Secondary battery

Abstract

To provide a secondary battery suitable for a portable information terminal or a wearable device; or , electronic devices of novel structures having various external shapes, and secondary electrodes of shapes suitable for the shapes To provide a secondary battery, or a secondary battery that has been damaged by an unexpected large external force. The problem of electronic devices being bent beyond their limits, resulting in a radius of curvature that is too small, It can be resolved. A secondary battery has a structure in which a separator is sandwiched between a positive electrode and a negative electrode. The temperature between this structure and the exterior body must be within the range of human skin surface temperature (30°C to 37°C). This provides a soft thermoplastic material.

Description

[Technical field]

[0001] One aspect of the present invention relates to a secondary battery. The present invention also relates to a process, a machine, a manufacture, or a composition ( Another aspect of the present invention relates to a semiconductor device, a surface Display device, light emitting device, imaging device, power storage device, driving method thereof, or manufacturing method thereof In particular, it relates to electronic devices.

[0002] In this specification, the term "electronic device" refers to any device having a secondary battery. Electro-optical devices having a secondary battery, information terminal devices having a secondary battery, vehicles having a secondary battery, etc. It is an electronic device. [Background technology]

[0003] In recent years, mobile information terminals, such as smartphones, have been actively developed. There is a strong demand for portable information terminals, which are a type of electronic device, to be lightweight and compact.

[0004] You can get information visually anywhere without having to worry about where you are and without restricting the freedom of your hands. As an example of a wearable device, Patent Document 1 is disclosed. The device disclosed in Patent Document 1 is a goggle-type display device that can receive and transmit signals and includes a CPU. Chairs are also included as a type of electronic device.

[0005] Wearable devices and mobile information terminals are equipped with secondary batteries that can be repeatedly charged and discharged. Wearable devices and mobile information terminals are often mounted on the body, and because of their light weight and small size, The capacity of the batteries installed in these devices is limited, making it difficult to operate wearable devices and mobile information terminals. The problem is that the operation time is limited. Secondary batteries are required to be lightweight, small, and capable of long-term use. There are.

[0006] Examples of secondary batteries include nickel-metal hydride batteries and lithium-ion secondary batteries. However, lithium-ion secondary batteries are being actively developed because they have high capacity and can be made small. It is believed that.

[0007] In a lithium ion secondary battery, the electrodes that function as the positive electrode or the negative electrode are Materials used include silicon metals, carbon-based materials, and alloy-based materials. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2005-157317 A Summary of the Invention [Problem to be solved by the invention]

[0009] One of the objectives of the present invention is to provide a secondary battery suitable for a portable information terminal or a wearable device. Another object of the present invention is to provide a novel power storage device.

[0010] Or, to provide an electronic device with a new structure. Specifically, to provide various external shapes. To provide an electronic device having a novel structure capable of performing various external shapes. It is also an object of the present invention to provide an electronic device having such a structure and a secondary battery having a shape suitable for the electronic device. .

[0011] A secondary battery or an electronic device with a secondary battery placed inside it may be damaged by an unexpected large external force. The task was to solve the problem of devices being bent beyond their limits, resulting in a radius of curvature that is too small. This is one of the topics.

[0012] The description of these problems does not preclude the existence of other problems. The embodiment does not necessarily have to solve all of these problems. The above will become apparent from the description in the specification, drawings, claims, etc. It is possible to extract other issues from the descriptions in the patent, claims, etc.

[0013] Electronic devices such as mobile information terminals and wearable devices require miniaturization and complex external shapes. In addition, these electronic devices require secondary batteries. When making the device smaller or with a complex external shape, it is necessary to install a secondary battery in the electronic device. This results in a situation where the volume of the internal space becomes smaller and the shape becomes complex.

[0014] The secondary batteries generally used in mobile information terminals are rectangular batteries protected by metal cans or hard resin. It has a body shape.

[0015] The rectangular secondary battery itself is not flexible, so it is difficult to install it in electronic devices with complex external shapes. If the internal space has a curved surface, the internal space of a rectangular secondary battery can be used efficiently. There is a limit to what can be done.

[0016] Therefore, it is becoming possible to use a secondary battery that is flexible and can change its shape in electronic devices. This makes it possible to efficiently arrange secondary batteries in the internal space of electronic equipment having a complex external shape. can.

[0017] There are several ways to interpret the meaning of making electronic devices have complex external shapes. The exterior of the device is given a complex shape, for example a curved shape, and then fixed in place. In this case, the secondary battery must be bent once and then fixed in the bent state. There are two types of electronic devices: those that do not deform when force is applied from the outside, and those that do deform when force is applied. In addition, there are also electronic devices with simple external shapes that can be used to protect against external forces. When applying force to an electronic device, the deformation is It is desirable that the secondary battery can also be deformed into a complex external shape each time stress is applied.

[0018] In addition, wearable devices include wearable cameras, wearable microphones, Wearable input devices such as wearable sensors, wearable displays, and wearable Wearable output devices such as speakers and wearable input devices that combine these functions Also, wearable devices include devices that control each device, calculate data, or This includes a device that performs processing, typically a wearable computer with a CPU. A wearable device is a device that stores, transmits, and receives data. This also includes portable information terminals and memory.

[0019] The exterior is made of a laminate of metal foil (aluminum, stainless steel, etc.) and resin (thermal adhesive resin). When a film containing ZnO (also called a laminate film) is used, it is possible to reduce the amount of ZnO in the battery compared to secondary batteries that use metal cans. It is also lightweight, making it possible to fabricate a thin secondary battery.

[0020] In secondary batteries using laminate films, the positive electrode, separator, and negative electrode are laminated alternately. This laminated structure is made up of the commonly known sheet-shaped positive electrode, separator, and negative electrode. This has the advantage that it is easier to dissipate heat than secondary batteries with a wound electrode structure.

[0021] In addition, the laminate film is flexible, and the positive and negative electrodes are made of thin metals. The current collector and separator are made of thin resin, so this secondary battery cannot be exposed to external When force is applied, it can deform into a complex external shape.

[0022] As an example of how the secondary battery can be modified to have a complex external shape, it can be made to have a curved surface. This allows the secondary battery to be efficiently arranged in the internal space of an electronic device having a complex external shape. In addition, the electronic device can be operated in a complicated manner with the secondary battery disposed in the internal space of the electronic device. It can be transformed into various external shapes.

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

[0024] If it is bent beyond its limit, the laminate film will break and the secondary battery will not be able to return to its original shape. In addition, when the positive or negative electrode breaks and is cut, the sharp cut surface pierces the separator. This can cause problems such as the secondary battery breaking and shorting internally, making it unusable. If the radius of curvature becomes too small, the stress on the components of the secondary battery will increase, causing the current collector to Problems such as peeling off of the active material may occur. [Means for solving the problem]

[0025] As electronic devices with complex external shapes, bendable wristwatches and bracelets that can be used to change the shape of the device Consider a product that is circular or has a missing part.

[0026] Watches and bracelets are worn around the body. Therefore, placing secondary batteries inside electronic devices In this case, a secondary battery that can be bent so as to be wrapped around a human arm is preferable.

[0027] In addition, in order to remove a watch or bracelet from the body, the electronic device must be unbent. When placing a secondary battery in the internal space of an electronic device, it is necessary to be careful not to loosen it from a bent state. Secondary batteries are preferred.

[0028] When wearing a watch or bracelet around your body, make sure your wrist or arm is not inside the watch or bracelet. Therefore, if the radius of curvature becomes too small beyond the limit explained above, However, when the watch or bracelet is not being worn, it may cause unintended external Large force from the inside of the electronic device may be applied to the secondary battery placed inside the electronic device. There is a risk of problems occurring.

[0029] Problems may occur with secondary batteries placed inside electronic equipment due to unintended external forces. As a measure to prevent this problem, the laminate film, positive electrode, There is a method to protect the separator and negative electrode with a material that is less likely to deform under force. do.

[0030] However, the above method also makes the secondary battery difficult to bend, and It is not advisable to bend the secondary battery when inserting it into a socket or when removing it from the socket. stomach.

[0031] Inside the secondary battery, a separator is sandwiched between the positive and negative electrodes. Between the device and the body, the temperature is approximately the same as the surface temperature of human skin (30°C to 37°C). Thermoplastic objects that become softer than they are at about 25° C., such as glass, in the above temperature range. A thermoplastic resin having a transition temperature is provided.

[0032] When wearing a watch or bracelet on the body, the thermoplastic material inside the secondary battery comes into contact with the surface of the human skin. This causes the cable to absorb heat and become soft, making it difficult to bend when wrapping it around the cable. Since thermoplastic objects are soft, they cannot withstand large unintended external forces. The property of protecting against bending beyond the limit and the problem of the radius of curvature becoming too small However, these problems do not occur when the device is worn because the wrist, arm, etc. are present.

[0033] When a watch or bracelet is removed from the body, the thermoplastic material inside the secondary battery absorbs heat from the surface of the human skin. When the watch or bracelet is not being worn, it may become unintentional. The problem of bending beyond the limit due to a large external force or the radius of curvature becoming too small is not solved. The probability of this occurring is higher than when the thermoplastic object is in a hard state. The battery's protective properties are restored.

[0034] Thermoplastic with a glass transition point in the range close to the skin surface temperature (30°C to 37°C) As an example of the thermoplastic resin, for example, polyvinyl acetate (glass transition temperature T g is about 31°C). Polyvinyl acetate becomes soft when heated to about 31°C. Regardless of whether it has a thermal barrier or not, as long as the object becomes soft at near the skin surface temperature, the material is not limited. It won't be done.

[0035] The thermoplastic body is not limited to homopolymers, but may also be copolymers.

[0036] Thermoplastic objects can be objects whose glass transition point is adjusted by mixing plasticizers into them. That's fine.

[0037] Since the thermoplastic object is provided inside the secondary battery, there is a risk that it may come into contact with the electrolyte. Select a resistant thermoplastic or ensure that the thermoplastic does not come into contact with the electrolyte. For example, a thermoplastic material that is resistant to the electrolyte and has high thermal conductivity must be used. It is advisable to cover the

[0038] The thermoplastic material is placed between the positive and negative electrodes and the separator, and the exterior. Position the thermoplastic object close to the human skin surface to efficiently transfer heat. It is possible to place them in multiple locations, but in that case, they should be placed so that heat is transferred to them at the same time and to the same extent. It is preferable to do so.

[0039] In addition, the location of the thermoplastic object is not limited to the inside of the secondary battery. For example, Thermoplastic objects may be placed on the outside of the electronic device in which they are placed. Thermoplastic objects may not come into direct contact with the surface of human skin. It may be a structure in which the other material is sandwiched between the two. In that case, the other material is Materials with high thermal conductivity are preferred.

[0040] One embodiment of the configuration of the invention disclosed in this specification has a radius of curvature of 30 mm, preferably a radius of curvature of 10 mm. The secondary battery can be deformed to a shape with a curved surface of curvature m. After being deformed into a shape with a curved surface of radius 30 mm, it is transformed into a shape with a curved surface of radius 150 mm. Variations are also possible.

[0041] The radius of curvature of a surface will be described with reference to FIG. 14. In FIG. 14(A), a curved surface 1700 A part of a curve 1702 included in the surface 1700 is cut into a plane 1701 by an arc of a circle. The radius of the circle is taken as the radius of curvature 1703, and the center of the circle is taken as the center of curvature 1704. FIG. 14B shows a top view of the curved surface 1700. FIG. 14C shows the curved surface 1 When cutting a curved surface with a plane, the angle of the plane to the curved surface and The radius of curvature of the curve that appears in the cross section varies depending on the cutting position. Now, the smallest radius of curvature is taken as the radius of curvature of the surface.

[0042] A secondary battery consisting of two sheets of film as the exterior body, sandwiching the contents 1805 including electrodes and electrolyte. When the secondary battery is bent, the curvature of the film 1801 on the side closer to the curvature center 1800 of the secondary battery The radius 1802 is larger than the radius of curvature 1804 of the film 1803 on the far side from the center of curvature 1800. In this case, the value of the radius of curvature close to the center of curvature is used as the quadratic function. This is the radius of curvature of the battery.

[0043] The cross-sectional shape of the secondary battery is not limited to a simple arc shape, and may be a shape that includes a partial arc. For example, the shape shown in FIG. 15(B), a wavy shape (FIG. 15(C)), an S-shape, etc. In the case where the curved surface of the secondary battery has a shape having a plurality of centers of curvature, Among the radii of curvature at the centers of curvature of the two surfaces, the surface with the smallest radius of curvature is The radius of curvature of the outer casing closer to the center of curvature of the outer casing may be changed up to 30 mm, preferably up to 10 mm. It can be shaped.

[0044] The film used for the exterior of secondary batteries is a metal film (aluminum, stainless steel, nickel, etc.). Steel, gold, silver, copper, titanium, nichrome, iron, tin, tantalum, niobium, molybdenum, zirconium Metals or alloys that can be used as metal foils, such as aluminum or zinc, and plastic foils made of organic materials Hybrids 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 selected from the following or a laminated film made up of multiple of these is used. Metal The film is easy to emboss and can be embossed to form recesses or protrusions. This increases the surface area of ​​the film exposed to the outside air, providing excellent heat dissipation properties.

[0045] The sealing structure of the secondary battery is a rectangular film folded in the center. The structure has three of the four sides, excluding the bent part, fixed with an adhesive layer to close the structure, and two sheets The film is layered and the four sides of the film are fixed with an adhesive layer to seal the film.

[0046] The adhesive layer can be a thermoplastic film material, a heat-curing adhesive, or an anaerobic adhesive, a UV-curing adhesive, The adhesive may be a photocurable adhesive or a reactive curable adhesive. Materials used include epoxy resin, acrylic resin, silicone resin, and phenolic resin. There can be. Effect of the Invention

[0047] It is possible to provide a secondary battery suitable for a portable information terminal or a wearable device. It is possible to provide a power storage device.

[0048] Alternatively, electronic devices with novel structures can be provided. It is possible to provide electronic devices having a novel structure that can be used in various external shapes. It is possible to provide an electronic device having a large structure and a secondary battery having a shape suitable for the shape of the electronic device.

[0049] The secondary battery or the electronic device in which the secondary battery is placed may be damaged by an unexpected large external force. This eliminates the problem of devices being bent beyond their limits, resulting in a radius of curvature that is too small.

[0050] Since the shape of the secondary battery can be freely designed, for example, by using a secondary battery having a curved surface, This increases the degree of freedom for electronic devices as a whole, making it possible to realize electronic devices with a variety of designs. In addition, the surface of the electronic device can be easily adjusted without creating unnecessary space in the gaps inside the electronic device. By providing a secondary battery inside the curved surface of the electronic device along the curved surface, it is possible to utilize space inside the electronic device. For example, the electronic device can be used with a flexible display unit having a certain area. In the case where the display unit has a display area, a gap having a certain area is formed on the rear side of the display unit. The secondary battery can effectively utilize gaps with a certain amount of area, and by making effective use of the area, This makes it possible to make a thin secondary battery.

[0051] Therefore, electronic devices with novel structures can be realized.

[0052] The description of these effects does not preclude the existence of other effects. An embodiment does not necessarily have to have all of these effects. Effects other than these may also be included. The above is self-evident from the description, drawings, claims, etc. Other effects can be extracted from the claims and other descriptions. [Brief description of the drawings]

[0053] [Figure 1] 1A and 1B are a top view illustrating one embodiment of the present invention and a schematic diagram illustrating a current flow during charging of a secondary battery. [Diagram 2] 1A and 1B are a perspective view and a cross-sectional view illustrating one embodiment of the present invention. [Diagram 3] FIG. 1 is a diagram of a particle illustrating one embodiment of the present invention. [Figure 4] 1A and 1B are a top view and a cross-sectional view illustrating one embodiment of the present invention. [Diagram 5] 1A and 1B are a perspective view and a cross-sectional view illustrating one embodiment of the present invention. [Figure 6] FIG. 1 is a top view illustrating one embodiment of the present invention. [Figure 7] FIG. 2 is an explanatory diagram of an embossing process according to one embodiment of the present invention. [Figure 8] 1A and 1B are a top view and a photograph illustrating one embodiment of the present invention. [Figure 9] 1A and 1B are a top view and a perspective view illustrating one embodiment of the present invention. [Figure 10] FIG. 1 is a perspective view illustrating one embodiment of the present invention. [Figure 11] FIG. 1 is a diagram showing an appliance for charging an electronic device according to one embodiment of the present invention. [Figure 12] 1A to 1C are diagrams illustrating an electronic device including a flexible power storage device and a power storage device, illustrating one embodiment of the present invention. [Figure 13] FIG. 1 illustrates a vehicle including a secondary battery according to one embodiment of the present invention. [Figure 14] FIG. 13 is a diagram illustrating the radius of curvature of a surface. [Figure 15] FIG. 13 is a diagram illustrating the radius of curvature of a surface. [Figure 16] FIG. 1 is a perspective view illustrating one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0054] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following description, and various modifications in form and details are possible by those skilled in the art. The present invention is not limited to the description of the following embodiments. It is not something that can be done.

[0055] "Electrically connected" means connected via "something that has some kind of electrical effect." Here, "something that has some electrical effect" means an electrical signal between connected objects. There are no particular restrictions as long as it allows the exchange of numbers.

[0056] The position, size, range, etc. of each component shown in the drawings are not necessarily the actual size for ease of understanding. Therefore, the disclosed invention may not necessarily represent the position, size, range, etc. Furthermore, the present invention is not limited to the position, size, range, etc. disclosed in the drawings, etc.

[0057] Ordinal numbers such as "first," "second," and "third" are used to avoid confusion of components. It is.

[0058] In this specification, "parallel" means that two straight lines are arranged at an angle of -10° or more and 10° or less. Therefore, it includes the case where the angle is between -5° and 5°. refers to the state in which two straight lines are arranged at an angle between 80° and 100°. This 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 a positive electrode and a negative electrode. Between the exterior body and the heat exchanger, the temperature is approximately the same as the human skin surface temperature (30°C to 37°C). An example of manufacturing a secondary battery provided with a thermoplastic object that becomes softer than in the initial state will be described.

[0060] FIG. 1(A) shows an example of a schematic diagram of a secondary battery. Also, the internal structure surrounded by the exterior body of the secondary battery is shown. An example of the structure is shown in FIG.

[0061] The secondary battery 100 according to one embodiment of the present invention includes a positive electrode 101 and a separator 10 inside an exterior body 107. The secondary battery has at least a cathode 102, a thermoplastic body 110, and an electrolyte. There are various structures for the structure, but in this embodiment, a film is used to form the exterior body 107. Use.

[0062] The film for forming the exterior body 107 is a metal film (aluminum, stainless steel, nickel, etc.). Nickel steel, gold, silver, copper, titanium, nichrome, iron, tin, tantalum, niobium, molybdenum, Metals or alloys that can be used as metal foils, such as zinc or vanadium, plastic foils made of organic materials, Hybrids 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 selected from the following, or a laminate film made up of a plurality of these, is used.

[0063] In this embodiment, the thermoplastic object 110 is a thermoplastic material that covers the surface of the positive electrode 101 having the largest area. However, the thermoplastic body 110 and the positive electrode 101 are in the form of a sheet. The relationship of the larger surface is not limited to this. For example, the relationship of the areas of the two may be reversed. Furthermore, the two may be in a partially overlapping relationship. The object 110 is thicker than the separator 103. The thermoplastic object 110 is The thermoplastic object 110 is not limited to a rectangle, but may have four corners. The shape of the thermoplastic object 110 may have a rounded corner. When bending the pond, the corners may damage the film that is the outer body, so the thermoplastic Chamfering the corners of the body 110 can provide a highly reliable secondary battery. The material of the plastic body 110 may be any material that becomes soft at temperatures close to the skin surface temperature.

[0064] Also, if the surface of the thermoplastic object 110 is smooth, the thermoplastic object 110 may be in contact with the surface of the thermoplastic object 110. Because the internal structure and exterior body slide together, it is also possible to provide a secondary battery that is resistant to repeated bending. can.

[0065] The positive electrode 101 is a current collector (such as aluminum) having a positive electrode active material layer or the like on one or both sides thereof. The negative electrode 102 includes a negative electrode active material layer on one or both sides of a current collector (copper, etc.). The positive electrode 101 is electrically connected to a positive electrode lead 104. The negative electrode 102 is electrically connected to the negative electrode lead 105. The positive electrode lead 104 and the negative electrode lead 105 are also called lead electrodes or lead terminals. A part of the negative electrode lead 105 is disposed outside the exterior body. Charging and discharging occurs via positive lead 104 and negative lead 105 .

[0066] Here, the flow of current during charging of a secondary battery will be explained using FIG. 1(B). When a secondary battery is considered as a closed circuit, the movement of lithium ions and the flow of electric current are in the same direction. In secondary batteries that use lithium, the anode and cathode are charged and discharged. (cathode) is switched, and the oxidation and reduction reactions are switched, so the reaction potential The electrode with the higher reaction potential is called the positive electrode, and the electrode with the lower reaction potential is called the negative electrode. In this case, even if the battery is charging, discharging, or applying a reverse pulse current, Even when an electric current flows through it, the positive electrode is called the "positive electrode" or "+ electrode (plus electrode)" and the negative electrode is The negative electrode is called the "negative electrode" or "-electrode (minus electrode)". When the terms anode (positive electrode) and cathode (negative electrode) are used, the following occurs during charging and discharging: This can be confusing because the anode and cathode are the opposite. The term "cathode" is not used in this specification. When using the terms cathode and positive electrode, specify whether they are charging or discharging. It will also be indicated whether it corresponds to a positive pole (positive pole) or a negative pole (negative pole).

[0067] A charger is connected to the two terminals shown in FIG. 1(B) to charge the secondary battery 100. As the charging of the battery 100 progresses, the potential difference between the electrodes increases. Current flows from the external terminal (positive electrode lead 104) of 00 to the positive electrode current collector (positive electrode 101), and In the secondary battery 100, the 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 toward the external terminal (negative lead 105) of 00 is defined as the positive direction. In other words, the direction of the current is the same as the direction of the charging current.

[0068] In this embodiment, for the sake of simplicity, a pair of a positive electrode 101 and a negative electrode 102 is enclosed in an outer casing. In the example shown, the positive electrode 107 is housed in the positive electrode 107. In order to increase the capacity of the secondary battery, multiple positive electrode The negative electrode 101 and the negative electrode 102 may be housed in an exterior body 107 .

[0069] As shown in FIG. 2A, the exterior body 107 contains a thermoplastic object 110 and a positive electrode 101. In FIG. 2(A), a separator 103 and a negative electrode 102 are disposed. For simplicity, the exterior body 107, the positive electrode lead 104, and the negative electrode lead 105 are not shown. .

[0070] FIG. 2(A-1) is a cross-sectional view taken along dashed line A-A' in FIG. 2(A). 2(A) is a cross-sectional view taken along dashed line B-B' in FIG. A positive electrode 101, a separator 103, and a negative electrode 102 are provided. The width of the thermoplastic body 110 is the widest at the cross section B-B'. The thermoplastic object 110 is made to be slightly larger and wider than the data 103 .

[0071] In addition, in the cross sections AA' and BB', the negative electrode 102 is slightly wider than the positive electrode 101. The negative electrode 102 is made slightly larger than the positive electrode 101, for example, about 5% wider. do.

[0072] Furthermore, in the cross sections A-A' and B-B', the separator 103 is closer to the negative electrode 102 than the negative electrode 102. The separator 103 is slightly larger than the negative electrode 102, for example, about 5% wider. We are creating it quickly.

[0073] By forming the thermoplastic object 110 to be slightly larger than the separator 103, it is possible to prevent unintended The secondary battery or the electronic device in which the secondary battery is installed may be damaged by a large external force. This solves the problem of the radius of curvature becoming too small when the wire is bent beyond the limit. The size relationship between the plastic body 110 and the separator 103 is an essential component for achieving the above effect. The area relationship between the two can be reversed. The relationship may be changed depending on the design of the secondary battery or electronic device. It is.

[0074] When the secondary battery is charged, 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, This allows lithium ions to be efficiently inserted and suppresses the deposition of lithium on the surface of the negative electrode 102. Cut.

[0075] Materials for forming the separator 103 include cellulose (paper), nanocellulose, Cellulose nanofiber, polypropylene (PP), polyethylene (PE), polybutene Polypropylene, nylon, polyester, polysulfone, polyacrylonitrile, polyvinyl fluoride Porous insulators such as polyethylene and tetrafluoroethylene can be used. Alternatively, a membrane made of nonwoven fabric such as glass fiber or a composite of glass fiber and polymer fiber may be used.

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

[0077] In addition, in FIG. 2(A), an example in which a sheet-like separator 103 is used is shown, but a bag Alternatively, one separator may be folded and a separator may be placed between the folded separators. The electrode 104 may be disposed within the exterior body 107 so that the electrode (or negative electrode) is located therein.

[0078] FIG. 16A shows an example in which a pouch-shaped separator 103 is used. The positive electrode 101 is inserted through the opening, and the opening is then closed by, for example, welding with heat. When heat welding, in addition to welding all the sides of the bag in a line, weld the sides every 1 cm, The non-welded portions may be repeatedly welded in a broken line. This allows the electrolyte to penetrate well into the positive electrode 101 inside the capacitor 103.

[0079] In FIG. 16(B), a bag-shaped separator 103 is used to separate two positive electrodes 101a and 101b and two In this example, two negative electrodes 102a and 102b are formed in one pouch-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 materials on both the front and back surfaces. (Hereinafter, this will be referred to as double-sided coating.) However, in the structure of FIG. 16(B), An active material is applied to one side of each of the electrodes 101a and 101b (hereinafter, also referred to as one-side coating). Alternatively, the two surfaces on which the active material is not provided may face each other. When the surfaces of the active materials of the positive electrodes are coated on both sides (for example, when the positive electrodes 101a and 101b are coated on both sides), In the case where the active material surface of the positive electrode 101a and the active material surface of the positive electrode 101b come into contact with each other or The material surface and the metal surface (for example, the positive electrode 101a when the positive electrode 101a is coated on both sides) a and the metal surface of the positive electrode 101b) are in contact with each other. Metal surfaces (for example, the metal surface of the positive electrode 101a and the metal surface of the positive electrode 101b) come into contact with each other. In the case of a secondary battery, the static friction coefficient is low. The force can be relaxed by sliding at the interface where the metallic surfaces of the adjacent positive electrodes contact each other.

[0081] In the structure of FIG. 16(B), the negative electrodes 102a and 102b are coated on one side, and the negative electrode 102a The surface on which the active material is not provided faces the thermoplastic material 110, and the active material of the negative electrode 102b is not provided. It is also possible to have a structure in which one side faces the surface of an exterior body (not shown). For example, when the negative electrode 102a is coated on both sides, the surface of the active material of the negative electrode 102a and the heat When the plastic object 110 comes into contact with the active material surface (for example, when the negative electrode 102b is coated on both sides), In this case, the metal surface is in contact with the exterior body, as compared with the case where the active material surface of the negative electrode 102b is in contact with the exterior body. When the thermoplastic object 110 comes into contact with a surface (e.g., the metal surface of the negative electrode 102a) or when the metal surface When the metal surface of the negative electrode 102b (for example) comes into contact with the exterior body, the static friction coefficient becomes low. When a secondary battery deforms, the stress generated inside the battery is transferred between the metal surface and the thermoplastic material. The surface where 10 comes into contact and the surface where the metal surface and the exterior body come into contact can slide and be alleviated. .

[0082] In addition, the position of the thermoplastic object 110 is not limited to that shown in FIG. 2(A). For example, in FIG. As shown, a thermoplastic body 110 may be provided on the side in contact with the negative electrode 102. In response to this, the thermoplastic body 110 is closer to the surface of the human skin so as to efficiently transfer heat to the thermoplastic body 110. The thermoplastic object can be placed on the other side. ), and cross section B-B' are shown in Figure 2 (B-2). The design size concept is shown in Figure 2 ( A-1) and FIG. 2(A-2).

[0083] In addition, the number of thermoplastic objects 110 is not limited to one, and multiple objects may be used. For example, FIG. As shown in FIG. 1, a positive electrode 110 is disposed between a first thermoplastic body 110a and a second thermoplastic body 110b. Alternatively, the cathode may have a structure including a cathode 101, a separator 103, and an anode 102. In this case, The thermoplastic object can be arranged so that heat is transferred to the same extent. Section A-A' is shown in Figure 2 (C-1), and section B-B' is shown in Figure 2 (C-2). The concept is the same as that of FIG. 2(A-1) and FIG. 2(A-2), respectively.

[0084] The positive electrode active material used in the positive electrode active material layer of the secondary battery 100 has an olivine type crystal structure, There are composite oxides with a rock-salt crystal structure or a spinel crystal structure. For example, LiFeO 2 , LiCoO 2 , LiNiO 2 , LiMn 2 O 4 , V 2 O 5 , Cr 2 O 5 , MnO 2 Compounds such as:

[0085] Or a composite material (general formula LiMPO 4 (M is Fe(II), Mn(II), Co(I One or more of Ni(I), Ni(II) and Li(II) can be used. 4 Representative examples of As for LiFePO 4 , LiNiPO 4 , LiCoPO 4 , LiMnPO 4 , Life a Ni b PO 4 , Life a Cob PO 4 、LiFe a Mn b PO 4 、LiNi a Co b PO 4 、LiNi a Mn b PO 4 (a + b is 1 or less, 0 < a < 1, 0 < b < 1), LiF e c Ni d Co e PO 4 、LiFe c Ni d Mn e PO 4 、LiNi c Co d Mn e PO 4 (c + d + e is 1 or less, 0 < c < 1, 0 < d < 1, 0 < e < 1), LiFe f Ni g C o h Mn i PO 4 (f + g + h + i is 1 or less, 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 MSiO 4 (M is one or more of Fe(II), Mn(II ), Ni(II), 0 ≦ j ≦ 2) can be used. General formula L i 2-j MSiO 4 's representative examples include Li 2-j FeSiO 4 、Li 2-j NiSiO 4 、Li 2-j CoSiO 4 、Li 2-j MnSiO 4 、Li 2-j Fe k Nil SiO 4 、Li 2-j Fe k Co l SiO 4 、Li 2-j Fe k Mn l SiO 4 、Li 2-j N i k Co l SiO 4 、Li 2-j Ni k Mn l SiO 4 (k + l is 1 or less, 0 < k < 1, 0 < l < 1), Li 2-j Fe m Ni n Co q SiO 4 、Li 2-j Fe m Ni n Mn q SiO 4 、Li 2-j Ni m Co n Mn q SiO 4 (m + n + q is 1 or less, 0 < m < 1, 0 < n < 1, 0 < q < 1), Li 2-j Fe r Ni s Co t Mn u SiO 4 (r + s + t + u is 1 or less, 0 < r < 1, 0 < s < 1, 0 < t < 1, 0 < u < 1) and other lithium compounds can be mentioned.

[0087] Also, as the positive electrode active material, A x M 2 (XO 4 ) 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 of sodium The Lithium-ion type compound can be used. The Nasicon type compound is Fe 2 (MnO 4 ) 3 , Fe 2 (SO 4 ) 3 , Li 3 Fe 2 (PO 4 ) 3 In addition, as a positive electrode active material, , Li 2 MPO 4 F, Li 2 MP 2 O 7 , Li 5 MO 4 It is expressed by the general formula (M=Fe, Mn). The compound that is used is NaFeF 3 , FeF 3 Perovskite-type fluorides such as TiS 2 , Mo S 2 Metal chalcogenides (sulfides, selenides, tellurides), LiMVO 4 The opposite of Oxides with spinel-type crystal structure, vanadium oxides (V 2 O 5 , V 6 O 13 , L iV 3 O 8 etc.), manganese oxides, organic sulfur compounds, and other materials can be used.

[0088] In addition, the positive electrode active material is Li a Mn b M c O d Lithium manium can be expressed as A manganese-based composite oxide can be used. Here, the element M is selected from elements other than lithium and manganese. The selected metal element, silicon, or phosphorus is preferably used, and nickel is the preferred Further, when measuring the entire particle of the lithium manganese composite oxide, When the value is 0 <a / (b+c)<2、かつc>0 and 0.26≦(b+c) / d<0.5 is satisfied It is preferable that the total amount of metal, silicon, and other components of the lithium manganese composite oxide particles is 100%. The composition of phosphorus, etc. is measured, for example, using an ICP-MS (inductively coupled plasma mass spectrometer) The oxygen composition of the entire lithium manganese composite oxide particle can be determined by, for example, ED It can be measured using energy dispersive X-ray spectrometry (ICP- In combination with MS analysis, molten gas analysis and XAFS (X-ray absorption fine structure) analysis were used to evaluate the charge. The lithium manganese composite oxide is a compound oxide that contains at least lithium It refers to oxides containing thium and manganese, and also contains chromium, cobalt, aluminum, nickel, Iron, magnesium, molybdenum, zinc, indium, gallium, copper, titanium, niobium, silicon and may contain at least one element selected from the group consisting of silicon, silicon, and phosphorus. stomach.

[0089] In order to realize high capacity, the crystal structure, crystal orientation, or oxygen content of the surface layer and the center portion must be adjusted. It is preferable to use a lithium manganese composite oxide having regions with different amounts of manganese. In order to obtain a lithium manganese oxide, the composition formula is changed to Li a Mn b Ni c O d (1.6 ≦a≦1.848, 0.19≦c / b≦0.935, 2.5≦d≦3) Further, Li 1.68 Mn 0.8062 Ni 0.318 O 3 The formula is It is particularly preferable to use a lithium manganese composite oxide having the above-mentioned structure. , Li 1.68 Mn​0.8062 Ni 0.318 O 3 Lithium ma is represented by the formula Li-Zn composite oxide is a compound oxide in which the ratio (molar ratio) of the amount of raw materials is 2 CO 3 :MnCO 3 : Lithium manganese formed by mixing NiO=0.84:0.8062:0.318 Therefore, the lithium manganese composite oxide has the composition formula Li 1.68 M n 0.8062 Ni 0.318 O 3 However, the composition may deviate from this formula.

[0090] Lithium manganese composite oxide having regions with different crystal structures, crystal orientations or oxygen contents An example of a cross-section of a particle is shown in FIG.

[0091] As shown in FIG. 3(A), a crystalline structure, a crystal orientation, or an oxygen content of each region is different. The lithium manganese composite oxide is made up of a first region 331, a second region 332, and a third region 333. It is preferable that the second region 332 is at least 10 mm outside the first region 331. The outer side of the particle also contacts a part of the particle. The region 333 corresponds to the surface of the particle having the lithium manganese composite oxide. It is preferable.

[0092] As shown in FIG. 3B, the first region 331 is an area that is not covered by the second region 332. The second region 332 may have an area that is not covered by the third region 333. Also, for example, the first region 331 may have a region where the third region 333 is in contact with the first region 331. In addition, the first region 331 may be either the second region 332 or the third region 333. may have areas that are not covered.

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

[0094] For example, the compositions of the first region 331 and the second region 332 are measured separately, and the first region 331 a first region 332 having manganese, the element M, and oxygen; The atomic ratio of manganese, element M, and oxygen in the first region 331 is b1:c1:d 1, and the atomic ratio of manganese, element M, and oxygen in the second region 332 is b2:c2 :d2. In addition, the first region 331 and the second region 332 The composition of each component can be determined by, for example, EDX (energy dispersive X-ray diffraction) using a TEM (transmission electron microscope). When the measurement is performed by EDX, the lithium is Since it is difficult to measure the composition of the first region 331 and the second region 332, the difference in composition is Here, d1 / (b1+c1) is preferably 2.2 or more, It is more preferably 2.3 or more, and even more preferably 2.35 or more and 3 or less. In addition, d2 / (b2+c2) is preferably less than 2.2, and more preferably less than 2.1. More preferably, the ratio is 1.1 or more and 1.9 or less. Also, the entire lithium manganese composite oxide particle including the first region 331 and the second region 332 The composition preferably satisfies the above-mentioned condition 0.26≦(b+c) / d<0.5.

[0095] For example, the compositions of the first region 331 and the second region 332 are measured separately, and the first region 331 has lithium, manganese, the element M and oxygen, and the second region 332 has lithium, manganese, the element M and oxygen. the first region 331 having lithium, manganese, the element M, and oxygen; The atomic ratio of oxygen is represented by a1:b1:c1:d1, and the atomic ratio of lithium, manganese, and arsenic in the second region 332 is represented by a1:b1:c1:d1. The atomic ratio of gun, element M, and oxygen is expressed as a2:b2:c2:d2. The composition of each of the first region 331 and the second region 332 is, for example, TE Measurements are made using EDX (energy dispersive X-ray analysis) with a transmission electron microscope (M) It is sometimes difficult to measure the lithium composition using EDX. Therefore, in the following, the difference in composition between the first region 331 and the second region 332 is due to elements other than lithium. Here, d1 / (b1+c1) is preferably 2.2 or more, and 2.3 or more More preferably, d is 2.35 or more and 3 or less. 2 / (b2+c2) is preferably less than 2.2, more preferably less than 2.1. It is preferable that the ratio is 1.1 or more and 1.9 or less. The composition of the entire lithium manganese composite oxide particle including the region 331 and the second region 332 is the same as that described above. It is preferable that the above-mentioned condition 0.26≦(b+c) / d<0.5 is satisfied.

[0096] The manganese contained in the second region 332 is different from the manganese contained in the first region 331. The element M contained in the second region 332 may have a valence of 0.01 to 0.01. The element M may have a different valence from that of the element M.

[0097] More specifically, the first region 331 is made of lithium manganese having a layered rock salt type crystal structure. The second region 332 is preferably a composite oxide having a spinel type crystal structure. It is preferable that the lithium manganese composite oxide is a lithium manganese composite oxide having a lithium-manganese complex structure.

[0098] Here, when there is a spatial distribution in the composition of each region or the valence of an element, for example, The composition and valence of each of the regions are evaluated, and the average value is calculated, which may be used as the composition and valence of the region. stomach.

[0099] There may also be a transition layer between the second region 332 and the first region 331. A transition layer is, for example, a region where the composition changes continuously or stepwise. A transition layer is a region where the crystal structure changes continuously or stepwise. The second region 3 is a region in which the lattice constant of the crystal changes continuously or stepwise. A mixed layer may be provided between the first region 32 and the first region 331. Here, the mixed layer may be, for example, The mixed layer refers to a mixture of two or more crystals having different crystal orientations. For example, it refers to a mixture of two or more crystals having different crystal structures. For example, this refers to the mixture of two or more crystals with different compositions.

[0100] The third region 333 can be made of carbon or a metal compound. For example, cobalt, aluminum, nickel, iron, manganese, titanium, zinc, lithium Examples of metal compounds include oxides and fluorides of these metals. Some examples include:

[0101] Of the above, it is particularly preferable that the third region 333 contains carbon. Carbon has good electrical conductivity. Therefore, by using carbon-coated particles in the electrodes of secondary batteries, the resistance of the electrodes can be reduced, for example. In addition, since the third region 333 contains carbon, the resistance of the third region The second region 332 adjacent to the third region 333 can be oxidized. The graphene oxide may be reduced. Graphene and reduced graphene oxide are known to be highly conductive. It has excellent electrical properties and excellent physical properties, including high flexibility and mechanical strength. In addition, the lithium manganese composite oxide particles can be efficiently coated.

[0102] The third region 333 contains carbon such as graphene, and thus the lithium manganese The cycle characteristics of a secondary battery using the composite oxide as a positive electrode material can be improved.

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

[0104] In addition, the lithium manganese composite oxide has, for example, an average particle size of the primary particles of 5 nm or more. 0 μm or less, and more preferably 100 nm or more and 500 nm or less. In addition, the specific surface area is 5m 2 / g or more 15m 2 / g or less. The average particle size of the secondary particles is preferably 5 μm or more and 50 μm or less. Observation using a scanning electron microscope (SEM) or a transmission electron microscope (TEM), or laser diffraction and scattering methods The specific surface area can be measured by a particle size distribution meter or the like. It can be measured.

[0105] In addition to the above-mentioned positive electrode active material, the positive electrode active material layer contains a binder for improving the adhesion of the active material. The positive electrode active material layer may contain a binder, a conductive assistant for increasing the conductivity of the positive electrode active material layer, and the like.

[0106] In addition, the carrier ion is an alkali metal ion other than the lithium ion, an alkaline earth metal ion, etc. In the case of ions, instead of lithium, an alkali metal (e.g., sodium) is used as the positive electrode active material. Alkaline earth metals (e.g. calcium, strontium, barium, etc.), Aluminum, beryllium, magnesium, etc. may also be used.

[0107] The electrolytic solution is an electrolyte in which carrier ions are mobile and which are carrier ions. A material containing lithium ions is used. A typical example of the electrolyte is LiPF 6 , LiCl O 4 , LiAsF 6 , LiBF 4 , LiCF 3 SO 3 , Li(CF 3 SO 2 ) 2 N, Li (C 2 F 5 SO 2 ) 2 These electrolytes are lithium salts such as N. Two or more of them may be used in any combination and in any ratio.

[0108] As the solvent for the electrolyte, a material in which carrier ions can move is used. As the solvent, an aprotic organic solvent is preferable. Representative examples of the aprotic organic solvent include: Ethylene carbonate (EC), propylene carbonate, dimethyl carbonate, Diethyl carbonate (DEC), γ-butyrolactone, acetonitrile, dimethoxyethane , tetrahydrofuran, etc., one or more of which can be used. By using a polymeric material that gels as a solvent for the electrolyte, safety against leakage, etc. is improved. In addition, it is possible to make the secondary battery thinner and lighter. Examples include silicone gel, acrylic gel, acrylonitrile gel, and polyethylene glycol. Examples of gels include oxide-based gels, polypropylene oxide-based gels, and fluorine-based polymer gels. In addition, a flame-retardant and non-volatile ionic liquid (room-temperature molten salt) was used as the solvent for the electrolyte. Or, by using multiple batteries, the internal temperature of the secondary battery may rise due to an internal short circuit or overcharging. Even if the battery is in a fluid state, it can prevent explosion or fire of the secondary battery. Ionic liquids are salts and have high ion mobility (conductivity). In addition, ionic liquids are made up of cations and anions. The ionic liquids include ionic liquids containing the ethylmethylimidazolium (EMI) cation. ionic liquid, or N-methyl-N-propylpiperidinium (PP 13 ) cations Ionic liquids, etc.

[0109] In addition, instead of an electrolyte solution, solid electrolytes containing inorganic materials such as sulfides and oxides, and PEO A solid electrolyte having a polymer material such as polyethylene oxide can be used. When using a solid electrolyte, the installation of a separator or spacer is unnecessary. Since the liquid can be solidified, there is no risk of leakage, and safety is improved dramatically.

[0110] The negative electrode active material used in the negative electrode active material layer of the secondary battery 100 is a lithium dissolution / precipitation material. The material can be used to insert and extract lithium ions, and lithium metal, carbon-based Materials, alloy-based materials, etc. can be used.

[0111] Lithium metal has a low redox potential (-3.045 V vs. the standard hydrogen electrode) and is lightweight and and high specific capacity per volume (3860mAh / g and 2062mAh / cm, respectively). 3 ) is therefore preferable.

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

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

[0114] When lithium ions are inserted into graphite (when lithium-graphite intercalation compounds are formed), It has a low potential similar to that of lithium metal (0.1 to 0.3 V vs. Li / Li + This allows the lithium-ion secondary battery to exhibit a high operating voltage. Graphite has a relatively high capacity per unit volume, small volume expansion, is inexpensive, and is a lithium It is preferable since it has advantages such as higher safety compared to metals.

[0115] As a negative electrode active material, it is possible to carry out charge / discharge reactions by alloying / de-alloying reactions with lithium. When the carrier ion is a lithium ion, the alloy can be used. Examples of gold-based materials include Al, Si, Ge, Sn, Pb, Sb, Bi, Ag, Au, There are materials that contain at least one of Zn, Cd, In, Ga, etc. Such elements are carbon. The capacity is large compared to the elements, and silicon in particular has a dramatically high theoretical capacity of 4200mAh / g. For this reason, it is preferable to use silicon as the negative electrode active material. Examples of gold-based materials include Mg 2Si, Mg 2 Ge, Mg 2 Sn, SnS 2 , V 2 Sn 3 , FeSn 2 , CoSn 2 , Ni 3 Sn 2 , Cu 6 Sn 5 , Ag 3 Sn, Ag 3 Sb, Ni 2 MnSb, CeSb 3 , LaSn 3 , La 3 Co 2 Sn 7 , CoSb 3 , InSb , SbSn, etc. SiO is a powder of silicon oxide that contains silicon-rich parts. It refers to SiO y (2>y>0). For example, SiO is Si 2 O 3 , S 3 O 4 , or Si 2 Materials containing one or more selected from O, Si powder and Silicon oxide SiO 2 SiO also contains mixtures of other elements (carbon, nitrogen, iron, aluminum, etc.) In some cases, it contains ferrous metals such as niobium, copper, titanium, calcium, manganese, etc. , amorphous Si, polycrystalline Si, Si 2 O 3 , Si 3 O 4 , Si 2 O, SiO 2 Choose from It refers to a material that contains multiple SiO, and SiO is a colored material. x (X is 2 or more), they are colorless, transparent, or white, and can be distinguished. However, After making a secondary battery using SiO as the material, the battery is repeatedly charged and discharged. Therefore, when SiO is oxidized, SiO 2 In some cases, it may change into

[0116] In addition, the negative electrode active material is SiO, SnO, SnO 2 , titanium dioxide (TiO 2 ), Richie Lithium Titanium Oxide (Li 4 Ti 5 O 12 ), lithium-graphite intercalation compound (Li x C 6 ), Niobium pentoxide (Nb 2 O 5 ), tungsten oxide (WO 2 ), molybdenum oxide (MoO 2 ) and other oxides can be used.

[0117] In addition, the negative electrode active material is a complex nitride of lithium and transition metals, Li 3 Has N-type structure Li 3-x M x N (M=Co, Ni, Cu) can be used. For example, Li 2.6 Co 0.4 N 3 has a large charge / discharge capacity (900mAh / g, 1890mAh / cm 3 ) And preferable.

[0118] When a composite nitride of lithium and transition metals is used, the negative electrode active material contains lithium ions, so the positive electrode V that does not contain lithium ions as an active material 2 O 5 , Cr 3 O 8 Combine with other materials In addition, even when a material containing lithium ions is used as the positive electrode active material, The lithium ions contained in the positive electrode active material are first removed to make it the negative electrode active material. A complex nitride of lithium and a transition metal can be used.

[0119] In addition, a material that undergoes a conversion reaction can also be used as the negative electrode active material. For example, Lithium oxide (LiO), cobalt oxide (CoO), nickel oxide (NiO), iron oxide (FeO), etc. A transition metal oxide that does not undergo an alloying reaction with the negative electrode active material may be used. Further materials in which the reaction occurs include Fe 2 O 3 ,CuO,Cu 2 O, RuO 2 , Cr 2 O 3 Oxides such as CoS 0.89 , NiS, CuS and other sulfides, Zn 3 N 2 , Cu 3 N.G. e 3 N 4 Nitrides such as NiP 2 , FeP 2 , CoP 3 Phosphides such as FeF 3 , BiF 3 This also occurs with fluorides such as those mentioned above. Since the electric potential of the above fluorides is high, they are not used as positive electrode active materials. This is also fine.

[0120] In addition to the above-mentioned negative electrode active material, the negative electrode active material layer contains a binder for improving the adhesion of the active material. The negative electrode active material layer may contain a binder, a conductive assistant for increasing the conductivity of the negative electrode active material layer, and the like.

[0121] In this embodiment, an example of a small battery for use in a portable information terminal or the like is shown, but the present invention is not limited thereto. The present invention can be applied not only to small batteries but also to large batteries to be mounted on vehicles, etc.

[0122] Note that one embodiment of the present invention has been described in this embodiment. In the following, one embodiment of the present invention will be described. However, the embodiment of the present invention is not limited to these. That is, various inventive aspects are described in this and other embodiments. Therefore, one embodiment of the present invention is not limited to a specific embodiment. For example, one embodiment of the present invention As an example of the application of the present invention to a lithium ion secondary battery, In some cases, or depending on the circumstances, one aspect of the present invention is to Secondary battery, lead acid battery, lithium ion polymer secondary battery, nickel metal hydride battery, nickel nickel-cadmium battery, nickel-iron battery, nickel-zinc battery, silver oxide-zinc battery batteries, solid-state batteries, air batteries, zinc-air batteries, lithium-air batteries, primary batteries, capacitors, Or electric double layer capacitor, ultracapacitor, supercapacitor, lithium It may be applied to an ion capacitor, etc. Depending on the circumstances, one embodiment of the present invention may not be applied to a lithium ion secondary battery. For example, an example of a modified power storage device has been described as one embodiment of the present invention. The manner is not limited thereto. In some cases or depending on the situation, The power storage device may be configured so as not to deform, or may be configured so as not to bend. Alternatively, in some cases or depending on the situation, in one embodiment of the present invention, the power storage device is For example, in one embodiment of the present invention, a power storage device may be provided with a thermoplastic resin. However, one embodiment of the present invention is not limited to this. In some cases or depending on the situation, in one embodiment of the present invention, the power storage device may have various properties. Alternatively, in some cases, or depending on the circumstances, the present invention may provide an object having In one aspect, the thermoplastic object may have properties other than thermoplasticity.

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

[0124] (Embodiment 2) In the first embodiment, an example in which a sheet-shaped thermoplastic object is used is shown. In the present embodiment, An example will be shown in which a thermoplastic object having a different shape and an installation position from those in the first embodiment are used.

[0125] FIG. 4(A) shows an example of a schematic diagram of a secondary battery. Also, the internal structure surrounded by the exterior body of the secondary battery is shown. An example of the structure is shown in FIG. 4(B). In FIG. 4, the same reference numerals are used for the parts common to FIG. 1. For the sake of brevity, detailed description will be omitted here.

[0126] The secondary battery 400 according to one embodiment of the present invention includes a positive electrode 101 and a separator 10 inside an exterior body 107. 3, a negative electrode 102, a first thermoplastic body 410a, a second thermoplastic body 410b, It contains at least an electrolyte.

[0127] In this embodiment, the first thermoplastic body 410a and the second thermoplastic body 410b are The separator 103 is thicker than the separator 103 and has a rod shape.

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

[0129] The outer periphery of the exterior body 107 is bonded by thermocompression. The film used for the exterior body 107 has a layer made of polypropylene. Only the portion that is applied to the surface of the film and heat-pressed becomes the adhesive area.

[0130] The first thermoplastic body 410a and the second thermoplastic body 410b are bonded to the adhesive region 411 and the positive electrode When the battery is placed between the laminate of the battery 101, the separator 103, and the negative electrode 102, the battery 107 is preferably placed between the battery 101 and the separator 103. A cross-sectional shape that makes the step between the area overlapping the laminate and the area overlapping the adhesive area 411 gentler. Make it into a shape.

[0131] The materials used for the first thermoplastic body 410a and the second thermoplastic body 410b include: Any material that becomes soft at temperatures close to the skin surface temperature may be used. Therefore, it is necessary to select a thermoplastic object that is resistant to the electrolyte. Or, measures must be taken to prevent the thermoplastic object from coming into contact with the electrolyte. For example, The thermoplastic object may be covered with a film that is resistant to the electrolyte and has high thermal conductivity.

[0132] By providing a first thermoplastic body 410a and a second thermoplastic body 410b, a secondary electric Even if the secondary battery 400 is bent, no wrinkles are formed in the exterior film at the outer periphery of the secondary battery 400. It is possible to provide a configuration that is less susceptible to such damage.

[0133] In order to increase the capacity of the secondary battery 400, the positive electrode 101, the separator 103, the negative electrode When multiple combinations of layers of 102 are stacked and stored in an exterior body, the total thickness becomes thick. This causes a large difference in thickness between the outer periphery and the film, resulting in a step in the film of the exterior body. In order to ease the temperature rise, the first thermoplastic body 410a and the second thermoplastic body 410b are It is preferable to provide:

[0134] FIG. 4(A-1) is a cross-sectional view taken along dashed line AA' in FIG. 4(A).

[0135] In the cross section A-A', the negative electrode 102 is slightly wider than the positive electrode 101. The pole 102 is made slightly larger, for example, about 5% wider.

[0136] In the cross section A-A', the separator 103 is slightly wider than the negative electrode 102. The negative electrode 03 is made a size larger than the negative electrode 102, for example, about 5% wider.

[0137] FIG. 4(A-2) is a cross-sectional view taken along the dashed line BB' in FIG. 4(A). A positive electrode 101, a separator 103, and a second thermoplastic body 410a and a second thermoplastic body 410b are disposed between the positive electrode 101, the separator 103, and the second thermoplastic body 410b. and the negative electrode 102 is positioned therein.

[0138] The height of the first thermoplastic body 410a and the second thermoplastic body 410b is equal to the height of the positive electrode 101, the The upper exterior body 102 may be formed to have a thickness of about the same as that of the laminate of the negative electrode 102. 07 and the laminate of the positive electrode 101, the separator 103, and the negative electrode 102. It is preferable to form the cross-sectional shape so that the step in the area where the first heat exchanger overlaps with the body is gentle. The plastic body 410a and the second thermoplastic body 410b are in contact with the upper outer casing 107. For this reason, if the surface is formed smoothly without corners, the exterior body may be scratched. This can be suppressed.

[0139] FIG. 4(A-3) shows a combination of the thermoplastic object 110 described in the first embodiment with FIG. 4(A). FIG. 1 is a cross-sectional view taken along dashed line BB′ of an embodiment of the present invention. A first thermoplastic body 410a and a second thermoplastic body 410b are provided on the The positive electrode 101, the separator 103, and the negative electrode 102 are disposed between them.

[0140] Also, an example using two thermoplastic bodies, a first thermoplastic body 410a and a second thermoplastic body 410b, is shown. However, there is no particular limitation, and it may be used as a single U-shaped thermoplastic object 410. An example is shown in FIG. 4(C). Alternatively, a single frame-shaped thermoplastic object may be used.

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

[0142] (Embodiment 3) As one embodiment of the present invention, a thermoplastic material is provided on the surface of an electronic device equipped with a secondary battery. This embodiment mode can be appropriately combined with other embodiment modes.

[0143] FIG. 5 shows an example of a thermoplastic material provided on the surface of an electronic device equipped with a secondary battery. 5(A) is a perspective view of the electronic device, and FIG. 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. A thermoplastic object 504 is formed on the surface of the inner curved surface having a smaller radius of curvature among the two curved surfaces. do.

[0145] The electronic device 500 can be used as a wristwatch or a bracelet, for example. For example, it can be used as an anklet or a collar. do.

[0146] The support 501 may be made of any material as long as it has a flexibility that allows it to be wrapped around the body. is not particularly limited.

[0147] The secondary battery 502 may not have a thermoplastic body as described in the first and second embodiments. , it may also comprise a thermoplastic body.

[0148] The display unit 503 is, for example, an organic EL display formed using a flexible plastic substrate. The display unit 503 can be deformed according to the deformation of the support 501. For example, in addition to organic EL displays, electrophoretic displays ( Electronic paper) is also preferred.

[0149] The thermoplastic object 504 is not necessarily provided on the top surface of the electronic device 500. If the body heat is transferred to the body, the support may be provided inside the support, for example, a thermoplastic material. The surface of the heater may be covered with a material having good thermal conductivity.

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

[0151] (Embodiment 4) In this embodiment, the film surface is embossed to have a pattern on it. An example of producing a lithium ion secondary battery will be described.

[0152] First, a sheet made of a flexible substrate is prepared. The sheet is a laminate, and the metal film is Use a material that has an adhesive layer (also called a heat seal layer) on one or both sides. The adhesive layer is a heat-sealable resin film containing polypropylene, polyethylene, etc. In the embodiment, the sheet has a nylon resin on the surface of an aluminum foil, The back side of the metal foil is covered with an acid-resistant polypropylene layer and a laminated polypropylene layer. A sheet is used, which is then cut to prepare a film 60 as shown in FIG.

[0153] Then, the film 60 is embossed to form a film surface as shown in FIG. The unevenness is formed on the surface to form a visible pattern. The following shows an example of embossing, but the order is not limited to this. The embossing is performed before cutting the sheet. The sheet may be processed and then cut into the state shown in FIG. 6(B). Alternatively, the sheet may be cut after bending and thermocompression bonding.

[0154] The embossing process, which is a type of press working, will be described below.

[0155] FIG. 7 is a cross-sectional view showing an example of embossing. Note that embossing is a process similar to press processing. It is a type of embossing that presses an embossed roll with a rough surface against a film. This refers to a process to form unevenness on the film surface that corresponds to the unevenness of the embossed low. A roll is a roll with a pattern engraved on its surface.

[0156] FIG. 7(A) shows an example in which embossing is performed on one side of the film.

[0157] In FIG. 7A, an embossing roll 53 contacts one side of the film, and a The film 50 is sandwiched between the roll 54 and the film 50 in the direction of travel. The film is then fed to the printer at 58. It is being formed.

[0158] FIG. 7(A) shows an embossing roll 53 and a roll 54 (metal roll or elastic roll (rubber roll)). It is a combination of (e.g., 1)

[0159] FIG. 7(B) shows an example in which embossing is performed on both sides of the film.

[0160] In FIG. 7B, an embossing roll 53 contacts one side of the film, and a The film 51 is sandwiched between the embossing roll 55 which is in contact with the It is shown being sent out in the direction of travel 58.

[0161] FIG. 7(B) shows the male-handled embossing rolls 53 and 55 ( This is a combination of male and female patterns.

[0162] In addition, embossing is performed to raise a part of the surface of the film 51, and embossing is performed to make the surface recessed. The continuous unevenness forms a pattern on the surface of film 51.

[0163] In FIG. 7C, an embossing roll 56 contacts one side of the film, and a The film 52 is sandwiched between the embossing roll 57 which is in contact with the It is shown being sent out in the direction of travel 58.

[0164] FIG. 7C is also called Tip to Tip and shows an embossing roll 56 and its embossing The combination of roll 56 and embossing roll 57 with the same pattern is shown. The phases of the convex and concave parts are matched, and the pattern on the front and back of the film 52 is almost the same. It can be formed.

[0165] In addition, the method is not limited to using an embossing roll, and an embossing plate may be used. In addition, it is not limited to embossing, but can also be used to form relief on a part of the film. As long as it is legal.

[0166] In this embodiment, the film 60 is provided with projections and recesses on both sides to form a pattern, and the film 61 is provided with a projection and recess on the center. The structure is folded in the center and the three sides of the four sides excluding the folded part are sealed with an adhesive layer. do.

[0167] Next, the film 61 is folded along the dotted line in FIG. 6(B) to obtain the state shown in FIG. 6(C). do.

[0168] The secondary battery having a pattern with projections and recesses on the surface of the film 61 that serves as the exterior body is It can reduce the stress applied when bending. It can reduce the distortion caused by stress. This structure prevents damage (to the exterior body, etc.) when the secondary battery is bent or deformed. Therefore, long-term reliability can be ensured without any trouble.

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

[0170] (Embodiment 5) In this embodiment mode, an example of manufacturing a secondary battery using a current collector having a meandering portion will be described below.

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

[0172] Next, the positive electrode active material layer is selectively removed by laser light irradiation. This process narrows the area where the lead electrode is connected and narrows the area where the meandering part is narrow. Then, laser processing is performed. In this laser processing, both the positive electrode active material layer and the metal foil are In this example, the current collector is processed to draw the outline of the meandering portion, and the current collector is At this stage, the state shown in FIG. 8(A) can be obtained. FIG. 8(A) As shown in FIG. 1, a part of the current collector (the base part of the meandering pattern) is exposed, and the positive electrode active material layer 18a Thus, the positive electrode active material layer 18b is formed.

[0173] In addition, although the outer shape of the current collector was formed by laser processing here, a cutting device or punching machine may be used. After the metal foil is cut into the desired shape using a punching device, it is further processed by laser to create complex shapes. This may be a process for forming a current collector having a desired shape.

[0174] In addition, after forming an active material layer on one or both sides of the positive electrode current collector 12, laser processing is performed. The cut surface formed by irradiating the laser beam is preferably a surface that is provided with strong energy and is capable of collecting current. This is desirable because it allows the body and the active material layer to be firmly attached to each other.

[0175] As shown in FIG. 8(A), there are at least two narrow portions in the meandering part of the current collector. At least one portion (the root of the meandering pattern) is at the boundary between adjacent active material layers (positive electrode active material The positive electrode active material layer 18a and the positive electrode active material layer 18b overlap each other.

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

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

[0178] Next, the negative electrode active material layer is selectively removed by laser light irradiation. This is the narrow area that is connected to the lead electrode by the above process. Then, laser processing is performed. In this laser processing, the outline of the current collector with a meandering section is drawn, and the shape of the current collector is shaped. Complete.

[0179] FIG. 8C is a schematic top view of the negative electrode current collector 14 and the negative electrode active material layer 19. Figure 8(D) is a photograph taken while the sensor was held in the holder.

[0180] As shown in FIG. 8(A) and FIG. 8(C), the current collectors of both the positive and negative electrodes have a meandering portion. The meandering section can also be called the turning section. The meandering portion is a bent pattern shape including a linear pattern. A body shape where a part of the contour of the upper surface of the body repeats bending at 90 degrees or more twice is called a meandering shape. In addition, some of the contours of the top surface of the current collector are rectangular, triangular, S-shaped, etc. The meandering shape includes the bends. Note that the bends in the meandering shape do not have to repeat the same pattern. The shape may have irregular bends. Also, the shape may be cut to form the meanders. The part that is cut is called a slit.

[0181] When the positive electrode current collector and the negative electrode current collector are overlapped in a later process, the area overlapping with the slit of the negative electrode current collector For example, in the case of the current collector shown in FIG. 8, the positive electrode active material layer is located in the negative electrode current collector. Since the slit overlaps with a narrow portion of the meandering portion of the positive electrode current collector, the positive electrode active material layer If the negative electrode active material layer is present, the negative electrode active material layer will not be present in the area where the negative electrode active material layer overlaps the positive electrode active material layer. Since the negative electrode active material layer does not exist in the area overlapping with the positive electrode active material layer, problems may occur during the battery reaction. Specifically, the carrier ions coming out of the positive electrode active material layer are most likely to enter the slits. The carrier ions are concentrated in the negative electrode active material layer in a nearby area, and the carrier ions are precipitated on the surface of the negative electrode active material layer. Therefore, in the case of the positive electrode active material layer without the negative electrode active material layer in the overlapping region, in the case of FIG. The positive electrode active material layer at the narrow portion of the meandering portion of the positive electrode current collector is removed by irradiating it with laser light. Thus, the precipitation of carrier ions can be suppressed.

[0182] For the above reasons, the width of the slits on the positive and negative electrodes should be equal or approximately equal to the width of the slit on the positive electrode. By increasing the width of the slit in the positive electrode, the load on the overlapping area is reduced. It is possible to eliminate or reduce the positive electrode active material layer without the electrode active material layer. This makes it possible to suppress the precipitation of carrier ions on the surface of the active material.

[0183] Next, as shown in FIG. 9(A), the positive electrode current collector 12 is sandwiched between separators 13. A part 13a of the area of ​​the positive electrode collector 12 that does not overlap with the positive electrode collector 12 is adhered to the separator 13. The positive electrode current collector 12 is wrapped in the separator 13 as shown in FIG. When using polyvinylidene fluoride (PVDF), heat welding is performed at 190°C to 230°C. By doing so, adhesion can be achieved.

[0184] Next, as shown in FIG. 9(C), the positive electrode current collector 12 wrapped in the separator 13 and the negative electrode current collector At this time, a plurality of positive electrode current collectors 12 and negative electrode current collectors 14 are stacked. In this case, the positive electrode current collector 12 and the negative electrode current collector 14 wrapped with the separator 13 are preferably The electrode tabs of the positive electrode current collector 12 are stacked alternately, and the electrode tabs of the negative electrode current collector 14 are overlapped. The electrode tabs are preferably overlapped with each other. By stacking and electrically connecting the batteries, the capacity of the secondary battery can be increased.

[0185] The stacked separators 13, positive electrode current collectors 12, and negative electrode current collectors 14 are then bundled and fixed. It is preferable to fix the substrate in place using adhesive tape or a polyimide film coated with adhesive. This can be done using a resin tape or the like.

[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 another lead electrode. The bonding can be performed by ultrasonic welding. When the positive electrode current collectors 12 are stacked, one lead electrode and the electrode tabs of the multiple positive electrode current collectors 12 are connected to each other. A step of ultrasonically welding another lead electrode and the electrode tab portions of the multiple negative electrode current collectors 14 together This allows the process of ultrasonically welding the multiple positive electrode current collectors 12 to be performed simultaneously. Conduction between the negative electrode current collectors 14 is obtained.

[0187] The lead electrode connected to the positive electrode current collector 12 is made of aluminum or other material. The lead electrode connected to the negative electrode current collector 14 may be made of a material such as copper. Any material that can be used for a current collector may be used. The lead electrode has the same potential as the positive electrode current collector 12, and the same is true for the negative electrode. The usable materials can be used for the lead electrodes.

[0188] Next, as shown in Figs. 10(A) and (B), the periphery of the film 11 is heat-pressed, leaving two sides uncovered. As shown in FIG. 10(B), in this embodiment, one side of the film 11 is folded. Since the bent edge is the edge 11b, only one edge 11b of the film 1 is sealed in this step. In the area enclosed by 1, a separator 13, a positive electrode current collector 12, and a negative electrode current collector are stacked. It can hold 14.

[0189] The film 11 may be embossed in advance. This makes it possible to make the secondary battery more flexible.

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

[0191] Next, as shown in FIG. 10(D), an electrolyte solution 20 is injected into the area surrounded by the film 11. Then, while applying a vacuum, heat and pressure, the film is The remaining side 11d of the package 11 is sealed. These operations are carried out in a glove box or the like. The vacuum is drawn using a vacuum sealer, a liquid injection sealer, etc. In addition, by sandwiching the film 11 between two heatable bars of the sealer, The sealing can be performed by applying heat and pressure. The pressure can be applied at 0 kPa, heating at 190°C, and pressure at 0.1 MPa for 3 seconds.

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

[0193] In addition, the secondary battery that had undergone the aging treatment was opened once and gas generated by the aging treatment was removed. You can also drain the gas, add electrolyte, and reseal the battery. If gas is present, it can cause a bias in the battery reaction and lead to deterioration, so it is important to remove the gas and reseal the battery. 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 film 11 is used in the description, the method of sealing three sides in order has been described. The embodiment is not limited to this. When manufacturing a secondary battery having a shape other than a rectangular shape, the order and method of sealing may be changed as appropriate. can be changed.

[0195] The current collector having such a meandering pattern and the positive electrode active material layer at the base of the meandering pattern are partially By selectively removing the electrodes, a flexible battery can be realized.

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

[0197] (Embodiment 6) FIG. 11A is a schematic diagram of a device for charging electronic device 500 described in the third embodiment. For example, in a situation where a secondary battery needs to be rapidly charged, the secondary battery absorbs heat near body temperature. In such a case, the secondary battery may be pushed beyond its limit by an unintentional external force. If the wire is bent upward, the radius of curvature may become too small. This problem can be solved by providing a support base 1100.

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

[0199] During charging, the support base 1100 maintains heat on its surface close to body temperature, thereby supporting the The electronic device may be structured so that it is in close contact with the surface of the stand 1100. After the electronic device is in close contact with the electronic device, the heat retention may be discontinued.

[0200] Fig. 11(B) is another schematic diagram of a device for charging an electronic device equipped with a secondary battery. The 1100 has space from the top to the inside where electronic equipment can be stored.

[0201] Provide a highly thermally conductive material where the thermoplastic object is in contact with or in close proximity to the charger. It is also possible to provide a configuration that allows the heat of the secondary battery to be easily released to the outside.

[0202] The secondary battery is not required to be charged quickly, and the secondary battery is not at body temperature during charging. In the case where the heat does not exceed the temperature, it is not necessary to provide a support stand as in this embodiment.

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

[0204] (Embodiment 7) The electronic device has an antenna for wireless charging and performs wireless charging according to the Qi standard. In addition, electronic devices can wirelessly communicate data used for display with external devices. The communication device has:

[0205] The electronic device has a power supply control circuit and controls charging and discharging of the secondary battery.

[0206] Another example of electronic equipment is shown in FIG.

[0207] As an example of an electronic device that uses a flexible power storage device, there is a head-mounted Head-mounted display devices such as head-mounted displays and goggle-type displays, wrist-mounted display devices, etc. Stationary display device (also called a television or television receiver), desktop type and notebook type personal computers, computer monitors, digital cameras , digital video cameras, digital photo frames, electronic organizers, e-book terminals, electronic translation Machines, toys, microphones and other voice input devices, electric shavers, electric toothbrushes, microwave ovens High frequency heating devices, electric rice cookers, electric washing machines, vacuum cleaners, water heaters, electric fans, hair dryers Air conditioners such as humidifiers, dehumidifiers, and air conditioners, dishwashers, dish dryers, Clothes dryers, futon dryers, electric refrigerators, electric freezers, electric refrigerator-freezers, freezers for DNA storage Storage, flashlights, power tools, smoke detectors, gas alarms, burglar alarms and other alarm devices, industrial Robots, hearing aids, cardiac pacemakers, X-ray equipment, radiation measuring devices, electric massagers and dialysis machines and other health and medical equipment, mobile phones (also called mobile phones or mobile phone devices), Portable game machines, portable information terminals, lighting equipment, headphones, stereos, remote controllers clocks, table clocks, wall clocks, cordless telephone handsets, transceivers, pedometers, calculators , portable or stationary audio playback devices such as digital audio players, pachinko machines, etc. Examples include large game consoles.

[0208] In addition, the flexible energy storage device can be mounted on the inner or outer walls of a house or building, or on the inside or outside of a car. It is also possible to incorporate it along the curved surfaces of the interior or exterior of the vehicle.

[0209] FIG. 12A shows an example of a mobile phone. A mobile phone 7400 includes a housing 7401. In addition to the display unit 7402, operation buttons 7403, an external connection port 7404, The mobile phone 7400 is equipped with a speaker 7405, a microphone 7406, and the like. It has device 7407.

[0210] FIG. 12B shows the mobile phone 7400 in a curved state. When the 0 is deformed by an external force and curved as a whole, the storage device installed inside The bent power storage device 7407 is also bent. The power storage device 7407 is a laminated secondary battery (a laminated battery, a film-covered battery). The power storage device 7407 is fixed in a bent state. The power storage device 7407 has a lead electrode 7408 electrically connected to a current collector 7409. For example, the film of the exterior body of the power storage device 7407 is embossed. The device 7407 has a highly reliable structure even when bent. The 7400 has a slot for inserting a SIM card and a USB device such as a USB memory stick. A connector portion for connecting the sensor may be provided.

[0211] FIG. 12(D) shows an example of a bendable mobile phone. The state of the power storage device 7104 is shown in FIG. 1, a display unit 7102, an operation button 7103, and a power storage device 7104. The device 7104 has a lead electrode 7105 electrically connected to a current collector 7106 . For example, a press process is used to form a plurality of projections and recesses on the surface of the film of the exterior body of the power storage device 7104. The power storage device 7104 is highly reliable even if it is bent many times by changing the curvature. Furthermore, the mobile phone 7100 is configured to maintain the functionality of the SIM card. It has a slot for connecting a USB memory stick and a connector for connecting a USB device. This is also fine.

[0212] In addition, by installing a bendable power storage device in a vehicle, it is possible to Next-generation clean energy vehicles such as electric vehicles (EV) and plug-in hybrid vehicles (PHEV) This will also enable agricultural machinery and motorized bicycles, including electrically assisted bicycles. , motorcycles, electric wheelchairs, electric carts, small or large boats, submarines, fixed-wing aircraft and rotorcraft It can be used on moving objects such as aircraft, rockets, satellites, space probes, planetary probes, and spacecraft. It is also possible to mount a power storage device that can be used to store electricity.

[0213] FIG. 13 illustrates an example of a vehicle using one embodiment of the present invention. 100 is an electric vehicle that uses an electric motor as a power source for running; or A hybrid vehicle that can select between an electric motor and an engine as a power source for driving. When installing a laminated secondary battery in a vehicle, multiple laminates are used. A battery module that integrates rechargeable batteries with a nate structure is installed in one or more locations. By using one embodiment of the present invention, the power storage device itself can be made smaller and lighter. For example, a curved battery device can be installed on the inside of the tire to realize a vehicle with a long driving range. In addition, the power storage devices can be arranged in various shapes in the gaps between the vehicles, and the trunk can be easily stored. The vehicle 8100 can secure a space for storing electricity and a passenger space inside the vehicle. The power storage device not only drives the electric motor 8106, but also the headlights 8101 and the lamps. Power can be provided to a light emitting device such as a room light (not shown).

[0214] In addition, the power storage device may be used for displaying information such as a speedometer and a tachometer of the automobile 8100. The power storage device can supply power to the navigation device of the automobile 8100. The present invention can provide power to semiconductor devices such as power distribution systems.

[0215] The automobile 8200 shown in FIG. 13B is a power storage device of the automobile 8200. The device can be charged by receiving power from an external charging facility using a contactless charging method or other methods. FIG. 13B shows a diagram of a charging device 8021 installed on the ground and a storage device 8200 installed in the vehicle. The charging device is shown being charged via a cable 8022. The power supply method and connector standards are specified as appropriate, such as CHAdeMO (registered trademark) or Combo. The charging device 8021 may be a charging station provided in a commercial facility. For example, a plug-in system that allows the device to be connected to an external power supply The power storage device 8024 mounted on the automobile 8200 can be charged by the above. This can be done by converting AC power to DC power via a conversion device such as a CDC converter. do.

[0216] Although not shown, a power receiving device is mounted on the vehicle and receives power from a ground power transmitting device in a non-contact manner. In this non-contact power supply method, a power transmission device is installed on the road or exterior wall. By incorporating this technology, charging can be done not only when the vehicle is stopped but also while it is moving. Using this method, power can be transmitted between two vehicles. A solar cell may be provided in the storage unit to charge the power storage device when the vehicle is stopped or traveling. To supply power through contact, an electromagnetic induction method or a magnetic resonance method can be used.

[0217] According to one aspect of the present invention, the degree of freedom in the installation location of the power storage device is increased, and vehicle design can be made more efficient. Furthermore, according to one embodiment of the present invention, the power storage device itself can be made smaller and lighter. If the power storage device itself can be made smaller and lighter, it will contribute to reducing the weight of the vehicle, thus improving the cruising range. In addition, the vehicle-mounted power storage device can be used as a power supply source other than for the vehicle. In this case, it is possible to avoid using commercial power sources during peak power demand periods. It is possible.

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

[0219] In addition, the contents (or even a part of the contents) described in one embodiment may be used in the embodiment. Another content (or a part of the content) described in the embodiment, and / or one or more other embodiments The application, combination, or replacement of the contents (or part of the contents) described in the form It is possible to do the following:

[0220] The contents described in the embodiments are explained in detail with reference to various figures in each embodiment. This refers to the content that is stated or stated using the text in the specification.

[0221] In addition, a figure (or a part thereof) described in one embodiment may be different from another part of the figure, Another figure (or a part thereof) described in the embodiment, and / or one or more By combining with the figure (or a part of it) described in another embodiment of the present invention , and many more diagrams can be constructed. [Explanation of symbols]

[0222] 11 Film 11b 1 side 11c 1 side 11d 1 side 12 Positive electrode current collector 13 Separator 13a: A part of the area 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 Cathode 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 body 110 Thermoplastic objects 110a First thermoplastic object 110b Second thermoplastic object 331 First Area 332 Second Area 333 The Third Region 400 Secondary battery 410a First thermoplastic object 410b Second thermoplastic object 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 Case 7102 Display section 7103 Operation button 7104 Energy storage devices 7105 Lead electrode 7106 Current collector 7400 Mobile Phone 7401 Case 7402 Display section 7403 Operation button 7404 External connection port 7405 Speaker 7406 Mike 7407 Energy storage devices 7408 Lead electrode 7409 Current collector 8021 Charging device 8022 Cable 8024 Electricity storage device 8100 Automobiles 8101 Headlight 8106 Electric Motor 8200 Automobiles

Claims

1. A positive electrode current collector having an L-shape in top view, When viewed from above, the corners of the L-shape of the positive electrode current collector include a plurality of first corners having an angle of approximately 90 degrees and a second corner having an angle of approximately 270 degrees, When viewed from above, the second corner portion is located at a bent portion of the L-shape, When viewed from above, the positive electrode current collector has a shape that is recessed inward at the second corner portion, The recessed shape is a secondary battery having a curved portion.

2. A negative electrode current collector having an L-shape when viewed from above, When viewed from above, corners of the L-shape of the negative electrode current collector include a plurality of first corners having an angle of approximately 90 degrees and a second corner having an angle of approximately 270 degrees, When viewed from above, the second corner portion is located at a bent portion of the L-shape, When viewed from above, the negative electrode current collector has a shape that is recessed inward at the second corner portion, The recessed shape is a secondary battery having a curved portion.

3. A positive electrode current collector having an L-shape in top view, When viewed from above, the L-shape of the positive electrode current collector has a first side that is located inside the L-shape and extends in a first direction, and a second side that is located inside the L-shape and extends in a second direction perpendicular to the first direction, When viewed from above, corners of the L-shape of the positive electrode current collector include a plurality of first corners each having an angle of approximately 90 degrees, and a second corner that is located between the first side and the second side and has an angle of approximately 270 degrees, When viewed from above, the positive electrode current collector has a shape that is recessed inward at the second corner portion, The recessed shape is a secondary battery having a curved portion.

4. A negative electrode current collector having an L-shape when viewed from above, When viewed from above, the L-shape of the negative electrode current collector has a first side that is located inside the L-shape and extends in a first direction, and a second side that is located inside the L-shape and extends in a second direction perpendicular to the first direction, when viewed from above, corners of the L-shape of the negative electrode current collector include a plurality of first corners each having an angle of approximately 90 degrees, and a second corner that is located between the first side and the second side and has an angle of approximately 270 degrees, When viewed from above, the negative electrode current collector has a shape that is recessed inward at the second corner portion, The recessed shape is a secondary battery having a curved portion.

Images