Power storage device

Abstract

To improve the flexibility of a power storage device, or to provide a high-capacity power storage device. The battery includes a positive electrode, a negative electrode, an outer casing, and an electrolyte. The positive electrode includes a positive electrode current collector and a negative electrode. The negative electrode has a positive electrode active material layer in contact with the negative electrode current collector, and a negative electrode has a negative electrode active material layer in contact with the negative electrode current collector. a negative electrode active material layer, the positive electrode active material layer and the negative electrode active material layer being overlapped with each other, The outer periphery of the negative electrode active material layer and the negative electrode active material layer is a closed curve, and the outer casing has a film. The inner periphery of the thermocompression bonding region is a closed curve, and the electrolyte, the positive electrode active material layer, and and the negative electrode active material layer is located in a region surrounded by the thermocompression bonded region, thereby providing an electricity storage device.

Description

[Technical Field]

[0001] One embodiment of the present invention relates to a power storage device and an electronic device.

[0002] Note that one embodiment of the present invention is not limited to the above technical fields. One aspect relates to a process, a machine, a method of manufacture. It relates to the composition of matter. More specifically, the technical field of one embodiment of the present invention disclosed in this specification is a semiconductor device, a display device, device, light emitting device, power storage device, storage device, driving method thereof, or manufacturing method thereof, for example. It can be mentioned as follows.

[0003] In this specification, the term "electronic device" refers to any device that is driven by electricity, and includes electro-optical devices. All of the above equipment, information terminal devices, etc. are electronic devices. In this case, the definition of built-in is that it is built in so that it cannot be removed and replaced. Needless to say, things that can be freely removed, such as battery packs, are also called built-in. . [Background technology]

[0004] In recent years, various types of energy storage devices such as lithium-ion secondary batteries, lithium-ion capacitors, and air batteries have become available. In particular, lithium-ion batteries, which have high output and high energy density, are being developed. Secondary batteries are used in mobile phones, smartphones, laptop computers and other portable information terminals, Electronic devices such as music players and digital cameras, medical equipment, and hybrid vehicles (HEV) ), electric vehicle (EV), fuel cell vehicle, or plug-in hybrid vehicle (PHEV) ) and other next-generation clean energy vehicles, along with the development of the semiconductor industry, demand is rapidly increasing. As a source of rechargeable energy, it has become indispensable in today's information society. are.

[0005] On the other hand, there has been active development of wearable devices that users wear on their bodies. For the user's comfort, the wearable device has a curved shape. Many of these wearable devices are flexible. To achieve this, flexible and bendable power storage devices are being developed.

[0006] For example, Patent Document 1 discloses a sheet-shaped electricity storage device that can be bent in at least one axial direction. and an electronic device equipped with the power storage device. The present invention discloses a secondary battery having a rechargeable battery and a wrist-worn electronic device having the secondary battery. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-211262 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-38868 Summary of the Invention [Problem to be solved by the invention]

[0008] Improved flexibility of power storage devices to accommodate the diversification of functions and shapes of wearable devices In addition, high-capacity batteries are required to reduce the frequency of charging wearable devices. There is a need to develop large-capacity energy storage devices.

[0009] Therefore, an object of one embodiment of the present invention is to improve the flexibility of a power storage device. An object of one embodiment of the present invention is to provide a power storage device that can be bent regardless of the direction. Another object of one embodiment of the present invention is to provide a high-capacity power storage device. An object of one embodiment is to provide a highly reliable power storage device.

[0010] Another object of one embodiment of the present invention is to provide a flexible electronic device. An object of one embodiment of the present invention is to provide an electronic device having a curved portion.

[0011] Another embodiment of the present invention is a novel electrode, a novel power storage device, a novel electronic device, or the like. The objective of this study is to provide the following: It is to be noted that one embodiment of the present invention does not necessarily solve all of these problems. Problems other than these will be obvious from the description, drawings, claims, etc. It is not possible to extract other issues from the description, drawings, claims, etc. It is possible to do this. [Means for solving the problem]

[0012] One embodiment of the present invention is a battery including a positive electrode, a negative electrode, an outer casing, and an electrolyte. and a positive electrode active material layer in contact with the positive electrode current collector, and the negative electrode has a negative electrode current collector and a negative electrode active material layer in contact with the negative electrode current collector. The positive electrode active material layer and the negative electrode active material layer are overlapped with each other, and the positive electrode active material layer is in contact with the negative electrode active material layer. The outer periphery of the electrode active material layer and the negative electrode active material layer is a closed curve, the outer casing has a film, The housing has a thermocompression region, the inner periphery of which is a closed curve, and is provided with an electrolyte, a positive electrode active material, and a The layer and the negative electrode active material layer are located in a region surrounded by the thermocompression bonded region, and are an electricity storage device.

[0013] In one embodiment of the present invention, in the above structure, the outer periphery of the positive electrode active material layer and the negative electrode active material layer is It is more preferable that the inner periphery of the thermocompression bonding region is approximately circular.

[0014] Further, one embodiment of the present invention is a battery including a positive electrode, a negative electrode, an outer casing, and an electrolyte. The negative electrode has a negative electrode current collector and a positive electrode active material layer in contact with the positive electrode current collector. and a negative electrode active material layer in contact with the positive electrode active material layer and the negative electrode active material layer overlap each other. The outer periphery of the positive electrode active material layer and the negative electrode active material layer is a closed curve, and the outer casing has a film. The exterior body has a first thermocompression bonding area and a second thermocompression bonding area, and the first thermocompression bonding area is The first thermocompression bonding area is surrounded by a second thermocompression bonding area, and the periphery of the first thermocompression bonding area is a closed curve. The inner periphery of the first thermocompression bonding region is a closed curve, and the exterior body has an opening in the region surrounded by the first thermocompression bonding region. The electrolyte, the positive electrode active material layer, and the negative electrode active material layer are bonded to each other in a first thermocompression region and a second thermocompression region. The positive electrode current collector has a portion that protrudes into the opening, and the negative electrode current collector has a portion that protrudes into the opening. The power storage device has a protruding portion.

[0015] In one embodiment of the present invention, in the above structure, the outer periphery of the positive electrode active material layer and the negative electrode active material layer is It is more preferable that the inner periphery of the second thermocompression bonding region is approximately circular.

[0016] Another aspect of the present invention is a battery comprising a positive electrode, a negative electrode, a positive electrode lead, a negative electrode lead, an outer casing, and a battery. the positive electrode has a positive electrode current collector and a positive electrode active material layer in contact with the positive electrode current collector; The negative electrode has a negative electrode current collector and a negative electrode active material layer in contact with the negative electrode current collector, and a positive electrode active material layer and The negative electrode active material layers overlap each other, and the outer peripheries of the positive electrode active material layer and the negative electrode active material layer are in the form of a closed curve. The exterior body has a film, and the exterior body has a first thermocompression bonding area and a second thermocompression bonding area. The first thermocompression region is surrounded by the second thermocompression region, and the periphery of the first thermocompression region is closed. The inner periphery of the second thermocompression region is a closed curve, and the outer casing is a closed curve of the first thermocompression region. The electrolyte, the positive electrode active material layer, and the negative electrode active material layer are formed by a first thermal The positive electrode lead is located in the region between the first thermocompression region and the second thermocompression region. The positive electrode lead is electrically connected to the positive electrode current collector in the region between the second thermocompression bonded region. The negative electrode lead has a portion projecting into the opening, and the negative electrode lead has a first thermocompression bonding region and a second thermocompression bonding region. The negative electrode lead is electrically connected to the negative electrode current collector in the region between the negative electrode current collector and the negative electrode lead. The power storage device has the following features.

[0017] In one embodiment of the present invention, in the above structure, the outer periphery of the positive electrode active material layer and the negative electrode active material layer is It is more preferable that the inner periphery of the second thermocompression bonding region is approximately circular.

[0018] In addition, one aspect of the present invention is a film having a storage layer having a convex portion or a concave portion in each of the above-mentioned configurations. In addition, in each of the above structures, one embodiment of the present invention is a method for manufacturing a semiconductor device, or the outer periphery of the positive electrode active material layer or the negative electrode active material layer has a shape similar to the outer periphery of the positive electrode active material layer or the negative electrode active material layer. be.

[0019] In one embodiment of the present invention, in any of the above structures, the power storage device preferably has flexibility. stomach.

[0020] Another embodiment of the present invention is a power storage device having any of the above structures and an electronic device including a flexible housing. Another embodiment of the present invention is a power storage device including a power storage device having any of the above structures and a housing having a curved portion. It is an electronic device. [Effects of the Invention]

[0021] According to one embodiment of the present invention, the flexibility of a power storage device can be improved. According to this embodiment, it is possible to provide an electricity storage device that can be bent regardless of the direction. According to one embodiment of the present invention, a high-capacity power storage device can be provided. In this manner, a highly reliable electricity storage device can be provided.

[0022] Furthermore, one embodiment of the present invention can provide a flexible electronic device. One aspect of the present invention is to provide an electronic device having a curved portion.

[0023] Furthermore, a novel electrode, a novel power storage device, or a novel electronic device can be provided. The description of these effects does not preclude the existence of other effects. The method does not necessarily have to have all of these effects. In addition, effects other than these may include: It is self-evident from the description, drawings, claims, etc. Other effects can be extracted from the claims and other descriptions. [Brief explanation of the drawings]

[0024] [Figure 1] 1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 2] 1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 3] 1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 4]1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 5] 1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 6] 1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 7] 1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 8] 1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 9] 1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 10] 1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 11] 1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 12] 1A and 1B illustrate a power storage device of one embodiment of the present invention. [Figure 13] 1A to 1C illustrate a method for manufacturing a power storage device of one embodiment of the present invention. [Figure 14] 1A to 1C illustrate a method for manufacturing a power storage device of one embodiment of the present invention. [Figure 15] 1A to 1C illustrate a method for manufacturing a power storage device of one embodiment of the present invention. [Figure 16] 1A to 1C illustrate a method for manufacturing a power storage device of one embodiment of the present invention. [Figure 17] 1A to 1C illustrate a method for manufacturing a power storage device of one embodiment of the present invention. [Figure 18] 1A to 1C illustrate a method for manufacturing a power storage device of one embodiment of the present invention. [Figure 19] 1A to 1C illustrate a method for manufacturing a power storage device of one embodiment of the present invention. [Figure 20] 1A to 1C illustrate a method for manufacturing a power storage device of one embodiment of the present invention. [Figure 21] 1A to 1C illustrate a method for manufacturing a power storage device of one embodiment of the present invention. [Figure 22] 1A to 1C illustrate active materials that can be used in a power storage device. [Figure 23] 10A to 10C are diagrams illustrating a conductive additive and the like. [Figure 24] 10A to 10C are diagrams illustrating a conductive additive and the like. [Figure 25] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Figure 26] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Figure 27] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Figure 28] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Figure 29] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Figure 30] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Figure 31] 1A to 1C illustrate electronic devices of one embodiment of the present invention. [Figure 32] 1A to 1C illustrate electronic devices of one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0025] 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.

[0026] In this specification, "connection" means connection via "something that has some kind of electrical effect." Here, "something that has some kind of electrical effect" means the There are no particular limitations as long as it is possible to send and receive electrical signals.

[0027] The words "film" and "layer" may be used interchangeably depending on the situation. For example, the term "conductive layer" can be replaced with "conductive film." ". Alternatively, for example, the term "insulating film" may be used. It may be possible to change the term to "insulating layer."

[0028] The position, size, range, etc. of each component shown in the drawings are not necessarily the actual size for ease of understanding. Therefore, the disclosed invention may not necessarily represent the position, size, range, etc. Furthermore, the present invention is not limited to the position, size, range, etc. disclosed in the drawings, etc.

[0029] In this specification, ordinal numbers such as "first," "second," and "third" are used to indicate the composition of the elements. It should be noted that the numbers are added to avoid confusion and are not intended to limit the number.

[0030] In this specification, "parallel" means that two straight lines are arranged at an angle of -10° or more and 10° or less. Therefore, it includes the case of -5° or more and 5° or less. "Line" refers to the state in which two straight lines are arranged at an angle between -30° and 30°. "Perpendicular" means that two straight lines are arranged at an angle of 80° or more and 100° or less. Therefore, it also includes the case where the angle is between 85° and 95°. This refers to a state in which two straight lines are arranged at an angle of 60° or more and 120° or less.

[0031] (Embodiment 1) In this embodiment, a power storage device of one embodiment of the present invention will be described with reference to FIGS. 1 to 9. .

[0032] [1. Basic configuration] First, a basic configuration of an electricity storage device 100 will be described with reference to FIGS. 1 to 3. 1(A) is a front view of the power storage device 100, FIG. 1(B) is a side view of the power storage device 100, and FIG. FIG. 1(C) is a front view of the positive electrode 111 of the power storage device 100, and FIG. 1(D) is a front view of the positive electrode 111 of the power storage device 100. 1 shows a front view of the negative electrode 115.

[0033] 2A is a cross-sectional view of the power storage device 100 taken along the dashed line AB in FIG. 1A. 2B shows a cross-sectional view taken along the dashed line CD. A cross-sectional view of the negative electrode 11 shown in FIG. A cross-sectional view of 5 taken along the dashed line GH is shown in FIG. 2(D).

[0034] As shown in FIGS. 1A and 1B, the energy storage device 100 includes an exterior body 110 and a terminal electrode The exterior body 110 has a positive electrode lead 141 and a negative electrode lead 145. The circular film 109a and the circular film 109b are stacked and heated at the periphery. The positive electrode lead 141 and the negative electrode lead 145 each have a bonding area 120. are enclosed in the exterior body 110. In addition, the positive electrode lead 141 and the negative electrode lead 145 are The other part of the positive electrode lead 141 and the negative electrode lead 142 extend outside the package 110. The portions of 145 that overlap with the respective heat-bonded regions 120 are made of polypropylene (PP) or the like. A sealing layer 121 made of a thermoplastic resin is provided, and the film 109a and the film 109b are the adhesion between each film and the positive electrode lead 141, and the adhesion between each film The adhesion between the negative electrode lead 145 and the negative electrode lead 146 is improved.

[0035] The power storage device 100 of one embodiment of the present invention includes the film 109a and the film 109b. The exterior body 110 is formed using a flexible film. The flexibility of the power storage device 100 can be improved.

[0036] The film is a metal foil laminate film, which is made by laminating a plastic film on a metal foil. The metal foil laminate film can be sealed by thermocompression bonding. This is preferable because it has the advantages of being highly flexible in shape, lightweight, and flexible. The metal foil materials used in metal foil laminate films include aluminum, stainless steel, copper, etc. tin, nickel steel, etc. can be used. Materials such as polyethylene terephthalate, nylon, polyethylene, and PP can be used. This can be done.

[0037] In this specification, a laminate refers to a thin material such as a metal foil or a plastic film. This refers to a processing method in which materials are pasted together and laminated.

[0038] In addition, the film contains metal foil, organic materials (organic resins, fibers, etc.) and inorganic materials (ceramics, etc.). etc.), hybrid material films including carbon-containing inorganic films (carbon films, graphite film, etc.) or a laminated film consisting of a plurality of these films. A laminate of films may also be used.

[0039] As described above, the energy storage device 100 has the thermocompression bonded region 120 on the periphery of the exterior body 110. If the inner periphery of the thermocompression bonding region 120 is a closed curved line as shown in FIG. The inner periphery of the thermocompression bonding area 120 is preferably A circular or approximately circular shape is more preferable, the reason for which will be explained with reference to FIG.

[0040] In this specification, a closed curve refers to a continuous curve whose both ends are coincident. A closed curve is a shape that is made up of a series of curved sections with different curvatures, such as an ellipse, a circle, or a circle. do.

[0041] When the shape of the power storage device 100 is changed by applying an external force, the exterior body 1 Of these, some parts are under compressive stress and others are under tensile stress. The stress may cause the exterior body to distort, resulting in partial deformation or destruction of the exterior body 110. be.

[0042] Strain is the deformation that indicates the displacement of a material point within an object relative to the reference (initial) length of the object. is a measure of.

[0043] Figure 3 shows various shapes of energy storage devices and the direction of stress applied to the exterior body when the energy storage device is bent. The arrow 150 indicates the direction of the arrow. FIG. 3(A) shows a front view of the power storage device 100. FIG. 3(B) shows the direction of the arrow. ) shows a part of a power storage device in which the inner periphery of the thermocompression bonding region is polygonal. 1 shows a part of an electricity storage device in which an exterior body is formed by folding a single film.

[0044] As shown in FIG. 3B, the inner periphery of the thermocompression bonding region 120 of the exterior body 110 is polygonal. When this happens, a vertex 151 is generated. At this time, an external force is applied to bend the power storage device, and the vertex 151 is generated as shown by the arrow 15. When stress is applied in the direction indicated by 0, the stress tends to concentrate at the vertex 151 and its surrounding area. As a result, the exterior body 110 is subjected to stress concentration starting from the vertex 151 and its surrounding area. There is a risk that the battery may be damaged, causing the electrolyte solution contained in the exterior body 110 to leak.

[0045] Also, as shown in FIG. 3(C), by folding one piece of film at the folding portion 153, When forming a twisted outer casing, the apex where the inner periphery of the thermocompression bonding area 120 intersects with the folded portion 153 At this time, when the electricity storage device is bent and stress is applied in the direction indicated by arrow 150, Stress tends to concentrate at vertex 152 and its surrounding area. There is a possibility that damage will occur starting from the area where stress is concentrated, such as 52 or its surrounding area. The bent portion 153 is more likely to be damaged by bending than the thermocompression bonded region 120. Therefore, in the electricity storage device having such a structure, in order to prevent the bent portion 153 from being damaged, Orientation is restricted.

[0046] On the other hand, in the energy storage device 100 shown in FIG. 3(A), the inner periphery of the thermocompression bonded region is a closed curve. As a result, when the power storage device 100 is bent, the exterior body 110 Therefore, as shown by arrow 150, the direction of the stress can be determined. Therefore, the exterior body of the power storage device 100 is not easily damaged even when it is subjected to a strong force. In addition, the product does not have any bent portions that are easily damaged by bending. Therefore, the power storage device 100 can be bent regardless of the bending direction.

[0047] Furthermore, if the inner periphery of the thermocompression bonding area 120 is circular or approximately circular, stress will be concentrated at one point. This more reliably prevents damage to the exterior body 110 caused by bending the power storage device 100. It is possible.

[0048] As shown in FIGS. 2A and 2B, the electricity storage device 100 includes a film 109a and a filter 109b. The positive electrode 109 is sandwiched between the exterior body 110 made of the film 109b and surrounded by the thermocompression bonding area 120. 111, a negative electrode 115, a separator 107, and an electrolyte 108. The positive electrode 111 is a positive electrode collector. a positive electrode current collector 101 and a positive electrode active material layer 102 in contact with the positive electrode current collector 101; The negative electrode 115 is connected to the negative electrode current collector 105. The negative electrode active material layer 106 is in contact with the current collector 105, and the negative electrode lead 145 is connected to the negative electrode current collector 105. 05 (not shown). The positive electrode active material layer 102 and the negative electrode active material layer 106 are , overlapping each other with a separator 107 interposed therebetween.

[0049] As shown in FIG. 1(C) and FIG. 2(C), in the positive electrode 111, the positive electrode current collector 101 is A portion 101a that does not contact the positive electrode active material layer 102 and a portion 101b that contacts the positive electrode active material layer 102 The periphery of the portion 101b and the positive electrode active material layer 102 is a closed curve. 1a is a tab (hereinafter referred to as a positive electrode lead) for electrically connecting a positive electrode lead 141 to a positive electrode current collector 101. It can function as a polar tab.

[0050] As shown in FIG. 1(D) and FIG. 2(D), in the negative electrode 115, the negative electrode current collector 105 A portion 105a that does not contact the electrode active material layer 106 and a portion 105b that contacts the electrode active material layer 106 The outer periphery of the portion 105b and the negative electrode active material layer 106 is a closed curve. 5a is a tab (hereinafter referred to as negative electrode lead 145) for electrically connecting the negative electrode lead 145 to the negative electrode current collector 105. It can function as a polar tab.

[0051] In the power storage device 100, the positive electrode active material layer 102 does not overlap with the negative electrode active material layer 106. In the case where the negative electrode active material layer 106 has Therefore, the negative electrode active material layer 106 and the positive electrode active material layer 102 may be separated. The width of the opposing surfaces is preferably 2% or more and 10% or less, more preferably 3% or more and 7% or less. , the width of the surface of the positive electrode active material layer 102 facing the negative electrode active material layer 106 is larger than the width of the surface of the negative electrode active material layer 106 facing the positive electrode active material layer 102. As a result, the positive electrode active material layer 102 is reliably connected to the negative electrode active material layer 103 via the separator 107. The negative electrode active material layer 106 and the positive electrode active material layer 102 can overlap each other. In the case of the negative electrode active material layer 106, the diameter of the negative electrode active material layer 106 is preferably 2% or more and 10% or less, more preferably 10% or less. Preferably, the diameter is greater than the diameter of the positive electrode active material layer 102 by 3% to 7%.

[0052] In the electricity storage device 100, as described above, the positive electrode active material layer 102 of the positive electrode current collector 101 is in contact with the positive electrode active material layer 102. The outer periphery of the positive electrode active material layer 102 and the portion 101b formed by the negative electrode current collector 101 are formed in a closed curve. The portion 105b of the negative electrode active material layer 106 in contact with the negative electrode active material layer 106 and the outer periphery of the negative electrode active material layer 106 are formed by a closed curve. The exterior body 110 is formed in a shape such that it does not have any corners or straight lines that are likely to cause damage. This allows the exterior body 110 to be configured to be less likely to be damaged when the power storage device 100 is bent. .

[0053] The portion 101b in contact with the positive electrode active material layer 102, the outer periphery of the positive electrode active material layer 102, and the negative electrode active material layer 103 are The portion 105b in contact with the electrode active material layer 106 and the outer periphery of the negative electrode active material layer 106 are circular or approximately If the shape is circular, the area sandwiched between the exterior body 110 and surrounded by the thermocompression bonding area 120 can be efficiently utilized. This is possible and preferable.

[0054] In the electricity storage device 100, the positive electrode active material layer 102 is in contact with both surfaces of the positive electrode current collector 101. a cathode 111 in contact with one surface of the anode current collector 105 and a cathode in which the anode active material layer 106 is in contact with one surface of the anode current collector 105; However, one embodiment of the present invention is not limited to this. Even if a positive electrode 111 in which the positive electrode active material layer 102 is in contact with one surface is used, the negative electrode current collector 105 The negative electrode 115 in contact with the negative electrode active material layer 106 may be used.

[0055] As either the positive electrode 111 or the negative electrode 115, or both, active materials are applied to both sides of the current collector. The use of electrodes in contact with the layers can increase the capacity per volume of the energy storage device 100. This is possible and preferable.

[0056] In addition, one of the positive electrode 111 and the negative electrode 115, or both of them, is If an electrode having an active material layer in contact with the surface is used, the capacity may decrease when the power storage device 100 is bent. This is preferable because it can prevent deterioration of cycle characteristics and the like.

[0057] For example, as shown in FIG. 2(A), the negative electrode current collector 105 and the negative electrode current collector 106 are in contact with each other at the contact surface 125. In this way, when the current collector has a surface where the current collectors come into contact with each other, This allows the electric storage device 100 to slide on the contact surface. Therefore, by bending the energy storage device 100, the stress applied to the electrodes can be released. The current collector is prevented from being broken, the active material layer is prevented from being damaged, and the capacity of the electricity storage device 100 is prevented from decreasing. This can prevent deterioration of the battery's performance and cycle characteristics.

[0058] In the electricity storage device 100, the positive electrode 111, the negative electrode 115, and the separator 10 The number, size, and stacking order of 7 are not limited to the above method. A positive electrode 111 having a positive electrode current collector 101 and a positive electrode active material layer 102, a negative electrode current collector 105 and a negative Another example of a laminate having a negative electrode 115 having an electrode active material layer 106 and a separator 107 is shown below. We will explain about this.

[0059] As shown in FIG. 4(A), in the energy storage device 100, the laminate has a tapered shape. In this way, by bending the power storage device 100, the corners of the laminated body may be in contact with the exterior body 1. This can reduce the impact on the exterior body 110, making the exterior body 110 less likely to be damaged. Furthermore, the area sandwiched between the exterior bodies 110 and surrounded by the thermocompression bonded area is used efficiently, and the laminate can be placed.

[0060] The laminate shown in FIG. 4(A) includes, for example, a positive electrode 111, a negative electrode 115, and a separator 107. After lamination, the laminate is cut into a tapered shape using a cutter or laser cutter. Alternatively, the positive electrode 111, the negative electrode 115, and the separator 10 may be formed by 7 For each, use a cutter or laser cutter to create a tapered edge. The electrode 111, the negative electrode 115, and the separator 107 may be laminated to form the laminate. Alternatively, the edges of the positive electrode 111, the negative electrode 115, and the separator 107 may be tapered. The positive electrode 111, the negative electrode 115, and the separator 116 may be different in size. By stacking the plates 107, a tapered laminate may be formed.

[0061] 4(B), the laminate may have a positive electrode active material on both sides of the positive electrode current collector 101. Two positive electrodes 111 are in contact with the negative electrode active material layer 102, and one surface of the negative electrode current collector 105 is provided with the negative electrode active material layer 10 Two negative electrodes 115 in contact with the negative electrode active material layer 106 on both sides of the negative electrode current collector 105 are provided. As shown in FIG. 4(B), the active material layer is provided on both sides of the current collector. This allows the capacity per unit volume of the power storage device 100 to be increased.

[0062] 4(B), the separator 107 is formed in a bag shape and the positive electrode 111 is wrapped around the separator 107. This may cause the positive electrode 111 and the negative electrode 115 to come into contact with each other, resulting in a short circuit. This can be reliably prevented.

[0063] For example, as shown in FIG. 4(C), a gel-like electrolyte solution 108a is used as the electrolyte solution 108. A set of a positive electrode 111, a negative electrode 115 and a separator 107 is stuck together with an electrolyte 108. With this configuration, when the power storage device 100 is bent, the battery reaction can be prevented. This can prevent the positive electrode 111 and the negative electrode 115 from slipping.

[0064] In addition, the surfaces of the positive electrodes 111 that do not have the positive electrode active material and the surfaces of the negative electrodes 115 that do not have the negative electrode active material are This allows for a large number of metal-to-metal contact surfaces, i.e., surfaces that are not in contact with each other. The sliding contact surface more reliably releases the stress applied to the electrodes when bending the electricity storage device 100. This is preferable.

[0065] Therefore, it is possible to suppress deterioration of the power storage device 100. Therefore, the power storage device 100 can be made small.

[0066] In the energy storage device 100 shown in FIG. 1, the outer periphery of the thermocompression bonded region 120 is circular. One embodiment of the present invention is not limited to this. For example, as shown in FIG. 5(A), The outer periphery of the thermocompression bonding area 12 may be polygonal. The outer periphery of the 0 may have a protrusion.

[0067] In the energy storage device 100 shown in FIGS. 1 and 2, the width of the thermocompression bonded region 120 is uniform. The width of the thermocompression bonding area 120 may be uniform, but may vary in width depending on the area. For example, as shown in FIG. 5(C), the thermocompression bonding region 120 may be different from the positive electrode lead. In the area where the negative electrode lead 141 and the negative electrode lead 145 overlap, the width of the thermocompression bonding area 120 is widened. This allows the positive electrode lead 141 and the negative electrode lead 145 to be more securely wrapped around the exterior. It is preferable that the body 110 can be fixed thereto.

[0068] The following describes modified examples of the power storage device 100. In the modified examples, For details of the configuration, symbols, and drawings, please refer to the description of the basic configuration.

[0069] [2. Variation 1] A first modification of the power storage device 100 will be described with reference to FIG. 6. In FIG. 6(A), the power storage device 100 6(A) and 6(B) are cross-sectional views of the power storage device 100 taken along the dashed line AB in FIG. The diagram is shown in Figure 6(B).

[0070] As shown in FIGS. 6(A) and 6(B), in the power storage device 100, the film constituting the exterior body 110 The rooms 109a and 109b may have recesses 131 and protrusions 132. The convex portions can be formed by embossing or the like. By performing the embossing process, recesses or protrusions are formed on the exterior body 110. When the heat sink is formed, the surface area of ​​the exterior body 110 that is exposed to the outside air increases, and therefore, the heat sink has excellent heat dissipation properties. The electrical device 100 may be:

[0071] Furthermore, by forming a recess or a protrusion on the exterior body 110, it is possible to Even if strain occurs in the exterior body 110 due to the application of force, damage or the like can be prevented. can be done.

[0072] In addition, by forming recesses or protrusions on the exterior body 110 by embossing or the like, the exterior body 1 Increasing the creepage distance of 10 reduces the compressive and tensile stresses per unit length. Therefore, the reliability of the power storage device 100 can be improved.

[0073] In this way, when the exterior body 110 is provided with irregularities, the film 1 This can relieve strain caused by stress being applied to 09a and 109b. Therefore, the film 109a and the film 109b are prevented from being deformed or destroyed. This can prevent the following.

[0074] The recesses 131 and the protrusions 132 of the films 109a and 109b are If the layer has a shape similar to the positive electrode active material layer 102 or the negative electrode active material layer 106, the strain can be reduced. This is preferable as it makes it easier to alleviate the pain.

[0075] More specifically, the inner periphery of the recess 131 or the protrusion 132 is in contact with the positive electrode active material layer 102 or the negative electrode active material layer 103. It is preferable that the recess 131 has a shape similar to the outer periphery of the electrode active material layer 106. The outer periphery of the protrusion 132 is similar to the outer periphery of the positive electrode active material layer 102 or the negative electrode active material layer 106. It is preferable that the shape is the same as that of the conventional ferroelectric liquid crystal display.

[0076] In the basic configuration and the first modified example, the positive electrode lead 141 and the negative electrode lead 145 are close to each other. 7, an example in which the semiconductor device is arranged in the following order is shown, but one embodiment of the present invention is not limited to this. The positive electrode lead 141 and the negative electrode lead 145 may be disposed far from each other. The positive electrode lead 141 and the negative electrode lead 145 do not have to be arranged parallel to each other.

[0077] In the basic configuration and the first modified example, the positive electrode lead 141 and the negative electrode lead 142 are terminal electrodes. 145 has been shown as an example in which it protrudes from the periphery of the exterior body 110, but in the following modified examples 2 and 3, As shown in FIG. 1, the positive electrode lead 141 and the negative electrode lead 145 protrude from the opening of the exterior body 110. It may also be possible to use the following.

[0078] [3. Variation 2] A second modification of the power storage device 100 will be described with reference to FIG. 8. In FIG. 8(A), the power storage device 100 8(A) and 8(B) are cross-sectional views of the power storage device 100 taken along the dashed line AB in FIG. The diagram is shown in FIG. 8(B).

[0079] As shown in Figures 8(A) and 8(B), the exterior body 110 may have an opening. 0 is a film having two circular films with a circular opening in the center, film 109a and film The film 109a and the film 109b are then placed on top of each other, and the periphery of the openings in the film 109a and the film 109b is heated. This forms the thermocompression bonded region 120a, and the film 109a and the film 109b The thermocompression bonded region 120b is formed by heating the periphery of the substrate.

[0080] In the energy storage device 100 shown in this modification, the outer periphery of the thermocompression bonded region 120a is a closed curve. If the inner periphery of the region 120b is a closed curve, the exterior body 1 can be easily opened by bending the power storage device 100. This is preferable because it can prevent damage to the thermocompression bonding area 120a. If the inner periphery of the thermocompression bonding area 120b is substantially circular or circular, the exterior body 110 will not be damaged. This is more preferable because it can more reliably prevent this.

[0081] The positive electrode 111 includes a positive electrode current collector 101, a positive electrode active material layer 102 in contact with the positive electrode current collector 101, and The negative electrode 115 has a negative electrode current collector 105 and an opening. The cathode active material layer 102 and the anode active material layer 106 are in contact with each other and have an opening. The positive electrode active material layer 106 and the positive electrode active material layer 107 are overlapped with each other via a separator 107. The material layer 102, the negative electrode active material layer 106, and the separator 107 are formed by a film 109a and a film The film 109b is sandwiched between the thermocompression bonding area 120a and the thermocompression bonding area 120b. Located in the area.

[0082] The portion of the positive electrode current collector 101 that is not in contact with the positive electrode active material layer 102 is near the center of the positive electrode 111. In addition, the portion of the negative electrode current collector 105 that is not in contact with the negative electrode active material layer 106 is located at the negative electrode. Located near the center of Pole 115.

[0083] The portion of the positive electrode current collector 101 that is not in contact with the positive electrode active material layer 102 and the portion of the negative electrode current collector 105 that is not in contact with the negative electrode active material layer 102 are A part of each of the portions not in contact with the material layer 106 is surrounded by an exterior body 110, and the other portions are It extends outside the exterior body 110.

[0084] The two positive electrode current collectors 101 are stacked and ultrasonically bonded to form a laminate. The four negative electrode current collectors 105 are stacked and ultrasonically bonded to form a laminate. With this configuration, the terminal electrodes can be formed without using lead electrodes.

[0085] The electric storage device 100 shown in this modification has a terminal at the center, and the center is fixed by thermocompression bonding. This allows the amount of deformation near the terminal electrodes to be controlled when an external force is applied to bend the energy storage device. This can prevent the terminal electrodes from being damaged. Furthermore, no lead electrodes are used, which reduces the number of parts.

[0086] As shown in FIG. 8(C), the power storage device 100 shown in this modification is a device in which a plurality of devices are stacked. By connecting the terminal electrodes of each of the power storage devices 100 to the wiring 156 or the wiring 157, , and can be used as a cylindrical electricity storage device.

[0087] In addition, by increasing the number of current collectors used and increasing the thickness of the laminate formed as the terminal electrode, When this configuration is used, the film 109a and the film 109b are brought into close contact with the current collector. Therefore, it becomes difficult to bond the positive electrode current collector 101 to the positive electrode active material layer 102. By providing a sealing layer on a portion of the negative electrode current collector 105 that is not in contact with the negative electrode active material layer 106, Adhesion between film 109a and film 109b, and adhesion between each film and the terminal electrodes Adhesion may be improved.

[0088] Furthermore, the power storage device 100 having an opening may have a structure like that of Modification 3 shown in FIG.

[0089] [4. Variation 3] The power storage device 100 shown in FIG. 9 has an exterior body 110 with an opening. The battery 10 includes a positive electrode lead 141, a negative electrode lead 145, and a sealing layer 121.

[0090] A portion of each of the positive electrode lead 141 and the negative electrode lead 145 is enclosed by the exterior body 110 . The other parts of the positive electrode lead 141 and the negative electrode lead 145 are attached to the exterior body 110. The positive electrode lead 141 extends from the outer casing 110 and protrudes into the opening of the outer casing 110. The enclosed area is connected to the positive electrode 111, and the negative electrode lead 145 is connected to the negative electrode 115. will be done.

[0091] The positive electrode lead 141 and the negative electrode lead 145 are provided with a sealing layer 121, so that the outer casing The adhesiveness between the films constituting the positive electrode lead 110 can be improved. The sealing layer 121 may not be provided on the negative electrode lead 41 and the negative electrode lead 145 .

[0092] The positions at which the positive electrode lead 141 and the negative electrode lead 145 protrude into the opening of the exterior body 110 are as follows: There is no particular limitation, and it may be close or far.

[0093] [5. Other Modifications] Next, other examples of the shape of the electricity storage device 100 will be introduced with reference to FIGS.

[0094] As described above, in the energy storage device 100, the outer peripheries of the positive electrode active material layer and the negative electrode active material layer are closed curves. It is preferable that the inner periphery of the thermocompression bonding region is in the form of a closed curve. In this example, the outer periphery of the material layer and the negative electrode active material layer is circular, and the inner periphery of the thermocompression bonding region is circular. However, the present embodiment is not limited to this. Also, the inner periphery of the thermocompression bonding area can be any shape as long as it is a closed curve. It doesn't matter if it's in this state.

[0095] For example, as shown in FIG. 10, the power storage device 100 includes an oval-shaped exterior body 110, an oval-shaped positive electrode a positive electrode 111 having an active material layer 102, a negative electrode 115 having an elliptical negative electrode active material layer 106, and an oval separator 107. Also, the outer casing 110 is thermocompression bonded. The inner periphery of the region 120 may be elliptical.

[0096] In some cases, the outer periphery of the positive electrode active material layer and the negative electrode active material layer may have a shape having a straight line portion. The inner periphery of the thermocompression bonding area may have a curved shape. For example, as shown in FIG. 11, the power storage device 100 includes a semicircular exterior body 110 and a semicircular center A positive electrode 111 having a positive electrode active material layer 102, and a negative electrode 11 having a semicircular negative electrode active material layer 106. 5 and a semicircular separator 107. The inner periphery of the thermocompression bonding region 120 may be semicircular.

[0097] As shown in FIG. 12, the power storage device 100 includes a rectangular exterior body 110 with rounded corners, a positive electrode 111 having a rectangular positive electrode active material layer 102 with rounded corners, and a negative electrode The negative electrode 115 has an active material layer 106, and the separator 107 has a rectangular shape with rounded corners. In addition, the inner periphery of the thermocompression bonding region 120 of the exterior body 110 may be a square with rounded corners. It may be a shape.

[0098] As shown in FIGS. 11 and 12, the positive electrode active material layer 102 and the negative electrode active material layer 106 are arranged in a straight line. Even if the shape has a curved portion, depending on the method of use of the energy storage device and the direction in which the energy storage device is bent, This makes it possible to make the exterior body 110 less susceptible to damage.

[0099] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0100] (Embodiment 2) In this embodiment, the power storage device 100 of one embodiment of the present invention will be described with reference to FIGS. An example of a manufacturing method will be described. As an example, the basic structure described in Embodiment 1 (FIG. 1) 2. A method for manufacturing the power storage device 100 will be described.

[0101] [1. Prepare the positive electrode and cover it with a separator] First, the positive electrode active material layer 102 is formed on both sides of the positive electrode current collector 101, and then processed into the shape of the positive electrode 111. Next, the positive electrode 111 is sandwiched between two separators 107 (FIG. 13(A)).

[0102] The outer peripheral portion of the separator 107 is then bonded to the outside of the positive electrode 111 to form a bag-shaped separator. The outer periphery of the separator 107 is bonded with an adhesive or the like. Alternatively, ultrasonic welding or heat fusion may be used.

[0103] In this embodiment, polypropylene is used as the separator 107. The outer periphery of the adhesive is bonded by heating. The bonded portion is shown as region 107a in FIG. 13(B). In this way, the positive electrode 111 can be covered with the separator 107. The layer 7 only needs to be formed to cover the positive electrode active material layer 102, and does not need to cover the entire positive electrode 111. None.

[0104] In FIG. 13(A), the positive electrode 111 is sandwiched between two separators 107. One embodiment is not limited to this. For example, a separator may be folded to form a positive electrode 111. may be sandwiched between them.

[0105] The outer peripheral portion of the separator 107 may be bonded intermittently or in a manner similar to that shown in FIG. 13(B). The adhesive may be applied in dots at regular intervals as shown in FIG.

[0106] The shape of the separator 107 is not limited to a bag shape. It is sufficient to prevent contact between the positive electrode 111 and the negative electrode 115 in the electricity storage device 100. For example, it may be in the form of a flat plate. When the positive electrode active material layer 102 is in contact with the positive electrode 111, the positive electrode 111 must be sandwiched between the separator 107. That's fine.

[0107] [2. Prepare the negative electrode] Next, the negative electrode active material layer 106 is formed on the negative electrode current collector 105 and processed into the shape of the negative electrode 115. (Figure 13(C)).

[0108] [3. Stacking the positive and negative electrodes] Next, the positive electrode 111 and the negative electrode 115 are laminated (FIG. 14(A)). Two positive electrodes 111 each having a positive electrode active material layer formed on both sides of a current collector were placed on one side of a negative electrode current collector. Four negative electrodes 115 each having a positive electrode active material layer formed thereon are stacked. The negative electrode active material layer 102 and the negative electrode active material layer 106 are arranged so as to overlap with each other via a separator 107. The negative electrodes 115 are arranged so that the surfaces on which the negative electrode active material layers 106 are not formed are in contact with each other.

[0109] [4. Connect the positive and negative leads] Next, the positive electrode tabs of the plurality of positive electrode current collectors 101 and the positive electrode lead 141 having the sealing layer 121 are , and ultrasonic waves are applied while pressure is applied to create an electrical connection (ultrasonic welding).

[0110] The lead electrodes may crack or break due to stress caused by external force applied after the energy storage device is manufactured. Therefore, when ultrasonically welding the positive electrode lead 141, a bonding The positive electrode tab may be sandwiched between wires, and a curved portion may be formed on the positive electrode tab separately from the connection area. This reduces stress that occurs when external force is applied after the electricity storage device 100 is manufactured. Therefore, the reliability of the power storage device 100 can be improved.

[0111] Furthermore, the positive electrode tab is not limited to being curved, and the material of the positive electrode current collector may be stainless steel, By using high-strength materials such as titanium and keeping the film thickness of the positive electrode current collector to 10 μm or less, the battery The structure may be such that stress caused by external force being applied after the device is manufactured can be easily alleviated.

[0112] 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.

[0113] Similarly to the positive electrode current collector 101, the negative electrode tabs of the negative electrode current collectors 105 and the sealing layer 121 The negative electrode lead 145 having the same structure is electrically connected by ultrasonic welding (FIG. 14(B)). When this happens, the negative electrode tab will have a curved section, just like the positive electrode tab, and the current collector material will be made stronger. Alternatively, a configuration may be adopted that makes it easier to relieve stress, such as by

[0114] [5. Glue parts of the exterior body] Next, the film 109a and the film 109b are used to connect the positive electrode 111, the positive electrode lead 141, and the negative electrode 111. The electrode 115 and the negative electrode lead 145 are sandwiched between the film 109a and the film 109b. In a part of b (the thermocompression bonding area 122a in FIG. 15(A)), the film 109a and The film 109b is bonded to the film 109b (FIG. 15(A)). The bonding can be performed by heat welding or the like. The film 109a and the film 109b may have irregularities. 15 and 16, the recesses of the film 109a and the exterior body 110 are shown only for the sake of simplicity. The convexities are omitted.

[0115] [6. Glue the other parts of the exterior body and inject the electrolyte] Next, film 109a is removed from the area where film 109b is not bonded. The electrolyte 108 is poured into the area sandwiched between the film 109a and the film 109b (FIG. 15(B)). )).

[0116] [7A.Seal] Then, while evacuating, the film 109a and the film 10 16(A)) of the unbonded portion of 9b (thermocompression bonding area 122b in FIG. 16(A)) is bonded. The film 109a and the film 109b constitute a bag-shaped exterior body 110. Figure 16(A)). These operations were carried out in a glove box or other suitable location to eliminate oxygen and water. The vacuum sealer should be used, for example, a vacuum sealer or a liquid injection sealer. The sealing method can be an impulse sealer, a heat sealer, or the like. When using a cooler, for example, heat for 3 seconds at a temperature of 175°C and a vacuum of 60 kPa. In addition, when using a heat sealer and not vacuuming, the temperature is, for example, 1 Heating is performed for 4 seconds at 65°C and a pressure of 0.3 MPa. The positive and negative electrodes may be pressurized from above. This pressure removes air bubbles that may have been mixed in when the electrolyte was injected. It can be removed from between the positive and negative electrodes.

[0117] [8A. Aging] Next, it is preferable to carry out charging and discharging for aging. The purpose of this test is to detect initial defects in the storage device and to measure the amount of stable charge and discharge current on the negative electrode active material during the initial charge and discharge. Specifically, this refers to the process of forming a coating at a temperature close to the upper limit of the battery operating temperature range. These include holding the battery in a charged state for an extended period of time at a high temperature, or undergoing one or more charge / discharge cycles. Furthermore, a step of releasing gas generated in the area covered by exterior body 110 may be included.

[0118] By forming a stable coating on the negative electrode active material during the initial charge / discharge, It is possible to prevent the consumption of carrier ions due to the formation of further coatings. Aging makes it possible to stabilize the performance of the energy storage device and to sort out defective cells. Cut.

[0119] In this embodiment, after one or more charge / discharge cycles, the exterior is removed as shown in FIG. 16(B). A portion of the body 110 is cut away to release the gas.

[0120] [9A.Resealing] Next, one side of the exterior body 110 cut off during aging (the thermocompression bonding portion in FIG. 16(C)) is The region 122c is sealed again (FIG. 16(C)). Through the above steps, the electricity storage device 100 is manufactured. It is possible.

[0121] Next, the other parts of the exterior are glued together, the electrolyte is injected, and then the battery is sealed, aged, and resealed. Different ways to do this are described.

[0122] [7B.Seal] While evacuating, the film 109a and the film 109b are heated and pressurized. The unbonded portion (thermocompression bonded area 122d in FIG. 17(A)) is bonded, and the filler The film 109a and the film 109b constitute a bag-shaped exterior body 110 (FIG. 17). (A)). At this time, the adhesive strength of the two films is such that they can be peeled off by applying external force. For example, in the thermocompression bonding area 122d, the bonding is performed at a lower temperature than the conditions described in 7A. If you use an impulse sealer, the temperature should be 13 Heating is sufficient for 3 seconds at 0°C to 140°C and a vacuum of 60kPa. When using a sealer and not vacuuming, for example, the temperature should be between 130°C and 140°C. The pressure is 0.3 MPa and the heating is carried out for 4 seconds.

[0123] [8B. Aging] Next, aging is performed in the same manner as described in 8A.

[0124] In this embodiment, after one or more cycles of charge and discharge are performed as aging, the battery is charged as shown in FIG. As shown in FIG. 1, a force is applied to peel the two films apart at the thermocompression bonding area 122d. and let the gas out.

[0125] [9B.Resealing] Next, the peeled area is sealed again (thermocompression bonded area 122e in FIG. 17(C)). By using this manufacturing method, it is possible to manufacture the power storage device 100 in which the inner periphery of the thermocompression bonding region is circular. Cut.

[0126] Next, referring to FIGS. 18 to 20, the positive electrode and the negative electrode described in [3. Laminating the positive electrode and the negative electrode] are laminated. Another example of a method for stacking negative electrodes will be described.

[0127] FIG. 18 shows a separator 107 (see FIG. 18(A)) having a shape in which a plurality of circles are connected. 18(B), a method for laminating electrodes 170 is shown. By folding the electrode 170 into an accordion-like shape, the electrode 170 can be stacked. .

[0128] The electrode 170 refers to the positive electrode 111 or the negative electrode 115. For the sake of simplicity, FIG. 19, the positive electrode 111 and the negative electrode 115 are both referred to as electrodes 170.

[0129] FIG. 19 shows a separator 107 (see FIG. 19(A)) having a shape in which a plurality of circles are connected. 19B. A method for stacking electrodes 170 to form a stacked body 175 (FIG. 19B) is shown. The laminate 175 includes an electrode 170, a separator 107, and a lead electrode. A cross-sectional view of the laminate 175 taken along the dashed line AB indicated by the arrow ) is shown in FIG. 19(C). As shown in the figure, the separator 107, which has a shape of a plurality of connected circles, is wound around the electrode 17. The electrodes 170 can also be stacked by sandwiching a zero between them.

[0130] The laminate 175 may be formed by combining a plurality of laminates. The body 175 includes a plurality of first laminates 171 and a plurality of second laminates 172. FIG. 20(A) is a cross-sectional view of the first laminate 171, and FIG. 20(B) is a cross-sectional view of the second laminate 172. 20(C) is another example of a cross-sectional view of the laminate 175 taken along the dashed line AB shown in FIG. 19(B). In FIG. 20(C), for clarity, the first stacked body 171 and the second stacked body 17, the body 172 and the separator 107B are selectively shown.

[0131] As shown in FIG. 20(A), in the first laminate 171, the positive electrode active layer is formed on both sides of the positive electrode current collector 101. The positive electrode 111, separator 107A, and negative electrode current collector 105 are in contact with the material layer 102. The negative electrode 115, separator 107A, and positive electrode current collector 101 are in contact with the active material layer 106. The positive electrode 111 in contact with the electrode active material layer 102 is laminated in this order. As shown in the figure, in the second laminate 172, the negative electrode active material layers 106 are in contact with both sides of the negative electrode current collector 105. The cathode active material layer 102 is formed on both sides of the anode 115, separator 107A, and cathode current collector 101. The negative electrode active material layer 106 is formed on both sides of the positive electrode 111, separator 107A, and negative electrode current collector 105 that are in contact with each other. The negative electrode 115 in contact with the negative electrode 115 is laminated in this order.

[0132] As shown in FIG. 20(C), a plurality of first stacks 171 and a plurality of second stacks 172 In other words, the first stack of the separator 107B is covered by the separator 107B. The separator 171 and the plurality of second laminates 172 are disposed between the wound separators 107B. It has been done.

[0133] The positive electrode 111 of the first laminate 171 arranged on the outermost side is one of the positive electrode current collectors 101. It is preferable to use one in which the positive electrode active material layer 102 is in contact with one surface.

[0134] In addition, in FIGS. 20(A) and 20(B), the first laminate and the second laminate have three electrodes and two However, one embodiment of the present invention is not limited to this. In addition, the power storage device 10 may have a configuration having three or more separators. The capacity of the battery can be further improved. When the number of electrodes is small, the power storage device can be more easily bent. In FIG. 20C, the power storage device 100 includes three sets of the first stack body 171 and one set of the second stack body 172. Although the configuration having two stacked bodies is shown, one embodiment of the present invention is not limited to this. By increasing the number of stacked bodies, the capacity of the power storage device 100 can be further improved. It is also possible to have a configuration with fewer laminates. The power storage device can be more easily bent.

[0135] Next, a method for providing irregularities on the film used for the exterior body 110 will be described with reference to FIG. do.

[0136] FIG. 21(A) shows a mold 161 and a mold 162 used to provide the film with irregularities. The mold 161 and the mold 162 each have a plurality of circular protrusions 160. By sandwiching the film 109a between the film 109a and the film 109b (see FIGS. 21(B) and 21(C)), 109a may be provided with circular projections and recesses.

[0137] Figure 21(D), (E), and (F) show cross-sectional views of the film and mold when the film is sandwiched between the molds. The convex portion of the mold 161 and the convex portion of the mold 162 are respectively as shown in FIG. 21(D). As shown in FIG. 21(E), the protrusion of the mold 161 may be designed to fit the mold. The convex portion of the mold 162 may overlap with the flat plate 16. 3 and the mold 161, the film 109a is sandwiched between the mold 161 and the film 109a. can be set up.

[0138] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0139] (Embodiment 3) In this embodiment, a power storage device according to one embodiment of the present invention will be described with reference to FIGS. 22, 23, and 24. The materials that can be used for the above will be described in detail below.

[0140] [1. Positive electrode] The positive electrode 111 includes a positive electrode current collector 101 and a positive electrode active material layer 102 in contact with the positive electrode current collector 101. It consists of:

[0141] The positive electrode current collector 101 is made of metal such as stainless steel, gold, platinum, aluminum, titanium, etc. Materials such as these alloys that are highly conductive and do not dissolve at the potential of the positive electrode can be used. Also, improves the heat resistance of silicon, titanium, neodymium, scandium, molybdenum, etc. Aluminum alloys with added elements can be used. It may be formed from a metal element that reacts with silicon to form a silicide. The metal elements that can be used are zirconium, titanium, hafnium, vanadium, niobium, and tantalum. Examples of the metals include zinc, chromium, molybdenum, tungsten, cobalt, and nickel. 1 is a foil, plate (sheet), mesh, punched metal, expanded metal, etc. The positive electrode current collector 101 has a thickness of 5 μm or more and 30 μm or less. It is also preferable to use a material such as graphite on the surface of the positive electrode current collector 101. A dark coat layer may be provided.

[0142] The positive electrode active material layer 102 contains a positive electrode active material and a binder (binder) for increasing the adhesion of the positive electrode active material. The positive electrode active material layer 102 may contain an indium ion, a conductive additive for increasing the conductivity of the positive electrode active material layer 102, or the like.

[0143] The positive electrode active material used in the positive electrode active material layer 102 may have an olivine-type crystal structure or a layered rock salt-type There are composite oxides with a crystalline structure or a spinel-type crystalline structure. , for example, LiFeO2, LiCoO2, LiNiO2, LiMn2O4, V2O5, C Compounds such as r2O5 and MnO2 are used.

[0144] 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.

[0145] 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 M x O2(0 <x<1 ) (M=Co, Al, etc.)) can improve the characteristics of the electricity storage device using this. This is preferable.

[0146] In addition, the positive electrode active material is a compound having the composition formula Li a Mn b M c O d Lithium-manganese can be expressed as A manganese composite oxide can be used. Here, element M is selected from elements other than lithium and manganese. The selected metal element, silicon, or phosphorus is preferably used, and nickel is preferred. Further, when measuring the entire particle of the lithium manganese composite oxide, When the value is 0 <a / (b+c)<2、かつc>0 and 0.26≦(b+c) / d<0.5, It is preferable that the metal, silicon, and The composition of phosphorus, etc. is measured using, for example, an ICP-MS (inductively coupled plasma mass spectrometer). The oxygen composition of the entire particle of the lithium manganese composite oxide can be determined by, for example, ED It can be measured using energy dispersive X-ray analysis (ICP- In combination with MS analysis, molten gas analysis and XAFS (X-ray absorption fine structure) analysis were used to evaluate the valence. ​The lithium manganese composite oxide is a compound oxide containing at least lithium It refers to oxides containing thium and manganese, and also contains chromium, cobalt, aluminum, nickel, Iron, magnesium, molybdenum, zinc, indium, gallium, copper, titanium, niobium, silicon It may contain at least one element selected from the group consisting of silicon, phosphorus, etc. stomach.

[0147] In order to achieve high capacity, the crystal structure, crystal orientation, or oxygen content of the surface and center portions must be adjusted. It is preferable to use a lithium manganese composite oxide having regions with different amounts of manganese. In order to obtain a lithium manganese composite oxide with a composition formula of Li a Mn b Ni c O d (1.6 ≦a≦1.848, 0.19≦c / b≦0.935, 2.5≦d≦3) Furthermore, Li 1.68 Mn 0.8062 Ni 0.318 The formula is O3 It is particularly preferable to use a lithium manganese composite oxide. , Li 1.68 Mn 0.8062 Ni 0.318 Lithium manganese with the formula O3 The ratio of the amount of material (molar ratio) is Li2CO3:MnCO3:Ni Lithium manganese complex formed by adjusting the ratio of O to 0.84:0.8062:0.318 Therefore, the lithium manganese composite oxide has the composition formula Li 1.68 Mn0 .8062 Ni 0.318 It is expressed as O3, but the composition may deviate from this.

[0148] Lithium manganese composite oxide having regions with different crystal structures, crystal orientations or oxygen contents An example of a cross section of a particle is shown in FIG.

[0149] As shown in FIG. 22(A), the crystal structure, crystal orientation, or oxygen content of the region is different. The lithium manganese composite oxide has a first region 331, a second region 332, and a third region The second region 332 is preferably at least partly outside the first region 331. The outer part of the particle is in contact with the surface of the particle. The region 333 has a region that coincides with the surface of the particle having the lithium manganese composite oxide. It is preferable that

[0150] Also, as shown in FIG. 22(B), the first region 331 is not covered by the second region 332. The second region 332 may have an area that is not covered by the third region 333. For example, the first region 331 may have a region where the third region 333 is in contact with the first region 331. The first region 331 may be either the second region 332 or the third region 333. It may have areas that are not covered by the

[0151] The second region 332 preferably has a different composition than the first region 331 .

[0152] For example, the compositions of the first region 331 and the second region 332 are measured separately, and the first region 331 has lithium, manganese, element M and oxygen, and the second region 332 has lithium, manganese, element M and oxygen. the first region 331 having lithium, manganese, the element M, and oxygen; The atomic ratio of oxygen is expressed as a1:b1:c1:d1, and the atomic ratio of lithium and manganese in the second region 332 is expressed as a1:b1:c1:d1. The atomic ratio of Gunn, element M, and oxygen is expressed as a2:b2:c2:d2. The compositions of the first region 331 and the second region 332 are, for example, TE Measurement by EDX (Energy Dispersive X-ray Analysis) using M (Transmission Electron Microscope) It is sometimes difficult to measure the lithium composition using EDX. Therefore, in the following, the difference in composition between the first region 331 and the second region 332 is due to the difference in elements other than lithium. Here, d1 / (b1+c1) is preferably 2.2 or more, and 2.3 or more. It is more preferable that the ratio is 2.35 or more and 3 or less, and further more preferable that the ratio is 2.35 or more and 3 or less. 2 / (b2+c2) is preferably less than 2.2, more preferably less than 2.1. It is preferable that the ratio is 1.1 or more and 1.9 or less. The composition of the entire lithium manganese composite oxide particle including the region 331 and the second region 332 is the same as that of the previous It is preferable that the above-mentioned condition 0.26≦(b+c) / d<0.5 is satisfied.

[0153] The manganese contained in the second region 332 is different from the manganese contained in the first region 331. The element M contained in the second region 332 may have a valence of 0.01 to 0.01. The element M may have a different valence from the element M.

[0154] More specifically, the first region 331 is made of lithium manganese having a layered rock salt type crystal structure. The second region 332 is preferably a composite oxide. It is preferable that the lithium manganese composite oxide is a lithium manganese composite oxide.

[0155] Here, if there is a spatial distribution in the composition of each region or the valence of elements, for example, The composition and valence of each of the regions are evaluated, and the average value is calculated. stomach.

[0156] A transition layer may also be provided between the second region 332 and the first region 331. A transition layer is, for example, a region where the composition changes continuously or stepwise. The transition layer is a region where the crystal structure changes continuously or stepwise. The second region 3 is a region where the lattice constant of the crystal changes continuously or stepwise. A mixed layer may be provided between the first region 32 and the second region 331. Here, the mixed layer may be, for example, a layer of different The mixed layer refers to a mixture of two or more crystals having different crystal orientations. For example, it refers to a mixture of two or more crystals with different crystal structures. For example, this refers to the case where two or more crystals with different compositions are mixed together.

[0157] The third region 333 can be made of carbon or a metal compound. For example, cobalt, aluminum, nickel, iron, manganese, titanium, zinc, lithium Examples of metal compounds include oxides and fluorides of these metals. It can be obtained.

[0158] Of the above, it is particularly preferable that the third region 333 contains carbon. Carbon has good electrical conductivity. Therefore, by using carbon-coated particles in the electrodes of an electricity storage device, the resistance of the electrodes can be reduced, for example. Furthermore, since the third region 333 contains carbon, the resistance of the third region The second region 332 in contact with the third region 333 can be oxidized. The graphene oxide may be reduced. Graphene and reduced graphene oxide are known to have high electrical conductivity. It has excellent electrical properties and excellent physical properties such as high flexibility and mechanical strength. Furthermore, the lithium manganese composite oxide particles can be efficiently coated.

[0159] The third region 333 contains carbon such as graphene, and thus the lithium manganese The cycle characteristics of an electricity storage device using the composite oxide as a positive electrode material can be improved.

[0160] The thickness of the carbon-containing layer is preferably 0.4 nm or more and 40 nm or less.

[0161] The lithium manganese composite oxide may have an average particle size of, for example, 5 nm or more. It is preferable that the thickness is 0 μm or less, and more preferably 100 nm or more and 500 nm or less. In addition, the specific surface area is 5m 2 / g or more 15m 2 / g or less. The average particle size of the secondary particles is preferably 5 μm or more and 50 μm or less. Observation using SEM (scanning electron microscope) or TEM, or laser diffraction and scattering method The specific surface area can be measured by a particle size distribution analyzer or the like. It can be measured.

[0162] Alternatively, a composite material (general formula LiMPO4 (M is Fe(II), Mn (II), Co(II), Ni(II), or one or more of the following can be used. Representative examples of MPO4 include LiFePO4, LiNiPO4, LiCoPO4, and LiM nPO4, LiFe a Ni b PO4, LiFe a Cob PO4, LiFe a 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), LiFe c Ni d Co e PO4, LiFe c Ni d Mn e PO4, LiNi c Co d Mn e PO4 (c + d + e is less than or equal to 1, 0 < c < 1, 0 < d < 1, 0 < e < < 1), LiFe f Ni g Co h Mn i PO4 (f + g + h + i is less than or equal to 1, 0 < f < 1, 0 < g < 1, 0 < h < 1, 0 < i < 1), etc. Lithium compounds can be used as materials.

[0163] In particular, LiFePO4 satisfies the requirements for a cathode active material, such as safety, stability, high capacity density, and the presence of lithium ions that can be extracted during initial oxidation (charging), in a balanced manner. Therefore, it is preferable.

[0164] Or, composite materials such as the general formula Li (2-j) MSiO4 (M is one or more of Fe(II), Mn(II), Co( II), Ni(II), 0 ≤ j ≤ 2) can be used. General formula Li (2-j) MSiO4 representative examples include Li (2-j) FeSiO4, Li (2 -j) NiSiO4, Li (2-j) CoSiO4, Li (2-j) MnSiO4, Li (2-j) Fek Ni 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 (where k + l is less than or equal to 1, 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 (where m + n + q is less than or equal to 1, 0 < m < 1, 0 < n < 1, 0 < q < 1) , Li (2-j) Fe r Ni s Co t Mn u SiO4 (where r + s + t + u is less than or equal to 1, 0 < r <1, 0 < s < 1, 0 < t < 1, 0 < u < 1), etc. Lithium compounds can be used as materials and so on.

[0165] Also, as the positive electrode active material, A x M2(XO4)3 (A = Li, Na, Mg, M = Fe, M n, Ti, V, Nb, X = S, P, Mo, W, As, Si) represented by the general formula of NASICON type compounds can be used. NASICON type compounds include Fe2(MnO4)3, F e2(SO4)3, Li3Fe2(PO4)3, etc. Also, as the positive electrode active material, Li It is represented by the general formula 2MPO4F, Li2MP2O7, Li5MO4 (M=Fe, Mn) Compounds, perovskite-type fluorides such as NaFeF3 and FeF3, TiS2, MoS2, etc. Metal chalcogenides (sulfides, selenides, tellurides), inverse spinels such as LiMVO4 Oxides with a vanadium-type crystal structure (V2O5, V6O 13 , LiV3 O8, etc.), manganese oxides, organic sulfur compounds, and other materials can be used.

[0166] 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 as a positive electrode active material. It can be used.

[0167] Although not shown, a conductive material such as a carbon layer may be provided on the surface of the positive electrode active material layer 102. The conductivity of the electrode can be improved by providing a conductive material such as a carbon layer. For example, the carbon layer covering the positive electrode active material layer 102 may be formed by adding glucose or the like when baking the positive electrode active material. It can be formed by mixing carbohydrates.

[0168] The average particle size of the primary particles of the granular positive electrode active material is 50 nm or more and 100 μm or less. It is good.

[0169] As the conductive additive, for example, a carbon material, a metal material, or a conductive ceramic material is used. In addition, a fibrous material may be used as the conductive additive. The content of the conductive additive is preferably 1 wt% or more and 10 wt% or less, and more preferably 1 wt% or more and 5 wt% or less. % or less is more preferable.

[0170] The conductive additive can form an electrically conductive network in the electrode. This allows the electrical conduction path between the active materials to be maintained. By adding such an active material, it is possible to realize an active material layer having high electrical conductivity.

[0171] Examples of the conductive additive include natural graphite, artificial graphite such as mesocarbon microbeads, and carbon fiber. Examples of carbon fibers that can be used include mesophase pitch carbon fibers. Carbon fibers such as isotropic pitch-based carbon fibers can be used. Carbon nanofibers and carbon nanotubes can be used. The tube can be produced by, for example, vapor phase growth method. For example, carbon black (acetylene black (AB) etc.), graphite particles Carbon materials such as graphene and fullerene can be used. Metal powders and fibers such as nickel, aluminum, silver, and gold, as well as conductive ceramic materials, etc. It can be used.

[0172] Flaky graphene has excellent electrical properties, such as high conductivity, as well as flexibility and functionality. Graphene has excellent physical properties, such as mechanical strength, and is therefore used as a conductive additive. This makes it possible to increase the number of contact points and the contact area between the active materials.

[0173] In this specification, graphene refers to a single-layer graphene or a graphene having 2 to 100 layers. Single-layer graphene is a graphene consisting of a single atomic layer of carbon molecules with π bonds. Graphene oxide refers to a compound in which the graphene is oxidized. When graphene is formed by reducing graphene oxide, Not all of the oxygen contained in the graphene is released, and some of the oxygen remains in the graphene. When oxygen is present, the oxygen fraction is 2 atom percent of the total graphene as measured by XPS. % or more and 11 atomic % or less, preferably 3 atomic % or more and 10 atomic % or less c% or less.

[0174] Graphene allows for surface contact with low contact resistance, and is conductive even when thin. The conductivity is so high that even a small amount can efficiently form a conductive path within the active material layer.

[0175] When using an active material with a small average particle size, for example, an active material with a particle size of 1 μm or less, the specific surface area of ​​the active material In such cases, the area is large and more conductive paths are required to connect the active materials. Graphene is used, which has extremely high conductivity and can efficiently form conductive paths even in small amounts. It is particularly preferred that

[0176] An example of a cross-sectional structure in which graphene is used as a conductive additive in a positive electrode active material layer will be described below. Note that graphene may be used as a conductive additive in the negative electrode active material layer.

[0177] FIG. 23(A) shows a vertical cross-sectional view of the positive electrode active material layer 102 and the positive electrode current collector 101. The material layer 102 includes a positive electrode active material 322 in a particle form, graphene 321 as a conductive additive, and a binder. and an adhesive (also called a binder, not shown).

[0178] In the vertical cross section of the positive electrode active material layer 102, as shown in FIG. 23(A), In the inside of 2, the sheet-like graphene 321 is approximately uniformly arranged so as to be in surface contact with the positive electrode active material. In FIG. 23(A), graphene 321 is shown schematically by a thick line. However, it is actually a thin film having a thickness of a single layer or multiple layers of carbon molecules. 1 is disposed so as to encase or cover a plurality of granular positive electrode active materials 322, or Since the positive electrode active material 322 is formed so as to be stuck to the surface thereof, the positive electrode active material 322 is in surface contact with the positive electrode active material 322. In addition, the graphene 321 also comes into surface contact with each other, forming multiple graphene 321. It forms a more three-dimensional electrical conduction network.

[0179] This is because graphene oxide, which has extremely high dispersibility in polar solvents, is used to form graphene 321. The solvent is removed by evaporation from the dispersion medium containing uniformly dispersed graphene oxide. In order to reduce the graphene oxide to graphene, the graphene remaining in the positive electrode active material layer 102 is removed. Lafen 321 partially overlaps and covers the positive electrode active material to the extent that they are in surface contact with each other. The reduction of graphene oxide can be achieved by, for example, heat treatment. Alternatively, a reducing agent may be used.

[0180] Therefore, unlike granular conductive additives such as acetylene black, which come into point contact with the active material, graphite Since the 321 allows for surface contact with low contact resistance, the amount of conductive additive is increased. The positive electrode active material 322 and the graphene 321 are electrically connected to each other without any problem. Therefore, by increasing the ratio of the positive electrode active material 322 in the positive electrode active material layer 102, This makes it possible to increase the discharge capacity of the power storage device.

[0181] In addition, graphene is bonded to itself to form a mesh-like graphene (hereafter referred to as graphene network). When the active material is covered with a graphene net, Fennet can also function as a binder between particles. The amount of electrode can be reduced or eliminated, reducing the electrode volume and The ratio of the active material to the weight can be increased, i.e., the capacity of the power storage device can be increased. It can be done.

[0182] The positive electrode active material layer or the negative electrode active material layer includes graphene as a conductive additive. This configuration is particularly effective in a flexible power storage device.

[0183] FIG. 24(A) shows a conventional example in which acetylene black and other particulate conductive additives are used. 10 is a longitudinal cross-sectional view of a positive electrode active material layer 102 and a positive electrode current collector 101 when a conductive additive 323 is used. The positive electrode active material 322 is electrically conductive due to contact with the particulate conductive additive 323. A network has been formed.

[0184] FIG. 24(B) shows the case where the positive electrode active material layer 102 and the positive electrode current collector 101 of FIG. 24(A) are bent. As shown in FIG. 24(B), when a particulate conductive additive 323 is used as the conductive additive, the positive electrode As the active material layer 102 bends, the distance between the positive electrode active materials 322 changes. There is a risk that part of the electrical conduction network between the 22s will be broken.

[0185] On the other hand, the positive electrode active material layer 102 and the positive electrode FIG. 23(B) shows the case where the current collector 101 is bent. Graphene is a flexible sheet. Therefore, as the positive electrode active material layer 102 bends as shown in FIG. 23(B), the positive electrode active material 32 Even if the distance between the two changes, the electrical conduction network can be maintained.

[0186] The electrode used in the power storage device of one embodiment of the present invention can be manufactured by various methods. When forming an active material layer on a current collector using a coating method, the active material, binder, and conductive additive are separated. A dispersion medium (also called a solvent) is mixed to make a paste, which is then applied to the current collector. After that, if necessary, pressure such as roll press or plate press can be used. It may be compacted by pressing using a shrinking method.

[0187] Examples of the dispersion medium include water, N-methylpyrrolidone (NMP), and dimethylformamide. From the viewpoint of safety and cost, water can be used. It is preferable to use

[0188] The binder preferably contains, for example, a water-soluble polymer. For example, polysaccharides can be used. Examples of polysaccharides include carboxymethyl cellulose. CMC, methyl cellulose, ethyl cellulose, hydroxypropyl cellulose cellulose derivatives such as diacetyl cellulose and regenerated cellulose, and starch, etc. It is possible.

[0189] In addition, styrene-butadiene rubber (SBR), styrene-isoprene Styrene rubber, acrylonitrile butadiene rubber, butadiene rubber, fluororubber, It is preferable to use rubber materials such as ethylene-propylene-diene copolymers. It is more preferable to use the rubber material in combination with the water-soluble polymer described above.

[0190] Alternatively, the binder may be polystyrene, polymethyl acrylate, or polymethyl methacrylate. Polymethyl methacrylate (PMMA), sodium polyacrylate, polyvinyl Polyvinyl alcohol (PVA), polyethylene oxide (PEO), polypropylene oxide, Polyimide, polyvinyl chloride, polytetrafluoroethylene, polyethylene, polypropylene polyethylene, isobutylene, polyethylene terephthalate, nylon, polyvinylidene fluoride ( PVdF), polyacrylonitrile (PAN), polyvinyl chloride, ethylene propylene It is preferable to use materials such as diene polymers, polyvinyl acetate, nitrocellulose, etc. stomach.

[0191] Two or more of the above binders may be used in combination.

[0192] The content of the binder relative to the total amount of the positive electrode active material layer 102 is 1 wt % or more and 10 wt % or less. It is preferable that the content of the hydroxybenzoate is 2 wt% or more and 8 wt% or less, more preferable that the content of the hydroxybenzoate is 3 wt% or more and 5 wt% or less. In addition, the content of the conductive additive relative to the total amount of the positive electrode active material layer 102 is preferably 1 wt % or more. The content is preferably from 1 to 10 wt%, more preferably from 1 to 5 wt%.

[0193] When the positive electrode active material layer 102 is formed by a coating method, the positive electrode active material, the binder, and the conductive additive are mixed. The positive electrode paste (slurry) is prepared by mixing the above, and is then applied onto the positive electrode current collector 101 and dried. That's fine.

[0194] [2. Negative electrode] The negative electrode 115 is composed of a negative electrode current collector 105 and a negative electrode active material layer 10 formed on the negative electrode current collector 105. It consists of 6 etc.

[0195] The negative electrode current collector 105 is made of metals such as stainless steel, gold, platinum, iron, copper, titanium, and the like, and Use materials such as alloys that are highly conductive and do not alloy with carrier ions such as lithium. In addition, heat-resistant materials such as silicon, titanium, neodymium, scandium, and molybdenum can be used. An aluminum alloy containing an element that improves the resistance can be used. 5 is a foil, plate (sheet), mesh, punched metal, expanded metal, etc. The negative electrode current collector 105 has a thickness of 5 μm or more and 30 μm or less. It is also preferable to use a material that is coated with graphite or the like on the surface of the negative electrode current collector 105. A dark coat layer may be provided.

[0196] If the negative electrode current collector is made of a strong material such as stainless steel or titanium, the negative electrode active material This is preferable because it can withstand deformation of the negative electrode current collector due to expansion of the negative electrode active material layer. As a battery, materials that undergo large volume changes during charging and discharging, such as materials containing silicon, are used. This is particularly suitable in such cases.

[0197] The negative electrode active material layer 106 contains, in addition to the negative electrode active material, a binder (binder) for increasing the adhesion of the negative electrode active material. The negative electrode active material layer 106 may contain an indium ion or a conductive additive for increasing the conductivity of the negative electrode active material layer 106. The binder and conductive additive materials used in the active material layer are the same as those used in the positive electrode active material layer. The materials of the conductive additives can be taken into consideration.

[0198] The negative electrode active material is a material that can dissolve and deposit lithium or undergo a reversible reaction with lithium ions. Materials that can be used include lithium metal, carbon-based materials, alloy-based materials, etc. can.

[0199] 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 ) and is therefore preferable.

[0200] Carbon materials include graphite, easily graphitizable carbon (soft carbon), and non-graphitizable carbon (hard carbon). Examples include carbon nanotubes, graphene, and carbon black.

[0201] Graphite includes mesocarbon microbeads (MCMB), coke-based artificial graphite, and pitch. These include artificial graphite such as spheroidized artificial graphite, and natural graphite such as spheroidized natural graphite.

[0202] When lithium ions are inserted into graphite (when lithium-graphite intercalation compounds are formed), It exhibits a potential as low as that of lithium metal (0.1-0.3V vs. Li / Li + ).child This allows the lithium-ion battery to exhibit a high operating voltage. , relatively high capacity per unit volume, small volume expansion, inexpensive, and comparable to lithium metal This is preferable because it has advantages such as higher safety compared to the conventional method.

[0203] In addition to the carbon materials mentioned above, the negative electrode active material is also made of a material that undergoes alloying and dealloying reactions with carrier ions. A material capable of carrying out charge and discharge reactions can be used. In the case of ions, for example, Mg, Ca, Al, Si, Ge, Sn, Pb, As, Sb, A material containing at least one of Bi, Ag, Au, Zn, Cd, Hg, and In, etc. Such elements have a large capacity compared to carbon, and silicon in particular has a theoretical The capacity is dramatically high at 4200mAh / g. Therefore, the use of silicon as the negative electrode active material Materials using such elements are preferably Mg2Si, Mg2Ge , Mg2Sn, SnS2, V2Sn3, FeSn2, CoSn2, Ni3Sn2, Cu6 Sn5, Ag3Sn, Ag3Sb, Ni2MnSb, CeSb3, LaSn3, La3C Examples include o2Sn7, CoSb3, InSb, and SbSn.

[0204] In addition, the negative electrode active material is SiO, SnO, SnO2, titanium dioxide (TiO2), lithium Sodium titanium oxide (Li4Ti5O 12 ), lithium-graphite intercalation compound (Li x C6), Niobium pentoxide (Nb2O5), tungsten oxide (WO2), molybdenum oxide (MoO2 ) and other oxides can be used.

[0205] SiO refers to silicon oxide powder, and SiO y Also written as (2>y>0) SiO may contain silicon-rich portions. For example, SiO may be SiO 3, Si3O4, or Si2O, or a material containing one or more of these, or Si powder It also includes mixtures of silicon dioxide (SiO2) and other elements (carbon, nitrogen, iron, aluminum). It may also contain aluminum, copper, titanium, calcium, manganese, etc. Si, amorphous Si, polycrystalline Si, Si2O3, Si3O4, Si2O, SiO2 SiO is a colored material. Si is not SiO O x (X is 2 or more), it is colorless and transparent or white, and can be distinguished. After fabricating a power storage device using SiO as a material for the power storage device, the device is repeatedly charged and discharged. When SiO is oxidized, it may be transformed into SiO2.

[0206] In addition, the negative electrode active material is a composite nitride of lithium and transition metals, which has a Li3N structure. Li 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 / cm 3 ) And preferable.

[0207] 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 lithium-transition metal nitride, a complex nitride of lithium and a transition metal can be used.

[0208] In addition, a material that undergoes a conversion reaction can also be used as the negative electrode active material. , cobalt oxide (CoO), nickel oxide (NiO), iron oxide (FeO), etc. A transition metal oxide that does not undergo an alloying reaction with the negative electrode active material may be used. Further materials that undergo a reaction include Fe2O3, CuO, Cu2O, RuO2, and Cr2O Third order oxide, CoS 0.89 , NiS, CuS and other sulfides, Zn3N2, Cu3N, G Nitrides such as e3N4, phosphides such as NiP2, FeP2, CoP3, FeF3, BiF3 This also occurs with fluorides such as those mentioned above. Since the potential of the fluorides is high, they are not suitable for use as positive electrode active materials. That's fine.

[0209] When the negative electrode active material layer 106 is formed by a coating method, the negative electrode active material and the binder are mixed together to form the negative electrode active material layer 106. An electrode paste (slurry) may be prepared, applied to the negative electrode current collector 105, and then dried.

[0210] Graphene may be formed on the surface of the negative electrode active material layer 106. When silicon is used, the volume due to the absorption and release of carrier ions during the charge and discharge cycle is Since the change in the negative electrode current collector 105 is large, the adhesion between the negative electrode active material layer 106 and the negative electrode current collector 105 is reduced, and the charge / discharge Therefore, the surface of the negative electrode active material layer 106 containing silicon is When graphene is formed on silicon, the volume of silicon changes during the charge-discharge cycle. In addition, it is possible to suppress a decrease in the adhesion between the negative electrode current collector 105 and the negative electrode active material layer 106. This is preferable because it reduces deterioration of the pond characteristics.

[0211] In addition, a coating of an oxide or the like may be formed on the surface of the negative electrode active material layer 106. The film formed by the decomposition of the electrolyte releases the 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 it on the surface of the layer 106, it is possible to suppress or prevent the occurrence of irreversible capacity. .

[0212] The coating that coats the negative electrode active material layer 106 may contain niobium, titanium, vanadium, tungsten, or the like. aluminum, tungsten, zirconium, molybdenum, hafnium, chromium, aluminum or or silicon oxide film, or a film containing one of these elements and lithium Such a coating can be formed on the negative electrode by the decomposition products of conventional electrolytes. This film is sufficiently dense compared to the coating formed on the surface.

[0213] 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.

[0214] The film that covers the negative electrode active material layer 106 can be formed by, for example, a sol-gel method. The sol-gel method is a method in which a solution of metal alkoxides and metal salts is subjected to hydrolysis and polymerization. This method involves creating a gel that loses fluidity through a condensation 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 are mixed homogeneously at the molecular level. For this reason, the raw material for the metal oxide film at the solvent stage can be mixed with a negative electrode active material such as graphite. By adding the active material, it is possible to easily disperse the active material in the gel. A coating can be formed on the surface of the electrode active material layer 106. By using the coating, This can prevent the capacity of the device from decreasing.

[0215] [3. Separator] The separator 107 may be made of a material such as cellulose, polypropylene, or polyethylene. Styrene (PE), polybutene, nylon, polyester, polysulfone, polyacrylonitrile tolyl, polyvinylidene fluoride, tetrafluoroethylene, polyphenylene sulfide In addition, nonwoven fabric such as glass fiber or glass fiber and A membrane made of polymer fibers may be used. In order to improve heat resistance, polyester A separator made of nonwoven fabric with a ceramic coating or aramid coating may also be used. .

[0216] [4. Electrolyte] The solvent of the electrolyte solution 108 used in the electricity storage device 100 is preferably an aprotic organic solvent. , for example, ethylene carbonate (EC), propylene carbonate (PC), butylene Carbonate, chloroethylene carbonate, vinylene carbonate, gamma-butyrolactone γ-valerolactone, dimethyl carbonate (DMC), diethyl carbonate (D EC), 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 can be used in combinations and ratios of:

[0217] 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 device rises due to an internal short circuit or overcharging, This can prevent the electricity storage device from exploding or catching fire.

[0218] 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(FSO2)2, LiN(CF3SO2)2, LiN(C4F9 SO2)(CF3SO2), LiN(C2F5SO2)2, or one of these lithium salts Two or more of these may be used in any combination and in any ratio.

[0219] A polymer may be added to the electrolyte to make it gel. This improves safety against electrolytic degradation, etc. Also, it is possible to make the electricity storage device thinner and lighter. Examples of polymers that can turn a liquid into a gel include polyalkylene oxides, Polyacrylonitrile, polyvinylidene fluoride, polyacrylate, polymethacrylate In this specification and the like, for example, poly(vinyl fluoride) can be used. The vinylidene polymer means a polymer containing polyvinylidene fluoride, and poly(vinylidene fluoride) The polymers formed include polyvinylidene-hexafluoropropylene copolymers. It may have a porous shape.

[0220] The above polymers can be qualitatively analyzed using FT-IR (Fourier transform infrared spectrophotometer) etc. For example, polyvinylidene fluoride polymers can be analyzed by the spectrum obtained by FT-IR. In the spectrum, there is an absorption indicating a C—F bond. The spectrum obtained by T-IR shows absorption indicating a C≡N bond.

[0221] In addition, the electrolyte used in the electricity storage device is free from granular waste and elements other than the constituent elements of the electrolyte (hereinafter referred to as "single"). 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. It is more preferable that the content of vinylene carbonate in the electrolyte is 0.01% or less. Additives such as cellulose may also be added.

[0222] In addition, instead of an electrolytic solution, a solid electrolyte containing inorganic materials such as sulfides or oxides is used. When a solid electrolyte is used, the installation of a separator or spacer becomes unnecessary. In addition, the entire battery can be solidified, eliminating the risk of leakage and dramatically improving safety. do.

[0223] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0224] (Fourth embodiment) In this embodiment, an example in which the power storage device described in Embodiment 1 is mounted in an electronic device will be described. Reveal.

[0225] An example of mounting a flexible power storage device on a wristband-type electronic device is shown in FIG. The armband type device 7300 can be worn on an arm 7301 and has a curved surface. The display includes a display unit and a bendable power storage device.

[0226] In addition, in the display unit, a display element, a display device which is a device having a display element, a light-emitting element, and A light-emitting device, which is a device having a light-emitting element, can be formed in various forms or can include various elements. The display element, the display device, the light-emitting element, or the light-emitting device may include, for example, an EL (electroluminescent) Electroluminescence) elements (EL elements including organic and inorganic materials, organic EL elements, inorganic EL elements), LEDs (white LEDs, red LEDs, green LEDs, blue LEDs, etc.), transistors (transistors that emit light according to the current), electron-emitting devices, liquid crystal devices, electronic ink, Electrophoretic element, Grating Light Valve (GLV), Plasma Display (PDP) ), display elements using MEMS (microelectromechanical systems), digital Digital Micromirror Device (DMD), Digital Micro Shutter (DMS), MIRASOL®, an IMOD (Interference Modulation) element shutter-type MEMS display element, optical interference-type MEMS display element, electro using wetting elements, piezoelectric ceramic displays, or carbon nanotubes In addition to these, display elements, display devices, etc. The light emitting element or light emitting device is configured to provide contrast, brightness, reflection, etc., by electrical or magnetic action. The display medium may have a variable reflectance, transmittance, etc. Examples include EL displays. is a field emission display (FED) or SED type flat panel display (SED:Surface-conduction Electron-emitter An example of a display device using a liquid crystal element is a liquid crystal display. Play (Transmissive LCD, Semi-Transmissive LCD, Reflective LCD , direct-view LCDs, projection LCDs, etc. Electronic ink, electronic powder An example of a display device using a fluid (registered trademark) or an electrophoretic element is electronic paper. In addition, when realizing a semi-transmissive liquid crystal display or a reflective liquid crystal display, In this case, it is sufficient that a part or all of the pixel electrode functions as a reflective electrode. For example, a part or all of the pixel electrodes may be made of aluminum, silver, etc. Furthermore, in this case, a memory circuit such as an SRAM can be provided under the reflective electrode. This makes it possible to further reduce power consumption. In this case, placing graphene or graphite under the LED electrodes or nitride semiconductors may Graphene or graphite may be formed into a multilayer film by stacking multiple layers. By providing graphene or graphite on the surface of the silicon substrate, a nitride semiconductor, for example, It is possible to easily form a film such as an n-type GaN semiconductor layer with crystallinity. An LED can be constructed by providing a p-type GaN semiconductor layer having a crystal structure. An AlN layer is placed between graphene or graphite and a crystalline n-type GaN semiconductor layer. The GaN semiconductor layer of the LED may be formed by MOCVD. However, by providing graphene, the GaN semiconductor layer of the LED can be grown by sputtering. It is also possible to form a film by

[0227] Furthermore, the armband device 7300 preferably has one or more functional elements, e.g. For example, sensors for force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetic Air, temperature, chemicals, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity It is also possible to use sensors that include the function of measuring gradient, vibration, smell, or infrared rays. The display device may also have functional elements such as a touch panel, an antenna, a power generation element, and a speaker.

[0228] For example, the armband type device 7300 is worn on the user's arm at night and the display unit is illuminated. If this is done, traffic safety can be improved. Contractors can wear and operate the armband-type device 7300 on their arms to work safely. It is easy to communicate and obtain other people's location information.

[0229] An example of mounting a flexible power storage device in another electronic device is shown in FIG. Examples of electronic devices to which the power storage device is applied include television sets (televisions, (also known as TV receivers), computer monitors, digital cameras, digital video digital cameras, digital photo frames, mobile phones (also called mobile phones or mobile phone devices), Examples include portable game machines, personal digital assistants, sound players, and large game machines such as pachinko machines. It can be obtained.

[0230] Furthermore, flexible electricity storage devices can be used for the interior or exterior walls of houses or buildings, or for the interior or exterior of automobiles. It is also possible to incorporate it along the curved surface of the exterior.

[0231] FIG. 26A 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.

[0232] FIG. 26B 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. The power storage device 7407 is a thin power storage device. The power storage device 7407 is fixed in a state in which the resistor 7408 is electrically connected to the current collector 7409. For example, the current collector 7409 is made of copper foil, and some of it is made of gallium. Alloying improves adhesion between the current collector 7409 and the active material layer in contact with it. This allows the power storage device 7407 to have high reliability even when bent. .

[0233] FIG. 26(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. 26E shows the bent state of the power storage device 7104. When the device is worn on the user's arm in a detached state, the housing may deform and cause damage to part of the power storage device 7104 or The total curvature changes. The degree of curvature at any point on the curve is expressed as the radius of the corresponding circle. The value expressed is the radius of curvature, and the reciprocal of the radius of curvature is called the curvature. Specifically, the radius of curvature is a part of the main surface of the housing or the power storage device 7104 within a range of 40 mm to 150 mm The radius of curvature of the main surface of the power storage device 7104 is 40 mm or more and 150 mm or less. High reliability can be maintained if the distance is within the range of mm or less.

[0234] Furthermore, the flexible power storage device that can be bent by applying external force is suitable for use in various electronic devices. For example, the stove 75 shown in FIG. 26(F) can be mounted in a space-efficient manner. 00 is a module 7511 attached to a main body 7512, and the module 7511 is a storage The storage tank includes a thermoelectric generator 7501, a motor, a fan, an air outlet 7511a, and a thermoelectric generator. In the heater 7500, fuel is poured into the opening 7512a, ignited, and then the electricity of the electricity storage device 7501 is charged. The motor and fan of module 7511 are rotated using force, and the air flows out of air outlet 7511a. This allows the outside air to be efficiently drawn into the stove. Therefore, it is possible to make a stove with a strong firepower. Furthermore, the thermal energy obtained by burning fuel It is possible to cook on the upper grill 7513 using the heat energy. The energy is converted into electricity by the thermoelectric generator of the module 7511 and charged into the storage device 7501. Furthermore, the power stored in the power storage device 7501 can be supplied from the external terminal 7511b. It can be output.

[0235] Furthermore, a wearable device as shown in FIG. 27 is equipped with the power storage device described in the first embodiment. It can be posted.

[0236] For example, it can be mounted on a glasses-type device 400 as shown in FIG. The display device 400 has a frame 400a and a display unit 400b. By installing a power storage device in the temple of the 400a, the weight balance is good and it can be used continuously. The eyeglass-type device 400 may have a long gap.

[0237] It can also be installed in a headset type device 401. Headset type device 401 includes at least a microphone part 401a, a flexible pipe 401b, and an earphone. The flexible pipe 401b and the earphone section 401c have a storage battery. A location can be provided.

[0238] It can also be mounted on a device 402 that can be attached directly to the body. A power storage device 402b can be provided in the second thin housing 402a.

[0239] It can also be mounted on a device 403 that can be attached to clothing. A power storage device 403b can be provided in the thin housing 403a.

[0240] It can also be installed in a wristwatch type device 405. The wristwatch type device 405 has a display The display unit 405a or the belt unit 405b has: A power storage device may be provided.

[0241] An enlarged view of the wristwatch type device 405 is shown in FIG. A power storage device 405c is provided on the curved circular display portion 405a. For the display unit that can be used, please refer to the description of the display unit in Figure 25. The display unit 405a can display not only the time but also various information such as incoming emails and phone calls. The outer periphery of the display unit 405a of the wristwatch type device 405 can be displayed as shown in FIG. As shown in (C), the shape may be a distorted closed curve. A power storage device 405c can be installed.

[0242] It can also be mounted on a belt-type device 406. The belt-type device 406 is The belt portion 406a and the wireless power receiving portion 406b are provided inside the belt portion 406a. , a power storage device can be mounted.

[0243] The wristwatch type device 405 is a wearable device that is worn directly on the wrist. Therefore, sensors for measuring the user's pulse, blood pressure, etc. may be installed. It can accumulate data on your health and lifestyle, and can be used to help you maintain your health.

[0244] Furthermore, the above-mentioned armband type device 7300, mobile phone 7400, mobile display device 7100, A device that can be carried around, such as a belt-type device 406 and a wristwatch-type device 405 The device is equipped with a positioning system such as GPS (Global Positioning System). It is also good. Not only can the user know their current location, but it can also be used to prevent child abduction and wandering behavior. It can also be used to help respond to.

[0245] The wristwatch type device will be described in more detail with reference to FIGS. 28 and 29. FIG.

[0246] The wristwatch type device 500 shown in FIG. 28 includes a housing 501, a power storage device 502, a display unit 503, Logic board 504, antenna 505, sensor 506, microphone 507, speaker 508 and a belt portion 509. FIG. 28A shows a front view of the power storage device 502. 28(A) is a cross-sectional view of the wristwatch type device 500 taken along the dashed line AB in FIG. 28(B). The housing 501, the display unit 503, and the logic board 504 are made flexible. This allows a wristwatch-type device that can be curved along the arm.

[0247] The wristwatch type device 500 shown in FIG. 29 includes a housing 501, a power storage device 502, a display unit 503, and a display unit 504. 03, logic board 504, antenna 505, sensor 506, solar cell 510, operation button The power storage device 502 has a tongue 511 and a belt portion 509. FIG. 29(A) is a front view of the power storage device 502. 29(A) is a cross-sectional view of the wristwatch type device 500 taken along the dashed line AB in FIG. 29(B) is shown. For example, the solar cell 510 generates power, and the power storage device 502 It can be charged.

[0248] Another example of electronic equipment is shown in FIG. 30. In FIG. 30, 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.

[0249] 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.

[0250] In addition to TV broadcast reception, display devices are also used for personal computers and advertising displays. , including all display devices for displaying information.

[0251] In FIG. 30, 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. 30, 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.

[0252] 30 shows an example of a lighting device 8100 that is installed 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.

[0253] 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.

[0254] In FIG. 30, 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.

[0255] In Figure 30, 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.

[0256] In FIG. 30 , 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.

[0257] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0258] (Embodiment 5) In this embodiment, an example in which the power storage device described in Embodiment 1 is mounted on a vehicle will be described.

[0259] 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.

[0260] 31A and 31B 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

[0261] 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.

[0262] The automobile 8500 shown in FIG. 31B 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. 31(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.

[0263] 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.

[0264] Furthermore, the power storage device mounted on the vehicle can also be used as a power supply source for other purposes than the vehicle. In this case, it is possible to avoid using commercial power sources during peak power demand periods.

[0265] An example of a two-wheeled vehicle using one embodiment of the present invention will be described with reference to FIG.

[0266] The scooter 8600 shown in FIG. 32(A) has a power storage device 860 inside a side mirror 8601. The power storage device 8602 can be bent, so that the side mirror 8601 can be turned around. Even though it has a curved shape, it can be stored efficiently in a space. 8 shows an enlarged view of the side mirror 8601 as seen from the front of the vehicle. 601 includes a direction indicator light 8603. A power storage device 8602 supplies power to the direction indicator light 8603. It can supply air.

[0267] In addition, the scooter 8600 shown in FIG. 32(A) has a storage unit 8604 under the seat. The power storage device 8602 can be bent and therefore can be stored under the seat. Even if the power storage device 8604 is small, the power storage device 8602 can be bent, deformed, or folded. It can be stored in the under-seat storage 8604.

[0268] This embodiment mode can be implemented in appropriate combination with other embodiment modes. [Explanation of symbols]

[0269] 100 Electricity storage device 101 Positive electrode current collector 101a part 101b part 102 Cathode active material layer 105 Negative electrode current collector 105a part 105b part 106 Negative electrode active material layer 107 Separator 107A Separator 107B Separator 107a area 108 Electrolyte 108a Electrolyte 109a Film 109b Film 110 Exterior body 111 Positive electrode 115 Negative electrode 120 Thermocompression bonding area 120a thermocompression bonding area 120b thermocompression bonding area 121 Sealing layer 122a Thermocompression bonding area 122b Thermocompression bonding area 122c thermocompression bonding area 122d thermocompression bonding area 122e thermocompression bonding area 125 Contact surface 131 recess 132 Convex part 141 Positive lead 145 Negative lead 150 Arrows 151 Vertex 152 Vertices 156 Wiring 157 Wiring 160 convex part Type 161 Type 162 163 flat plate 170 electrode 171 Laminate 172 Laminate 175 laminate 321 Graphene 322 Cathode active material 323 Conductive additives 331 areas 332 areas 333 areas 400 Eyeglasses-type device 400a frame 400b Display section 401 Headset-type device 401a Microphone section 401b Flexible Pipe 401c Earphone section 402 Device 402a housing 402b Energy storage device 403 Device 403a housing 403b Energy storage device 405 Wristwatch-type device 405a Display section 405b Belt section 405c power storage device 406 Belt-type device 406a Belt section 406b Wireless power receiving unit 500 wristwatch-type devices 501 Case 502 Power storage device 503 Display section 504 Logic Board 505 Antenna 506 Sensors 507 Mike 508 Speaker 509 Belt section 510 Solar Cells 511 Operation button 7100 Portable display devices 7101 Housing 7102 Display section 7103 Operation button 7104 Energy storage devices 7300 Armband Device 7301 Arm 7400 mobile phone 7401 Housing 7402 Display section 7403 Operation button 7404 External connection port 7405 Speaker 7406 Microphone 7407 Electricity storage devices 7408 Lead electrode 7409 Current collector 7500 stove 7501 Energy storage devices 7511 Module 7511a Air vent 7511b External terminal 7512 main body 7512a opening 7513 Grill 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 8600 Scooter 8601 Side mirror 8602 Energy storage devices 8603 Turn signal light

Claims

1. The battery includes a positive electrode, a negative electrode, an outer casing, and an electrolyte, the positive electrode has a positive electrode current collector and a positive electrode active material layer in contact with the positive electrode current collector, the negative electrode has a negative electrode current collector and a negative electrode active material layer in contact with the negative electrode current collector, the positive electrode active material layer and the negative electrode active material layer overlap each other, the outer periphery of each of the positive electrode active material layer and the negative electrode active material layer is a closed curve, The exterior body has a film, the exterior body has a thermocompression bonding region, The exterior body is flexible, The inner periphery of the thermocompression bonding region is a closed curved line, the electrolyte, the positive electrode active material layer, and the negative electrode active material layer are located in a region surrounded by the thermocompression bonding region, the outer periphery of the positive electrode active material layer and the outer periphery of the negative electrode active material layer are substantially circular, The inner periphery of the thermocompression bonded region is substantially circular.

2. In claim 1, The film has a protrusion or a recess.

Images