Battery control unit

Abstract

To provide a lithium ion storage battery or an electronic apparatus that has flexibility and high safety.SOLUTION: A lithium ion storage battery has flexibility. The lithium ion storage battery has an internal structure and a sheath. The internal structure has at least a first laminated body and a second laminated body. The first laminated body has a first current collector, and the second laminated body has a second current collector. A surface of the first current collector has a first region in which no electrode active material is formed, and a surface of the second current collector has a second region in which no electrode active material is formed. The sheath wraps the internal structure. At least a part of the first region is in contact with at least a part of the second region. A surface of the current collector in which no electrode active material is formed has a low friction coefficient. When such a surface faces a similar surface, these slide on each other in response to the deformation of the storage battery, resulting in stress relief. In order to be adapted to the deformation, a space 118 may be provided inside the storage battery.SELECTED DRAWING: Figure 5

Description

Technical Field

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

[0002] Note that one aspect of the present invention is not limited to the above technical field. The invention disclosed in this specification etc. The technical field of one aspect relates to an object, a method, or a manufacturing method. Or, one aspect of the present invention relates to a process, a machine, a manufacture, or a composition (composition of matter). Therefore, more specifically, the technical field of one aspect of the present invention disclosed in this specification includes, as an example, semiconductor devices, display devices, liquid crystal display devices, light emitting devices, lighting devices , storage batteries, storage devices, their driving methods, or their manufacturing methods. can be cited.

Background Art

[0003] In recent years, various storage batteries such as lithium ion batteries, lithium ion capacitors, air batteries, fuel cells, etc. have been actively developed. In particular, lithium ion batteries with high output and high energy density are used in portable information terminals such as mobile phones, smartphones, and notebook personal computers , electronic devices such as portable music players and digital cameras, or medical devices , next-generation clean energy vehicles such as hybrid vehicles (HEVs), electric vehicles (EVs), or plug-in hybrid vehicles (P HEVs), stationary storage batteries, etc. With the development of the semiconductor industry and the increasing demand for energy conservation, their demand has rapidly expanded and they have become indispensable in modern society. Furthermore, in recent years, expectations for flexible devices or wearable devices have been increasing, and they have flexibility to deform following the deformation of the device. to have. There is an urgent need to develop a lithium-ion battery, that is, a flexible battery, and some development has already started (Patent Document 1).

[0004] A lithium-ion battery has a positive electrode, a negative electrode, a separator, an electrolyte, and an outer case that covers these. Generally, in a lithium-ion battery, a positive electrode mixture containing a positive electrode active material that occludes and releases lithium ions is applied to both sides of a positive electrode current collector made of a metal such as aluminum, and a negative electrode mixture containing a negative electrode active material that occludes and releases lithium ions is applied to both sides of a negative electrode current collector made of copper or the like. Also, a separator is interposed between these positive and negative electrodes to insulate them, and the positive and negative electrodes are electrically connected to a positive electrode terminal and a negative electrode terminal provided on the outer case. The outer case has a fixed shape such as a cylindrical shape or a

[0005]

Prior Art Documents

Summary of the Invention

Problems to be Solved by the Invention

[0006] When a flexible lithium-ion battery is a laminated lithium-ion battery, the stress applied to the battery varies depending on each part of the laminated structure with deformation. For example, when a laminated lithium-ion battery is deformed so as to be wound around an axis, the laminated structure inside the battery is subjected to compressive stress near the axis and tensile stress far from the axis.

[0007] When the structures inside the storage battery are integrated in this way, as the storage battery deforms, the stress generated in each part has no room to relax. If the deformation of the storage battery is repeated, fatigue ( damage) will eventually accumulate in the internal laminated structure and may lead to destruction.

[0008] In addition, not only the internal laminated structure, but also as the number of deformations of the storage battery increases, fatigue (damage) accumulates in each member of the battery and the exterior body that holds the electrolyte. Also, since the deformation state of the internal structure is different from that of the exterior body, for example, when the deformation stress on the internal structure exceeds the degree that the exterior body can tolerate, the internal structure may be subjected to deformation stress. In this case, the internal structure directly applies stress to the exterior body, and fatigue (damage) accumulates in the exterior body. As the accumulation of fatigue (damage) progresses, eventually the exterior body or the sealing structure is damaged, and there may be a problem that air enters the inside of the storage battery. When a lithium-ion storage battery is damaged and air enters, the internal members of the storage battery may react with moisture in the air or generate heat and catch fire, and may even lead to serious accidents such as explosions.

[0009] In view of the above, one aspect of the present invention is to provide a storage battery with flexible characteristics, in which damage to the exterior body due to deformation is suppressed. Or, one aspect of the problem is to provide a storage battery in which damage to the internal structure due to deformation is suppressed. Or, one aspect of the problem is to provide a storage battery having an exterior body that can tolerate deformation of the internal structure. Or, one aspect of the problem is to realize ensuring the safety of a flexible storage battery.

[0010]

[0011] Another aspect of the present invention aims to provide a highly safe flexible lithium-ion battery or an electronic device. Or, another aspect of the present invention aims to provide a novel lithium-ion battery, or a novel electronic device, etc.

[0012] Note that the description of these problems does not prevent the existence of other problems. Note that one aspect of the present invention does not necessarily need to solve all of these problems. Note that other problems will become apparent from the descriptions in the specification, drawings, claims, etc., and it is possible to extract these other problems from the descriptions in the specification, drawings, claims, etc.

[0013] One aspect of the present invention has an internal structure and an exterior body. The internal structure has at least a first laminate and a second laminate. The first laminate has a first current collector, and the second laminate has a second current collector. The surface of the first current collector has a first region where no electrode active material is formed, and the surface of the second current collector has a second region where no electrode active material is formed. The exterior body wraps the internal structure, and at least a part of the

[0014] first region is in contact with at least a part of the second region. It is a flexible lithium-ion battery. Also, another aspect of the present invention has an internal structure and an exterior body. The internal structure has at least a first laminate and a second laminate. The first laminate has It has a region, and the exterior body encloses an internal structure and a void, and at least a part of the first region is in contact with at least a part of the second region. The first laminate and the second laminate can slide relative to each other. By sliding, the internal structure can occupy at least a part of the region of the void and is a flexible lithium-ion battery.

[0015] Also, one aspect of the present invention has an internal structure and an exterior body. The internal structure has at least a first laminate and a second laminate. The first laminate has a first current collector, and the second laminate has a second current collector. The surface of the first current collector has a first region where no electrode active material is formed, and the surface of the second current collector has a second region where no electrode active material is formed. The exterior body encloses the internal structure and the void, and at least a part of the first region is in contact with at least a part of the second region. By sliding, the internal structure can occupy at least a part of the region of the void, and the internal structure can be deformed about a first axis and the void satisfies the formula (1) for the length A of the outer edge of the cross-sectional shape in a plane perpendicular to the first axis. It is a flexible lithium-ion battery.

[0016]

Number

[0017] However, in formula (1), L represents the length of the cross-sectional shape of the internal structure in the plane, T represents the thickness of the cross-sectional shape of the internal structure in the plane, and r 2 represents the distance from the plane of the internal structure farthest from the first axis to the first axis.

[0018] ​In one aspect of the present invention, further, a flexible lithium ion battery having an electrolytic solution may be used. Also, in one aspect of the present invention, further, having an electrolytic solution, the voids may be occupied by the electrolytic solution, and a flexible lithium ion battery may be used. Also , in one aspect of the present invention, the first current collector is a positive electrode current collector, and the second current collector is a positive electrode current collector, and a flexible lithium ion battery may be used. Also, in one aspect of the present invention the first current collector is a negative electrode current collector, and the second current collector is a negative electrode current collector, and a flexible lithium ion battery may be used.

[0019] Also, an electronic device having a flexible lithium ion battery according to one aspect of the present invention, a display, and an operation button may be used.

Advantages of the Invention

[0020] One aspect of the present invention can provide a battery in which damage to the exterior due to deformation is suppressed in a flexible battery. Or, a battery in which damage to internal structures due to deformation is suppressed can be provided. Or, a battery having an exterior that can tolerate deformation of internal structures can be provided. Or, ensuring safety in a flexible battery can be achieved.

[0021] Also, one aspect of the present invention can provide a highly safe flexible lithium ion battery or an electronic device. Or, one aspect of the present invention can provide a novel lithium ion battery

[0022] , or a novel electronic device or the like.

[0022] Note that the description of these problems does not prevent the existence of other problems. Note that one Aspects are not required to solve all of these problems. Other problems will become apparent from the descriptions in the specification, drawings, claims, etc., and it is possible to extract other problems from the descriptions in the specification, drawings, claims, etc.

Brief Description of the Drawings

[0023]

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Mode for Carrying Out the Invention

[0024] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it will be easily understood by those skilled in the art that its form and details can be variously changed. Also, the present invention is not construed as being limited to the description content of the embodiments shown below.

[0025] In each of the drawings described in this specification, the positive electrode, negative electrode, active material layer, separator, exterior body, etc. The sizes of the respective components such as the size and thickness are exaggerated for the sake of clarity of the individual descriptions. Therefore, each component is not necessarily limited to its size, nor is it limited to the relative sizes between the components.

[0026] Also, in this specification and the like, ordinal numbers such as first, second, and third are used for convenience and do not indicate the order of steps or the vertical positional relationship. Therefore, for example, "the first" can be appropriately replaced with "the second" or "the third" and so on for explanation. In addition, the ordinal numbers described in this specification and the like may not match the ordinal numbers used to specify an aspect of the present invention.

[0027] In the configuration of the present invention described in this specification and the like, the same reference numerals are commonly used for the same part or parts having the same function among different drawings, and the repeated description thereof is omitted. Also, when referring to parts having the same function, the hatching patterns may be the same, and they may not be particularly labeled with reference numerals.

[0028] In this specification, flexibility refers to the property that an object is flexible and can be bent. It is a property that the object can be deformed in response to an external force applied to the object, and the presence or absence of elasticity or the ability to restore to the original shape before deformation is not a concern. A flexible storage battery can be deformed in response to an external force. A flexible storage battery can be used while being fixed in a deformed state, can be repeatedly deformed and used, or can be used in a non-deformed state. Also, in this specification and the like, the inside of the exterior body refers to the region surrounded by the exterior body in a lithium-ion storage battery, and structures such as the positive electrode, negative electrode, active material layer, separator, and electrolyte are included. It is an existing area.

[0029] In addition, the contents described in the embodiments for carrying out the present invention can be used in appropriate combinations. It is possible.

[0030] (Embodiment 1) In the present embodiment, a lithium-ion battery 110 according to an aspect of the present invention and a method for manufacturing the same will be described. will be described.

[0031] FIG. 1 is a diagram showing a lithium-ion battery 110 according to an aspect of the present invention. The lithium ion battery 110 has an internal structure 117 wrapped by an exterior body 116. The internal structure 117 has an electrode and a separator, and the electrode is electrically connected to a lead electrode 115. continued.

[0032] FIG. 2 is a cross-sectional view of the lithium-ion battery 110 according to an aspect of the present invention taken along line A1-A2 in FIG. 1 and an enlarged view thereof. The lithium-ion battery 110 described in the present embodiment has, as shown in FIG. 2, an electrolytic solution 107 and, as the internal structure 117, a first laminate 100a, a second laminate 100b, a third laminate 100c, and a fourth laminate 100d. has. Note that the number of laminates of the lithium-ion battery 110 described in the present embodiment is mainly four, but is not limited thereto. Each laminate has a negative electrode current collector 101, a negative electrode active material layer 102, a separator 103, a positive electrode active material layer 104, and a positive electrode current collector 105. has, as shown in FIG. 2, an electrolytic solution 107 and, as the internal structure 117, a first laminate 100a, a second laminate 100b, a third laminate 100c, and a fourth laminate 100d. has. Note that the number of laminates of the lithium-ion battery 110 described in the present embodiment is mainly four, but is not limited thereto. Each laminate has a negative electrode current collector 101, a negative electrode active material layer 102, a separator 103, a positive electrode active material layer 104, and a positive electrode current collector 105. has. Note that the number of laminates of the lithium-ion battery 110 described in the present embodiment is mainly four, but is not limited thereto. Each laminate has a negative electrode current collector 101, a negative electrode active material layer 102, a separator 103, a positive electrode active material layer 104, and a positive electrode current collector 105. has. Note that the number of laminates of the lithium-ion battery 110 described in the present embodiment is mainly four, but is not limited thereto. Each laminate has a negative electrode current collector 101, a negative electrode active material layer 102, a separator 103, a positive electrode active material layer 104, and a positive electrode current collector 105.

[0033] In addition, in the lithium-ion battery 110 described in the present embodiment, as shown in the enlarged view of FIG. 2, the first laminate 100a to the fourth laminate 100d each have the same laminate As shown in the figure, the first laminate 100a to the fourth laminate 100d each have the same laminate Although it is a structure, the stacking order of the layers constituting each laminate is in an alternating reverse relationship with each other. However, each laminate is not limited to having the same stacking structure as each other.

[0034] In the lithium-ion battery 110 described in this embodiment, in the first laminate 1 The surface of the current collector of the 00a positive electrode where the active material is not formed is in contact with the surface of the current collector of the positive electrode of the second laminate 100b where the active material is not formed, and the surface of the current collector of the negative electrode of the second laminate 100b where the active material is not formed is in contact with the surface of the current collector of the negative electrode of the third laminate 100c where the active material is formed The surface of the current collector of the negative electrode of the third laminate 100c where the active material is not formed is in contact with the surface of the current collector of the negative electrode of the fourth laminate 100d where the active material is not formed is in contact. However, in the lithium-ion battery 110 according to one aspect of the present invention, not all the laminates are limited to being in contact with each other's current collectors.

[0035] Since each current collector is a thin-film member made of a metal material as described later, the surface is extremely flat and has a small coefficient of friction. However, on the surface where the active material layer is formed, generally speaking, the surface of the current collector where the active material is not formed has a shape with larger irregularities, has a large coefficient of friction, and depending on the composition of the material forming the active material layer, it may exhibit adhesiveness to the structure in contact with the surface. That is, inside each laminate, since the current collector and the separator are stacked via the active material layer,

[0036] the friction between each layer is large, and all the structures constituting the laminate can be handled as a single entity. Unless a force of a certain magnitude or more is applied from the outside, each layer will not separate from each other. ​​It will not be separated. On the other hand, in each laminate, the surfaces of the current collectors are in contact with each other, and since the surface of each current collector has a low coefficient of friction, each laminate can easily slide relative to each other in response to an external force. Since the surface has a low coefficient of friction, each laminate can easily slide relative to each other in response to an external force.

[0037] In the flexible laminated lithium-ion battery 110 according to one aspect of the present invention, when the lithium-ion battery 110 is deformed, the exterior body and the internal structures are also deformed, and stress is applied due to the deformation. Here, the state of the internal structure of the laminated lithium-ion battery before and after deformation will be described with reference to FIG. 3. When the lithium-ion battery 110 is deformed, the exterior body and the internal structures are also deformed, and stress is applied due to the deformation. Here, the state of the internal structure of the laminated lithium-ion battery before and after deformation will be described with reference to FIG. 3.

[0038] FIG. 3(A) shows a cross-sectional view of the internal structure of the laminated lithium-ion battery 110 before deformation. FIGS. 3(B) and 3(C) show cross-sectional views of the internal structure of the laminated lithium-ion battery 110 in a deformed state. FIG. 3(D) is an enlarged view of a part of FIG. 3(B), and FIG. 3(E) is an enlarged view of a part of FIG. 3(C). In FIG. 3, 100a to 100d indicate each laminate. Although the number of laminates is 4 in FIG. 3, the number of laminates is not limited to this. FIG. 3(A) shows a cross-sectional view of the internal structure of the laminated lithium-ion battery 110 before deformation. FIGS. 3(B) and 3(C) show cross-sectional views of the internal structure of the laminated lithium-ion battery 110 in a deformed state. FIG. 3(D) is an enlarged view of a part of FIG. 3(B), and FIG. 3(E) is an enlarged view of a part of FIG. 3(C). In FIG. 3, 100a to 100d indicate each laminate. Although the number of laminates is 4 in FIG. 3, the number of laminates is not limited to this. FIG. 3(D) is an enlarged view of a part of FIG. 3(B), and FIG. 3(E) is an enlarged view of a part of FIG. 3(C). In FIG. 3, 100a to 100d indicate each laminate. Although the number of laminates is 4 in FIG. 3, the number of laminates is not limited to this. In FIG. 3, 100a to 100d indicate each laminate. Although the number of laminates is 4 in FIG. 3, the number of laminates is not limited to this.

[0039] First, FIG. 3(B) shows a case where the friction between the laminates is large and no sliding occurs between the laminates even when the lithium-ion battery 110 is deformed, and the laminates are deformed integrally. FIG. 3(D) is an enlarged view of a part of FIG. 3(B). It represents a case where the friction between the laminates is large and no sliding between the laminates due to deformation occurs. Due to the deformation, tensile stress is generated in some of the laminates while compressive stress is generated in another part of the laminates, so different stresses are applied to each laminate, but these cannot be eliminated. FIG. 3(B) shows a case where the friction between the laminates is large and no sliding occurs between the laminates even when the lithium-ion battery 110 is deformed, and the laminates are deformed integrally. FIG. 3(D) is an enlarged view of a part of FIG. 3(B). It represents a case where the friction between the laminates is large and no sliding between the laminates due to deformation occurs. Due to the deformation, tensile stress is generated in some of the laminates while compressive stress is generated in another part of the laminates, so different stresses are applied to each laminate, but these cannot be eliminated. Due to the deformation, tensile stress is generated in some of the laminates while compressive stress is generated in another part of the laminates, so different stresses are applied to each laminate, but these cannot be eliminated.

[0040] ​​​​ When the magnitude of the deformation exceeds the limit, the difference in stress applied to each laminate becomes too large, and each laminate undergoes irreversible delamination. Or, the stress applied to each layer constituting each laminate also becomes too large, causing damage such as cracks and fractures in each layer. Even when the magnitude of the deformation does not exceed the limit, repeated deformation will still cause such problems due to the accumulation of stress-induced damage. In any case, it becomes a serious problem for the function of the lithium-ion battery 110 and it can no longer withstand further use.

[0041] On the other hand, FIG. 3(C) shows a case where the friction between each laminate is small, for example, because the surfaces of the current collectors where the active material is not formed are in contact with each other between the laminates. Also, FIG. 3(E) is an enlarged view of a part of FIG. 3(C). When the friction between each laminate is small, the stress applied to each laminate in response to the deformation of the lithium-ion battery 110 is relaxed by the sliding between the laminates. Therefore, even if the lithium-ion battery 110 is greatly deformed, the generated stress is relaxed by sliding, so delamination is less likely to occur between the laminates. Or, the stress applied to each layer constituting each laminate is also relaxed, so the damage (damage) given to each layer becomes small and cracks and fractures are also less likely to occur. Furthermore, even when deformation is repeated many times, since the structure is such that stress is easily relaxed, the accumulation of damage is also small.

[0042] The lithium-ion battery according to one aspect of the present invention has small friction between each laminate, and each laminate can slide relative to each other in response to the deformation of the battery, so damage to the exterior due to deformation is suppressed.

[0043] The lithium-ion battery according to one aspect of the present invention has small friction between each laminate, and each laminate can slide relative to each other in response to the deformation of the battery, so damage to the exterior due to deformation is suppressed. It becomes a battery. Or, it becomes a storage battery in which damage to the internal structure due to deformation is suppressed. Therefore , it is possible to ensure the safety of the flexible storage battery.

[0044] By the way, in the lithium-ion storage battery according to one aspect of the present invention, each laminate can slide with each other, and damage due to deformation is suppressed, but it cannot be deformed infinitely large. This is because another problem occurs as the degree of deformation of the storage battery increases.

[0045] This problem will be described with reference to FIGS. 4 and 5. FIG. 4(A) shows a lithium ion storage battery 110 according to one aspect of the present invention, and FIG. 4(B) shows a cross-sectional structure along the broken line B1-B2 in FIG. 4(A). In the lithium-ion storage battery according to one aspect of the present invention, each laminate can slide with each other, but the storage battery has a lead electrode 115 for supplying power to the outside, and since the lead electrode 115 is connected to a plurality of current collectors, it is desirable that each laminate is fixed to each other at the end on the side where the lead electrode 115 exists. . When the ends are not fixed, when the storage battery is deformed, different amounts of sliding occur in each laminate, so that stress is generated in the lead electrode 115 to which the current collectors of each laminate are connected due to the difference in the amount of sliding. This is the reason.

[0046] The state of change in the cross-sectional shape accompanying the deformation of the lithium-ion storage battery 110 in which each laminate is fixed to each other at one end is shown in FIG. 5. First, FIG. 5(A) shows the cross-sectional structure of the lithium-ion storage battery before deformation. In this figure, the number of laminates is 4, but in the lithium-ion storage battery according to one aspect of the present invention, the number of laminates is not limited to 4. As shown in FIG. 5(A), the number of laminates is 4, but in the lithium-ion storage battery according to one aspect of the present invention, the number of laminates is not limited to 4. In the lithium-ion storage battery according to one aspect of the present invention, the number of laminates is not limited to 4. As shown in FIG. 5(A), The exterior body can be made larger than the size sufficient to enclose all of the internal laminate . By doing so, a void 118 (actually, the region occupied by the electrolyte) is created inside the storage battery , allowing room for the exterior body and the laminate to slide relative to each other and preventing unexpected damage to the exterior body and the laminate .

[0047] Fig. 5(B) shows the cross-sectional structure of the deformed lithium-ion storage battery 110. On the side with the lead electrode 11 5, the laminates are fixed to each other, while in other parts, the laminates slide relative to each other, resulting in the cross-sectional structure shown in Fig. 5(B). Here, as can be understood from Fig. 5(B) , as the degree of deformation of the lithium-ion storage battery increases, the void (the region occupied by the electrolyte) 118 inside the storage battery becomes smaller due to the change in its cross-sectional shape. Furthermore, when the storage battery attempts to deform more than shown in Fig. 5(B), the void is exhausted , causing interference with the exterior body, and eventually the laminate may apply stress to the exterior body, resulting in damage to the exterior body or the laminate . Therefore, it is desirable to provide a void 11 8 inside the storage battery according to the assumed magnitude of deformation of the storage battery.

[0048] On the other hand, if the void 118 is made too large, it will cause an increase in the volume that is not directly related to the capacity of the storage battery, resulting in a decrease in the capacity value per unit volume of the storage battery, which becomes a problem.

[0049] The void is provided by making the length of the exterior body in the cross-section shown in Fig. 5(A) longer than the necessary length to cover the internal structure. From the assumed magnitude of deformation applied to the storage battery , it is possible to derive the size of the void necessary to continuously cover the internal structure without interference. In addition, the length of the exterior body required to provide a void of that size can be derived.

[0050] Therefore, the following describes a lithium-ion battery having flexibility that can prevent damage to the exterior body due to deformation of the battery and can minimize a decrease in capacity per unit volume due to an increase in voids.

[0051] <Shape Changes and Void Settings of Flexible Lithium-Ion Batteries> First, the shape changes of a flexible lithium-ion battery will be described. For the sake of clarity in the description, a schematic diagram of the outer ring shape of the internal structure (the combined structure of all the laminates) of the battery in Fig. 5(A) is shown in Fig. 6(A). That is, Fig. 6(A) is a diagram showing the outer ring shape of the internal structure 117 of the lithium-ion battery before deformation. Also, a schematic diagram of the outer ring shape of the internal structure 117 of the lithium-ion battery in Fig. 5(B) is shown in Fig. 6(B). That is, Fig. 6(B) is a diagram showing the outer ring shape of the internal structure 117 of the deformed lithium-ion battery 110. In this figure, the end portion far from the center of curvature 1101 of the internal structure is designated as 1105, the end portions far from the center of curvature 1101 of the internal structure are respectively designated as 1103 and 1105, the end portions close to the center of curvature of the internal structure are respectively designated as 1102 and 1104, and the point close to the center of curvature of the internal structure is designated as 1106.

[0052] In Fig. 6(A), let the length of the laminate in the cross-section (for example, the length between 1102 and 1104) be L, and the thickness of the internal structure (for example, the length between 1102 and 1103) be T. Next, Fig. 6(B) shows a lithium-ion battery that has been deformed to the extent that the voids are used up. It is a diagram showing the cross-sectional structure of the internal structure 117. In FIG. 6(B), starting from the center of curvature 11 01, the distance (radius of the arc) with the end 1103 of the internal structure 117 on the side far from the center of curvature 1101 as the endpoint is set as r 2 . Further, starting from the center of curvature 1101, the distance (radius of the arc) to the end 1102 of the internal structure on the side close to the center of curvature 1101 is set as r 1 and so on.

[0053] First, the length around the outer ring shape of the internal structure 117 in the cross-section of FIG. 6(A) is 2L + 2 T. Next, consider the length of the outer ring shape of the internal structure in the cross-section of FIG. 6(B). First, the thickness of the internal structure (the length between 1104 and 1105) at one end where each laminate is fixed to each other does not change before and after deformation, so it is T.

[0054] Next, the lengths of the part close to the center of curvature of the internal structure (the arc between 1102 and 1104) and the part far from the center of curvature (the arc between 1103 and 1105) are also L because they do not change before and after the deformation of the storage battery. In the lithium-ion storage battery according to one aspect of the present invention, since each laminate can slide relative to each other, each laminate slides relative to each other in response to the deformation of the storage battery and the stress is relaxed, so the lengths of both parts do not change.

[0055] Therefore, the change in the length around the outer ring shape of the internal structure 117 accompanying the deformation of the storage battery is obtained by examining the length of the remaining part (between 1102 and 1103). Here, an explanation will be given for the point 1106 on the side close to the center of curvature of the internal structure. Regarding the point 1106, the straight line connecting the end 1103 on the side far from the center of curvature of the internal structure and the center of curvature 1101, and the internal Take the intersection with the side closer to the center of curvature of the outer ring shape of the structure. Then, the center of curvature 1101 is also the center of curvature of the arc (the arc between 1102 and 1104), which is the shape of the side closer to the center of curvature of the inner structure. Therefore, the arc and the straight line connecting the end 1103, which is on the side farther from the center of curvature of the inner structure, and the center of curvature 1101 are perpendicular at the point 1106. Also, since the arc between the end 1102 and the point 1106 has a small central angle, it can be approximated by a straight line. Therefore, when connecting the end 1103, the end 1102, and the point 1106, a right triangle is formed. Thus, the length between the end 1102 and the end 1103 can be obtained by using the lengths of the other two sides of the triangle according to the Pythagorean theorem. First, the length between the point 1106 and the end 1103 is the thickness of the inner structure 117, so it is T. Next, the length between the point 1106 and the end 1102 is the length obtained by subtracting the length of the arc between the point 1106 and the end 1104 from the length L of the arc connecting the end 1102 and the end 1104. Therefore, consider the length of the arc L between the point 1106 and the end 1104. The length of an arc is the value obtained by multiplying the product of the diameter and the circumference ratio π by the ratio of the magnitude of the central angle occupied in 360°. That is, L is represented by the following formula (2). Here, r

[0056] represents the radius of the arc, which is the shape of the side closer to the center of curvature of the inner structure, and θ is the central angle of the arc.

[0057] 1

[0058] 1

[0059]

Equation

[0060] 1 ​​​​​​​​​​represents the central angle. By the way, the length of the part of the internal structure far from the center of curvature (the arc between 1103 and 1105 is L. Since this part is an arc with a central angle of θ and a radius of r 2 , similarly, the following formula (3) holds.

[0061]

Number

[0062] Here, when applying formula (3) to formula (2), the following formula (4) holds.

[0063]

Number

[0064] Therefore, in the right triangle connecting end 1103, end 1102, and point 1106, if the length of the hypotenuse is T 1 , according to the Pythagorean theorem, the following formula (5) holds.

[0065]

Number

[0066] When applying formula (4) to formula (5), the following formula (6) holds for the length of T 1 .

[0067]

Number

[0068] Furthermore, the radius of the outer ring shape arc of the internal structure on the side far from the center of curvature 1101 is r 2 , and the radius of the outer ring shape arc of the internal structure on the side close to the center of curvature 1101 is r 1 , and the difference between them is the thickness T of the internal structure. Therefore, r ​1 is the value obtained by subtracting T from r. Therefore, T in Equation (6 2 ) is represented by the following Equation (7). ) minus T 1 is represented by the following Equation (7).

[0069]

Equation

[0070] In the state before the lithium-ion battery deforms, the length between the end 1103 and the end 1102 is the thickness T of the internal structure. The length between the end 1103 and the end 110 2 in the deformed state is T 1 . Therefore, due to the deformation of the lithium-ion battery, the increase in the length between the end 1103 and the end 1102 is T 1 -T and becomes the value represented by the following Equation (8).

[0071]

Equation

[0072] That is, it is desirable that a gap sufficient to allow this increase is provided inside the battery. In short , in the cross-section shown in FIG. 6, the length inside the outer casing is 2L + 2T, which is the length of the outer edge of the internal structure before deformation , plus the increase due to deformation, which is T 1 -T . In other words, based on the thickness and length of the internal structure, the size of the gap for preventing damage to the outer casing of the battery can be derived from the desired radius of curvature as the magnitude of deformation of the battery .

[0073] In conclusion, when the lithium-ion battery 110 is deformed by the axis that is the center of curvature , the length of the cross-section of the outer casing in the plane perpendicular to the axis is the outer ring shape of the internal structure 117 during deformation​ 2L + T + T in terms of length 1 It may be set to the above length. When the length of the exterior body at that time is A, , A satisfies the following formula (1).

[0074]

Number

[0075] Note that the technical idea also solves the problems existing only in the lithium-ion battery according to one aspect of the present invention, in which the friction between the laminated bodies is small and each laminated body slides relative to each other in response to the deformation of the storage battery and is released from stress.

[0076] Next, a lithium-ion battery according to one aspect of the present invention will be described.

[0077] ≪Configuration of positive electrode≫ First, the positive electrode will be described. The positive electrode includes a positive electrode active material layer 104 and a positive electrode current collector 105.

[0078] As the positive electrode active material used for the positive electrode active material layer 104, a material capable of inserting and extracting carriers such as lithium ions can be used. For example, a lithium-containing material having an olivine-type crystal structure, , a layered rock salt-type crystal structure, or a spinel-type crystal structure can be mentioned.

[0079] Representative examples of the lithium-containing material having an olivine-type structure (general formula LiMPO 4 (M is Fe(II), Mn( II), Co(II) or Ni(II))) include LiFePO 4 , Li NiPO 4 , LiCoPO 4 , LiMnPO 4 , LiFe a Ni b PO4 , LiFe a C o b PO 4 , LiFe a Mn b PO 4 , LiNi a Co b PO 4 , LiNi a Mn b PO 4 (a + b is less than or equal to 1, 0 < a < 1, 0 < b < 1), LiFe c Ni d Co e PO 4 , Li Fe c Ni d Mn e PO 4 , LiNi c Co d Mn e PO 4 (c + d + e is less than or equal to 1, 0 < c < 1, 0 < d < 1, 0 < e < 1), LiFe f Ni g Co h Mn i PO 4 (f + g + h + i is less than or equal to 1, 0 < f < 1, 0 < g < 1, 0 < h < 1, 0 < i < 1), etc.

[0080] For example, lithium iron phosphate (LiFePO 4 ) has good balance in terms of safety, stability, high capacity density, high potential , the presence of lithium ions that can be extracted during initial oxidation (charging), etc., which are required for the cathode active material, so it is preferred.

[0081] Examples of lithium-containing materials having a layered rock salt crystal structure include lithium cobalt oxide (LiCoO 2 ), LiNiO 2 , LiMnO 2 , Li 2 MnO 3 , LiNi0.8 Co 0.2 O 2 such as NiCo-based (general formula: LiNi x Co 1-x O 2 (0 < x < 1)), L iNi 0.5 Mn 0.5 O 2 such as NiMn-based (general formula: LiNi x Mn 1-x O 2 (0 < x < 1)), LiNi 1 / 3 Mn 1 / 3 Co 1 / 3 O 2 such as NiMnCo-based (also referred to as NMC. General formula: LiNi also. General formula: LiNi x Mn y Co 1-x-y O 2 (x > 0, y > 0, x + y < 1 )) can be mentioned. Furthermore, Li(Ni 0.8 Co 0.15 Al 0.05 )O 2 , Li 2 MnO 3 -LiMO 2 (M is Co, Ni or Mn), etc. can also be mentioned.

[0082] In particular, LiCoO 2 is preferred because it has advantages such as a large capacity, being more stable in the air compared to LiNiO 2 , and being thermally more stable compared to LiNiO . 2

[0083] Examples of lithium-containing materials having a spinel-type crystal structure include, for example, LiMn 2 O 4 , L i 1+x Mn 2-x O 4 , Li(MnAl) 2 O 4 , LiMn 1.5 Ni 0.5 O4 etc. can be cited.

[0084] LiMn 2 O 4 For a lithium-containing material having a spinel-type crystal structure containing manganese such as a small amount of lithium nickelate (LiNiO 2 or LiNi 1-x MO 2 (M = Co, Al, etc.) ) is mixed, there are advantages such as suppressing the elution of manganese and suppressing the decomposition of the electrolytic solution, which is preferable. desirable.

[0085] Also, as the positive electrode active material, a compound represented by the general formula Li (2-j) MSiO 4 (M is Fe(II), Mn (II), Co(II), or Ni(II)) (j is 0 or more and 2 or less) can be used. As representative examples of the general formula Li MSiO (2-j) are 4 Li ( 2-j) FeSiO 4 Li (2-j) NiSiO 4 Li (2-j) CoSiO 4 L i (2-j) MnSiO 4 Li (2-j) Fe k Ni l SiO 4 Li (2-j) Fe k Co l SiO 4 Li (2-j) Fe k Mn l SiO 4 Li (2-j) Ni k Co l SiO 4 Li (2-j) Ni k Mnl 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) etc. are mentioned.

[0086] Also, as the positive electrode active material, A x M 2 (XO 4 ) 3 (A is Li, Na, or Mg)(M is Fe, Mn, Ti, V, Nb, or Al)(X is S, P, Mo, W, As, or , Si) represented by the general formula of the NASICON type compound can be used. The NASICON type compound as, Fe 2 (MnO 4 ) 3 , Fe 2 (SO 4 ) 3 , Li 3 Fe 2 (PO 4 ) 3 etc. are mentioned. Also, as the positive electrode active material, Li 2 MPO 4 F, Li 2 MP2 O 7 , Li 5 M O 4 (M is Fe or Mn), a compound represented by the general formula NaFeF 3 , FeF 3 etc. Perovskite-type fluoride, TiS 2 , MoS 2 Metal chalcogenides such as sulfides, selenium , telluride), LiMVO 4 Lithium-containing materials with an inverse spinel crystal structure such as Vanadium oxide (V 2 O 5 , V 6 O 13 , LiV 3 O 8 etc.), manganese oxide, Materials such as organosulfur can be used.

[0087] In addition, the carrier ions are alkali metal ions other than lithium ions, alkaline earth metal ions, etc. In the case of group ions, lithium is used instead of lithium in the above compounds and oxides as the positive electrode active material. , alkali metals (e.g., sodium and potassium), alkaline earth metals (e.g., calcium For example, tungsten, strontium, barium, beryllium, magnesium, etc. may be used. For example, NaFeO 2 Ya, Na 2 / 3 [Fe 1 / 2 Mn 1 / 2 ]O 2 Sodium-containing The layered oxide can be used as the positive electrode active material.

[0088] In addition, a material in which a plurality of the above materials are combined may be used as the positive electrode active material. A solid solution of the above materials can be used as the positive electrode active material. Co 1 / 3 Mn 1 / 3 Ni 1 / 3O 2 and Li 2 MnO 3 using a solid solution thereof as a positive electrode active material is possible.

[0089] The positive electrode active material is preferably one having an average particle diameter of primary particles of 50 nm or more and 100 μm or less. .

[0090] The positive electrode active material, together with the negative electrode active material, plays a central role in the battery reaction of the storage battery and is a substance that releases and absorbs carrier ions. In order to increase the life of the storage battery, it is preferably a material having a small capacity related to the irreversible reaction of the battery reaction, and preferably a material having high charge and discharge efficiency.

[0091] Since the active material is in contact with the electrolyte, if the active material reacts with the electrolyte and the active material is lost and deteriorated due to the reaction, the capacity of the storage battery decreases. Therefore, in order to realize a storage battery with less deterioration, it is desirable that such a reaction does not occur in the storage battery.

[0092] As the conductive assistant for the electrode, acetylene black (AB), graphite (carbon) particles, carbon nanotubes, graphene, fullerene, etc. can be used.

[0093] The conductive assistant can form an electric conduction network in the electrode. The conductive assistant can maintain the electric conduction path between the positive electrode active materials. By adding the conductive assistant to the positive electrode active material layer, a positive electrode active material layer 101 having high electric conductivity can be realized.

[0094] Also, as the binder, in addition to typical polyvinylidene fluoride (PVDF), polyimide ​​​​​​​​​, polytetrafluoroethylene, polyvinyl chloride, ethylene propylene diene poly mer, fluororubber, polymethyl methacrylate, polyethylene, nitrocellulose, etc. can be used .

[0095] The content of the binder with respect to the total amount of the positive electrode active material layer 104 is preferably 1 wt% or more and 10 wt% or less , more preferably 2 wt% or more and 8 wt% or less, and still more preferably 3 wt% or more and 5 wt% or less. Further, the content of the conductive assistant with respect to the total amount of the positive electrode active material layer 101 is preferably 1 wt% or more and 10 wt% or less, and more preferably 1 wt% or more and 5 wt% or less.

[0096] When forming the positive electrode active material layer 104 using a coating method, the positive electrode active material, binder, conductive assistant and dispersion medium are mixed to prepare an electrode slurry, which is then coated on the positive electrode current collector 105 and dried .

[0097] Note that for the positive electrode current collector 105, metals such as stainless steel, gold, platinum, aluminum, titanium, etc., and alloys thereof, etc., materials with high conductivity and that do not alloy with carrier ions such as lithium can be used . Also, an aluminum alloy added with an element that improves heat resistance such as silicon, titanium, neodymium, scandium, molybdenum, etc. can be used. Also , it may be formed of a metal element that reacts with silicon to form a silicide. Metal elements that react with silicon to form a silicide include zirconium, titanium, hafnium, vanadium , niobium, tantalum, chromium, molybdenum, tungsten, cobalt, nickel, etc . The positive electrode current collector can appropriately use shapes such as foil-like, plate-like (sheet-like), net-like, punching metal-like, expanded metal-like, etc . ​​

[0098] Note that a positive electrode active material layer 104 may be provided on one side of the positive electrode current collector 105, and no positive electrode active material layer may be provided on the other side. In that case, in a state where the positive electrode active material layer is not provided, the surface of the positive electrode current collector 105 is flat and has a small coefficient of friction. Therefore, when the surface of the positive electrode current collector contacts the surface of another positive electrode current collector on which the positive electrode active material layer is not provided, the two current collectors can slide relative to each other according to the stress. In the above state where the positive electrode active material layer is not provided, the surface of the positive electrode current collector 105 is flat and has a small coefficient of friction. Therefore, when the surface of the positive electrode current collector contacts the surface of another positive electrode current collector on which the positive electrode active material layer is not provided, the two current collectors can slide relative to each other according to the stress. In the above state where the positive electrode active material layer is not provided, the surface of the positive electrode current collector 105 is flat and has a small coefficient of friction. Therefore, when the surface of the positive electrode current collector contacts the surface of another positive electrode current collector on which the positive electrode active material layer is not provided, the two current collectors can slide relative to each other according to the stress. In the above state where the positive electrode active material layer is not provided, the surface of the positive electrode current collector 105 is flat and has a small coefficient of friction. Therefore, when the surface of the positive electrode current collector contacts the surface of another positive electrode current collector on which the positive electrode active material layer is not provided, the two current collectors can slide relative to each other according to the stress. In the above state where the positive electrode active material layer is not provided, the surface of the positive electrode current collector 105 is flat and has a small coefficient of friction. Therefore, when the surface of the positive electrode current collector contacts the surface of another positive electrode current collector on which the positive electrode active material layer is not provided, the two current collectors can slide relative to each other according to the stress.

[0099] The positive electrode of the lithium-ion battery can be manufactured by the above steps.

[0100] ≪Configuration of Negative Electrode≫ Next, the negative electrode will be described. The negative electrode includes a negative electrode active material layer 102 and a negative electrode current collector 101. The steps for forming the negative electrode will be described below. The steps for forming the negative electrode will be described below.

[0101] As the negative electrode active material used for the negative electrode active material layer 102, examples of carbon-based materials include graphite, graphitizable carbon (soft carbon), non-graphitizable carbon (hard carbon), carbon nanotubes, graphene, carbon black, etc. Examples of graphite include artificial graphite such as mesocarbon microbeads (MCMB), coke-based artificial graphite, pitch-based artificial graphite, and natural graphite such as spheroidized natural graphite. Also, the shape of graphite includes flaky and spherical shapes, etc. Examples of carbon-based materials include graphite, graphitizable carbon (soft carbon), non-graphitizable carbon (hard carbon), carbon nanotubes, graphene, carbon black, etc. Examples of graphite include artificial graphite such as mesocarbon microbeads (MCMB), coke-based artificial graphite, pitch-based artificial graphite, and natural graphite such as spheroidized natural graphite. Also, the shape of graphite includes flaky and spherical shapes, etc. Examples of carbon-based materials include graphite, graphitizable carbon (soft carbon), non-graphitizable carbon (hard carbon), carbon nanotubes, graphene, carbon black, etc. Examples of graphite include artificial graphite such as mesocarbon microbeads (MCMB), coke-based artificial graphite, pitch-based artificial graphite, and natural graphite such as spheroidized natural graphite. Also, the shape of graphite includes flaky and spherical shapes, etc. Examples of carbon-based materials include graphite, graphitizable carbon (soft carbon), non-graphitizable carbon (hard carbon), carbon nanotubes, graphene, carbon black, etc. Examples of graphite include artificial graphite such as mesocarbon microbeads (MCMB), coke-based artificial graphite, pitch-based artificial graphite, and natural graphite such as spheroidized natural graphite. Also, the shape of graphite includes flaky and spherical shapes, etc. Examples of carbon-based materials include graphite, graphitizable carbon (soft carbon), non-graphitizable carbon (hard carbon), carbon nanotubes, graphene, carbon black, etc. Examples of graphite include artificial graphite such as mesocarbon microbeads (MCMB), coke-based artificial graphite, pitch-based artificial graphite, and natural graphite such as spheroidized natural graphite. Also, the shape of graphite includes flaky and spherical shapes, etc. Examples of carbon-based materials include graphite, graphitizable carbon (soft carbon), non-graphitizable carbon (hard carbon), carbon nanotubes, graphene, carbon black, etc. Examples of graphite include artificial graphite such as mesocarbon microbeads (MCMB), coke-based artificial graphite, pitch-based artificial graphite, and natural graphite such as spheroidized natural graphite. Also, the shape of graphite includes flaky and spherical shapes, etc.

[0102] As the negative electrode active material, in addition to carbon-based materials, materials capable of performing charge and discharge reactions through alloying and dealloying reactions with lithium can also be used. For example, materials containing at least one of Ga, Si, Al, Ge, Sn, Pb, Sb, Bi, Ag, Zn, Cd, In, etc. can be used. Such elements have a larger capacity compared to carbon, and in particular, silicon has a theoretical As the negative electrode active material, in addition to carbon-based materials, materials capable of performing charge and discharge reactions through alloying and dealloying reactions with lithium can also be used. For example, materials containing at least one of Ga, Si, Al, Ge, Sn, Pb, Sb, Bi, Ag, Zn, Cd, In, etc. can be used. Such elements have a larger capacity compared to carbon, and in particular, silicon has a theoretical As the negative electrode active material, in addition to carbon-based materials, materials capable of performing charge and discharge reactions through alloying and dealloying reactions with lithium can also be used. For example, materials containing at least one of Ga, Si, Al, Ge, Sn, Pb, Sb, Bi, Ag, Zn, Cd, In, etc. can be used. Such elements have a larger capacity compared to carbon, and in particular, silicon has a theoretical As the negative electrode active material, in addition to carbon-based materials, materials capable of performing charge and discharge reactions through alloying and dealloying reactions with lithium can also be used. For example, materials containing at least one of Ga, Si, Al, Ge, Sn, Pb, Sb, Bi, Ag, Zn, Cd, In, etc. can be used. Such elements have a larger capacity compared to carbon, and in particular, silicon has a theoretical A high capacity of 4200 mAh / g is preferable. As alloy-based materials using such elements, , for example, Mg 2 Si, 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. are available. .

[0103] In addition, as the negative electrode active material, SiO, SnO, SnO 2 , titanium dioxide (TiO 2 ), lithium titanate (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.

[0104] In addition, as the negative electrode active material, Li 3 with an N-type structure, which is a complex nitride of lithium and transition metals, Li 3-x M x N (M is Co, Ni or Cu) can be used. For example, Li 2 .6 Co 0.4 N 3 has a large charge-discharge capacity (900 mAh / g, 1890 mAh / cm 3 ) is shown and is preferable.

[0105] When using a complex nitride of lithium and a transition metal, since the negative electrode active material contains lithium ions, V that does not contain lithium ions as the positive electrode active material 2 O 5 , Cr 3 O 8 and other materials can be combined . Even when using a material containing lithium ions as the positive electrode active material, by previously desorbing the lithium ions contained in the positive electrode active material, a complex nitride of lithium and a transition metal can be used as the negative electrode active material.

[0106] In addition, a material that undergoes a conversion reaction can also be used as the negative electrode active material. For example, transition metal oxides such as cobalt oxide (CoO), nickel oxide (NiO), and iron oxide (FeO), which do not undergo an alloying reaction with lithium, may be used as the negative electrode active material. As materials that undergo a conversion reaction, furthermore, Fe O , CuO, Cu 2 O 3 , RuO 2 , Cr 2 O 2 3 and other oxides, sulfides such as CoS 0.89 , NiS, CuS, nitrides such as Zn 3 N 2 , Cu 3 N, G e 3 N 4 and other nitrides, phosphides such as NiP 2 , FeP 2 , CoP 3 and other phosphides, FeF 3 , BiF 3 This also occurs with fluorides such as

[0107] As an example, the negative electrode active material may be one having a particle size of 50 nm or more and 100 μm or less. 。

[0108] Note that in both the positive electrode active material layer 104 and the negative electrode active material layer 102, a plurality of active material materials may be used in combination at a specific ratio. By using a plurality of materials in the active material layer it is possible to more specifically select the performance of the active material layer.

[0109] As the conductive assistant of the electrode, acetylene black (AB), graphite (carbon) particles, carbon nanotubes, graphene, fullerenes, etc. can be used.

[0110] The conductive assistant can form an electrical conduction network in the electrode. By the conductive assistant it is possible to maintain the electrical conduction path between the negative electrode active materials. By adding a conductive assistant to the negative electrode active material layer, it is possible to realize a negative electrode active material layer 102 having high electrical conductivity.

[0111] In addition, as the binder, in addition to typical polyvinylidene fluoride (PVDF), polyimide , polyvinyl chloride, ethylene propylene diene polymer, styrene-butadiene rubber , acrylonitrile-butadiene rubber, fluororubber, polyvinyl acetate, polymethyl methacrylate , polyethylene, nitrocellulose, etc. can be used.

[0112] The content of the binder with respect to the total amount of the negative electrode active material layer 102 is preferably 1 wt% or more and 10 wt% or less more preferably 2 wt% or more and 8 wt% or less, and still more preferably 3 wt% or more and 5 wt% or less. ​is also preferable. The content of the conductive assistant with respect to the total amount of the negative electrode active material layer 103 is 1 wt% or more and 10 wt% or less is preferable, and 1 wt% or more and 5 wt% or less is more preferable.

[0113] Next, a negative electrode active material layer 102 is formed on the negative electrode current collector 101. When forming the negative electrode active material layer 102 using a coating method, the negative electrode active material, binder, conductive assistant, and dispersion medium are mixed to prepare a slurry, which is applied to the negative electrode current collector 101 and dried. Further, if necessary after drying, a pressing treatment may be performed. When forming the negative electrode active material layer 102 using a coating method, the negative electrode active material, binder, conductive assistant, and dispersion medium are mixed to prepare a slurry, which is applied to the negative electrode current collector 101 and dried. Further, if necessary after drying, a pressing treatment may be performed.

[0114] Note that, as the negative electrode current collector 101, metals such as stainless steel, gold, platinum, iron, copper, titanium, tantalum, and alloys thereof, which have high conductivity and do not alloy with carrier ions such as lithium, can be used. Further, it may be formed of a metal element that reacts with silicon to form a silicide. Examples of the metal element that reacts with silicon to form a silicide include zirconium, titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, nickel, etc. The negative electrode current collector 102 can be appropriately used in shapes such as foil, plate (sheet), net, column, coil, punched metal, expanded metal, etc. The negative electrode current collector 101 is preferably one having a thickness of 5 μm or more and 30 μm or less. Further, an undercoat layer may be provided on a part of the surface of the electrode current collector using graphite or the like. Note that, as the negative electrode current collector 101, metals such as stainless steel, gold, platinum, iron, copper, titanium, tantalum, and alloys thereof, which have high conductivity and do not alloy with carrier ions such as lithium, can be used. Further, it may be formed of a metal element that reacts with silicon to form a silicide. Examples of the metal element that reacts with silicon to form a silicide include zirconium, titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, nickel, etc. Examples of the metal element that reacts with silicon to form a silicide include zirconium, titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, nickel, etc. The negative electrode current collector 102 can be appropriately used in shapes such as foil, plate (sheet), net, column, coil, punched metal, expanded metal, etc. The negative electrode current collector 102 can be appropriately used in shapes such as foil, plate (sheet), net, column, coil, punched metal, expanded metal, etc. The negative electrode current collector 101 is preferably one having a thickness of 5 μm or more and 30 μm or less. Further, an undercoat layer may be provided on a part of the surface of the electrode current collector using graphite or the like.

[0115] Note that a configuration can be adopted in which the negative electrode active material layer 102 is provided on one side of the negative electrode current collector 101 and not provided on the other side. In that case, in a state where the negative electrode active material layer is not provided, ​​​In this case, the surface of the negative electrode current collector 101 is flat and has a small coefficient of friction. Therefore, when a surface of the negative electrode current collector to which the negative electrode active material layer of the other negative electrode current collector is not provided comes into contact, the two current collectors can slide relative to each other according to the stress.

[0116] The negative electrode of the lithium ion battery can be manufactured by the above steps.

[0117] ≪Configuration of Separator≫ The separator 103 will be described. As the material of the separator 103, paper, non-woven fabric, glass fiber, or synthetic fibers such as nylon (polyamide), vinylon (polyvinyl alcohol-based fiber), polyester, acrylic, polyolefin, polyurethane, etc. can be used. However, it is necessary to select a material that does not dissolve in the electrolyte described later.

[0118] More specifically, as the material of the separator 103, for example, a fluorine-based polymer, a polyether such as polyethylene oxide or polypropylene oxide, a polyolefin such as polyethylene or polypropylene, polyacrylonitrile, polyvinylidene chloride, polymethyl methacrylate, polymethyl acrylate, polyvinyl alcohol, polymethacrylonitrile,

[0119] The separator 103 must have insulating performance to prevent contact between the two electrodes, performance to hold the electrolyte, and ion conductivity. As a method for manufacturing a film having the function of a separator, a method of ​ There is a method by stretching. For example, a molten polymer material is spread and heat is dissipated, and the resulting film is stretched in a biaxial direction parallel to the film to form holes, which is called the stretching and perforating method.

[0120] In the above process, the separator can be incorporated into the lithium-ion battery.

[0121] ≪Constitution of Electrolyte≫

[0122] The electrolyte 107 that can be used in the lithium-ion battery according to one aspect of the present invention is preferably a non-aqueous solution (solvent) containing an electrolyte (solute). As the solvent of the electrolyte 107, a material in which carrier ions can move is used. For example, an aprotic organic solvent is preferred, such as ethylene carbonate (EC), propylene carbonate

[0123] (PC), butylene carbonate, chloroethylene carbonate, vinylene carbonate , γ-butyrolactone, γ-valerolactone, dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), methyl formate, methyl acetate , methyl butyrate, 1,3-dioxane, 1,4-dioxane, dimethoxyethane (DM E), dimethyl sulfoxide, diethyl ether, methyl diglyme, acetonitrile, benzonitrile, tetrahydrofuran, sulfolane, sultone, etc., or any combination and ratio of two or more of these can be used. In addition, by using a polymer material that is gelled as the solvent of the electrolyte 107, the safety against liquid leakage and the like is enhanced. Also, the lithium-ion battery can be made thinner and lighter. Gel

[0124] Representative examples of polymeric materials that can be polymerized are silicone gel, acrylic gel, and acrylonitrile. Polyethylene oxide gel, Polypropylene oxide gel, Fluorine-based gel Examples include polymer gels.

[0125] In addition, ionic liquids (also called room temperature molten salts), which are flame-retardant and difficult to evaporate, are used as the solvent for the electrolyte. ) is used to prevent internal short circuits in lithium-ion batteries and overcharging. Even if the internal temperature rises, the lithium-ion battery can be prevented from exploding or catching fire. This can improve the safety of the lithium-ion storage battery.

[0126] In addition, the electrolyte used in the storage battery is free of granular waste and elements other than the constituent elements of the electrolyte (hereinafter simply referred to as It is preferable to use a highly purified electrolyte solution with a low content of "impurities." Specifically, the mass ratio of impurities to the electrolyte is 1% or less, preferably 0.1% or less, more preferably 1% or less. More preferably, the content of vinylene carbonate in the electrolyte is 0.01% or less. Additives such as ethyl acetate may also be added.

[0127] In addition, when lithium ions are used as a carrier, the electrolyte to be dissolved in the above-mentioned solvent is , e.g. LiPF 6 , LiClO 4 , LiAsF 6 , LiBF 4 , LiAlCl 4 , Li SCN, LiBr, LiI, Li 2 SO 4 , Li 2 B 10 Cl 10 , Li 2 B 12 Cl 1 2 , LiCF 3 SO3 , LiC 4 F 9 SO 3 , LiC(CF 3 SO 2 ) 3 , LiC(C 2 F 5 SO 2 ) 3 , LiN(CF 3 SO 2 ) 2 , LiN(C 4 F 9 SO 2 )(CF 3 SO 2 ), LiN(C 2 F 5 SO 2 ) 2 One or more of the following lithium salts can be used in any combination and ratio: They can be used in any combination and ratio.

[0128] In the above electrolyte, the case where the carrier ion is a lithium ion has been described, but carrier ions other than lithium ions can also be used. As carrier ions other than lithium ions, in the case of alkali metal ions or alkaline earth metal ions, as the electrolyte, in the above lithium salts, an alkali metal (e.g., sodium, potassium, etc.) or an alkaline earth metal (e.g., calcium, strontium, barium, beryllium, or magnesium, etc.) can be used instead of lithium.

[0129] Note that the electrolytic solution may react with the current collector of the positive electrode and corrode the positive electrode current collector. To prevent such corrosion, it is preferable to add several wt% of LiPF 6 to the electrolytic solution. This is to form an insulating film on the surface of the positive electrode current collector, and the insulating film suppresses the reaction between the electrolytic solution and the positive electrode current collector. Yes. However, in order not to dissolve the positive electrode active material layer, the concentration of LiPF 6 is 10 wt% or less , preferably 5 wt% or less, more preferably 3 wt% or less.

[0130] ≪Configuration of the exterior body≫ Next, the exterior body 116 will be described. The exterior body 116 is, for example, made of a film composed of materials such as polyethylene, polypropylene , polycarbonate, ionomer, polyamide, etc., and a metal thin film with excellent flexibility such as aluminum , stainless steel, copper, nickel, etc. is provided on the film, and further, an insulating synthetic resin such as a polyamide-based resin or a polyester-based resin is provided as the outer surface of the exterior body on the metal thin film. A three-layer structure film can be used. By adopting such a three-layer structure , the permeation of the electrolytic solution and gas is blocked, insulation is ensured, and at the same time, it has resistance to the electrolytic solution . The exterior body is bent and overlapped inside, or the inner surfaces of the two exterior bodies are faced each other and heat is applied to melt the material on the inner surface and fuse the two exterior bodies, thereby forming a sealing structure. If the part where the exterior body is fused or the like to form a sealing structure is defined as the sealing part, when the exterior body is bent and overlapped inside

[0131] , the sealing part is formed at a location other than the fold, and the first region of the exterior body and the second region overlapping the first region are fused or the like. Also, when two exterior bodies are overlapped , the sealing part is formed on the entire outer periphery by a method such as heat fusion.

[0132] In one aspect of the present invention, the exterior body 116 preferably has a length of a certain value or more in order to provide a void inside the lithium-ion battery 11 0 as described above.

[0133] ≪Flexible battery≫ When a flexible material is selected and used from the materials of each member shown in this embodiment, a flexible lithium-ion battery can be manufactured. In recent years, research and development of deformable devices have been actively carried out. As a battery used for such devices, there is a demand for a battery having flexibility.

[0134] When a battery in which two films are used as an exterior body and sandwich 1805 such as an electrode and an electrolyte is curved, the radius of curvature 1802 of the film 1801 on the side closer to the center of curvature 1800 of the battery is smaller than the radius of curvature 1804 of the film 1803 on the side farther from the center of curvature 1800 (Fig. 7( A)). When the battery is curved so that its cross-section is arc-shaped, compressive stress is applied to the surface of the film closer to the center of curvature 1800, and tensile stress is applied to the surface of the film farther from the center of curvature 1800 (Fig. 7(B)).

[0135] When a flexible lithium-ion battery is deformed, a large stress is applied to the exterior body. However, if a pattern formed by concave or convex portions is formed on the surface of the exterior body, even if compressive stress or tensile stress is applied due to the deformation of the battery, the influence of strain can be suppressed. Therefore, the battery can be deformed within a range where the radius of curvature of the exterior body on the side closer to the center of curvature is preferably 50 mm, more preferably 30 mm.

[0136] The radius of curvature of the surface will be described with reference to Fig. 8. In Fig. 8(A), in the plane 1701 that cuts the curved surface 1700, a part of the curve 1702 included in the curved surface 1700 is approximated to an arc of a circle, the radius of the circle is defined as the radius of curvature 1703, and the center of the circle is defined as the center of curvature 1704. Fig. FIG. 8(B) shows a top view of the curved surface 1700. FIG. 8(C) shows a cross-sectional view of the curved surface 1700 cut by the plane 1701. When cutting a curved surface with a plane, the radius of curvature of the curve appearing in the cross-section varies depending on the angle of the plane with respect to the curved surface and the position of the cut. In this specification, etc., the smallest radius of curvature is taken as the radius of curvature of the surface. When cutting the curved surface with a plane, the radius of curvature of the curve appearing in the cross-section varies depending on the angle of the plane with respect to the curved surface and the position of the cut. However, in this specification, etc., the smallest radius of curvature is taken as the radius of curvature of the surface. Note that the cross-sectional shape of the storage battery is not limited to a simple arc shape, and it can be a shape having a part of an arc, for example, the shape shown in FIG. 7(C), a wavy shape (FIG. 7(D)), an S-shaped shape, etc.

[0137] When the curved surface of the storage battery has a shape having a plurality of curvature centers, among the radii of curvature at each of the plurality of curvature centers, in the curved surface having the smallest radius of curvature, the storage battery can be deformed within a range where the radius of curvature of the outer package closer to the curvature center of the two outer packages is preferably 50 mm, more preferably 30 mm. Note that the cross-sectional shape of the storage battery is not limited to a simple arc shape, and it can be a shape having a part of an arc, for example, the shape shown in FIG. 7(C), a wavy shape (FIG. 7(D)), an S-shaped shape, etc. When the curved surface of the storage battery has a shape having a plurality of curvature centers, among the radii of curvature at each of the plurality of curvature centers, in the curved surface having the smallest radius of curvature, the storage battery can be deformed within a range where the radius of curvature of the outer package closer to the curvature center of the two outer packages is preferably 50 mm, more preferably 30 mm. When the curved surface of the storage battery has a shape having a plurality of curvature centers, among the radii of curvature at each of the plurality of curvature centers, in the curved surface having the smallest radius of curvature, the storage battery can be deformed within a range where the radius of curvature of the outer package closer to the curvature center of the two outer packages is preferably 50 mm, more preferably 30 mm. When the curved surface of the storage battery has a shape having a plurality of curvature centers, among the radii of curvature at each of the plurality of curvature centers, in the curved surface having the smallest radius of curvature, the storage battery can be deformed within a range where the radius of curvature of the outer package closer to the curvature center of the two outer packages is preferably 50 mm, more preferably 30 mm. When the curved surface of the storage battery has a shape having a plurality of curvature centers, among the radii of curvature at each of the plurality of curvature centers, in the curved surface having the smallest radius of curvature, the storage battery can be deformed within a range where the radius of curvature of the outer package closer to the curvature center of the two outer packages is preferably 50 mm, more preferably 30 mm.

[0138] ≪Assembly and Aging of Storage Battery≫ Next, by combining the above-described constituent members and sealing the outer package 207, an internal structure having a plurality of laminates in which the positive electrode current collector 105, the positive electrode active material layer 104, the separator 103, the negative electrode active material layer 102, and the negative electrode current collector 101 are stacked is sealed together with the electrolytic solution 107 by the outer package 107 as shown in FIGS. 1 and 2. Next, by combining the above-described constituent members and sealing the outer package 207, an internal structure having a plurality of laminates in which the positive electrode current collector 105, the positive electrode active material layer 104, the separator 103, the negative electrode active material layer 102, and the negative electrode current collector 101 are stacked is sealed together with the electrolytic solution 107 by the outer package 107 as shown in FIGS. 1 and 2. Next, by combining the above-described constituent members and sealing the outer package 207, an internal structure having a plurality of laminates in which the positive electrode current collector 105, the positive electrode active material layer 104, the separator 103, the negative electrode active material layer 102, and the negative electrode current collector 101 are stacked is sealed together with the electrolytic solution 107 by the outer package 107 as shown in FIGS. 1 and 2. Next, by combining the above-described constituent members and sealing the outer package 207, an internal structure having a plurality of laminates in which the positive electrode current collector 105, the positive electrode active material layer 104, the separator 103, the negative electrode active material layer 102, and the negative electrode current collector 101 are stacked is sealed together with the electrolytic solution 107 by the outer package 107 as shown in FIGS. 1 and 2.

[0139] Next, an aging process is performed. First, the environmental temperature is maintained at about room temperature, and constant current charging is performed at a low rate until a uniform voltage. Next, the gas generated in the region inside the outer package due to charging is discharged to the outside of the outer package. Next, charging is performed at a rate higher than the first charging rate. Next, an aging process is performed. First, the environmental temperature is maintained at about room temperature, and constant current charging is performed at a low rate until a uniform voltage. Next, the gas generated in the region inside the outer package due to charging is discharged to the outside of the outer package. Next, charging is performed at a rate higher than the first charging rate. Next, an aging process is performed. First, the environmental temperature is maintained at about room temperature, and constant current charging is performed at a low rate until a uniform voltage. Next, the gas generated in the region inside the outer package due to charging is discharged to the outside of the outer package. Next, charging is performed at a rate higher than the first charging rate.

[0140] Thereafter, it is stored for a long time in a slightly high temperature environment. For example, it is stored for 24 hours or more in an environment of 40 °C or higher. or more.

[0141] After storing for a long time in a slightly high temperature environment, the gas generated in the region inside the outer package is released again. Furthermore, it is discharged at a rate of 0.2 C in a room temperature environment, charged at the same rate, discharged again at the same rate, and then charged again at the same rate. Then, the charging process is terminated by discharging at the same rate. and the charging process is terminated.

[0142] In the above manner, the storage battery according to the present invention can be manufactured.

[0143] This embodiment can be implemented in appropriate combination with other embodiments.

[0144] In addition, in this specification and the like, when at least one specific example is described in the figure or text described in a certain embodiment, it is easily understood by those skilled in the art to derive the upper concept of the specific example. Therefore, when at least one specific example is described in the figure or text described in a certain embodiment, the upper concept of the specific example is also disclosed as one aspect of the invention and can constitute one aspect of the invention. And it can be said that one aspect of the invention is clear. In addition, in this specification and the like, when at least one specific example is described in the figure or text described in a certain embodiment, the upper concept of the specific example is also disclosed as one aspect of the invention and can constitute one aspect of the invention. And it can be said that one aspect of the invention is clear. And one aspect of the invention can be said to be clear.

[0145] In addition, in this specification and the like, at least the content described in the figure (even a part in the figure) is disclosed as one aspect of the invention and can constitute one aspect of the invention. Therefore, for a certain content, if it is described in the figure, even if it is not described in the text, the content is disclosed as one aspect of the invention and can constitute one aspect of the invention. Therefore, for a certain content, if it is described in the figure, even if it is not described in the text, the content is It is possible to achieve. Similarly, for a figure obtained by extracting a part of a figure, it is also disclosed as one aspect of the invention and can constitute one aspect of the invention. And it can be said that one aspect of the invention is clear. In addition, in this embodiment, one aspect of the present invention has been described. Or, in other embodiments, one aspect of the present invention is described. However, one aspect of the present invention is not limited to these. That is, in this embodiment and other embodiments, various aspects of the invention are described, so one aspect of the present invention is not limited to a specific aspect. For example, as one aspect of the present invention, an example when applied to a flexible lithium-ion secondary battery is shown, but one aspect of the present invention is not limited to this. Depending on the case or situation, one aspect of the present invention may be applied to various secondary batteries, lead-acid batteries, lithium-ion polymer secondary batteries, nickel-metal hydride

[0146] batteries, nickel-cadmium batteries, nickel-iron batteries, nickel-zinc batteries, silver-zinc oxide batteries, solid-state batteries, air batteries, primary batteries, capacitors, or electric double-layer capacitors, ultra-capacitors, super-capacitors, lithium-ion capacitors, etc. Or, for example, depending on the case or situation, one aspect of the present invention does not have to be applied to a lithium-ion secondary battery. In this embodiment, the structure of a storage battery according to one aspect of the present invention will be described with reference to FIGS. 9 to 11. <<Coin-type storage battery>> FIG. 9(A) is an external view of a coin-type (single-layer flat type) storage battery, and FIG. 9(B) is a cross-sectional view thereof. batteries, nickel-cadmium batteries, nickel-iron batteries, nickel-zinc batteries, silver-zinc oxide batteries, solid-state batteries, air batteries, primary batteries, capacitors, or electric double-layer capacitors, ultra-capacitors, super-capacitors, lithium-ion capacitors, etc. Or, for example, depending on the case or situation, one aspect of the present invention does not have to be applied to a lithium-ion secondary battery. FIG. 9(A) is an external view of a coin-type (single-layer flat type) storage battery, and FIG. 9(B) is a cross-sectional view thereof.

[0147] (Embodiment 2) In this embodiment, the structure of a storage battery according to one aspect of the present invention will be described with reference to FIGS. 9 to 11. <<Coin-type storage battery>>

[0148] <<Coin-type storage battery>> FIG. 9(A) is an external view of a coin-type (single-layer flat type) storage battery, and FIG. 9(B) is a cross-sectional view thereof. It is a top view.

[0149] The coin-shaped storage battery 300 has a positive electrode can 301 that also serves as a positive electrode terminal and a negative electrode can 3 02 that also serves as a negative electrode terminal, which are insulated and sealed with a gasket 303 made of polypropylene or the like. The positive electrode 304 is formed by a positive electrode current collector 305 and a positive electrode active material layer 306 provided in contact therewith. The positive electrode active material layer 306 may, in addition to the positive electrode active material, have a binder for enhancing the adhesion of the positive electrode active material, a conductive assistant for enhancing the conductivity of the positive electrode active material layer, and the like.

[0150] Further, the negative electrode 307 is formed by a negative electrode current collector 308 and a negative electrode active material layer 309 provided in contact therewith. The negative electrode active material layer 309 may, in addition to the negative electrode active material, have a binder for enhancing the adhesion of the negative electrode active material, a conductive assistant for enhancing the conductivity of the negative electrode active material layer, and the like. Between the positive electrode active material layer 306 and the negative electrode active material layer 309, there are a separator 31 0 and an electrolyte (not shown).

[0151] For each component, the materials shown in Embodiment 1 can be used.

[0152] For the positive electrode can 301 and the negative electrode can 302, metals such as nickel and titanium that are corrosion-resistant to the electrolytic solution, or alloys thereof or alloys of these with other metals (for example, stainless steel, etc.) can be used. Also, in order to prevent corrosion by the electrolytic solution, it is preferable to coat with nickel or the like. The positive electrode can 301 is electrically connected to the positive electrode 304, and the negative electrode can 302 is electrically connected to the negative electrode 307, respectively.

[0153] These negative electrode 307, positive electrode 304, and separator 310 are impregnated with the electrolyte, as shown in FIG. 9(B). As shown, with the positive electrode can 301 facing downwards, the positive electrode 304, separator 310, negative electrode 307, and negative electrode can 302 are stacked in this order, and the positive electrode can 301 and the negative electrode can 302 are pressure-bonded via a gasket 303 to manufacture a coin-shaped storage battery 300.

[0154] Here, the flow of current during charging of the storage battery will be described with reference to FIG. 9(C). When a lithium-based storage battery is regarded as a single closed circuit, the movement of lithium ions and the flow of current are in the same direction. . In a lithium-based storage battery, during charging and discharging, the anode (positive electrode) and cathode (negative electrode ) are interchanged, and the oxidation reaction and reduction reaction are interchanged. Therefore, the electrode with a higher reaction potential is called the positive electrode, and the electrode with a lower reaction potential is called the negative electrode. Therefore, in this specification, whether during charging, discharging, or when a reverse pulse current is flowing, or when a charging current is flowing, the positive electrode is called the "positive electrode" or the "+ electrode (plus electrode)", and the negative electrode is called the "negative electrode " or the "- electrode (minus electrode)". When using terms related to the oxidation reaction or reduction reaction such as anode (positive electrode) and cathode (negative electrode), it will be reversed during charging and discharging, which may cause confusion. Therefore, the terms anode (positive electrode) and cathode (negative electrode ) will not be used in this specification. If the terms anode (positive electrode) and cathode (negative electrode ) are used, it is necessary to specify whether it is during charging or discharging, and also to indicate which corresponds to the positive electrode (plus electrode ) and which corresponds to the negative electrode (minus electrode).

[0155] A charger is connected to the two terminals shown in FIG. 9(C), and the storage battery 400 is charged. As the charging of the storage battery 400 progresses, the potential difference between the electrodes increases. In FIG. 9(C), for the storage battery 400 Flowing from the external terminal towards the positive electrode 402, within the storage battery 400, the direction of the current flowing from the positive electrode 402 towards the negative electrode 404 and then flowing from the negative electrode towards the external terminal of the storage battery 400 is defined as the positive direction. That is, the direction in which the charging current flows is defined as the direction of the current.

[0156] ≪Cylindrical Storage Battery≫ Next, an example of a cylindrical storage battery will be described with reference to FIG. 10. As shown in FIG. 10(A), the cylindrical storage battery 60 0 has a positive electrode cap (battery cover) 601 on its upper surface and a battery can (outer can) 602 on its side surface and bottom surface. These positive electrode cap and battery can (outer can) 6 02 are insulated from each other by a gasket (insulating packing) 610.

[0157] FIG. 10(B) is a diagram schematically showing a cross-section of the cylindrical storage battery. Inside the hollow cylindrical battery can 602, a battery element is provided in which a strip-shaped positive electrode 604 and a negative electrode 606 are wound with a separator 605 in between. Although not shown, the battery element is wound around a center pin. One end of the battery can 602 is closed and the other end is open. For the battery can 602, metals such as nickel and titanium that are corrosion-resistant to the electrolytic solution, or alloys of these or alloys of these with other metals (e.g., stainless steel, etc.) can be used. Also, in order to prevent corrosion by the electrolytic solution, it is preferable to coat with nickel or the like. Inside the battery can 602, the battery element in which the positive electrode, negative electrode, and separator are wound is sandwiched between a pair of opposing insulating plates 608, 609. Further, the inside of the battery can 602 where the battery element is provided is filled with a non-aqueous electrolyte solution (not shown). The non-aqueous electrolyte solution can be the same as that of the coin-type storage battery.

[0158] ​​​​ The positive electrode 604 and the negative electrode 606 may be manufactured in the same manner as the positive and negative electrodes of the coin-type storage battery described above. However, since the positive and negative electrodes used in the cylindrical storage battery are wound, they are different in that the active material is formed on both sides of the current collector. A positive electrode terminal (positive current collector tab) 603 is connected to the positive electrode 604, and a negative electrode terminal (negative current collector tab) 607 is connected to the negative electrode 606. Both the positive electrode terminal 603 and the negative electrode terminal 607 can use a metal material such as aluminum. The positive electrode terminal 603 is resistance welded to the safety valve mechanism 612, and the negative electrode terminal 607 is resistance welded to the bottom of the battery can 602. The safety valve mechanism 612 is electrically connected to the positive electrode cap 601 via a PTC element (Positive Temperature Coefficient) 611. When the internal pressure of the battery rises beyond a predetermined threshold value, the safety valve mechanism 612 disconnects the electrical connection between the positive electrode cap 601 and the positive electrode 604. The PTC element 611 is a thermal resistance element whose resistance increases when the temperature rises. By increasing the resistance, the current amount is limited to prevent abnormal heat generation. For the PTC element, barium titanate (BaTiO) - based semiconductor ceramics or the like can be used. ... ... ... ... ... ... ... ... ... ... ... 3 ...

[0159] ≪Laminated Battery≫ Next, an example of a laminated battery will be described with reference to Fig. 11(A). If the laminated battery has a flexible configuration, when it is mounted on an electronic device having at least a part of a flexible portion, the battery can also be bent in accordance with the deformation of the electronic device. ... ...

[0160] The laminated battery 500 shown in Fig. 11(A) includes a positive current collector 501 and a positive active material The positive electrode 503 having layer 502, the negative electrode 506 having the negative electrode current collector 504 and the negative electrode active material layer 505, the separator 507, the electrolytic solution 508, and the exterior body 509. A separator 507 is installed between the positive electrode 503 and the negative electrode 506 provided in the exterior body 509. Also, the inside of the exterior body 509 is filled with the electrolytic solution 508. As the electrolytic solution 508, the electrolytic solution shown in Embodiment Form 1 can be used. In the laminated battery 500 shown in Fig. 11(A), the positive electrode current collector 501 and the negative electrode current collector 504 also serve as terminals for obtaining electrical contact with the outside. Therefore, a part of the positive electrode current collector 501 and the negative electrode current collector 504 may be arranged to be exposed to the outside from the exterior body 509. Also, instead of exposing the positive electrode current collector 501 and the negative electrode current collector 504 to the outside from the exterior body 509, a tab electrode may be ultrasonically bonded to the tab electrode and the positive electrode current collector 501 or the negative electrode current collector 504 so that the tab electrode is exposed to the outside. In the laminated battery 500 shown in Fig. 11(A), the positive electrode current collector 501 and the negative electrode current collector 504 also serve as terminals for obtaining electrical contact with the outside. Therefore, a part of the positive electrode current collector 501 and the negative electrode current collector 504 may be arranged to be exposed to the outside from the exterior body 509. Also, instead of exposing the positive electrode current collector 501 and the negative electrode current collector 504 to the outside from the exterior body 509, a tab electrode may be ultrasonically bonded to the tab electrode and the positive electrode current collector 501 or the negative electrode current collector 504 so that the tab electrode is exposed to the outside. In the laminated battery 500 shown in Fig. 11(A), the positive electrode current collector 501 and the negative electrode current collector 504 also serve as terminals for obtaining electrical contact with the outside. Therefore, a part of the positive electrode current collector 501 and the negative electrode current collector 504 may be arranged to be exposed to the outside from the exterior body 509. Also, instead of exposing the positive electrode current collector 501 and the negative electrode current collector 504 to the outside from the exterior body 509, a tab electrode may be ultrasonically bonded to the tab electrode and the positive electrode current collector 501 or the negative electrode current collector 504 so that the tab electrode is exposed to the outside. In the laminated battery 500 shown in Fig. 11(A), the positive electrode current collector 501 and the negative electrode current collector 504 also serve as terminals for obtaining electrical contact with the outside. Therefore, a part of the positive electrode current collector 501 and the negative electrode current collector 504 may be arranged to be exposed to the outside from the exterior body 509. Also, instead of exposing the positive electrode current collector 501 and the negative electrode current collector 504 to the outside from the exterior body 509, a tab electrode may be ultrasonically bonded to the tab electrode and the positive electrode current collector 501 or the negative electrode current collector 504 so that the tab electrode is exposed to the outside.

[0161] In the laminated battery 500 shown in Fig. 11(A), the positive electrode current collector 501 and the negative electrode current collector 504 also serve as terminals for obtaining electrical contact with the outside. Therefore, a part of the positive electrode current collector 501 and the negative electrode current collector 504 may be arranged to be exposed to the outside from the exterior body 509. Also, instead of exposing the positive electrode current collector 501 and the negative electrode current collector 504 to the outside from the exterior body 509, a tab electrode may be ultrasonically bonded to the tab electrode and the positive electrode current collector 501 or the negative electrode current collector 504 so that the tab electrode is exposed to the outside. In the laminated battery 500 shown in Fig. 11(A), the positive electrode current collector 501 and the negative electrode current collector 504 also serve as terminals for obtaining electrical contact with the outside. Therefore, a part of the positive electrode current collector 501 and the negative electrode current collector 504 may be arranged to be exposed to the outside from the exterior body 509. Also, instead of exposing the positive electrode current collector 501 and the negative electrode current collector 504 to the outside from the exterior body 509, a tab electrode may be ultrasonically bonded to the tab electrode and the positive electrode current collector 501 or the negative electrode current collector 504 so that the tab electrode is exposed to the outside. In the laminated battery 500 shown in Fig. 11(A), the positive electrode current collector 501 and the negative electrode current collector 504 also serve as terminals for obtaining electrical contact with the outside. Therefore, a part of the positive electrode current collector 501 and the negative electrode current collector 504 may be arranged to be exposed to the outside from the exterior body 509. Also, instead of exposing the positive electrode current collector 501 and the negative electrode current collector 504 to the outside from the exterior body 509, a tab electrode may be ultrasonically bonded to the tab electrode and the positive electrode current collector 501 or the negative electrode current collector 504 so that the tab electrode is exposed to the outside. In the laminated battery 500 shown in Fig. 11(A), the positive electrode current collector 501 and the negative electrode current collector 504 also serve as terminals for obtaining electrical contact with the outside. Therefore, a part of the positive electrode current collector 501 and the negative electrode current collector 504 may be arranged to be exposed to the outside from the exterior body 509. Also, instead of exposing the positive electrode current collector 501 and the negative electrode current collector 504 to the outside from the exterior body 509, a tab electrode may be ultrasonically bonded to the tab electrode and the positive electrode current collector 501 or the negative electrode current collector 504 so that the tab electrode is exposed to the outside. In the laminated battery 500 shown in Fig. 11(A), the positive electrode current collector 501 and the negative electrode current collector 504 also serve as terminals for obtaining electrical contact with the outside. Therefore, a part of the positive electrode current collector 501 and the negative electrode current collector 504 may be arranged to be exposed to the outside from the exterior body 509. Also, instead of exposing the positive electrode current collector 501 and the negative electrode current collector 504 to the outside from the exterior body 509, a tab electrode may be ultrasonically bonded to the tab electrode and the positive electrode current collector 501 or the negative electrode current collector 504 so that the tab electrode is exposed to the outside. In the laminated battery 500 shown in Fig. 11(A), the positive electrode current collector 501 and the negative electrode current collector 504 also serve as terminals for obtaining electrical contact with the outside. Therefore, a part of the positive electrode current collector 501 and the negative electrode current collector 504 may be arranged to be exposed to the outside from the exterior body 509. Also, instead of exposing the positive electrode current collector 501 and the negative electrode current collector 504 to the outside from the exterior body 509, a tab electrode may be ultrasonically bonded to the tab electrode and the positive electrode current collector 501 or the negative electrode current collector 504 so that the tab electrode is exposed to the outside.

[0162] In the laminated battery 500, for the exterior body 509, a three-layer laminated film can be used in which a flexible metal thin film made of a material such as aluminum, stainless steel, copper, nickel, etc. is provided on a film made of a material such as polyethylene, polypropylene, polycarbonate, ionomer, polyamide, etc., and an insulating synthetic resin film such as a polyamide-based resin or a polyester-based resin is provided as the outer surface of the exterior body on the metal thin film. In the laminated battery 500, for the exterior body 509, a three-layer laminated film can be used in which a flexible metal thin film made of a material such as aluminum, stainless steel, copper, nickel, etc. is provided on a film made of a material such as polyethylene, polypropylene, polycarbonate, ionomer, polyamide, etc., and an insulating synthetic resin film such as a polyamide-based resin or a polyester-based resin is provided as the outer surface of the exterior body on the metal thin film. In the laminated battery 500, for the exterior body 509, a three-layer laminated film can be used in which a flexible metal thin film made of a material such as aluminum, stainless steel, copper, nickel, etc. is provided on a film made of a material such as polyethylene, polypropylene, polycarbonate, ionomer, polyamide, etc., and an insulating synthetic resin film such as a polyamide-based resin or a polyester-based resin is provided as the outer surface of the exterior body on the metal thin film. In the laminated battery 500, for the exterior body 509, a three-layer laminated film can be used in which a flexible metal thin film made of a material such as aluminum, stainless steel, copper, nickel, etc. is provided on a film made of a material such as polyethylene, polypropylene, polycarbonate, ionomer, polyamide, etc., and an insulating synthetic resin film such as a polyamide-based resin or a polyester-based resin is provided as the outer surface of the exterior body on the metal thin film. In the laminated battery 500, for the exterior body 509, a three-layer laminated film can be used in which a flexible metal thin film made of a material such as aluminum, stainless steel, copper, nickel, etc. is provided on a film made of a material such as polyethylene, polypropylene, polycarbonate, ionomer, polyamide, etc., and an insulating synthetic resin film such as a polyamide-based resin or a polyester-based resin is provided as the outer surface of the exterior body on the metal thin film.

[0163] Also, an example of the cross-sectional structure of the laminated battery 500 is shown in Fig. 11(B). In Fig. 11(A), for simplicity, an example of being composed of two current collectors is shown, but actually, it is composed of a plurality of electrode layers. In Fig. 11(A), for simplicity, an example of being composed of two current collectors is shown, but actually, it is composed of a plurality of electrode layers. Configure.

[0164] In FIG. 11B, as an example, the number of electrode layers is 16. In FIG. 11B, the negative electrode current collector 504 has eight layers, and the positive electrode current collector 504 has eight layers. The electrode current collector 501 has a structure of 8 layers, totaling 16 layers. The cross section of the protruding portion is shown, and eight layers of negative electrode current collector 504 are ultrasonically bonded. The number of electrode layers is not limited to 16, and may be more or less. In addition, when the number of electrode layers is small, the capacity of the battery can be increased. This allows the storage battery to be made thin and has excellent flexibility.

[0165] An example of the external appearance of a laminated type storage battery 500 is shown in FIGS. 12 and 13. 13 shows a positive electrode 503, a negative electrode 506, a separator 507, an outer casing 509, and a positive electrode tab electrode. It has a positive electrode 510 and a negative electrode tab electrode 511.

[0166] FIG. 14A shows an external view of a positive electrode 503 and a negative electrode 506. The positive electrode 503 is connected to a positive electrode current collector 50 1, and the positive electrode active material layer 502 is formed on the surface of the positive electrode current collector 501. The positive electrode current collector 503 has a region (called a tab region) where the positive electrode current collector 501 is partially exposed. The negative electrode has a negative electrode current collector 504, and a negative electrode active material layer 505 is formed on the surface of the negative electrode current collector 504. The negative electrode 506 has a region where the negative electrode current collector 504 is partially exposed, i.e., a tab region. The area and shape of the tab regions of the positive and negative electrodes are not limited to the example shown in FIG. stomach.

[0167] <How to make a laminated battery> Here, an example of a method for manufacturing a laminated battery, the external view of which is shown in FIG. 12, will be described with reference to FIGS. 14( B) and (C).

[0168] First, the negative electrode 506, the separator 507, and the positive electrode 503 are laminated. FIG. 14(B) shows the laminated negative electrode 506, separator 507, and positive electrode 503. Here, an example in which five sets of negative electrodes and four sets of positive electrodes are used is shown. Next, the tabs of the positive electrode 503 are joined together, and the positive tab electrode 510 is joined to the tab region of the outermost positive electrode. For the joining, for example, ultrasonic welding or the like can be used. Similarly, the tabs of the negative electrode 506 are joined together, and the negative tab electrode 511 is joined to the tab region of the outermost negative electrode.

[0169] Next, the negative electrode 506, the separator 507, and the positive electrode 503 are arranged on the exterior body 509.

[0170] Next, as shown in FIG. 14(C), the exterior body 509 is bent at the portion indicated by the dashed line. Then, the outer periphery of the exterior body 509 is joined. For the joining, for example, thermocompression bonding or the like can be used. At this time so that the electrolytic solution 508 can be introduced later, a region (hereinafter referred to as the inlet) that is not joined is provided in a part (or one side) of the exterior body 509.

[0171] Next, the electrolytic solution 508 is introduced into the interior of the exterior body 509 through the inlet provided in the exterior body 509. The introduction of the electrolytic solution 508 is preferably carried out under a reduced-pressure atmosphere or an inert gas atmosphere. And finally, the inlet is joined. In this way, the battery 500, which is a laminated battery, can be manufactured.

[0172] In this embodiment, as the battery, coin-type, laminated-type, and cylindrical batteries are ​Although shown, variously shaped storage batteries such as other sealed storage batteries and rectangular storage batteries can be used. In addition, a structure in which a plurality of positive electrodes, negative electrodes, and separators are stacked, or a structure in which a positive electrode, a negative electrode, and a separator are wound may be used.

[0173] An example of mounting a flexible laminate type storage battery on an electronic device is shown in FIG. 10. As an electronic device to which a storage battery having a flexible shape is applied, for example, a television set (also referred to as a TV or a television receiver), a monitor for a computer, a digital camera, a digital video camera, a digital photo frame, a mobile phone (also referred to as a mobile phone or a mobile phone device), a portable game machine, a portable information terminal, an audio reproduction device, a pachinko machine, etc. large game machines and the like can be mentioned.

[0174] In addition, it is also possible to incorporate a storage battery having a flexible shape along the inner wall or outer wall of a house or building, or the curved surface of the interior or exterior of an automobile.

[0175] FIG. 15(A) shows an example of a mobile phone. The mobile phone 7400 includes a display unit 7402 incorporated in a housing 7401 , as well as operation buttons 7403, an external connection port 7404, a speaker 7405, a microphone 7406, and the like. Note that the mobile phone 7400 has a storage battery 7407.

[0176] FIG. 15(B) shows a state in which the mobile phone 7400 is bent. When the mobile phone 740 0 is deformed by an external force and the whole is bent, the storage battery 7 407 provided inside it is also bent. Also, at that time, the state of the bent storage battery 7407 is shown in FIG. 15(C). The storage battery 7407 is a laminate type storage battery.​​​​​

[0177] Figure 15(D) shows an example of a bangle-type display device. The portable display device 7100 includes a housing 7101, a display unit 7102, operation buttons 7103, and a storage battery 7104. Also, Figure 15(E) shows the state of the storage battery 7104 bent.

[0178] ≪Structural Example of Storage Battery≫ The structural example of the storage battery will be described with reference to FIGS. 16 to 20.

[0179] FIGS. 16(A) and 16(B) are diagrams showing the external views of the storage battery. The storage battery has a circuit board 900 and a storage battery 913. A label 910 is attached to the storage battery 913. Furthermore, as shown in FIG. 16(B), the storage battery has a terminal 951, a terminal 952, and an antenna 915.

[0180] The circuit board 900 has a terminal 911 and a circuit 912. The terminal 911 is connected to the terminal 951, the terminal 952, the antenna 914, the antenna 915, and the circuit 912. Note that a plurality of terminals 911 may be provided, and each of the plurality of terminals 911 may be used as a control signal input terminal, a power supply terminal, etc.

[0181] The circuit 912 may be provided on the back surface of the circuit board 900. Note that the antennas 914 and 915 are not limited to a coil shape, and may be, for example, linear or plate-shaped. Also, a planar antenna, an aperture antenna, a traveling wave antenna, an EH antenna, a magnetic field antenna, a dielectric antenna, or the like may be used. Alternatively, the antenna 914 or the antenna 915 may be a flat plate-shaped conductor. This flat plate-shaped conductor functions as one of the conductors for electric field coupling. It is possible. That is, as one of the two conductors of the capacitor, the antenna 914 or the antenna 915 may be made to function. Thereby, power can be exchanged not only by an electromagnetic field and a magnetic field but also by an electric field. The line width of the antenna 914 is preferably larger than the line width of the antenna 915. Thereby, the amount of power received by the antenna 914 can be increased. The storage battery has a layer 916 between the antennas 914 and 915 and the storage battery 913. The layer 916 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field. As the layer 916, for example, a magnetic material can be used.

[0182] The line width of the antenna 914 is preferably larger than the line width of the antenna 915. Thereby, the amount of power received by the antenna 914 can be increased. The storage battery has a layer 916 between the antennas 914 and 915 and the storage battery 913. The layer 916 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field. As the layer 916, for example, a magnetic material can be used.

[0183] The storage battery has a layer 916 between the antennas 914 and 915 and the storage battery 913. The layer 916 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field. As the layer 916, for example, a magnetic material can be used. The line width of the antenna 914 is preferably larger than the line width of the antenna 915. Thereby, the amount of power received by the antenna 914 can be increased. The storage battery has a layer 916 between the antennas 914 and 915 and the storage battery 913. The layer 916 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field. As the layer 916, for example, a magnetic material can be used.

[0184] Note that the structure of the storage battery is not limited to that shown in FIG. 16.

[0185] For example, as shown in FIGS. 17(A-1) and 17(A-2), antennas may be provided on each of a pair of opposing surfaces of the storage battery 913 shown in FIGS. 16(A) and 16(B). FIG. 17(A-1) is an external view seen from one side direction of the pair of surfaces, and FIG. 17(A-2) is an external view seen from the other side direction of the pair of surfaces. Note that, for the same parts as the storage battery shown in FIGS. 16(A) and 16(B), the description of the storage battery shown in FIGS. 16(A) and 16(B) can be appropriately cited. As shown in FIG. 17(A-1), the antenna 914 is provided with the layer 916 sandwiched between one of the pair of surfaces of the storage battery 913, and as shown in FIG. 17(A-2), the antenna 915 is provided with the layer 917 sandwiched between the other of the pair of surfaces of the storage battery 913. The layer 917 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field. As shown in FIG. 17(A-1), the antenna 914 is provided with the layer 916 sandwiched between one of the pair of surfaces of the storage battery 913, and as shown in FIG. 17(A-2), the antenna 915 is provided with the layer 917 sandwiched between the other of the pair of surfaces of the storage battery 913. The layer 917 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field. As shown in FIG. 17(A-1), the antenna 914 is provided with the layer 916 sandwiched between one of the pair of surfaces of the storage battery 913, and as shown in FIG. 17(A-2), the antenna 915 is provided with the layer 917 sandwiched between the other of the pair of surfaces of the storage battery 913. The layer 917 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field. As shown in FIG. 17(A-1), the antenna 914 is provided with the layer 916 sandwiched between one of the pair of surfaces of the storage battery 913, and as shown in FIG. 17(A-2), the antenna 915 is provided with the layer 917 sandwiched between the other of the pair of surfaces of the storage battery 913. The layer 917 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field. As shown in FIG. 17(A-1), the antenna 914 is provided with the layer 916 sandwiched between one of the pair of surfaces of the storage battery 913, and as shown in FIG. 17(A-2), the antenna 915 is provided with the layer 917 sandwiched between the other of the pair of surfaces of the storage battery 913. The layer 917 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field.

[0186] As shown in FIG. 17(A-1), the antenna 914 is provided with the layer 916 sandwiched between one of the pair of surfaces of the storage battery 913, and as shown in FIG. 17(A-2), the antenna 915 is provided with the layer 917 sandwiched between the other of the pair of surfaces of the storage battery 913. The layer 917 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field. As shown in FIG. 17(A-1), the antenna 914 is provided with the layer 916 sandwiched between one of the pair of surfaces of the storage battery 913, and as shown in FIG. 17(A-2), the antenna 915 is provided with the layer 917 sandwiched between the other of the pair of surfaces of the storage battery 913. The layer 917 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field. As shown in FIG. 17(A-1), the antenna 914 is provided with the layer 916 sandwiched between one of the pair of surfaces of the storage battery 913, and as shown in FIG. 17(A-2), the antenna 915 is provided with the layer 917 sandwiched between the other of the pair of surfaces of the storage battery 913. The layer 917 has a function of, for example, preventing the influence of the storage battery 913 on the electromagnetic field. It has a function that can prevent the influence on the electromagnetic field. As the layer 917, for example, a magnetic body can be used.

[0187] By adopting the above structure, the sizes of both the antenna 914 and the antenna 915 can be increased to be.

[0188] Alternatively, as shown in FIGS. 17(B-1) and 17(B-2), another antenna may be provided on each of a pair of opposing surfaces of the storage battery 913 shown in FIGS. 16(A) and 16( B). FIG. 17(B-1) is an external view seen from one side direction of the pair of surfaces, and FIG. 17( B-2) is an external view seen from the other side direction of the pair of surfaces. Note that, for the same parts as the storage battery shown in FIGS. 16(A) and 16(B), the description of the storage battery shown in FIGS. 17(A) and 17(B) can be appropriately incorporated. As shown in FIG. 17(B-1), the antennas 914 and 915 are provided with the layer 916 sandwiched between one of a pair of surfaces of the storage battery 913, and as shown in FIG. 17(B-2), the antenna 918 is provided with the layer 917 sandwiched between the other of a pair of surfaces of the storage battery 91 3. The antenna 918 has a function that can, for example, perform data communication with an external device. For the antenna 918,

[0189] for example, an antenna having a shape applicable to the antennas 914 and 915 can be applied. As the communication method between the storage battery and other devices via the antenna 918, for example, NFC or other response methods that can be used between the storage battery and other devices can be applied. As the communication method between the storage battery and other devices via the antenna 918, for example, NFC or other response methods that can be used between the storage battery and other devices can be applied. or other response methods that can be used between the storage battery and other devices can be applied. or other response methods that can be used between the storage battery and other devices can be applied.

[0190] Alternatively, as shown in FIG. 18(A), on the storage battery 913 shown in FIGS. 16(A) and 16(B), ​A display device 920 may be provided. The display device 920 is electrically connected to the terminal 911 via the terminal 919. Note that a label 910 may not be provided at the portion where the display device 920 is provided. For the same portions as the storage batteries shown in FIGS. 16(A) and 16(B), the descriptions of the storage batteries shown in FIGS. 16(A) and 16(B) can be appropriately incorporated. The display device 920 may display, for example, an image indicating whether charging is in progress, an image indicating the stored power amount, etc. As the display device 920, for example, an electronic paper, a liquid crystal display device, an electroluminescence (EL) display device, etc. can be used. For example, by using an electronic paper, the power consumption of the display device 920 can be reduced. Or, as shown in FIG. 18(B), a sensor 921 may be provided in the storage battery 913 shown in FIGS. 16(A) and 16(B). The sensor 921 is electrically connected to the terminal 911 via the terminal 922. For the same portions as the storage batteries shown in FIGS. 16(A) and 16(B), the descriptions of the storage batteries shown in FIGS. 16(A) and 16(B) can be appropriately incorporated. As the sensor 921, for example, it may have a function capable of measuring displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays. By providing the sensor 921, for example, data indicating the environment where the storage battery is placed (such as temperature) can be detected and stored in the memory in the circuit 912.

[0191]

[0192]

[0193]

[0194] Furthermore, a structural example of the storage battery 913 will be described with reference to FIGS. 19 and 20.

[0195] The storage battery 913 shown in FIG. 19(A) has a wound body 950 provided with a terminal 951 and a terminal 952 inside a housing 930. The wound body 950 is impregnated with an electrolytic solution inside the housing 930. The terminal 952 is in contact with the housing 930, and the terminal 951 is not in contact with the housing 930 by using an insulating material or the like. In FIG. 19(A), for the sake of convenience, the housing 930 is shown separately. However, in reality, the wound body 950 is covered by the housing 930, and the terminals 951 and 952 extend outside the housing 930. As the housing 930, a metal material or a resin material can be used.

[0196] As shown in FIG. 19(B), the housing 930 shown in FIG. 19(A) may be formed of a plurality of materials. For example, the storage battery 913 shown in FIG. 19(B) has a housing 930a and a housing 930b bonded together, and a wound body 950 is provided in a region surrounded by the housing 930a and the housing 930b.

[0197] As the housing 930a, an insulating material such as an organic resin can be used. In particular, by using a material such as an organic resin on the surface where the antenna is formed, shielding of the electric field by the storage battery 913 can be suppressed. If the shielding of the electric field by the housing 930a is small, an antenna such as an antenna 914 or an antenna 915 may be provided inside the housing 930a. As the housing 930b, for example, a metal material can be used.

[0198] Furthermore, the structure of the wound body 950 is shown in FIG. 20. The wound body 950 includes a negative electrode 931 and a positive ​​​​​​​​​​It has a negative electrode 931 and a separator 933. The wound body 950 sandwiches the separator 933, and the negative electrode 931 and the positive electrode 932 overlap and are laminated, and the laminated sheet is wound to form a wound body That is. In addition, the lamination of the negative electrode 931, the positive electrode 932, and the separator 933 may be further stacked multiple times.

[0199] The negative electrode 931 is connected to the terminal 911 shown in FIG. 16 via one of the terminals 951 and 952 The positive electrode 932 is connected to the terminal 91 shown in FIG. 16 via the other of the terminals 951 and 952.

[0200] <<Example of an electronic device: Example of mounting on a vehicle>> Next, an example of mounting a storage battery on a vehicle will be shown. When a storage battery is mounted on a vehicle, a next-generation clean energy vehicle such as a hybrid electric vehicle (HEV), an electric vehicle (EV), or a plug-in hybrid vehicle (PHEV) can be realized.

[0201] In FIG. 16, a vehicle using one aspect of the present invention is illustrated. The automobile 8 100 shown in FIG. 21(A) is an electric vehicle that uses an electric motor as a power source for running. Or, a hybrid vehicle that can appropriately select and use an electric motor and an engine as power sources for running. By using one aspect of the present invention, a vehicle that can be repeatedly charged and discharged can be realized. In addition, the automobile 8100 has a storage battery. The storage battery not only drives the electric motor, but can also supply power to lighting devices such as a headlight 8101 and a room light (not shown).

[0202] In addition, the storage battery can power display devices such as a speedometer and a tachometer that the automobile 8100 has. It is possible to supply power to the device. Further, the storage battery can supply power to semiconductor devices such as the navigation system of the automobile 8100. It can supply power to semiconductor devices such as the navigation system of the automobile 8100.

[0203] The automobile 8100 shown in Fig. 21(B) can be charged by receiving power supply from an external charging facility by a plug-in method or a non-contact power supply method or the like to the storage battery of the automobile 8100. It can be charged by receiving power supply from an external charging facility by a plug-in method or a non-contact power supply method or the like. Fig. 21(B) shows a state in which charging is being performed from a ground-mounted charging device 8021 to a storage battery mounted on the automobile 8100 via a cable 8022. When charging, the charging method, the standard of the connector, etc. may be appropriately performed in a predetermined manner. The charging device 8021 may be a charging station provided in a commercial facility or may be a household power source. For example, by the plug-in technology, the storage battery 8024 mounted on the automobile 8100 can be charged by external power supply. Charging can be performed by converting AC power into DC power via a conversion device such as an AC-DC converter. When charging, the charging method, the standard of the connector, etc. may be appropriately performed in a predetermined manner. The charging device 8021 may be a charging station provided in a commercial facility or may be a household power source. For example, by the plug-in technology, the storage battery 8024 mounted on the automobile 8100 can be charged by external power supply. Charging can be performed by converting AC power into DC power via a conversion device such as an AC-DC converter. When charging, the charging method, the standard of the connector, etc. may be appropriately performed in a predetermined manner. The charging device 8021 may be a charging station provided in a commercial facility or may be a household power source. For example, by the plug-in technology, the storage battery 8024 mounted on the automobile 8100 can be charged by external power supply. Charging can be performed by converting AC power into DC power via a conversion device such as an AC-DC converter. When charging, the charging method, the standard of the connector, etc. may be appropriately performed in a predetermined manner. The charging device 8021 may be a charging station provided in a commercial facility or may be a household power source. For example, by the plug-in technology, the storage battery 8024 mounted on the automobile 8100 can be charged by external power supply. Charging can be performed by converting AC power into DC power via a conversion device such as an AC-DC converter. When charging, the charging method, the standard of the connector, etc. may be appropriately performed in a predetermined manner. The charging device 8021 may be a charging station provided in a commercial facility or may be a household power source. For example, by the plug-in technology, the storage battery 8024 mounted on the automobile 8100 can be charged by external power supply. Charging can be performed by converting AC power into DC power via a conversion device such as an AC-DC converter. When charging, the charging method, the standard of the connector, etc. may be appropriately performed in a predetermined manner. The charging device 8021 may be a charging station provided in a commercial facility or may be a household power source. For example, by the plug-in technology, the storage battery 8024 mounted on the automobile 8100 can be charged by external power supply. Charging can be performed by converting AC power into DC power via a conversion device such as an AC-DC converter. When charging, the charging method, the standard of the connector, etc. may be appropriately performed in a predetermined manner. The charging device 8021 may be a charging station provided in a commercial facility or may be a household power source. For example, by the plug-in technology, the storage battery 8024 mounted on the automobile 8100 can be charged by external power supply. Charging can be performed by converting AC power into DC power via a conversion device such as an AC-DC converter.

[0204] Also, although not shown, a power receiving device may be mounted on the vehicle, and power may be supplied non-contact from a power transmission device on the ground for charging. In the case of this non-contact power supply method, by incorporating a power transmission device into a road or an outer wall, charging can be performed not only while the vehicle is stopped but also while it is running. Further, power transmission and reception may be performed between vehicles using this non-contact power supply method. Furthermore, a solar cell may be provided on the exterior of the vehicle to charge the storage battery when the vehicle is stopped or running. For such non-contact power supply, an electromagnetic induction method or a magnetic field resonance method can be used. Also, although not shown, a power receiving device may be mounted on the vehicle, and power may be supplied non-contact from a power transmission device on the ground for charging. In the case of this non-contact power supply method, by incorporating a power transmission device into a road or an outer wall, charging can be performed not only while the vehicle is stopped but also while it is running. Further, power transmission and reception may be performed between vehicles using this non-contact power supply method. Furthermore, a solar cell may be provided on the exterior of the vehicle to charge the storage battery when the vehicle is stopped or running. For such non-contact power supply, an electromagnetic induction method or a magnetic field resonance method can be used. Also, although not shown, a power receiving device may be mounted on the vehicle, and power may be supplied non-contact from a power transmission device on the ground for charging. In the case of this non-contact power supply method, by incorporating a power transmission device into a road or an outer wall, charging can be performed not only while the vehicle is stopped but also while it is running. Further, power transmission and reception may be performed between vehicles using this non-contact power supply method. Furthermore, a solar cell may be provided on the exterior of the vehicle to charge the storage battery when the vehicle is stopped or running. For such non-contact power supply, an electromagnetic induction method or a magnetic field resonance method can be used. Also, although not shown, a power receiving device may be mounted on the vehicle, and power may be supplied non-contact from a power transmission device on the ground for charging. In the case of this non-contact power supply method, by incorporating a power transmission device into a road or an outer wall, charging can be performed not only while the vehicle is stopped but also while it is running. Further, power transmission and reception may be performed between vehicles using this non-contact power supply method. Furthermore, a solar cell may be provided on the exterior of the vehicle to charge the storage battery when the vehicle is stopped or running. For such non-contact power supply, an electromagnetic induction method or a magnetic field resonance method can be used. Also, although not shown, a power receiving device may be mounted on the vehicle, and power may be supplied non-contact from a power transmission device on the ground for charging. In the case of this non-contact power supply method, by incorporating a power transmission device into a road or an outer wall, charging can be performed not only while the vehicle is stopped but also while it is running. Further, power transmission and reception may be performed between vehicles using this non-contact power supply method. Furthermore, a solar cell may be provided on the exterior of the vehicle to charge the storage battery when the vehicle is stopped or running. For such non-contact power supply, an electromagnetic induction method or a magnetic field resonance method can be used. Also, although not shown, a power receiving device may be mounted on the vehicle, and power may be supplied non-contact from a power transmission device on the ground for charging. In the case of this non-contact power supply method, by incorporating a power transmission device into a road or an outer wall, charging can be performed not only while the vehicle is stopped but also while it is running. Further, power transmission and reception may be performed between vehicles using this non-contact power supply method. Furthermore, a solar cell may be provided on the exterior of the vehicle to charge the storage battery when the vehicle is stopped or running. For such non-contact power supply, an electromagnetic induction method or a magnetic field resonance method can be used.

[0205] According to one aspect of the present invention, the cycle characteristics of the storage battery are improved, and the reliability is enhanced. It becomes possible. Further, according to one aspect of the present invention, the characteristics of the storage battery can be improved, and thus , the storage battery itself can be made smaller and lighter. If the storage battery itself can be made smaller and lighter, it contributes to the weight reduction of the vehicle, and thus the cruising range can be improved. In addition, the storage battery mounted on the vehicle can also be used as a power supply source other than the vehicle. In this case, it is possible to avoid using the commercial power supply at the peak of the power demand.

[0206] This embodiment can be implemented in appropriate combination with other embodiments.

[0207] (Embodiment 3) A battery control unit (Battery Management Unit: BMU ) that can be used in combination with the storage battery described in Embodiments 1 and 2 as battery cells, and a transistor suitable for the circuit constituting the battery control unit will be described with reference to FIGS. 22 to 28. In this embodiment, a battery control unit for a storage battery having battery cells connected in series will be described in particular.

[0208] When charging and discharging are repeatedly performed on a plurality of battery cells connected in series, the characteristics between the battery cells vary, and the capacity (output voltage) becomes different. In battery cells connected in series , the overall capacity during discharge depends on the battery cell with the smallest capacity. If there is a variation in capacity, the capacity during discharge becomes small. Further, if charging is performed based on the battery cell with the smallest capacity, there is a risk of insufficient charging. On the other hand, if charging is performed based on the battery cell with the largest capacity, there is a risk of overcharging.

[0209] Therefore, the battery control unit for a storage battery having battery cells connected in series prevents insufficient charging and It has a function of equalizing the capacity variations between battery cells that cause overcharging. Between battery cells Circuit configurations for equalizing the capacity variations between battery cells include a resistance method, a capacitor method, an inductor method, etc. Here, as an example, a circuit configuration capable of equalizing the capacity variations by using a transistor with a small off-current will be described.

[0210] As a transistor with a small off-current, a transistor having an oxide semiconductor in the channel formation region (OS transistor) is preferable. By using an OS transistor with a small off-current in the circuit configuration of the battery control unit of the storage battery the amount of charge leaking from the battery can be reduced, and a decrease in capacity over time can be suppressed.

[0211] The oxide semiconductor used in the channel formation region is In-M-Zn oxide (M is Ga, Sn, Y, Zr, La, Ce, or Nd). In the target used for forming the oxide semiconductor film the atomic ratio of metal elements is In:M:Zn = x 1 :y 1 :z 1 Then 、 x 1 / y 1 is 1 / 3 or more and 6 or less, further 1 or more and 6 or less, and z 1 / y 1 is preferably 1 / 3 or more and 6 or less, further 1 or more and 6 or less. Note that making z 1 / y 1 1 or more and 6 or less makes it easier to form a CAAC-OS film as the oxide semiconductor film.

[0212] Here, the CAAC-OS film will be described.

[0213] ​​​The CAAC-OS film is one of the oxide semiconductor films having a plurality of crystal parts oriented in the c-axis direction.

[0214] By using a transmission electron microscope (TEM), a composite analysis image of the bright-field image and the diffraction pattern of the CAAC-OS film ( also referred to as a high-resolution TEM image) can be observed to confirm a plurality of crystal parts. On the other hand, even with a high-resolution TEM image, it is not possible to confirm the boundaries between distinct crystal parts, that is, grain boundaries (also referred to as grain boundaries). Therefore, it can be said that in the CAAC-OS film, a decrease in electron mobility due to grain boundaries is unlikely to occur. When observing a high-resolution TEM image of the cross-section of the CAAC-OS film from a direction substantially parallel to the sample surface, it can be confirmed that metal atoms are arranged in layers in the crystal part. Each layer of metal atoms has a shape that reflects the unevenness of the surface (also referred to as the film-forming surface) or the upper surface of the CAAC-OS film, and is arranged parallel to the film-forming surface or the upper surface of the CAAC-OS film.

[0215] When observing a high-resolution TEM image of the plane of the CAAC-OS film from a direction substantially perpendicular to the sample surface, it can be confirmed that metal atoms are arranged in a triangular or hexagonal shape in the crystal part. However, no regularity is observed in the arrangement of metal atoms between different crystal parts. When performing structural analysis on the CAAC-OS film using an X-ray diffraction (XRD) apparatus, for example, in the out-of-plane method analysis of the CAAC-OS film having InGaZnO

[0216] crystals, a peak appears at around a diffraction angle (2θ) of 31°. When observing a high-resolution TEM image of the plane of the CAAC-OS film from a direction substantially perpendicular to the sample surface, it can be confirmed that metal atoms are arranged in a triangular or hexagonal shape in the crystal part. However, no regularity is observed in the arrangement of metal atoms between different crystal parts.

[0217] When performing structural analysis on the CAAC-OS film using an X-ray diffraction (XRD) apparatus, for example, in the out-of-plane method analysis of the CAAC-OS film having InGaZnO 4 crystals, a peak appears at around a diffraction angle (2θ) of 31°. In the out-of-plane method analysis of the CAAC-OS film having InGaZnO may appear. This peak is attributed to the (009) plane of the InGaZnO 4 crystal, indicating that the crystal of the CAAC-OS film has c-axis orientation and the c-axis is oriented substantially perpendicular to the surface to be formed or the upper surface.

[0218] Note that in the out-of-plane method analysis of the CAAC-OS film having InGaZnO 4 crystals, in addition to the peak with 2θ around 31°, a peak may also appear at around 2θ = 36° in some cases. The peak with 2θ around 36° indicates that a part of the CAAC-OS film contains crystals without c-axis orientation. It is preferable that the CAAC-OS film shows a peak at around 2θ = 31° and does not show a peak at around 2θ = 36°.

[0219] The CAAC-OS film is an oxide semiconductor film with a low impurity concentration. Impurities are elements other than the main components of the oxide semiconductor film, such as hydrogen, carbon, silicon, and transition metal elements. In particular, elements with a stronger binding force with oxygen than the metal elements constituting the oxide semiconductor film, such as silicon, will disrupt the atomic arrangement of the oxide semiconductor film and reduce the crystallinity by taking oxygen from the oxide semiconductor film. Also, heavy metals such as iron and nickel, argon, carbon dioxide, etc., have a large atomic radius (or molecular radius), so when contained inside the oxide semiconductor film, they will disrupt the atomic arrangement of the oxide semiconductor film and reduce the crystallinity. Note that impurities contained in the oxide semiconductor film may become carrier traps or carrier generation sources. (or molecular radius), so when contained inside the oxide semiconductor film, they will disrupt the atomic arrangement of the oxide semiconductor film and reduce the crystallinity. Note that impurities contained in the oxide semiconductor film may become carrier traps or carrier generation sources.

[0220] In addition, the CAAC-OS film is an oxide semiconductor film with a low defect level density. For example, the oxide Oxygen deficiencies in the semiconductor film can act as carrier traps or capture hydrogen, thereby becoming a carrier generation source.

[0221] A low impurity concentration and a low defect level density (few oxygen deficiencies) are referred to as high-purity intrinsic or substantially high-purity intrinsic. An oxide semiconductor film that is high-purity intrinsic or substantially high-purity intrinsic has few carrier generation sources, so the carrier density can be lowered. Therefore, a transistor using such an oxide semiconductor film is less likely to have an electrical characteristic ([[]]END]] also called normally-on.) in which the threshold voltage becomes negative. In addition, an oxide semiconductor film that is high-purity intrinsic or substantially high [[[]]END]] purity intrinsic has few carrier traps. Therefore, a transistor using such an oxide semiconductor [[[]]END]] film has small fluctuations in electrical characteristics and becomes a highly reliable transistor. [[[]]END]] Note that the charge trapped in the carrier trap of the oxide semiconductor film may take a long time to be released and may behave like a fixed charge. Therefore, a transistor using an oxide semiconductor film with a [[[]]END]] high impurity concentration and a high defect level density may have unstable electrical characteristics. [[[]]END]]

[0222] In addition, a transistor using a CAAC-OS film has small fluctuations in electrical characteristics due to irradiation with visible light or ultraviolet light. [[[]]END]]

[0223] Note that an OS transistor has a larger bandgap than a transistor (Si transistor) having silicon in the channel formation region, so breakdown is less likely to occur when a high voltage is applied. When battery cells are connected in series, a voltage of several hundred volts will be generated, but in the circuit configuration of the battery control unit of a storage battery applied to such battery cells, the aforementioned OS transistor [[[]]END]] It is suitable to be composed of transistors.

[0224] Fig. 22 shows an example of a block diagram of a storage battery. The storage battery BT00 shown in Fig. 22 has a terminal pair BT01, a terminal pair BT02, a switching control circuit BT03, a switching circuit BT04 , a switching circuit BT05, a voltage conversion control circuit BT06, a voltage conversion circuit BT07, and a battery unit BT08 including a plurality of battery cells BT09 connected in series .

[0225] Also, in the storage battery BT00 of Fig. 22, the part composed of the terminal pair BT01, the terminal pair BT02, the switching control circuit BT03, the switching circuit BT04, the switching circuit BT05, the voltage conversion control circuit BT06, and the voltage conversion circuit BT07 can be called a battery control unit.

[0226] The switching control circuit BT03 controls the operations of the switching circuit BT04 and the switching circuit BT05. Specifically, the switching control circuit BT03 determines the battery cells to be discharged (discharge battery cell group) and the battery cells to be charged (charge battery cell group) based on the voltages measured for each battery cell BT09.

[0227] Furthermore, the switching control circuit BT03 outputs a control signal S1 and a control signal S2 based on the determined discharge battery cell group and charge battery cell group. The control signal S1 is output to the switching circuit BT04. This control signal S1 is a signal for controlling the switching circuit BT04 so as to connect the terminal pair BT01 and the discharge battery cell group. Also, the control signal S2 is output to the switching circuit BT05. This control signal S2 is a signal for controlling the switching circuit BT05 so as to connect the terminal pair BT02 and the charge battery cell group. ​

[0228] Also, based on the configurations of the switching circuit BT04, the switching circuit BT05, and the transformer circuit BT07, the switching control circuit BT03 generates the control signal S1 and the control signal S2 so that the terminals with the same polarity are connected between the terminal pair BT02 and the rechargeable battery cell group. Based on the configurations of the switching circuit BT04, the switching circuit BT05, and the transformer circuit BT07, the switching control circuit BT03 generates the control signal S1 and the control signal S2 so that the terminals with the same polarity are connected between the terminal pair BT02 and the rechargeable battery cell group. Also, based on the configurations of the switching circuit BT04, the switching circuit BT05, and the transformer circuit BT07, the switching control circuit BT03 generates the control signal S1 and the control signal S2 so that the terminals with the same polarity are connected between the terminal pair BT02 and the rechargeable battery cell group.

[0229] Describe the details of the operation of the switching control circuit BT03.

[0230] First, the switching control circuit BT03 measures the voltage of each of the plurality of battery cells BT09. Then, the switching control circuit BT03 determines, for example, a battery cell BT09 having a voltage equal to or higher than a predetermined threshold as a high-voltage battery cell (high-voltage cell), and a battery cell BT09 having a voltage lower than the predetermined threshold as a low-voltage battery cell (constant-voltage cell). First, the switching control circuit BT03 measures the voltage of each of the plurality of battery cells BT09. Then, the switching control circuit BT03 determines, for example, a battery cell BT09 having a voltage equal to or higher than a predetermined threshold as a high-voltage battery cell (high-voltage cell), and a battery cell BT09 having a voltage lower than the predetermined threshold as a low-voltage battery cell (constant-voltage cell). First, the switching control circuit BT03 measures the voltage of each of the plurality of battery cells BT09. Then, the switching control circuit BT03 determines, for example, a battery cell BT09 having a voltage equal to or higher than a predetermined threshold as a high-voltage battery cell (high-voltage cell), and a battery cell BT09 having a voltage lower than the predetermined threshold as a low-voltage battery cell (constant-voltage cell). First, the switching control circuit BT03 measures the voltage of each of the plurality of battery cells BT09. Then, the switching control circuit BT03 determines, for example, a battery cell BT09 having a voltage equal to or higher than a predetermined threshold as a high-voltage battery cell (high-voltage cell), and a battery cell BT09 having a voltage lower than the predetermined threshold as a low-voltage battery cell (constant-voltage cell).

[0231] Note that various methods can be used to determine the high-voltage cells and the low-voltage cells. For example, the switching control circuit BT03 may determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell based on the voltage of the battery cell BT09 having the highest or lowest voltage among the plurality of battery cells BT09. In this case, the switching control circuit BT03 can determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell by determining whether the voltage of each battery cell BT09 is equal to or higher than a predetermined ratio with respect to the reference voltage. Then, the switching control circuit BT03 determines the discharge battery cell group and the rechargeable battery cell group based on this determination result. Note that various methods can be used to determine the high-voltage cells and the low-voltage cells. For example, the switching control circuit BT03 may determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell based on the voltage of the battery cell BT09 having the highest or lowest voltage among the plurality of battery cells BT09. In this case, the switching control circuit BT03 can determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell by determining whether the voltage of each battery cell BT09 is equal to or higher than a predetermined ratio with respect to the reference voltage. Then, the switching control circuit BT03 determines the discharge battery cell group and the rechargeable battery cell group based on this determination result. Note that various methods can be used to determine the high-voltage cells and the low-voltage cells. For example, the switching control circuit BT03 may determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell based on the voltage of the battery cell BT09 having the highest or lowest voltage among the plurality of battery cells BT09. In this case, the switching control circuit BT03 can determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell by determining whether the voltage of each battery cell BT09 is equal to or higher than a predetermined ratio with respect to the reference voltage. Then, the switching control circuit BT03 determines the discharge battery cell group and the rechargeable battery cell group based on this determination result. Note that various methods can be used to determine the high-voltage cells and the low-voltage cells. For example, the switching control circuit BT03 may determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell based on the voltage of the battery cell BT09 having the highest or lowest voltage among the plurality of battery cells BT09. In this case, the switching control circuit BT03 can determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell by determining whether the voltage of each battery cell BT09 is equal to or higher than a predetermined ratio with respect to the reference voltage. Then, the switching control circuit BT03 determines the discharge battery cell group and the rechargeable battery cell group based on this determination result. Note that various methods can be used to determine the high-voltage cells and the low-voltage cells. For example, the switching control circuit BT03 may determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell based on the voltage of the battery cell BT09 having the highest or lowest voltage among the plurality of battery cells BT09. In this case, the switching control circuit BT03 can determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell by determining whether the voltage of each battery cell BT09 is equal to or higher than a predetermined ratio with respect to the reference voltage. Then, the switching control circuit BT03 determines the discharge battery cell group and the rechargeable battery cell group based on this determination result. Note that various methods can be used to determine the high-voltage cells and the low-voltage cells. For example, the switching control circuit BT03 may determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell based on the voltage of the battery cell BT09 having the highest or lowest voltage among the plurality of battery cells BT09. In this case, the switching control circuit BT03 can determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell by determining whether the voltage of each battery cell BT09 is equal to or higher than a predetermined ratio with respect to the reference voltage. Then, the switching control circuit BT03 determines the discharge battery cell group and the rechargeable battery cell group based on this determination result. Note that various methods can be used to determine the high-voltage cells and the low-voltage cells. For example, the switching control circuit BT03 may determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell based on the voltage of the battery cell BT09 having the highest or lowest voltage among the plurality of battery cells BT09. In this case, the switching control circuit BT03 can determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell by determining whether the voltage of each battery cell BT09 is equal to or higher than a predetermined ratio with respect to the reference voltage. Then, the switching control circuit BT03 determines the discharge battery cell group and the rechargeable battery cell group based on this determination result. Note that various methods can be used to determine the high-voltage cells and the low-voltage cells. For example, the switching control circuit BT03 may determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell based on the voltage of the battery cell BT09 having the highest or lowest voltage among the plurality of battery cells BT09. In this case, the switching control circuit BT03 can determine whether each battery cell BT09 is a high-voltage cell or a low-voltage cell by determining whether the voltage of each battery cell BT09 is equal to or higher than a predetermined ratio with respect to the reference voltage. Then, the switching control circuit BT03 determines the discharge battery cell group and the rechargeable battery cell group based on this determination result.

[0232] Note that among the plurality of battery cells BT09, high-voltage cells and low-voltage cells are mixed in various states. obtained. For example, in the case where high-voltage cells and low-voltage cells are mixed, the part where the highest number of high-voltage cells are continuously connected in series is defined as the discharge battery cell group. Also, the switching control circuit BT03 defines the part where the highest number of low-voltage cells are continuously connected in series as the charge battery cell group. Further, the switching control circuit BT03 may preferentially select a battery cell BT09 that is close to overcharge or over-discharge as the discharge battery cell group or the charge battery cell group.

[0233] Here, an operation example of the switching control circuit BT03 in this embodiment will be described with reference to FIG. 23. FIG. 23 is a diagram for explaining an operation example of the switching control circuit BT03. For the sake of convenience of explanation, in FIG. 23, the case where four battery cells BT09 are connected in series will be described as an example.

[0234] First, in the example of FIG. 23(A), assuming that the voltages of battery cells a to d are voltage Va to voltage Vd, the relationship Va = Vb = Vc > Vd is shown. That is, three consecutive high-voltage cells a to c and one low-voltage cell d are connected in series. In this case, the switching control circuit BT03 determines the three consecutive high-voltage cells a to c as the discharge battery cell group. Also, the switching control circuit BT03 determines the low-voltage cell D as the charge battery cell group.

[0235] Next, in the example of FIG. 23(B), the relationship Vc > Vb = Vc >> Vd is shown. That is, two consecutive low-voltage cells a, b, one high-voltage cell c, and one low-voltage cell d close to over-discharge are connected in series. In this case, the switching control circuit BT03 ​​​​​​​​​The high-voltage cell c is determined as the discharge battery cell group. Also, the switching control circuit BT03 determines the low-voltage cell d as the charge battery cell group preferentially instead of the two consecutive low-voltage cells a and b because the low-voltage cell d is approaching over-discharge. Finally, in the example of Fig. 23(C), the case where Va > Vb = Vc = Vd is shown. That is, one high-voltage cell a and three consecutive low-voltage cells b to d are connected in series. In this case, the switching control circuit BT03 determines the high-voltage cell a as the discharge battery cell group. Also, the switching control circuit BT03 determines the three consecutive low-voltage cells b to d as the charge battery cell group. Based on the results determined as in the examples of Figs. 23(A) to (C) above, the switching control circuit BT03 outputs the control signal S1 in which the information indicating the discharge battery cell group which is the connection destination of the switching circuit BT04 is set, and the control signal S2 in which the information indicating the charge battery cell group which is the connection destination of the switching circuit BT05 is set, to the switching circuit BT04 and the switching circuit BT05 respectively.

[0236] The above is the explanation regarding the details of the operation of the switching control circuit BT03. That is, one high-voltage cell a and three consecutive low-voltage cells b to d are connected in series. In this case, the switching control circuit BT03 determines the high-voltage cell a as the discharge battery cell group. Also, the switching control circuit BT03 determines the three consecutive low-voltage cells b to d as the charge battery cell group. Based on the results determined as in the examples of Figs. 23(A) to (C) above, the switching control circuit BT03 outputs the control signal S1 in which the information indicating the discharge battery cell group which is the connection destination of the switching circuit BT04 is set, and the control signal S2 in which the information indicating the charge battery cell group which is the connection destination of the switching circuit BT05 is set, to the switching circuit BT04 and the switching circuit BT05 respectively. The above is the explanation regarding the details of the operation of the switching control circuit BT03. The switching circuit BT04 sets the connection destination of the terminal pair BT01 to the discharge battery cell group determined by the switching control circuit BT03 according to the control signal S1 output from the switching control circuit BT03.

[0237] The terminal pair BT01 is composed of the paired terminals A1 and A2. The switching circuit BT04 sets the connection destination of the terminal pair BT01 to the discharge battery cell group determined by the switching control circuit BT03 according to the control signal S1 output from the switching control circuit BT03. The terminal pair BT01 is composed of the paired terminals A1 and A2. The switching circuit BT04 sets the connection destination of the terminal pair BT01 to the discharge battery cell group determined by the switching control circuit BT03 according to the control signal S1 output from the switching control circuit BT03. The above is the explanation regarding the details of the operation of the switching control circuit BT03.

[0238] The above is the explanation regarding the details of the operation of the switching control circuit BT03.

[0239] The switching circuit BT04 sets the connection destination of the terminal pair BT01 to the discharge battery cell group determined by the switching control circuit BT03 according to the control signal S1 output from the switching control circuit BT03. The terminal pair BT01 is composed of the paired terminals A1 and A2. The switching circuit BT04 sets the connection destination of the terminal pair BT01 to the discharge battery cell group determined by the switching control circuit BT03 according to the control signal S1 output from the switching control circuit BT03.

[0240] The terminal pair BT01 is composed of the paired terminals A1 and A2. Of these terminals A1 and A2, connect either one to the positive terminal of the battery cell BT09 located most upstream (higher potential side) in the discharge battery cell group, and connect the other to the negative terminal of the battery cell BT09 located most downstream (lower potential side) in the discharge battery cell group, thereby setting the connection destination of the terminal pair BT01. Note that the switching circuit BT04 can recognize the position of the discharge battery cell group using the information set in the control signal S1. Connect either one of these terminals A1 and A2 to the positive terminal of the battery cell BT09 located most upstream (higher potential side) in the discharge battery cell group, and connect the other to the negative terminal of the battery cell BT09 located most downstream (lower potential side) in the discharge battery cell group, thereby setting the connection destination of the terminal pair BT01. Note that the switching circuit BT04 can recognize the position of the discharge battery cell group using the information set in the control signal S1. Connect either one of these terminals A1 and A2 to the positive terminal of the battery cell BT09 located most upstream (higher potential side) in the discharge battery cell group, and connect the other to the negative terminal of the battery cell BT09 located most downstream (lower potential side) in the discharge battery cell group, thereby setting the connection destination of the terminal pair BT01. Note that the switching circuit BT04 can recognize the position of the discharge battery cell group using the information set in the control signal S1. Connect either one of these terminals A1 and A2 to the positive terminal of the battery cell BT09 located most upstream (higher potential side) in the discharge battery cell group, and connect the other to the negative terminal of the battery cell BT09 located most downstream (lower potential side) in the discharge battery cell group, thereby setting the connection destination of the terminal pair BT01. Note that the switching circuit BT04 can recognize the position of the discharge battery cell group using the information set in the control signal S1. Connect either one of these terminals A1 and A2 to the positive terminal of the battery cell BT09 located most upstream (higher potential side) in the discharge battery cell group, and connect the other to the negative terminal of the battery cell BT09 located most downstream (lower potential side) in the discharge battery cell group, thereby setting the connection destination of the terminal pair BT01. Note that the switching circuit BT04 can recognize the position of the discharge battery cell group using the information set in the control signal S1.

[0241] The switching circuit BT05 sets the connection destination of the terminal pair BT02 to the charging battery cell group determined by the switching control circuit BT03 according to the control signal S2 output from the switching control circuit BT03. The switching circuit BT05 sets the connection destination of the terminal pair BT02 to the charging battery cell group determined by the switching control circuit BT03 according to the control signal S2 output from the switching control circuit BT03. The switching circuit BT05 sets the connection destination of the terminal pair BT02 to the charging battery cell group determined by the switching control circuit BT03 according to the control signal S2 output from the switching control circuit BT03.

[0242] The terminal pair BT02 is composed of paired terminals B1 and B2. The switching circuit BT05 connects either one of these terminals B1 and B2 to the positive terminal of the battery cell BT09 located most upstream (higher potential side) in the charging battery cell group, and connects the other to the negative terminal of the battery cell BT09 located most downstream (lower potential side) in the charging battery cell group, thereby setting the connection destination of the terminal pair BT02. Note that the switching circuit BT05 can recognize the position of the charging battery cell group using the information set in the control signal S2. Of these terminals B1 and B2, connect either one to the positive terminal of the battery cell BT09 located most upstream (higher potential side) in the charging battery cell group, and connect the other to the negative terminal of the battery cell BT09 located most downstream (lower potential side) in the charging battery cell group, thereby setting the connection destination of the terminal pair BT02. Note that the switching circuit BT05 can recognize the position of the charging battery cell group using the information set in the control signal S2. Of these terminals B1 and B2, connect either one to the positive terminal of the battery cell BT09 located most upstream (higher potential side) in the charging battery cell group, and connect the other to the negative terminal of the battery cell BT09 located most downstream (lower potential side) in the charging battery cell group, thereby setting the connection destination of the terminal pair BT02. Note that the switching circuit BT05 can recognize the position of the charging battery cell group using the information set in the control signal S2. Of these terminals B1 and B2, connect either one to the positive terminal of the battery cell BT09 located most upstream (higher potential side) in the charging battery cell group, and connect the other to the negative terminal of the battery cell BT09 located most downstream (lower potential side) in the charging battery cell group, thereby setting the connection destination of the terminal pair BT02. Note that the switching circuit BT05 can recognize the position of the charging battery cell group using the information set in the control signal S2. Of these terminals B1 and B2, connect either one to the positive terminal of the battery cell BT09 located most upstream (higher potential side) in the charging battery cell group, and connect the other to the negative terminal of the battery cell BT09 located most downstream (lower potential side) in the charging battery cell group, thereby setting the connection destination of the terminal pair BT02. Note that the switching circuit BT05 can recognize the position of the charging battery cell group using the information set in the control signal S2. Of these terminals B1 and B2, connect either one to the positive terminal of the battery cell BT09 located most upstream (higher potential side) in the charging battery cell group, and connect the other to the negative terminal of the battery cell BT09 located most downstream (lower potential side) in the charging battery cell group, thereby setting the connection destination of the terminal pair BT02. Note that the switching circuit BT05 can recognize the position of the charging battery cell group using the information set in the control signal S2.

[0243] Circuit diagrams showing configuration examples of the switching circuit BT04 and the switching circuit BT05 are shown in FIGS. 24 and 25. Circuit diagrams showing configuration examples of the switching circuit BT04 and the switching circuit BT05 are shown in FIGS. 24 and 25.

[0244] In FIG. 24, the switching circuit BT04 has a plurality of transistors BT10, and buses BT11 and BT12. The bus BT11 is connected to the terminal A1. Also, the bus BT1 In FIG. 24, the switching circuit BT04 has a plurality of transistors BT10, and buses BT11 and BT12. The bus BT11 is connected to the terminal A1. Also, the bus BT1 2 is connected to terminal A2. One of the sources or drains of the plurality of transistors BT10 is alternately connected to buses BT11 and BT12 every other one. Also the other of the sources or drains of the plurality of transistors BT10 is connected between every two adjacent battery cells BT09.

[0245] Note that among the plurality of transistors BT10, the other of the source or drain of the transistor BT10 located at the most upstream is connected to the positive terminal of the battery cell BT09 located at the most upstream of the battery section BT08. Also, among the plurality of transistors BT10, the other of the source or drain of the transistor BT10 located at the most downstream is connected to the negative terminal of the battery cell BT09 located at the most downstream of the battery section BT08.

[0246] The switching circuit BT04, according to the control signal S1 applied to the gates of the plurality of transistors BT10, conducts one of the plurality of transistors BT10 connected to bus BT11 and one of the plurality of transistors BT10 connected to bus B T12 respectively, thereby connecting the discharge battery cell group and the terminal pair BT01. As a result, the positive terminal of the battery cell BT09 located at the most upstream in the discharge battery cell group is connected to either terminal A1 or A 2 of the terminal pair. Also, the negative terminal of the battery cell BT09 located at the most downstream in the discharge battery cell group is connected to the other of terminal A1 or A2 of the terminal pair, that is, the terminal not connected to the positive terminal.

[0247] It is preferable to use an OS transistor for the transistor BT10. OS transistor Since the leakage current of the transistor is small, the amount of charge leaking from the battery cells not belonging to the discharge battery cell group can be reduced, and the decrease in capacity over time can be suppressed. Also, the OS transistor is less likely to break down when a high voltage is applied. Therefore, even when the output voltage of the discharge battery cell group is large, the battery cell BT09 to which the non-conducting transistor BT10 is connected and the terminal pair BT01 can be insulated from each other. Further, in FIG. 24, the switching circuit BT05 includes a plurality of transistors BT13, a current control switch BT14, a bus BT15, and a bus BT16. The buses BT15 and BT16 are arranged between the plurality of transistors BT13 and the current control switch BT14. One of the sources or drains of the plurality of transistors BT13 is alternately connected to the buses BT15 and BT16 every other one. Also, the other of the sources or drains of the plurality of transistors BT13 is connected between two adjacent battery cells BT09. Incidentally, among the plurality of transistors BT13, the other of the source or drain of the transistor BT13 located at the most upstream is connected to the positive terminal of the battery cell BT09 located at the most upstream of the battery unit BT08. Also, among the plurality of transistors BT13, the other of the source or drain of the transistor BT13 located at the most downstream is connected to the negative terminal of the battery cell BT09 located at the most downstream of the battery unit BT08. It is preferable to use an OS transistor for the transistor BT13 as well as for the transistor BT10. Since the OS transistor has a small off-current, it can prevent charge leakage from the battery cells not belonging to the rechargeable battery cell group.

[0248] Also, in FIG. 24, the switching circuit BT05 has a plurality of transistors BT13, a current control switch BT14, a bus BT15, and a bus BT16. The buses BT15 and BT16 are disposed between the plurality of transistors BT13 and the current control switch BT14. One of the sources or drains of the plurality of transistors BT13 is alternately connected to the buses BT15 and BT16 every other one. And the other of the sources or drains of the plurality of transistors BT13 is connected between two adjacent battery cells BT09. Among the plurality of transistors BT13, the other of the source or drain of the transistor BT13 located at the most upstream is connected to the positive terminal of the battery cell BT09 located at the most upstream of the battery unit BT08.

[0249] Among the plurality of transistors BT13, the other of the source or drain of the transistor BT13 located at the most downstream is connected to the negative terminal of the battery cell BT09 located at the most downstream of the battery unit BT08. It is preferable to use an OS transistor for the transistor BT13 as in the case of the transistor BT10. Since the OS transistor has a small off-current, it can prevent charge leakage from the battery cells not belonging to the rechargeable battery cell group.

[0250] For the transistor BT13, it is preferable to use an OS transistor as in the case of the transistor BT10. Since the OS transistor has a small off-current, charge leakage from battery cells not belonging to the rechargeable battery cell group can be prevented.​​​​​ It is possible to reduce the amount of charge leaking from the battery cell and suppress the decrease in capacity over time. In addition, the OS transistor is less likely to break down when a high voltage is applied. Therefore, even if the voltage for charging the rechargeable battery cell group is large, the battery cell BT09 to which the non-conductive transistor BT 13 is connected and the terminal pair BT02 can be insulated.

[0251] The current control switch BT14 has a switch pair BT17 and a switch pair BT18. The one end of the switch pair BT17 is connected to the terminal B1. Also, the other end of the switch pair BT17 branches into two switches, one switch is connected to the bus BT15, and the other switch is connected to the bus BT16. One end of the switch pair BT18 is connected to the terminal B2. Also, the other end of the switch pair BT18 branches into two switches, one switch is connected to the bus BT15, and the other switch is connected to the bus BT16. .

[0252] The switches included in the switch pair BT17 and the switch pair BT18 are preferably OS transistors, similar to the transistor BT10 and the transistor BT13.

[0253] The switching circuit BT05 controls the combination of the on / off states of the transistor BT13 and the current control switch BT14 according to the control signal S2, thereby connecting the rechargeable battery cell group to the terminal pair BT02.

[0254] As an example, the switching circuit BT05 connects the rechargeable battery cell group to the terminal pair BT0 2 as follows.

[0255] The switching circuit BT05 turns on the transistor BT13 connected to the positive terminal of the battery cell BT09 located most upstream in the rechargeable battery cell group according to the control signal S2 applied to the gates of the plurality of transistors BT10. Also, the switching circuit BT05 turns on the transistor BT13 connected to the negative terminal of the battery cell BT09 located most downstream in the rechargeable battery cell group according to the control signal S2 applied to the gates of the plurality of transistors BT10. Depending on the control signal S2 applied to the gates of the plurality of transistors BT10, the transistor BT13 connected to the positive terminal of the battery cell BT09 located most upstream in the rechargeable battery cell group is turned on. Also, the switching circuit BT05 turns on the transistor BT13 connected to the negative terminal of the battery cell BT09 located most downstream in the rechargeable battery cell group according to the control signal S2 applied to the gates of the plurality of transistors BT10. Depending on the control signal S2 applied to the gates of the plurality of transistors BT10, the transistor BT13 connected to the positive terminal of the battery cell BT09 located most upstream in the rechargeable battery cell group is turned on. Also, the switching circuit BT05 turns on the transistor BT13 connected to the negative terminal of the battery cell BT09 located most downstream in the rechargeable battery cell group according to the control signal S2 applied to the gates of the plurality of transistors BT10. Depending on the control signal S2 applied to the gates of the plurality of transistors BT10, the transistor BT13 connected to the positive terminal of the battery cell BT09 located most upstream in the rechargeable battery cell group is turned on. Also, the switching circuit BT05 turns on the transistor BT13 connected to the negative terminal of the battery cell BT09 located most downstream in the rechargeable battery cell group according to the control signal S2 applied to the gates of the plurality of transistors BT10. Depending on the control signal S2 applied to the gates of the plurality of transistors BT10, the transistor BT13 connected to the positive terminal of the battery cell BT09 located most upstream in the rechargeable battery cell group is turned on. Also, the switching circuit BT05 turns on the transistor BT13 connected to the negative terminal of the battery cell BT09 located most downstream in the rechargeable battery cell group according to the control signal S2 applied to the gates of the plurality of transistors BT10. Depending on the control signal S2 applied to the gates of the plurality of transistors BT10, the transistor BT13 connected to the positive terminal of the battery cell BT09 located most upstream in the rechargeable battery cell group is turned on. Also, the switching circuit BT05 turns on the transistor BT13 connected to the negative terminal of the battery cell BT09 located most downstream in the rechargeable battery cell group according to the control signal S2 applied to the gates of the plurality of transistors BT10.

[0256] The polarity of the voltage applied to the terminal pair BT02 can vary depending on the discharge battery cell group connected to the terminal pair BT01 and the configuration of the transformer circuit BT07. Also, in order to flow a current in the charging direction of the rechargeable battery cell group, it is necessary to connect terminals of the same polarity between the terminal pair BT02 and the rechargeable battery cell group. Therefore, the current control switch BT14 is controlled by the control signal S2 to switch the connection destinations of the switch pair BT17 and the switch pair BT18 according to the polarity of the voltage applied to the terminal pair BT02. The polarity of the voltage applied to the terminal pair BT02 can vary depending on the discharge battery cell group connected to the terminal pair BT01 and the configuration of the transformer circuit BT07. Also, in order to flow a current in the charging direction of the rechargeable battery cell group, it is necessary to connect terminals of the same polarity between the terminal pair BT02 and the rechargeable battery cell group. Therefore, the current control switch BT14 is controlled by the control signal S2 to switch the connection destinations of the switch pair BT17 and the switch pair BT18 according to the polarity of the voltage applied to the terminal pair BT02. The polarity of the voltage applied to the terminal pair BT02 can vary depending on the discharge battery cell group connected to the terminal pair BT01 and the configuration of the transformer circuit BT07. Also, in order to flow a current in the charging direction of the rechargeable battery cell group, it is necessary to connect terminals of the same polarity between the terminal pair BT02 and the rechargeable battery cell group. Therefore, the current control switch BT14 is controlled by the control signal S2 to switch the connection destinations of the switch pair BT17 and the switch pair BT18 according to the polarity of the voltage applied to the terminal pair BT02. The polarity of the voltage applied to the terminal pair BT02 can vary depending on the discharge battery cell group connected to the terminal pair BT01 and the configuration of the transformer circuit BT07. Also, in order to flow a current in the charging direction of the rechargeable battery cell group, it is necessary to connect terminals of the same polarity between the terminal pair BT02 and the rechargeable battery cell group. Therefore, the current control switch BT14 is controlled by the control signal S2 to switch the connection destinations of the switch pair BT17 and the switch pair BT18 according to the polarity of the voltage applied to the terminal pair BT02. The polarity of the voltage applied to the terminal pair BT02 can vary depending on the discharge battery cell group connected to the terminal pair BT01 and the configuration of the transformer circuit BT07. Also, in order to flow a current in the charging direction of the rechargeable battery cell group, it is necessary to connect terminals of the same polarity between the terminal pair BT02 and the rechargeable battery cell group. Therefore, the current control switch BT14 is controlled by the control signal S2 to switch the connection destinations of the switch pair BT17 and the switch pair BT18 according to the polarity of the voltage applied to the terminal pair BT02. The polarity of the voltage applied to the terminal pair BT02 can vary depending on the discharge battery cell group connected to the terminal pair BT01 and the configuration of the transformer circuit BT07. Also, in order to flow a current in the charging direction of the rechargeable battery cell group, it is necessary to connect terminals of the same polarity between the terminal pair BT02 and the rechargeable battery cell group. Therefore, the current control switch BT14 is controlled by the control signal S2 to switch the connection destinations of the switch pair BT17 and the switch pair BT18 according to the polarity of the voltage applied to the terminal pair BT02.

[0257] As an example, a state where a voltage is applied to the terminal pair BT02 such that terminal B1 is the positive electrode and terminal B2 is the negative electrode will be described. At this time, when the lowermost battery cell BT09 of the battery unit BT08 is the rechargeable battery cell group, the switch pair BT17 is controlled by the control signal S2 to be connected to the positive terminal of the battery cell BT09. That is, the switch connected to the bus BT16 of the switch pair BT17 is turned on, and the switch connected to the bus BT15 of the switch pair BT17 is turned off. On the other hand, the switch pair BT18 is controlled by the control signal S2 to be connected to the negative terminal of the battery cell BT09. That is, the s As an example, a state where a voltage is applied to the terminal pair BT02 such that terminal B1 is the positive electrode and terminal B2 is the negative electrode will be described. At this time, when the lowermost battery cell BT09 of the battery unit BT08 is the rechargeable battery cell group, the switch pair BT17 is controlled by the control signal S2 to be connected to the positive terminal of the battery cell BT09. That is, the switch connected to the bus BT16 of the switch pair BT17 is turned on, and the switch connected to the bus BT15 of the switch pair BT17 is turned off. On the other hand, the switch pair BT18 is controlled by the control signal S2 to be connected to the negative terminal of the battery cell BT09. That is, the s As an example, a state where a voltage is applied to the terminal pair BT02 such that terminal B1 is the positive electrode and terminal B2 is the negative electrode will be described. At this time, when the lowermost battery cell BT09 of the battery unit BT08 is the rechargeable battery cell group, the switch pair BT17 is controlled by the control signal S2 to be connected to the positive terminal of the battery cell BT09. That is, the switch connected to the bus BT16 of the switch pair BT17 is turned on, and the switch connected to the bus BT15 of the switch pair BT17 is turned off. On the other hand, the switch pair BT18 is controlled by the control signal S2 to be connected to the negative terminal of the battery cell BT09. That is, the s As an example, a state where a voltage is applied to the terminal pair BT02 such that terminal B1 is the positive electrode and terminal B2 is the negative electrode will be described. At this time, when the lowermost battery cell BT09 of the battery unit BT08 is the rechargeable battery cell group, the switch pair BT17 is controlled by the control signal S2 to be connected to the positive terminal of the battery cell BT09. That is, the switch connected to the bus BT16 of the switch pair BT17 is turned on, and the switch connected to the bus BT15 of the switch pair BT17 is turned off. On the other hand, the switch pair BT18 is controlled by the control signal S2 to be connected to the negative terminal of the battery cell BT09. That is, the s As an example, a state where a voltage is applied to the terminal pair BT02 such that terminal B1 is the positive electrode and terminal B2 is the negative electrode will be described. At this time, when the lowermost battery cell BT09 of the battery unit BT08 is the rechargeable battery cell group, the switch pair BT17 is controlled by the control signal S2 to be connected to the positive terminal of the battery cell BT09. That is, the switch connected to the bus BT16 of the switch pair BT17 is turned on, and the switch connected to the bus BT15 of the switch pair BT17 is turned off. On the other hand, the switch pair BT18 is controlled by the control signal S2 to be connected to the negative terminal of the battery cell BT09. That is, the s As an example, a state where a voltage is applied to the terminal pair BT02 such that terminal B1 is the positive electrode and terminal B2 is the negative electrode will be described. At this time, when the lowermost battery cell BT09 of the battery unit BT08 is the rechargeable battery cell group, the switch pair BT17 is controlled by the control signal S2 to be connected to the positive terminal of the battery cell BT09. That is, the switch connected to the bus BT16 of the switch pair BT17 is turned on, and the switch connected to the bus BT15 of the switch pair BT17 is turned off. On the other hand, the switch pair BT18 is controlled by the control signal S2 to be connected to the negative terminal of the battery cell BT09. That is, the s As an example, a state where a voltage is applied to the terminal pair BT02 such that terminal B1 is the positive electrode and terminal B2 is the negative electrode will be described. At this time, when the lowermost battery cell BT09 of the battery unit BT08 is the rechargeable battery cell group, the switch pair BT17 is controlled by the control signal S2 to be connected to the positive terminal of the battery cell BT09. That is, the switch connected to the bus BT16 of the switch pair BT17 is turned on, and the switch connected to the bus BT15 of the switch pair BT17 is turned off. On the other hand, the switch pair BT18 is controlled by the control signal S2 to be connected to the negative terminal of the battery cell BT09. That is, the s The switch connected to bus BT15 of pair BT18 becomes on, and the switch connected to bus BT16 of pair BT18 becomes off. In this way, terminals with the same polarity are connected between terminal pair BT02 and the rechargeable battery cell group. And the direction of the current flowing from terminal pair BT02 is controlled to be the direction for charging the rechargeable battery cell group.

[0258] Also, current control switch BT14 may be included in switching circuit BT04 instead of switching circuit BT05. In this case, by controlling the polarity of the voltage applied to terminal pair BT01 according to current control switch BT14 and control signal S1, the polarity of the voltage applied to terminal pair BT02 is controlled. And current control switch BT14 controls the direction of the current flowing from terminal pair BT02 to the rechargeable battery cell group.

[0259] FIG. 25 is a circuit diagram showing a configuration example of switching circuit BT04 and switching circuit BT05 different from that of FIG. 24.

[0260] In FIG. 25, switching circuit BT04 has a plurality of transistor pairs BT21, bus BT24, and bus BT25. Bus BT24 is connected to terminal A1. Also, bus BT25 is connected to terminal A2. One end of each of the plurality of transistor pairs BT21 branches into transistor BT22 and transistor BT23, respectively. One of the source or drain of transistor BT22 is connected to bus BT24. Also, one of the source or drain of transistor BT23 is connected to bus BT25. Also, the other ends of the plurality of transistor pairs are each connected between two adjacent battery cells BT09. ​​​​​​​​​​​​​​​ is present. Among the plurality of transistor pairs BT21, the transistor located at the most upstream The other end of the pair BT21 is connected to the positive terminal of the battery cell BT09 located at the most upstream of the battery unit BT08 is connected. Also, among the plurality of transistor pairs BT21, the transistor pair BT21 located at the most downstream The other end of is connected to the negative terminal of the battery cell BT09 located at the most downstream of the battery unit BT08 terminal.

[0261] The switching circuit BT04 switches the conduction / non-conduction states of the transistor BT22 and the transistor BT23, thereby switching the connection destination of the transistor pair BT21 to either the terminal A1 or the terminal A2. Specifically, if the transistor B T22 is in the conduction state, the transistor BT23 is in the non-conduction state, and its connection destination is the terminal A1. On the other hand, if the transistor BT23 is in the conduction state, the transistor BT22 is in the non-conduction state, and its connection destination is the terminal A2. Whether the transistor BT22 or the transistor BT23 is in the conduction state is determined by the control signal S1.

[0262] To connect the terminal pair BT01 and the discharge battery cell group, two transistor pairs BT21 are used Specifically, based on the control signal S1, by determining the connection destinations of the two transistor pairs BT21 respectively, the discharge battery cell group and the terminal pair BT01 are connected. The connection destinations of the two transistor pairs BT21 are controlled by the control signal S1 such that one becomes the terminal A1 and the other becomes the terminal A2.

[0263] The switching circuit BT05 includes a plurality of transistor pairs BT31, a bus BT34, and a bus BT ​​It has 35. The bus BT34 is connected to the terminal B1. Also, the bus BT35 is connected to the terminal B2. One end of each of the plurality of transistor pairs BT31 branches into a transistor BT32 and a transistor BT33. One end branched by the transistor BT32 is connected to the bus BT34. Also, one end branched by the transistor BT33 is connected to the bus BT35. Also, the other ends of the plurality of transistor pairs BT31 are respectively connected between two adjacent battery cells BT09. Among the plurality of transistor pairs BT31, the other end of the transistor pair BT31 located at the uppermost stream is connected to the positive terminal of the battery cell BT09 located at the uppermost stream of the battery unit BT08. Also .

[0264] The switching circuit BT05 switches the conduction / non-conduction states of the transistor BT32 and the transistor BT33 according to the control signal S2, and switches the connection destination of the transistor pair BT31 to either the terminal B1 or the terminal B2. Specifically, if the transistor BT32 is in the conductive state, the transistor BT33 is in the non-conductive state, and its connection destination becomes the terminal B1. Conversely, if the transistor BT33 is in the conductive state, the transistor BT32 is in the non-conductive state, and its connection destination becomes the terminal B2. Which of the transistor BT32 and the transistor BT33 becomes in the conductive state is determined by

[0265] the control signal S2.To connect the terminal pair BT02 and the rechargeable battery cell group, two transistor pairs BT31 are used. Specifically, based on the control signal S2, the connection destinations of the two transistor pairs BT31 are determined respectively, whereby the rechargeable battery cell group and the terminal pair BT02 are connected. The connection destination of each of the two transistor pairs BT31 is controlled by the control signal S2 such that one becomes terminal B1 and the other becomes terminal B2.

[0266] Also, the connection destination of each of the two transistor pairs BT31 is determined by the polarity of the voltage applied to the terminal pair BT02. Specifically, when a voltage such that terminal B1 is the positive electrode and terminal B2 is the negative electrode is applied to the terminal pair BT02, the upstream transistor pair BT31 is controlled by the control signal S2 such that transistor BT32 is in the conducting state and transistor BT33 is in the non-conducting state. On the other hand, the downstream transistor pair BT31 is controlled by the control signal S2 such that transistor BT33 is in the conducting state and transistor BT32 is in the non-conducting state. When a voltage such that terminal B1 is the negative electrode and terminal B2 is the positive electrode is applied to the terminal pair BT02, the upstream transistor pair BT31 is controlled by the control signal S2 such that transistor BT33 is in the conducting state and transistor BT32 is in the non-conducting state. On the other hand, the downstream transistor pair BT31 is controlled by the control signal S2 such that transistor BT32 is in the conducting state and transistor BT33 is in the non-conducting state. In this way, terminals with the same polarity are connected between the terminal pair BT02 and the rechargeable battery cell group. And the direction of the current flowing from the terminal pair BT02 is controlled to be the direction for charging the rechargeable battery cell group. ​​​​​​​​​​​​​​​​

[0267] The voltage conversion control circuit BT06 controls the operation of the voltage conversion circuit BT07. The voltage conversion control circuit BT06 generates a voltage conversion signal S3 for controlling the operation of the voltage conversion circuit BT07 based on the number of battery cells BT09 included in the discharge battery cell group and the number of battery cells BT09 included in the charge battery cell group, and outputs it to the voltage conversion circuit BT07.

[0268] Incidentally, when the number of battery cells BT09 included in the discharge battery cell group is larger than the number of battery cells BT09 included in the charge battery cell group, it is necessary to prevent an excessively large charging voltage from being applied to the charge battery cell group. Therefore, the voltage conversion control circuit BT06 outputs a voltage conversion signal S3 for controlling the voltage conversion circuit BT07 to step down the discharge voltage (Vdis) within a range where the charge battery cell group can be charged.

[0269] Also, when the number of battery cells BT09 included in the discharge battery cell group is less than or equal to the number of battery cells BT09 included in the charge battery cell group, it is necessary to ensure the charging voltage required to charge the charge battery cell group. Therefore, the voltage conversion control circuit BT06 outputs a voltage conversion signal S3 for controlling the voltage conversion circuit BT 07 to step up the discharge voltage (Vdis) within a range where an excessive charging voltage is not applied to the charge battery cell group.

[0270] Incidentally, the voltage value for the excessive charging voltage can be determined in view of product specifications and the like of the battery cell BT09 used in the battery unit BT08. Also, the voltage stepped up and down by the voltage conversion circuit BT07 is applied to the terminal pair BT02 as the charging voltage (Vcha).

[0271] Here, an operation example of the voltage conversion control circuit BT06 in the present embodiment will be described with reference to FIGS. 26(A) to (C).​​​​​​​ will be used for the explanation. FIGS. 26(A) to (C) illustrate the operation example of the voltage conversion control circuit BT06 corresponding to the discharge battery cell group and the rechargeable battery cell group. It is a conceptual diagram for this purpose. Note that FIGS. 26(A) to (C) illustrate the battery control unit BT41. The battery control unit BT41 is composed of the terminal pair BT01, the terminal pair BT02, the switching control circuit BT03, the switching circuit BT04, the switching circuit BT05, the voltage conversion control circuit BT06, and the voltage conversion circuit BT07, as described above. In the example shown in FIG. 26(A), as described in FIG. 23(A), three consecutive high-voltage cells a to c and one low-voltage cell d are connected in series. In this case, as described with reference to FIG. 23(A), the switching control circuit BT03 determines the high-voltage cells a to c as the discharge battery cell group and the low-voltage cell d as the rechargeable battery cell group. Then, the voltage conversion control circuit BT06 calculates the step-up / step-down ratio N of the discharge voltage (Vdis) based on the ratio of the number of battery cells BT09 included in the rechargeable battery cell group to the number of battery cells BT09 included in the discharge battery cell group when the number of battery cells BT09 included in the discharge battery cell group is used as a reference.

[0272] When the number of battery cells BT09 included in the discharge battery cell group is larger than the number of battery cells BT09 included in the rechargeable battery cell group, if the discharge voltage is directly applied to the terminal pair BT02 without voltage conversion, an excessive voltage may be applied to the battery cells BT09 included in the rechargeable battery cell group via the terminal pair BT02. Therefore, in the case shown in FIG. 26(A), it is necessary to step down the charging voltage (Vcha) applied to the terminal pair BT02 to be lower than the discharge voltage.

[0273] ​​​​​​​​​​There is a need. Further, in order to charge the rechargeable battery cell group, the charging voltage needs to be greater than the total voltage of the battery cells BT09 included in the rechargeable battery cell group. Therefore, the buck-boost control circuit B T06 sets the buck-boost ratio N to be larger than the ratio of the number of battery cells BT09 included in the charging battery cell group with respect to the number of battery cells BT09 included in the discharge battery cell group based on the number of battery cells BT09 included in the discharge battery cell group. The buck-boost control circuit BT06 sets the buck-boost ratio N to be larger than the ratio of the number of battery cells BT09 included in the charging battery cell group with respect to the number of battery cells BT09 included in the discharge battery cell group based on the number of battery cells BT09 included in the discharge battery cell group. It is preferably increased by about 1 to 10%. At this time, the charging voltage becomes larger than the voltage of the rechargeable battery cell group, but actually the charging voltage becomes equal to the voltage of the rechargeable battery cell group. However, the buck-boost control circuit BT06 makes the voltage of the rechargeable battery cell group equal to the charging voltage according to the buck-boost ratio N,

[0274] so that a current for charging the rechargeable battery cell group flows. This current becomes the value set in the buck-boost control circuit BT0 6. In the example shown in FIG. 26(A), since the number of battery cells BT09 included in the discharge battery cell group is 3 and the number of battery cells BT09 included in the rechargeable battery cell group is 1, the buck-boost control circuit BT06 calculates a value slightly larger than 1 / 3 as the buck-boost ratio N. Then, the buck-boost control circuit BT06 steps down the discharge voltage according to the buck-boost ratio N and outputs a buck-boost signal S3 for converting it into a charging voltage to the buck-boost circuit BT07. Then, the buck-boost circuit BT07 applies the charging voltage transformed according to the buck-boost signal S3 to the terminal pair BT02. And the battery cells BT09 included in the rechargeable battery cell group are charged by the charging voltage applied to the terminal pair BT02.

[0275] In the example shown in FIG. 26(A), since the number of battery cells BT09 included in the discharge battery cell group is 3 and the number of battery cells BT09 included in the rechargeable battery cell group is 1, the buck-boost control circuit BT06 calculates a value slightly larger than 1 / 3 as the buck-boost ratio N. Then, the buck-boost control circuit BT06 steps down the discharge voltage according to the buck-boost ratio N and outputs a buck-boost signal S3 for converting it into a charging voltage to the buck-boost circuit BT07. Then, the buck-boost circuit BT07 applies the charging voltage transformed according to the buck-boost signal S3 to the terminal pair BT02. And the battery cells BT09 included in the rechargeable battery cell group are charged by the charging voltage applied to the terminal pair BT02. In the example shown in FIG. 26(A), since the number of battery cells BT09 included in the discharge battery cell group is 3 and the number of battery cells BT09 included in the rechargeable battery cell group is 1, the buck-boost control circuit

[0276] Also, in the examples shown in FIGS. 26(B) and 26(C) as well, similar to FIG. 26(A), the step-up / step-down ratio N is calculated. In the examples shown in FIGS. 26(B) and 26(C), the number of battery cells BT09 included in the discharge battery cell group is less than or equal to the number of battery cells BT09 included in the rechargeable battery cell group Therefore, the step-up / step-down ratio N is 1 or more. Thus, in this case, the transformer control circuit BT06 outputs a transformer signal S3 that boosts the discharge voltage and converts it into a power reception voltage.

[0277] Based on the transformer signal S3, the transformer circuit BT07 converts the discharge voltage applied to the terminal pair BT01 into a charging voltage. Then, the transformer circuit BT07 applies the converted charging voltage to the terminal pair BT0 2. Here, the transformer circuit BT07 electrically insulates between the terminal pair BT01 and the terminal pair BT02 This prevents a short circuit due to the difference in the absolute voltage of the negative terminal of the battery cell BT09 located at the lowest position in the discharge battery cell group and the absolute voltage of the negative terminal of the battery cell BT09 located at the lowest position in the rechargeable battery cell group. Furthermore as described above, the transformer circuit BT07 converts the discharge voltage, which is the total voltage of the discharge battery cell group, into a charging voltage based on the transformer signal S3.

[0278] Also, the transformer circuit BT07 can use, for example, an isolated DC (Direct Current)-DC converter or the like. In this case, the transformer control circuit BT06 controls the charging voltage converted by the transformer circuit BT07 by outputting a signal for controlling the on / off ratio (duty ratio) of the isolated DC-DC converter as the transformer signal S3.

[0279] Note that for the isolated DC-DC converter, there are the flyback method, the forward method, the RCC ( There are methods such as the Ringing Choke Converter method, the push-pull method, the half-bridge method, and the full-bridge method, etc. An appropriate method is selected according to the magnitude of the target output voltage. Although there are methods such as the Ringing Choke Converter method, the push-pull method, the half-bridge method, and the full-bridge method, etc., an appropriate method is selected according to the magnitude of the target output voltage. Although there are methods such as the Ringing Choke Converter method, the push-pull method, the half-bridge method, and the full-bridge method, etc., an appropriate method is selected according to the magnitude of the target output voltage.

[0280] The configuration of the transformer circuit BT07 using an isolated DC-DC converter is shown in FIG. 27. The isolated DC-DC converter BT51 has a switch section BT52 and a transformer section BT53. The isolated DC-DC converter BT51 has a switch section BT52 and a transformer section BT53. The switch section BT52 is a switch that switches the on / off operation of the isolated DC-DC converter. For example, it is realized using a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) or a bipolar transistor, etc. The switch section BT52 is a switch that switches the on / off operation of the isolated DC-DC converter. For example, it is realized using a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) or a bipolar transistor, etc. The switch section BT52 is a switch that switches the on / off operation of the isolated DC-DC converter. For example, it is realized using a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) or a bipolar transistor, etc. The switch section BT52 is a switch that switches the on / off operation of the isolated DC-DC converter. For example, it is realized using a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) or a bipolar transistor, etc. The switch section BT52 periodically switches between the on state and the off state of the isolated DC-DC converter BT51 based on a transformer signal S3 that controls the on / off ratio and is output from the voltage conversion control circuit BT06. The switch section BT52 periodically switches between the on state and the off state of the isolated DC-DC converter BT51 based on a transformer signal S3 that controls the on / off ratio and is output from the voltage conversion control circuit BT06. The switch section BT52 can have various configurations depending on the method of the isolated DC-DC converter used. The transformer section BT53 converts the discharge voltage applied from the terminal pair BT01 into a charging voltage. Specifically, The transformer section BT53 operates in conjunction with the on / off state of the switch section BT52 and converts the discharge voltage into a charging voltage according to its on / off ratio. This charging voltage increases as the time in the on state is longer during the switching period of the switch section BT52. On the other hand, This charging voltage decreases as the time in the on state is shorter during the switching period of the switch section BT52. This charging voltage decreases as the time in the on state is shorter during the switching period of the switch section BT52. When using an isolated DC-DC converter, the terminal pair BT01 and the terminal pair BT02 can be insulated from each other inside the transformer section BT53. When using an isolated DC-DC converter, the terminal pair BT01 and the terminal pair BT02 can be insulated from each other inside the transformer section BT53.

[0281] The flow of the processing of the storage battery BT00 in the present embodiment will be described with reference to FIG. 28. FIG. 28 is a flowchart showing the flow of the processing of the storage battery BT00.

[0282] First, the storage battery BT00 acquires the voltages measured for each of the plurality of battery cells BT09 (step S001). Then, the storage battery BT00 determines whether or not the start condition for the operation of equalizing the voltages of the plurality of battery cells BT09 is satisfied (step S002). This start condition can be, for example , whether or not the difference between the maximum value and the minimum value of the voltages measured for each of the plurality of battery cells BT09 is equal to or greater than a predetermined threshold value , etc. If this start condition is not satisfied (step S002 : NO), since the voltages of the respective battery cells BT09 are balanced, the storage battery B T00 does not execute the subsequent processing. On the other hand, if the start condition is satisfied (step S002 : YES), the storage battery BT00 executes the processing of equalizing the voltages of the respective battery cells BT09. In this processing, the storage battery BT00 determines whether each battery cell B T09 is a high-voltage cell or a low-voltage cell based on the measured voltage of each cell (step S003). Then, the storage battery B T00 determines a discharge battery cell group and a charge battery cell group based on the determination result (step S004). Further, the storage battery BT00 generates a control signal S1 for setting the determined discharge battery cell group to the connection destination of the terminal pair BT01 and a control signal S2 for setting the determined charge battery cell group to the connection destination of the terminal pair BT02 (step S005). The storage battery BT00 outputs the generated control signal S1 and control signal S2 to the switching circuit BT04 and the switching circuit BT0 5, respectively. Then, by the switching circuit BT04, the terminal pair BT01 and the discharge electricity are connected to the switching circuit BT04, and the terminal pair BT01 and the discharge electricity are connected to the switching circuit BT04, and the terminal pair BT01 and the discharge electricity The battery cell group is connected, and the switching circuit BT05 connects the terminal pair BT02 and the discharge battery cell group (step S006). Also, the storage battery BT00 generates a voltage conversion signal S3 based on the number of battery cells BT09 included in the discharge battery cell group and the number of battery cells BT09 included in the rechargeable battery cell group (step S007). Then, based on the voltage conversion signal S3, the storage battery BT00 converts the discharge voltage applied to the terminal pair BT01 into a charging voltage and applies it to the terminal pair BT02 (step S008). As a result, the charge of the discharge battery cell group is transferred to the rechargeable battery cell group. Based on the number of battery cells BT09 included in the discharge battery cell group and the number of battery cells BT09 included in the rechargeable battery cell group, a voltage conversion signal S3 is generated (step S007). Then, based on the voltage conversion signal S3, the storage battery BT00 converts the discharge voltage applied to the terminal pair BT01 into a charging voltage and applies it to the terminal pair BT02 (step S008). As a result, the charge of the discharge battery cell group is transferred to the rechargeable battery cell group. Based on the voltage conversion signal S3, the storage battery BT00 converts the discharge voltage applied to the terminal pair BT01 into a charging voltage and applies it to the terminal pair BT02 (step S008). As a result, the charge of the discharge battery cell group is transferred to the rechargeable battery cell group. As a result, the charge of the discharge battery cell group is transferred to the rechargeable battery cell group. As a result, the charge of the discharge battery cell group is transferred to the rechargeable battery cell group.

[0283] Also, in the flowchart of FIG. 28, although a plurality of steps are described in order, the execution order of each step is not limited to the described order. Although a plurality of steps are described in order in the flowchart of FIG. 28, the execution order of each step is not limited to the described order.

[0284] As described above, according to the present embodiment, when transferring charge from the discharge battery cell group to the rechargeable battery cell group, a configuration such as a capacitor method, which temporarily stores the charge from the discharge battery cell group and then discharges it to the rechargeable battery cell group, is not required. Thereby, the charge transfer efficiency per unit time can be improved. Also, the discharge battery cell group and the rechargeable battery cell group can be individually switched by the switching circuit BT04 and the switching circuit BT05. a configuration such as a capacitor method, which temporarily stores the charge from the discharge battery cell group and then discharges it to the rechargeable battery cell group, is not required. Thereby, the charge transfer efficiency per unit time can be improved. Also, the discharge battery cell group and the rechargeable battery cell group can be individually switched by the switching circuit BT04 and the switching circuit BT05. a configuration such as a capacitor method, which temporarily stores the charge from the discharge battery cell group and then discharges it to the rechargeable battery cell group, is not required. Thereby, the charge transfer efficiency per unit time can be improved. Also, the discharge battery cell group and the rechargeable battery cell group can be individually switched by the switching circuit BT04 and the switching circuit BT05. a configuration such as a capacitor method, which temporarily stores the charge from the discharge battery cell group and then discharges it to the rechargeable battery cell group, is not required. Thereby, the charge transfer efficiency per unit time can be improved. Also, the discharge battery cell group and the rechargeable battery cell group can be individually switched by the switching circuit BT04 and the switching circuit BT05.

[0285] Furthermore, based on the number of battery cells BT09 included in the discharge battery cell group and the number of battery cell groups BT09 included in the rechargeable battery cell group, the voltage conversion circuit BT07 converts the discharge voltage applied to the terminal pair BT01 into a charging voltage and applies it to the terminal pair BT02. As a result, regardless of how the battery cells BT09 on the discharge side and the recharge side are selected, charge transfer can be achieved without problems. Based on the number of battery cells BT09 included in the discharge battery cell group and the number of battery cell groups BT09 included in the rechargeable battery cell group, the voltage conversion circuit BT07 converts the discharge voltage applied to the terminal pair BT01 into a charging voltage and applies it to the terminal pair BT02. As a result, regardless of how the battery cells BT09 on the discharge side and the recharge side are selected, charge transfer can be achieved without problems. regardless of how the battery cells BT09 on the discharge side and the recharge side are selected, charge transfer can be achieved without problems. regardless of how the battery cells BT09 on the discharge side and the recharge side are selected, charge transfer can be achieved without problems.

[0286] Furthermore, by using OS transistors for transistor BT10 and transistor BT13, the amount of charge leaking from battery cell BT09, which does not belong to the rechargeable battery cell group or the discharge battery cell group, can be reduced. As a result, a decrease in the capacity of battery cell BT09 that does not contribute to charging and discharging can be suppressed. Also, the OS transistor has less variation in characteristics with respect to heat compared to an Si transistor. Thus, even when the temperature of battery cell BT09 rises, normal operations such as switching between a conductive state and a non-conductive state according to control signals S1 and S2 can be achieved. Note that the present embodiment can be implemented in appropriate combination with other embodiments.

[0287]

[0288] (Embodiment 4) ≪Another Structural Example of the Storage Battery≫

[0289] FIG. 29 shows a storage battery 2100 according to an aspect of the present invention. Three sides of the exterior body 2107 of the storage battery are sealed. Also, it has a positive electrode lead 2121, a negative electrode lead 2125, a positive electrode 2111, a negative electrode 2115, and a separator 2103. Note that, since the figure would become complicated, each electrode is shown as a single layer, but at least some of the electrodes have two or more current collectors, and the current collectors are in contact with each other on surfaces where no active material is formed. Here, with reference to FIG. 30, a part of the method for manufacturing the storage battery 2100 shown in FIG. 29 will be described.

[0290]

[0291] First, the negative electrode 2115 is disposed on the separator 2103 (FIG. 30(A)). At this time, the negative ​​​​​​​​Arrange the negative electrode active material layer of the pole 2115 so as to overlap with the separator 2103.

[0292] Next, fold the separator 2103 and place the separator 2103 on top of the negative electrode 2113. . Next, place the positive electrode 2111 on top of the separator 2103 (Fig. 30(B)). At this time , arrange the positive electrode active material layer 2102 of the positive electrode 2111 so as to overlap with the separator 2103 and the negative electrode active material layer 2106. When using an electrode in which an active material layer is formed on one side of the current collector , arrange the positive electrode active material layer 102 of the positive electrode 2111 and the negative electrode active material layer 2106 of the negative electrode 2115 so as to face each other with the separator 2103 in between.

[0293] When using a material such as polypropylene that can be thermally welded to the separator 2103, by thermally welding the region where the separators 2103 overlap and then stacking the next electrode, it is possible to prevent the electrodes from shifting during the manufacturing process. Specifically, it is preferable to thermally weld the region that does not overlap with the negative electrode 2115 or the positive electrode 2111 and where the separators 2103 overlap, for example, the region indicated by the region 2103a in Fig. 30(B).

[0294] By repeating this process, as shown in Fig. 30(C), the positive electrode 2111 and the negative electrode 2115 can be stacked with the separator 2103 in between.

[0295] Note that a plurality of negative electrodes 2115 and a plurality of positive electrodes 2111 may be alternately arranged so as to sandwich the repeatedly folded separator 2103 in advance.

[0296] Next, as shown in Fig. 30(C), cover the plurality of positive electrodes 2111 and the plurality of negative electrodes 2115 with the separator 2103.

[0297] Furthermore, as shown in FIG. 30(D), by thermally welding the regions where the separators 2103 overlap each other, for example, the region 2103b shown in FIG. 30(D), the plurality of positive electrodes 2111 and the plurality of negative electrodes 2115 are covered and bundled by the separator 2103.

[0298] Note that the plurality of positive electrodes 2111, the plurality of negative electrodes 2115, and the separator 2103 may be bundled using a bundling material.

[0299] In order to stack the positive electrode 2111 and the negative electrode 2115 in such a process, the separator 210 3 has, within a single separator 2103, a region sandwiched between the plurality of positive electrodes 2111 and the plurality of negative electrodes 2115, and a region arranged to cover the plurality of positive electrodes 2111 and the plurality of negative electrodes 2115.

[0300] In other words, the separator 2103 included in the storage battery 2100 of FIG. 29 is a single separator that is partially folded. The plurality of positive electrodes 2111 and the plurality of negative electrodes 2115 are sandwiched in the folded region of the separator 2103.

[0301] Regarding the bonding region of the exterior body 2107 of the storage battery 2100, and the shapes of the positive electrode 2111, the negative electrode 2115, the separator 2103, and the exterior body 2107, and the shapes and positions of the positive electrode lead 2121 and the negative electrode lead 2 125, the description in Embodiment 1 can be referred to. Also, for the method of manufacturing the storage battery 2100d other than the process of stacking the positive electrode 2111 and the negative electrode 2115, the manufacturing method described in Embodiment 1 can be referred to.

[0302] ​​​​​​​FIG. 31 shows a storage battery 100e different from that of FIG. 29. FIG. 31(A) is a perspective view of the storage battery 2200, and FIG. 31(B) is a top view of the storage battery 2200. FIG. 31(C1) is a cross-sectional view of the first electrode assembly 2130, and FIG. 31(C2) is a cross-sectional view of the second electrode assembly 2131. FIG. 31(D) is a cross-sectional view taken along the dash-dotted line H1-H2 in FIG. 31(B). In FIG. 31(D), for clarity, the first electrode assembly 2130, the electrode assembly 2131, and the separator 2 103 are shown in an extracted manner. Also, since the figure would become complicated, each electrode is shown as a single layer, but at least some of the electrodes have two or more current collectors, and the current collectors are in contact with each other on the surfaces where no active material is formed.

[0303] The storage battery 2200 shown in FIG. 31 has an arrangement of the positive electrode 2111 and the negative electrode 2115, and an arrangement of the separator 2103 different from that of the storage battery 2100 in FIG. 29.

[0304] As shown in FIG. 31(D), the storage battery 2200 has a plurality of first electrode assemblies 2130 and a plurality of electrode assemblies 2131.

[0305] As shown in FIG. 31(C1), in the first electrode assembly 2130, a positive electrode 2111a having a positive electrode active material layer 2102 on both sides of a positive electrode current collector 2101, a separator 2103, a negative electrode 2115a having a negative electrode active material layer 2106 on both sides of a negative electrode current collector 2 105, a separator 2103, and a positive electrode 2111a having a positive electrode active material layer 2102 on both sides of the positive electrode current collector 2101 are laminated in this order. Also, as shown in FIG. 31(C2), in the second electrode assembly 2131, a negative electrode 2115a having a negative electrode active material layer 2106 on both sides of a negative electrode current collector 2105, a separator 210 3, a positive electrode 2111a having a positive electrode active material layer 2102 on both sides of a positive electrode current collector 2101, and a separator 210 3 are laminated in this order. electrode 2105, a separator 210 3, a positive electrode 2111a having a positive electrode active material layer 2102 on both sides of a positive electrode current collector 2101, and a separator 210 A negative electrode 2115 having a negative electrode active material layer 2106 on both sides of a separator 2103 and a negative electrode current collector 2105 are laminated in this order.

[0306] Furthermore, as shown in FIG. 31(D), a plurality of first electrode assemblies 2130 and a plurality of second electrode assemblies 2131 are covered by a wound separator 2103.

[0307] Here, using FIG. 32, a part of the method for manufacturing the storage battery 2200 shown in FIG. 31 will be described. .

[0308] First, a first electrode assembly 2130 is disposed on a separator 2103 (FIG. 32(A)).

[0309] Next, the separator 2103 is bent and the separator 21 03 is overlapped on the first electrode assembly 2130. Next, above and below the first electrode assembly 2130, via the separator 2103 , two sets of second electrode assemblies 2131 are overlapped (FIG. 32(B)).

[0310] Next, the separator 2103 is wound so as to cover the two sets of second electrode assemblies 2131. . Furthermore, above and below the two sets of second electrode assemblies 2131, via the separator 2103, two sets of first electrode assemblies 2130 are overlapped (FIG. 32(C)).

[0311] Next, the separator 2103 is wound so as to cover the two sets of first electrode assemblies 2130. (FIG. 32(D)).

[0312] In such a process, a plurality of first electrode assemblies 2130 and a plurality of electrode assemblies 2131 are stacked and overlapped, so these electrode assemblies are disposed between the separators 2103 wound in a spiral shape.

[0313] In addition, it is preferable that the positive electrode 2111a of the outermost electrode assembly 2130 does not have a positive electrode active material layer on the outside.

[0314] Also, in FIGS. 32(C1) and (C2), the electrode assembly having three electrodes and two separators is shown, but one aspect of the present invention is not limited to this. The configuration may have four or more electrodes and three or more separators. By increasing the number of electrodes, the capacity of the storage battery 2200 can be further improved. Also, the configuration may have two electrodes and one separator. When the number of electrodes is small, the storage battery 2200 can be made more resistant to bending. Also, in FIG. 32(D), the storage battery 2200 having three sets of the first electrode assemblies 2130 and two sets of the second electrode assemblies 2131 is shown, but one aspect of the present invention is not limited to this. The configuration may have an even larger number of electrode assemblies. By increasing the number of electrode assemblies, the capacity of the storage battery 2200 can be further improved. Also, the configuration may have fewer electrode assemblies. When the number of electrode assemblies is small, the storage battery 2200 can be made more resistant to bending.

[0315] Regarding the arrangement of the positive electrode 2111 and the negative electrode 2115 of the storage battery 2200 and the arrangement of the separator 2103, reference can be made to the description of FIG. 29.

[0316] This embodiment can be implemented in appropriate combination with other embodiments.

Explanation of Signs

[0317] 100a laminate 100b laminate 100c laminate 100d laminate 101 negative electrode current collector ​​​​​​​​​​​102 Negative electrode active material layer 103 Separator 104 Positive electrode active material layer 105 Positive electrode current collector 107 Electrolyte 110 Lithium-ion battery 115 Lead electrode 116 Exterior body 117 Internal structure 118 Void 300 Battery 301 Positive electrode can 302 Negative electrode can 303 Gasket 304 Positive electrode 305 Positive electrode current collector 306 Positive electrode active material layer 307 Negative electrode 308 Negative electrode current collector 309 Negative electrode active material layer 310 Separator 400 Battery 402 Positive electrode 404 Negative electrode 500 Battery 501 Positive electrode current collector 502 Positive electrode active material layer 503 Positive electrode 504 Negative electrode current collector 505 Negative electrode active material layer 506 Negative electrode 507 Separator 508 Electrolyte 509 Exterior body 510 Positive electrode tab electrode 511 Negative electrode tab electrode 515 Tab electrode 516 Tab electrode 600 Battery 601 Positive electrode cap 602 Battery can 603 Positive electrode terminal 604 Positive electrode 605 Separator 606 Negative electrode 607 Negative electrode terminal 608 Insulating plate 609 Insulating plate 610 Gasket 611 PTC element 612 Safety valve mechanism 900 Circuit board 910 Label 911 Terminal 912 Circuit 913 Battery 914 Antenna 915 Antenna 916 Layer 917 Layer 918 Antenna 919 Terminal 920 Display device 921 Sensor 922 Terminal 930 Housing 930a Housing 930b Housing 931 Negative electrode 932 Positive electrode 933 Separator 951 Terminal 952 Terminal 1101 Center of curvature 1102 End portion on the side closer to the center of curvature of the internal structure 1103 End portion on the side farther from the center of curvature of the internal structure 1104 End portion on the side closer to the center of curvature of the internal structure 1105 End portion on the side farther from the center of curvature of the internal structure 1106 Point on the side closer to the center of curvature of the internal structure 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 Electrode, electrolyte, etc. 2100 Battery 2101 Positive current collector 2102 Positive electrode active material layer 2103 Separator 2103a Region 2103b Region 2105 Negative electrode current collector 2106 Negative electrode active material layer 2107 Outer package 2111 Positive electrode 2111a Positive electrode 2115 Negative electrode 2115a Negative electrode 2121 Positive electrode lead 2125 Negative electrode lead 2130 First electrode assembly 2131 Second electrode assembly 2200 Storage battery 7100 Portable display device 7101 Housing 7102 Display unit 7103 Operation button 7104 Storage battery 7400 Mobile phone 7401 Housing 7402 Display unit 7403 Operation button 7404 External connection port 7405 Speaker 7406 Microphone 7407 Storage battery 8021 Charging device 8022 Cable 8024 Storage battery 8100 Automobile 8101 Headlight S1 Control signal S2 Control signal S3 Transformed signal BT00 Storage battery BT01 Terminal pair BT02 Terminal pair BT03 Switching control circuit BT04 Switching circuit BT05 Switching circuit BT06 Transformer control circuit BT07 Transformer circuit BT08 Battery Unit BT09 Battery Cell BT10 Transistor BT11 Bus BT12 Bus BT13 Transistor BT14 Current Control Switch BT15 Bus BT16 Bus BT17 Switch Pair BT18 Switch Pair BT21 Transistor Pair BT22 Transistor BT23 Transistor BT24 Bus BT25 Bus BT31 Transistor Pair BT32 Transistor BT33 Transistor BT34 Bus BT35 Bus BT41 Battery Control Unit BT51 Isolated DC-DC Converter BT52 Switch Unit BT53 Transformer Unit S001 Step S002 Step S003 Step S004 Step S005 Step S006 Step S007 Step S008 Step

Claims

1. The device has an internal structure and an exterior body, The internal structure has at least a first laminate and a second laminate, the first laminate has a first current collector, the second laminate has a second current collector, a surface of the first current collector having a first region on which no electrode active material is formed; the surface of the second current collector has a second region on which no electrode active material is formed, The exterior body encases the internal structure, At least a portion of the first region is in contact with at least a portion of the second region.

2. The device has an internal structure and an exterior body, The internal structure has at least a first laminate and a second laminate, the first laminate has a first current collector, the second laminate has a second current collector, a surface of the first current collector having a first region on which no electrode active material is formed; the surface of the second current collector has a second region on which no electrode active material is formed, The exterior body encloses the internal structure and the gap, At least a portion of the first region is in contact with at least a portion of the second region; The first stack and the second stack can slide against each other, A flexible lithium ion storage battery, wherein the sliding allows the internal structure to occupy at least a portion of the gap.

3. The device has an internal structure and an exterior body, The internal structure has at least a first laminate and a second laminate, the first laminate has a first current collector, the second laminate has a second current collector, a surface of the first current collector having a first region on which no electrode active material is formed; the surface of the second current collector has a second region on which no electrode active material is formed, The exterior body encloses the internal structure and the gap, At least a portion of the first region is in contact with at least a portion of the second region; By sliding, the internal structure can occupy at least a part of the area of ​​the gap; the internal structure is deformable about a first axis; The void is a flexible lithium ion storage battery, wherein the length A of the outer edge of the cross-sectional shape in a plane perpendicular to the first axis satisfies formula (1). [0010] (In formula (1), L represents the length of the cross-sectional shape of the internal structure in a plane perpendicular to the first axis, T represents the thickness of the cross-sectional shape of the internal structure in the plane, and r ２ represents the distance from the surface of the internal structure farthest from the first axis to the first axis.)

4. In any one of claims 1 to 3, Further, a flexible lithium-ion storage battery having an electrolyte.

5. In claim 2 or 3, Further, the electrolytic solution is included, A flexible lithium ion storage battery, wherein the void can be occupied by the electrolyte.

6. In any one of claims 1 to 5, the first current collector is a positive electrode current collector, The second current collector is a positive electrode current collector.

7. In any one of claims 1 to 5, the first current collector is a negative electrode current collector, The second current collector is a negative electrode current collector.

8. A flexible lithium ion storage battery according to any one of claims 1 to 7; A display and An electronic device having an operation button.

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