Lithium-ion battery

Abstract

To provide a storage battery using a carbonaceous material and a graphene compound film having a desired ion conductivity and mechanical strength while preventing direct contact of both electrodes, or realize securing of long term reliability.SOLUTION: A lithium ion storage battery includes a positive electrode 101, a negative electrode 102, an outer sheath 107, and a separator 109 between the positive electrode and the negative electrode. One of the positive electrode and the negative electrode is wrapped by a first film. The positive electrode, the negative electrode, and the separator are stored in the outer sheath. The first film includes a first region. In the first region, the first film has a first functional group. Further, the first film includes a second region. In the second region, the first film includes a second functional group. The first functional group and the second functional group are different to each other. The first film may be a graphene compound film.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] Note that one embodiment of the present invention is not limited to the above technical fields. The technical field of one aspect relates to an article, a method, or a manufacturing method. One aspect of the present invention is a process, machine, manufacture, or composition. Therefore, the invention disclosed herein more specifically relates to The technical field of one aspect of the present invention is a semiconductor device, a display device, a liquid crystal display device, a light-emitting device, a lighting device, devices, power storage devices, storage devices, driving methods thereof, or manufacturing methods thereof, as examples. Some examples include: [Background technology]

[0003] In recent years, various storage batteries such as lithium-ion batteries, lithium-ion capacitors, and air batteries have become available. The development of energy storage devices is being actively pursued. Ion storage batteries are used in mobile phones, smartphones, laptops, and other portable devices. Information terminals, portable music players, digital cameras, and other electronic devices, as well as medical equipment and Hybrid electric vehicle (HEV), electric vehicle (EV), or plug-in hybrid vehicle (PHEV) Demand is rapidly expanding with the development of the semiconductor industry, including next-generation clean energy vehicles such as As a rechargeable energy source, it has become indispensable in today's information society. do.

[0004] The characteristics required for lithium-ion batteries are high energy density and improved cycle characteristics. These include improved safety and long-term reliability in various operating environments.

[0005] In recent years, head-mounted displays and other devices have become increasingly popular, and they are becoming increasingly popular due to their ability to adapt to the human body and its curved surfaces. A flexible display device that can be attached to a surface has been proposed. A flexible storage battery that can be attached to a curved surface and can be used in conjunction with a display device that is required.

[0006] An example of a lithium ion battery is a battery that includes at least a positive electrode, a negative electrode, and an electrolyte. The liquid is contained (Patent Document 1).

[0007] On the other hand, graphene has recently been shown to have excellent electrical properties such as high conductivity and mobility, as well as flexibility and mechanical strength. Due to its physical properties, attempts have been made to apply it to various products (Patent Document 2 to Patent Document 4).

[0008] Here, in a storage battery, which is a rechargeable power storage device sold as a product, Carbon-based materials such as graphite are used as electrodes. p 2 It has a crystal structure in which carbon atoms with hybrid orbitals are regularly arranged in a planar pattern and stacked. The lithium ions from the battery are absorbed between the layers of the stacked crystalline structure. Charging and discharging are performed.

[0009] However, carbon-based materials are useful for reducing the weight of storage batteries and are also highly safe as materials. Therefore, wider application to storage batteries should be considered. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-9418 [Patent Document 2] US Patent Application Publication No. 2011 / 0070146 [Patent Document 3] US Patent Application Publication No. 2009 / 0110627 [Patent Document 4] US Patent Application Publication No. 2007 / 0131915 Summary of the Invention [Problem to be solved by the invention]

[0011] The separator is placed between the positive electrode and the negative electrode and has the function of isolating the two electrodes. When the two poles of a storage battery are shorted, a large, uncontrollable current flows between the two poles, causing a large This may cause heat generation and lead to safety issues. Even if this does not occur, self-discharge will occur and the battery will deteriorate, impairing its function as a battery.

[0012] In addition, during the manufacturing or charging / discharging process of lithium-ion batteries, Some of the rear ions are deposited on the surface of the negative electrode and become irreversible components. These irreversible components disrupt the function of the battery. Furthermore, when lithium deposition on the negative electrode surface progresses significantly, whisker-like structures ( Depending on the properties of the separator, the structure may grow into a separator. This can pass through the holes in the capacitor and cause a short circuit between the two electrodes, which is also a problem.

[0013] Furthermore, in a flexible lithium-ion battery, the battery can be recharged according to the change in shape of the battery. Various stresses occur inside the battery. If the storage battery does not have a structure to relieve these stresses, Shear failure can easily occur at any point in the battery, causing it to lose its function as a battery.

[0014] Furthermore, if carbon-based materials, which have potentially high performance as materials, could be used in storage batteries, This makes it possible to provide a lightweight, safe, and high-quality storage battery.

[0015] In view of the above, one aspect of the present invention is to provide a lithium-ion storage battery using a carbon-based material. Another object of the present invention is to achieve a desired inductance while preventing direct contact between the electrodes of a storage battery. To provide a storage battery using a graphene compound film having ionic conductivity and mechanical strength. One of the challenges is to ensure long-term reliability.

[0016] Another object of one embodiment of the present invention is to provide a storage battery using a novel graphene compound film. Another object of one embodiment of the present invention is to provide a novel power storage device or the like. It shall be one of the following.

[0017] Another embodiment of the present invention is a storage battery that can change its shape, that is, a flexible storage battery. Another objective is to provide a new storage battery that can withstand shape changes. Another objective is to provide a novel flexible storage battery using a graphene compound film. do.

[0018] The description of these problems does not preclude the existence of other problems. It is not necessary for the present invention to solve all of these problems. The above will be made clear from the description, drawings, claims, etc. It is possible to extract other issues from the descriptions in the patent, claims, etc. [Means for solving the problem]

[0019] One embodiment of the invention disclosed in this specification has a positive electrode, a negative electrode, and an outer casing. At least one of the positive electrode and the negative electrode is at least partially enclosed in a first membrane, and the first membrane comprises: The graphene compound is contained in the positive electrode and the negative electrode, and the lithium ion It is a storage battery.

[0020] In one embodiment of the invention disclosed in the present specification, the graphene compound is a compound selected from the group consisting of graphene and matrices. The graphene is modified with atoms other than carbon or with atomic groups containing atoms other than carbon. In addition, graphene or multi-graphene is a compound having an alkyl group, an alkylene group, etc. For example, a graphene compound The thin film may contain graphene and oxygen, or may be graphene oxide.

[0021] Another embodiment of the invention disclosed in this specification is a battery having a positive electrode, a negative electrode, and an outer casing. The positive electrode and the negative electrode have a separator therebetween, and at least one of the positive electrode and the negative electrode has a first The first film has a graphene compound and is at least partially wrapped in the first film. The negative electrode and the separator are a lithium ion storage battery housed in an outer casing.

[0022] In one embodiment of the present invention, the first film has a first region, and in the first region, The lithium ion battery may be characterized in that the first membrane has a first functional group. The first film further has a second region, and in the second region, the first film has a second functional group. and wherein the first functional group is different from the second functional group. It may also be possible to use the following.

[0023] In one embodiment of the present invention, the first film has a first region, and in the first region, The first membrane may be a lithium ion battery characterized in that it has been subjected to a first modification. The first membrane further has a second region, and in the second region, the first membrane has a second modified and the first modification is different from the second modification. The first film may be a graphene oxide film. The battery may be a lithium ion battery.

[0024] Another embodiment of the invention disclosed in this specification is a battery having a positive electrode, a negative electrode, and an outer casing. The positive electrode is at least partially enclosed in the first membrane, and the negative electrode is at least partially enclosed in the second membrane. The first film has a graphene compound and the second film has a graphene compound. The positive electrode and the negative electrode are housed in an exterior body. .

[0025] Another embodiment of the invention disclosed in this specification is a battery having a positive electrode, a negative electrode, and an outer casing. The positive electrode has a separator between it and the negative electrode, and the positive electrode is at least partially enclosed in the first film. The negative electrode is at least partially enclosed in a second film, and the first film is a graphite film. a first film having a graphene compound, a second film having a graphene compound, a positive electrode, a negative electrode, a separator, and , is a lithium-ion storage battery housed in an exterior housing.

[0026] In one embodiment of the present invention, the first film has a first region, and in the first region, The lithium ion battery may be characterized in that the first membrane has a first functional group. The first film further has a second region, and in the second region, the first film has a second functional group. and wherein the first functional group is different from the second functional group. The second film may have a third region, and in the third region, the second film may have a third The lithium ion battery may be characterized by having a functional group. and in the fourth region, the second membrane has a fourth functional group and the third functional group is The lithium ion battery may be characterized by a fourth functional group different from the fourth functional group.

[0027] In one embodiment of the present invention, the first film has a first region, and in the first region, The first membrane may be a lithium ion battery characterized in that it has been subjected to a first modification. The first membrane further has a second region, and in the second region, the first membrane has a second modified and the first modification is different from the second modification. The second membrane may further have a third region, and in the third region, The second membrane is subjected to a third modification. The second film may further have a fourth region, and in the fourth region, the second film may have a fourth and the third modification is different from the fourth modification. The first film may be a graphene oxide film, and the second film may be a The lithium ion battery may be characterized by being a graphene oxide film.

[0028] In one embodiment of the present invention, the lithium ion battery may be flexible. [Effects of the Invention]

[0029] According to one embodiment of the present invention, a lithium-ion storage battery using a carbon-based material can be provided. In addition, the desired ionic conductivity and mechanical properties can be achieved while preventing direct contact between the electrodes in a storage battery. It is possible to provide a storage battery using a graphene compound film having a long-term strength. This makes it possible to ensure long-term reliability.

[0030] According to one embodiment of the present invention, a lithium-ion storage battery using the novel graphene compound film can be provided. Alternatively, one embodiment of the present invention can provide a novel power storage device or the like. It is possible.

[0031] According to one embodiment of the present invention, a storage battery having a shape-changing function, i.e., It is possible to provide a flexible storage battery. A novel graphene compound film that can withstand shape changes can be provided.

[0032] The description of these effects does not preclude the existence of other effects. The embodiment does not necessarily have to have all of these effects. , the specification, drawings, claims, etc., and It is possible to extract other effects from the claims and other descriptions. [Brief explanation of the drawings]

[0033] [Figure 1] FIG. 1 is a diagram illustrating a lithium-ion storage battery. [Figure 2] Schematic cross-sectional view of a lithium-ion battery. [Figure 3] Schematic cross-sectional view of a lithium-ion battery. [Figure 4] Schematic cross-sectional view of the internal structure of a lithium-ion battery. [Figure 5] FIG. 10 shows a negative electrode wrapped in a graphene oxide film. [Figure 6] A diagram illustrating the assembly of a lithium-ion battery. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] FIG. 1 is a diagram illustrating a coin-type storage battery. [Figure 10] FIG. 1 is a diagram illustrating a cylindrical storage battery. [Figure 11] FIG. 1 is a diagram illustrating a stacked storage battery. [Figure 12] FIG. [Figure 13] FIG. [Figure 14] 1A to 1C are diagrams illustrating a method for manufacturing a storage battery. [Figure 15] 1A and 1B are diagrams illustrating a flexible storage battery. [Figure 16] 1A and 1B are diagrams illustrating examples of storage batteries. [Figure 17] 1A and 1B are diagrams illustrating examples of storage batteries. [Figure 18] 1A and 1B are diagrams illustrating examples of storage batteries. [Figure 19] 1A and 1B are diagrams illustrating examples of storage batteries. [Figure 20] 1A and 1B are diagrams illustrating examples of storage batteries. [Figure 21] FIG. 1 is a diagram showing an application form of a storage battery. [Figure 22] FIG. 1 is a block diagram illustrating one embodiment of the present invention. [Figure 23] FIG. 1 is a conceptual diagram illustrating one embodiment of the present invention. [Figure 24] FIG. 1 is a circuit diagram illustrating one embodiment of the present invention. [Figure 25] FIG. 1 is a circuit diagram illustrating one embodiment of the present invention. [Figure 26] FIG. 1 is a conceptual diagram illustrating one embodiment of the present invention. [Figure 27] FIG. 1 is a block diagram illustrating one embodiment of the present invention. [Figure 28] 1 is a flowchart illustrating one embodiment of the present invention. [Figure 29] Schematic cross-sectional view of a lithium-ion battery. [Figure 30] Schematic cross-sectional view of an electrode and a graphene oxide film. DETAILED DESCRIPTION OF THE INVENTION

[0034] 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.

[0035] In each drawing described in this specification, the positive electrode, negative electrode, active material layer, separator, outer casing, etc. The size and thickness of each component may be exaggerated for clarity of description. Therefore, each component is not necessarily limited by its size, and the correlation between each component is not necessarily limited by its size. It is not limited to a relative size.

[0036] In addition, in this specification, ordinal numbers such as first, second, third, etc. are used for convenience. It does not indicate the order of processes or the vertical positional relationship. The "first" can be replaced with "second" or "third" as appropriate. In addition, ordinal numbers used to specify one aspect of the present invention are used in the present specification and the like. The ordinal numbers used may not match.

[0037] In addition, in the configuration of the present invention described in this specification, etc., the same parts or parts having similar functions The same reference numerals are used for the components in different drawings, and the repeated explanations will be omitted. When referring to parts with similar functions, the hatch pattern is the same and no special reference numeral is attached. There may not be.

[0038] In this specification, flexibility refers to the property that an object is flexible and can be bent. It refers to the property of an object being able to deform in response to an external force applied to it, and is different from elasticity and pre-deformation. The question is whether or not the battery can restore its original shape. A flexible storage battery can deform in response to external forces. A flexible storage battery can be used while being fixed in a deformed state. The sheet may be repeatedly deformed and used, or may be used in an undeformed state. In this specification, the inside of the exterior body refers to the exterior body of the lithium ion battery. The enclosed area includes the positive electrode, negative electrode, active material layer, separator, and other structures, as well as the electrolyte. This is the area where it is stored.

[0039] In this specification, modification refers to chemically changing the graphene oxide film to modify the graphene oxide. It refers to changing the function or properties of a membrane. It may also refer to the addition of a functional group.

[0040] Furthermore, the contents described in the embodiments of the present invention can be used in appropriate combinations. Cut.

[0041] (Embodiment 1) In this embodiment, a lithium-ion battery 100 according to one embodiment of the present invention and a manufacturing method thereof will be described. As one embodiment of the present invention, graphene oxide, which is an example of a graphene compound, will be described. This shows the case where a phen is used.

[0042] FIG. 1(A) is a diagram showing a lithium ion battery 100 according to one embodiment of the present invention. The lithium ion battery 100 includes a positive electrode 101, a negative electrode 102, and an oxide film 104 housed in an exterior body 107. The graphene film 103 and the separator 109 are included. If 103 functions as a separator, the separator 109 can be omitted. FIG. 1(B) shows the case where the separator 109 is omitted. The negative electrode 102 is electrically connected to a negative electrode lead 105. are.

[0043] FIG. 2(A) shows a lithium-ion battery 100 according to one embodiment of the present invention, which is shown in A1 of FIG. 1 is a cross-sectional view taken along line A2 and an enlarged view thereof. As shown in FIG. 2(A), the lithium ion battery 100 includes an electrolyte 106, a positive electrode 101, a negative electrode 102, and a 102, a graphene oxide film 103, and a separator 109. The lithium ion battery 100 described in this specification includes a positive electrode, a negative electrode, a graphene oxide film, and The number of the positive electrode 101 and the separator is usually one, but is not limited to this. The negative electrode 102 has a negative electrode current collector 102a, a positive electrode active material layer 101b, and a negative electrode 102c. 29(A) shows the structure of the negative electrode active material layer 102b in the B1- 29(B) is a cross-sectional view taken along the line B1-B2 in FIG. 1(B). FIG.

[0044] In the lithium ion battery 100 described in this embodiment, As shown in FIG. 1, the negative electrode 102 is wrapped in a graphene oxide film 103. However, the present invention is not limited to this, and the positive electrode 101 may be wrapped in the graphene oxide film 103. Alternatively, both the positive electrode 101 and the negative electrode 102 may be wrapped in a graphene oxide film. In the lithium ion battery 100 shown in FIG. 3(A), both the positive electrode 101 and the negative electrode 102 are Each is wrapped in a graphene oxide film.

[0045] FIG. 2B shows a lithium-ion battery 100 according to one embodiment of the present invention that does not include a separator. This shows a case where the battery is not used, and a cross-sectional view of the battery taken along the line A1-A2 in FIG. 1(B) and In the lithium ion battery 100 described in this embodiment, 2(B) shows that the negative electrode 102 is wrapped in a graphene oxide film 103, as in FIG. 2(A). However, one embodiment of the present invention is not limited thereto. Furthermore, both the positive electrode 101 and the negative electrode 102 may be enclosed in a graphene oxide film. The lithium ion battery 100 shown in FIG. Both 02 are wrapped in a graphene oxide film.

[0046] In one embodiment of the present invention, the surface of the graphene oxide film 103 is flat and has a small coefficient of friction. In this case, even if the lithium ion storage battery 100 is deformed, the lithium ion Inside the battery 100, the components can slide against each other, so stress can This reduces the risk of damage caused by the components sliding against each other, improving the durability of the battery. However, since one or both of the positive electrode 101 and the negative electrode 102 are wrapped in a graphene oxide film, Therefore, it is possible to avoid short circuit with the counter electrode. This can improve the safety of the lithium ion storage battery 100.

[0047] In a flexible stacked lithium ion storage battery 100 according to one embodiment of the present invention, When the lithium ion battery 100 is deformed, the exterior body and the internal structure are also deformed. Here, we will show the internal structure of the stacked lithium-ion battery before and after deformation. This will be explained using Figure 4.

[0048] FIG. 4(A) shows a positive electrode 101 wrapped in a graphene oxide film and a 1 is a diagram showing the internal cross-sectional structure of a lithium ion battery 100 having a negative electrode 102; A separator 109 is placed between the electrode 101 and the negative electrode 102. A cross-sectional view showing the state of the internal structure when a stacked lithium-ion battery having the structure is deformed. In FIG. 4B, the positive electrode 101 and the negative electrode 102 are made of a graphene oxide film 1 The surface of the graphene oxide film 103 is the surface of the electrode on which the active material is formed. Since the surface is smoother and has less friction than the surface of the cathode 101, the anode 102, and the separator 109, Therefore, the stress caused by the deformation of the battery between the various parts is alleviated. Therefore, damage caused by the stress is unlikely to occur. Because of its elasticity, the graphene oxide film 10 is less likely to be damaged by the stress. 3 respectively encases the positive electrode 101 and the negative electrode 102. This can prevent accidents where the two are exposed to the electrolyte and short-circuit.

[0049] Therefore, the graphene oxide film 103 that wraps the positive electrode 101 and the negative electrode 102 prevents bending. This makes it possible to realize a lithium ion storage battery that is flexible and highly durable against shocks.

[0050] Next, a method for manufacturing a storage battery according to one embodiment of the present invention will be described. Unless otherwise specified, this section mainly focuses on the lithium-ion battery shown in Figure 2(A). However, the description of this embodiment will be referred to for the lithium ion storage batteries shown in other figures. Needless to say, we can provide this.

[0051] [1. Graphene oxide film] The graphene oxide film 103 may be formed by oxidizing a graphene compound, or by using a modified acid. Graphene oxide may also be used. A sheet of graphene oxide is formed, and electrodes are placed in it. The graphene oxide film 103 may be formed by the above-mentioned method. FIGS. 5A to 5D show the steps of the method. A negative electrode 102 in which a negative electrode active material layer is formed on a negative electrode current collector in advance and a lead is attached is used. The graphene oxide sheet is folded and attached to the outer edge of the sheet with the negative electrode 102 enclosed therein. By providing a joint 108 and joining the two, a graphene oxide film 103 is formed that wraps around the negative electrode 102. At this time, the negative electrode is made of the graphene oxide film 103 at least for the purpose of leading. Therefore, a part of the lithium ion storage battery according to one embodiment of the present invention must be exposed. In the pond, the negative electrode 102 wrapped in the graphene oxide film 103 is completely wrapped. It goes without saying that the invention is not limited to being completely enclosed, but may be partially enclosed, or may be partially enclosed. In addition, the graphene oxide film 103 and the negative electrode 102 may be directly connected to each other. The graphene oxide film 103 and the negative electrode 102 may be in contact with each other, and may have any other structure between them. The negative electrode 102 may be wrapped in a sheet-like graphene oxide film 103. In this case, the joint 108 may not be provided. C) shows an example of a cross-sectional schematic diagram of a negative electrode wrapped in a graphene oxide film 103.

[0052] Another method for forming the graphene oxide film 103 is to dissolve particulate graphene oxide in a liquid dispersion medium. The electrode is immersed in the dispersion and then pulled up, removing the dispersion medium from the electrode surface. The graphene oxide film 103 may be formed by the above method. Alternatively, a casting method may be used. That is, particulate graphene oxide is dispersed in a liquid dispersion medium and then placed on an electrode. The dispersion medium is removed to form a graphene oxide film 103. It is also possible to do so.

[0053] Although an example in which the negative electrode is wrapped in sheet-like graphene oxide has been shown, In one embodiment of the present invention, one or both of the positive electrode and the negative electrode are made of an oxide. The graphene oxide film 103 is wrapped in an oxide film. In some cases, non-oxidized graphene can be used. The graphene compounds that can be used will be described in detail below.

[0054] In lithium-based batteries, repeated charging can cause lithium to deposit on the negative electrode. In particular, when lithium is deposited in a needle-like shape, the negative electrode and positive electrode are likely to short-circuit through the deposited lithium. Incidentally, the graphene oxide film 103 has a flat surface and a small coefficient of friction. By covering the negative electrode 102 with a graphene oxide film 103 having a flat surface and a small coefficient of friction, In this way, when the lithium ion battery 100 is bent and stretched, the surface of the negative electrode active material layer 102b and the The graphene oxide film 103 slides and physically removes lithium deposited on the surface of the negative electrode active material layer 102b. Therefore, a short circuit between the positive electrode 101 and the negative electrode 102 can be prevented, and the lithium ion This can prevent the performance of the lithium ion battery 100 from deteriorating. In particular, the negative electrode active material layer 102 is formed on both sides of the negative electrode current collector 102a. When the negative electrode active material layer 1 b is provided, the negative electrode active material layer 1 b is 02b The lithium deposited on the surface can be removed from both sides simultaneously. By intentionally bending and stretching the pond 100, the above effects can be further enhanced.

[0055] In addition, the graphene oxide film 103 has a flat surface and a small coefficient of friction. It can easily slide even at contact points with structures other than layer 102b. Therefore, when stress is generated in each structure due to deformation of the storage battery, each structure slides easily in response to the stress. Therefore, the storage battery is resistant to deformation. High strength.

[0056] Here, the case where the negative electrode 102 is covered with the graphene oxide film 103 will be described. However, one embodiment of the present invention is not limited thereto. For example, instead of the negative electrode 102, the positive electrode 101 may be a graphene oxide film. 3(A) and 3(B), for example, Not only the negative electrode 102 but also the positive electrode 101 may be covered with the graphene oxide film 103. good.

[0057] In addition, at least a portion of the graphene oxide film 103 may be modified. Alternatively, only a specific portion of the silicon film 103 may be modified, and the other portions may not be modified. In addition, a part of the graphene oxide film 103 may be modified differently from the other part. For example, the portion of the graphene oxide film 103 between the positive electrode and the negative electrode is lithium-ion. It is desirable that the ON can easily pass through, and other parts are short-circuited between both electrodes. Therefore, it is desirable to reliably prevent the first region and the second region of the graphene oxide film 103 from being broken down. It may be desirable for the modification state to be different between the first and second regions.

[0058] In this specification, the modified state refers to the state of modification performed on the graphene compound. In addition, the modification state is different in the two regions when the types of modification performed in the two regions are different. Not only are they different, but even when the same type of modification is performed, the strength of the modification is different. It also refers to a situation where a modification is made in one region and a modification is made in the other region. If the above does not occur, the modification state is said to be different. The two regions may differ in the types of atoms or atomic groups introduced into the graphene compounds. Therefore, even if the type of atom or atomic group to be introduced is the same, the amount introduced will differ.

[0059] The case where the modification states of the first region and the second region of the graphene oxide film 103 are different is shown in FIG. 4(C In FIG. 4C, for example, the first region 103a is a region through which lithium ions can pass. The second region 103b is modified to have high mechanical strength, so that the second region 103b is easily modified. This can be done.

[0060] The modification of the graphene compound containing graphene oxide will be described in detail later.

[0061] [2. Graphene Compounds] In one embodiment of the present invention, one or both of the positive electrode and the negative electrode are wrapped in a graphene oxide film 103. However, the graphene oxide film 103 is not limited to graphene oxide and can be made of other graphene compounds. In addition, graphene compounds other than the graphene oxide film 103 can be used. For example, the positive electrode current collector 101a, the positive electrode active material layer 101b, the negative electrode current collector 101c, and the negative electrode current collector 101d may be used in the following structure. a current collector 102a, a negative electrode active material layer 102b, a separator 109, an outer casing 107, and an electrolyte solution 106 A graphene compound can be used for at least one of the above. As will be described later, the structure and properties of graphene can be selected widely by modification. The compound can exhibit desirable properties depending on the member to which it is to be applied. Graphene compounds have high mechanical strength, so they can be used in flexible energy storage devices. The graphene compound can also be applied to each component constituting the device. do.

[0062] Graphene is a single atomic layer of carbon atoms with π bonds between the carbon atoms. When two to 100 layers of graphene are stacked, they are sometimes called multi-graphene. Graphene and multi-graphene are, for example, The length is 50 nm or more and 100 μm or less, or 800 nm or more and 50 μm or less.

[0063] In this specification and the like, a compound having graphene or multigraphene as a basic skeleton "Graphene Compound" Graphene compounds include graphene and multigraphene. .

[0064] The graphene compound will be described in detail below.

[0065] Graphene compounds, for example, are compounds in which graphene or multigraphene has atoms other than carbon, or or a compound modified with an atomic group having an atom other than carbon. Multi-graphene is modified with carbon-based atomic groups such as alkyl groups and alkylene groups. The atomic group modifying the graphene or multi-graphene may be a substituent. In this specification, modification means a group selected from the group consisting of a substituent, a functional group, a characteristic group, etc. , substitution reactions, addition reactions or other reactions to form graphene, multi-graphene, graphene phene compounds, or graphene oxide (described later), containing atoms other than carbon or This refers to the introduction of an atomic group containing carbon atoms or an atomic group mainly composed of carbon atoms.

[0066] The front and back sides of graphene are modified with different atoms or atomic groups. In addition, in multi-graphene, each layer may be modified with different atoms or atomic groups. It may be decorated.

[0067] An example of graphene modified with the above atoms or atomic groups is oxygen or oxygen-containing Examples of such graphene include graphene or multi-graphene modified with functional groups containing oxygen. Examples of functional groups include carbonyl groups such as epoxy groups and carboxyl groups, and hydroxyl groups. The graphene compound modified with oxygen or a functional group having oxygen is In this specification, graphene oxide refers to a multilayer It also includes graphene oxide.

[0068] As an example of modification of graphene oxide, silylation of graphene oxide will be explained. First, graphene oxide was placed in a container in a nitrogen atmosphere, and n-butylamine was added to the container. Add toluene (C4H9NH2) and keep at 60°C and stir for 1 hour. Then, alkyltrichlorosilane was further added as a silylating agent, and the mixture was stirred in a nitrogen atmosphere. The mixture is then stirred at 60°C for 5 hours. Next, toluene is added to the container and the mixture is filtered by suction to obtain a solid. The resulting powder is dispersed in ethanol and filtered with suction to obtain a solid powder. The resulting powder is dispersed in acetone, which is then filtered by suction to obtain a solid powder, and the liquid component is then removed. Vaporization yields silylated graphene oxide.

[0069] Although silylation was shown as an example of modification of graphene oxide, silylation The modification is not limited to oxidized graphene, but is also applicable to non-oxidized graphene. In addition, the modification described in this embodiment can also be used for graphene oxide. The present invention is not limited to the modification of graphene compounds, but may be widely applied to graphene compounds. Furthermore, the modification is not limited to silylation, and the silylation is not limited to the above-mentioned method.

[0070] Modification is not limited to the introduction of one type of atom or atomic group, but rather involves the application of multiple types of modifications to create multiple structures. Several types of atoms or atomic groups may be introduced. The modification may also include hydrogen, halogen atoms, carbon atoms, etc. The reaction may be a reaction of adding a hydrogen hydride group, an aromatic hydrocarbon group, or a heterocyclic compound group. Reactions that introduce atomic groups into amines include addition reactions and substitution reactions. Friedel-Crafts reaction, Bingel reaction, etc. A radical addition reaction may be carried out on graphene, and a cycloaddition reaction may be carried out. A ring may be formed between the graphene and the atomic group by

[0071] By introducing specific atomic groups into graphene compounds, the physical properties of graphene compounds can be changed. Therefore, by modifying the graphene compound as desired depending on the application, This allows the graphene compound to intentionally exhibit desired properties.

[0072] Next, an example of a method for producing graphene oxide will be described. Alternatively, multi-graphene can be obtained by oxidizing the graphene. Graphite oxide can be obtained by oxidizing graphite. Here, graphene oxide can be further modified with the above-mentioned atoms or atomic groups. You may do so.

[0073] The compound obtained by reducing graphene oxide is called "RGO (Reduced Graphene Oxide)." RGO is sometimes called "graphene oxide." Not all oxygen atoms are eliminated, and some oxygen atoms or atomic groups containing oxygen atoms remain bonded. For example, RGO may contain carbonyl groups such as epoxy groups, carboxyl groups, or It may have a functional group such as a hydroxyl group.

[0074] Graphene compounds are composed of multiple graphene compounds that overlap partially to form a single sheet. Such a graphene compound may be referred to as a graphene compound sheet. The graphene compound sheet has a thickness of, for example, 0.33 nm or more and 10 mm or less, Preferably, the graphene compound sheet has a region of greater than 0.34 nm and less than 10 μm. The group is an atom other than carbon, an atomic group containing atoms other than carbon, or a group containing mainly carbon such as an alkyl group. The graphene compound sheet may be modified with an atomic group such as Each of the several layers may be modified with a different atom or atomic group.

[0075] Graphene compounds are composed of not only six-membered rings made up of carbon but also five-membered rings made up of carbon and In this case, in the vicinity of the seven-membered ring or more, In this case, there may be an area through which lithium ions can pass.

[0076] Furthermore, for example, a plurality of graphene compounds may be gathered together to form a sheet shape. The graphene compound has a planar shape, which allows for surface contact.

[0077] Graphene compounds can be highly conductive even when they are thin, and surface contact can cause the graphene compounds to It is possible to increase the contact area between objects or between the graphene compound and the active material. Therefore, even if the amount per volume is small, a conductive path can be formed efficiently.

[0078] On the other hand, graphene compounds can also be used as insulators. The sheet can be used as a sheet-like insulator. For example, graphene oxide is In some cases, the insulating properties are higher than those of non-oxidized graphene compounds. Modified graphene compounds can improve their insulating properties depending on the type of atomic group used to modify them. This may be possible.

[0079] Here, in this specification and the like, the graphene compound may have a graphene precursor. A graphene precursor is a substance used to produce graphene. The ene precursor may include, for example, the above-mentioned graphene oxide or graphite oxide. .

[0080] Note that graphene containing alkali metals and graphene containing elements other than carbon, such as oxygen, In this specification and the like, graphene compounds include graphene analogues. Laphen analogues are also included.

[0081] In addition, the graphene compound in this specification and the like has atoms, atomic groups, and their interlayer bonds. In addition, the graphene compound may have atoms, atomic groups, and their ions between layers. By having ions, the physical properties of graphene compounds, such as electrical conductivity and ionic conductivity, are improved. For example, by mixing a lithium salt into a graphene compound, It can increase the ionic conductivity of phenanthracene compounds. iClO4, LiAsF6, LiBF4, LiAlCl4, LiSCN, LiBr, Li I, Li2SO4, Li2B 10 Cl 10 , Li2B 12 Cl 12 , LiCF3SO3, LiC4F9SO3, LiC(CF3SO2)3, LiC(C2F5SO2)3, LiN (CF3SO2)2, LiN(C4F9SO2)(CF3SO2), LiN(C2F5S One or more selected from the group consisting of SiO2, O2, and O2 can be used. There are cases where this happens.

[0082] Graphene compounds have excellent electrical properties, such as high conductivity, as well as high flexibility and high In addition, graphene may have excellent physical properties such as high mechanical strength. Depending on the type of modification, the compound may become an insulator by making the conductivity extremely low. In addition, the graphene compound has a planar shape. The graphene compound has low contact resistance. This allows for low surface contact.

[0083] [3. Positive electrode] The positive electrode 101 includes a positive electrode current collector 101a and a positive electrode active material layer formed on the positive electrode current collector 101a. In this embodiment, the positive electrode current collector is a sheet-shaped (or strip-shaped) positive electrode current collector. In this example, the positive electrode active material layer 101b is provided on one surface of the positive electrode active material layer 101a. However, the present invention is not limited to this. Alternatively, the positive electrode active material layer 101b may be provided on both sides of the positive electrode current collector 101a. 1b on both sides of the positive electrode current collector 101a, the capacity of the lithium ion storage battery 100 can be increased. In this embodiment, the positive electrode active material layer 101b can be made larger. However, the present invention is not limited to this and may be applied to only a part of the positive electrode current collector 101a. For example, the portion of the positive electrode current collector 101a that is in electrical contact with the positive electrode lead 104 (hereinafter The positive electrode active material layer 101b is preferably not provided on the positive electrode tab (also referred to as the "positive electrode tab"). .

[0084] The positive electrode current collector 101a may be made of stainless steel, gold, platinum, zinc, iron, copper, aluminum, or titanium. Metals such as these and their alloys have high conductivity and can be alloyed with carrier ions such as lithium. Materials that do not require high temperature resistance can be used. Also, silicon, titanium, neodymium, scandium, Aluminum alloys containing elements such as molybdenum that improve heat resistance can be used. Alternatively, it may be formed from a metal element that reacts with silicon to form silicide. Metal elements that react with silicon to form silicides include zirconium, titanium, and hafnium. Sodium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt The positive electrode current collector 101a may be in the form of a foil, a plate (sheet), a mesh, a punch, or the like. The positive electrode current collector 10 may have any shape, such as a shaped metal or an expanded metal. The thickness of the positive electrode current collector 101 is preferably 5 μm or more and 30 μm or less. An undercoat layer may be provided on the surface of a using graphite or the like.

[0085] The positive electrode active material layer 101b contains, in addition to the positive electrode active material, a binder ( The positive electrode active material layer 101b may contain a binder, a conductive additive for increasing the conductivity of the positive electrode active material layer 101b, and the like.

[0086] The positive electrode active material used in the positive electrode active material layer 101b may have an olivine-type crystal structure, a layered rock salt-type The positive electrode active material includes composite oxides having a crystalline structure of ZnO or a spinel type. For example, LiFeO2, LiCoO2, LiNiO2, LiMn2O4, V2O5, Compounds such as Cr2O5 and MnO2 are used.

[0087] 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.

[0088] 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 When mixed with (M = Co, Al, etc.), it has advantages such as suppressing the elution of manganese and suppressing the decomposition of the electrolytic solution, which is preferable.

[0089] Alternatively, a composite material (general formula LiMPO4 (M is one or more of Fe(II), Mn(II), Co(I I), Ni(II))) can be used. Representative examples of the general formula LiMPO4 include LiFePO4, LiNiPO4, LiCoPO4, LiMnPO4, LiFe a Ni b PO4, LiFe a Co b PO4, LiFe a Mn b PO4, LiNi a Co b PO4, LiNi a Mn b PO4 (a + b is 1 or less, 0 < a < 1, 0 < b < 1), LiF e c Ni d Co e PO4, LiFe c Ni d Mn e PO4, LiNi c Co d Mn e PO 4 (c + d + e is 1 or less, 0 < c < 1, 0 < d < 1, 0 < e < 1), LiFe f Ni g C o h Mn i PO4 (f + g + h + i is 1 or less, 0 < f < 1, 0 < g < 1, 0 < h < 1, 0 < i < 1), etc., lithium compounds can be used as materials.

[0090] In particular, LiFePO4 satisfies well the requirements for a cathode active material, such as safety, stability, high capacity density, high potential, and the presence of lithium ions that can be extracted during initial oxidation (charging). This is preferable because

[0091] Or, the general formula Li (2-j) MSiO4 (M is Fe(II), Mn(II), Co( A composite material such as one or more of Ni(II), Ni(II), 0≦j≦2) can be used. Formula Li (2-j) A typical example of MSiO4 is Li (2-j) FeSiO4, Li (2 -j) NiSiO4, Li (2-j) CoSiO4, Li (2-j) MnSiO4, Li (2-j) Fe k 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 (k+l is 1 or less, 0 <k<1、0<l<1)、Li (2-j) Fe m N i n Co q SiO4, Li (2-j) Fe m Ni n Mn q SiO4, Li (2-j) Ni m Co n Mn q SiO4 (m+n+q is 1 or less, 0 <m<1、0<n<1、0<q<1) , Li (2-j) Fe r Ni s Co t Mn u SiO4 (r+s+t+u is less than 1, 0 <r <1, 0 < s < 1, 0 < t < 1, 0 < u < 1), etc. Lithium compounds can be used as materials It is possible.

[0092] Also, as the positive electrode active material, A x M2(XO4)3 (A = Li, Na, Mg, M = Fe, M n, Ti, V, Nb, Al, X = S, P, Mo, W, As, Si) represented by the general formula can be used. As the NASICON-type compound, there are Fe2(MnO4) 3, Fe2(SO4)3, Li3Fe2(PO4)3, etc. Also, as the positive electrode active material 、Li2MPO4F, Li2MP2O7, Li5MO4 (M = Fe, Mn) represented by the general formula compounds, perovskite-type fluorides such as NaFeF3, FeF3, etc., metal chalcogenides (sulfides, selenides, tellurides) such as TiS2, Mo S2, etc., oxides having an inverse spinel-type crystal structure such as LiMVO4, vanadium oxide-based (V2O5, V6O 、L iV3O8, etc.), manganese oxides, organic sulfur compounds, etc. can be used as materials. 13 、L iV3O8, etc.), manganese oxides, organic sulfur compounds, etc. can be used as materials.

[0093] When the carrier ion is an alkali metal ion other than lithium ion or an alkaline earth metal ion, as the positive electrode active material, instead of lithium, an alkali metal (e.g., sodium lithium, potassium, etc.), an alkaline earth metal (e.g., calcium, strontium, barium ium, beryllium, magnesium, etc.) may be used. For example, NaFeO2 or Na2 / 3 [Fe 1 / 2 Mn 1 / 2 O2 and other sodium-containing layered oxides can be used as the positive electrode active material It can be used.

[0094] Furthermore, a combination of the above materials may be used as the positive electrode active material. A solid solution of a combination of these materials can be used as the positive electrode active material. Co 1 / 3 Mn 1 / 3 Ni 1 / 3 A solid solution of O2 and Li2MnO3 was used as the positive electrode active material. It is possible.

[0095] Although not shown, a conductive material such as a carbon layer may be provided on the surface of the positive electrode active material layer 101b. 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 101b is formed by baking the positive electrode active material. It can be formed by mixing carbohydrates such as

[0096] The average particle size of the primary particles of the granular positive electrode active material layer 101b is 50 nm or more and 100 μm or less. It is recommended to use the following.

[0097] Conductive additives include acetylene black (AB), graphite particles, and carbon Nanotubes, graphene compounds, fullerenes, etc. can be used.

[0098] The conductive additive can form an electron conductive network in the positive electrode 101. The auxiliary agent can maintain the electrical conduction path between the positive electrode active material layers 101b. By adding a conductive additive to the electrode active material layer 101b, a positive electrode active material having high electronic conductivity can be obtained. A material layer 101b can be realized.

[0099] In addition to the typical polyvinylidene fluoride (PVDF), polyimide, Polytetrafluoroethylene, polyvinyl chloride, ethylene propylene diene polymer Styrene-butadiene rubber, acrylonitrile-butadiene rubber, fluororubber, poly Vinyl acetate, polymethyl methacrylate, polyethylene, nitrocellulose, etc. This can be done.

[0100] The content of the binder relative to the total amount of the positive electrode active material layer 101b is 1 wt % or more and 10 wt % or less. is preferable, 2 wt% or more and 8 wt% or less is more preferable, and 3 wt% or more and 5 wt% or less is even more preferable. It is more preferable that the content of the conductive additive with respect to the total amount of the positive electrode active material layer 101b is 1 wt. % or more and 10 wt % or less is preferable, and 1 wt % or more and 5 wt % or less is more preferable.

[0101] When the positive electrode active material layer 101b is formed by the 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 agents, and is then applied to the positive electrode current collector 101a and dried. Just let them do it.

[0102] The positive electrode active material layer 101b may also be formed by sputtering.

[0103] In addition, when the positive electrode is wrapped with the graphene oxide film 103, the graphene oxide film that wraps the positive electrode is formed by a casting method. 30(A) to 30(C) show the oxidation graph of the negative electrode. This is a cross-sectional view of the cathode and graphene oxide film. The cross-sectional schematic diagram of the silicon film is similar.

[0104] [4. Negative electrode] The negative electrode 102 includes a negative electrode current collector 102a and a negative electrode active material layer formed on the negative electrode current collector 102a. In this embodiment, the negative electrode current collector is a sheet-shaped (or strip-shaped) negative electrode current collector. In this example, the negative electrode active material layer 102b is provided on one surface of the negative electrode active material layer 102a. However, the present invention is not limited to this. Alternatively, the negative electrode active material layer 102b may be provided on both sides of the negative electrode current collector 102a. By providing the negative electrode current collector 102b on both sides of the negative electrode current collector 102a, the capacity of the lithium ion storage battery 100 can be increased. In this embodiment, the negative electrode active material layer 102b is formed by However, the present invention is not limited to this and may be applied to only a part of the negative electrode current collector 102a. For example, the portion of the negative electrode current collector 102a that is in electrical contact with the negative electrode lead 105 ( Hereinafter, the negative electrode tab (hereinafter also referred to as "negative electrode tab") is preferably configured so that the negative electrode active material layer 102b is not provided. stomach.

[0105] The negative electrode current collector 102a may be made of metal such as stainless steel, gold, platinum, zinc, iron, copper, or titanium, or These alloys and other materials with high conductivity that do not alloy with carrier ions such as lithium are used. It can also be formed from a metal element that reacts with silicon to form silicide. Metal elements that react with silicon to form silicide include zirconium, titanium, and Tantalum, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten The negative electrode current collector 102a may be in the form of a foil, a plate (sheet), a mesh, or the like. The negative electrode may be in the form of a punched metal, an expanded metal, or the like. The current collector 102a preferably has a thickness of 5 μm or more and 30 μm or less. An undercoat layer made of graphite or the like may be provided on the surface of the conductor 102a.

[0106] The negative electrode active material layer 102b contains, in addition to the negative electrode active material, a binder ( The negative electrode active material layer 102b may contain a binder, a conductive additive for increasing the conductivity of the negative electrode active material layer 102b, and the like.

[0107] The negative electrode active material layer 102b is a layer in which lithium can be dissolved and deposited, or lithium ions can be inserted and extracted. There is no particular limitation on the material of the negative electrode active material layer 102b as long as it is a material that can be used. In addition to metals and lithium titanate, carbon-based materials and alloy-based materials, which are common in the field of energy storage, are also used. can be.

[0108] 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.

[0109] Carbon materials include graphite, easily graphitizable carbon (soft carbon), and non-graphitizable carbon (hard carbon). carbon nanotubes, graphene compounds, carbon black, etc. can be.

[0110] Graphite includes mesocarbon microbeads (MCMB), coke-based artificial graphite, and pitch. Examples of such graphite include artificial graphite such as spheroidized artificial graphite, and natural graphite such as spheroidized natural graphite.

[0111] When lithium ions are inserted between the layers of graphite (when lithium-graphite intercalation compounds are formed), ), and shows a potential as noble as that of lithium metal (0.1 to 0.3 V vs. Li / Li + This allows the lithium-ion battery to exhibit a high operating voltage. Lead has a relatively high capacity per unit volume, small volume expansion, and is inexpensive. It is preferred because it has advantages such as higher safety compared to the metal.

[0112] As a negative electrode active material, it is possible to carry out charge-discharge reactions by alloying and dealloying reactions with lithium. When the carrier ion is a lithium ion, the alloy Examples of gold-based materials include Al, Si, Ge, Sn, Pb, Sb, Bi, Ag, Zn, Examples of such elements include materials containing at least one of Cd, In, Ga, etc. The capacity is large compared to the material, and silicon in particular has a dramatically high theoretical capacity of 4200mAh / g. For this reason, it is preferable to use silicon as the negative electrode active material. Examples of gold-based materials include Mg2Si, Mg2Ge, Mg2Sn, SnS2, and V2Sn. 3, FeSn2, CoSn2, Ni3Sn2, Cu6Sn5, Ag3Sn, Ag3Sb, Ni2MnSb, CeSb3, LaSn3, La3Co2Sn7, CoSb3, InSb , SbSn, etc.

[0113] The negative electrode active material layer 102b may be made of SiO, SnO, SnO2, titanium oxide (TiO2 ), lithium titanium oxide (Li4Ti5O 12 ), lithium-graphite intercalation compound (Li x C6), niobium oxide (Nb2O5), tungsten oxide (WO2), molybdenum oxide (M Oxides such as SiO2 can be used.

[0114] The negative electrode active material layer 102b is made of a composite nitride of lithium and a transition metal, such as Li3N type Li with structure 3-x M x N (M=Co, Ni, Cu) can be used. For example, Li 2.6 Co 0.4 N3 has a large charge / discharge capacity (900mAh / g, 1890mAh / c m 3 ) and is preferred.

[0115] When a composite nitride of lithium and a transition metal is used, the negative electrode active material contains lithium ions, The positive electrode active material is a combination of materials such as V2O5 and Cr3O8 that do not contain lithium ions. It is preferable that a material containing lithium ions is used as the positive electrode active material. By first removing the lithium ions contained in the positive electrode active material, As the nitride, a complex nitride of lithium and a transition metal can be used.

[0116] Furthermore, a material that causes a conversion reaction can also be used as the negative electrode active material layer 102b. For example, cobalt oxide (CoO), nickel oxide (NiO), iron oxide (FeO), etc. Alternatively, a transition metal oxide that does not undergo an alloying reaction with lithium may be used as the negative electrode active material. Further materials that undergo oxidation reactions include Fe2O3, CuO, Cu2O, and RuO2 , oxides such as Cr2O3, CoS 0.89 , NiS, CuS and other sulfides, Zn3N2, C Nitrides such as U3N and Ge3N4, phosphides such as NiP2, FeP2, and CoP3, and FeF3 This also occurs with fluorides such as BiF3. Note that the potential of the above fluorides is high, so they are not suitable as negative electrode active materials. It may also be used as layer 102b.

[0117] When the negative electrode active material layer 102b is formed by the coating method, the negative electrode active material and the binder are mixed. A negative electrode paste (slurry) is prepared, applied to the negative electrode current collector 102a, and then dried. A conductive additive may be added to the negative electrode paste. Alternatively, the film may be formed by a tapping method.

[0118] Thereafter, a graphene oxide film 103 that wraps the negative electrode active material layer may be formed by a casting method. In this case, an example of the cross-sectional structure of the negative electrode and the graphene oxide film is shown in FIGS. 30(A) to 30(C). ) shown.

[0119] A graphene compound may be formed on the surface of the negative electrode active material layer 102b. When the electrode active material layer 102b is made of silicon, the absorption of carrier ions during charge / discharge cycles is Since the volume change due to the storage and release is large, the negative electrode current collector 102a and the negative electrode active material layer 102b The adhesion between the negative electrode and the negative electrode decreases, and the battery characteristics deteriorate during charging and discharging. When a graphene compound is formed on the surface of the electrode active material layer 102b, the following occurs during charge-discharge cycles: Even if the volume of silicon changes, the density between the negative electrode current collector 102a and the negative electrode active material layer 102b remains constant. This is preferable because it can suppress the decrease in adhesion and reduce the deterioration of battery characteristics.

[0120] Furthermore, a coating of oxide or the like may be formed on the surface of the negative electrode active material layer 102b. The coating formed by the decomposition of the electrolyte releases the amount of charge consumed during its formation. In contrast, a film of oxide or the like is formed on the negative electrode active material in advance, and irreversible capacity is formed. By providing the electrode on the surface of the porous layer 102b, it is possible to suppress or prevent the occurrence of irreversible capacitance. Cut.

[0121] The coating that coats the negative electrode active material layer 102b may contain niobium, titanium, vanadium, tantalum, or the like. Ta, tungsten, zirconium, molybdenum, hafnium, chromium, aluminum or silicon oxide film, or a film containing one of these elements and lithium Such a coating is not susceptible to damage caused by the decomposition products of conventional electrolytes. This film is sufficiently dense compared to the coating formed on the outermost surface.

[0122] 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.

[0123] The coating that covers the negative electrode active material layer 102b can be formed by, for example, a sol-gel method. The sol-gel method is a method in which a solution of metal alkoxides or metal salts is subjected to a hydrolysis reaction. This method involves forming a gel that has lost its fluidity through a polycondensation reaction, and then baking this gel to form a thin film. The sol-gel method is a method for forming thin films from a liquid phase, so the raw materials must be homogenized at the molecular level. Therefore, the raw material of the metal oxide film at the solvent stage can be mixed with a negative electrode active material such as graphite. By adding a binder, the active material can be easily dispersed in the gel. A coating can be formed on the surface of the negative electrode active material layer 102b. By using the coating, This can prevent the capacity of the storage battery from decreasing.

[0124] [5. Electrolyte] The solvent of the electrolyte 106 used in the lithium ion battery 100 is an aprotic organic solvent. Preferred solvents are ethylene carbonate (EC), propylene carbonate (PC), etc. ), butylene carbonate, chloroethylene carbonate, vinylene carbonate, γ- Butyrolactone, γ-valerolactone, dimethyl carbonate (DMC), diethyl carbonate Decanoate (DEC), ethyl methyl carbonate (EMC), methyl formate, methyl acetate, Methyl butyrate, 1,3-dioxane, 1,4-dioxane, dimethoxyethane (DME), Dimethyl sulfoxide, diethyl ether, methyl diglyme, acetonitrile, benzo nitrile, tetrahydrofuran, sulfolane, sultone, or two of these One or more species can be used in any combination and ratio.

[0125] In addition, by using a polymer material that gels as a solvent for the electrolyte, safety against leakage etc. is improved. The safety of the secondary battery is improved. In addition, the secondary battery can be made thinner and lighter. Typical examples of materials include silicone gel, acrylic gel, acrylonitrile gel, and polyethylene gel. Polypropylene oxide gel, polypropylene oxide gel, fluorine polymer gel, etc. be.

[0126] In addition, a flame-retardant and non-volatile ionic liquid (room-temperature molten salt) was used as the solvent for the electrolyte. Or by using multiple batteries, even if the internal temperature rises due to an internal short circuit or overcharging of the battery, This can prevent the battery from exploding or catching fire.

[0127] In addition, when lithium ions are used as a carrier, the electrolyte to be dissolved in the solvent is , such as LiPF6, LiClO4, LiAsF6, LiBF4, LiAlCl4, Li SCN, LiBr, LiI, Li2SO4, Li2B 10 Cl 10 , Li2B 12 Cl1 2, LiCF3SO3, LiC4F9SO3, LiC(CF3SO2)3, LiC(C2 F5SO2)3, LiN(CF3SO2)2, LiN(C4F9SO2)(CF3SO2 ), LiN(C2F5SO2)2, or two or more of these lithium salts Any combination and ratio may be used.

[0128] In addition, the electrolyte used in the storage battery does not contain granular waste or elements other than the constituent elements of the electrolyte (hereinafter simply referred to as It is preferable to use a highly purified electrolyte solution with a low content of impurities. Specifically, the weight ratio of impurities to the electrolyte is 1% or less, preferably 0.1% or less, more preferably 1% or less. It is more preferable that the content of vinylene carbonate in the electrolyte is 0.01% or less. Additives such as acetone may also be added.

[0129] [6. Exterior body] There are various types of secondary battery structures. In this embodiment, the outer casing 107 is formed The film for forming the exterior body 107 is a metal film (aluminum). aluminum, stainless steel, nickel steel, etc.), plastic film made of organic materials, Hybrid materials that contain organic materials (such as organic resins and fibers) and inorganic materials (such as ceramics) Material film, carbon-containing inorganic film (carbon film, graphite film, etc.) A single layer film selected from the above or a laminated film made up of a plurality of these metal films is used. is easy to emboss, and when recesses or protrusions are formed by embossing, Since the surface area of ​​the exterior body 107 that comes into contact with the heat source increases, the heat dissipation effect is excellent.

[0130] In addition, when the shape of the lithium ion storage battery 100 is changed by applying an external force, When external bending stress is applied to the exterior body 107 of the lithium-ion storage battery 100, a part of the exterior body 107 If a recess or protrusion is formed on the surface of the exterior body 107, deformation or partial destruction may occur. By doing so, it is possible to alleviate the strain caused by the stress applied to the exterior body 107. This makes it possible to improve the reliability of the lithium ion battery 100. The deformation is a measure of the displacement of a material point within an object relative to the reference (initial) length of the object. By forming recesses or protrusions on the surface of the exterior body 107, it is possible to apply a force from outside the storage battery. Therefore, the influence of distortion caused by the addition of a certain amount of stress can be suppressed within an acceptable range. It can provide a good battery.

[0131] [7. Separator] In one embodiment of the present invention, for example, as shown in Figs. 1(A), 2(A) and 3(A), A separator 109 may be provided between the positive electrode 101 and the negative electrode 102 .

[0132] The separator 109 is made of paper, nonwoven fabric, glass fiber, nylon (polyamide), vinyl, or the like. Nilon (also known as Vinalon) (polyvinyl alcohol fiber), polyester, acrylic Synthetic fibers such as polyolefin and polyurethane may be used. Phenol compounds can also be used, but it is necessary to select materials that do not dissolve in the electrolyte.

[0133] More specifically, the separator 109 may be made of a material such as a fluorine-based polymer or polyethylene. Polyethers such as propylene oxide and polypropylene oxide, polyethylene, polypropylene Polyolefins such as polyacrylonitrile, polyvinylidene chloride, polymethyl methacrylate acrylate, polymethyl acrylate, polyvinyl alcohol, polymethacrylonitrile, poly Polyvinyl acetate, polyvinylpyrrolidone, polyethyleneimine, polybutadiene, poly styrene, polyisoprene, polyurethane polymers and their derivatives, cellulose, One material selected from paper and nonwoven fabric can be used alone, or two or more materials can be used in combination.

[0134] However, when the graphene oxide film 103 can exhibit the function as a separator, Although it is not necessary to provide the separator 109 separately, one embodiment of the present invention is not limited thereto. By separately providing the separator 109, the lithium-ion storage battery according to one embodiment of the present invention can be may be able to drive more safely.

[0135] [8. Battery assembly and aging] Next, the above-mentioned components are combined and sealed in the exterior body 107, thereby forming the device shown in FIGS. As shown in FIG. 3, a positive electrode 101, a negative electrode 102, and a graphene oxide film 103 are stacked. The battery is sealed together with the electrolyte solution 106 by the exterior body 107. The process of storing each component in the container is shown in Fig. 6(A) and Fig. 6(B). When a separator 109 is used, it is placed between the positive electrode 101 and the negative electrode 102 .

[0136] The shape of the sealing part may be a curve, a wavy line, an arc, or the like, according to the shape of the internal structure of the storage battery. The shape of the sealing portion may be such that it conforms to the shape of the internal structure. If the shape is different, deformation of the battery may cause different stresses to be applied to the exterior body and the internal structure. However, even if there is a problem, it is possible to prevent the internal structure from sliding unintentionally. The shape of the stopper is not limited to this.

[0137] Next, the aging process is performed. First, the ambient temperature is kept at, for example, room temperature, and the film is aged at a constant low rate. Next, the gas generated in the area inside the exterior body due to charging is released to the outside. Next, charge the battery at a rate higher than the initial charge.

[0138] Then, store it in a slightly higher temperature environment for a long period of time, for example, in an environment of 40°C or higher for 24 hours or more. For example, it can be stored in an environment of 70°C or higher. It can also be stored in an environment of 80°C or higher. It may be stored in an environment of 90°C or higher. It may also be stored in an environment of 100°C or higher. It can also be stored for 36 hours or more. It can also be stored for 48 hours or more. It is acceptable to store it for more than 72 hours. It is sufficient to increase the environmental temperature within a non-hazardous range. This is a safe aging process, which may contribute to suppressing deterioration of the storage battery. A sufficient aging process can be achieved by extending the storage time within this range. This may also contribute to suppressing deterioration of the storage battery.

[0139] After long-term storage in a slightly high temperature environment, the gas generated in the area inside the exterior body is released again. Furthermore, discharge the battery at a rate of 0.2C in a room temperature environment, charge it at the same rate, and then charge it again at the same rate. After discharging at the same rate, the battery is charged again at the same rate. The aging process is completed.

[0140] In this manner, the lithium ion storage battery according to the present invention can be manufactured.

[0141] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0142] In this specification, etc., in a drawing or text that describes one embodiment, If at least one specific example is described, it is not possible to derive a generic concept of that specific example. This will be easily understood by those skilled in the art. When at least one specific example is described in a figure or text, the general outline of that specific example is The invention is also disclosed as an aspect of the invention and may constitute an aspect of the invention. Therefore, one aspect of the invention can be said to be clear.

[0143] In this specification, at least the contents shown in the drawings (or even a part of the drawings) This is disclosed as one aspect of the invention and can constitute one aspect of the invention. Therefore, if something is shown in a diagram, it is not necessarily stated in words. However, the content is disclosed as one aspect of the invention and constitutes one aspect of the invention. Similarly, even if a part of the drawings is taken out, it can be regarded as one embodiment of the invention. This is disclosed as an embodiment of the present invention. It can be said that one aspect of the invention is clear.

[0144] Note that one embodiment of the present invention has been described in this embodiment. However, the present invention is not limited to these. That is, in this and other embodiments, various aspects of the invention are described. Therefore, one embodiment of the present invention is not limited to a specific embodiment. An example in which the present invention is applied to a lithium ion battery has been shown. In some cases, or depending on the circumstances, one aspect of the present invention is to Batteries, lead-acid batteries, lithium-ion polymer secondary batteries, nickel-metal hydride batteries, nickel- Cadmium storage battery, nickel-iron storage battery, nickel-zinc storage battery, silver oxide-zinc storage battery, Solid-state batteries, air batteries, primary batteries, capacitors, or electric double layer capacitors, ultra It can be applied to capacitors, super capacitors, lithium ion capacitors, etc. For example, in some cases or depending on the circumstances, one aspect of the present invention is to The laphene film 103 may not be applied.

[0145] (Embodiment 2) In this embodiment, a flexible lithium ion battery will be described.

[0146] <Flexible storage battery> When a flexible material is selected from the materials of each member shown in this embodiment, It is possible to fabricate a flexible lithium-ion battery. There has been active research and development into flexible batteries for use in such devices. This has created a demand for storage batteries.

[0147] The deformation of the storage battery will be explained using Figure 7. Two films are used as the exterior body, and the electrodes and When the storage battery sandwiching the battery material 1805 such as the electrolyte is bent, the center of curvature 18 The radius of curvature 1802 of the film 1801 on the side closer to 00 is the radius of curvature 1802 on the side farther from the center of curvature 1800. The radius of curvature of the film 1803 is smaller than the radius of curvature of the film 1804 (FIG. 7(A)). If the cross section is arc-shaped, compressive stress is applied to the surface of the film close to the center of curvature 1800, The surface of the film far from the center of curvature 1800 is subjected to tensile stress (Figure 7(B)).

[0148] When a flexible lithium-ion battery is deformed, a large stress is applied to the exterior. When a pattern consisting of recesses or protrusions is formed on the surface of the exterior body, the pressure generated by the deformation of the storage battery is reduced. Even if compressive stress or tensile stress is applied, the effects of strain can be suppressed. Therefore, the battery will deform until the radius of curvature of the exterior body on the side closest to the center of curvature becomes 50 mm or less. The battery may be deformed to a size of 30 mm or less. do.

[0149] The radius of curvature of a surface will be explained using the drawings. In FIG. 8(A), a curved surface 1700 is cut. In the plane 1701, a part of the curve 1702 included in the curved surface 1700 is approximated to an arc of a circle. The radius of the circle is the radius of curvature 1703, and the center of the circle is the center of curvature 1704. FIG. 8(B) shows a top view of the curved surface 1700. FIG. 8(C) shows the curved surface 1700 cut by a plane 1701. When cutting a curved surface with a plane, the angle of the plane to the curved surface and the cutting position are important. The radius of curvature of the curve that appears in the cross section will differ depending on the position. The smaller radius of curvature is taken as the radius of curvature of the surface.

[0150] The cross-sectional shape of the storage battery is not limited to a simple arc shape, and may be a shape having a partial arc. For example, the shape shown in FIG. 7(C), a wave shape (FIG. 7(D)), an S-shape, etc. If the curved surface of the storage battery has a shape with multiple centers of curvature, The two exterior bodies are connected at the surface with the smallest curvature radius among the curvature radii at each center. The radius of curvature of the outer casing closest to the center of curvature can be deformed to 50 mm, and In some cases, the battery can deform up to an additional 30 mm.

[0151] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0152] (Embodiment 3) In this embodiment, a structure of a storage battery according to one embodiment of the present invention will be described with reference to FIGS. 9 to 11. and explain.

[0153] <Coin-type storage battery> FIG. 9(A) is an external view of a coin-type (single-layer flat) storage battery, and FIG. 9(B) is a cross-sectional view of the battery. FIG.

[0154] The coin-type storage battery 300 has a positive electrode can 301 that also serves as a positive electrode terminal and a negative electrode can 302 that also serves as a negative electrode terminal. 02 is insulated and sealed by a gasket 303 made of polypropylene or the like. The electrode 304 is composed of a positive electrode current collector 305 and a positive electrode active material layer 306 provided in contact with the positive electrode current collector. The positive electrode active material layer 306 is formed by the positive electrode active material and a layer that enhances the adhesion of the positive electrode active material. and a conductive additive for increasing the conductivity of the positive electrode active material layer. Good too.

[0155] The negative electrode 307 includes a negative electrode current collector 308 and a negative electrode active material layer provided in contact with the negative electrode current collector. The negative electrode active material layer 309 is formed by the negative electrode active material and the adhesiveness of the negative electrode active material. binders to enhance the conductivity of the negative electrode active material layer, and conductive additives to enhance the conductivity of the negative electrode active material layer. In addition, a separator may be provided between the positive electrode active material layer 306 and the negative electrode active material layer 309. The positive electrode 304 and the negative electrode 307 are connected to each other via a positive electrode 304 and a negative electrode 307. Both sides are wrapped in a graphene oxide film (not shown).

[0156] The materials shown in the first embodiment can be used for each component.

[0157] The positive electrode can 301 and the negative electrode can 302 are made of nickel, titanium, or the like, which is corrosion-resistant to the electrolyte. These metals, or their alloys or alloys of these with other metals (such as stainless steel) are used. In addition, it is preferable to coat the electrode with nickel or the like to prevent corrosion by the electrolyte. The positive electrode can 301 is electrically connected to the positive electrode 304, and the negative electrode can 302 is electrically connected to the negative electrode 307. To be continued.

[0158] The negative electrode 307, the positive electrode 304, and the separator 310 are impregnated with an electrolyte, and as shown in FIG. As shown, the positive electrode can 301 is placed downwards, and the positive electrode 304, separator 310, negative electrode 307, and negative electrode The cans 302 are stacked in this order, and the positive electrode can 301 and the negative electrode can 302 are secured together with a gasket 303 interposed therebetween. The coin-shaped storage battery 300 is manufactured by crimping.

[0159] Here, the flow of current during charging of a storage battery will be explained using FIG. 9(C). When a battery is considered as a closed circuit, the movement of lithium ions and the flow of current are in the same direction. In addition, in a lithium-based battery, the anode (positive electrode) and cathode (negative electrode) change during charging and discharging. ) are switched, and the oxidation reaction and reduction reaction are switched. The electrode with the lower reaction potential is called the positive electrode, and the electrode with the lower reaction potential is called the negative electrode. Whether charging, discharging, or applying a reverse pulse current, the charging current Even when electricity flows through the positive electrode, it is called the "positive electrode" or "+ electrode (plus electrode)" and the negative electrode is called the "negative electrode" " or "-pole (negative pole)". When the terms anode (positive electrode) and cathode (negative electrode) are used, the relationship is reversed during charging and discharging. This can lead to confusion. Therefore, the anode and cathode are The term "anode" or "cathode" is not used in this specification. When using the term cathode, specify whether it is charging or discharging, and ) or negative pole (minus pole).

[0160] A charger is connected to the two terminals shown in Figure 9(C) to charge the storage battery 400. As the charging of the battery 400 progresses, the potential difference between the electrodes increases. The current flows from the external terminal (tab electrode) to the positive electrode 402 and enters the electrolyte 406 in the storage battery 400. and the separator 408 in the electrolyte 406 from the positive electrode 402 to the negative electrode 404 . The direction of the current flowing from the negative electrode to the external terminal (tab electrode) of the storage battery 400 is called the positive direction. In other words, the direction of the current is the same as the direction of the charging current.

[0161] <Cylindrical storage battery> Next, an example of a cylindrical storage battery will be described with reference to FIG. 10. As shown in FIG. 10(A), the battery lid 601 has a positive electrode cap (battery lid) on the top surface, and The battery can (external can) 602 is provided on the bottom surface. It is insulated from O2 by a gasket (insulating packing) 610.

[0162] Fig. 10(B) is a schematic diagram showing the cross section of a cylindrical storage battery. Inside 602, a strip-shaped positive electrode 604 and a negative electrode 606 are wound with a separator 605 sandwiched between them. Although not shown, the battery element is wound around a center pin. The battery can 602 is closed at one end and open at the other. Metals such as nickel and titanium that are corrosion-resistant to the electrolyte, or alloys of these metals or alloys of these metals An alloy of the metal with other metals (for example, stainless steel, etc.) can be used. To prevent corrosion due to the above, it is preferable to coat the inside of the battery can 602 with nickel or the like. The battery element, in which the positive electrode, negative electrode, and separator are wound, is sandwiched between a pair of opposing insulating plates 608, The battery element is sandwiched between the battery can 602 and the non-aqueous electrolyte 609. The non-aqueous electrolyte (not shown) is the same as that used in coin-type batteries. You can be there.

[0163] The positive electrode 604 and the negative electrode 606 are manufactured in the same manner as the positive electrode and the negative electrode of the coin-type storage battery described above. However, since the positive and negative electrodes used in cylindrical storage batteries are wound, active materials are placed on both sides of the current collector. Although not shown, the positive electrode 604 and the negative electrode 606 are different in that they form a solid film. Both sides are wrapped in a graphene oxide film. The graphene oxide film is the internal structure of the battery. When winding objects, it reduces friction between the structures and relieves stress. A positive electrode terminal (positive electrode tab electrode) 603 is connected to the electrode 604, and a negative electrode terminal (negative electrode tab electrode) is connected to the negative electrode 606. The positive electrode terminal 603 and the negative electrode terminal 607 are both made of aluminum. The positive terminal 603 is connected to a safety valve mechanism 612, and the negative terminal 603 is connected to a metal material such as aluminum. The electrode terminals 607 are resistance welded to the bottom of the battery can 602. The safety valve mechanism 612 is C element (Positive Temperature Coefficient) 611 The safety valve mechanism 612 is electrically connected to the positive electrode cap 601 via the When the increase in the positive electrode cap 601 exceeds a predetermined threshold, the electrical connection between the positive electrode cap 601 and the positive electrode 604 is broken. The PTC element 611 increases its resistance when the temperature rises. It is a thermal resistor element that limits the amount of current by increasing the resistance, preventing abnormal heat generation. The PTC element uses semiconducting ceramics such as barium titanate (BaTiO3). It is possible.

[0164] <Stacked storage battery> Next, an example of a stacked type storage battery will be described with reference to FIG. If the pond is configured to have flexibility, it can be used as an electronic device having at least a flexible portion. If mounted in a container, the battery can also be bent to match the deformation of the electronic device.

[0165] The stacked type storage battery 500 shown in FIG. 11(A) includes a positive electrode current collector 501 and a positive electrode active material layer 50 2, and a negative electrode 50 having a negative electrode current collector 504 and a negative electrode active material layer 505. 6, a separator 507, an electrolyte 508, and an exterior body 509. A separator 507 is placed between a positive electrode 503 and a negative electrode 506 provided inside. The exterior body 509 is filled with an electrolyte 508. 1 can be used. However, at least one of the positive electrode 503 and the negative electrode 506 is wrapped in a graphene oxide film. do.

[0166] In the stacked type storage battery 500 shown in FIG. 11(A), a positive electrode current collector 501 and a negative electrode current collector 504 also serves as a terminal for electrical contact with the outside. The negative electrode current collector 501 and a part of the negative electrode current collector 504 are arranged so as to be exposed to the outside from the outer casing 509. In addition, the positive electrode current collector 501 and the negative electrode current collector 504 may be exposed to the outside from the outer casing 509. Instead, a tab electrode is used to connect the tab electrode to the positive electrode current collector 501 or the negative electrode current collector 504. The tab electrode may be exposed to the outside by ultrasonic bonding.

[0167] In the stacked type storage battery 500, the exterior body 509 is made of, for example, polyethylene, polypropylene, Aluminum is coated on a film made of a material such as polyethylene terephthalate, polycarbonate, ionomer, or polyamide. A thin metal film made of highly flexible material such as aluminum, stainless steel, copper, or nickel is applied to the surface of the thin metal film. The outer surface of the exterior body is covered with an insulating synthetic resin film such as polyamide resin or polyester resin. A laminate film having a three-layer structure can be used.

[0168] An example of the cross-sectional structure of a stacked type storage battery 500 is shown in FIG. For simplicity, an example consisting of two electrodes is shown, but in reality, it is composed of a plurality of electrodes.

[0169] In FIG. 11(B), as an example, the number of electrodes is set to 16. In FIG. 11(B), the storage battery 500 has eight negative electrodes 506 and one positive electrode 50 3 shows a structure of 8 pieces, totaling 16 pieces. Note that Figure 11(B) shows a cross section of the negative electrode extraction part. The figure also shows eight negative electrode current collectors 504 ultrasonically bonded together. The number of electrodes is not limited to six, and may be more or less. In addition, when the number of electrodes is small, the battery can be made thinner. This allows the storage battery to have excellent flexibility.

[0170] An example of an external view of a stacked type storage battery 500 is shown in FIGS. 12 and 13. 13 is a positive electrode 503, a negative electrode 506, a separator 507, an outer casing 509, and a graphene oxide film. 531, a positive electrode tab electrode 510, and a negative electrode tab electrode 511. In the case of the battery, a plurality of negative electrodes 506 and a plurality of positive electrodes 503 are used. In this example, each part is illustrated on one sheet to avoid clutter.

[0171] 14(A) shows an external view of the positive electrode 503 and the negative electrode 506. The positive electrode 503 is connected to the positive electrode current collector 50 1, and the positive electrode active material layer 502 is formed on the surface of the positive electrode current collector 501. 503 has an area where the positive electrode current collector 501 is partially exposed. This area is connected to the tab electrode. The negative electrode 506 is a negative electrode collection area. The negative electrode active material layer 505 is formed on the surface of the negative electrode current collector 504. The negative electrode 506 also has a region where the negative electrode current collector 504 is partially exposed, i.e., a tab region. The area and shape of the tab regions of the positive and negative electrodes are not limited to the example shown in FIG. At least one of the negative electrode 506 and the positive electrode 503 is wrapped in graphene oxide.

[0172] <<Method for manufacturing stacked storage batteries>> Here, an example of a method for manufacturing the stacked type storage battery shown in the external view of FIG. 12 will be described with reference to FIG. 14(B), This will be explained using (C).

[0173] First, the negative electrode 506, the separator 507, and the positive electrode 503 are stacked. The figure shows five negative electrodes 506, separators 507, and positive electrodes 503. Next, the bonding of the tab regions of the positive electrode 503 and the bonding of the tabs of the positive electrode on the outermost surface are shown. The positive electrode tab electrode 510 is bonded to the region. For example, ultrasonic bonding or the like may be used for bonding. Similarly, the tab regions of the negative electrodes 506 are joined together, and the negative electrode tab is attached to the tab region of the negative electrode on the outermost surface. The electrode 511 is bonded. In this case, the negative electrode 506 is wrapped in a graphene oxide film 531. are.

[0174] Next, the negative electrode 506 , the separator 507 and the positive electrode 503 are placed on the exterior body 509 .

[0175] Next, as shown in FIG. 14(C), the exterior body 509 is folded at the portion indicated by the broken line. Thereafter, the outer periphery of the exterior body 509 is bonded. For example, thermocompression bonding may be used for bonding. , and a part (or one side) of the outer casing 509 so that the electrolyte 508 can be poured therein later. An area that is not bonded (hereinafter referred to as an inlet) is provided.

[0176] Next, the electrolyte 508 is introduced into the inside of the exterior body 509 through an inlet provided in the exterior body 509. The introduction of the electrolytic solution 508 is preferably carried out under a reduced pressure atmosphere or an inert gas atmosphere. Finally, the inlet is joined. In this way, the stacked type storage battery is Pond 500 can be created.

[0177] In this embodiment, the storage batteries are of coin type, stacked type, and cylindrical type. However, other types of batteries such as sealed batteries and rectangular batteries can also be used. In addition, a structure in which a positive electrode, a negative electrode, and a separator are stacked in multiple layers, a structure in which a positive electrode, a negative electrode, and a separator are stacked in multiple layers, It may also have a wound structure.

[0178] An example of mounting a flexible storage battery in an electronic device is shown in Figure 15. As an electronic device to which a storage battery having such a configuration is applied, for example, a television device (television, (also called television receivers), computer monitors, digital cameras, digital digital video cameras, digital photo frames, mobile phones (also called mobile phones or mobile phone devices) (c), portable game machines, personal digital assistants, audio playback devices, large game machines such as pachinko machines, etc. Examples include:

[0179] In addition, flexible storage batteries can be installed on the interior or exterior walls of houses and buildings, or on the exterior walls of automobiles. It can also be installed along curved interior or exterior surfaces.

[0180] FIG. 15A 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 Pond 7407.

[0181] FIG. 15B shows the mobile phone 7400 in a bent state. When the battery 7 is deformed by an external force and curved, 407 is also bent. At this time, the state of the bent storage battery 7407 is as shown in FIG. 15(C). The storage battery 7407 is a stacked type storage battery.

[0182] FIG. 15(D) shows an example of a bangle-type display device. The portable display device 7100 includes: The device includes a housing 7101, a display unit 7102, operation buttons 7103, and a storage battery 7104. FIG. 15(E) shows the state of the bent storage battery 7104.

[0183] <Example of storage battery structure> An example of the structure of the storage battery will be described with reference to Figs. 16 to 20. 16 to 20, the positive or negative electrode of the storage battery is wrapped in a graphene oxide film.

[0184] 16(A) and 16(B) are diagrams showing the external appearance of the storage battery. 900 and a storage battery 913. A label 910 is attached to the storage battery 913. Furthermore, as shown in FIG. 16(B), the storage battery has a terminal 951, a terminal 952, and an antenna. 914 and an antenna 915.

[0185] The circuit board 900 has a terminal 911 and a circuit 912. The terminal 911 is connected to a terminal 951. , terminal 952, antenna 914, antenna 915, and circuit 912. A plurality of terminals 911 are provided, and each of the plurality of terminals 911 is used as a control signal input terminal, a power supply terminal, etc. may also be used.

[0186] The circuit 912 may be provided on the back surface of the circuit board 900. The antenna 915 is not limited to a coil shape, but may be, for example, a wire shape or a plate shape. Planar antenna, aperture antenna, traveling wave antenna, EH antenna, magnetic field antenna, dielectric Alternatively, antenna 914 or antenna 915 may be used. The flat conductor may function as one of the conductors for electric field coupling. In other words, the capacitor has two conductors, one of which is an annulus. The antenna 914 or the antenna 915 may be activated. Instead, power can be exchanged using an electric field.

[0187] The line width of antenna 914 is preferably larger than the line width of antenna 915. This allows the amount of power received by the antenna 914 to be increased.

[0188] The battery has a layer 916 between the antenna 914 and the antenna 915 and the battery 913. The layer 916 has a function of preventing the influence of the storage battery 913 on the electromagnetic field, for example. The layer 916 may be made of, for example, a magnetic material.

[0189] The structure of the storage battery is not limited to that shown in FIG.

[0190] For example, as shown in FIGS. 17(A-1) and 17(A-2), In the storage battery 913 shown in (B), an antenna may be provided on each of a pair of opposing surfaces. FIG. 17(A-1) is an external view of the pair of surfaces as seen from one side. A-2) is an external view seen from the other side of the pair of surfaces. The same parts as those of the storage battery shown in Fig. 16(A) and Fig. 16(B) are shown in Fig. 16(A) and Fig. 16(B). The description of the storage battery can be used as appropriate.

[0191] As shown in FIG. 17(A-1), a layer 916 is sandwiched between one of the pair of surfaces of a storage battery 913. 17(A-2), a retainer 914 is provided on the other side of the pair of surfaces of the storage battery 913. An antenna 915 is provided on the other side of a layer 917. The layer 917 is, for example, a storage battery 913. The layer 917 has a function of preventing the influence of the electromagnetic field generated by the magnetic field. You can use your body.

[0192] By adopting the above structure, the size of both the antenna 914 and the antenna 915 can be increased. It is possible.

[0193] Alternatively, as shown in Figs. 17(B-1) and 17(B-2), In the storage battery 913 shown in B), separate antennas may be provided on each of the pair of opposing surfaces. FIG. 17(B-1) is an external view of one of the pair of surfaces as viewed from the side. (B-2) is an external view seen from the other side of the pair of surfaces. The same parts as the storage battery shown in Fig. 16(A) and Fig. 16(B) are shown in Fig. 16(A) and Fig. 16(B). The description of the storage battery shown in the accompanying drawings can be used as appropriate.

[0194] As shown in FIG. 17(B-1), a layer 916 is sandwiched between one of the pair of surfaces of the storage battery 913. 17(B-2), a storage battery 91 An antenna 918 is provided on the other of the pair of surfaces of the substrate 3, sandwiching a layer 917 therebetween. For example, the antenna 918 has a function of performing data communication with an external device. For example, antennas having shapes applicable to the antennas 914 and 915 can be applied. As a communication method between the storage battery and other devices via the antenna 918, NFC or the like can be used. It is possible to apply a response method that can be used between the storage battery and other devices, such as .

[0195] Alternatively, as shown in FIG. 18(A), the storage battery 913 shown in FIG. 16(A) and FIG. 16(B) A display device 920 may be provided. The display device 920 is connected to the terminal 911 via the terminal 919. The label 910 is not necessarily provided in the area where the display device 920 is provided. 16(A) and 16(B) are the same as those in the storage battery shown in FIG. The explanation of the storage battery shown in FIG. 6(A) and FIG. 16(B) can be used as appropriate.

[0196] The display device 920 displays, for example, an image indicating whether charging is in progress or not, an image indicating the amount of stored power, etc. The display device 920 may be, for example, an electronic paper, a liquid crystal display, an electrophotographic display, or the like. For example, an electroluminescence (EL) display device can be used. By using the par, the power consumption of the display device 920 can be reduced.

[0197] 18(B), the storage battery 913 shown in FIG. 16(A) and FIG. 16(B) A sensor 921 may be provided. The sensor 921 is electrically connected to the terminal 911 via a terminal 922. The same parts as the storage battery shown in Fig. 16(A) and Fig. 16(B) are connected to The description of the storage battery shown in FIGS. 16(A) and 16(B) can be used as appropriate.

[0198] The sensor 921 may be, for example, a sensor for detecting displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, etc. , liquid, magnetic, temperature, chemical, sound, time, hardness, electric field, current, voltage, power, radiation, flow It is sufficient if it has the function of measuring volume, humidity, gradient, vibration, odor, or infrared. By providing the sensor 921, for example, data indicating the environment in which the storage battery is placed ( It is also possible to detect a temperature or the like and store it in a memory in the circuit 912.

[0199] Furthermore, an example of the structure of the storage battery 913 will be described with reference to FIGS.

[0200] The storage battery 913 shown in FIG. 19(A) has a terminal 951 and a terminal 952 provided inside a housing 930. The winding 950 is impregnated with an electrolyte inside the housing 930. The terminal 952 is in contact with the housing 930, and the terminal 951 is in contact with the housing by using an insulating material or the like. 19A, the housing 930 is not in contact with the housing 930. For convenience, the housing 930 is shown in a separated state. However, in reality, the winding body 950 is covered by the housing 930, and the terminals 951 and 952 are The housing 930 is made of a metal material or a resin material. It is possible.

[0201] As shown in FIG. 19(B), the housing 930 shown in FIG. 19(A) is made of a plurality of materials. For example, the storage battery 913 shown in FIG. 19B may be formed by a housing 930a and a housing 93 The area surrounded by the housing 930a and the housing 930b is where the wound body 95 0 is provided.

[0202] The housing 930a can be made of an insulating material such as organic resin. By using a material such as organic resin on the surface where the electric field is formed, the electric field shielding by the storage battery 913 can be prevented. If the shielding of the electric field by the housing 930a is small, the inside of the housing 930a can be suppressed. Antennas such as antenna 914 and antenna 915 may be provided in the housing 930b. For example, a metal material can be used.

[0203] Furthermore, the structure of the wound body 950 is shown in Fig. 20. The wound body 950 is made up of a negative electrode 931 and a positive electrode 932. The winding body 950 has a pole 932 and a separator 933. The negative electrode 931 and the positive electrode 932 are stacked one on top of the other, and the laminated sheet is wound to form a wound body. The negative electrode 931, the positive electrode 932, and the separator 933 may be further laminated. You can stack several of them.

[0204] The negative electrode 931 is connected to the terminal 911 shown in FIG. 16 via one of the terminals 951 and 952. The positive electrode 932 is connected to the terminal 91 shown in FIG. 16 via the other of the terminals 951 and 952. Connected to 1.

[0205] <Example of electronic device: Installed in a vehicle> Next, we will show an example of installing a storage battery in a vehicle. Hybrid electric vehicles (HEV), electric vehicles (EV), plug-in hybrid vehicles (PHEV), etc. This will make next-generation clean energy vehicles a reality.

[0206] 21A and 21B show examples of vehicles using one embodiment of the present invention. 100 is an electric vehicle that uses an electric motor as a power source for running. A hybrid vehicle that can select between an electric motor and an engine as a power source for driving. By using one embodiment of the present invention, the battery can be repeatedly charged and discharged. The automobile 8100 also has a storage battery. It not only drives the electric motor, but also the headlight 8101 and room light (not shown). Any light emitting device can be powered.

[0207] In addition, the storage battery is used to power the display devices such as the speedometer and tachometer of the automobile 8100. The storage battery can also supply power to the navigation system of the automobile 8100. The present invention can provide power to semiconductor devices such as communication systems.

[0208] The automobile 8200 shown in FIG. 21(B) has a plug-in type storage battery. It can be charged by receiving power from an external charging facility using a wireless power supply system. FIG. 21(B) shows the charging of a battery mounted on a vehicle 8200 from a ground-mounted charging device 8021. The battery is being charged via cable 8022. The charging device 8021 may be installed in a commercial facility. This may be a charging station provided or a home power source. For example, Using in-vehicle technology, the battery installed in the vehicle 8200 can be charged using an external power supply. Charging is done by converting AC power to DC power via a converter such as an AC-DC converter. This can be done by converting it into electricity.

[0209] 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 battery may be installed to charge the battery when the vehicle is stopped or running. The power can be supplied using an electromagnetic induction method or a magnetic field resonance method.

[0210] According to one aspect of the present invention, the cycle characteristics of the storage battery are improved, and the reliability is improved. Furthermore, according to one aspect of the present invention, the characteristics of the storage battery can be improved, and therefore, If the storage battery itself can be made smaller and lighter, the vehicle's This contributes to weight reduction, which can improve the driving range. The pond can also be used as a power source for non-vehicles. In this case, the peak demand for electricity is It is possible to avoid using a commercial power source.

[0211] (Fourth embodiment) The storage batteries described in the first to third embodiments can be used in combination with the battery cells. Battery Management Unit (BMU) ), and transistors suitable for the circuits that constitute the battery control unit are shown in FIGS. This will be explained with reference to Figure 28. In this embodiment, a battery having battery cells connected in series is used. The battery control unit of the storage battery will now be described.

[0212] When multiple battery cells connected in series are repeatedly charged and discharged, the characteristics between the battery cells change. The capacity (output voltage) varies depending on the variation in the The overall discharge capacity depends on the battery cell with the smallest capacity. Also, if charging is performed based on a battery cell with a small capacity, the charging In addition, if charging is performed based on the battery cell with the larger capacity, it may result in overcharging. There is a risk that this may happen.

[0213] Therefore, the battery control unit of a storage battery having battery cells connected in series is required to detect insufficient charge or This function is to equalize the capacity variations between battery cells, which can cause overcharging. The circuit configuration to equalize the capacitance variation can be a resistor type, a capacitor type, or an inductor type. However, here we use a transistor with a small off-current to even out the capacitance variation. An example of a circuit configuration that can be achieved will be described below.

[0214] As a transistor with low off-state current, a transistor having an oxide semiconductor in a channel formation region is OS transistors with low off-state current are preferred. By using this in the circuit configuration of the battery control unit, the amount of charge leaking from the battery is reduced, and the time This can suppress the decrease in capacity over time.

[0215] The oxide semiconductor used in the channel formation region is In-M-Zn oxide (M is Ga, Sn, Y, Zr, La, Ce, or Nd) is used to form an oxide semiconductor film. In the target, if the atomic ratio of metal elements is In:M:Zn=x1:y1:z1, 、 x1 / y1 is 1 / 3 or more and 6 or less, and further 1 or more and 6 or less, and z1 / y1 is 1 It is preferable that z1 / y1 is 1 or more and 6 or less, and more preferably 1 or more and 6 or less. When the upper limit is 6 or less, a CAAC-OS film is easily formed as the oxide semiconductor film.

[0216] Here, the CAAC-OS film will be described.

[0217] The CAAC-OS film is one of oxide semiconductor films having a plurality of crystal parts aligned along the c-axis.

[0218] Transmission Electron Microscope (TEM) A bright-field image and a combined analysis image of the diffraction pattern of the CAAC-OS film were obtained by using a microscope. By observing the TEM image, multiple crystalline regions can be identified. On the other hand, high-resolution TEM images also reveal clear boundaries between crystalline parts, i.e., grain boundaries. Therefore, the CAAC-OS film is It can be said that the decrease in electron mobility caused by grain boundaries is unlikely to occur.

[0219] When a high-resolution TEM image of the cross section of the CAAC-OS film was observed from a direction approximately parallel to the sample surface, It can be seen that the metal atoms are arranged in layers in the crystalline part. Each layer of metal atoms is The CAAC-OS film is formed on a surface (also called a surface to be formed) or on a surface that reflects the unevenness of the surface. The CAAC-OS film has a shape and is aligned parallel to the surface on which the film is formed or the upper surface.

[0220] On the other hand, a high-resolution TEM image of the plane of the CAAC-OS film was observed from a direction approximately perpendicular to the sample surface. It was confirmed that the metal atoms in the crystals were arranged in a triangular or hexagonal shape. However, there is no regularity in the arrangement of metal atoms between different crystal parts.

[0221] X-ray diffraction (XRD) was performed on the CAAC-OS film. For example, a CAAC-OS film with InGaZnO4 crystals was found by structural analysis using the device. In the out-of-plane analysis, a peak was observed at a diffraction angle (2θ) of approximately 31°. This peak is attributed to the (009) plane of the InGaZnO4 crystal. Therefore, the crystals of the CAAC-OS film have a c-axis orientation, and the c-axis is approximately aligned on the surface on which the film is formed or on the upper surface. You can see that it is oriented vertically.

[0222] In addition, the out-of-plane method of CAAC-OS film with InGaZnO4 crystals In the analysis by , in addition to the peak at 2θ around 31°, a peak also appeared at 2θ around 36°. The peak at 2θ around 36° is due to the presence of c-axis orientation in part of the CAAC-OS film. The CAAC-OS film contains crystals that do not have a 2θ of around 31°. It is preferable that the peak is exhibited at 2θ of around 36° and that the peak is not exhibited at 2θ of around 36°.

[0223] The CAAC-OS film is an oxide semiconductor film with a low concentration of impurities. These are elements other than the main components of the oxide semiconductor film, such as silicon and transition metal elements. The elements that bond to oxygen more strongly than the metal elements that constitute the oxide semiconductor film, such as fluorine, are oxidized. By removing oxygen from the oxide semiconductor film, the atomic arrangement of the oxide semiconductor film is disrupted, reducing its crystallinity. In addition, heavy metals such as iron and nickel, argon, and carbon dioxide have an atomic radius (or molecular radius) is large, and when it is contained inside the oxide semiconductor film, The impurities contained in the oxide semiconductor film are likely to disturb the atomic arrangement and cause a decrease in crystallinity. Objects can act as carrier traps or carrier sources.

[0224] The CAAC-OS film is an oxide semiconductor film with a low density of defect states. Oxygen vacancies in the semiconductor film can become carrier traps or trap hydrogen, It can be a source of carrier generation.

[0225] Low impurity concentration and low defect level density (low oxygen vacancies) are called high purity intrinsic or The term "substantially highly purified intrinsic" refers to a highly purified intrinsic or substantially highly purified intrinsic oxide semiconductor film. Since there are fewer carrier generation sources, the carrier density can be reduced. The transistor using the oxide semiconductor film has electrical characteristics ( It is also called normally-on.) It is rare for it to become a high-purity intrinsic or substantially high-purity The intrinsic oxide semiconductor film has few carrier traps. Transistors using this film have little fluctuation in electrical characteristics and are highly reliable. Note that it takes time for the charges trapped in the carrier traps in the oxide semiconductor film to be released. The impurity concentration is high and the charge is stable for a long time, so the charge may behave like a fixed charge. Therefore, a transistor using an oxide semiconductor film with a high density of defect states has unstable electrical characteristics. This may occur.

[0226] In addition, transistors using CAAC-OS films show improved electrical characteristics when irradiated with visible light or ultraviolet light. The fluctuation is small.

[0227] Note that an OS transistor is a transistor having silicon in a channel formation region (Si transistor). Since the band gap is larger than that of a semiconductor (transistor), dielectric breakdown does not occur when a high voltage is applied. When battery cells are connected in series, a voltage of several hundred volts is generated. The circuit configuration of the battery control unit of the storage battery applied to such a battery cell includes the above-mentioned OS transistor. It is suitable to configure it with a transistor.

[0228] An example of a block diagram of a storage battery is shown in Fig. 22. The storage battery BT00 shown in Fig. 22 has a terminal pair BT01, a terminal pair BT02, a switching control circuit BT03, and a switching circuit BT04. , a switching circuit BT05, a transformer control circuit BT06, and a transformer circuit BT07 are connected in series. and a battery unit BT08 including a plurality of battery cells BT09.

[0229] In addition, in the storage battery BT00 of FIG. 22, the terminal pair BT01 and the terminal pair BT02 are switched. A control circuit BT03, a switching circuit BT04, a switching circuit BT05, and a transformer control circuit The part consisting of the circuit BT06 and the transformer circuit BT07 is called the battery control unit. This can be done.

[0230] The switching control circuit BT03 controls the operations of the switching circuits BT04 and BT05. Specifically, the switching control circuit BT03 controls the measured voltage of each battery cell BT09. Based on the voltage, the battery cells to be discharged (discharge battery cell group) and the battery cells to be charged (charge battery group) are selected. Determine the pond cell group.

[0231] Furthermore, the switching control circuit BT03 controls the determined discharge battery cell group and charge battery cell group. The control signal S1 and the control signal S2 are output based on the group. This control signal S1 connects the terminal pair BT01 and the discharge battery cell group. The control signal S2 is a signal that controls the switching circuit BT04 so as to connect the This control signal S2 is output to the switching circuit BT05. This is a signal that controls the switching circuit BT05 to connect the group.

[0232] The switching control circuit BT03 includes the switching circuits BT04, BT05, and Considering the configuration of the transformer circuit BT07, the same polarity is The control signal S1 and the control signal S2 are generated so that the positive terminals are connected to each other.

[0233] The operation of the switching control circuit BT03 will now be described in detail.

[0234] First, the switching control circuit BT03 measures the voltage of each of the plurality of battery cells BT09. The switching control circuit BT03 then selects, for example, the battery cell BT09 having a voltage equal to or higher than a predetermined threshold. High voltage battery cells (high voltage cells), battery cells BT09 with voltages below a certain threshold are classified as low voltage It is determined to be a battery cell (low voltage cell).

[0235] There are various methods for determining whether a cell is a high-voltage cell or a low-voltage cell. For example, the switching control circuit BT03 selects the battery with the highest current among multiple battery cells BT09. The voltage of each battery cell BT0 is determined based on the voltage of the battery cell BT09 with the highest or lowest voltage. 9 may be a high-voltage cell or a low-voltage cell. In this case, the switching control circuit BT03 determines whether the voltage of each battery cell BT09 is equal to or greater than a predetermined ratio of the reference voltage. By doing so, it is possible to determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell. Then, the switching control circuit BT03 switches between the discharging battery cell group and the charging battery cell group based on the result of this judgment. Determine the pond cell group.

[0236] In addition, among the multiple battery cells BT09, high voltage cells and low voltage cells are mixed in various states. For example, the switching control circuit BT03 can select the voltage between high-voltage cells and low-voltage cells. The part with the most high-voltage cells connected in series is the discharge battery cell group. The switching control circuit BT03 charges the part with the most low-voltage cells connected in series. The switching control circuit BT03 detects whether the battery cells are close to being overcharged or overdischarged. Even if the battery cell group BT09 is preferentially selected as a discharge battery cell group or a charge battery cell group, good.

[0237] An example of the operation of the switching control circuit BT03 in this embodiment will now be described with reference to FIG. FIG. 23 is a diagram for explaining an example of the operation of the switching control circuit BT03. For convenience of explanation, FIG. 23 shows an example in which four battery cells BT09 are connected in series. Reveal.

[0238] First, in the example of FIG. 23(A), if the voltages of battery cells a to d are voltages Va to Vd, then , Va=Vb=Vc>Vd. In other words, three consecutive high voltages The high-voltage cells a to c and one low-voltage cell d are connected in series. The control circuit BT03 determines three consecutive high-voltage cells a to c as a discharge battery cell group. In addition, the switching control circuit BT03 determines the low voltage cell d as the charging battery cell group. .

[0239] Next, the example of FIG. 23(B) shows a case where the relationship is Vc>Va=Vb>>Vd. In other words, between two consecutive low voltage cells a and b, one high voltage cell c, and one over-discharge In this case, the switching control circuit BT03 is configured as follows: The high-voltage cell c is determined as the discharge battery cell group. Since the high-voltage cell d is close to over-discharge, it is the low-voltage cell a and b that are the two consecutive low-voltage cells. The pressure cell d is determined as the charging battery cell group with priority.

[0240] Finally, the example of FIG. 23(C) shows a case where the relationship Va>Vb=Vc=Vd holds. That is, one high-voltage cell a and three consecutive low-voltage cells b to d are connected in series. In this case, the switching control circuit BT03 determines the high voltage cell a as the discharge battery cell group. The switching control circuit BT03 also determines whether to charge three consecutive low-voltage cells b to d. Determined as a battery cell group.

[0241] The switching control circuit BT03 determines the results as shown in the examples of FIGS. 23(A) to 23(C). Based on this, information indicating the discharge battery cell group to which the switching circuit BT04 is connected is set. The control signal S1 and information indicating the charging battery cell group to which the switching circuit BT05 is connected are set. The control signal S2 thus determined is sent to the switching circuit BT04 and the switching circuit BT05. Each is output.

[0242] The above is a detailed explanation of the operation of the switching control circuit BT03.

[0243] The switching circuit BT04 is responsive to the control signal S1 output from the switching control circuit BT03. The connection destination of the terminal pair BT01 is set to the discharge battery cell determined by the switching control circuit BT03. Set it to the rule group.

[0244] The terminal pair BT01 is composed of a pair of terminals A1 and A2. In this case, either one of the terminals A1 and A2 is connected to the most upstream (high voltage) of the discharge battery cell group. The other end is connected to the positive terminal of the battery cell BT09 located at the top of the discharge battery cell group. By connecting it to the negative terminal of the battery cell BT09 located downstream (low potential side), The switching circuit BT04 is set to the connection destination of the pair BT01. The position of the discharged battery cell group can be recognized using the obtained information.

[0245] The switching circuit BT05 is responsive to the control signal S2 output from the switching control circuit BT03. The connection destination of the terminal pair BT02 is determined by the switching control circuit BT03. Set it to the rule group.

[0246] The terminal pair BT02 is composed of the pair of terminals B1 and B2. In this case, either one of the terminals B1 and B2 is connected to the most upstream (high voltage) of the charging battery cell group. The other end is connected to the positive terminal of the battery cell BT09 located at the top of the charging battery cell group. By connecting it to the negative terminal of the battery cell BT09 located downstream (low potential side), The connection destination of the BT02 is set. The switching circuit BT05 is set by the control signal S2. The position of the charging battery cell group can be recognized using the obtained information.

[0247] 24 and 25 are circuit diagrams showing examples of the configuration of the switching circuits BT04 and BT05. Shown in 5.

[0248] In FIG. 24, the switching circuit BT04 includes a plurality of transistors BT10 and buses BT11 and BT12. The bus BT11 is connected to the terminal A1. 2 is connected to the terminal A2. One of them is alternately connected to buses BT11 and BT12. The other of the sources or drains of the plurality of transistors BT10 is connected to two adjacent It is connected between battery cells BT09.

[0249] Among the multiple transistors BT10, the transistor BT10 located at the most upstream position The other of the source and drain is connected to the positive electrode of the battery cell BT09 located at the most upstream of the battery module BT08. The transistor BT10 located at the most downstream position is connected to the terminal. The other of the source and drain of the transistor BT10 is located at the most downstream of the battery section BT08. It is connected to the negative terminal of the battery cell BT09.

[0250] The switching circuit BT04 controls the control signal S1 to be applied to the gates of the plurality of transistors BT10. In response, one of the plurality of transistors BT10 connected to the bus BT11 and and one of the plurality of transistors BT10 connected to T12 are brought into a conductive state. By doing so, the discharge battery cell group and the terminal pair BT01 are connected. The positive terminal of the battery cell BT09, which is located most upstream in the group of cells, is connected to the terminal A1 or A2 of the terminal pair. 2. In addition, the battery cell located most downstream in the discharge battery cell group is connected to either The negative terminal of the BT09 terminal is the other of the terminals A1 or A2 of the terminal pair, i.e., the positive terminal The terminal that is not connected to the

[0251] It is preferable to use an OS transistor for the transistor BT10. Since the off-state current of the capacitor is small, it reduces the amount of charge leaking from battery cells that do not belong to the discharge battery cell group. This prevents the capacitance from decreasing over time. Therefore, the output voltage of the discharged battery cell group is large. Even if the transistor BT10 is not in a conductive state, the battery cell BT09 and the terminal pair It is possible to insulate the BT01.

[0252] In addition, in FIG. 24, the switching circuit BT05 includes a plurality of transistors BT13 and a current control The bus BT15 and the bus BT16 are connected to the switch BT14. 16 is disposed between the plurality of transistors BT13 and the current control switch BT14. The sources or drains of the plurality of transistors BT13 are alternately connected to each other. The buses BT15 and BT16 are connected to the plurality of transistors BT13. The other of the source and drain is connected between two adjacent battery cells BT09. are.

[0253] Among the multiple transistors BT13, the transistor BT13 located at the most upstream The other of the source and drain is connected to the positive electrode of the battery cell BT09 located at the most upstream of the battery module BT08. The transistor BT13 located at the most downstream position is connected to the terminal. The other of the source and drain of the transistor BT13 is located at the most downstream of the battery section BT08. It is connected to the negative terminal of the battery cell BT09.

[0254] The transistor BT13 is an OS transistor, similar to the transistor BT10. Since the OS transistor has a small off-state current, it is preferable that the OS transistor does not belong to the rechargeable battery cell group. This reduces the amount of charge leaking from the battery cell and prevents the capacity from decreasing over time. In addition, OS transistors are less likely to experience dielectric breakdown when high voltages are applied. Transistor BT that remains non-conductive even when the voltage for charging the battery cell group is large. The battery cell BT09 to which the terminal pair BT02 is connected can be insulated from the terminal pair BT02.

[0255] The current control switch BT14 has a switch pair BT17 and a switch pair BT18. One end of the switch pair BT17 is connected to the terminal B1. The end is branched by two switches, one of which is connected to bus BT15 and the other The switch pair BT16 is connected to the bus BT16. One end of the switch pair BT18 is connected to the terminal B2. The other end of the switch pair BT18 is branched into two switches, while The switch is connected to bus BT15, and the other switch is connected to bus BT16. .

[0256] The switches included in the switch pair BT17 and the switch pair BT18 are transistors BT10 Similarly to the transistor BT13, an OS transistor is preferably used.

[0257] The switching circuit BT05 switches the transistor BT13 and the current control By controlling the combination of on / off states of the switch BT14, the charging battery cell group and terminal pair BT02.

[0258] As an example, the switching circuit BT05 connects the charging battery cell group and the terminal pair BT0 as follows: Connect 2.

[0259] The switching circuit BT05 controls the control signal S2 to be applied to the gates of the plurality of transistors BT13. In response, the positive terminal of the battery cell BT09 located most upstream in the charging battery cell group is connected. The switching circuit BT05 turns on the transistor BT13 connected to the In response to the control signal S2 applied to the gate of the transistor BT13, Transistor BT13 connected to the negative terminal of the most downstream battery cell BT09 is put into a conductive state.

[0260] The polarity of the voltage applied to terminal pair BT02 is the same as that of the discharge battery cell group connected to terminal pair BT01. The method of charging the battery cell group may vary depending on the configuration of the transformer circuit BT07. To allow current to flow in the same direction, the terminals of the same polarity must be connected between the terminal pair BT02 and the charging battery cells. Therefore, the current control switch BT14 is controlled by the control signal S2 as follows: Depending on the polarity of the voltage applied to terminal pair BT02, switch pair BT17 and switch pair BT It is controlled to switch between each of the 18 connection destinations.

[0261] As an example, a voltage is applied to the terminal pair BT02 such that terminal B1 is positive and terminal B2 is negative. At this time, the most downstream battery cell BT09 of the battery module BT08 If the battery cell group is a charging battery cell group, the switch pair BT17 switches the battery cell group by the control signal S2. The positive terminal of the switch pair BT17 is connected to the positive terminal of the switch pair BT09. The switch connected to bus BT16 is turned on, and the bus BT1 of switch pair BT17 is turned on. On the other hand, the switch pair BT18 is in the OFF state when the control signal S2 This controls the connection to the negative terminal of the battery cell BT09. The switch connected to the bus BT15 of the switch pair BT18 is turned on, and The switch connected to the bus BT16 of T18 is turned off. Between the BT02 and the charging battery cell group, terminals with the same polarity are connected. The direction of the current flowing from the BT02 slave pair is controlled so that it charges the battery cell group. will be done.

[0262] Also, the current control switch BT14 is connected to the switching circuit BT05, not the switching circuit BT It may be included in 04.

[0263] FIG. 25 shows a configuration example of the switching circuit BT04 and the switching circuit BT05, which is different from that shown in FIG. FIG.

[0264] In FIG. 25, the switching circuit BT04 includes a plurality of transistor pairs BT21 and a bus BT24. and a bus BT25. The bus BT24 is connected to the terminal A1. BT25 is connected to the terminal A2. Each of them is branched by the transistor BT22 and the transistor BT23. One of the source and drain of BT22 is connected to the bus BT24. One of the source and drain of the resistor BT23 is connected to the bus BT25. The other ends of the plurality of transistor pairs are connected between two adjacent battery cells BT09. Among the multiple transistor pairs BT21, the transistor located at the most upstream The other end of the pair BT21 is connected to the positive terminal of the battery cell BT09 located at the most upstream of the battery section BT08. In addition, among the plurality of transistor pairs BT21, the transistor located at the most downstream The other end of the resistor pair BT21 is connected to the negative electrode of the battery cell BT09 located at the most downstream of the battery unit BT08. is connected to the terminal.

[0265] The switching circuit BT04 switches between the transistor BT22 and the transistor BT30 in response to the control signal S1. By switching the conductive / non-conductive state of BT23, the connection of the transistor pair BT21 is The connection destination is switched to either terminal A1 or terminal A2. If T22 is conductive, transistor BT23 is non-conductive and is connected to terminal On the other hand, if the transistor BT23 is in a conducting state, the transistor BT22 The transistors BT22 and BT23 are in a non-conducting state and are connected to the terminal A2. Which of the switches BT23 is turned on is determined by a control signal S1.

[0266] Two transistor pairs BT21 are used to connect the terminal pair BT01 to the discharge battery cell group. In detail, the connection destination of the two transistor pairs BT21 is determined based on the control signal S1. By determining the terminal pair BT01 and the terminal pair BT02, the discharge battery cell group is connected to the terminal pair BT01. One of the two transistor pairs BT21 is connected to terminal A1, and the other is connected to terminal A2 by the control signal S1.

[0267] The switching circuit BT05 includes a plurality of transistor pairs BT31, a bus BT34, and a bus BT The bus BT34 is connected to the terminal B1. The bus BT35 has One end of each of the plurality of transistor pairs BT31 is connected to the terminal B2. The output is branched by the transistor BT32 and the transistor BT33. One end of the branched signal is connected to a bus BT34. One end of the branch is connected to a bus BT35. The other end of each is connected between two adjacent battery cells BT09. The other end of the transistor pair BT31 located at the most upstream of the transistor pairs BT31 is It is connected to the positive terminal of the battery cell BT09 located at the most upstream position of the battery unit BT08. Among the plurality of transistor pairs BT31, other than the transistor pair BT31 located at the most downstream The end is connected to the negative terminal of the battery cell BT09 located at the most downstream of the battery unit BT08. .

[0268] The switching circuit BT05 switches between the transistor BT32 and the transistor BT33 in response to the control signal S2. By switching the conductive / non-conductive state of BT33, the connection of the transistor pair BT31 is The connection destination is switched to either terminal B1 or terminal B2. If T32 is conductive, transistor BT33 is non-conductive and is connected to terminal Conversely, if the transistor BT33 is in a conducting state, the transistor BT32 The transistors BT32 and BT33 are in a non-conducting state and are connected to the terminal B2. Which of the switches BT33 is turned on is determined by a control signal S2.

[0269] Two transistor pairs BT31 are used to connect the terminal pair BT02 to the charging battery cells. In detail, the connection destination of the two transistor pairs BT31 is determined based on the control signal S2. By determining the terminal pair BT02, the charging battery cell group is connected to the terminal pair BT02. One of the two transistor pairs BT31 is connected to terminal B1, and the other is connected to terminal B2 by the control signal S2.

[0270] The two transistor pairs BT31 are connected to the terminal pair BT02. Specifically, terminal B1 is positive and terminal B2 is negative. When such a voltage is applied to the terminal pair BT02, the upstream transistor pair BT31 , the transistor BT32 is in a conducting state and the transistor BT33 is in a non-conducting state. On the other hand, the downstream transistor pair BT31 is controlled by the control signal S2. The transistor BT33 is controlled to be in a conductive state and the transistor BT32 is controlled to be in a non-conductive state. It is controlled by the signal S2. Also, the voltage that makes the terminal B1 negative and the terminal B2 positive is When a voltage is applied to the terminal pair BT02, the upstream transistor pair BT31 The control is performed so that the transistor BT33 is in a conducting state and the transistor BT32 is in a non-conducting state. On the other hand, the downstream transistor pair BT31 is controlled by the transistor The control signal S2 is supplied to the transistor BT32 so that the transistor BT32 is in a conducting state and the transistor BT33 is in a non-conducting state. In this way, the same voltage is applied between the terminal pair BT02 and the charging battery cell group. The terminals with the same polarity are connected together. The direction of the current flowing from the terminal pair BT02 is The battery cells are controlled to charge.

[0271] The transformer control circuit BT06 controls the operation of the transformer circuit BT07. , the number of battery cells BT09 included in the discharge battery cell group and the number of battery cells BT09 included in the charge battery cell group Based on the number of cells BT09, a transformer signal S3 is generated to control the operation of the transformer circuit BT07. and outputs it to the transformer circuit BT07.

[0272] The number of battery cells BT09 included in the discharge battery cell group is equal to the number of battery cells BT09 included in the charge battery cell group. If the number of battery cells is greater than the number of BT09, an excessively large charging voltage will be applied to the charging battery cell group. Therefore, the transformer control circuit BT06 is The transformer circuit BT07 is used to lower the discharge voltage (Vdis) to a level that allows the cells to be charged. It outputs a control transformer signal S3.

[0273] In addition, the number of battery cells BT09 included in the discharge battery cell group is If the number of battery cells is less than or equal to the number of BT09, the charge required to charge the battery cell group is Therefore, the voltage transformer control circuit BT06 detects excess voltage in the charging battery cell group. The transformer circuit BT is designed to boost the discharge voltage (Vdis) within a range where an excessive charge voltage is not applied. 07.

[0274] The voltage value that constitutes the excessive charging voltage is the voltage of the battery cell BT09 used in the battery module BT08. This can be determined in consideration of product specifications, etc. Also, the voltage step-up and step-down can be performed by the transformer circuit BT07. The voltage thus obtained is applied to the terminal pair BT02 as the charging voltage (Vcha).

[0275] Here, an example of the operation of the transformer control circuit BT06 in this embodiment is shown in FIGS. 26(A) to 26(C). 26(A) to 26(C) show the discharges explained in FIGS. 23(A) to 23(C). An example of the operation of the voltage transformer control circuit BT06 corresponding to the battery cell group and the charge battery cell group will be explained. 26(A) to 26(C) are conceptual diagrams illustrating the battery control unit BT41. As described above, the battery control unit BT41 has the terminal pair BT01 and the terminal pair B T02, a switching control circuit BT03, a switching circuit BT04, and a switching circuit BT0 5, a voltage transformation control circuit BT06, and a voltage transformation circuit BT07.

[0276] In the example shown in FIG. 26(A), three consecutive high voltages are applied as explained in FIG. 23(A). Cells a to c and one low-voltage cell d are connected in series. In this case, as shown in FIG. As explained above with reference to the example of the switching control circuit BT03, the switching control circuit BT03 controls the high voltage cells a to c to the discharge voltage. The low-voltage cell d is determined as the battery cell group, and the low-voltage cell d is determined as the charging battery cell group. The control circuit BT06 is based on the number of battery cells BT09 included in the discharge battery cell group. , based on the ratio of the number of battery cells BT09 included in the charging battery cell group, the discharge voltage (Vdi Calculate the conversion ratio N from the current (V) to the charging voltage (Vcha).

[0277] The number of battery cells BT09 included in the discharge battery cell group is equal to the number of battery cells BT09 included in the charge battery cell group. If the number of battery cells is greater than the number of BT09, the discharge voltage is directly applied to the terminal pair BT02 without being transformed. When this voltage is applied, a voltage is applied to battery cell BT09 in the charging battery cell group via terminal pair BT02. There is a possibility that excessive voltage will be applied. Therefore, in the case shown in FIG. Therefore, the charging voltage (Vcha) applied to the terminal pair BT02 must be lower than the discharging voltage. Furthermore, in order to charge the battery cell group, the charging voltage must be It must be greater than the total voltage of the included battery cells BT09. Therefore, the voltage transformer control circuit B T06 is the charging voltage when the number of battery cells BT09 included in the discharge battery cell group is used as the reference. The conversion ratio N is set to be larger than the ratio of the number of battery cells BT09 included in the battery cell group.

[0278] The transformer control circuit BT06 determines the number of battery cells BT09 included in the discharge battery cell group as a standard. When the conversion ratio N is 1, the ratio of the number of battery cells BT09 included in the charging battery cell group is At this time, the charging voltage is preferably set to be about 10% or more higher than the voltage of the charging battery cell group. However, the charging voltage is actually equal to the voltage of the charging battery cell group. The control circuit BT06 controls the voltage of the charging battery cell group to be equal to the charging voltage according to the conversion ratio N. This current flows to charge the battery cell group. The set value will be used.

[0279] In the example shown in FIG. 26(A), the number of battery cells BT09 included in the discharge battery cell group is 3. Since the number of battery cells included in the charging battery cell group is one, the voltage transformer control circuit The BT06 calculates a conversion ratio N that is slightly larger than 1 / 3. BT06 converts the discharge voltage into a charge voltage by converting the discharge voltage into a charge voltage according to the conversion ratio N. The transformer circuit BT07 then outputs the voltage signal S3 to the transformer circuit BT07. The charging voltage applied to the terminal pair BT02 is then applied to the terminal pair BT02. The battery cell BT09 included in the charging battery cell group is charged by the charging voltage.

[0280] In the examples shown in FIG. 26(B) and FIG. 26(C), as in FIG. 26(A), the conversion ratio N In the examples shown in FIG. 26(B) and FIG. 26(C), the The number of battery cells BT09 included in the charging battery cell group is less than or equal to the number of battery cells BT09 included in the charging battery cell group. Therefore, the conversion ratio N is 1 or more. The transformer outputs a transformer signal S3 that boosts the applied voltage and converts it into a charging voltage.

[0281] The transformer circuit BT07 adjusts the discharge voltage applied to the terminal pair BT01 based on the transformer signal S3. The transformer circuit BT07 converts the converted charging voltage into a charging voltage. 2. Here, the transformer circuit BT07 connects the terminal pair BT01 and the terminal pair BT02. This allows the transformer circuit BT07 to be electrically isolated from the lowest discharged battery cell group. The absolute voltage of the negative terminal of the battery cell BT09 located downstream and the most downstream of the charging battery cells This prevents a short circuit due to a difference in absolute voltage between the negative terminal of the battery cell BT09 located at the Then, as described above, the transformer circuit BT07 converts the sum of the discharged battery cell groups into the sum of the discharged battery cells based on the transformer signal S3. The discharge voltage, which is the measured voltage, is converted into the charge voltage.

[0282] The transformer circuit BT07 is, for example, an isolated DC (Direct Current)-DC In this case, the transformer control circuit BT06 is an isolated DC- The signal that controls the on / off ratio (duty ratio) of the DC converter is the transformer signal S3. By outputting this voltage, the charging voltage converted by the transformer circuit BT07 is controlled.

[0283] In addition, there are various types of isolated DC-DC converters, including flyback, forward, and RCC ( Ring Choke Converter type, push-pull type, half-block type There are various types of inverters, such as full-bridge and ridge types, depending on the desired output voltage. The appropriate method is selected based on the results.

[0284] The configuration of the transformer circuit BT07 using an isolated DC-DC converter is shown in Figure 27. The C-DC converter BT51 has a switch unit BT52 and a transformer unit BT53. The switch BT52 is a switch that switches the operation of the isolated DC-DC converter on and off. For example, MOSFET (Metal-Oxide-Semiconductor tor Field-Effect Transistor) and bipolar transistor The switch unit BT52 is realized by using a transformer or the like. Based on the transformer signal S3 that controls the on / off ratio, the isolated DC-DC converter The switch BT51 is periodically switched between the on and off states. Various configurations are possible depending on the type of isolated DC-DC converter used. BT53 converts the discharge voltage applied from the terminal pair BT01 into a charge voltage. The transformer section BT53 operates in conjunction with the on / off state of the switch section BT52. The discharge voltage is converted into a charge voltage according to the on / off ratio. This charge voltage is In the switching period of 2, the longer the ON time, the larger the capacitance becomes. The voltage is increased as the ON time of the switch unit BT52 is shorter in the switching period. When using an isolated DC-DC converter, the transformer part BT53 Internally, terminal pair BT01 and terminal pair BT02 can be isolated from each other.

[0285] The processing flow of storage battery BT00 in this embodiment will be described with reference to FIG. 28. 10 is a flowchart showing the flow of processing by storage battery BT00.

[0286] First, the storage battery BT00 acquires the voltage measured for each of the plurality of battery cells BT09 (step The storage battery BT00 operates to equalize the voltages of multiple battery cells BT09. It is determined whether or not the start condition of the operation is satisfied (step S002). The difference between the maximum and minimum voltages measured for each of the plurality of battery cells BT09 is a predetermined threshold value. If this start condition is not met (step S002 :NO), the voltages of the battery cells BT09 are balanced, so the battery B T00 does not execute the subsequent processing. On the other hand, if the start condition is met (step S002 If the answer is YES, the storage battery BT00 executes a process to make the voltages of the battery cells BT09 uniform. In the process, the storage battery BT00 calculates the voltage of each battery cell B based on the measured voltage of each cell. It is determined whether T09 is a high-voltage cell or a low-voltage cell (step S003). T00 determines the discharge battery cell group and the charge battery cell group based on the determination result (step Furthermore, the storage battery BT00 connects the determined discharge battery cell group to the terminal pair BT01. The control signal S1 sets the connection destination of the battery cell group, and the connection destination of the determined battery cell group is set to the terminal pair BT02. The storage battery BT00 generates a control signal S2 that sets the storage battery BT00 as the connection destination (step S005). The control signals S1 and S2 are transmitted to the switching circuits BT04 and BT0 5. Then, the switching circuit BT04 switches the terminal pair BT01 and the discharge voltage The terminal pair BT02 and the discharge battery cell group are connected by the switching circuit BT05. The storage battery BT00 is connected to the discharge battery cell group (step S006). The number of battery cells BT09 included in the charging battery cell group is Then, the storage battery BT00 generates a transformed signal S3 based on the calculated voltage (step S007). Based on the transformer signal S3, the discharge voltage applied to the terminal pair BT01 is converted into a charge voltage, and The voltage is applied to the battery pair BT02 (step S008). The battery cells are then moved to the battery cell group.

[0287] In addition, in the flowchart of FIG. 28, multiple steps are listed in order, but each step The order in which the steps are executed is not limited to the order in which they are listed.

[0288] As described above, according to this embodiment, when transferring charges from the discharge battery cell group to the charge battery cell group, Like the capacitor method, the charge from the discharged battery cells is first stored and then transferred to the charged battery cells. This eliminates the need for a configuration that emits electrons into groups. This increases the charge transfer efficiency per unit time. In addition, the switching circuits BT04 and BT05 can improve the Therefore, among the discharge battery cell group and the charge battery cell group, the battery cells connected to the transformer circuit are individually Can be switched.

[0289] Furthermore, the number of battery cells BT09 included in the discharge battery cell group is determined by the transformer circuit BT07. The number of battery cells BT09 included in the charging battery cell group is determined based on the number of terminals BT01 and BT02. The applied discharge voltage is converted into a charge voltage and applied to the terminal pair BT02. Regardless of the selection of the battery cell BT09 on the supply and charging sides, the charge transfer can be performed without any problems. It can be realized.

[0290] Furthermore, by using OS transistors for the transistors BT10 and BT13, As a result, leakage occurs from the battery cell BT09 that does not belong to the charging battery cell group or the discharging battery cell group. This reduces the charge amount of the battery cell BT09 that does not contribute to charging and discharging. In addition, OS transistors have the advantage over Si transistors in that they can suppress the decrease in capacitance. This causes the temperature of the battery cell BT09 to rise, However, normal operation, such as switching between conductive and non-conductive states according to the control signals S1 and S2, is also possible. It can be done.

[0291] Note that this embodiment mode can be implemented in appropriate combination with other embodiment modes. [Explanation of symbols]

[0292] 100 Lithium-ion battery 101 Positive electrode 101a Positive electrode current collector 101b Positive electrode active material layer 102 Negative electrode 102a Negative electrode current collector 102b Negative electrode active material layer 103 Graphene oxide film 103a First Area 103b Second Area 104 Positive lead 105 Negative lead 106 Electrolyte 107 Exterior body 108 Joint 109 Separator 300 storage battery 301 Positive electrode can 302 Anode can 303 Gasket 304 Positive electrode 305 Positive electrode current collector 306 Positive electrode active material layer 307 Negative electrode 308 Negative electrode current collector 309 Negative electrode active material layer 310 Separator 400 storage battery 402 Positive electrode 404 Negative electrode 406 Electrolyte 408 Separator 500 battery 501 Positive electrode current collector 502 Positive electrode active material layer 503 Positive electrode 504 Negative electrode current collector 505 Negative electrode active material layer 506 negative electrode 507 Separator 508 Electrolyte 509 Exterior body 510 Positive tab electrode 511 Negative tab electrode 531 Graphene oxide film 600 storage battery 601 Positive electrode cap 602 Battery can 603 Positive terminal 604 Positive electrode 605 Separator 606 negative electrode 607 Negative terminal 608 Insulating plate 609 Insulating board 610 Gasket 611 PTC element 612 Safety valve mechanism 900 Circuit Board 910 Label 911 terminal 912 circuits 913 Storage battery 914 Antenna 915 Antenna 916 layers 917 layers 918 Antenna 919 terminal 920 Display device 921 Sensor 922 terminal 930 chassis 930a housing 930b housing 931 negative electrode 932 Positive electrode 933 Separator 951 terminal 952 terminals 1700 curved surface 1701 Plane 1702 Curve 1703 Radius of curvature 1704 Center of curvature 1800 Center of curvature 1801 Film 1802 radius of curvature 1803 Film 1804 radius of curvature 1805 Battery materials 7100 Portable display devices 7101 Housing 7102 Display section 7103 Operation button 7104 Storage battery 7400 mobile phone 7401 Housing 7402 Display section 7403 Operation button 7404 External connection port 7405 Speaker 7406 Microphone 7407 Storage battery 8021 Charging device 8022 cable 8100 Automobiles 8200 Automobiles 8101 Headlight S1 control signal S2 control signal S3 transformer signal BT00 storage battery BT01 terminal pair BT02 terminal pair BT03 Switching control circuit BT04 switching circuit BT05 switching circuit BT06 Transformer control circuit BT07 transformer circuit BT08 battery part BT09 Battery Cell BT10 transistor BT11 Bus BT12 Bus BT13 transistor BT14 Current Control Switch BT15 Bus BT16 Bus BT17 Switch vs. BT18 Switch vs. BT21 Transistor Pair BT22 transistor BT23 transistor BT24 Bus BT25 Bus BT31 Transistor Pair BT32 transistor BT33 transistor BT34 Bus BT35 Bus BT41 Battery Control Unit BT51 Isolated DC-DC Converter BT52 switch part BT53 transformer S001 Step S002 Step S003 Step S004 Step S005 Step S006 Step S007 Step S008 Step

Claims

[Claim 1] The battery has a positive electrode, a negative electrode, and an outer casing, the positive electrode has a positive electrode current collector and a positive electrode active material layer made of a material different from that of the positive electrode current collector, the negative electrode has a negative electrode current collector and a negative electrode active material layer made of a material different from that of the negative electrode current collector, At least one of the positive electrode and the negative electrode is at least partially enclosed in a first film; the first film covers the periphery of the positive electrode current collector and the positive electrode active material layer, or the periphery of the negative electrode current collector and the negative electrode active material layer, the first film includes a graphene compound; the graphene compound has a seven-membered ring or more; the seven- or higher-membered ring has a region through which lithium ions can pass, the graphene compound has silylated graphene oxide, The positive electrode and the negative electrode are housed in the exterior housing of the lithium ion storage battery.

Images