to the outside air increases, thereby improving the heat dissipation effect. It can be done.

[0099] In addition, when the shape of the power storage unit 100 is changed by applying an external force, a part of the exterior body 107 Deformation or partial destruction may occur. This alleviates the strain caused by the stress applied to the exterior body 107 and increases the bending strength. Furthermore, even if the package is repeatedly bent and stretched, damage to the package is less likely to occur. This can improve the reliability of the power storage unit 100. Note that the strain is the standard (initial It is a measure of deformation that indicates the displacement of a material point within an object relative to its length (initial state). By forming a convex or concave portion, the influence of strain caused by applying force from the outside of the storage battery can be reduced. Therefore, it is possible to provide a highly reliable electricity storage unit. Cut.

[0100] 14(A) is a perspective view showing the appearance of a cylindrical exterior body 107 having a bellows structure. 4(B) shows a state in which the cylindrical exterior body 107 is deformed in the diameter direction (as if crushing a circle). The cylindrical exterior body 107 having a bellows structure is deformed, and the air is blown in from the inlet 119 in the forward direction. The electrode 101, separator 103, and negative electrode 102 are placed inside the exterior body 107 (FIG. 14(C) ).

[0101] Next, one of the two inlets 119 of the exterior body 107 is bonded by thermocompression. The sealing layer 115 provided on the lead electrode also melts, and the lead electrode and the outer casing 107 are fixed together. It is possible.

[0102] [5. Electrolyte] Next, a desired amount of electrolyte solution is introduced into the other inlet 11 under a reduced pressure atmosphere or an inert gas atmosphere. 9 into the exterior body 107.

[0103] The solvent of the electrolyte solution 106 used in the electricity storage unit 100 is preferably an aprotic organic solvent. For example, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate Carbonate, chloroethylene carbonate, vinylene carbonate, γ-butyrolactone , γ-valerolactone, dimethyl carbonate (DMC), diethyl carbonate (DE C), ethyl methyl carbonate (EMC), methyl formate, methyl acetate, methyl butyrate, 1 ,3-dioxane, 1,4-dioxane, dimethoxyethane (DME), dimethyl sulfone oxide, diethyl ether, methyl diglyme, acetonitrile, benzonitrile, tetrahydrofuran One of tetrahydrofuran, sulfolane, sultone, etc., or two or more of these Combinations and ratios may be used.

[0104] In addition, by using a polymer material that gels as a solvent for the electrolyte, safety against leakage etc. is improved. The safety of the secondary battery is improved. In addition, the secondary battery can be made thinner and lighter. Typical examples of materials include silicone gel, acrylic gel, acrylonitrile gel, and polyethylene gel. Examples include polyethylene oxide, polypropylene oxide, and fluorine-based polymers.

[0105] In addition, a flame-retardant and non-volatile ionic liquid (room-temperature molten salt) was used as the solvent for the electrolyte. By using multiple batteries, even if the internal temperature of the storage battery rises due to an internal short circuit or overcharging, This can prevent the storage battery from exploding or catching fire.

[0106] In addition, when lithium ions are used as a carrier, the electrolyte to be dissolved in the solvent is , such as LiPF6, LiClO4, LiAsF6, LiBF4, LiAlCl4, Li SCN, LiBr, LiI, Li2SO4, Li2B 10 Cl 10 , Li2B 12 Cl1 2, LiCF3SO3, LiC4F9SO3, LiC(CF3SO2)3, LiC(C2 F5SO2)3, LiN(CF3SO2)2, LiN(C4F9SO2)(CF3SO2 ), LiN(C2F5SO2)2, or two or more of these lithium salts Any combination and ratio may be used.

[0107] In addition, the electrolyte used in the electricity storage device does not contain granular waste or elements other than the constituent elements of the electrolyte (hereinafter simply referred to as It is preferable to use a highly purified electrolyte solution with a low content of impurities. Specifically, the weight ratio of impurities to the electrolyte is 1% or less, preferably 0.1% or less, more preferably 1% or less. It is more preferable that the content of vinylene carbonate in the electrolyte is 0.01% or less. Additives such as acetone may also be added.

[0108] Finally, the other inlet 119 is joined by thermocompression bonding. By using a cylindrical exterior body 107, the outer periphery of the exterior body 107 can be This reduces the number of joining steps for the parts, thereby improving the productivity of the power storage unit 100. The bellows structure improves the flexibility of the power storage unit 100, making it less susceptible to breakage and more reliable. It is possible to realize an electric body.

[0109] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0110] (Embodiment 2) In this embodiment, a power storage unit having a different structure from that of Embodiment 1 will be described with reference to FIG. Note that the power storage unit described in this embodiment has the same structure as the power storage unit described in Embodiment 1. Therefore, to avoid repetition of the explanation, In this embodiment, differences from the first embodiment will be described.

[0111] Fig. 15(A) is a front view of the power storage unit 150A. 10A illustrates an example of a method for manufacturing the power storage unit A. The method of forming the exterior body 107 is different from that of the body 100. The power storage unit 150A is made of two plate-shaped exterior bodies. The positive electrode 101, the separator 103, and the negative electrode 102 are arranged between the electrodes 107.

[0112] A positive electrode 101, a separator 103, and a negative electrode 102 are arranged between two plate-shaped exterior bodies 107. Thereafter, the outer periphery of the exterior body 107, except for the inlet 119 for introducing the electrolyte 106, is subjected to heat pressing. The inlet 119 is attached to the outer periphery of the plate 110 by welding (see FIG. 15(C)). During the thermocompression bonding, the sealing layer 115 provided on the lead electrode also melts and becomes the lead. The electrodes and the exterior body 107 can be fixed together. The portion where the outer periphery of the exterior body 107 is joined by thermocompression is shown as a joint 118 .

[0113] Then, a desired amount of electrolytic solution 106 is introduced into the inlet 1 under a reduced pressure atmosphere or an inert gas atmosphere. Then, the inlet 119 is finally bonded by thermocompression. In this manner, a power storage unit 150A can be manufactured (see FIG. 15(A)). ).

[0114] Furthermore, by providing irregularities on exterior body 107, the flexibility of power storage unit 150A is improved, making it less likely to break. Therefore, a highly reliable power storage unit can be realized. An example of this is shown in Figures 16(A) to 16(H). Figures 16(A) to 16(H) are the same as Figure 15. (B) is a cross-sectional view of the portion indicated by the dashed line C1-C2 or D1-D2. C2 indicates a cross section of exterior body 107 in the horizontal direction, and D1-D2 indicates a cross section of exterior body 107 in the vertical direction.

[0115] 16(A) to 16(C) show an example of a wavy cross-sectional shape with continuous curved concaves and convexes. 16(A) shows that the outer casing 107 has irregularities in the area other than the area overlapping with the joint 118 at the end thereof. However, as shown in FIG. 16(B), the unevenness may be provided up to the edge of the exterior body 107. In addition, when the position where the power storage unit is bent is clear, as shown in FIG. 16(C), A part of 7 may be provided with irregularities.

[0116] Furthermore, the pitch P of the irregularities is preferably one-tenth or less of the length L in the longitudinal cross section, It is more preferable that the pitch is 1 / 20 or less, and even more preferable that the pitch is 1 / 50 or less. In the horizontal cross section, P is preferably 1 / 10 or less of the length W, and more preferably 1 / 20 or less. It is more preferable that the ratio is 1 / 50 or less, and even more preferable that the ratio is 1 / 50 or less.

[0117] Here, the length L is the linear distance in the vertical direction of the area surrounded by the joint 118. L is the linear distance in the vertical direction of the region where the positive electrode 101 and the negative electrode 102 are provided. , the length W is the lateral linear distance of the area surrounded by the joint 118. Alternatively, the length W is This is the linear distance in the horizontal direction between the regions where the positive electrode 101 and the negative electrode 102 are provided (FIG. 15( See A). ).

[0118] The height difference A of the unevenness is preferably 5 times or more, more preferably 10 times or more, the thickness T of the exterior body. It is preferable that the ratio is 20 times or more (see FIG. 16(A)).

[0119] In addition, the pitch P and height difference A do not need to be uniform over the entire length of the length L or length W. For example, the pitch P and / or the height difference A may be varied depending on the location of the exterior body. That is, the pitch P and / or the height difference A may have multiple values. The pitch P and / or the height difference A may be varied continuously in the vertical and / or horizontal directions. stomach.

[0120] Note that when the power storage unit of one embodiment of the present invention is bent, the pitch P on the inside of the bent portion is The pitch P on the outside of the bent portion may be smaller than the pitch P on the inside of the bent portion. It may be larger than the pitch P.

[0121] The cross-sectional shape of the unevenness provided on the exterior body 107 is not limited to a shape including a curve, and may be any of the shapes shown in FIGS. 16(D) to 16(E). It may be a shape including straight lines such as 16(F). For example, it may be a rectangular wave or a triangular wave. Also, as shown in Fig. 16(G), it may have a shape that combines curved lines and straight lines. Furthermore, the exterior body 107 does not have continuous unevenness in at least one of the horizontal and vertical directions. In this case, the cross-sectional shape in the direction in which the continuous unevenness is not provided is as shown in FIG. 16(H). The cross sections illustrated in Figures 16(a) to 16(h) can be used in appropriate combination.

[0122] FIG. 17 shows a stack of two power storage units 150A, each having a package 107 with continuous triangular wave-like irregularities. As shown in FIG. 17, when a plurality of power storage units are stacked, By adjusting the uneven shape and pitch P of each exterior body, the power storage units can be fitted together. By fitting the concave and convex portions of the exterior body together, it is possible to prevent misalignment of multiple power storage units. This can be done.

[0123] In addition, in FIG. 17, the power storage unit 150A is shown as an example of the power storage unit with the exterior bodies engaged. The same effect can be achieved with a power storage unit such as the power storage unit 100.

[0124] Fig. 18(A) is a front view of the power storage unit 150B. 15A and 15B are diagrams illustrating an example of a method for manufacturing the power storage unit 100 and the power storage unit B. The method of forming the exterior body 107 of the power storage unit 150B is different from that of the power storage unit 150A. The positive electrode 101, the separator 103, and the negative electrode 102 are arranged between the bodies 107.

[0125] The positive electrode 101, the separator 103, and the negative electrode 102 are placed between the folded exterior body 107. After that, the outer periphery of the exterior body 107 except for the inlet 119 for introducing the electrolyte 106 is heat-pressed. (See FIG. 18(C)).

[0126] Then, a desired amount of electrolytic solution 106 is introduced into the inlet 1 under a reduced pressure atmosphere or an inert gas atmosphere. Then, the inlet 119 is finally bonded by thermocompression. In this manner, a power storage unit 150B can be manufactured (see FIG. 18(A)). ).

[0127] In addition, since the power storage unit 150B is manufactured using the exterior body 107 folded in half, The length of the joint 118 can be made shorter than 150A. According to one embodiment of the present invention, productivity of a power storage unit can be increased. do.

[0128] In addition, similar to the power storage unit 150A, the cross-sectional shape shown in FIGS. 16(A) to 16(H) is folded in half. It can be used for the outer casing 107.

[0129] 19(A) is a front view of the power storage unit 150C. Also, FIG. 19(B) is a front view of the power storage unit 150C. 10A and 10B are diagrams illustrating an example of a method for manufacturing a power storage unit 150C. A cylindrical exterior body 107 having two openings is used.

[0130] After arranging the positive electrode 101, the separator 103, and the negative electrode 102 inside the cylindrical outer casing 107, The cylindrical outer casing is formed by leaving an inlet 119 for introducing the electrolyte 106 in a part of one opening. The opening of 107 is bonded by thermocompression (see FIG. 19(C)).

[0131] Then, a desired amount of electrolytic solution 106 is introduced into the inlet 1 under a reduced pressure atmosphere or an inert gas atmosphere. Then, the inlet 119 is finally bonded by thermocompression. In this manner, a power storage unit 150C can be manufactured (see FIG. 19(A)). ).

[0132] Since the power storage unit 150C is manufactured using a cylindrical exterior body 107, the power storage unit 150A and The length of the joint 118 can be made shorter than that of the power storage unit 150B. According to one embodiment of the present invention, productivity of a power storage unit can be increased. can be done.

[0133] 16(A) to 16(H) are cylindrical in shape, as in the case of the power storage unit 150A. It can be used for the exterior body 107.

[0134] (Embodiment 3) In this embodiment, an example of the lead terminal lead-out direction and the external shape of the power storage unit is shown in FIG. This will be explained using FIGS. 20(A) to 20(D) and FIGS. 21(A) to 21(D).

[0135] 20A is a front view of the power storage unit 200A. The power storage unit 200A has a positive electrode lead 104 and A negative electrode lead 105 is arranged on the same side of the exterior body 107 .

[0136] 20B is a front view of the power storage unit 200B. The power storage unit 200B has a positive electrode lead 104 and Negative electrode leads 105 are arranged on different sides of the exterior body 107 .

[0137] In addition, in the power storage unit according to one embodiment of the present invention, the positive electrode lead 104 and the negative electrode lead 105 are For example, as in the case of a power storage unit 200C shown in FIG. 20(C), One positive electrode lead 104 and two negative electrode leads 105 may be arranged on different sides. In addition, two positive electrode leads 104 and one negative electrode lead 105 are arranged on different sides. That's fine.

[0138] For example, as shown in FIG. 20(D), a power storage unit 200D has one positive electrode lead 104 and two The negative electrode leads 105 may be arranged on the same side. The pole leads 105 may be arranged on the same side.

[0139] For example, as in the case of a power storage unit 200E shown in FIG. 21(A), positive electrode leads 10 are attached to four different sides. 4 and a negative electrode lead 105 may be disposed.

[0140] For example, as shown in FIG. 21(B), a power storage unit 200F has a plurality of positive electrode leads 104 and a plurality of A negative electrode lead 105 may be provided.

[0141] The external shape of a power storage unit according to one embodiment of the present invention is not limited to a rectangular shape. It may have a curved portion, such as a power storage unit 200G shown in FIG. 1(D) shows a storage battery 200H, which has a shape with a part missing from the above. It's fine.

[0142] In the power storage unit according to one embodiment of the present invention, the number of lead terminals to be used and their lead-out positions can be set arbitrarily. According to one embodiment of the present invention, a power storage unit with high design freedom can be provided. can be done.

[0143] (Fourth embodiment) The power storage unit according to one embodiment of the present invention can be used as a power storage device for various electronic devices driven by power. 24 to 27 illustrate examples of electronic devices using a power storage device according to one embodiment of the present invention. A specific example is given below.

[0144] Examples of electronic devices using a power storage device according to one embodiment of the present invention include display devices such as televisions and monitors, Lighting equipment, desktop or notebook personal computers, word processors , stored on a recording medium such as a DVD (Digital Versatile Disc), Image playback devices that play still or moving images, portable CD players, radios, tape players Coder, headphone stereo, stereo, table clock, wall clock, cordless telephone handset, Transceivers, mobile phones, car phones, portable game consoles, tablet devices, pachinko machines Large game consoles, calculators, personal digital assistants, electronic organizers, e-books, electronic translators, voice input High frequency heating of equipment, video cameras, digital still cameras, electric shavers, microwave ovens, etc. appliances, electric rice cookers, electric washing machines, electric vacuum cleaners, water heaters, electric fans, hair dryers, air conditioners air conditioning equipment such as air conditioners, humidifiers, dehumidifiers, dishwashers, dish dryers, clothes dryers, cloth dryers, Dryers, electric refrigerators, electric freezers, electric refrigerator-freezers, freezers for DNA storage, flashlights, Examples include tools such as chainsaws, smoke detectors, and medical equipment such as dialysis machines. Guiding lights, traffic lights, conveyor belts, elevators, escalators, industrial robots, power storage systems, power leveling and industrial equipment such as energy storage devices for smart grids. In addition, moving objects propelled by electric motors using power from a power storage device are also included in the category of electronic devices. The above-mentioned mobile objects include, for example, electric vehicles (EVs), internal combustion engines, and Hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs) , tracked vehicles in which these tires and wheels are converted into tracks, and motorized vehicles including electrically assisted bicycles. Bicycles, motorcycles, electric wheelchairs, golf carts, small or large boats, submarines, helicopters Examples include robots, aircraft, rockets, satellites, space probes, planetary probes, and spacecraft. do.

[0145] Further, the power storage device according to one embodiment of the present invention may be applied to an inner or outer wall of a house or a building, or to the interior of a vehicle. Alternatively, it may be incorporated along the curved surface of the exterior.

[0146] FIG. 24A shows an example of a mobile phone. The mobile phone 7400 has a housing 7401. In addition to the display unit 7402 incorporated in the The mobile phone 7400 is equipped with a speaker 7405, a microphone 7406, and the like. It has device 7407.

[0147] FIG. 24B shows the mobile phone 7400 in a bent state. When the entire device is deformed by an external force and curved, the power storage device installed inside 7407 is also bent. At this time, the bent state of the power storage device 7407 is shown in FIG. ) shown.

[0148] FIG. 24(D) shows an example of a bangle-type display device. The portable display device 7100 includes: The device includes a housing 7101, a display portion 7102, operation buttons 7103, and a power storage device 7104. FIG. 24E shows the bent state of the power storage device 7104.

[0149] FIG. 24(F) shows an example of a wristwatch-type portable information terminal. The portable information terminal 7200 is , a housing 7201, a display unit 7202, a band 7203, a buckle 7204, and an operation button 72 05, input / output terminal 7206, etc.

[0150] The portable information terminal 7200 is capable of carrying out mobile phone calls, e-mails, viewing and creating documents, playing music, and internet access. - It can run various applications such as internet communication and computer games. do.

[0151] The display surface of the display unit 7202 is curved, and the display can be performed along the curved display surface. The display portion 7202 is provided with a touch sensor, and can be used to touch the screen with a finger or a stylus. For example, the icon 7207 displayed on the display unit 7202 can be operated by You can launch the application by touching it.

[0152] The operation button 7205 is used to set the time, turn the power on and off, and turn wireless communication on and off. It has various functions such as operation, silent mode activation and deactivation, power saving mode activation and deactivation, etc. For example, an operation system built into the portable information terminal 7200 can The system also allows the functions of the operation buttons 7205 to be freely set.

[0153] In addition, the mobile information terminal 7200 is capable of performing standardized short-range wireless communication. For example, by communicating with a wireless headset, hands-free operation is possible. You can also make calls.

[0154] The portable information terminal 7200 also has an input / output terminal 7206, and a connector for connecting to other information terminals. Data can be exchanged directly via the input / output terminal 7206. The charging operation can be performed by wireless power supply without going through the input / output terminal 7206. It is also possible.

[0155] The portable information terminal 7200 includes the power storage device of one embodiment of the present invention. The power storage device 7104 shown in FIG. 7 is mounted in a curved state inside the housing 7201 or in a band 7 203 in a bendable state.

[0156] FIG. 24G shows an example of a wristband-type display device. The display device 7300 includes a display unit 7 304 and includes the power storage device of one embodiment of the present invention. The display unit 7304 may be provided with a touch sensor, and may function as a portable information terminal. It is also possible.

[0157] The display surface of the display unit 7304 is curved, and images can be displayed along the curved display surface. The display device 7300 can also communicate with the display device 7300 by short-distance wireless communication according to a communication standard. The situation can be changed.

[0158] The display device 7300 is also equipped with an input / output terminal, and can be directly connected to other information terminals via a connector. It is also possible to charge the device via the input / output terminals. The charging operation may be performed by wireless power supply without using the input / output terminals.

[0159] 25(A) and 25(B) show an example of a foldable tablet terminal. The tablet terminal 9600 shown in FIG. 25(A) and FIG. 25(B) includes a housing 9630a, a housing a movable part 9640 connecting the housing 9630a and the housing 9630b; a display part 96 31a and a display unit 9631 having a display unit 9631b, a display mode changeover switch 962 6. Power switch 9627, power saving mode switch 9625, fastener 9629, 25A shows the tablet terminal 9600 in an open state. 25(B) shows the tablet terminal 9600 in a closed state.

[0160] The tablet terminal 9600 also includes a battery storage device inside the housing 9630a and the housing 9630b. The power storage device 9635 is connected to the housing 9630a through a movable portion 9640. It is provided across the housing 9630b.

[0161] A part of the display unit 9631a can be used as a touch panel area 9632a. By touching the operation keys 9638, data can be input. In 1a, for example, half of the area has a display function only, and the other half The display unit 963 has a touch panel function, but is not limited to this. The entire area of ​​the display unit 96 may have a touch panel function. The entire surface of 31a is displayed as a keyboard button to serve as a touch panel, and the display part 9631b is displayed. It can be used as a screen.

[0162] In addition, in the display unit 9631b, as in the display unit 9631a, a part of the display unit 9631b The area 9632b of the touch panel can be used as the keyboard of the touch panel. By touching the area where the display switch button 9639 is displayed with your finger or a stylus, A keyboard can be displayed on the display portion 9631b.

[0163] In addition, touch panel area 9632a and touch panel area 9632b can be touched simultaneously. You can also input characters using the touchpad.

[0164] A display mode changeover switch 9626 changes the display orientation between portrait and landscape. You can select between black and white and color display. The touch 9625 detects when in use by the light sensor built into the tablet terminal 9600. The display brightness can be optimized according to the amount of external light. In addition to optical sensors, other sensors such as gyros and acceleration sensors that detect tilt are also available. The device may be built-in.

[0165] FIG. 25A shows an example in which the display area of ​​the display portion 9631b is the same as that of the display portion 9631a. However, there is no particular limitation, and one size may be different from the other, and the display For example, one display panel may be capable of displaying images with higher resolution than the other. It may also be possible to use the following.

[0166] FIG. 25(B) shows the tablet terminal in a closed state, and the tablet terminal includes a housing 9630, a solar cell 96 33, a charge / discharge control circuit 9634 including a DC / DC converter 9636. The power storage unit of one embodiment of the present invention can be used for the device 9635.

[0167] In addition, since the tablet terminal 9600 can be folded in half, when not in use, the housing 9630a and The housing 9630b can be folded so that the housing 9630a and the housing 9630b overlap each other. Since the display units 9631a and 9631b can be protected, the durability of the tablet terminal 9600 can be improved. Furthermore, the power storage device 9635 using the power storage unit of one embodiment of the present invention can It has flexibility and the charge / discharge capacity is not easily reduced even when repeatedly bent and stretched. It can provide excellent tablet devices.

[0168] In addition, the tablet terminals shown in Figures 25(A) and 25(B) can be used in various Functions that display information (still images, videos, text images, etc.), calendars, dates, or times The function to display information on the display unit, and the function to input or edit the information displayed on the display unit. It has input functions, functions to control processing using various software (programs), etc. It is possible.

[0169] The solar cell 9633 attached to the surface of the tablet terminal supplies power to the touch panel, The solar cell 9633 can be supplied to a display unit, a video signal processor, or the like. By providing the power storage device 9635 on one or two surfaces of the body 9630, the power storage device 9635 can be efficiently charged. The power storage device 9635 is preferably a lithium-ion battery. The use of the above has the advantage of enabling miniaturization.

[0170] The configuration and operation of the charge / discharge control circuit 9634 shown in FIG. 25(B) are shown in FIG. A block diagram is shown in FIG. 25(C) and will be described. In FIG. 25(C), a solar cell 9633, a power storage device 96 35, DC-DC converter 9636, converter 9637, switches SW1 to SW3, The display unit 9631 is shown, along with a power storage device 9635, a DC-DC converter 9636, The converter 9637 and the switches SW1 to SW3 constitute a charge / discharge control circuit shown in FIG. This corresponds to 9634.

[0171] First, an example of operation when power is generated by the solar cell 9633 using external light will be described. The power generated by the solar cell is converted to a voltage to charge the storage device 9635. The converter 9636 increases or decreases the voltage. When power is used from the battery 9633, the switch SW1 is turned on, and the converter 963 7, the voltage is increased or decreased to the voltage required for the display unit 9631. When not displaying in 1, SW1 is turned off and SW2 is turned on to charge the power storage device 9635. The charging may be performed in the above manner.

[0172] The solar cell 9633 is shown as an example of a power generating means, but is not particularly limited thereto. Power storage using other power generation methods such as piezoelectric elements and thermoelectric conversion elements For example, the power may be transmitted and received wirelessly (contactlessly). It is also possible to combine it with a contactless power transmission module that charges the battery, or other charging means. You may do so.

[0173] Another example of electronic equipment is shown in FIG. 26. In FIG. 26, a display device 8000 is a display device according to one embodiment of the present invention. 8 is an example of an electronic device using a power storage device 8004 according to an embodiment. 8000 corresponds to a display device for receiving TV broadcasts, and includes a housing 8001, a display unit 8002, and a speaker unit. The power storage device 8004 according to one embodiment of the present invention includes a housing 8003, a power storage device 8004, and the like. The display device 8000 is provided inside a body 8001. The display device 8000 receives power from a commercial power source. Alternatively, the power stored in the power storage device 8004 can be used. Even when power cannot be supplied from a commercial power source due to a power outage or the like, the present invention The power storage device 8004 can be used as an uninterruptible power supply, thereby enabling the use of the display device 8000. do.

[0174] The display unit 8002 includes a liquid crystal display device, an emitting device having a light emitting element such as an organic EL element in each pixel, and Device, electrophoretic display device, DMD (Digital Micromirror Device) ce), PDP (Plasma Display Panel), FED (Field A semiconductor display device such as a reflective LED (emission display) can be used.

[0175] In addition to TV broadcast reception, display devices are also used for personal computers and advertising displays. , including all display devices for displaying information.

[0176] In FIG. 26, a stationary lighting device 8100 includes a power storage device 81 according to one embodiment of the present invention. 8101, a housing 8102, a light source 8103, and a light source 8104. 26, the power storage device 8103 is mounted in a housing 81. 8101 and a light source 8102 are installed inside a ceiling 8104. However, the power storage device 8103 may be provided inside the housing 8101. The device 8100 can receive power from a commercial power source or store power in a power storage device 8103. Therefore, if the power supply from the commercial power source is interrupted due to a power outage, etc., Even when power cannot be received, the power storage device 8103 of one embodiment of the present invention can be used as an uninterruptible power supply. This allows the lighting device 8100 to be used.

[0177] 26 shows an example of a fixed lighting device 8100 provided on a ceiling 8104. However, in the power storage device of one embodiment of the present invention, the side wall 8105, the floor 8106, and the like are not included in the ceiling 8104. 106, it can be used for a fixed lighting device provided in a window 8107, etc., or it can be used for a tabletop lighting device. It can also be used in lighting devices of this type.

[0178] The light source 8102 may be an artificial light source that artificially obtains light using electricity. Specifically, incandescent lamps, fluorescent lamps and other discharge lamps, and light-emitting devices such as LEDs and organic EL elements The element is an example of the artificial light source.

[0179] In FIG. 26, an air conditioner having an indoor unit 8200 and an outdoor unit 8204 is 8 is an example of an electronic device including a power storage device 8203 of one embodiment of the present invention. The device 8200 includes a housing 8201, an air outlet 8202, a power storage device 8203, and the like. 8 illustrates an example in which the power storage device 8203 is provided in the indoor unit 8200. The device 8203 may be provided in an outdoor unit 8204. Alternatively, the indoor unit 8200 and the outdoor unit The power storage device 8203 may be provided in both the power supply and the power source 8204. The power storage device 8203 can receive power from a commercial power source or can use the power stored in the power storage device 8203. In particular, both the indoor unit 8200 and the outdoor unit 8204 are provided with a power storage device 82 If 03 is installed, when power cannot be supplied from the commercial power source due to a power outage, etc. In addition, by using the power storage device 8203 of one embodiment of the present invention as an uninterruptible power supply, The conditioner can be used.

[0180] In Figure 26, a separate type air conditioner consisting of an indoor unit and an outdoor unit is shown. As an example, it is an all-in-one air conditioner that has the functions of both the indoor unit and the outdoor unit in a single housing. The power storage device according to one embodiment of the present invention can also be used in the conditioner.

[0181] In FIG. 26, an electric refrigerator-freezer 8300 includes a power storage device 8304 of one embodiment of the present invention. Specifically, an electric refrigerator-freezer 8300 includes a housing 8301, a refrigerator It has a storage compartment door 8302, a freezer compartment door 8303, a power storage device 8304, and the like. An electric device 8304 is provided inside the housing 8301. The electric refrigerator-freezer 8300 includes: The power can be supplied from a commercial power source, or the power stored in the power storage device 8304 can be used. Therefore, when power cannot be supplied from the commercial power source due to a power outage, etc. However, by using the power storage device 8304 of one embodiment of the present invention as an uninterruptible power supply, It will be possible to use the 8300 freezer refrigerator.

[0182] Among the above-mentioned electronic devices, high-frequency heating devices such as microwave ovens and electric rice cookers are Equipment requires high power for a short period of time, so it supplements the power that cannot be supplied by commercial power. By using a power storage device according to one embodiment of the present invention as an auxiliary power source for This prevents the commercial power breaker from tripping during use.

[0183] In addition, during times when electronic devices are not in use, especially when the total amount of power that can be supplied by the commercial power supplier is low, During times when the percentage of electricity actually used (called the electricity usage rate) is low, By storing power in the device, it is possible to prevent power usage rates from increasing outside of the above time periods. For example, in the case of the electric refrigerator-freezer 8300, when the temperature is low and the refrigerator compartment door 830 2. During the night when the freezer door 8303 is not opened or closed, the power storage device 8304 stores power. Then, as the temperature rises, the refrigerator door 8302 and the freezer door 8303 are opened and closed. By using the power storage device 8304 as an auxiliary power source during the daytime, the daytime power usage rate can be kept low.

[0184] In addition, when a power storage device is installed in a vehicle, it can be used in hybrid vehicles (HEVs), electric vehicles (EVs), Or realizing next-generation clean energy vehicles such as plug-in hybrid vehicles (PHEVs) can.

[0185] 27A and 27B show examples of vehicles using one embodiment of the present invention. 400 is an electric vehicle that uses an electric motor as a power source for running; or A hybrid vehicle that can select between an electric motor and an engine as a power source for driving. By using one aspect of the present invention, a vehicle with a long driving range can be realized. The automobile 8400 also has a power storage device. The power storage device can be used to power an electric motor. In addition to driving the headlights 8401 and room lights (not shown), can supply power to

[0186] In addition, the power storage device may be used for displaying the speedometer, tachometer, etc. of the automobile 8400. The power storage device can supply power to the navigation system of the automobile 8400. The present invention can provide power to semiconductor devices such as mobile terminals.

[0187] The automobile 8500 shown in FIG. 27B is a power storage device of the automobile 8500. It can be charged by receiving power from an external charging facility using a contactless power supply system or other methods. FIG. 27(B) shows the charging of electricity from a ground-mounted charging device 8021 to a storage battery mounted on an automobile 8500. The figure shows a state in which the charging device is being charged via a cable 8022. The power supply method and connector standards are applied according to the specified method such as CHAdeMO (registered trademark) or Combo. The charging device 8021 may be a charging station installed in a commercial facility. It can also be a household power source. For example, plug-in technology allows for external power supply. This allows charging of the storage device installed in the car 8500. This can be achieved by converting AC power into DC power via a conversion device such as a converter.

[0188] Although not shown, a power receiving device is mounted on the vehicle and power is supplied contactlessly from a power transmitting device on the ground. In this case, a power transmission device is installed on the road or exterior wall. By incorporating this technology, charging can be carried out not only when the vehicle is stopped but also while the vehicle is moving. This method may be used to transmit and receive power between vehicles. A solar cell may be provided to charge the power storage device while the vehicle is stopped or running. The power can be supplied by an electromagnetic induction method or a magnetic resonance method.

[0189] According to one embodiment of the present invention, the cycle characteristics of a power storage device can be improved, and the reliability can be improved. Furthermore, according to one embodiment of the present invention, the characteristics of the power storage device can be improved. Therefore, the size and weight of the power storage device itself can be reduced. This contributes to reducing the vehicle's weight, thereby improving the vehicle's cruising range. The power storage device can also be used as a power supply source for other purposes than vehicles. It is possible to avoid using commercial power during peak hours.

[0190] This embodiment mode can be implemented in appropriate combination with other embodiment modes. [Explanation of symbols]

[0191] 100 Electricity storage unit 101 Positive electrode 102 Negative electrode 103 Separator 104 Positive lead 105 Negative lead 106 Electrolyte 107 Exterior body 115 Sealing layer 118 Joint 119 entrance 150 Electricity storage unit 201 Bonding Die 202 Bonding Die 203 Protrusion 210 Connection Area 220 curved section 1700 curved surface 1701 Plane 1702 Curve 1703 Radius of curvature 1704 Center of curvature 1800 Center of curvature 1801 Film 1802 radius of curvature 1803 Film 1804 radius of curvature 1805 Battery materials 6003 Cathode active material 6004 Conductive additives 6005 Binder 6103 Negative electrode active material 6105 Binder 7100 Portable display devices 7101 Housing 7102 Display section 7103 Operation button 7104 Energy storage devices 7200 Personal Digital Assistant 7201 Case 7202 Display section 7203 Band 7204 Buckle 7205 Operation button 7206 Input / output terminal 7207 Icon 7300 display device 7304 Display section 7400 mobile phone 7401 Housing 7402 Display section 7403 Operation button 7404 External connection port 7405 Speaker 7406 Microphone 7407 Electricity storage devices 8000 display device 8001 Case 8002 Display section 8003 Speaker section 8004 Electricity storage devices 8021 Charging device 8022 cable 8100 Lighting equipment 8101 Housing 8102 Light source 8103 Energy storage devices 8104 Ceiling 8105 Side wall 8106 beds 8107 Window 8200 indoor unit 8201 Housing 8202 Ventilation outlet 8203 Energy storage devices 8204 Outdoor unit 8300 Electric refrigerator-freezer 8301 Housing 8302 Refrigerator door 8303 Freezer door 8304 Energy storage devices 8400 Automobiles 8401 Headlight 8500 cars 9600 tablet device 9625 Switch 9626 Switch 9627 Power Switch 9628 Operation Switch 9629 Ingredients 9630 chassis 9631 Display section 9633 Solar Cells 9634 Charge / Discharge Control Circuit 9635 Energy storage devices 9636 DC / DC Converter 9637 Converter 9638 Operation key 9639 Button 9640 Moving parts 101a Positive electrode current collector 101b Positive electrode active material layer 102a Negative electrode current collector 102b Negative electrode active material layer 150A power storage unit 150B Energy storage body 150C power storage body 200A power storage unit 200B Energy storage body 200C power storage body 200D electricity storage unit 200E Energy storage body 200F electricity storage body 200G power storage 200H electricity storage body 9630a housing 9630b housing 9631a Display section 9631b Display section 9632a area 9632b area

Claims

1. A power storage unit having a negative electrode, a positive electrode, a separator, and an outer casing, the negative electrode, the positive electrode, and the separator are each disposed within the exterior body; The exterior body has a joint on an outer periphery, The exterior body has continuous curved projections and recesses, the projections and recesses have regions that overlap positions where the power storage unit bends in a cross-sectional view, The electric storage unit is characterized in that the pitch of the projections and recesses is equal to or less than one-tenth of the linear vertical distance of the area surrounded by the joint.

2. In claim 1, The electricity storage unit characterized in that the exterior body has a laminate of a metal film and a thermoplastic film.

3. In claim 1 or claim 2, A storage battery characterized in that the height difference of the unevenness is five times or more the thickness of the exterior body.

Images