Lithium-ion rechargeable battery

Abstract

To provide a secondary battery suitable for a portable information terminal or a wearable device, and alternatively to provide an electronic device of a novel structure having various external shapes, and a secondary battery having a shape suitable for the shape to solve a problem in which the secondary battery or the electronic device in which the secondary battery is installed is bent beyond its limit by an unintended large external force, resulting in an excessively small radius of curvature.SOLUTION: Inside a secondary battery, a structure is formed in which a separator is sandwiched between positive and negative electrodes. Between this structure and the exterior body, a thermoplastic material that becomes soft at temperatures close to the surface temperature of human skin (30°C to 37°C) is provided.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] One aspect of the present invention relates to a secondary battery. Or, the present invention relates to an object, a method, or a manufacturing method related thereto. Or, the present invention relates to a process, a machine, a manufacture, or a composition ( composition of matter). Or, one aspect of the present invention relates to a semiconductor device, a display device, a light-emitting device, an imaging device, a power storage device, a driving method thereof, or a manufacturing method thereof related thereto. In particular, it relates to electronic devices.

[0002] In this specification, an electronic device generally refers to a device having a secondary battery, and an electro-optical device having a secondary battery, an information terminal device having a secondary battery, a vehicle having a secondary battery, etc. are all electronic devices. [[ID=2I]]

Background Art

[0003] In recent years, portable information terminals typified by smartphones have been actively developed. There is a great demand for lightweight and compact portable information terminals, which are a type of electronic device. As an example of a wearable device that can obtain information visually regardless of location and without restricting the freedom of both hands, Patent Document 1 is disclosed. Patent Document 1 discloses a goggle-type display device capable of communication and including a CPU. The device of Patent Document 1 is also included in a type of electronic device.

[0004] <00001I9>

[0005] Wearable devices and portable information terminals often carry a secondary battery that can be repeatedly charged or discharged. Since wearable devices and portable information terminals are lightweight and compact, the capacity of the battery mounted thereon is limited. Therefore, the operation of wearable devices and portable information terminals ​​​​​​There is a problem with the limited production time. Two components to be installed in wearable devices and personal digital assistants. The next battery needs to be lightweight, compact, and capable of long operating times. Yes, they are.

[0006] Examples of rechargeable batteries include nickel-metal hydride batteries and lithium-ion rechargeable batteries. However, lithium-ion rechargeable batteries are undergoing active development because they offer high capacity and miniaturization. It is being said.

[0007] In lithium-ion secondary batteries, the electrodes that function as the positive or negative electrode are lithium Metals, carbon-based materials, alloy materials, etc. are used. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2005-157317 [Overview of the Initiative] [Problems that the invention aims to solve]

[0009] One of the objectives is to provide a rechargeable battery suitable for mobile information terminals or wearable devices. To do so. Alternatively, one of the objectives is to provide a novel energy storage device.

[0010] Alternatively, we will provide electronic devices with novel structures. Specifically, we will provide devices with various external shapes. To provide an electronic device with a novel structure that can do this. Or, a novel device with various external shapes. One of the challenges is to provide electronic devices with a suitable structure and secondary batteries with a shape appropriate to that structure. .

[0011] A large, unintended external force can damage a secondary battery, or an electronic device containing a secondary battery. The task is to resolve the problem of the equipment being bent beyond its limits, resulting in an excessively small radius of curvature. This will be the first topic.

[0012] Furthermore, the description of these problems does not preclude the existence of other problems. The approach does not necessarily have to solve all of these problems. This will become clear from the description in the specification, drawings, claims, etc., and the specification, drawings It is possible to extract other issues from the descriptions in the surfaces, claims, etc.

[0013] Electronic devices such as personal digital assistants and wearable devices require miniaturization and complex external shapes. There are requests such as: Furthermore, these electronic devices require rechargeable batteries. When miniaturizing or creating a complex external shape, electronic equipment is required to house the secondary battery. This results in a situation where the volume of the internal space becomes smaller and the shape becomes more complex.

[0014] The rechargeable batteries commonly used in personal digital assistants are rectangular batteries protected by a metal casing or a hard resin. It has a body shape.

[0015] Because the rectangular secondary battery itself is not flexible, it is not suitable for electronic devices with complex external shapes. When the internal space has a curved surface, a rectangular secondary battery can efficiently utilize that internal space. There are limits to what can be done.

[0016] Therefore, a rechargeable battery that is flexible and can change shape is used in electronic devices. Therefore, efficiently arranging secondary batteries in the internal space of electronic devices with complex external shapes is possible. can.

[0017] There are several ways to interpret what it means to give electronic devices a complex external shape. One is that electronic The device's exterior is given a complex shape, such as a curved shape, and is fixed in place. In some cases, the secondary battery is bent once and then fixed in that bent position. Furthermore, it is complicated. Electronic devices with a fixed external shape that do not deform when external force is applied, and those that change shape when force is applied. They can be divided into those that... Also, there are electronic devices with a simple external shape that are subjected to external force... It is something that is deformed by applying force. When an electronic device is deformed by applying force, the force It is desirable that the secondary battery can also change its external shape to a complex form each time it is used.

[0018] Wearable devices include wearable cameras, wearable microphones, and wearable microphones. Wearable input devices such as blue sensors, wearable displays, wearable Wearable output devices such as speakers, and wearable input devices that combine these functions. Includes output terminals. Furthermore, wearable devices are defined as devices that control each device or perform data calculations or This includes processing equipment, typically including wearable computers with CPUs. A wearable device is a device that stores, transmits, and receives data. This also includes mobile devices and memory devices.

[0019] The exterior is constructed by laminating metal foil (aluminum, stainless steel, etc.) and resin (heat-sealable resin). Using a film containing a laminate film, a secondary battery using a metal can is more efficient than a rechargeable battery using a metal can. It is also lightweight, and thin rechargeable batteries can be manufactured using this technology.

[0020] In secondary batteries using laminate film, the positive electrode, separator, and negative electrode are stacked alternately. It has a structure. This laminated structure is a commonly known sheet-like positive electrode, separator, negative electrode. Compared to secondary batteries with a wound electrode structure, it has the advantage of dissipating heat more easily.

[0021] Furthermore, the laminate film is flexible, and the positive and negative electrodes are made of thin metal or similar materials. Since it is a current collector and the separator is made of thin resin or similar material, this secondary battery is externally... Furthermore, it can deform into complex external shapes when force is applied.

[0022] One example of transforming a secondary battery into a complex external shape is to create a shape with curved surfaces. This allows for the efficient placement of secondary batteries within the internal space of electronic devices with complex external shapes. It is possible to make the electronic device complex while a secondary battery is placed inside the electronic device. It can be transformed into various external shapes.

[0023] When a large external force is applied to deform the laminate film into a complex external shape, The positive electrode, separator, and negative electrode may bend beyond their limits.

[0024] If bent beyond its limit, the laminate film will fold, and the secondary battery will not be able to return to its original shape. Furthermore, if the positive or negative electrode breaks or is severed, the exposed sharp cut surface will pierce the separator. This can cause problems such as the secondary battery short-circuiting and becoming unusable. Furthermore, If the radius of curvature becomes too small, the stress on the components of the secondary battery will also increase, and the current collector will... Problems such as the peeling of the active material may occur. [Means for solving the problem]

[0025] As electronic devices with complex external shapes, such as bendable and stretchable watches and bracelets, the ring Consider a product that is ring-shaped or partially missing.

[0026] Wristwatches and bracelets are worn around the body. Therefore, rechargeable batteries must be placed inside the electronic device. In such cases, a rechargeable battery that can be bent to wrap around a person's arm is preferable.

[0027] Furthermore, removing a watch or bracelet from the body requires loosening the bends in the electronic devices. When a secondary battery is placed inside an electronic device, two batteries that can be straightened out of a bent position are used. The next battery is preferable.

[0028] When wearing a wristwatch or bracelet around your body, your wrist or arm is inside the watch or bracelet. Therefore, if the radius of curvature becomes too small beyond the limits explained above, Such problems do not occur. However, when you are not wearing a watch or bracelet, unintended external noise may occur. A large force is applied from the part to the electronic device and the secondary battery located in the internal space of the electronic device. There is a risk that problems may arise.

[0029] A large, unintended external force can cause damage to a secondary battery located inside an electronic device. As a means to prevent problems from occurring, the laminate film and positive electrode that make up the battery, One method involves protecting the separator and negative electrode with a material that is less prone to deformation under force. ru.

[0030] However, the above method also makes it difficult to bend the rechargeable battery, so wearing a wristwatch or bracelet... It is undesirable to bend the rechargeable battery when using it, or when removing it from its installed state. stomach.

[0031] Inside a secondary battery, a structure is formed with a separator sandwiched between the positive and negative electrodes. Between the body and the surface temperature, within a range near the human skin surface temperature (30°C to 37°C), room temperature ( Thermoplastics that become softer than their state at approximately 25°C, for example, glass in the above temperature range. A thermoplastic resin having a transition point is provided.

[0032] When wearing a watch or bracelet around the body, the thermoplastic material inside the rechargeable battery may come into contact with the surface of human skin. It absorbs heat and becomes soft. This creates a problem where it becomes difficult to bend when wrapping. This does not occur. Thermoplastic objects are soft, so they are not susceptible to large, unintended external forces. This property protects against bending beyond the limit and the problem of the radius of curvature becoming too small. Although the effect may decrease, these problems do not occur when wearing the device because the wrist and arm are present.

[0033] When you remove a watch or bracelet from your body, the thermoplastic material inside the rechargeable battery absorbs the heat from the surface of your skin. Losing it, and then gradually hardening over time. When not wearing a watch or bracelet, unintentional The problem of bending beyond the limit due to a large external force, or the radius of curvature becoming too small, is not addressed. The probability of occurrence increases compared to when it is in use. At that time, because the thermoplastic material is in a hard state, secondary The property of protecting the battery has been restored.

[0034] Thermoplastics having a glass transition temperature in the range near skin surface temperature (30°C to 37°C) As an example of a glass resin, for instance, polyvinyl acetate (glass transition temperature T g It has a temperature of approximately 31°C. Polyvinyl acetate softens when heated to approximately 31°C. The glass transition temperature is within the above temperature range. Regardless of whether it possesses certain properties or not, any object that softens at or near skin surface temperature is acceptable, and the material is not limited. It will not be done.

[0035] The thermoplastic material is not limited to homopolymers, but may also be a copolymer.

[0036] Thermoplastics are substances whose glass transition temperature is adjusted by mixing plasticizers or other substances into a given material. That's fine.

[0037] Thermoplastics are placed inside secondary batteries, so there is a risk of them coming into contact with the electrolyte. Select a thermoplastic material that is resistant to the electrolyte, or ensure that the thermoplastic material does not come into contact with the electrolyte. Some ingenuity is needed. For example, thermoplastic materials that are resistant to electrolytes and have high thermal conductivity. It is best to cover it with a membrane.

[0038] The thermoplastic material is placed between the positive and negative electrodes, with a separator in between, and the outer casing. To efficiently transfer heat, thermoplastic materials are positioned close to the surface of human skin. You can do that. You can place them in multiple locations, but in that case, make sure that the heat is transferred simultaneously and to the same degree. It is preferable to do so.

[0039] Furthermore, the placement of thermoplastic objects is not limited to the inside of a secondary battery; for example, if the secondary battery is located inside It may be placed outside the electronic devices in place. The thermoplastic material will not come into direct contact with the surface of human skin. It may be a structure where one material is sandwiched in between, or it may be a structure where another material is sandwiched in between. In that case, the other material is Materials with high thermal conductivity are preferred.

[0040] One embodiment of the invention disclosed herein is a radius of curvature of 30 mm, preferably 10 m. This is a secondary battery that can be deformed to a shape having a curved surface of m. After being deformed into a shape with a curved surface of radius 30 mm, it is then transformed into a shape with a curved surface of radius 150 mm. It can also be deformed.

[0041] The radius of curvature of a surface will be explained using Figure 14. In Figure 14(A), the curved surface 1700 In the plane 1701 obtained by cutting the curve, a portion of the curve 1702 contained in the curved surface 1700 is an arc of a circle. By approximating this, the radius of the circle is set to the radius of curvature of 1703, and the center of the circle is set to the center of curvature of 1704. Figure 14(B) shows a top view of the curved surface 1700. Figure 14(C) shows the curved surface 1 on the plane 1701. The cross-sectional view of 700 is shown. When cutting a curved surface with a plane, the angle of the plane relative to the curved surface and The radius of curvature of the curve appearing in the cross-section will differ depending on the cutting position, but this specification, etc. Let's define the smallest radius of curvature as the radius of curvature of the surface.

[0042] A secondary battery in which two films form an outer casing, sandwiching the contents 1805, which include electrodes and electrolyte. When curved, the curvature of film 1801 on the side closer to the center of curvature 1800 of the secondary battery Radius 1802 is equal to the radius of curvature 1804 of film 1803 on the side furthest from the center of curvature 1800. It is also small (Figure 15(A)). In this case, the value of the radius of curvature closest to the center of curvature is used for the quadratic function. This is the radius of curvature of the battery.

[0043] Furthermore, the cross-sectional shape of a secondary battery is not limited to a simple arc shape, but may have a shape in which part of it is an arc. It is possible to create shapes such as the one shown in Figure 15(B), a wavy shape (Figure 15(C)), or an S-shape. It is also possible to do so. If the curved surface of the secondary battery has a shape with multiple centers of curvature, Among the radii of curvature at each of the centers of curvature, the two surfaces with the smallest radius of curvature The radius of curvature of the outer casing closest to the center of curvature can be changed to 30 mm, preferably 10 mm. It can be shaped.

[0044] The film used for the casing of secondary batteries is a metal film (aluminum, stainless steel, nickel). Steel, gold, silver, copper, titanium, nichrome, iron, tin, tantalum, niobium, molybdenum, zirconium Plastic foil made from metals or alloys such as nium and zinc (which can be used as metal foils), or organic materials. Film, a hybrid containing organic materials (such as organic resins and fibers) and inorganic materials (such as ceramics). Lid material film, carbon-containing inorganic film (carbon film, graphite film) A single-layer film or a laminated film consisting of multiple such films is used, selected from (etc.). The film is easy to emboss, and embossing can be used to form recesses or protrusions. This increases the surface area of ​​the film exposed to the outside air, resulting in superior heat dissipation.

[0045] Furthermore, the sealing structure of the secondary battery involves folding a single rectangular film in the middle, and the film A structure in which three of the four sides, excluding the side that will be folded, are fixed and closed with an adhesive layer, or two pieces The structure involves overlapping films and securing and sealing all four sides of the films with an adhesive layer.

[0046] The adhesive layer is a thermoplastic film material, a thermosetting adhesive, or an anaerobic adhesive, or an UV-curing adhesive. Adhesives such as light-curing adhesives and reaction-curing adhesives can be used. The materials used include epoxy resin, acrylic resin, silicone resin, and phenolic resin. It is possible to be there. [Effects of the Invention]

[0047] We can provide a rechargeable battery suitable for personal digital assistants or wearable devices. Or, a new We can provide energy storage devices.

[0048] Alternatively, we can provide electronic devices with novel structures. Specifically, we can create various external shapes. We can provide an electronic device with a novel structure that can do the following. Or, a new device with various external shapes. We can provide electronic devices with a standard structure and secondary batteries with a shape suitable for that structure.

[0049] A secondary battery, or an electronic device with a secondary battery inside, is subjected to a large, unintended external force. This solves the problem of equipment being bent beyond its limits, resulting in an excessively small radius of curvature.

[0050] Because the shape of the secondary battery can be freely designed, for example, by using a secondary battery with a curved surface... This increases the overall flexibility of electronic devices, making it possible to create electronic devices with a variety of designs. Furthermore, it eliminates the need to create wasted space in the gaps within curved electronic devices, and improves the appearance of the electronic devices. By placing a secondary battery inside the curved surface of an electronic device, along the curved surface of the device, space is created within the electronic device. It can be used for various purposes. For example, a flexible display unit having a certain area in an electronic device. If this is the case, the back of the display unit will have a gap of a certain area. One aspect of the present invention The next battery can effectively utilize gaps that have a certain amount of area, and by effectively utilizing the area, This will make it possible to create thin rechargeable batteries.

[0051] Therefore, it is possible to realize electronic devices with novel structures.

[0052] Furthermore, 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. Furthermore, other effects are... This will become clear from the description in the specification, drawings, claims, etc., and the specification, drawings Furthermore, it is possible to extract other effects from the descriptions in the claims and other documents. [Brief explanation of the drawing]

[0053] [Figure 1] This is a top view showing one aspect of the present invention and a schematic diagram illustrating the flow of current during charging of a secondary battery. [Figure 2] These are perspective views and cross-sectional views illustrating one aspect of the present invention. [Figure 3] This is a diagram of particles illustrating one aspect of the present invention. [Figure 4] These are a top view and a cross-sectional view showing one aspect of the present invention. [Figure 5] These are perspective views and cross-sectional views illustrating one aspect of the present invention. [Figure 6] This is a top view showing one aspect of the present invention. [Figure 7] This is an explanatory diagram of an embossing process showing one embodiment of the present invention. [Figure 8] This is a top view and a photograph illustrating one aspect of the present invention. [Figure 9] This is a top view and a perspective view showing one aspect of the present invention. [Figure 10] This is a perspective view showing one aspect of the present invention. [Figure 11] This is a diagram of a device for charging electronic equipment, illustrating one aspect of the present invention. [Figure 12] This is a diagram of an electronic device having a flexible energy storage device and an energy storage device, illustrating one aspect of the present invention. [Figure 13] This is a diagram illustrating a vehicle having a secondary battery, which represents one aspect of the present invention. [Figure 14] This is a diagram illustrating the radius of curvature of a surface. [Figure 15] This is a diagram illustrating the radius of curvature of a surface. [Figure 16] This is a perspective view showing one aspect of the present invention. [Modes for carrying out the invention]

[0054] The embodiments of the present invention will be described in detail below with reference to the drawings. However, the present invention is... Not limited to the following description, the form and details can be varied in various ways, as any person skilled in the art would know. This is easily understood. Furthermore, the present invention shall be interpreted as being limited to the contents of the embodiments described below. It's not something that can be done.

[0055] "Electrically connected" means connected via "something that has some kind of electrical effect". This includes connections. Here, "something that has some kind of electrical effect" refers to electrical signals between connected objects. There are no particular restrictions as long as it allows for the transfer of numbers.

[0056] The location, size, and extent of each component shown in the drawings, etc., are for the purpose of facilitating understanding. The location, size, and range may not be described. Therefore, the disclosed invention is not always Furthermore, it is not limited to the location, size, scope, etc., disclosed in drawings, etc.

[0057] Ordinal numbers such as "1st," "2nd," and "3rd" are added to avoid confusion of constituent elements. That is the case.

[0058] In this specification, "parallel" means that two straight lines are positioned at an angle of -10° or more and 10° or less. This refers to a state where something is positioned vertically. Therefore, it also includes cases where the angle is between -5° and 5°. This refers to a state where two straight lines are positioned at an angle of 80° to 100°. Therefore, This also includes cases where the angle is between 85° and 95°.

[0059] (Embodiment 1) In this embodiment, a structure is formed in which a separator is sandwiched between the positive electrode and the negative electrode inside, and this structure Between the outer casing and the surrounding material, the temperature is within the range of human skin surface temperature (30°C to 37°C) at room temperature. This example demonstrates the fabrication of a secondary battery that incorporates a thermoplastic material that becomes softer than its initial state.

[0060] Figure 1(A) shows an example of a schematic diagram of a secondary battery. Also, the internal structure enclosed by the outer casing of the secondary battery is shown. An example of the construction is shown in Figure 2(A).

[0061] A secondary battery 100 according to one aspect of the present invention has a positive electrode 101 and a separator 10 inside an outer casing 107. The secondary battery comprises at least 3, a negative electrode 102, a thermoplastic object 110, and an electrolyte. In terms of construction, there are various structures, but in this embodiment, a film is used to form the outer casing 107. Use.

[0062] The film used to form the exterior body 107 is a metal film (aluminum, stainless steel, nickel). Steel, gold, silver, copper, titanium, nichrome, iron, tin, tantalum, niobium, molybdenum, japonica Plastic foil made of metals or alloys (such as zinc, which can be used as metal foil), or organic materials. Film, a hybrid containing organic materials (such as organic resins and fibers) and inorganic materials (such as ceramics). Lid material film, carbon-containing inorganic film (carbon film, graphite film) A single-layer film or a laminated film consisting of multiple single-layer films selected from (etc.) is used.

[0063] In this embodiment, the thermoplastic material 110 covers the largest surface area of ​​the positive electrode 101. A sheet-like material is used. However, the thermoplastic material 110 and the positive electrode 101 have the largest surface area. The relationship between the larger and smaller surfaces is not limited to this. For example, the relative sizes of the two areas can be reversed. Furthermore, it is acceptable for the two to partially overlap. Also, in this embodiment, thermoplastic Object 110 is thicker than separator 103. Also, thermoplastic object 110 is It may have slits. Also, the thermoplastic object 110 is not limited to a rectangle, but may have four corners. It may also be a rounded shape. If the thermoplastic object 110 has sharp corners, secondary electricity When the pond is bent, there is a risk that the corner will damage the film that forms the outer casing, therefore thermoplastic By chamfering the corners of the body 110, a reliable secondary battery can be provided. The material of the plastic object 110 can be any material that softens at or near skin surface temperature.

[0064] Furthermore, if the surface of the thermoplastic object 110 is smooth, then the contact with the surface of the thermoplastic object 110 The internal structure and the sliding parts with the outer casing also contribute to providing rechargeable batteries that are resistant to repeated bending. can.

[0065] The positive electrode 101 has a positive electrode active material layer on one or both sides of the current collector (aluminum, etc.). This includes those provided with a negative electrode 102, which has a negative electrode active material layer on one or both sides of the current collector (copper, etc.). This includes those that have the following features. Also, the positive electrode 101 is electrically connected to the positive electrode lead 104. The negative electrode 102 is electrically connected to the negative electrode lead 105. The positive electrode lead 104 is also electrically connected to the negative electrode lead 105. The negative electrode lead 105 is also called a lead electrode or lead terminal. The positive electrode lead 104 And a portion of the negative electrode lead 105 is located on the outside of the outer casing. Also, the charging of the secondary battery 100 Electricity is supplied and discharged via the positive lead 104 and the negative lead 105.

[0066] Here, we will use Figure 1(B) to explain the current flow during the charging of a secondary battery. When a secondary battery is considered as a closed circuit, the movement of lithium ions and the flow of current are in the same direction. Yes. In lithium-ion secondary batteries, the anode and cathode are used during charging and discharging. The cathode is swapped, and the oxidation and reduction reactions are reversed, so the reaction potential changes. The electrode with the higher potential is called the positive electrode, and the electrode with the lower reaction potential is called the negative electrode. Therefore, in this specification Therefore, whether charging or discharging, or even when applying a reverse pulse current, Even when an electric current is flowing, the positive electrode is called the "positive electrode" or "+ electrode (plus electrode)," and the negative electrode is called the "negative electrode." We will refer to this as the "negative electrode" or "- electrode (minus electrode)." In relation to oxidation and reduction reactions... If we use the terms anode and cathode, then during charging and discharging, This could be reversed and cause confusion. Therefore, the anode and cathode The term (cathode) will not be used in this specification. When using the terms cathode, specify whether it is during charging or discharging, and indicate the positive electrode ( We will also indicate whether it corresponds to the negative (last) or last (minus) pole.

[0067] The charger is connected to the two terminals shown in Figure 1(B), and the secondary battery 100 is charged. As battery 100 charges, the potential difference between the electrodes increases. In Figure 1(B), secondary battery 1 The current flows from the external terminal of 00 (positive lead 104) towards the positive current collector (positive electrode 101), and In the secondary battery 100, current flows from the positive electrode 101 to the negative electrode 102, and from the negative electrode to the secondary battery 1 The direction of the current flowing towards the external terminal (negative lead 105) of 00 is defined as the positive direction. In other words, the direction in which the charging current flows is considered the direction of the current.

[0068] In this embodiment, for the sake of simplicity, a set of positive electrode 101 and negative electrode 102 are enclosed in an outer casing. The example shown is for storage in 107, but to increase the capacity of the secondary battery, multiple sets of positive electrodes are used. 101 and the negative electrode 102 may be housed in the outer casing 107.

[0069] As shown in Figure 2(A), the exterior body 107 contains a thermoplastic material 110 and a positive electrode 101. This shows an example in which the separator 103 and the negative electrode 102 are arranged. Note that Figure 2(A) For simplification, the outer casing 107, positive lead 104, and negative lead 105 are not shown. .

[0070] Figure 2(A-1) is a cross-sectional view of Figure 2(A) taken along the dashed line A-A'. ) is a cross-sectional view obtained by cutting Figure 2(A) along the dashed line B-B'. On the thermoplastic material 110, A positive electrode 101, a separator 103, and a negative electrode 102 are provided. Cross section A-A' and In cross-section B-B', the thermoplastic material 110 has the widest width. For example, about 5%. Thermoplastic material 110 is made to be slightly larger and wider than material 103.

[0071] Furthermore, in cross-sections A-A' and B-B', the negative electrode 102 is slightly wider than the positive electrode 101. Wide. The negative electrode 102 is made slightly larger than the positive electrode 101, for example, about 5% wider. ru.

[0072] Furthermore, in cross-sections A-A' and B-B', the separator 103 is further from the negative electrode 102. It's a little wider. Separator 103 is slightly larger than negative electrode 102, for example, about 5% wider. I am creating it.

[0073] By forming the thermoplastic object 110 to be slightly larger than the separator 103, unintended A large external force can cause a secondary battery, or an electronic device in which a secondary battery is placed, to be limited It can be bent beyond the limit, solving the problem of the radius of curvature becoming too small. However, thermoplastic The relative sizes of the plastic body 110 and the separator 103 are essential components for achieving the above effect. It's not that there is a specific relationship between the two areas; the relative sizes of the two areas can be reversed. Furthermore, if the two partially overlap... It's fine if the relationship is compatible. It can be changed due to the design requirements of the secondary battery or electronic device. That is the case.

[0074] During charging of the secondary battery, lithium ions are released from the positive electrode 101 and inserted into the negative electrode 102. However, by forming the negative electrode 102 to be slightly larger than the positive electrode 101, lithium can be added to the negative electrode 102. This allows for efficient insertion of lithium ions and suppression of lithium deposition on the surface of the negative electrode 102. Cut.

[0075] As materials for forming separator 103, cellulose (paper), nanocell roll, Cellulose nanofiber, polypropylene (PP), polyethylene (PE), polybutene Nylon, polyester, polysulfone, polyacrylonitrile, polyvinyl fluoride Porous insulators such as den, tetrafluoroethylene, etc. can be used. Also, glass fibers Nonwoven fabrics such as fiberglass, or diaphragms made of a composite of glass fibers and polymer fibers may also be used.

[0076] In this embodiment, the configuration of the secondary battery is such that, for example, the thickness of the separator 103 is approximately 15 μm. m or more and 30 μm or less, the thickness of the current collector of positive electrode 101 is approximately 10 μm or more and approximately 40 μm or less, positive electrode The thickness of the active material layer is approximately 50 μm to 100 μm, and the thickness of the negative electrode active material layer is approximately 50 μm or less. The thickness of the upper electrode is approximately 100 μm or less, and the thickness of the current collector of the negative electrode 102 is approximately 5 μm to approximately 40 μm.

[0077] Furthermore, Figure 2(A) shows an example where the separator 103 is in sheet form, but a bag is also used. You may use a shape like this. Alternatively, you can bend one separator and place a straight piece between the bent separators. The pole (or negative pole) may be positioned inside the outer casing 107.

[0078] Figure 16(A) shows an example using a bag-shaped separator 103. Bag-shaped separator 103 Insert the positive electrode 101 through the opening, and then close the opening by methods such as heat welding. Oh, when heat welding, in addition to welding all the edges of the bag in a linear fashion, there are also welding points every 1 cm along the edges, The non-welded areas may be repeatedly welded in a dotted line pattern. This will create a bag-shaped separator. The electrolyte can easily permeate the positive electrode 101 inside the 103.

[0079] In Figure 16(B), a bag-shaped separator 103 is used to connect two positive electrodes 101a and 101b. An example of creating two negative electrodes 102a and 102b is shown. Two are placed in one bag-shaped separator 103. The positive electrodes 101a and 101b are inserted.

[0080] The positive electrodes 101a and 101b, and the negative electrodes 102a and 102b, have active material on both their front and back surfaces. (Hereafter also referred to as double-sided coating) is possible, but in the structure shown in Figure 16(B), Active material is provided on one side of each of poles 101a and 101b (hereinafter also referred to as single-sided coating). Alternatively, a structure can be created where one side of each side without the active material faces the other. When the surfaces of the positive electrode active material are coated on both sides (for example, when positive electrode 101a and positive electrode 101b are coated on both sides) In the case where the active material surface of positive electrode 101a and the active material surface of positive electrode 101b are in contact, or Material surface and metal surface (for example, when the positive electrode 101a is coated on both sides, positive electrode 101 Compared to the case where the active material surface of a and the metal surface of positive electrode 101b are in contact, the adjacent positive electrode Metal surfaces come into contact with each other (for example, the metal surface of positive electrode 101a and the metal surface of positive electrode 101b). In this case, the coefficient of static friction becomes low. When a secondary battery deforms, the reaction generated inside the battery The force can be mitigated by sliding between the contact surfaces of the adjacent positive electrode metal surfaces.

[0081] In the structure shown in Figure 16(B), the negative electrodes 102a and 102b are coated on one side, and the negative electrode 102a One side without active material faces the thermoplastic object 110, and the negative electrode 102b does not have active material. It is also possible to have a structure where one side faces the surface of the outer casing, which is not shown. Active material surface ( For example, when the negative electrode 102a is coated on both sides, the active material surface of the negative electrode 102a and heat When the plastic object 110 is in contact or the surface of the active material (for example, when the negative electrode 102b is coated on both sides) In this case, compared to when the active material surface of the negative electrode 102b and the outer casing are in contact, the metal surface When a surface (for example, the metal surface of the negative electrode 102a) and the thermoplastic object 110 come into contact, or when the metal surface When the metal surface of the negative electrode 102b (for example) is in contact with the outer casing, the coefficient of static friction becomes low. When a secondary battery deforms, the stress generated inside the battery is transmitted between the metal surface and the thermoplastic material. 10 can slide and relax on the surfaces it contacts and on the surfaces where the metal surface and the exterior body come into contact. .

[0082] Furthermore, the position of the thermoplastic object 110 is not limited to that shown in Figure 2(A). For example, in Figure 2(B) As shown, a thermoplastic object 110 may be provided on the side in contact with the negative electrode 102. Electronic equipment design Accordingly, to efficiently transfer heat to the thermoplastic object 110, it is positioned closer to the surface of human skin. A thermoplastic object should be placed in the area shown in Figure 2(B). Also, the cross section A-A' in Figure 2(B-1 ), and section B-B' are shown in Figure 2 (B-2). The design size concepts are shown in Figure 2 ( This is the same as A-1) and Figure 2(A-2).

[0083] Also, the thermoplastic object 110 is not limited to one, and a plurality of them may be used. For example, in Fig. 2(C) As shown, a configuration having a positive electrode 1 01, a separator 103, and a negative electrode 102 between the first thermoplastic object 110a and the second thermoplastic object 110b may be used. In that case, they may be arranged so that heat is transmitted to a plurality of thermoplastic objects equally. Also, the cross-section A -A' of Fig. 2(C) is shown in Fig. 2(C-1), and the cross-section B-B' is shown in Fig. 2(C-2). The design size concepts are the same as those in Fig. 2(A-1) and Fig. 2(A-2), respectively.

[0084] As the positive electrode active material used in the positive electrode active material layer of the secondary battery 100, there are composite oxides having an olivine-type crystal structure, a layered rock salt-type crystal structure, or a spinel-type crystal structure, etc. As the positive electrode active material, for example, compounds such as LiFeO2, LiCoO2, LiNiO2, LiMn2O4, V2 O5, Cr2O5, MnO2, etc. are used.

[0085] Or, a composite material (general formula LiMPO4 (M is one or more of Fe(II), Mn(II), Co(II), 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 less than or equal to 1, 0 < c < 1, 0 < d < 1, 0 < e < 1), LiFe f Ni g C o h Mn i PO4 (f + g + h + i is less than or equal to 1, 0 < f < 1, 0 < g < 1, 0 < h < 1, 0 <i < 1) and other lithium compounds can be mentioned.

[0086] Or, a composite material such as the general formula Li 2-j MSiO4 (M is one or more of Fe(II), Mn(II ), Ni(II), 0 ≤ j ≤ 2) can be used. General formula L i 2-j MSiO4's representative examples include Li 2-j FeSiO4, Li 2-j NiSiO 4, Li 2-j CoSiO4, Li 2-j MnSiO4, Li 2-j Fe k Ni l SiO 4, Li 2-j Fe k Co l SiO4, Li 2-j Fe k Mn l SiO4, Li 2-j N i k Co l SiO4, Li 2-j Ni k Mn l SiO4 (k + l is less than or equal to 1, 0 < k < 1, 0 < l < 1), Li 2-j Fe m Ni n Co q SiO4, Li 2-j Fe m Nin Mn q SiO4, Li 2-j Ni m Co n Mn q SiO4 (where m + n + q is less than or equal to 1, 0 < m < 1, 0 < n < 1, 0 < q < 1), Li 2-j Fe r Ni s Co t Mn u SiO4 (r + s + t + u is less than or equal to 1, 0 < r < 1, 0 < s < 1, 0 < t < 1, 0 < u < 1), etc., lithium compounds can be mentioned.

[0087] 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, the NASICON-type compound can be used. Examples of NASICON-type compounds include Fe2(MnO4) 3, Fe2(SO4)3, Li3Fe2(PO4)3, etc. Also, as the positive electrode active material , compounds represented by the general formula Li2MPO4F, Li2MP2O7, Li5MO4 (M = Fe, Mn) , perovskite-type fluorides such as NaFeF3, FeF3, metal chalcogenides (sulfides, selenides, tellurides) such as TiS2, Mo S2, etc., oxides having a reverse spinel-type crystal structure such as LiMVO4, vanadium oxide-based (V2O5, V6O , L 13 iV3O8, etc.), manganese oxides, organic sulfur compounds, etc. can be used. Also, as the positive electrode active material, lithium manganese represented by the composition formula Li

[0088] which can be represented by a Mn b M c O d ​A composite oxide can be used. Here, element M is derived from a source other than lithium or manganese. A selected metal element, or preferably silicon or phosphorus, is used, and it is nickel. This is even more preferable. Also, when measuring the entire lithium manganese composite oxide particle, discharge The conditions <a / (b+c)<2、かつc>are 0 and 0.26 ≤ (b+c) / d < 0.5. It is preferable to add. Furthermore, the metal, silicon, and other elements of the lithium manganese composite oxide particles as a whole are preferable. The composition of phosphorus and other elements can be measured, for example, using ICP-MS (inductively coupled plasma mass spectrometer). It is possible. Also, the oxygen composition of the entire lithium manganese composite oxide particle is, for example, ED It is possible to measure using X-ray (energy-dispersive X-ray spectroscopy). Also, ICP- In conjunction with MS analysis, valence evaluation using molten gas analysis and XAFS (X-ray absorption fine structure) analysis is employed. It can be determined by having it. Furthermore, lithium manganese composite oxide is at least Li This refers to oxides containing thium and manganese, as well as chromium, cobalt, aluminum, nickel, Iron, magnesium, molybdenum, zinc, indium, gallium, copper, titanium, niobium, cyanoacrylate It may contain at least one element selected from the group consisting of lycon and phosphorus. stomach.

[0089] Furthermore, in order to achieve high capacity, the crystal structure, crystal orientation, or oxygen content of the surface and core are determined. It is preferable to use a lithium manganese composite oxide having regions with different concentrations. To obtain a lithium manganese composite oxide, the composition formula is Li a Mn b Ni c O d (1.6 The ranges should be (≤ a ≤ 1.848, 0.19 ≤ c / b ≤ 0.935, 2.5 ≤ d ≤ 3). ​Li is preferable. 1.68 Mn 0.8062 Ni 0.318 The chemical formula for O3 is It is particularly preferable to use a lithium manganese composite oxide. Li 1.68 Mn 0.8062 Ni 0.318 Lithium magnesium, represented by the chemical formula O3 MnCO3 is a compound oxide in which the ratio (molar ratio) of the raw materials is Li2CO3:MnCO3: Lithium manganese formed by setting NiO = 0.84:0.8062:0.318 This refers to a lithium manganese composite oxide. Therefore, the lithium manganese composite oxide has the compositional formula Li 1.68 M n 0.8062 Ni 0.318 It is represented as O3, but the composition may deviate from this.

[0090] Lithium manganese composite oxides having regions with different crystal structures, crystal orientations, or oxygen content. An example of a cross-sectional view of a particle is shown in Figure 3.

[0091] As shown in Figure 3(A), there are regions with different crystal structures, crystal orientations, or oxygen content. The thium manganese composite oxide consists of a first region 331, a second region 332, and a third region 3 It is preferable to have 33. The second region 332 is at least outside the first region 331. It also touches a part of it. Here, "outside" refers to the area closer to the surface of the particle. Also, the third region Region 333 has a region that coincides with the surface of the particles having lithium manganese composite oxide. It is preferable.

[0092] Furthermore, as shown in Figure 3(B), the first region 331 is an area not covered by the second region 332. It may have a region. Also, the second region 332 has a region that is not covered by the third region 333. It is also possible to have a region where the third region 333 is adjacent to the first region 331. Good. Also, the first region 331 is located in either the second region 332 or the third region 333. It may also have areas that are not covered.

[0093] The second region 332 preferably has a different composition from the first region 331.

[0094] For example, the composition of the first region 331 and the second region 332 are measured separately, and the composition of the first region 331 The first region has manganese, element M and oxygen, and the second region 332 has manganese, element M and oxygen The first region 331 has the atomic ratio of manganese, element M, and oxygen as b1:c1:d Represented by 1, the atomic ratio of manganese, element M, and oxygen in the second region 332 is b2:c2 Let's explain the case represented by :d2. Note that the first region 331 and the second region 332 Each composition is determined, for example, by EDX (energy dispersion) using TEM (transmission electron microscope). It can be measured by type X-ray analysis. When measured by EDX, lithium is in the composition Because measurement is difficult up to that point, the difference in composition between the first region 331 and the second region 332 is due to lithium Let's discuss elements other than mu. Here, d1 / (b1+c1) is preferably 2.2 or greater. It is more preferable that the value is 2.3 or higher, and even more preferable that it is 2.35 or higher and 3 or lower. Furthermore, d2 / (b2+c2) is preferably less than 2.2, and preferably less than 2.1. It is more preferable that it is 1.1 or more and 1.9 or less. Also in this case Also, the entire lithium manganese composite oxide particle including the first region 331 and the second region 332. The composition is preferably such that the aforementioned 0.26 ≤ (b+c) / d < 0.5 is satisfied.

[0095] For example, the composition of the first region 331 and the second region 332 are measured separately, and the composition of the first region 331 The first region contains lithium, manganese, element M, and oxygen, and the second region 332 contains lithium, manganese. It has elements M and oxygen, and the first region 331 has lithium, manganese, element M, and The atomic ratio of oxygen is expressed as a1:b1:c1:d1, and lithium and man are in the second region 332. Consider the case where the atomic ratio of cancer, element M, and oxygen is expressed as a²:b²:c²:d². Let me explain. Note that the composition of the first region 331 and the second region 332 are, for example, TE Measurement using EDX (energy-dispersive X-ray spectroscopy) with a transmission electron microscope (M). This is possible. However, measuring lithium composition can be difficult using EDX. Therefore, below, the difference in composition between the first region 331 and the second region 332 is due to elements other than lithium. Let's discuss the primes. Here, d1 / (b1+c1) is preferably 2.2 or greater, and preferably 2.3 or greater. It is more preferable that it is 2.35 or more and 3 or less. Also, d 2 / (b²+c²) is preferably less than 2.2, and more preferably less than 2.1. Furthermore, it is even more preferable that it be between 1.1 and 1.9. Also in this case, the first The overall composition of the lithium manganese composite oxide particles, including region 331 and the second region 332, is as follows: It is preferable that the condition 0.26 ≤ (b+c) / d < 0.5 is satisfied.

[0096] Furthermore, the manganese contained in the second region 332 is different from the manganese contained in the first region 331. It may have a valency. Also, the element M in the second region 332 is the same as the element in the first region 331. It may have a different valency than the element M it contains.

[0097] More specifically, the first region 331 is lithium manganese having a layered rock salt-type crystalline structure. It is preferable that it be a composite oxide. Furthermore, the second region 332 has a spinel-type crystal structure. It is preferable that it be a lithium manganese composite oxide.

[0098] Here, if there is a spatial distribution of the composition of each region or the valence of elements, for example, multiple locations The composition and valency of each are evaluated, their average values ​​are calculated, and these are also used as the composition and valency of the region. stomach.

[0099] Furthermore, a transition layer may be provided between the second region 332 and the first region 331. A transition zone is, for example, a region where the composition changes continuously or stepwise. A transition layer is a region in which the crystal structure changes continuously or stepwise. This is a region where the lattice constant of the crystal changes continuously or stepwise. Alternatively, it is the second region 3. A mixed layer may be present between region 32 and the first region 331. Here, the mixed layer is, for example, different This refers to the case where two or more crystals having the same crystal orientation are mixed. Alternatively, a mixed layer is, for example, This refers to the case where two or more crystals with different crystal structures are mixed. Alternatively, a mixed layer is, For example, this refers to the case where two or more crystals with different compositions are mixed.

[0100] In the third region 333, carbon or a metallic compound can be used. Here, as a metallic compound For example, cobalt, aluminum, nickel, iron, manganese, titanium, zinc, lithium Examples include oxides and fluorides of these metals. It can be listed.

[0101] The third region 333 is particularly preferably carbon, among the above. Carbon is electrically conductive. Because of the high cost, carbon-coated particles can be used as electrodes in secondary batteries, for example, the resistance of the electrodes The resistance can be lowered. Also, because the third region 333 has carbon, the third region The second region 332, which is in contact with 333, can be oxidized. Also, the third region 333 is It may contain graphene, it may contain graphene oxide, and it may contain reduced graphene oxide. It may be done. Graphene and reduced graphene oxide have high conductivity. It possesses excellent electrical properties, as well as superior physical properties such as high flexibility and mechanical strength. Furthermore, it can efficiently coat lithium manganese composite oxide particles.

[0102] The third region 333 contains carbon, including graphene, which is used to form lithium manganese This can improve the cycle characteristics of secondary batteries that use composite oxides as the cathode material.

[0103] The thickness of the carbon-containing layer is preferably between 0.4 nm and 40 nm.

[0104] Furthermore, lithium manganese composite oxides, for example, have an average particle diameter of primary particles of 5 nm or more. It is preferable that the thickness is 0 μm or less, and more preferably 100 nm to 500 nm. It is also good. 2 / g or more 15m 2 It is preferable that it is less than or equal to / g. Also, The average particle diameter of the next particles is preferably 5 μm or more and 50 μm or less. This involves observation using SEM (scanning electron microscope) or TEM, or laser diffraction / scattering methods. The particle size can be measured using a particle size analyzer or similar device. The specific surface area can also be measured by the gas adsorption method. It can be measured.

[0105] Furthermore, the positive electrode active material layer contains, in addition to the positive electrode active material mentioned above, a binder to enhance the adhesion of the active material. The material may contain a binder, a conductive additive to enhance the conductivity of the positive electrode active material layer, etc.

[0106] Furthermore, the carrier ions include alkali metal ions other than lithium ions, and alkaline earth metal ions. In the case of ions, instead of lithium, an alkali metal (for example, sodium) can be used as the positive electrode active material. (e.g., um and potassium), alkaline earth metals (e.g., calcium, strontium, varium) (Metallic acid, beryllium, magnesium, etc.) may also be used.

[0107] The electrolyte is a substance that, as an electrolyte, allows carrier ions to move and is also a carrier ion. Materials containing lithium ions are used. Typical examples of electrolytes include LiPF6 and LiCl. O4, LiAsF6, LiBF4, LiCF3SO3, Li(CF3SO2)2N, Li There are lithium salts such as (C2F5SO2)2N. These electrolytes can be used individually. It is also acceptable to use two or more types in any combination and ratio.

[0108] Furthermore, a material that allows carrier ions to move is used as the solvent for the electrolyte. As such, aprotic organic solvents are preferred. Typical examples of aprotic organic solvents include: Ethylene carbonate (EC), propylene carbonate, dimethyl carbonate, die Dichloroethylene carbonate (DEC), γ-butyrolactone, acetonitrile, dimethoxyethane These include tetrahydrofuran, and one or more of these can be used. By using a polymer material that gels as the solvent for the electrolyte, safety against leakage, etc. It is increasing. In addition, it is possible to make secondary batteries thinner and lighter. Examples include silicone gel, acrylic gel, acrylonitrile gel, polyethylene Examples include phosphate gels, polypropylene oxide gels, and fluorine polymer gels. Furthermore, one ionic liquid (a room-temperature molten salt) that is flame-retardant and non-volatile is used as the solvent for the electrolyte. Alternatively, by using multiple units, internal temperature rise due to internal short circuits or overcharging of the secondary battery may occur. This can also prevent secondary batteries from rupturing or catching fire. Note that ionic liquids are in a fluid state. It is a salt and has high ion mobility (conductivity). Also, ionic liquids are composed of cations and anions. It includes. As an ionic liquid, it contains ethylmethylimidazolium (EMI) cation. On liquid, or N-methyl-N-propylpiperidinium (PP 13 ) Contains cations Examples include ionic liquids.

[0109] In addition, instead of an electrolyte, a solid electrolyte containing inorganic materials such as sulfides and oxides, or PEO, can be used. Solid electrolytes containing polymer materials such as polyethylene oxide can be used. When using a solid electrolyte, the installation of separators and spacers becomes unnecessary. Also, the entire battery Because it can be solidified, the risk of leakage is eliminated, dramatically improving safety.

[0110] The negative electrode active material used in the negative electrode active material layer of secondary battery 100 is lithium dissolved and deposited, This allows the use of materials that enable the insertion and removal of lithium ions, such as lithium metal and carbon-based materials. Materials, alloy materials, etc., can be used.

[0111] Lithium metal has a low oxidation-reduction potential (-3.045V compared to a standard hydrogen electrode), and its weight and They have a high specific capacity per unit volume (3860mAh / g and 2062mAh / cm³, respectively). 3 ) Therefore, it is preferable.

[0112] Examples of carbon-based materials include graphite, graphitizable carbon (soft carbon), non-graphitizable carbon (hard carbon), carbon nanotubes, graphene, carbon black, and the like.

[0113] Examples of graphite include artificial graphite such as mesocarbon microbeads (MCMB), coke-based artificial graphite, and pitch-based artificial graphite, and natural graphite such as spheroidized natural graphite.

[0114] When lithium ions are inserted into graphite (when forming a lithium-graphite intercalation compound), graphite exhibits a potential as low as that of metallic lithium (0.1 V or more and 0.3 V or less vs. Li / Li +

[0115] ). As a result, lithium-ion secondary batteries can exhibit a high operating voltage. Furthermore, graphite has advantages such as a relatively high capacity per unit volume, small volume expansion, low cost, and high safety compared to metallic lithium, so it is preferable. As the negative electrode active material, alloy-based materials capable of performing charge and discharge reactions through alloying and dealloying reactions with lithium can also be used. When the carrier ion is a lithium ion, examples of alloy-based materials include materials containing at least one of Al, Si, Ge, Sn, Pb, Sb, Bi, Ag, Au, Zn, Cd, In, Ga, and the like. Such elements have a large capacity with respect to carbon, and in particular, silicon has a theoretically extremely high capacity of 4200 mAh / g. 3, FeSn2, CoSn2, Ni3Sn2, Cu6Sn5, Ag3Sn, Ag3Sb,​​ Ni2MnSb, CeSb3, LaSn3, La3Co2Sn7, CoSb3, InSb , SbSn, etc. Note that SiO refers to a powder of silicon oxide containing a silicon-rich part and can also be expressed as SiO y (2 > y > 0). For example, SiO includes a material containing one or more selected from Si2O3, Si3O4, or Si2O, or a mixture of Si powder and silicon dioxide SiO2. Also, SiO may contain other elements (carbon, nitrogen, iron, aluminum , nickel, copper, titanium, calcium, manganese, etc.). That is, SiO refers to a material containing a plurality selected from single crystal Si , amorphous Si, polycrystalline Si, Si2O3, Si3O4, Si2O, SiO2, and SiO is a colored material. SiO that is not SiO (X is 2 or more) is colorless and transparent or white and can be distinguished. However, x after manufacturing a secondary battery using SiO as the negative electrode active material and repeating charge and discharge, etc., when SiO is oxidized, it may be transformed into SiO2.

[0116]

[0117] 12 x

[0118] 3-x

[0119] x 2.6 Co 0.4 N3 exhibits a large charge-discharge capacity (900 mAh / g, 1890 mAh / cm3) and is preferable. It is preferable.

[0118] When using a complex nitride of lithium and a transition metal, since the negative electrode active material contains lithium ions, it can be combined with materials such as V2O5 and Cr3O8 that do not contain lithium ions as the positive electrode active material, which is preferable. In addition, even when using a material containing lithium ions as the positive electrode active material, by previously desorbing the lithium ions contained in the positive electrode active material, a complex nitride of lithium and a transition metal can be used as the negative electrode active material. It can be combined with materials such as V2O5 and Cr3O8 that do not contain lithium ions as the positive electrode active material, which is preferable. In addition, even when using a material containing lithium ions as the positive electrode active material, by previously desorbing the lithium ions contained in the positive electrode active material, a complex nitride of lithium and a transition metal can be used as the negative electrode active material. Also, even when using a material containing lithium ions as the positive electrode active material, by previously desorbing the lithium ions contained in the positive electrode active material, a complex nitride of lithium and a transition metal can be used as the negative electrode active material. Also, even when using a material containing lithium ions as the positive electrode active material, by previously desorbing the lithium ions contained in the positive electrode active material, a complex nitride of lithium and a transition metal can be used as the negative electrode active material. It can be used as the negative electrode active material.

[0119] In addition, a material that undergoes a conversion reaction can also be used as the negative electrode active material. For example, transition metal oxides such as cobalt oxide (CoO), nickel oxide (NiO), and iron oxide (FeO) that do not undergo an alloying reaction with lithium can be used as the negative electrode active material. As materials that undergo a conversion reaction, further, oxides such as Fe2O3, CuO, Cu2O, RuO2, and Cr2O3, sulfides such as CoS, NiS, and CuS, nitrides such as Zn3N2, Cu3N, and Ge3N4, phosphides such as NiP2, FeP2, and CoP3, and fluorides such as FeF3 and BiF3 also occur. Since the potential of the above fluorides is high, it can also be used as the positive electrode active material. For example, transition metal oxides such as cobalt oxide (CoO), nickel oxide (NiO), and iron oxide (FeO) that do not undergo an alloying reaction with lithium can be used as the negative electrode active material. As materials that undergo a conversion reaction, further, oxides such as Fe2O3, CuO, Cu2O, RuO2, and Cr2O3, sulfides such as CoS, NiS, and CuS, nitrides such as Zn3N2, Cu3N, and Ge3N4, phosphides such as NiP2, FeP2, and CoP3, and fluorides such as FeF3 and BiF" It can be used as the negative electrode active material. It can also occur with sulfides such as CoS, NiS, and CuS, nitrides such as Zn3N2, Cu3N, and Ge3N4, phosphides such as NiP2, FeP2, and CoP3, and fluorides such as FeF3 and BiF3. Since the potential of the above fluorides is high, it can also be used as the positive electrode active material. 3, etc., sulfides such as CoS, NiS, and CuS, nitrides such as Zn3N2, Cu3N, and Ge3N4, phosphides such as NiP2, FeP2, and CoP3, and fluorides such as FeF3 and BiF3 also occur. Since the potential of the above fluorides is high, it can also be used as the positive electrode active material. 0.89 It can also occur with sulfides such as CoS, NiS, and CuS, nitrides such as Zn3N2, Cu3N, and Ge3N4, phosphides such as NiP2, FeP2, and CoP3, and fluorides such as FeF3 and BiF" 4, etc., phosphides such as NiP2, FeP2, and CoP3, and fluorides such as FeF3 and BiF3 also occur. Since the potential of the above fluorides is high, it can also be used as the positive electrode active material. 4, etc., phosphides such as NiP2, FeP2, and CoP3, and fluorides such as FeF3 and BiF3 also occur. Since the potential of the above fluorides is high, it can also be used as the positive electrode active material. It can also be used as the positive electrode active material.

[0120] In addition, the negative electrode active material layer may have, in addition to the above-described negative electrode active material, a binder (binder) for enhancing the adhesion of the active material, a conductive aid for enhancing the conductivity of the negative electrode active material layer, and the like. In addition, the negative electrode active material layer may have, in addition to the above-described negative electrode active material, a binder (binder) for enhancing the adhesion of the active material, a conductive aid for enhancing the conductivity of the negative electrode active material layer, and the like.

[0121] In this embodiment, an example of a small battery used in a portable information terminal or the like is shown, but it is not particularly limited. Furthermore, it can be applied to large batteries installed in vehicles and other similar devices.

[0122] In this embodiment, one aspect of the present invention has been described. Or, other embodiments may be described. In this context, one aspect of the present invention will be described. However, this aspect of the present invention is not limited to these. Not done. In other words, various aspects of the invention are described in this embodiment and other embodiments. Therefore, one aspect of the present invention is not limited to a specific aspect. For example, one aspect of the present invention As an example, an example of its application to lithium-ion secondary batteries has been shown, but one aspect of the present invention is this This is not limited to the present invention. Depending on the circumstances, one aspect of the present invention may apply to various situations. Secondary batteries, lead-acid batteries, lithium-ion polymer secondary batteries, nickel-metal hydride batteries, nickel Lu-cadmium batteries, nickel-iron batteries, nickel-zinc batteries, silver oxide-zinc batteries Pond, solid battery, air battery, zinc-air battery, lithium-air battery, primary battery, capacitor, Other examples include electric double-layer capacitors, ultracapacitors, supercapacitors, and lithium capacitors. It may also be applied to ion capacitors, etc. Or, for example, depending on the circumstances, or Depending on the circumstances, one aspect of the present invention does not need to be applied to lithium-ion secondary batteries. For example, one aspect of the present invention has shown an example in which the energy storage device is modified, but The present invention is not limited to these examples. Depending on the circumstances, or depending on the situation, one aspect of the present invention may be used. The energy storage device may be configured in a way that does not deform, or in a way that does not bend. Alternatively, depending on the circumstances, in one aspect of the present invention, the energy storage device is a flat plate The configuration may remain as is. Also, for example, in one aspect of the present invention, a thermoplastic may be added to the energy storage device. An example in which a sexual object 110 or the like is provided has been shown, but one aspect of the present invention is not limited thereto. Depending on the circumstances, or depending on the situation, in one aspect of the present invention, the energy storage device may have various properties. An object having the above may be provided. Alternatively, depending on the circumstances, the present invention may be provided. In one embodiment, the thermoplastic material may have properties other than thermoplasticity.

[0123] This embodiment can be freely combined with other embodiments.

[0124] (Embodiment 2) Embodiment 1 showed an example using a sheet-like thermoplastic material, but in this embodiment, This example uses a thermoplastic object with a different shape than that of the first implementation method, and also shows a different installation location.

[0125] Figure 4(A) shows an example of a schematic diagram of a secondary battery. Also, the internal structure enclosed by the outer casing of the secondary battery is shown. An example of the construction is shown in Figure 4(B). Note that in Figure 4, the same reference numerals are used for parts common to Figure 1. I will explain it in detail, and for the sake of simplicity, I will omit the detailed explanation here.

[0126] A secondary battery 400 according to one aspect of the present invention has a positive electrode 101 and a separator 10 inside an outer casing 107. 3, the negative electrode 102, the first thermoplastic object 410a, the second thermoplastic object 410b, It contains at least an electrolyte.

[0127] In this embodiment, the first thermoplastic object 410a and the second thermoplastic object 410b are used as A rod-shaped separator, thicker than separator 103, is used.

[0128] As shown in Figures 4(A) and 4(B), the first thermoplastic object 410a and the second thermoplastic object The positive electrode 101, separator 103, and negative electrode 102 are positioned between the body 410b and the positive electrode 101, separator 103, and negative electrode 102. Place it.

[0129] Furthermore, the outer edge of the outer casing 107 is bonded by heat compression. The bonding area 411 is bonded by heat compression. This is the bonded area. The film used for the exterior body 107 has a layer made of polypropylene. Only the portion of the film surface that is heat-pressed becomes the adhesive area.

[0130] The first thermoplastic material 410a and the second thermoplastic material 410b are bonded to the adhesive region 411 and the positive electrode. When placed between the laminate of 101, separator 103, and negative electrode 102, the outer casing 107 A cross-sectional shape that gently reduces the step difference between the region overlapping with the laminate and the region overlapping with the adhesive region 411. To make it into a shape.

[0131] The materials used for the first thermoplastic object 410a and the second thermoplastic object 410b are: Any material that softens at or near skin surface temperature will suffice. Thermoplastic materials are used inside secondary batteries. Since it will be installed, there is a risk of contact with the electrolyte. Select a thermoplastic material that is resistant to the electrolyte. Alternatively, measures must be taken to prevent the thermoplastic object from coming into contact with the electrolyte. It is preferable to cover the thermoplastic object with a film that is resistant to electrolytes and has high thermal conductivity.

[0132] By providing the first thermoplastic object 410a and the second thermoplastic object 410b, the secondary electricity Even when the battery 400 is bent, wrinkles are formed in the film of the outer casing around the outer edge of the secondary battery 400. This allows for a configuration that is less susceptible to such attacks.

[0133] Furthermore, in order to increase the capacity of the secondary battery 400, the positive electrode 101, separator 103, and negative electrode When multiple combinations of 102 layers are stacked and housed in an outer casing, the total thickness becomes thicker. As a result, the difference in thickness between the outer edge and the outer edge becomes large, causing a step in the film of the outer casing. To mitigate this, a first thermoplastic object 410a and a second thermoplastic object 410b It is preferable to provide this.

[0134] Figure 4(A-1) is a cross-sectional view obtained by cutting Figure 4(A) along the dashed line A-A'.

[0135] In cross-section A-A', the negative electrode 102 is slightly wider than the positive electrode 101. Extreme 102 has been made slightly larger, for example, by about 5% in width.

[0136] In cross-section A-A', separator 103 is slightly wider than negative electrode 102. Separator 1 Electrode 03 is slightly larger than the negative electrode 102, and is manufactured to be about 5% wider, for example.

[0137] Figure 4(A-2) is a cross-sectional view of Figure 4(A) taken along the dashed line B-B'. First thermoplastic A positive electrode 101 and a separator 103 are placed between the thermoplastic object 410a and the second thermoplastic object 410b. And install it so that the negative electrode 102 is located.

[0138] The height of the first thermoplastic object 410a and the second thermoplastic object 410b is such that the positive electrode 101 is at the center. It is preferable to form the laminate of the parator 103 and negative electrode 102 to a similar degree. Also, the upper outer casing 1 The bonding area 411 of 07 overlaps with the layered area of ​​the positive electrode 101, separator 103, and negative electrode 102. It is preferable to have a cross-sectional shape that gently smooths out the step in the area that overlaps with the body. Also, the first heat The plastic object 410a and the second thermoplastic object 410b are in contact with the upper outer casing 107. There is a possibility that the exterior will get scratched if it is formed into a smooth curved surface without creating any sharp corners. This can suppress that.

[0139] Figure 4(A-3) shows Figure 4(A) combined with the thermoplastic object 110 described in Embodiment 1. This is a cross-sectional view of an example of the embodiment, cut along the dashed line B-B'. A first thermoplastic object 410a and a second thermoplastic object 410b are provided therein. The positive electrode 101, separator 103, and negative electrode 102 are positioned between them.

[0140] Furthermore, an example using two thermoplastic materials, the first thermoplastic material 410a and the second thermoplastic material 410b, is shown. However, it is not particularly limited and may be used as a single U-shaped thermoplastic object 410. An example is shown in 4(C). Alternatively, a single frame-shaped thermoplastic object may be used.

[0141] This embodiment can be freely combined with other embodiments.

[0142] (Embodiment 3) As one embodiment of this model, a thermoplastic material is provided on the surface of an electronic device equipped with a secondary battery. This demonstrates that one embodiment can be appropriately combined with other embodiments.

[0143] Figure 5 shows an example of a thermoplastic material being applied to the surface of an electronic device equipped with a secondary battery. Figure 5(A Figure 5(B) is a perspective view of the electronic device, and Figure 5(B) is a cross-sectional view.

[0144] The electronic device 500 includes a support 501 having a curved surface and a secondary battery installed inside the support 501. 502 and a display unit 503 provided on the surface of the support 501, the support 501 has two A thermoplastic material 504 is formed on the surface of the inner curved surface with the smaller radius of curvature among the two curved surfaces. ru.

[0145] Electronic device 500 has applications such as watches and bracelets. Electronic device 500 measures body temperature appropriately It would be great if it could be received with sincerity. For example, it could be used as an anklet or collar. ru.

[0146] The support 501 is made of a material that has enough flexibility to be wrapped around the body for use. This is not particularly limited.

[0147] The secondary battery 502 does not necessarily have to have a thermoplastic material as described in Embodiments 1 and 2. Furthermore, it may also contain thermoplastic material.

[0148] The display unit 503 is, for example, an organic EL display formed using a flexible plastic substrate. A spray can be used. The display unit 503 is deformable in accordance with the deformation of the support 501. It is preferable that, for example, in addition to organic EL displays, electrophoretic displays ( Electronic paper is also preferable.

[0149] It is not essential that the thermoplastic object 504 be placed on the outermost surface of the electronic device 500. If body heat is transferred to the body, it may be placed inside the support, or for example, a thermoplastic material. The surface may be covered with a material that has good thermal conductivity.

[0150] This embodiment can be freely combined with other embodiments.

[0151] (Embodiment 4) In this embodiment, the film surface is embossed and a film having a pattern is used. This shows an example of how to manufacture a lithium-ion secondary battery.

[0152] First, a sheet made of a flexible substrate is prepared. The sheet uses a laminate and a metal film. Use a device that has an adhesive layer (also called a heat seal layer) on one or both sides. The bonding layer uses a heat-sealable resin film containing polypropylene or polyethylene. In terms of application form, the sheet has a nylon resin on the surface of aluminum foil. A metal foil with an acid-resistant polypropylene layer and a laminate of polypropylene layers on the back. Use a sheet. Cut this sheet to prepare the film 60 shown in Figure 6(A).

[0153] Then, this film 60 is embossed, and the film surface is as shown in Figure 6(B). This creates a textured surface and forms a visible pattern. Note that after cutting the sheet, The following is an example of embossing, but the order is not particularly limited; embossing should be done before cutting the sheet. The sheet may be processed and then cut to obtain the state shown in Figure 6(B). Alternatively, the sheet may be folded. You can also bend it, heat-seal it, and then cut it.

[0154] The following is an explanation of embossing, a type of press work.

[0155] Figure 7 is a cross-sectional view showing an example of embossing. Embossing is a type of press work. It is a type of embossing roll in which an embossed roll with an uneven surface is pressed onto a film, and the embossed roll Embossing refers to the process of creating irregularities on the film surface that correspond to the irregularities of the surface. A roll is a roll with a pattern engraved on its surface.

[0156] Figure 7(A) shows an example of embossing on one side of a film.

[0157] In Figure 7(A), the embossing roll 53 is in contact with one side of the film, and the other side The film 50 is sandwiched between the roll 54 that is in contact with it, and the film 50 is in the direction of the film's movement. This shows the film being fed out to 58. The film surface is being processed by pressure or heat to create a pattern. It is forming.

[0158] Figure 7(A) shows the embossing roll 53 and roll 54 (metal roll or elastic roll (rubber roll) It is a combination of (e.g., 'ru').

[0159] Figure 7(B) shows an example of embossing applied to both sides of the film.

[0160] In Figure 7(B), the embossing roll 53 is in contact with one side of the film, and the other side The film 51 is sandwiched between the embossing roll 55 that is in contact with the film, and the film 51 is the film This indicates that the train is being sent out in the direction of travel 58.

[0161] Figure 7(B) shows the embossed rolls 53 and 55, which are male pattern embossed rolls. This is a combination of female and female peduncles.

[0162] In addition, embossing raises a portion of the surface of the film 51, and embossing indents the surface. The continuous bumps and ridges form a pattern on the surface of the film 51.

[0163] In Figure 7(C), the embossing roll 56 is in contact with one side of the film, and the other side The film 52 is sandwiched between the embossing roll 57 that is in contact with the film This indicates that the train is being sent out in the direction of travel 58.

[0164] Figure 7(C) shows the embossing roll 56, also known as Tip to Tip, and its embossing This is a combination of roll 56 and embossed roll 57, which have the same pattern. The phases of the convex and concave parts are aligned, resulting in a pattern with almost no difference between the front and back of the film 52. It can be formed.

[0165] Furthermore, the use of embossing rolls is not limited to embossing plates; embossing plates may also be used. Furthermore, it is not limited to embossing; it is possible to create raised relief on a part of the film. Anything that is legal is fine.

[0166] In this embodiment, a pattern is formed by creating bumps and ridges on both sides of the film 60, and the film 61 is placed in the middle. The structure involves folding it in the middle and sealing the three sides of the four sides (excluding the folded side) with an adhesive layer. do.

[0167] Next, fold the film 61 along the dotted line shown in Figure 6(B), resulting in the state shown in Figure 6(C). do.

[0168] A secondary battery having a pattern with irregularities on the surface of the outer casing film 61 is a secondary battery It can relieve the stress applied when bending. It relieves the strain caused by stress. By designing the structure in such a way that the outer casing, etc., does not get damaged when the secondary battery is bent or deformed. Long-term reliability can be ensured without any additional effort.

[0169] This embodiment can be freely combined with other embodiments.

[0170] (Embodiment 5) In this embodiment, an example of manufacturing a secondary battery using a current collector having a meandering section is shown below.

[0171] First, a positive electrode active material layer is formed on one or both sides of a strip-shaped metal foil.

[0172] Next, the positive electrode active material layer is selectively removed by laser irradiation. The area to be removed is later This process creates two areas: a narrow region where the lead electrode is connected, and a narrow section of the meandering part. Yes, and laser processing is performed. This laser processing involves both the positive electrode active material layer and the metal foil. Selectively removes the current collector. Here, the current collector is processed to draw the outline of the current collector having a meandering section. The shape is formed. At this stage, the state shown in Figure 8(A) can be obtained. Figure 8(A) As shown, a part of the current collector (the base of the meandering pattern) is exposed, and the positive electrode active material layer 18a And the positive electrode active material layer 18b is formed.

[0173] Furthermore, although the outer shape of the current collector was formed here by laser processing, a cutting device or hammering device could also be used. After processing the metal foil into the desired shape using a die-cutting machine, further laser processing is performed to create complex shapes. This may also be a process for forming a current collector in a specific shape.

[0174] Furthermore, laser processing is performed after forming an active material layer on one or both sides of the positive electrode current collector 12. This is preferable. The cut surface formed by irradiating with laser light is given strong energy and collects current. This is desirable because it allows the body and the active material layer to adhere firmly.

[0175] As shown in Figure 8(A), there are at least two or more narrow sections in the meandering part of the current collector. Yes, at least one location (the base of the meandering pattern) is the boundary between adjacent active material layers (positive electrode active material This overlaps with the region between the material layer 18a and the positive electrode active material layer 18b.

[0176] Figure 8(B) is a photograph taken with the positive electrode current collector 12 being held with tweezers. As shown in A), the width of the meandering portion of the positive electrode current collector 12 is non-uniform.

[0177] Next, a negative electrode active material layer is formed on one or both sides of another strip-shaped metal foil.

[0178] Next, the negative electrode active material layer is selectively removed by laser irradiation. The area to be removed is later This process creates a narrow area that connects to the lead electrode. Then laser processing is performed. In laser processing, the shape of the current collector is determined by creating an outline of the current collector, which has a meandering section. To accomplish.

[0179] Figure 8(C) shows a schematic diagram of the top view of the negative electrode current collector 14 and the negative electrode active material layer 19, and the negative electrode current collector is pin Figure 8(D) is a photograph taken while the camera was held in place.

[0180] As shown in Figures 8(A) and 8(C), both the positive and negative electrodes have a meandering section in the current collector. However, the width differs in parts. The meandering sections can also be called the bends or turns. Also, A meandering section is a curved pattern shape that includes a straight line pattern. In this specification, current collection is used. A shape in which part of the contour of the upper surface of a body undergoes two or more bends of 90° or more is called a meandering shape. Also, some current collectors have a rectangular wave shape, triangular wave shape, S-shape, etc. as part of the contour of the upper surface shape. It is included in the meandering shape. Note that the bending in a meandering shape does not need to repeat the same pattern. It may also have an irregular bend. Furthermore, it may be cut out to form a meandering section. The part that is cut off is called a slit.

[0181] In a later step, when the positive electrode current collector and the negative electrode current collector are superimposed, the area superimposed on the slit of the negative electrode current collector... In some cases, the positive electrode active material layer is located in the region. For example, in the case of the current collector in Figure 8, the negative electrode current collector is located in the region. Because the lit and the narrow section of the meandering part of the positive electrode current collector overlap, the positive electrode active material layer forms in this area. If present, the negative electrode active material layer will not be present in the region superimposed with the positive electrode active material layer. The absence of a negative electrode active material layer in the region overlapping with the positive electrode active material layer can cause malfunctions during the battery reaction. There is a risk of this happening. Specifically, carrier ions released from the positive electrode active material layer are most likely to enter the slit. The carrier ions concentrate in the negative electrode active material layer in a nearby region, causing them to precipitate on the surface of the negative electrode active material layer. There is a risk of this happening. Therefore, in the case of a positive electrode active material layer without a negative electrode active material layer in the superimposed region, as shown in Figure 8, Removing the positive electrode active material layer in the narrow, meandering section of the positive electrode current collector by laser irradiation. This allows for the suppression of carrier ion precipitation.

[0182] Furthermore, for the reasons mentioned above, the widths of the slits on the positive and negative electrodes are either equal or greater than the width of the slit on the positive electrode. A larger size is preferable. By increasing the width of the positive electrode slit, the negative area in the overlapping region can be increased. The positive electrode active material layer, which lacks an electrode active material layer, can be eliminated or reduced. Therefore, the negative electrode This can suppress the deposition of carrier ions on the surface of the active material.

[0183] Next, as shown in Figure 9(A), the positive electrode current collector 12 is sandwiched between separators 13. Then the separator A portion 13a of the area of ​​the electrode 13 that does not overlap with the positive electrode current collector 12 is bonded, and the separator 13 Figure 9(B) shows the fabrication of the enclosed positive electrode current collector 12. Note that the separator 13 is made of polypropylene or When using polyvinylidene fluoride (PVDF), heat welding should be performed at a temperature between 190°C and 230°C. This allows them to be bonded together.

[0184] Next, as shown in Figure 9(C), the positive electrode current collector 12 encased in the separator 13 and the negative electrode current collector The bodies 14 are stacked. At this time, multiple positive electrode current collectors 12 and negative electrode current collectors 14 are stacked. This is preferable. In that case, the positive electrode current collector 12 and the negative electrode current collector 14, which are enclosed in the separator 13, They are stacked alternately, and the electrode tab portions of the positive electrode current collector 12 overlap each other, and the negative electrode current collector 14 It is best to have the electrode tab portions overlap each other. Multiple positive electrode current collectors 12 and negative electrode current collectors 14 By stacking and electrically connecting them, the capacity of secondary batteries can be increased.

[0185] Then the stacked separator 13, positive electrode current collector 12, and negative electrode current collector 14 are bundled together and fixed in place. It is preferable to fix it. Fixing is done by adhesive tape, or by using a polyimide film coated with adhesive. This can be done using damp resin tape or similar material.

[0186] Next, the electrode tab portion of the positive electrode current collector 12 is electrically connected to one lead electrode. The electrode tab portion of the current collector 14 is electrically connected to the other lead electrode. The electrical connection is This can be done by ultrasonic welding. Also, multiple positive electrode current collectors 12 and negative electrode current collectors 14 When stacked, the electrode tab portions of one lead electrode and multiple positive electrode current collectors 12 are connected. The process involves ultrasonic welding, and the electrode tab portions of another lead electrode and multiple negative electrode current collectors 14. The process of ultrasonic welding can be carried out simultaneously. This allows for the simultaneous processing of multiple positive electrode current collectors 12 Electrical conductivity is achieved between the negative electrode current collectors 14 and between the multiple negative electrode current collectors 14.

[0187] The lead electrodes connected to the positive electrode current collector 12 should be made of aluminum or a similar material. Any material that can do this should be used. Also, the lead electrodes connected to the negative electrode current collector 14 should be made of copper or similar material. Any material suitable for use as a current collector may be used. It is electrically connected to the positive electrode current collector 12. The lead electrodes are at the same potential as the positive electrode current collector 12, and the same applies to the negative electrode, so the current collector The materials that can be used are those that can be used for lead electrodes.

[0188] Next, as shown in Figures 10(A) and (B), the edges of the film 11 are heat-pressed, leaving two sides untouched. The film is sealed by folding the film. As shown in Figure 10(B), in this embodiment, one side of the film 11 is folded. Since this is the bent side, sealing in this process only needs to be done on one side 11b. This allows the film 1 Within the area enclosed by 1, the stacked separator 13, positive electrode current collector 12, and negative electrode current collector It can hold 14.

[0189] The film 11 may be embossed beforehand. This allows for the creation of more flexible secondary batteries.

[0190] Next, as shown in Figure 10(C), the positive electrode current collector 12 and the sectometer are placed in the area enclosed by the film 11. The film 11 contains the parator 13 and the negative electrode current collector 14, and one side 11c of the film 11 is sealed by heat compression. Stop. At this time, lead electrodes 16a and 16b are in the area surrounded by film 11. Pull it out of the area.

[0191] Next, as shown in Figure 10(D), the electrolyte 20 is injected into the area enclosed by the film 11. Then, while vacuuming, heating, and pressurizing, the film is processed as shown in Figure 10(E). The remaining side 11d of 11 is sealed. These operations can be performed using a glove box, etc. The process is carried out in an oxygen-free environment. Vacuuming is performed using a degassing sealer, liquid sealing sealer, etc. It is good to do so. Also, by sandwiching the film 11 between the two heatable bars of the sealer, It can be sealed by heating and pressurizing. Each condition is, for example, a vacuum level of 6 The pressure can be set to 0 kPa, heating to 190°C, and pressurization to 0.1 MPa for 3 seconds.

[0192] Next, it is preferable to perform an aging treatment on the secondary battery obtained in the above process. The coating process controls the film that forms at the interface between the electrode and the electrolyte, thereby activating the active material. can.

[0193] Furthermore, the aging treatment of the secondary battery was opened once, and the gas generated during the aging treatment was removed. You can remove the gas, add more electrolyte, and reseal it. If present, it can cause an imbalance in the battery reaction and lead to degradation, so the gas must be released and the battery resealed. This can suppress deterioration.

[0194] In this embodiment, the rectangular separator 13, the positive electrode current collector 12, the negative electrode current collector 14 and Since the explanation used film 11, the method of sealing the three sides in order was described, but one of the present inventions The form is not limited to this. When manufacturing secondary batteries other than rectangular ones, the sealing order and method should be adjusted as appropriate. It can be changed.

[0195] A current collector having a meandering pattern, and the positive electrode active material layer at the base of the meandering pattern By selectively removing certain components, a flexible battery can be realized.

[0196] This embodiment can be freely combined with other embodiments.

[0197] (Embodiment 6) Figure 11(A) is a schematic diagram of a device for charging the electronic device 500 described in Embodiment 3. For example, in situations where it is necessary to rapidly charge a secondary battery, the secondary battery may be exposed to heat near body temperature. In cases where it is held, the secondary battery may exceed its limits due to a large, unintended external force. This could lead to a problem where the curve becomes too small when bent upwards. This problem can be resolved by providing a support base 1100.

[0198] The support base 1100 has an upper surface with an appropriate radius of curvature. For example, a radius of curvature of 10 mm or more. It has an upper surface that is [this].

[0199] The support base 1100 maintains a temperature near body temperature on its surface during charging, thereby providing support. The structure may be such that electronic devices are in close contact with the surface of the base 1100. Also, heat near body temperature Once the electronic devices are in close contact, the heat retention process may be discontinued.

[0200] Figure 11(B) is another schematic diagram of a device for charging electronic devices equipped with a secondary battery. Support base The 1100 has a space accessible from the top to the interior where electronic equipment can be housed.

[0201] A material with high thermal conductivity should be placed in areas where thermoplastic objects and chargers come into contact or are in close proximity. It is also possible to design the battery in a way that makes it easier to release heat to the outside.

[0202] When charging a secondary battery, it is not necessary to rapidly charge the battery, or the secondary battery is near body temperature. If there is no heat generated, it is not necessary to provide a support stand like the one in this embodiment.

[0203] This embodiment can be freely combined with other embodiments.

[0204] (Embodiment 7) The electronic device has an antenna for wireless charging and performs wireless charging according to the Qi standard. It is possible to do so. Also, electronic devices use wireless communication to send data used for display to external devices. It has a communication device.

[0205] Electronic devices have power control circuits that control the charging and discharging of secondary batteries.

[0206] Furthermore, other examples of electronic devices are shown in Figure 12.

[0207] As an electronic device that applies a power storage device with a flexible shape, for example, a head mount Head-mounted display devices such as head displays and goggle-type displays, arm-mounted display devices Desktop type, stationary display device (also called television or television receiver) personal computers such as laptops, monitors for computers, and digital cameras. Digital video cameras, digital photo frames, electronic organizers, e-readers, electronic translators Audio input devices such as machines, toys, microphones, electric shavers, electric toothbrushes, and microwave ovens. High-frequency heating devices such as electric rice cookers, electric washing machines, electric vacuum cleaners, water heaters, electric fans, and hair dryers. Air conditioning equipment such as humidifiers, dehumidifiers, and air conditioners, dishwashers, dish dryers, Clothes dryer, futon dryer, electric refrigerator, electric freezer, electric refrigerator-freezer, freezer for DNA preservation. Storage, flashlights, power tools, smoke detectors, alarm systems such as gas alarms and security alarms, industrial Robots, hearing aids, cardiac pacemakers, X-ray machines, radiation detectors, electric massagers Health equipment and medical devices such as dialysis machines, mobile phones (also called mobile phones or mobile phone devices), Portable game consoles, personal digital assistants, lighting devices, headphones, stereos, remote controls Clocks such as desk clocks and wall clocks, cordless phone handsets, transceivers, pedometers, calculators portable or stationary audio playback devices such as digital audio players, pachinko machines, etc. Examples include large game consoles.

[0208] Furthermore, energy storage devices with flexible shapes can be installed in the interior or exterior walls of houses and buildings, or in automobiles. It can also be incorporated along the curved surfaces of the interior or exterior.

[0209] Figure 12(A) shows an example of a mobile phone. Mobile phone 7400 has a housing 7401 In addition to the display unit 7402 incorporated into it, there are operation buttons 7403, an external connection port 7404, and It is equipped with a speaker 7405, a microphone 7406, etc. The mobile phone 7400 also has a battery storage function. It has device 7407.

[0210] Figure 12(B) shows the mobile phone 7400 in a curved state. Mobile phone 740 When the 0 is deformed by an external force and the whole thing is curved, the energy storage device located inside is revealed. The 7407 is also bent. Figure 12(C) shows the state of the bent energy storage device 7407 at that time. The power storage device 7407 is a laminated secondary battery (layered structure battery, film outer casing). It is also called a battery. The energy storage device 7407 is fixed in a bent position. The energy storage device 7407 has lead electrodes 7408 that are electrically connected to the current collector 7409. Yes. For example, the film on the exterior of the energy storage device 7407 is embossed, and Device 7407 has a highly reliable configuration even when bent. Furthermore, mobile phones The 7400 has a slot for inserting a SIM card and USB devices such as USB memory sticks. A connector section for connecting parts may be provided.

[0211] Figure 12(D) shows an example of a bendable mobile phone. Figure 12(E) shows the state of the power storage device 7104. The mobile phone 7100 has a housing 710 1. It comprises a display unit 7102, an operation button 7103, and a power storage device 7104. The device 7104 has a lead electrode 7105 that is electrically connected to the current collector 7106. For example, press processing to form multiple bumps and ridges on the surface of the film of the outer casing of the energy storage device 7104. This ensures high reliability even when the energy storage device 7104 is bent many times with a change in curvature. It is configured to maintain its functionality. Furthermore, the 7100 mobile phone has a SIM card that can be inserted. It includes slots for connecting USB devices such as USB memory sticks, and connectors for connecting USB devices. That's fine.

[0212] Furthermore, if a flexible energy storage device is installed in a vehicle, hybrid electric vehicles (HEVs) and electric vehicles can be used. Next-generation clean energy vehicles such as electric vehicles (EVs) or plug-in hybrid vehicles (PHEVs) This will enable the creation of energy-efficient vehicles, as well as motorized bicycles including agricultural machinery and electric-assist bicycles. Motorcycles, electric wheelchairs, electric carts, small or large vessels, submarines, fixed-wing aircraft and rotary-wing aircraft. Curved bodies such as aircraft, rockets, satellites, space probes, planetary probes, and spacecraft. It can also be equipped with a power storage device that can provide energy.

[0213] Figure 13 illustrates a vehicle using one aspect of the present invention. Figure 13(A) shows automobile 8 The 100 is an electric vehicle that uses an electric motor as its power source for driving. Alternatively, The vehicle can appropriately select and use an electric motor and an engine as power sources for propulsion. It is a hybrid vehicle. When a laminated secondary battery is installed in the vehicle, multiple laminates A battery module integrating a nate structure rechargeable battery is installed in one or more locations. To do so, by using one aspect of the present invention, the energy storage device itself can be made smaller and lighter, for example For example, by installing a curved energy storage device on the inside of the tire, it is possible to realize a vehicle with a long driving range. Yes, it is possible. Furthermore, power storage devices of various shapes can be placed in the gaps of the vehicle, including the trunk. This allows for the securing of space and passenger space inside the vehicle. Furthermore, the vehicle 8100 has an energy storage device. The energy storage device not only drives the electric motor 8106, but also the headlights 8101 and It can supply power to light-emitting devices such as home lights (not shown).

[0214] Furthermore, the energy storage device is used for the speedometer, tachometer, and other displays of the 8100 automobile. It can supply power to the device. In addition, the energy storage device is the navigation system of the automobile 8100. It can supply power to semiconductor devices such as junction gate systems.

[0215] The automobile 8200 shown in Figure 13(B) is plugged into the energy storage device of the automobile 8200. It can be charged by receiving power from an external charging facility using methods such as contactless power supply. Figure 13(B) shows the power supply from the ground-mounted charging device 8021 to the vehicle 8200. This shows the state in which the power device is being charged via cable 8022. The electrical method and connector standards will be as appropriate, using the prescribed methods such as CHAdeMO® or Combo. It is fine to do so. The charging device 8021 may be a charging station installed in a commercial facility, It may also be a household power supply. For example, a plug-in system can be used to supply power from an external source. The energy storage device 8024 installed in the automobile 8200 can be charged. Charging is performed by A This can be done by converting AC power to DC power via a conversion device such as a CDC converter. ru.

[0216] Although not shown in the diagram, a power receiving device is mounted on the vehicle, and power is supplied wirelessly from a ground-based power transmission device. It can also be charged by doing so. In this contactless power supply method, power transmission equipment is installed in roads or exterior walls. By incorporating this, charging can be performed not only when the vehicle is stopped but also while it is in motion. Furthermore, this contactless power supply... This method can be used to transmit and receive power between two vehicles. Furthermore, outside the vehicle Solar cells may be installed in the equipment to charge the energy storage device when the vehicle is stopped or in motion. For power supply via contact, electromagnetic induction or magnetic resonance methods can be used.

[0217] According to one aspect of the present invention, the degree of freedom in the installation location of the energy storage device is increased, and the vehicle design of the car becomes more efficient. This can be done. Furthermore, according to one aspect of the present invention, the energy storage device itself can be made smaller and lighter. This can be achieved. If the energy storage device itself can be made smaller and lighter, it will contribute to reducing the weight of the vehicle, thus increasing the driving range. This can improve separation. Also, the power storage device mounted on the vehicle can be used as a power source other than the vehicle. It can also be used in this way. In this case, it avoids using commercial power during peak electricity demand. It is possible.

[0218] This embodiment can be freely combined with other embodiments.

[0219] Furthermore, the content described in one embodiment (even a part of it) may vary depending on the form of its implementation. Other content (even partial content) described in the tone, and / or one or more other implementations To apply, combine, or replace the content described in the form (even if only a part of it is acceptable), It is possible to do things like this.

[0220] Furthermore, the content described in each embodiment refers to the use of various figures in each embodiment. This refers to the content stated, or the content stated using the text described in the specification.

[0221] Furthermore, in one embodiment, the diagram (even if only a part of it) described may refer to another part of that diagram. Further figures (even partial ones) described in that embodiment, and / or one or more figures. In another embodiment, the diagram (or even just a part of it) described above can be combined by This allows for the creation of even more diagrams. [Explanation of symbols]

[0222] 11 Film 11b One side 11c (one side) 11d side 12 Positive electrode current collector 13 Separator 13a Part of the region that does not overlap with the positive electrode current collector 12 14 Negative electrode current collector 16a Lead electrode 16b Lead electrode 18a Cathode active material layer 18b Positive electrode active material layer 19 Negative electrode active material layer 20 Electrolyte 50 film 51 film 52 film 53 Embossing Roll 54 rolls 55 Embossing Roll 56 Embossing Roll 57 Embossing Roll 58 Direction of travel 60 film 61 film 100 Secondary battery 101 Positive electrode 101a positive electrode 101b Positive electrode 102 Negative electrode 102a negative electrode 102b negative electrode 103 Separator 104 Positive lead 105 Negative lead 107 Exterior 110 Thermoplastic objects 110a First thermoplastic object 110b Second thermoplastic material 331 First Domain 332 Second Domain 333 The Third Domain 400 Secondary battery 410a First thermoplastic material 410b Second thermoplastic material 411 Adhesive area 500 Electronic equipment 501 Support 502 Secondary battery 503 Display section 504 Thermoplastic objects 1100 Support stand 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 Contents 7100 Mobile Phone 7101 enclosure 7102 Display section 7103 Operation Buttons 7104 Energy storage device 7105 Lead Electrode 7106 Current collector 7400 mobile phones 7401 enclosure 7402 Display section 7403 Operation Buttons 7404 External connection port 7405 Speaker 7406 Microphone 7407 Energy storage device 7408 Lead Electrode 7409 Current collector 8021 Charging device 8022 Cable 8024 Energy storage device 8100 Automobile 8101 Headlight 8106 Electric motor 8200 automobiles

Claims

1. A lithium-ion secondary battery having a positive electrode, a negative electrode, and an electrolyte, The positive electrode comprises a positive electrode current collector and a positive electrode active material layer located on one or both sides of the positive electrode current collector. In a plan view, The positive electrode current collector has an L-shaped portion, The L-shaped portion has a first side and a second side located on the inside, and a portion located between the first side and the second side having an angle of approximately 270 degrees. A lithium-ion secondary battery in which, in the portion having an angle of approximately 270 degrees, the outer edge of the positive electrode current collector has a shape that is recessed toward the inside of the positive electrode current collector.

2. A lithium-ion secondary battery having a positive electrode, a negative electrode, and an electrolyte, The negative electrode comprises a negative electrode current collector and a negative electrode active material layer located on one or both sides of the negative electrode current collector. In a plan view, The negative electrode current collector has an L-shaped portion, The L-shaped portion has a first side and a second side located on the inside, and a portion located between the first side and the second side having an angle of approximately 270 degrees. A lithium-ion secondary battery in which, in the portion having an angle of approximately 270 degrees, the outer edge of the negative electrode current collector has a shape that is recessed toward the inside of the negative electrode current collector.

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