JP2022062150A - Lithium ion battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable and flexible lithium ion storage battery or an electronic apparatus.

SOLUTION: A flexible lithium ion storage battery 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. A surface of the first current collector has a first region where no electrode active material is formed, and a surface of the second current collector has a second region where no electrode active material is formed. The exterior body wraps around the internal structure. At least part of the first region is in contact with at least part of the second region. In the current collector, a surface on which no electrode active material is formed has a small coefficient of friction. Therefore, when facing a similar surface, the surface slides according to deformation of the storage battery and can alleviate stress. In addition, a gap may be provided in the interior of the storage battery in order to correspond to various deformation.

SELECTED DRAWING: Figure 5

COPYRIGHT: (C)2022,JPO&INPIT

Description

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

It should be noted that one aspect of the present invention is not limited to the above technical fields. The technical field of one aspect of the invention disclosed in the present specification and the like relates to a product, a method, or a manufacturing method. Alternatively, one aspect of the invention is a process, machine, manufacture, or composition (composition.
Of Matter). Therefore, as the technical field of one aspect of the present invention disclosed more specifically in the present specification, a semiconductor device, a display device, a liquid crystal display device, a light emitting device, a lighting device, a storage battery, a storage device, a method for driving them, or a method thereof. , Those manufacturing methods, can be mentioned as an example.

In recent years, various storage batteries such as storage batteries such as lithium ion storage batteries, lithium ion capacitors, air batteries, and fuel cells have been actively developed. In particular, lithium-ion storage batteries with high output and high energy density include mobile information terminals such as mobile phones, smartphones, and notebook personal computers, electronic devices such as portable music players and digital cameras, medical devices, and hybrid electric vehicles (HEVs). Electric vehicle (EV) or plug-in hybrid vehicle (P)
Demand for next-generation clean energy vehicles such as HEVs, stationary storage batteries, etc. is rapidly expanding with the development of the semiconductor industry and increasing demands for energy saving, and it has become indispensable to modern society. Further, in recent years, expectations for flexible devices or wearable devices have been increasing, and there is an urgent need to develop a flexible lithium-ion storage battery that can be deformed according to the deformation of the device, that is, a flexible storage battery. , Partially started (Patent Document 1).

The lithium ion storage battery has a positive electrode, a negative electrode, a separator, an electrolytic solution, and an exterior body covering them. Generally, in a lithium ion storage battery, a positive electrode having a positive electrode mixture containing a positive electrode active material that absorbs 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 current collector made of copper or the like. A negative electrode coated with a negative electrode mixture containing a negative electrode active material that absorbs and releases lithium ions is used on both sides of the body. Further, the positive electrode and the negative electrode are insulated by sandwiching the separator between the positive electrode and the negative electrode, and the positive electrode and the negative electrode are electrically connected to the positive electrode terminal and the negative electrode terminal provided on the exterior body. The exterior body has a certain shape such as a cylinder or a polygon.

Japanese Unexamined Patent Publication No. 2004-241250

When the flexible lithium-ion storage battery is a laminated lithium-ion storage battery, the stress applied to the storage battery due to deformation differs in each part of the laminated structure. For example, when a laminated lithium-ion storage battery is deformed so as to wind a certain shaft, the laminated structure inside the storage battery is subjected to compressive stress in a portion near the shaft and tensile stress in a portion far from the shaft. Join.

When the structure inside the storage battery is integrated in this way, there is no room for stress generated in each part due to the deformation of the storage battery, and when the deformation of the storage battery is repeated, the internal laminated structure eventually becomes fatigued (
Damage) may accumulate and lead to destruction.

In addition, fatigue (damage) is accumulated not only in the internal laminated structure but also in each member of the battery and the exterior body holding the electrolytic solution as the number of times of deformation of the storage battery increases. Further, since the state of deformation of the internal structure and the state of deformation of the exterior body are different, for example, the deformation stress may be applied to the internal structure beyond the degree of deformation of the internal structure that the exterior body can tolerate. In this case, the internal structure directly applies stress to the exterior body, and fatigue (damage) is accumulated in the exterior body. As the accumulation of fatigue (damage) progresses, the exterior body or the sealing structure may eventually be destroyed, causing a problem that air enters the inside of the storage battery.

If the lithium-ion storage battery is damaged and air enters the inside, the internal members of the storage battery may become moisture in the air or generate heat to ignite, which may lead to a serious accident such as an explosion.

In view of the above, one of the problems of the present invention is to provide a flexible storage battery in which damage to the exterior body due to deformation is suppressed. Alternatively, one of the problems is to provide a storage battery in which damage to the internal structure due to deformation is suppressed. Alternatively, one of the problems is to provide a storage battery having an exterior body capable of allowing deformation of the internal structure. Alternatively, one of the issues is to ensure the safety of the flexible storage battery.

Further, one aspect of the present invention is to provide a flexible and highly safe lithium ion storage battery or an electronic device. Alternatively, one aspect of the present invention is to provide a new lithium ion storage battery, a new electronic device, or the like.

The description of these issues does not preclude the existence of other issues. It should be noted that one aspect of the present invention does not need to solve all of these problems. Issues other than these are self-evident from the description of the description, drawings, claims, etc., and it is possible to extract problems other than these from the description of the specification, drawings, claims, etc. Is.

One aspect of the present invention includes an internal structure and an exterior body, and the internal structure includes a first laminated body and the like.
The second laminated body has at least a second laminated body, the first laminated body has a first current collector, and the second laminated body has a second current collector and has a first current collector. The surface of the electric body is the first one on which the electrode active material is not formed.
The surface of the second current collector has a second region in which the electrode active material is not formed, and the exterior body encloses the internal structure and is at least a part of the first region. Is a flexible lithium-ion storage battery that is in contact with at least a portion of the second region.

Further, another aspect of the present invention includes an internal structure and an exterior body, and the internal structure has at least a first laminated body and a second laminated body, and the first. The laminated body of the above has a first current collector and
The second laminated body has a second current collector, and the surface of the first current collector has a first region in which the electrode active material is not formed, and the surface of the second collector has a second collector. The surface has a second region on which the electrode active material is not formed, the exterior body encloses the internal structure and the voids, and at least a part of the first region is.
It is in contact with at least a part of the second region, and the first laminated body and the second laminated body can slide with each other, and by sliding, the internal structure becomes at least a part of the void. A flexible lithium-ion battery that can occupy an area.

Further, one aspect of the present invention includes an internal structure and an exterior body, and the internal structure has at least a first laminated body and a second laminated body, and the first laminated body. The body has a first collector and a second
The laminated body of the above has a second current collector, the surface of the first current collector has a first region in which the electrode active material is not formed, and the surface of the second current collector is. The exterior has a second region on which the electrode active material is not formed, the exterior body encloses the internal structure and the voids, and at least a part of the first region is the second region.
It is in contact with at least a part of the region, and by sliding, the internal structure can occupy at least a part of the space, and the internal structure can be deformed about the first axis. In the void, the length A of the outer edge of the cross-sectional shape on the plane perpendicular to the first axis satisfies the formula (1).
It is a flexible lithium-ion storage battery.

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

In one aspect of the present invention, a flexible lithium ion storage battery having an electrolytic solution may be further used. Further, in one aspect of the present invention, the electrolytic solution is further provided, and the voids are formed.
It may be a flexible lithium ion storage battery that can be occupied by the electrolytic solution. Further, 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, which may be a flexible lithium ion storage battery. Further, 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, which may be a flexible lithium ion storage battery.

Further, a flexible lithium ion storage battery according to one aspect of the present invention, a display, and the like.
It may be an electronic device having an operation button.

One aspect of the present invention can provide a flexible storage battery in which damage to the exterior body due to deformation is suppressed. Alternatively, it is possible to provide a storage battery in which damage to the internal structure due to deformation is suppressed. Alternatively, it is possible to provide a storage battery having an exterior body that can tolerate deformation of the internal structure. Alternatively, it is possible to ensure safety in a flexible storage battery.

Further, one aspect of the present invention can provide a highly safe lithium ion storage battery or an electronic device having flexibility. Alternatively, one aspect of the present invention can provide a new lithium ion storage battery, a new electronic device, or the like.

The description of these issues does not preclude the existence of other issues. It should be noted that one aspect of the present invention does not need to solve all of these problems. Issues other than these are self-evident from the description of the description, drawings, claims, etc., and it is possible to extract problems other than these from the description of the specification, drawings, claims, etc. Is.

The figure explaining the lithium ion storage battery. The figure explaining the cross-sectional structure of a lithium ion storage battery. The figure explaining the cross-sectional structure of the internal structure of a lithium ion storage battery. The figure explaining the lithium ion storage battery and its cross-sectional structure. The figure explaining the cross-sectional structure of a lithium ion storage battery and the cross-sectional structure in a deformed state. The figure explaining the cross-sectional shape of an internal structure. The figure explaining the radius of curvature. The figure explaining the radius of curvature. The figure explaining the coin type storage battery. The figure explaining the cylindrical storage battery. The figure explaining the laminated type storage battery. The figure which shows the appearance of a storage battery. The figure which shows the appearance of a storage battery. The figure for demonstrating the manufacturing method of a storage battery. The figure explaining the laminated type storage battery which has flexibility. The figure for demonstrating the example of a storage battery. The figure for demonstrating the example of a storage battery. The figure for demonstrating the example of a storage battery. The figure for demonstrating the example of a storage battery. The figure for demonstrating the example of a storage battery. The figure which shows the application form of the storage battery. The block diagram explaining one aspect of this invention. The conceptual diagram explaining one aspect of this invention. A circuit diagram illustrating one aspect of the present invention. A circuit diagram illustrating one aspect of the present invention. The conceptual diagram explaining one aspect of this invention. The block diagram explaining one aspect of this invention. The flowchart explaining one aspect of this invention. A perspective view, a top view, and a sectional view illustrating an example of the configuration of the storage battery. The figure explaining the example of the manufacturing method of the storage battery. A perspective view, a top view, and a sectional view illustrating an example of the configuration of the storage battery. The figure explaining the example of the manufacturing method of the storage battery.

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 is easily understood by those skilled in the art that the form and details thereof can be changed in various ways. Further, the present invention is not limited to the description of the embodiments shown below.

In each of the figures described in the present specification, the size of each component such as the size and thickness of the positive electrode, the negative electrode, the active material layer, the separator, the exterior body, etc. is exaggerated individually for the purpose of clarifying the explanation. May have been. Therefore, each component is not necessarily limited to its size, nor is it limited to the relative size between the components.

Further, in the present specification and the like, the ordinal numbers attached as the first, second, third and the like are used for convenience and do not indicate the order of processes or the positional relationship between the upper and lower parts. Therefore, for example, the "first" can be appropriately replaced with the "second" or "third" for explanation.
In addition, the ordinal numbers described in the present specification and the like may not match the ordinal numbers used to specify one aspect of the present invention.

Further, in the configuration of the present invention described in the present specification and the like, the same reference numerals are commonly used between different drawings for the same parts or parts having similar functions, and the repeated description thereof will be omitted. Further, when referring to a portion having the same function, the hatch pattern may be the same and no particular reference numeral may be added.

Further, as used herein, the term "flexibility" refers to the property that an object is flexible and can bend. It is a property that an object can be deformed according to an external force applied to the object, and it does not matter whether or not there is elasticity or resilience to the shape before deformation. A flexible storage battery can be deformed in response to an external force. The flexible storage battery can be fixedly used in a deformed state, may be repeatedly deformed and used, or may be used in a non-deformed state.
Further, in the present specification and the like, the inside of the exterior body refers to the region surrounded by the exterior body in the lithium ion storage battery, and the positive electrode, the negative electrode, the active material layer, the structure such as the separator, the electrolytic solution and the like are present. Area to do.

In addition, the contents described in the embodiment for carrying out the present invention can be used in combination as appropriate.

(Embodiment 1)
In the present embodiment, the lithium ion storage battery 110 according to one aspect of the present invention and a method for manufacturing the lithium ion storage battery 110 will be described.

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

FIG. 2 is a cross-sectional view and an enlarged view thereof when the lithium ion storage battery 110 according to one aspect of the present invention is cut by A1-A2 of FIG. As shown in FIG. 2, the lithium ion storage battery 110 described in the present embodiment has the electrolytic solution 107 and the internal structure 117 as a first laminated body 100a, a second laminated body 100b, and a third laminated body 100c. , The fourth laminated body 100d. The number of laminates included in the lithium ion storage battery 110 described in the present embodiment is mainly 4, but is not limited to this. 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.

Further, in the lithium ion storage battery 110 described in the present embodiment, as shown in the enlarged view of FIG. 2, the first laminated body 100a to the fourth laminated body 100d have the same laminated structure, but each laminated body. In the body, the stacking order of the constituent layers is alternately reversed.
However, the laminated bodies are not limited to having the same laminated structure.

In the lithium ion storage battery 110 described in the present embodiment, the first laminated body 1 is used.
The surface of the positive electrode current collector of 00a on which the active material is not formed is in contact with the surface of the second laminated body 100b on which the active material of the positive electrode current collector is not formed. The surface on which the active material of the negative electrode current collector is not formed is in contact with the surface on which the active material of the negative electrode current collector of the third laminated body 100c is not formed, and the negative electrode collection of the third laminated body 100c. The surface on which the active material of the electric body is not formed is in contact with the surface on which the active material of the negative electrode current collector of the fourth laminated body 100d is not formed. However, in the lithium ion storage battery 110 according to one aspect of the present invention, it is not limited that all the laminated bodies are in contact with each other.

Since each current collector is a thin-film member made of a metal material as described later, its surface is extremely flat and its coefficient of friction is small. However, on the surface where the active material layer is formed on the surface, in general, the surface of the current collector on which the active material is not formed has a shape having larger unevenness.
The coefficient of friction becomes large, and depending on the composition of the material forming the active material layer, adhesiveness may be exhibited to the structure in contact with the surface.

That is, since the current collector and the separator are laminated via the active material layer inside each laminated body, the friction between the respective layers is large, and all the structures constituting the laminated body are treated as one. It is possible, and the layers do not separate from each other unless a certain amount of force is applied from the outside. On the other hand, since the surfaces of the current collectors are in contact with each other and the surface of each current collector has a small coefficient of friction, the laminated bodies can easily slide with each other in response to an external force. ..

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

FIG. 3A shows a cross-sectional view of the internal structure of the laminated lithium ion storage battery 110 before deformation. 3 (B) and 3 (C) show cross-sectional views of the internal structure of the laminated lithium ion storage battery 110 in a deformed state. 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 addition, in FIG. 3, 100a
To 100d indicate each laminated body. In FIG. 3, the number of laminated bodies is 4, but the number of laminated bodies is not limited to this.

First, FIG. 3B is a diagram showing a case where the friction between the laminated bodies is large, and even if the lithium ion storage battery 110 is deformed, sliding does not occur between the laminated bodies and the lithium ion storage battery 110 is deformed as a unit. In addition, FIG. 3 (
D) is an enlarged view of a part of FIG. 3 (B). It represents a case where the friction between the laminated bodies is large and the sliding between the laminated bodies does not occur due to the deformation. Due to the deformation, tensile stress is generated in some laminated bodies, while compressive stress is generated in another laminated body, so that each laminated body is subjected to different stresses. It cannot be resolved.

When the magnitude of deformation exceeds the limit, the difference in stress applied to each laminated body becomes too large, and irreversible peeling occurs between each laminated body. Alternatively, the stress applied to each layer constituting each laminated body becomes too large, so that each layer is damaged (damaged) such as cracks and breaks. Even if the magnitude of the deformation does not exceed the limit, if the deformation is repeated many times, the accumulation of damage due to stress also causes such a problem. In any case, it becomes a serious problem for the function of the lithium ion storage battery 110, and the state cannot withstand further use.

On the other hand, FIG. 3C is a diagram showing a case where the friction between the laminated bodies is small because, for example, the laminated bodies are in contact with each other on the surfaces where the active material of the current collector is not formed. Is. Further, FIG. 3 (E) is an enlarged view of a part of FIG. 3 (C). When the friction between the laminates is small, the stress applied to each laminate according to the deformation of the lithium ion storage battery 110 is relieved by sliding between the laminates.

Therefore, even if the lithium ion storage battery 110 is greatly deformed, the generated stress is relaxed by sliding, so that peeling is unlikely to occur between the laminated bodies. Alternatively, since the stress applied to each layer constituting each laminated body is also relaxed, the damage given to each layer is reduced and cracks and breaks are less likely to occur. Furthermore, even when many deformations are repeated, the structure is such that the stress is easily relaxed, so that the accumulation of damage is small.

The lithium ion storage battery according to one aspect of the present invention has a small friction between each laminated body, and each laminated body can slide with each other according to the deformation of the storage battery. Become. Alternatively, 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.

By the way, in the lithium ion storage battery according to one aspect of the present invention, the laminated bodies can slide with each other and damage due to deformation is suppressed, but they cannot be deformed endlessly. This is because if the amount of deformation of the storage battery is increased, another problem will occur.

The problem will be described with reference to FIGS. 4 and 5. 4 (A) shows the lithium ion storage battery 110 according to one aspect of the present invention, and FIG. 4 (B) shows the cross-sectional structure of the broken line B1-B2 of FIG. 4 (A). In the lithium ion storage battery according to one aspect of the present invention,
Although each laminated body can slide with each other, since the storage battery has a lead electrode 115 for supplying electric power to the outside and the lead electrode 115 is connected to a plurality of current collectors, each laminated body Is preferably fixed to each other at the end on the side where the lead electrode 115 is present. If the end is not fixed, different amounts of sliding will occur in each laminated body when the storage battery is deformed, so the magnitude of sliding on the lead electrode 115 to which the current collector of each laminated body is connected. This is because stress is generated due to the difference between the two.

FIG. 5 shows a change in the cross-sectional shape of the lithium ion storage battery 110 in which the laminated bodies are fixed to each other at one end due to deformation. First, FIG. 5A is a diagram showing a cross-sectional structure of a lithium ion storage battery before deformation. In this figure, the number of laminated bodies is 4, but the number of laminated bodies is not limited to 4 in the lithium ion storage battery according to one aspect of the present invention. As shown in FIG. 5A, the exterior body can be made larger than the size sufficient to enclose all the inner laminated bodies. By providing the void 118 (actually, the area occupied by the electrolytic solution) inside the storage battery in this way, there is room for the exterior body and the laminate to slide with each other, and the exterior body and the laminate can be expected. It is possible to prevent the damage from occurring.

FIG. 5B shows a cross-sectional structure of the modified lithium ion storage battery 110. Lead electrode 11
On the side with 5, the laminates are fixed to each other, while in the other parts
Since each laminated body slides on each other, it has a cross-sectional structure shown in FIG. 5 (B). Here, FIG. 5 (B)
As can be understood from the above, as the degree of deformation of the lithium ion storage battery increases, the void (region occupied by the electrolytic solution) 118 inside the storage battery becomes smaller due to the change in the cross-sectional shape thereof. Further, when the storage battery is to be deformed more than shown in FIG. 5 (B), the voids are exhausted and interference occurs with the exterior body, and eventually the laminated body stresses the exterior body or the exterior body or the exterior body. The laminate may be damaged. Therefore, the void 11 according to the size of the deformation assumed in the storage battery
It is desirable to provide 8 inside the storage battery.

On the other hand, if the void 118 is made excessively large, a volume increase that is not directly related to the capacity of the storage battery occurs, and the capacity value per volume of the storage battery decreases, which is a problem.

The voids are provided by making the length of the exterior body in the cross section shown in FIG. 5A greater than or equal to the length required to cover the internal structure. From the assumed magnitude of deformation given to the storage battery, the size of the void required to continue covering the internal structure without interference can be derived, and it is necessary to provide the void of that size. The length of the exterior body can be derived.

Therefore, a lithium ion storage battery having flexibility that can prevent damage to the exterior body due to deformation of the storage battery and suppresses a decrease in capacity per volume due to an increase in voids as much as possible will be described below.

<Shape change of flexible lithium-ion storage battery and setting of voids>
First, the shape change of the flexible lithium ion storage battery will be described. In order to clarify the explanation, FIG. 6 (A) shows a schematic diagram of the outer ring shape of the internal structure of the storage battery (combined all the laminated bodies) in FIG. 5 (A). That is, FIG. 6A is a diagram showing the outer ring shape of the internal structure 117 of the lithium ion storage battery before deformation. Further, FIG. 6 (B) shows a schematic diagram of the outer ring shape of the internal structure 117 of the lithium ion storage battery in FIG. 5 (B). That is, FIG. 6B is a diagram showing the outer ring shape of the internal structure 117 of the deformed lithium ion storage battery 110. In this figure, the end on the side far from the center of curvature 1101 of the internal structure is 1105, the end on the side far from the center of curvature 1101 of the internal structure is 1103 and 1105, respectively, and the end on the side close to the center of curvature of the internal structure. The portions are 1102 and 1104, respectively, and the points on the side closer to the center of curvature of the internal structure are 1106.

In FIG. 6A, the length of the laminated body in the cross section (for example, the length between 1102 and 1104) is L, and the thickness of the internal structure (for example, the length between 1102 and 1103) is T. And. Next, FIG. 6B is a diagram showing a cross-sectional structure of the internal structure 117 of the lithium ion storage battery, which is given a deformation having a size that uses up the voids. In FIG. 6B, the center of curvature 11 of the deformation
Let r ₂ be the distance (radius of the arc) starting from 01 and ending at the end 1103 of the internal structure 117 on the side far from the center of curvature 1101. Further, the distance (radius of the arc) from the center of curvature 1101 to the end 1102 of the internal structure on the _side close to the center of curvature 1101 is set to r1.

First, the perimeter of the outer ring shape of the internal structure 117 in the cross section of FIG. 6 (A) is 2L + 2.
It becomes T. Next, the length of the outer ring shape of the internal structure in the cross section of FIG. 6B will be examined. First, the thickness of the internal structure (the length between 1104 and 1105) at one end where the laminated bodies are fixed to each other does not change before and after the deformation, so that it is T.

Next, the lengths of the portion of the internal structure near the center of curvature (arc between 1102 and 1104) and the portion far from the center of curvature (arc between 1103 and 1105) are also before and after the deformation of the storage battery. Since it does not change with, it becomes L respectively. In the lithium ion storage battery according to one aspect of the present invention, since the laminated bodies can slide with each other, the laminated bodies slide with each other according to the deformation of the storage battery and the stress is relaxed, so that the lengths of both portions are long. Because it doesn't change.

Therefore, the change in the circumference of the outer ring shape of the internal structure 117 due to the deformation of the storage battery can be obtained by examining the length of the remaining portion (between 1102 and 1103). Here, the point 1106 on the side near the center of curvature of the internal structure will be described. The point 1106 is an intersection of a 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 side of the outer ring shape of the internal structure near the center of curvature. Then, since the center of curvature 1101 is also the center of curvature of the arc (the arc between 1102 and 1104) whose shape is closer to the center of curvature of the internal structure, it is far from the arc and the center of curvature of the internal structure. The straight line connecting the side end 1103 and the center of curvature 1101 is orthogonal at the point 1106. Further, the arc between the end portion 1102 and the point 1106 can be approximated by a straight line because the central angle is small. Therefore, when the end 1103, the end 1102, and the point 1106 are connected, a right triangle is formed, so that the end 11
The length between 02 and the end 1103 can be determined by the Pythagorean theorem using the lengths of the other two sides of the triangle.

First, since the length between the point 1106 and the end 1103 is the thickness of the internal structure 117,
It becomes T.

Next, the length between the point 1106 and the end 1102 is 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. Is the length.
Therefore, the length L1 of the arc between the _point 1106 and the end 1104 is examined.

The length of the arc is the product of the diameter and the pi, multiplied by the ratio of the size of the central angle to 360 °. That is, L ₁ is represented by the following equation (2).

Here, r ₁ represents the radius of the arc, which is the shape on the side closer to the center of curvature of the internal structure, and θ represents the central angle of the arc. By the way, the parts of the internal structure far from the center of curvature (1103 and 1105).
_The length of the arc) is L, but since this part is an arc with a central angle of θ and a radius of r2.
Similarly, the following equation (3) holds.

Here, when the equation (3) is applied to the equation (2), the following equation (4) is established.

Therefore, in a right triangle connecting the end 1103, the end 1102, and the point 1106, assuming that the length of the hypotenuse is T ₁ , the following equation (5) holds according to the Pythagorean theorem.

When the equation (4) is applied to the equation (5), the following equation (6) holds for the length of T ₁ .

Further, the radius of the arc of the outer ring shape of the internal structure on the side far from the center of curvature 1101 is r ₂ .
Since the radius of the arc of the outer ring shape of the internal structure near the center of curvature 1101 is r ₁ , and the difference is the thickness T of the internal structure, r ₁ is the value obtained by subtracting T from r ₂ . .. Therefore, the equation (6)
) To T ₁ is expressed by the following equation (7).

In the state before the lithium ion storage battery is deformed, the length between the end portion 1103 and the end portion 1102 is the thickness T of the internal structure. End 1103 and end 110 in the deformed state
Since the length between 2 and 2 is T ₁ , the increase in the length between the end 1103 and the end 1102 due to the deformation of the lithium ion storage battery is T _1-1 , which is expressed by the following equation (8). It will be the expressed value.

That is, it is desirable that a gap sufficient to allow the increase is provided inside the storage battery. In short, in the cross section shown in FIG. 6, the internal length of the exterior body is the length of the outer edge of the internal structure before deformation. It is desirable that the length is 2L + 2T plus T1 _- T, which is the increase due to deformation. In other words, based on the thickness and length of the internal structure, the size of the void for preventing damage to the exterior body of the storage battery can be derived from the radius of curvature desired as the degree of deformation of the storage battery.

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 exterior body on the plane perpendicular to the axis may be set to a length of 2L + T + T ₁ or more, which is the length of the outer ring shape of the internal structure 117 at the time of deformation. Assuming that the length of the exterior body at that time is A, A satisfies the following formula (1).

It should be noted that the technical idea is only in the lithium ion storage battery according to one aspect of the present invention, in which the friction between the laminated bodies is small and the laminated bodies slide with each other and are released from the stress according to the deformation of the storage battery. It also solves existing problems.

Next, the lithium ion storage battery according to one aspect of the present invention will be described.

≪Construction 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.

As the positive electrode active material used for the positive electrode active material layer 104, a material capable of inserting and removing carrier ions such as lithium ions can be used. For example, an olivine type crystal structure and a layered rock salt type crystal structure can be used. , Or a lithium-containing material having a spinel-type crystal structure.

Lithium-containing material with olivine structure (general formula LiMPO ₄ (M is Fe (II), Mn (
Typical examples of II), Co (II) or Ni (II)) are LiFePO ₄ , Li.
NiPO ₄ , LiCoPO ₄ , LiMnPO ₄ , LiFe _a Ni _b PO ₄ , LiFe _a C
_ob PO ₄ , LiFe _a Mn _b PO ₄ , LiNi _a Co _b PO ₄ , LiNi _a Mn _b PO
₄ (a + b is 1 or less, 0 <a <1, 0 < _b <1), LiFe _c Nid _Coe PO ₄ , Li
Fe _c Ni _d Mn _e PO ₄ , LiNi _c Co _d Mn _e PO ₄ (c + d + e is 1 or less, 0 <
c <1, 0 <d <1, 0 <e <1), LiFe _f Ni _g Coh Mn _i PO ₄ (f + g + _h )
+ I has 1 or less, 0 <f <1, 0 <g <1, 0 <h <1, 0 <i <1), and the like.

For example, lithium iron phosphate (LiFePO ₄ ) meets the requirements for a positive electrode active material in a well-balanced manner, such as safety, stability, high volume density, high potential, and the presence of lithium ions that are extracted during initial oxidation (charging). Therefore, it is preferable.

Examples of the lithium-containing material having a layered rock salt type crystal structure include lithium cobalt oxide (LiCoO ₂ ), LiNiO ₂ , LiMnO ₂ , Li ₂ MnO ₃ , and LiNi _0.8 Co.
_0.2 O ₂ etc. NiCo system (general formula is LiNi _x Co _1-x O ₂ (0 <x <1)), L
NiMn system such as iNi _0.5 Mn _0.5 O ₂ (general formula is LiNi _x Mn _1-x O ₂ (0)
<X <1)), NiMnCo system such as LiNi _1/3 Mn _1/3 Co _1/3 O ₂ (also referred to as NMC. The general formula is LiNi _x Mn _y Co _1-x-y O ₂ (x> 0). , Y> 0, x + y <1
)). Furthermore, Li (Ni _0.8 Co _0.15 Al _0.05 ) O ₂ and Li ₂
MnO ₃ -LiMO ₂ (M is Co, Ni or Mn) and the like can also be mentioned.

In particular, LiCoO ₂ is preferable because it has advantages such as a large capacity, stability in the atmosphere as compared with LiNiO ₂ , and thermal stability as compared with LiNiO ₂ .

Examples of the lithium-containing material having a spinel-type crystal structure include LiMn ₂ O ₄ , L.
Examples thereof include i _{1 + x} Mn _2-x O ₄ , Li (MnAl) ₂ O ₄ , LiMn _1.5 Ni _0.5 O ₄ .

For lithium-containing materials having a spinel-type crystal structure containing manganese such as LiMn ₂ O ₄
A small amount of lithium nickelate (LiNiO ₂ or LiNi _1-x MO ₂ (M = Co, Al, etc.))
) Is preferable because it has advantages such as suppressing the elution of manganese and suppressing the decomposition of the electrolytic solution.

Further, as the positive electrode active material, the general formula Li _(2-j) MSiO ₄ (M is Fe (II), Mn.
A composite oxide represented by (II), Co (II), or Ni (II)) (j is 0 or more and 2 or less) can be used. As a typical example of the general formula Li _(2-j) MSiO 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 Core SiO 4, Li (2-j) Fe k Mn l SiO 4 , Li ( 2-j)} Ni _{k Core}
SiO ₄ , Li _(2-j) Nik Mn _l SiO ₄ ( _k + l is 1 or less, 0 <k <1, 0 <l
<1), Li _(2-j) Fe _m Ni _n Co _q SiO ₄ , Li _(2-j) Fe _m Ni _n Mn
_q SiO ₄ , Li _(2-j) Ni _m Con _n Mn _q SiO ₄ (m + n + q is 1 or less, 0 <m
<1, 0 <n <1, 0 <q <1), Li _{(2-j) Ferr Nis Cot Mn u SiO 4} (
Examples of r + s + t + u are 1 or less, 0 <r <1, 0 <s <1, 0 <t <1, 0 <u <1), and the like.

Further, as the positive electrode active material, A _x M ₂ (XO ₄ ) ₃ (A is Li, Na, or Mg) (M).
Can be a Nashicon type compound represented by the general formula of Fe, Mn, Ti, V, Nb, or Al) (X is S, P, Mo, W, As, or Si). Examples of the pear-con type compound include Fe ₂ (MnO ₄ ) ₃ , Fe ₂ (SO ₄ ) ₃ , Li ₃ Fe ₂ (PO ₄ ) ₃ and the like. In addition, as positive electrode active materials, Li ₂ MPO ₄ F, Li ₂ MP ₂ O ₇ , Li ₅ M
Compounds represented by the general formula of O ₄ (M is Fe or Mn), perovskite-type fluorides such as NaFeF ₃ , FeF ₃ , and metal chalcogenides (sulfides, selenes, tellurides) such as TiS ₂ and MoS ₂ . Lithium-containing materials having an inverted spinel-type crystal structure such as LiMVO ₄ , vanadium oxide-based (V ₂ O ₅ , V ₆ O ₁₃ , LiV ₃ O ₈ , etc.), manganese oxide, etc.
Materials such as organic sulfur can be used.

When the carrier ion is an alkali metal ion other than lithium ion or an alkaline earth metal ion, the above compound or oxide may be an alkali metal (for example, sodium or potassium) instead of lithium as a positive electrode active material. , Alkaline earth metals (eg, calcium, strontium, barium, beryllium, magnesium, etc.) may be used. For example, sodium-containing layered oxides such as NaFeO ₂ and Na _2/3 [Fe _1/2 Mn _1/2 ] O ₂ can be used as the positive electrode active material.

Further, as the positive electrode active material, a material obtained by combining a plurality of the above materials may be used. For example, a solid solution in which a plurality of the above materials are combined can be used as a positive electrode active material. For example, Li
A solid solution of Co _1/3 Mn _1/3 Ni _1/3 O ₂ and Li ₂ Mn O ₃ can be used as the positive electrode active material.

As the positive electrode active material, it is preferable to use a positive electrode active material having an average particle size of primary particles of 50 nm or more and 100 μm or less.

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

Since the active material comes into contact with the electrolytic solution, the active material reacts with the electrolytic solution, and when the active material is lost and deteriorates due to the reaction, the capacity of the storage battery decreases. It is desirable that such a reaction does not occur.

As the conductive auxiliary agent for the electrode, acetylene black (AB), graphite particles, carbon nanotubes, graphene, fullerene and the like can be used.

The conductive auxiliary agent can form a network of electrical conduction in the electrodes. The conductive auxiliary agent can maintain the path of electrical conduction between the positive electrode active materials. By adding a conductive auxiliary agent to the positive electrode active material layer, the positive electrode active material layer 101 having high electrical conductivity can be realized.

Further, as the binder, in addition to typical polyvinylidene fluoride (PVDF), polyimide, polytetrafluoroethylene, polyvinyl chloride, ethylene propylene diene polymer, fluororubber, polymethylmethacrylate, polyethylene, nitrocellulose and the like can be used.

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 further preferably 3 wt% or more and 5 wt% or less. Further, the content of the conductive auxiliary agent with respect to the total amount of the positive electrode active material layer 101 is 1 wt%.
10 wt% or more is preferable, and 1 wt% or more and 5 wt% or less is more preferable.

When the positive electrode active material layer 104 is formed by the coating method, the positive electrode active material, the binder, the conductive auxiliary agent, and the dispersion medium are mixed to prepare an electrode slurry, which is applied onto the positive electrode current collector 105 and dried. Just do it.

For the positive electrode current collector 105, a material having high conductivity and not alloying with carrier ions such as lithium can be used, such as metals such as stainless steel, gold, platinum, aluminum and titanium, and alloys thereof. Further, an aluminum alloy to which an element for improving heat resistance such as silicon, titanium, neodymium, scandium, and molybdenum is added can be used. Further, it may be formed of a metal element that reacts with silicon to form silicide. Metallic elements that react with silicon to form silicide include zirconium, titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, nickel and the like. As the positive electrode current collector, a foil-like shape, a plate-like shape (sheet-like shape), a net-like shape, a punching metal-like shape, an expanded metal-like shape, or the like can be appropriately used.

The positive electrode active material layer 104 may be provided on one side of the positive electrode current collector 105, and the positive electrode active material layer may not be provided on the other side. In that case, the surface of the positive electrode current collector 105 is flat and has a small friction coefficient in a state where the positive electrode active material layer is not provided. Therefore, when the surface of another positive electrode current collector on which the positive electrode active material layer is not provided is in contact with the surface, both current collectors can slide with each other depending on the stress.

The positive electrode of the lithium ion storage battery can be manufactured by the above steps.

≪Construction 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 process of forming the negative electrode will be described below.

As the negative electrode active material used for the negative electrode active material layer 102, as carbon-based materials, graphite, easily graphitizable carbon (soft carbon), non-graphitizable carbon (hard carbon), carbon nanotubes, graphene, carbon black and the like are used. be. Examples of graphite include artificial graphite such as mesocarbon microbeads (MCMB), coke-based artificial graphite, and pitch-based artificial graphite, and natural graphite such as spheroidized natural graphite. The shape of graphite includes scaly ones and spherical ones.

As the negative electrode active material, in addition to the carbon-based material, a material capable of performing a charge / discharge reaction by an alloying / dealloying reaction with lithium can also be used. For example, Ga, Si, Al, Ge,
A material containing at least one of Sn, Pb, Sb, Bi, Ag, Zn, Cd, In and the like can be used. Such an element has a larger capacity than carbon, and silicon is particularly preferable because it has a theoretical capacity of 4200 mAh / g. Examples of alloy-based materials using such elements include Mg ₂ Si, Mg ₂ Ge, Mg ₂ Sn, SnS ₂ , V ₂ Sn ₃ , FeSn ₂ , and the like.
CoSn ₂ , Ni ₃ Sn ₂ , Cu ₆ Sn ₅ , Ag ₃ Sn, Ag ₃ Sb, Ni ₂ MnSb,
There are CeSb ₃ , LaSn ₃ , La ₃ Co ₂ Sn ₇ , CoSb ₃ , InSb, SbSn and the like.

Further, as the negative electrode active material, SiO, SnO, SnO ₂ , titanium dioxide (TIO ₂ ), lithium titanium oxide (Li ₄ Ti ₅ O ₁₂ ), lithium-graphite intercalation compound (Li _x C ₆ ),
Niobium pentoxide (Nb ₂ O ₅ ), tungsten oxide (WO ₂ ), molybdenum oxide (MoO ₂ )
) And other oxides can be used.

Further, as the negative electrode active material, Li _{3 -x} M _x N (M is Co, Ni or Cu) having a Li 3N type structure, which is a compound nitride of lithium and a transition metal, 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 preferable.

When lithium and transition metal compound nitrides are used, lithium ions are contained in the negative electrode active material.
As the positive electrode active material, it can be combined with materials such as V ₂ O ₅ and Cr ₃ O ₈ that do not contain lithium ions. Even when a material containing lithium ions is used as the positive electrode active material, a double nitride of lithium and a transition metal can be used as the negative electrode active material by desorbing the lithium ions contained in the positive electrode active material in advance.

Further, a material that causes a conversion reaction can also be used as a negative electrode active material. For example, a transition metal oxide that does not alloy with lithium, such as cobalt oxide (CoO), nickel oxide (NiO), and iron oxide (FeO), may be used as the negative electrode active material. Further, as the material in which the conversion reaction occurs, Fe ₂ O ₃ , CuO, Cu ₂ O, RuO ₂ , Cr ₂ O
Oxides such as ₃ mag, sulfides such as CoS _0.89 , NiS, CuS, Zn ₃ N ₂ , Cu ₃ N, G
Nitrides such as e ₃ N ₄ , phosphides such as NiP ₂ , FeP ₂ , CoP ₃ , FeF ₃ , BiF ₃
It also occurs with fluorides such as.

As an example, the negative electrode active material may have a particle size of 50 nm or more and 100 μm or less.

In both the positive electrode active material layer 104 and the negative electrode active material layer 102, a plurality of materials may be used in combination at a specific ratio. By using a plurality of materials for the active material layer, the performance of the active material layer can be selected in more detail.

As the conductive auxiliary agent for the electrode, acetylene black (AB), graphite particles, carbon nanotubes, graphene, fullerene and the like can be used.

The conductive auxiliary agent can form a network of electrical conduction in the electrodes. The conductive auxiliary agent can maintain the path of electrical conduction between the negative electrode active materials. By adding a conductive auxiliary agent to the negative electrode active material layer, the negative electrode active material layer 102 having high electrical conductivity can be realized.

In addition to typical polyvinylidene fluoride (PVDF), polyimide, polyvinyl chloride, ethylene propylene diene polymer, styrene-butadiene rubber, acrylonitrile-butadiene rubber, fluororubber, polyvinyl acetate, polymethylmethacrylate, polyethylene, etc. Nitrocellulose or the like can be used.

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 further preferably 3 wt% or more and 5 wt% or less. Further, the content of the conductive auxiliary agent with respect to the total amount of the negative electrode active material layer 103 is 1 wt%.
10 wt% or more is preferable, and 1 wt% or more and 5 wt% or less is more preferable.

Next, the negative electrode active material layer 102 is formed on the negative electrode current collector 101. When the negative electrode active material layer 102 is formed by the coating method, the negative electrode active material, the binder, the conductive auxiliary agent, and the dispersion medium are mixed to prepare a slurry, which is applied to the negative electrode current collector 101 and dried. Moreover, you may perform a press process if necessary after drying.

For the negative electrode current collector 101, a material having high conductivity and not alloying with carrier ions such as lithium, such as metals such as stainless steel, gold, platinum, iron, copper, titanium, and tantalum, and alloys thereof, is used. be able to. Further, it may be formed of a metal element that reacts with silicon to form silicide. Metallic elements that react with silicon to form silicide include zirconium, titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, nickel and the like. The negative electrode current collector 102 has a foil shape and a plate shape (sheet shape).
, Net-like, columnar, coil-like, punching metal-like, expanded metal-like, and the like can be appropriately used. The negative electrode current collector 101 having a thickness of 5 μm or more and 30 μm or less may be used. Further, an undercoat layer may be provided on a part of the surface of the electrode current collector by using graphite or the like.

The negative electrode active material layer 102 may be provided on one side of the negative electrode current collector 101, and the negative electrode active material layer may not be provided on the other side. In that case, the surface of the negative electrode current collector 101 is flat and the friction coefficient is small in a state where the negative electrode active material layer is not provided. Therefore, when the surface of another negative electrode current collector that is not provided with the negative electrode active material layer comes into contact with the surface, both current collectors can slide with each other depending on the stress.

The negative electrode of the lithium ion storage battery can be manufactured by the above steps.

≪Construction of separator≫
The separator 103 will be described. As the material of the separator 103, paper, non-woven fabric, glass fiber, synthetic fiber such as nylon (polyamide), vinylon (polyvinyl alcohol-based fiber), polyester, acrylic, polyolefin, polyurethane and the like may be used. However, it is necessary to select a material that does not dissolve in the electrolytic solution described later.

More specifically, as the material of the separator 103, for example, a fluoropolymer, a polyether such as polyethylene oxide and polypropylene oxide, a polyolefin such as polyethylene and polypropylene, polyacrylonitrile, polyvinylidene chloride, polymethylmethacrylate and polymethylacrylate, Polyvinyl alcohol, polymethacrylonitrile,
Polyvinyl acetate, polyvinylpyrrolidone, polyethyleneimine, polybutadiene,
One selected from polystyrene, polyisoprene, polyurethane polymers and derivatives thereof, cellulose, paper, non-woven fabric, and glass fiber can be used alone or in combination of two or more.

The separator 103 must have insulation performance to prevent contact between the two electrodes, performance to hold the electrolytic solution, and ion conductivity. As a method for producing a film having a function as a separator, there is a method by stretching the film. For example, there is a stretch-opening method in which a molten polymer material is developed to dissipate heat, and the obtained film is stretched in a biaxial direction parallel to the film to form holes.

In the above process, the separator can be incorporated into the lithium ion storage battery.

≪Composition of electrolyte≫

The electrolytic solution 107 that can be used in the lithium ion storage 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 electrolytic solution 107, a material in which carrier ions can move is used. For example, an aprotic organic solvent is preferable, and ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate, chloroethylene carbonate, vinylene carbonate, γ-butyrolactone, γ-valerolactone, dimethyl carbonate (DMC), diethyl carbonate (dethyl carbonate) ( DEC), ethylmethyl carbonate (EMC), methyl formate, methyl acetate, methyl butyrate, 1,3-dioxane, 1,4-dioxane, dimethoxyethane (DM)
E), dimethyl sulfoxide, diethyl ether, methyl diglime, acetonitrile,
One of benzonitrile, tetrahydrofuran, sulfolane, sultone and the like, or two or more of them can be used in any combination and ratio.

Further, by using a gelled polymer material as the solvent of the electrolytic solution 107, the safety against liquid leakage and the like is enhanced. In addition, the lithium ion storage battery can be made thinner and lighter. Typical examples of the polymer material to be gelled include silicone gel, acrylic gel, acrylonitrile gel, polyethylene oxide gel, polypropylene oxide gel, and fluoropolymer gel.

Further, by using one or more ionic liquids (also referred to as room temperature molten salts) that are flame-retardant and flame-retardant as the solvent of the electrolytic solution, the internal temperature of the lithium ion storage battery can be increased due to internal short circuit, overcharging, or the like. Even if it rises, it is possible to prevent the lithium-ion storage battery from exploding or catching fire.
As a result, the safety of the lithium ion storage battery can be enhanced.

Further, as the electrolytic solution used for the storage battery, it is preferable to use a highly purified electrolytic solution having a small content of granular dust and elements other than the constituent elements of the electrolytic solution (hereinafter, also simply referred to as “impurities”). Specifically, the mass ratio of impurities to the electrolytic solution is preferably 1% or less, preferably 0.1% or less, and more preferably 0.01% or less. Further, an additive such as vinylene carbonate may be added to the electrolytic solution.

When lithium ion is used as the carrier as the electrolyte to be dissolved in the above solvent, for example, 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 SO ₃ , 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 and the like, or two or more of them can be used in any combination and ratio.

In the above electrolyte, the case where the carrier ion is lithium ion has been described, but carrier ions other than lithium ion can also be used. As carrier ions other than lithium ions, in the case of alkali metal ions and alkaline earth metal ions, as an electrolyte, in the above lithium salt, instead of lithium, an alkali metal (for example, sodium, potassium, etc.) or an alkaline earth metal (for example) For example, calcium, strontium, barium, beryllium, magnesium, etc.) may be used.

The electrolytic solution may react with the positive electrode current collector and corrode the positive electrode current collector. In order to prevent such corrosion, it is preferable to add several wt% LiPF ₆ to the electrolytic solution. This is because a non-conductor film is formed on the surface of the positive electrode current collector, and the non-conductor film suppresses the reaction between the electrolytic solution and the positive electrode current collector. However, in order not to dissolve the positive electrode active material layer, the concentration of LiPF ₆ is preferably 10 wt% or less, preferably 5 wt% or less, and more preferably 3 wt% or less.

≪Structure of exterior body≫
Next, the exterior body 116 will be described. The exterior body 116 is provided with a highly flexible metal thin film such as aluminum, stainless steel, copper, and nickel on a film made of a material such as polyethylene, polypropylene, polycarbonate, ionomer, or polyamide, and further on the metal thin film. A film having a three-layer structure provided with an insulating synthetic resin film such as a polyamide resin or a polyester resin can be used as the outer surface of the exterior body. By having such a three-layer structure, the permeation of the electrolytic solution and the gas is blocked, the insulating property is ensured, and the electrolytic solution resistance is also provided. By bending the exterior bodies inward and stacking them, or by stacking the two exterior bodies facing each other and applying heat, the material on the inner surface can be melted and the two exterior bodies can be fused and sealed. The structure can be made.

Assuming that the place where the outer body is fused and the sealing structure is formed is the sealing part, when the outer body is bent inward and overlapped, the sealing part is formed at the place other than the crease and the outer body The first area and
The structure is such that the first region and the second region overlapping the first region are fused or the like. Further, when two exterior bodies are stacked, a sealing portion is formed on the entire outer periphery by a method such as heat fusion.

In one aspect of the present invention, the exterior body 116 is the lithium ion storage battery 11 as described above.
Since a gap is provided inside 0, it is desirable that the length is a certain length or longer.

≪Flexible storage battery≫
When a flexible material is selected and used from the materials of each member shown in the present embodiment,
A flexible lithium-ion storage battery can be manufactured. In recent years, research and development of deformable devices have been active. As a storage battery used for such a device, there is a demand for a flexible storage battery.

When a storage battery sandwiching 1805 such as an electrode and an electrolytic solution is curved using two films as an exterior body, the radius of curvature 1802 of the film 1801 on the side closer to the center of curvature 1800 of the storage battery is the film on the side far from the center of curvature 1800. It is smaller than the radius of curvature 1804 of 1803 (Fig. 7 (Fig. 7).
A)). When the storage battery is curved to have an arcuate cross section, compressive stress is applied to the surface of the film near the center of curvature 1800, and tensile stress is applied to the surface of the film far from the center of curvature 1800 (FIG. 7 (B)).

When a flexible lithium-ion storage battery is deformed, a large stress is applied to the exterior body, but if a pattern formed by recesses or protrusions is formed on the surface of the exterior body, the deformation of the storage battery causes compressive stress and tensile stress. Even if it is applied, the effect of strain can be suppressed. Therefore, in the storage battery, the radius of curvature of the exterior body near the center of curvature is 50 mm, preferably 30 mm.
It can be transformed within the range of.

The radius of curvature of the surface will be described with reference to FIG. In FIG. 8A, in a plane 1701 obtained by cutting a 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 set as the radius of curvature 1703, and the center of the circle is the curvature. The center is 1704. FIG. 8B shows a top view of the curved surface 1700. FIG. 8C shows a cross-sectional view of a curved surface 1700 cut along a plane 1701. When cutting a curved surface with a plane, the radius of curvature of the curve appearing in the cross section differs depending on the angle of the plane with respect to the curved surface and the cutting position. And.

The cross-sectional shape of the storage battery is not limited to a simple arc shape, and can be a shape having a partial arc shape. For example, the shape shown in FIG. It can also be S-shaped. When the curved surface of the storage battery has a shape having a plurality of centers of curvature, the outer body closer to the center of curvature of the two exterior bodies is the curved surface having the smallest radius of curvature among the radii of curvature at each of the plurality of centers of curvature. The storage battery can be deformed within a range in which the radius of curvature of the above is 50 mm, preferably 30 mm.

≪Battery assembly and aging≫
Next, by combining the above-mentioned components and sealing the exterior body 207, FIGS. 1 and 2
As shown in the above, an electrolytic solution comprises an internal structure having a plurality of laminated bodies in which a positive electrode current collector 105, a positive electrode active material layer 104, a separator 103, a negative electrode active material layer 102, and a negative electrode current collector 101 are stacked. It is in a state of being sealed by the exterior body 107 together with the 107.

Next, an aging step is performed. First, the environmental temperature is maintained at, for example, about room temperature, and constant current charging is performed at a low rate to a matching voltage. Next, the gas generated in the region inside the exterior body due to charging is discharged to the outside of the exterior body. Next, charging is performed at a higher rate than the initial charging.

After that, 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.

After storing for a long time in a slightly high temperature environment, the gas generated in the area inside the exterior body is released again. Further, 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 at the same rate. Then, the aging process is completed by discharging at the same rate.

As described above, the storage battery according to the present invention can be manufactured.

This embodiment can be implemented in combination with other embodiments as appropriate.

In the present specification and the like, when at least one specific example is described in the figure or text described in one embodiment, it is easy for a person skilled in the art to derive a superordinate concept of the specific example. Understood by. Therefore, when at least one specific example is described in the figure or text described in one embodiment, the superordinate concept of the specific example is also disclosed as one aspect of the invention, and one of the inventions. It is possible to construct an embodiment. And it can be said that one aspect of the invention is clear.

In the present specification and the like, at least the contents shown in the figure (may be a part in the figure) are disclosed as one aspect of the invention, and one aspect of the invention can be configured. Is. Therefore, if a certain content is described in the figure, the content is disclosed as one aspect of the invention even if the text is not described, and the content may constitute one aspect of the invention. It is possible. Similarly, a figure obtained by taking out a part of the figure is also disclosed as one aspect of the invention, and it is possible to construct one aspect of the invention. And it can be said that one aspect of the invention is clear.

In the present embodiment, one aspect of the present invention has been described. Alternatively, in another embodiment, one aspect of the present invention will be described. However, one aspect of the present invention is not limited to these. That is, since various aspects of the invention are described in this embodiment and other embodiments, one aspect of the present invention is not limited to a specific aspect. For example, as one aspect of the present invention, an example of application to a flexible lithium ion secondary battery has been shown, but one aspect of the present invention is not limited thereto. In some cases, or depending on the circumstances, one aspect of the invention is various secondary batteries, lead storage batteries, lithium ion polymer secondary batteries, nickel / hydrogen storage batteries, nickel / cadmium storage batteries, nickel / iron storage batteries, nickel. -It may be applied to a zinc storage battery, a silver oxide / zinc storage battery, a solid-state battery, an air battery, a primary battery, a capacitor, an electric double layer capacitor, an ultra capacitor, a super capacitor, a lithium ion capacitor, or the like. Or, for example, in some cases, or depending on the circumstances, one aspect of the invention may not be applicable to a lithium ion secondary battery.

(Embodiment 2)
In the present embodiment, the structure of the 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. 9A is an external view of a coin-type (single-layer flat type) storage battery, and FIG. 9B is a cross-sectional view thereof.

The coin-type storage battery 300 includes a positive electrode can 301 that also serves as a positive electrode terminal and a negative electrode can 3 that also serves as a negative electrode terminal.
02 is 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 with the positive electrode current collector 305. Even if the positive electrode active material layer 306 has, in addition to the positive electrode active material, a binder (binder) for enhancing the adhesion of the positive electrode active material, a conductive auxiliary agent for increasing the conductivity of the positive electrode active material layer, and the like. good.

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 with the negative electrode current collector 308. The negative electrode active material layer 309 may have, in addition to the negative electrode active material, a binder (binder) for enhancing the adhesion of the negative electrode active material, a conductive auxiliary agent for enhancing the conductivity of the negative electrode active material layer, and the like. good. A separator 31 is located between the positive electrode active material layer 306 and the negative electrode active material layer 309.
It has 0 and an electrolyte (not shown).

The material shown in the first embodiment can be used for each component.

For the positive electrode can 301 and the negative electrode can 302, a metal such as nickel or titanium, which is corrosion resistant to an electrolytic solution, or an alloy thereof or an alloy between these and another metal (for example, stainless steel, etc.) shall be used. Can be done. Further, in order to prevent corrosion due to 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.

The negative electrode 307, the positive electrode 304, and the separator 310 are impregnated into the electrolyte, and as shown in FIG. 9B, the positive electrode 304, the separator 310, the negative electrode 307, and the negative electrode can 302 are laminated in this order with the positive electrode can 301 facing down. , The positive electrode can 301 and the negative electrode can 302 are crimped via the gasket 303 to manufacture a coin-shaped storage battery 300.

Here, the current flow during charging of the storage battery will be described with reference to FIG. 9 (C). When a storage battery using lithium is regarded as one closed circuit, the movement of lithium ions and the flow of current are in the same direction. In a storage battery using lithium, the anode (anode) and cathode (cathode) are exchanged by charging and discharging, and the oxidation reaction and reduction reaction are exchanged. Therefore, an electrode having a high reaction potential is called a positive electrode, and the reaction potential is changed. An electrode with a low cathode is called a negative electrode. Therefore, in the present specification,
Regardless of whether it is charging, discharging, flowing a reverse pulse current, or flowing a charging current, the positive electrode is called "positive electrode" or "+ pole (plus pole)". The negative electrode is referred to as "negative electrode" or "-pole (minus pole)". When the terms anode (anode) and cathode (cathode) related to oxidation reaction and reduction reaction are used, the charging and discharging are reversed, which may cause confusion. Therefore, the terms anode (anode) and cathode (cathode) are not used herein. If the terms anode (anode) and cathode (cathode) are used, specify whether they are charging or discharging, and also indicate whether they correspond to the positive electrode (positive electrode) or the negative electrode (negative electrode). do.

A charger is connected to the two terminals shown in FIG. 9C, and the storage battery 400 is charged. As the storage battery 400 is charged, the potential difference between the electrodes increases. In FIG. 9C, the current flows from the external terminal of the storage battery 400 toward the positive electrode 402, flows from the positive electrode 402 toward the negative electrode 404, and flows from the negative electrode toward the external terminal of the storage battery 400 in the storage battery 400. The direction of the current is the positive direction. That is, the direction in which the charging current flows is the direction of the current.

≪Cylindrical storage battery≫
Next, an example of a cylindrical storage battery will be described with reference to FIG. Cylindrical storage battery 60
As shown in FIG. 10A, 0 has a positive electrode cap (battery lid) 601 on the upper surface and a battery can (outer can) 602 on the side surface and the bottom surface. These positive electrode caps and battery cans (exterior cans) 6
02 is insulated by a gasket (insulating packing) 610.

FIG. 10B is a diagram schematically showing a cross section of a cylindrical storage battery. Inside the hollow cylindrical battery can 602, a battery element in which a band-shaped positive electrode 604 and a negative electrode 606 are wound with a separator 605 sandwiched between them is provided. Although not shown, the battery element is wound around the center pin. One end of the battery can 602 is closed and the other end is open. For the battery can 602, a metal such as nickel or titanium having corrosion resistance to an electrolytic solution, or an alloy thereof or an alloy between these and another metal (for example, stainless steel or the like) can be used. Further, in order to prevent corrosion due to 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, the negative electrode, and the separator are wound is a pair of insulating plates 608 facing each other.
It is sandwiched by 609. Further, a non-aqueous electrolytic solution (not shown) is injected into the inside of the battery can 602 provided with the battery element. As the non-aqueous electrolyte solution, the same one as that of a coin-type storage battery can be used.

The positive electrode 604 and the negative electrode 606 may be manufactured in the same manner as the positive electrode and the negative electrode of the coin-shaped storage battery described above. It differs in that it forms. A positive electrode terminal (positive electrode current collecting tab) 603 is connected to the positive electrode 604, and a negative electrode terminal (negative electrode current collecting tab) 607 is connected to the negative electrode 606. A metal material such as aluminum can be used for both the positive electrode terminal 603 and the negative electrode terminal 607. 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 a PTC element (Positive Temperature).
It is electrically connected to the positive electrode cap 601 via a Coefficient) 611. The safety valve mechanism 612 has a positive electrode cap 6 when the increase in the internal pressure of the battery exceeds a predetermined threshold value.
It disconnects the electrical connection between 01 and the positive electrode 604. Further, the PTC element 611 is a heat-sensitive resistance element whose resistance increases when the temperature rises, and the amount of current is limited by the increase in resistance to prevent abnormal heat generation. The PTC element is barium titanate (BaTIO ₃ ).
) System semiconductor ceramics and the like can be used.

≪Laminated storage battery≫
Next, an example of the laminated storage battery will be described with reference to FIG. 11 (A). If the laminated storage battery has a flexible configuration and is mounted on an electronic device having at least a part of the flexible portion, the storage battery can also be bent according to the deformation of the electronic device.

The laminated storage battery 500 shown in FIG. 11A has a positive electrode 503 having a positive electrode current collector 501 and a positive electrode active material layer 502, a negative electrode 506 having a negative electrode current collector 504 and a negative electrode active material layer 505, and a separator 507. And an electrolytic solution 508 and an exterior body 509. A separator 507 is installed between the positive electrode 503 and the negative electrode 506 provided in the exterior body 509. Further, the inside of the exterior body 509 is filled with the electrolytic solution 508. As the electrolytic solution 508, the electrolytic solution shown in the first embodiment can be used.

In the laminated storage battery 500 shown in FIG. 11A, 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 so as to be exposed to the outside from the exterior body 509. Further, the positive electrode current collector 501 and the negative electrode current collector 504 are not exposed to the outside from the exterior body 509, and the tab electrode is ultrasonically bonded to the tab electrode and the positive electrode current collector 501 or the negative electrode current collector 504 using a tab electrode. The tab electrode may be exposed to the outside.

In the laminated storage battery 500, on the exterior body 509, a metal thin film having excellent flexibility such as aluminum, stainless steel, copper, and nickel is formed on a film made of a material such as polyethylene, polypropylene, polycarbonate, ionomer, and polyamide. A three-layered laminated film can be used in which an insulating synthetic resin film such as a polyamide resin or a polyester resin is provided on the metal thin film as the outer surface of the exterior body.

Further, an example of the cross-sectional structure of the laminated storage battery 500 is shown in FIG. 11 (B). FIG. 11 (A
) Shows an example of being composed of two current collectors for the sake of simplicity, but in reality, it is composed of a plurality of electrode layers.

In FIG. 11B, the number of electrode layers is 16 as an example. Even if the number of electrode layers is 16, the storage battery 500 has flexibility. FIG. 11B shows a structure in which the negative electrode current collector 504 has eight layers and the positive electrode current collector 501 has eight layers, for a total of 16 layers. Note that FIG. 11B shows a cross section of the negative electrode extraction portion, in which eight layers of negative electrode current collectors 504 are ultrasonically bonded. Of course,
The number of electrode layers is not limited to 16, and may be large or small. When the number of electrode layers is large, a storage battery having a larger capacity can be used. Further, when the number of electrode layers is small, the storage battery can be made thinner and has excellent flexibility.

Here, an example of an external view of the laminated storage battery 500 is shown in FIGS. 12 and 13. FIG. 12
And FIG. 13 has a positive electrode 503, a negative electrode 506, a separator 507, an exterior body 509, a positive electrode tab electrode 510, and a negative electrode tab electrode 511.

FIG. 14A shows an external view of the positive electrode 503 and the negative electrode 506. The positive electrode 503 is a positive electrode current collector 50.
The positive electrode active material layer 502 is formed on the surface of the positive electrode current collector 501. Further, the positive electrode 503 has a region (referred to as a tab region) in which the positive electrode current collector 501 is partially exposed. Negative electrode 506
Has a negative electrode current collector 504, and the negative electrode active material layer 505 is formed on the surface of the negative electrode current collector 504. Further, the negative electrode 506 has a region where the negative electrode current collector 504 is partially exposed, that is, a tab region. The area and shape of the tab region of the positive electrode and the negative electrode are not limited to the example shown in FIG. 14 (A).

≪How to make a laminated storage battery≫
Here, an example of a method for manufacturing a laminated storage battery whose external view is shown in FIG. 12 is shown in FIG. 14 (
B) and (C) will be described.

First, the negative electrode 506, the separator 507, and the positive electrode 503 are laminated. FIG. 14B shows the negative electrode 506, the separator 507, and the positive electrode 503 laminated. Here, an example in which 5 sets of negative electrodes and 4 sets of positive electrodes are used is shown. Next, the tab regions of the positive electrode 503 are joined to each other, and the positive electrode tab electrode 510 is joined to the tab region of the positive electrode on the outermost surface. For joining, for example, ultrasonic welding may be used. Similarly, the tab regions of the negative electrode 506 are bonded to each other, and the negative electrode tab electrode 511 is bonded to the tab region of the negative electrode on the outermost surface.

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

Next, as shown in FIG. 14C, the exterior body 509 is bent at the portion shown by the broken line. After that, the outer peripheral portion of the exterior body 509 is joined. For example, thermocompression bonding may be used for joining. At this time, a region (hereinafter referred to as an introduction port) that is not joined to a part (or one side) of the exterior body 509 is provided so that the electrolytic solution 508 can be put in later.

Next, the electrolytic solution 508 is introduced into the inside of the exterior body 509 from the introduction port provided in the exterior body 509. The electrolytic solution 508 is preferably introduced under a reduced pressure atmosphere or an inert gas atmosphere. And finally, the inlet is joined. In this way, the storage battery 500, which is a laminated type storage battery, can be manufactured.

In the present embodiment, the coin-type, laminated-type, and cylindrical storage batteries are shown as the storage batteries, but other sealed storage batteries, square storage batteries, and other storage batteries of various shapes can be used. Further, a structure in which a plurality of positive electrodes, negative electrodes, and separators are laminated, and a structure in which positive electrodes, negative electrodes, and separators are wound may be used.

Further, FIG. 10 shows an example of mounting a flexible laminated storage battery in an electronic device. Electronic devices to which storage batteries with flexible shapes are applied include, for example, television devices (also referred to as televisions or television receivers), monitors for computers, digital cameras, digital video cameras, digital photo frames, mobile phones (also referred to as televisions or television receivers). (Also referred to as a mobile phone or a mobile phone device), a portable game machine, a mobile information terminal, a sound reproduction device, a large game machine such as a pachinko machine, and the like.

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

FIG. 15A shows an example of a mobile phone. The mobile phone 7400 has a housing 7401.
In addition to the display unit 7402 built into the unit, it is equipped with an operation button 7403, an external connection port 7404, a speaker 7405, a microphone 7406, and the like. The mobile phone 7400 has a storage battery 7407.

FIG. 15B shows a state in which the mobile phone 7400 is curved. Mobile phone 740
When 0 is deformed by an external force to bend the whole, the storage battery 7 provided inside the 0 is bent.
407 is also curved. Further, the state of the bent storage battery 7407 at that time is shown in FIG. 15 (C). The storage battery 7407 is a laminated type storage battery.

FIG. 15D shows an example of a bangle type display device. The portable display device 7100 is
It includes a housing 7101, a display unit 7102, an operation button 7103, and a storage battery 7104. Further, FIG. 15 (E) shows the state of the bent storage battery 7104.

≪Structural example of storage battery≫
An example of the structure of the storage battery will be described with reference to FIGS. 16 to 20.

16 (A) and 16 (B) are views showing an external view of the storage battery. The storage battery includes a circuit board 900 and a storage battery 913. A label 910 is affixed to the storage battery 913. Further, as shown in FIG. 16B, the storage battery has a terminal 951, a terminal 952, and an antenna 915.

The circuit board 900 has a terminal 911 and a circuit 912. Terminal 911 is terminal 951
, Terminal 952, antenna 914, antenna 915, and 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, or the like.

The circuit 912 may be provided on the back surface of the circuit board 900. The antenna 914 and the antenna 915 are not limited to the coil shape, and may be, for example, a linear shape or a plate shape. also,
Antennas such as a plane antenna, an open surface antenna, a traveling wave antenna, an EH antenna, a magnetic field antenna, and a dielectric antenna may be used. Alternatively, the antenna 914 or the antenna 915 may be a flat conductor. This flat plate-shaped conductor can function as one of the conductors for electric field coupling. That is, the antenna 914 or the antenna 915 may function as one of the two conductors of the capacitor. This makes it possible to exchange electric power not only with an electromagnetic field and a magnetic field but also with an electric field.

The line width of the antenna 914 is preferably larger than the line width of the antenna 915. As a result, the amount of electric power received by the antenna 914 can be increased.

The storage battery has a layer 916 between the antenna 914 and the antenna 915 and the storage battery 913. The layer 916 has a function capable of preventing the influence of the storage battery 913 on the electromagnetic field, for example. As the layer 916, for example, a magnetic material can be used.

The structure of the storage battery is not limited to FIG.

For example, as shown in FIGS. 17 (A-1) and 17 (A-2), FIGS. 16 (A) and 16 (A).
Of the storage batteries 913 shown in (B), antennas may be provided on each of the pair of facing surfaces. FIG. 17 (A-1) is an external view seen from one side of the pair of surfaces, and FIG. 17 (A-1).
-2) is an external view seen from the other side of the pair of surfaces. For the same parts as the storage battery shown in FIGS. 16A and 16B, the description of the storage battery shown in FIGS. 16A and 16B can be appropriately referred to.

As shown in FIG. 17 (A-1), the antenna 914 is provided on one of the pair of surfaces of the storage battery 913 with the layer 916 interposed therebetween, and as shown in FIG. 17 (A-2), the pair of surfaces of the storage battery 913. The antenna 915 is provided on the other side of the antenna 917 with the layer 917 interposed therebetween. The layer 917 has a function of preventing the influence of the storage battery 913 on the electromagnetic field, for example. As the layer 917, for example, a magnetic material can be used.

With the above structure, the sizes of both the antenna 914 and the antenna 915 can be increased.

Alternatively, as shown in FIGS. 17 (B-1) and 17 (B-2), FIGS. 16 (A) and 16 (
Of the storage batteries 913 shown in B), different antennas may be provided on each of the pair of facing surfaces. FIG. 17 (B-1) is an external view seen from one side of the pair of surfaces, and is a view of FIG. 17 (B-1).
B-2) is an external view seen from the other side of the pair of surfaces. For the same parts as the storage battery shown in FIGS. 16A and 16B, the description of the storage battery shown in FIGS. 17A and 17B can be appropriately referred to.

As shown in FIG. 17 (B-1), the antenna 914 and the antenna 915 are provided on one of the pair of surfaces of the storage battery 913 with the layer 916 interposed therebetween, and as shown in FIG. 17 (B-2), the storage battery 91.
An antenna 918 is provided on the other side of the pair of surfaces of 3 with the layer 917 interposed therebetween. The antenna 918 has, for example, a function capable of performing data communication with an external device. For the antenna 918, for example, an antenna having a shape applicable to the antenna 914 and the antenna 915 can be applied. As a communication method between the storage battery and other devices via the antenna 918, a response method that can be used between the storage battery and other devices such as NFC can be applied.

Alternatively, as shown in FIG. 18A, the display device 920 may be provided in the storage battery 913 shown in FIGS. 16A and 16B. The display device 920 is electrically connected to the terminal 911 via the terminal 919. It is not necessary to provide the label 910 in the portion where the display device 920 is provided. The same parts as the storage batteries shown in FIGS. 16 (A) and 16 (B) are shown in FIG.
The description of the storage battery shown in 6 (A) and FIG. 16 (B) can be appropriately incorporated.

The display device 920 may display, for example, an image showing whether or not charging is in progress, an image showing the amount of stored electricity, and the like. As the display device 920, for example, an electronic paper, a liquid crystal display device, an electroluminescence (also referred to as EL) display device, or the like can be used. For example, the power consumption of the display device 920 can be reduced by using electronic paper.

Alternatively, as shown in FIG. 18B, the sensor 921 may be provided in the storage battery 913 shown in FIGS. 16A and 16B. The sensor 921 is electrically connected to the terminal 911 via the terminal 922. For the same parts as the storage battery shown in FIGS. 16A and 16B, the description of the storage battery shown in FIGS. 16A and 16B can be appropriately referred to.

The sensor 921 includes, for example, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, voice, time, hardness, electric field, current, voltage, power, radiation, flow rate. It suffices to have a function capable of measuring humidity, inclination, vibration, odor, or infrared rays. By providing the sensor 921, for example, data indicating the environment in which the storage battery is placed (
It is also possible to detect (temperature, etc.) and store it in the memory in the circuit 912.

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

The storage battery 913 shown in FIG. 19A has a winding body 950 provided with terminals 951 and terminals 952 inside the housing 930. The winding body 950 is impregnated with the 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. 19A, the housing 930 is shown separately for convenience, but in reality, the winding body 950 is covered with the housing 930, and the terminals 951 and 952 are shown.
Extends outside the housing 930. As the housing 930, a metal material or a resin material can be used.

As shown in FIG. 19B, the housing 930 shown in FIG. 19A may be formed of a plurality of materials. For example, the storage battery 913 shown in FIG. 19B has a housing 930a and a housing 93.
0b is bonded to each other, and the winding body 95 is formed in the area surrounded by the housing 930a and the housing 930b.
0 is provided.

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 on which the antenna is formed, it is possible to suppress the shielding of the electric field by the storage battery 913. 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.

Further, the structure of the wound body 950 is shown in FIG. The winding body 950 has a negative electrode 931, a positive electrode 932, and a separator 933. The wound body 950 is a wound body in which the negative electrode 931 and the positive electrode 932 are overlapped and laminated with the separator 933 interposed therebetween, and the laminated sheet is wound. A plurality of layers of the negative electrode 931, the positive electrode 932, and the separator 933 may be further laminated.

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

≪Example of electronic device: Example to be mounted on a vehicle≫
Next, an example of mounting the storage battery in the 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.

FIG. 16 illustrates a vehicle using one aspect of the present invention. Vehicle 8 shown in FIG. 21 (A)
Reference numeral 100 is an electric vehicle that uses an electric motor as a power source for traveling. or,
It is a hybrid vehicle that can be used by appropriately selecting an electric motor and an engine as a power source for driving. By using one aspect of the present invention, it is possible to realize a vehicle that can be repeatedly charged and discharged. Further, the automobile 8100 has a storage battery. The storage battery can not only drive an electric motor but also supply electric power to a light emitting device such as a headlight 8101 or a room light (not shown).

Further, the storage battery can supply electric power to display devices such as a speedometer and a tachometer included in the automobile 8100. Further, the storage battery can supply electric power to a semiconductor device such as a navigation system included in the automobile 8100.

The automobile 8100 shown in FIG. 21B can be charged by receiving electric power from an external charging facility by a plug-in method, a non-contact power supply method, or the like to the storage battery of the automobile 8100. FIG. 21B shows a state in which the storage battery mounted on the automobile 8100 is charged from the ground-mounted charging device 8021 via the cable 8022. When charging, the charging method, the standard of the connector, and the like may be appropriately set by a predetermined method. The charging device 8021 may be a charging station provided in a commercial facility or a household power source. For example, the storage battery 802 mounted on the automobile 8100 by the external power supply by the plug-in technology.
4 can be charged. Charging can be performed by converting AC power into DC power via a conversion device such as an ACDC converter.

Further, although not shown, it is also possible to mount a power receiving device on the vehicle and supply electric power from a ground power transmission device in a non-contact manner to charge the vehicle. In the case of this non-contact power supply system, by incorporating a power transmission device on the road or the outer wall, it is possible to charge the battery not only while the vehicle is stopped but also while the vehicle is running. Further, the non-contact power feeding method may be used to transmit and receive electric power between vehicles. Further, a solar cell may be provided on the exterior portion of the vehicle to charge the storage battery when the vehicle is stopped or running. An electromagnetic induction method or a magnetic field resonance method can be used for such non-contact power supply.

According to one aspect of the present invention, the cycle characteristics of the storage battery can be improved and the reliability can be improved. 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 will contribute to the weight reduction of the vehicle, and thus the cruising range can be improved. Further, 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 a commercial power source at the peak of power demand.

This embodiment can be implemented in combination with other embodiments as appropriate.

(Embodiment 3)
A battery control unit (Battery Management Unit: BMU) that can be used in combination with the storage battery described in the first and second embodiments as a battery cell.
), 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 of a storage battery having battery cells connected in series will be described in particular.

When charging and discharging are repeated for a plurality of battery cells connected in series, the capacity (output voltage) differs depending on the variation in the characteristics between the battery cells. In a battery cell connected in series, the total discharge capacity depends on the battery cell having a small capacity. If the capacity varies, the capacity at the time of discharging becomes small. Further, if charging is performed based on a battery cell having a small capacity, there is a possibility that the charging will be insufficient. Further, if charging is performed with reference to a battery cell having a large capacity, there is a risk of overcharging.

Therefore, the battery control unit of the storage battery having the battery cells connected in series has a function of aligning the capacity variation between the battery cells, which causes insufficient charging and overcharging. There are a resistance method, a capacitor method, an inductor method, etc. as a circuit configuration for aligning the capacity variation between battery cells, but here, an example is a circuit configuration in which a transistor having a small off-current can be used to align the capacitance variation. It will be explained as.

As the transistor having a small off-current, a transistor (OS transistor) having an oxide semiconductor in the channel forming region is preferable. By using an OS transistor having a small off-current in the circuit configuration of the battery control unit of the storage battery, it is possible to reduce the amount of charge leaked from the battery and suppress the decrease in capacity with the passage of time.

The oxide semiconductor used for the channel formation region is In—M—Zn oxide (M is Ga, Sn,
Y, Zr, La, Ce, or Nd) is used. In the target used for forming an oxide semiconductor film, the atomic number ratio of the metal element is In: M: Zn = x ₁ : y ₁ : z ₁ .
_, 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 1
It is preferably / 3 or more and 6 or less, and more preferably 1 or more and 6 or less. By setting z ₁ / y ₁ to 1 or more and 6 or less, a CAAC-OS film can be easily formed as an oxide semiconductor film.

Here, the CAAC-OS film will be described.

The CAAC-OS film is one of the oxide semiconductor films having a plurality of c-axis oriented crystal portions.

Transmission Electron Microscope (TEM: Transmission Electron Microscope)
A composite analysis image of the bright-field image and diffraction pattern of the CAAC-OS film (scope).
Also called a high-resolution TEM image. ) Can be observed to confirm multiple crystal parts.
On the other hand, even with a high-resolution TEM image, it is not possible to confirm a clear boundary between crystal portions, that is, a crystal grain boundary (also referred to as grain boundary). Therefore, it can be said that the CAAC-OS film is unlikely to cause a decrease in electron mobility due to grain boundaries.

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 the metal atoms are arranged in layers in the crystal part. Each layer of metal atom
The shape reflects the unevenness of the surface (also referred to as the formed surface) or the upper surface of the CAAC-OS film, and is arranged in parallel with the formed surface or the upper surface of the CAAC-OS film.

On the other hand, when a high-resolution TEM image of the plane of the CAAC-OS film is observed from a direction substantially perpendicular to the sample surface, it can be confirmed that the metal atoms are arranged in a triangular or hexagonal shape in the crystal portion. However, there is no regularity in the arrangement of metal atoms between different crystal parts.

When the structure of the CAAC-OS film is analyzed using an X-ray diffraction (XRD: X-Ray Diffraction) device, for example, in the analysis of the CAAC-OS film having InGaZnO ₄ crystals by the out-of-plane method, A peak may appear near the diffraction angle (2θ) of 31 °. Since this peak is attributed to the (009) plane of the crystal of InGaZnO ₄ , the crystal of the CAAC-OS film has c-axis orientation, and the c-axis is oriented in a direction substantially perpendicular to the surface to be formed or the upper surface. It can be confirmed that it is.

In the analysis of the CAAC-OS film having InGaZnO ₄ crystals by the out-of-plane method, a peak may appear in the vicinity of 2θ at 31 ° as well as in the vicinity of 2θ at 36 °. The peak in which 2θ is in the vicinity of 36 ° indicates that a part of the CAAC-OS film contains crystals having no c-axis orientation. In the CAAC-OS film, it is preferable that 2θ shows a peak near 31 ° and 2θ does not show a peak near 36 °.

The CAAC-OS film is an oxide semiconductor film having a low impurity concentration. Impurities are hydrogen, carbon,
It is an element other than the main component of the oxide semiconductor film such as silicon and transition metal elements. In particular, elements such as silicon, which have a stronger bond with oxygen than the metal elements constituting the oxide semiconductor film, disturb the atomic arrangement of the oxide semiconductor film by depriving the oxide semiconductor film of oxygen and have crystalline properties. It becomes a factor to reduce. In addition, heavy metals such as iron and nickel, argon, carbon dioxide, etc. have a large atomic radius (or molecular radius), so if they are contained inside the oxide semiconductor film, they disturb the atomic arrangement of the oxide semiconductor film and become crystalline. It becomes a factor to reduce. Impurities contained in the oxide semiconductor film may become a carrier trap or a carrier generation source.

The CAAC-OS film is an oxide semiconductor film having a low defect level density. For example, oxygen deficiency in an oxide semiconductor film may become a carrier trap or a carrier generation source by capturing hydrogen.

A low impurity concentration and a low defect level density (less oxygen deficiency) is called high-purity intrinsic or substantially high-purity intrinsic. Oxide semiconductor films having high-purity intrinsics or substantially high-purity intrinsics have few carrier sources, so that the carrier density can be lowered. therefore,
Transistors using the oxide semiconductor film have electrical characteristics with a negative threshold voltage (
Also known as normal on. ) Is rare. Further, the oxide semiconductor film having high purity intrinsicity or substantially high purity intrinsicity has few carrier traps. Therefore, the transistor using the oxide semiconductor film has a small fluctuation in electrical characteristics and is a highly reliable transistor. The charge captured by the carrier trap of the oxide semiconductor film takes a long time to be released, and may behave as if it were a fixed charge. Therefore, a transistor using an oxide semiconductor film having a high impurity concentration and a high defect level density may have unstable electrical characteristics.

Further, the transistor using the CAAC-OS film has a small fluctuation in electrical characteristics due to irradiation with visible light or ultraviolet light.

Since the OS transistor has a larger bandgap than a transistor (Si transistor) having silicon in the channel forming region, dielectric 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 for the circuit configuration of the battery control unit of the storage battery applied to such battery cells, it is suitable to configure the OS transistor as described above. ing.

FIG. 22 shows an example of a block diagram of the storage battery. The storage battery BT00 shown in FIG. 22 is connected in series with a terminal pair BT01, a terminal pair BT02, a switching control circuit BT03, a switching circuit BT04, a switching circuit BT05, a transformer control circuit BT06, and a transformer circuit BT07. It has a battery unit BT08 including a plurality of battery cells BT09.

Further, in the storage battery BT00 of FIG. 22, a portion composed of a terminal pair BT01, a terminal pair BT02, a switching control circuit BT03, a switching circuit BT04, a switching circuit BT05, a transformer control circuit BT06, and a transformer circuit BT07. Can be called a battery control unit.

The switching control circuit BT03 controls the operation of the switching circuit BT04 and the switching circuit BT05. Specifically, the switching control circuit BT03 determines a battery cell to be discharged (discharged battery cell group) and a battery cell to be charged (charged battery cell group) based on the voltage measured for each battery cell BT09.

Further, the switching control circuit BT03 outputs the control signal S1 and the 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 that controls the switching circuit BT04 so as to connect the terminal pair BT01 and the discharge battery cell group. Further, the control signal S2 is output to the switching circuit BT05. This control signal S2 is a signal that controls the switching circuit BT05 so as to connect the terminal pair BT02 and the rechargeable battery cell group.

Further, in the switching control circuit BT03, based on the configuration of the switching circuit BT04, the switching circuit BT05, and the transformer circuit BT07, the terminals having the same polarity are connected between the terminal pair BT02 and the rechargeable battery cell group. The control signal S1 and the control signal S2 are generated.

The details of the operation of the switching control circuit BT03 will be described.

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

As a method for determining the high voltage cell and the low voltage cell, various methods can be used. For example, the switching control circuit BT03 is based on the voltage of the battery cell BT09 having the highest voltage or the lowest voltage among the plurality of battery cells BT09, and each battery cell BT0.
It may be determined whether 9 is a high voltage cell or a low voltage cell. 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 or not 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.

In the plurality of battery cells BT09, high-voltage cells and low-voltage cells may coexist in various states. For example, the switching control circuit BT03 has a mixture of high-voltage cells and low-voltage cells.
The portion in which the largest number of high-voltage cells are continuously connected in series is referred to as a discharge battery cell group. Further, in the switching control circuit BT03, a portion in which a large number of low-voltage cells are continuously connected in series is used as a rechargeable battery cell group. Further, the switching control circuit BT03 may preferentially select the battery cell BT09, which is close to overcharge or overdischarge, as the discharge battery cell group or the rechargeable battery cell group.

Here, an operation example of the switching control circuit BT03 in the present 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. note that,
For convenience of explanation, FIG. 23 describes a case where four battery cells BT09 are connected in series as an example.

First, in the example of FIG. 23A, assuming that the voltage of the battery cells a to d is the voltage Va to the voltage Vd, the case where the relationship is 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 three consecutive high-voltage cells a to c as the discharge battery cell group. Further, the switching control circuit BT03 determines the low voltage cell D as the rechargeable battery cell group.

Next, in the example of FIG. 23B, the case where the relationship is Vc> Vb = Vc >> Vd is shown. That is, two consecutive low-voltage cells a and b, one high-voltage cell c, and one low-voltage cell d that is about to be over-discharged are connected in series. In this case, the switching control circuit BT03 is
The high voltage cell c is determined as the discharge battery cell group. Further, in the switching control circuit BT03, since the low-voltage cell d is close to over-discharging, the low-voltage cell d is preferentially determined as the rechargeable battery cell group instead of the two consecutive low-voltage cells a and b.

Finally, the example of FIG. 23C shows the case where the relationship is Va> Vb = Vc = Vd. 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. Further, the switching control circuit BT03 determines three consecutive low-voltage cells b to d as a group of rechargeable battery cells.

The switching control circuit BT03 is a control signal in which information indicating a discharge battery cell group to which the switching circuit BT04 is connected is set based on the results determined as in the example of FIGS. 23 (A) to 23 (C) above. S1 and a control signal S2 in which information indicating a rechargeable battery cell group to which the switching circuit BT05 is connected are set are output to the switching circuit BT04 and the switching circuit BT05, respectively.

The above is a description of the details of the operation of the switching control circuit BT03.

The switching circuit BT04 sets the connection destination of the terminal to the 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 a pair of terminals A1 and A2. Switching circuit BT04
Connects one of the terminals A1 and A2 to the positive electrode terminal of the battery cell BT09 located at the most upstream (high potential side) in the discharge battery cell group, and connects the other to the positive electrode terminal in the discharge battery cell group. By connecting to the negative electrode terminal of the battery cell BT09 located at the most downstream (low potential side), the connection destination of the terminal to BT01 is set. The switching circuit BT04 can recognize the position of the discharge battery cell group by using the information set in the control signal S1.

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

The terminal pair BT02 is composed of a pair of terminals B1 and B2. Switching circuit BT05
Connects one of the terminals B1 and B2 to the positive electrode terminal of the battery cell BT09 located at the most upstream (high potential side) of the rechargeable battery cell group, and connects the other to the positive electrode terminal of the rechargeable battery cell group. By connecting to the negative electrode terminal of the battery cell BT09 located at the most downstream (low potential side), the connection destination of the terminal to BT02 is set. The switching circuit BT05 can recognize the position of the rechargeable battery cell group by using the information set in the control signal S2.

24 and 2 are circuit diagrams showing configuration examples of the switching circuit BT04 and the switching circuit BT05.
Shown in 5.

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, bus BT1
2 is connected to the terminal A2. One of the source or drain of the plurality of transistors BT10 is connected to the buses BT11 and BT12 alternately every other one. Further, the other of the source or drain of the plurality of transistors BT10 is connected between two adjacent battery cells BT09.

Of the plurality of transistors BT10, the other of the source or drain of the transistor BT10 located at the uppermost stream is connected to the positive electrode terminal of the battery cell BT09 located at the uppermost stream of the battery unit BT08. Further, of 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 electrode terminal of the battery cell BT09 located at the most downstream of the battery unit BT08.

The switching circuit BT04 includes one of the plurality of transistors BT10 connected to the bus BT11 and the bus B according to the control signal S1 given to the gates of the plurality of transistors BT10.
The discharge battery cell group and the terminal pair BT01 are connected by making one of the plurality of transistors BT10 connected to the T12 conductive. As a result, the positive electrode terminal of the battery cell BT09 located at the most upstream in the discharge battery cell group is the terminal A1 or A of the terminal pair.
It is connected to either one of 2. Further, the negative electrode terminal of the battery cell BT09 located at the most downstream side in the discharge battery cell group is connected to either one of the terminals A1 or A2 of the terminal pair, that is, the terminal not connected to the positive electrode terminal.

It is preferable to use an OS transistor for the transistor BT10. Since the OS transistor has a small off current, the amount of charge leaked from the battery cells that do not belong to the discharge battery cell group can be reduced, and the decrease in capacity with the passage of time can be suppressed. In addition, the OS transistor is less likely to undergo dielectric breakdown when a high voltage is applied. Therefore, even if the output voltage of the discharge battery cell group is large, the battery cell BT09 to which the transistor BT10 to be in a non-conducting state is connected and the terminal pair BT01 can be in an insulated state.

Further, 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. Bus BT15 and BT
16 is arranged between the plurality of transistors BT13 and the current control switch BT14. One of the source or drain of the plurality of transistors BT13 is connected to the buses BT15 and BT16 alternately every other one. Further, the other of the source or drain of the plurality of transistors BT13 is connected between two adjacent battery cells BT09.

Of the plurality of transistors BT13, the other of the source or drain of the transistor BT13 located at the uppermost stream is connected to the positive electrode terminal of the battery cell BT09 located at the uppermost stream of the battery unit BT08. Further, of 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 electrode terminal of the battery cell BT09 located at the most downstream of the battery unit BT08.

As with the transistor BT10, it is preferable to use an OS transistor for the transistor BT13. Since the OS transistor has a small off current, the amount of charge leaked from the battery cells that do not belong to the rechargeable battery cell group can be reduced, and the decrease in capacity with the passage of time can be suppressed. In addition, the OS transistor is less likely to undergo dielectric breakdown when a high voltage is applied. for that reason,
Even if the voltage for charging the rechargeable battery cells is large, the transistor BT is in a non-conducting state.
The battery cell BT09 to which the 13 is connected and the terminal pair BT02 can be in an insulated state.

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

The switch included in the switch vs. BT17 and the switch vs. BT18 is the transistor BT10.
And like the transistor BT13, it is preferable to use an OS transistor.

The switching circuit BT05 connects the rechargeable battery cell group and the terminal pair BT02 by controlling the combination of the on / off state of the transistor BT13 and the current control switch BT14 according to the control signal S2.

As an example, the switching circuit BT05 includes a rechargeable battery cell group and a terminal pair BT0 as follows.
Connect with 2.

The switching circuit BT05 makes the transistor BT13 connected to the positive electrode terminal of the battery cell BT09 located upstream in the rechargeable battery cell group conductive in response to the control signal S2 given to the gates of the plurality of transistors BT10. .. Further, the switching circuit BT05 is a transistor BT13 connected to the negative electrode terminal of the battery cell BT09 located at the most downstream side in the rechargeable battery cell group in response to the control signal S2 given to the gates of the plurality of transistors BT10.
To be in a conductive state.

The polarity of the voltage applied to the terminal pair BT02 may change depending on the configuration of the discharge battery cell group connected to the terminal pair BT01 and the transformer circuit BT07. Further, in order to pass a current in the direction of charging the rechargeable battery cell group, it is necessary to connect terminals having the same polarity between the terminal pair BT02 and the rechargeable battery cell group. Therefore, the current control switch BT14 receives the control signal S2.
Switch vs. BT17 and switch vs. BT depending on the polarity of the voltage applied to the terminal vs. BT02.
It is controlled to switch each of the 18 connection destinations.

As an example, a state in which a voltage such that the terminal B1 is the positive electrode and the terminal B2 is the negative electrode is applied to the terminal pair BT02 will be described. At this time, the most downstream battery cell BT09 of the battery unit BT08
When is a group of rechargeable battery cells, the switch pair BT17 is controlled by the control signal S2 so as to be connected to the positive electrode terminal of the battery cell BT09. That is, the switch connected to the bus BT16 of the switch vs. BT17 is turned on, and the bus BT1 of the switch vs. BT17 is turned on.
The switch connected to 5 is turned off. On the other hand, the switch vs. BT18 is the control signal S2.
Is controlled so as to be connected to the negative electrode terminal of the battery cell BT09. That is, the switch connected to the bus BT15 of the switch vs. BT18 is turned on, and the switch vs. B
The switch connected to the bus BT16 of T18 is turned off. In this way, terminals having the same polarity are connected between the terminal pair BT02 and the rechargeable battery cell group. Then, the direction of the current flowing from the terminal pair BT02 is controlled so as to be the direction of charging the rechargeable battery cell group.

Further, the current control switch BT14 is not the changeover circuit BT05 but the changeover circuit BT.
It may be included in 04. In this case, the polarity of the voltage applied to the terminal pair BT02 is controlled by controlling the polarity of the voltage applied to the terminal pair BT01 according to the current control switch BT14 and the control signal S1. The current control switch BT14 has a terminal pair BT02.
Controls the direction of the current flowing through the rechargeable battery cells.

FIG. 25 is a circuit diagram showing a configuration example of the switching circuit BT04 and the switching circuit BT05, which are different from those in FIG. 24.

In FIG. 25, the switching circuit BT04 has a plurality of transistor pairs BT21 and a bus BT24.
And a bus BT25. The bus BT24 is connected to the terminal A1. Further, the bus BT25 is connected to the terminal A2. One end of the plurality of transistor pairs BT21 is branched by the transistor BT22 and the transistor BT23, respectively. One of the source or drain of the transistor BT22 is connected to the bus BT24. Further, one of the source and drain of the transistor BT23 is connected to the bus BT25. also,
The other ends of the plurality of transistor pairs are connected between two adjacent battery cells BT09. Of the plurality of transistor pairs BT21, the other end of the transistor pair BT21 located at the most upstream is connected to the positive electrode terminal of the battery cell BT09 located at the most upstream of the battery unit BT08. Further, among the plurality of transistor pairs BT21, the other end of the transistor pair BT21 located at the most downstream is connected to the negative electrode terminal of the battery cell BT09 located at the most downstream of the battery unit BT08.

The switching circuit BT04 switches the connection destination of the transistor to BT21 to either terminal A1 or terminal A2 by switching the conduction / non-conduction state of the transistor BT22 and the transistor BT23 according to the control signal S1. Specifically, transistor B
If T22 is in a conductive state, the transistor BT23 is in a non-conducting state, and the connection destination is the terminal A1. On the other hand, if the transistor BT23 is in a conductive state, the transistor BT22
Is in a non-conducting state, and its connection destination is terminal A2. Which of the transistor BT22 and the transistor BT23 is in the conductive state is determined by the control signal S1.

Two transistor pairs BT21 are used to connect the terminal pair BT01 and the discharge battery cell group. Specifically, the discharge battery cell group and the terminal pair BT01 are connected by determining the connection destinations of the two transistor pairs BT21 based on the control signal S1. 2
Each connection destination of the two transistor pairs BT21 is controlled by the control signal S1 so that one becomes the terminal A1 and the other becomes the terminal A2.

The switching circuit BT05 includes a plurality of transistor pairs BT31, and a bus BT34 and a bus BT.
It has 35 and. The bus BT34 is connected to the terminal B1. In addition, the bus BT35
It is connected to terminal B2. One end of the plurality of transistor pairs BT31 is branched by the transistor BT32 and the transistor BT33, respectively. One end branched by the transistor BT32 is connected to the bus BT34. Further, one end branched by the transistor BT33 is connected to the bus BT35. Also, multiple transistor pairs BT31
The other end of is connected between two adjacent battery cells BT09. Of the plurality of transistor pairs BT31, the other end of the transistor pair BT31 located at the uppermost stream is
It is connected to the positive electrode terminal of the battery cell BT09 located at the uppermost stream of the battery unit BT08. Further, among the plurality of transistor pairs BT31, the other end of the transistor pair BT31 located at the most downstream is connected to the negative electrode terminal of the battery cell BT09 located at the most downstream of the battery unit BT08.

The switching circuit BT05 switches the connection destination of the transistor to BT31 to either terminal B1 or terminal B2 by switching the conduction / non-conduction state of the transistor BT32 and the transistor BT33 according to the control signal S2. Specifically, transistor B
If T32 is in a conductive state, the transistor BT33 is in a non-conducting state, and the connection destination is the terminal B1. Conversely, if the transistor BT33 is in a conductive state, the transistor BT32
Is in a non-conducting state, and its connection destination is terminal B2. Which of the transistor BT32 and the transistor BT33 is in the conductive state is determined by the control signal S2.

Two transistor pairs BT31 are used to connect the terminal pair BT02 and the rechargeable battery cell group. Specifically, the rechargeable battery cell group and the terminal pair BT02 are connected by determining the connection destinations of the two transistor pairs BT31 based on the control signal S2. 2
Each connection destination of the two transistor pairs BT31 is controlled by the control signal S2 so that one becomes the terminal B1 and the other becomes the terminal B2.

Further, 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 is applied to the terminal pair BT02 such that the terminal B1 is the positive electrode and the terminal B2 is the negative electrode, the transistor BT32 is in a conductive state and the transistor BT33 is non-conducting in the transistor pair BT31 on the upstream side. It is controlled by the control signal S2 so as to be in a state. On the other hand, the transistor pair BT31 on the downstream side is controlled by the control signal S2 so that the transistor BT33 is in a conductive state and the transistor BT32 is in a non-conducting state. When a voltage is applied to the terminal pair BT02 such that the terminal B1 is the negative electrode and the terminal B2 is the positive electrode, the transistor BT33 is in a conductive state and the transistor BT32 is in a non-conducting state in the transistor pair BT31 on the upstream side. As such, it is controlled by the control signal S2. On the other hand, the transistor pair BT31 on the downstream side has a control signal S2 so that the transistor BT32 is in a conductive state and the transistor BT33 is in a non-conducting state.
Is controlled by. In this way, terminals having the same polarity are connected between the terminal pair BT02 and the rechargeable battery cell group. Then, the direction of the current flowing from the terminal pair BT02 is controlled so as to be the direction of charging the rechargeable battery cell group.

The transformer control circuit BT06 controls the operation of the transformer circuit BT07. The transformer control circuit BT06 generates a transformer signal S3 that controls the operation of the transformer 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 rechargeable battery cell group. Then, it is output to the transformer circuit BT07.

If 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, an excessively large charging voltage is applied to the rechargeable battery cell group. Need to be prevented. Therefore, the transformer control circuit BT06 outputs a transformer signal S3 that controls the transformer circuit BT07 so as to lower the discharge voltage (Vdis) within a range in which the rechargeable battery cell group can be charged.

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 rechargeable battery cell group, the charging voltage required for charging the rechargeable battery cell group is secured. There is a need. Therefore, the transformer circuit BT06 is a transformer circuit BT so as to boost the discharge voltage (Vdis) within a range in which an excessive charge voltage is not applied to the rechargeable battery cell group.
The transformer signal S3 that controls 07 is output.

The voltage value to be an excessive charging voltage can be determined in consideration of the product specifications of the battery cell BT09 used in the battery unit BT08 and the like. Further, the voltage boosted and stepped down by the transformer circuit BT07 is applied to the terminal pair BT02 as a charging voltage (Vcha).

Here, an operation example of the transformer control circuit BT06 in the present embodiment is shown in FIGS. 26 (A) to 26 (C).
Will be described using. 26 (A) to 26 (C) are concepts for explaining an operation example of the transformer control circuit BT06 corresponding to the discharge battery cell group and the rechargeable battery cell group described in FIGS. 23 (A) to 23 (C). It is a figure. 26 (A) to 26 (C) show the battery control unit BT41. As described above, the battery control unit BT41 has a terminal pair BT01 and a terminal pair B.
T02, switching control circuit BT03, switching circuit BT04, and switching circuit BT0
It is composed of 5, a transformer control circuit BT06, and a transformer circuit BT07.

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, 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 transformation control circuit BT06 is a discharge voltage (Vdi) based on the ratio of the number of battery cells BT09 included in the charging electric ground cell group when the number of battery cells BT09 included in the discharge battery cell group is used as a reference.
The buck-boost ratio N of s is calculated.

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 applied as it is to the terminal to BT02 without transforming, the rechargeable battery Excessive voltage may be applied to the battery cell BT09 included in the cell group via the terminal pair BT02. Therefore, in the case shown in FIG. 26 (A), it is necessary to lower the charging voltage (Vcha) applied to the terminal pair BT02 to be lower than the discharge voltage. Further, in order to charge the rechargeable battery cell group, the charging voltage needs to be larger than the total voltage of the battery cells BT09 included in the rechargeable battery cell group. Therefore, the transformer control circuit B
T06 sets the buck-boost ratio N larger than the ratio of the number of battery cells BT09 included in the charging electric ground cell group when the number of battery cells BT09 included in the discharge battery cell group is used as a reference.

The transformation control circuit BT06 has a buck-boost ratio N of 1 to 2 with respect to the ratio of the number of battery cells BT09 included in the charging electric ground cell group based on the number of battery cells BT09 included in the discharge battery cell group. It is preferable to increase it by about 10%. At this time, the charging voltage becomes larger than the voltage of the rechargeable battery cell group, but the charging voltage is actually equal to the voltage of the rechargeable battery cell group. However, in order to make the voltage of the rechargeable battery cell group equal to the charging voltage according to the buck-boost ratio N, the transformation control circuit BT06 passes a current for charging the rechargeable battery cell group. This current is the transformer control circuit BT0
It becomes the value set to 6.

In the example shown in FIG. 26 (A), the number of battery cells BT09 included in the discharge battery cell group is 3.
Since the number of battery cells BT09 included in the rechargeable battery cell group is one, the transformer control circuit BT06 calculates a value slightly larger than 1/3 as the buck-boost ratio N. Then, the transformer control circuit BT06 steps down the discharge voltage according to the step-up / down ratio N, and outputs a transformer signal S3 converted into a charge voltage to the transformer circuit BT07. Then, the transformer circuit BT07 applies the charging voltage transformed according to the transformer signal S3 to the terminal pair BT02. Then, the battery cell BT09 included in the rechargeable battery cell group is charged by the charging voltage applied to the terminal pair BT02.

Further, in the examples shown in FIGS. 26 (B) and 26 (B), the buck-boost ratio N is calculated in the same manner as in FIG. 26 (A). In the example shown in FIGS. 26 (B) and 26 (C), since the number of battery cells BT09 included in the discharge battery cell group is equal to or less than the number of battery cells BT09 included in the rechargeable battery cell group, the buck-boost ratio N is 1 or more. Therefore, in this case, the transformer control circuit BT06 outputs a transformer signal S3 that boosts the discharge voltage and converts it into a received voltage.

The transformer circuit BT07 converts the discharge voltage applied to the terminal pair BT01 into a charge voltage based on the transformer signal S3. Then, the transformer circuit BT07 applies the converted charging voltage to the terminal to BT0.
Apply to 2. Here, the transformer circuit BT07 electrically insulates between the terminal pair BT01 and the terminal pair BT02. As a result, the transformer circuit BT07 has the absolute voltage of the negative electrode terminal of the battery cell BT09 located most downstream in the discharge battery cell group and the negative electrode terminal of the battery cell BT09 located most downstream in the rechargeable battery cell group. Prevents short circuit due to difference from absolute voltage. Further, as described above, the transformer circuit BT07 converts the discharge voltage, which is the total voltage of the discharge battery cells, into the charge voltage based on the transformer signal S3.

Further, the transformer circuit BT07 is, for example, an isolated DC (Direct Current) -DC.
A converter or the like can be used. In this case, the transformer control circuit BT06 is an isolated DC-
By outputting the signal for controlling the on / off ratio (duty ratio) of the DC converter as the transformer signal S3, the charging voltage converted by the transformer circuit BT07 is controlled.

The isolated DC-DC converter includes flyback method, forward method, and RCC (
There are a Ringing Choose Converter) method, a push-pull method, a half-bridge method, a full-bridge method, and the like, and an appropriate method is selected according to the magnitude of the target output voltage.

FIG. 27 shows the configuration of the transformer circuit BT07 using the isolated DC-DC converter. Insulated type D
The C-DC converter BT51 has a switch unit BT52 and a transformer unit BT53.
The switch unit BT52 is a switch for switching on / off the operation of the isolated DC-DC converter, and is, for example, a MOSFET (Metal-Oxide-Semiconduc).
It is realized by using a tor Field-Effective Transistor), a bipolar transistor, or the like. Further, the switch unit BT52 periodically switches between the on state and the off state of the isolated DC-DC converter BT51 based on the transformer signal S3 that controls the on / off ratio, which is output from the transformer control circuit BT06. The switch unit BT52 may have various configurations depending on the method of the isolated DC-DC converter used. The transformer unit BT53 converts the discharge voltage applied from the terminal pair BT01 into a charge voltage. In detail,
The transformer unit BT53 operates in conjunction with the on / off state of the switch unit BT52, and converts the discharge voltage into a charging voltage according to the on / off ratio thereof. This charging voltage is the switch unit BT5.
In the switching cycle of 2, the longer the time of being in the ON state, the larger the value. On the other hand, the charging voltage becomes smaller as the on-state time becomes shorter in the switching cycle of the switch unit BT52. When an isolated DC-DC converter is used, the terminal pair BT01 and the terminal pair BT02 can be insulated from each other inside the transformer unit BT53.

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

First, the storage battery BT00 acquires the voltage measured for each of the plurality of battery cells BT09 (step S001). Then, the storage battery BT00 determines whether or not the condition for starting the operation of aligning 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 voltage measured for each of the plurality of battery cells BT09 is equal to or greater than a predetermined threshold value. If this start condition is not satisfied (step S002)
: NO), Since the voltage of each battery cell BT09 is 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 a process of aligning the voltages of the battery cells BT09. In this process, the storage battery BT00 is a battery cell B based on the measured voltage of each cell.
It is determined whether T09 is a high voltage cell or a low voltage cell (step S003). And the storage battery B
T00 determines the discharge battery cell group and the rechargeable battery cell group based on the determination result (step S004). Further, in the storage battery BT00, the determined discharge battery cell group is connected to the terminal to BT01.
A control signal S1 to be set to the connection destination of the above and a control signal S2 to set the determined rechargeable battery cell group to the connection destination of the terminal to BT02 are generated (step S005). The storage battery BT00 uses the generated control signal S1 and control signal S2 as a switching circuit BT04 and a switching circuit BT0.
Output to 5 respectively. Then, the terminal pair BT01 and the discharge battery cell group are connected by the switching circuit BT04, and the terminal pair BT02 and the discharge battery cell group are connected by the switching circuit BT05 (step S006). Further, the storage battery BT00 generates a transformation 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). And the storage battery BT00
Based on the transformer signal S3, the discharge voltage applied to the terminal pair BT01 is converted into a charge voltage and applied to the terminal pair BT02 (step S008). As a result, the electric charge of the discharge battery cell group is transferred to the rechargeable battery cell group.

Further, in the flowchart of FIG. 28, a plurality of steps are described in order, but the execution order of each step is not limited to the order of description.

As described above, according to the present embodiment, when the electric charge is transferred from the discharge battery cell group to the rechargeable battery cell group,
Unlike the capacitor method, it does not require a configuration in which the electric charge from the discharge battery cell group is temporarily stored and then discharged to the rechargeable battery cell group. This makes it possible to improve the charge transfer efficiency per unit time. Further, the discharge battery cell group and the rechargeable battery cell group are individually switched by the switching circuit BT04 and the switching circuit BT05.

Further, the discharge voltage applied to the terminal pair BT01 by the transformer circuit BT07 is the charge voltage based on the number of battery cells BT09 included in the discharge battery cell group and the number of battery cells BT09 group included in the charge battery cell group. Is converted to and applied to the terminal pair BT02. Thereby, no matter how the battery cell BT09 on the discharging side and the charging side is selected, the charge transfer can be realized without any problem.

Further, by using the OS transistor for the transistor BT10 and the transistor BT13, the amount of electric charge leaked from the battery cell BT09 which does not belong to the rechargeable battery cell group and the discharge battery cell group can be reduced. As a result, the battery cell BT09 that does not contribute to charging and discharging
It is possible to suppress a decrease in the capacity of. Further, the OS transistor has a smaller fluctuation in characteristics with respect to heat than the Si transistor. As a result, even if the temperature of the battery cell BT09 rises, normal operation such as switching between a conductive state and a non-conducting state according to the control signals S1 and S2 can be performed.

It should be noted that this embodiment can be implemented in combination with other embodiments as appropriate.

(Embodiment 4)
≪Other structural examples of storage batteries≫

FIG. 29 shows a storage battery 2100 according to an aspect of the present invention. The storage battery is 3 of the exterior body 2107.
The sides are sealed. It also has a positive electrode lead 2121 and a negative electrode lead 2125, and a positive electrode 2111, a negative electrode 2115 and a separator 2103. Since the figure is 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 not formed with each other's active materials. It is in contact with.

Here, a part of the manufacturing method of the storage battery 2100 shown in FIG. 29 will be described with reference to FIG.

First, the negative electrode 2115 is placed on the separator 2103 (FIG. 30 (A)). At this time, the negative electrode active material layer of the negative electrode 2115 is arranged so as to overlap with the separator 2103.

Next, the separator 2103 is bent, and the separator 2103 is placed on the negative electrode 2113. Next, the positive electrode 2111 is superposed on the separator 2103 (FIG. 30B). At this time, the positive electrode active material layer 2102 possessed by the positive electrode 2111 is arranged so as to overlap the separator 2103 and the negative electrode active material layer 2106. When an electrode having an active material layer formed on one side of the current collector is used, 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 face each other via the separator 2103. Deploy.

When a material that can be heat-welded such as polypropylene is used for the separator 2103, the electrodes are displaced during the manufacturing process by heat-welding the region where the separators 2103 are overlapped and then stacking the next electrodes. Can be suppressed. Specifically, the negative electrode 2115 or the positive electrode 2111
Area in which the separators 2103 are superimposed on each other, for example, FIG. 30 (B).
It is preferable to heat-weld the region shown by the region 2103a.

By repeating this step, as shown in FIG. 30C, the positive electrode 2111 and the negative electrode 2115 can be stacked with the separator 2103 interposed therebetween.

In addition, a plurality of negative electrodes 2115 and a plurality of positive electrodes 2111 may be arranged so as to be alternately sandwiched between the separator 2103 which has been repeatedly bent in advance.

Next, as shown in FIG. 30C, the separator 2103 covers the plurality of positive electrodes 2111 and the plurality of negative electrodes 2115.

Further, as shown in FIG. 30 (D), a plurality of positive electrodes 2111 and a plurality of negative electrodes 2115 are obtained by heat-welding a region where the separators 2103 are overlapped with each other, for example, a region 2103b shown in FIG. 30 (D). Cover with separator 2103 and bind.

The plurality of positive electrodes 2111, the plurality of negative electrodes 2115, and the separator 2103 may be bound together using a binding material.

In order to stack the positive electrode 2111 and the negative electrode 2115 in such a process, the separator 210
3 has a region sandwiched between a plurality of positive electrodes 2111 and a plurality of negative electrodes 2115, and a region arranged so as to cover the plurality of positive electrodes 2111 and the plurality of negative electrodes 2115 in one separator 2103. ..

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

The adhesive 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, the positive electrode lead 2121 and the negative electrode lead 2.
For configurations other than the position and shape of 125, the description of the first embodiment can be taken into consideration. Further, the method for manufacturing the storage battery 2100d other than the step of stacking the positive electrode 2111 and the negative electrode 2115 is described.
The production method described in the first embodiment can be taken into consideration.

FIG. 31 shows a storage battery 100e different from that of FIG. 29. 31 (A) is a perspective view of the storage battery 2200, and FIG. 31 (B) is a top view of the storage battery 2200. 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. 31 (D) is a cross-sectional view taken along the one-dot broken line H1-H2 of FIG. 31 (B). In addition, in FIG. 31 (D), in order to make the figure clear, the first electrode assembly 2130, the electrode assembly 2131 and the separator 2
103 is excerpted and shown. Further, since the figure is 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 not formed with each other's active materials. It is in contact with.

The storage battery 2200 shown in FIG. 31 differs from the storage battery 2100 in FIG. 29 in the arrangement of the positive electrode 2111 and the negative electrode 2115 and the arrangement of the separator 2103.

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.

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

Further, as shown in FIG. 31 (D), the plurality of first electrode assemblies 2130 and the plurality of second electrode assemblies 2131 are covered with the wound separator 2103.

Here, a part of the method for manufacturing the storage battery 2200 shown in FIG. 31 will be described with reference to FIG. 32.

First, the first electrode assembly 2130 is arranged on the separator 2103 (FIG. 32 (A)).

Next, the separator 2103 is bent and the separator 21 is placed on the first electrode assembly 2130.
Repeat 03. Next, two sets of the second electrode assembly 2131 are superposed on the top and bottom of the first electrode assembly 2130 via the separator 2103 (FIG. 32 (B)).

Next, the separator 2103 is wound so as to cover the two sets of the second electrode assembly 2131. Further, 2 sets are placed above and below the second electrode assembly 2131 via the separator 2103.
The first electrode assembly 2130 of the set is overlapped (FIG. 32 (C)).

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

In order to stack the plurality of first electrode assemblies 2130 and the plurality of electrode assemblies 2131 in such a step, these electrode assemblies are arranged between the spirally wound separators 2103.

It is preferable that the positive electrode 2111a of the electrode assembly 2130 arranged on the outermost side does not have the positive electrode active material layer 2102 on the outer side.

Further, in FIGS. 32 (C1) and 32 (C2), the configuration in which the electrode assembly has three electrodes and two separators is shown, but one aspect of the present invention is not limited to this. 4 or more electrodes, 3 separators
It may be configured to have more than one sheet. By increasing the number of electrodes, the capacity of the storage battery 2200 can be further improved. Further, the configuration may have two electrodes and one separator. When the number of electrodes is small, a storage battery 2200 that is more resistant to bending can be used. Further, in FIG. 32 (D), the storage battery 2200 has three sets of the first electrode assembly 2130 and two sets of the second electrode assembly 2131.
Although the configuration having a set is shown, one aspect of the present invention is not limited to this. It may be configured to have more electrode assemblies. By increasing the number of electrode assemblies, the capacity of the storage battery 2200 can be further improved. Further, it may be configured to have a smaller number of electrode assemblies. If the number of electrode assemblies is small, a storage battery 2200 that is more resistant to bending can be used.

In addition to the arrangement of the positive electrode 2111 and the negative electrode 2115 and the arrangement of the separator 2103 of the storage battery 2200, the description of FIG. 29 can be referred to.

This embodiment can be implemented in combination with other embodiments as appropriate.

100a Laminated body 100b Laminated body 100c Laminated body 100d Laminated body 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 solution 110 Lithium ion storage battery 115 Lead electrode 116 Exterior body 117 Internal structure Object 118 Void 300 Storage 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 collector 309 Negative electrode active material layer 310 Separator 400 Storage battery 402 Positive electrode 404 Negative electrode 500 Storage battery 501 Positive electrode collection Electrode 502 Positive Electrode Layer 503 Positive Electrode 504 Negative Electrode Collector 505 Negative Electrode Active Material Layer 506 Negative Electrode 507 Separator 508 Electrolyte Solution 509 Exterior 510 Positive Electrode Tab Electrode 511 Negative Electrode Tab Electrode 515 Tab Electrode 516 Tab Electrode 600 Storage 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 Insulation Plate 609 Insulation Plate 610 Gasket 611 PTC Element 612 Safety Valve Mechanism 900 Circuit Board 910 Label 911 Terminal 912 Circuit 913 Storage 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 Curvature center 1102 Edge near the center of curvature of the internal structure 1103 From the center of curvature of the internal structure Far-side end 1104 Closer to the center of curvature of the internal structure 1105 End of the internal structure far from the center of curvature 1106 Point near the center of curvature of the internal structure 1700 Curved 1701 Flat 1702 Curve 1703 Radius of curvature 1704 Center of curvature 1800 Center of curvature 1801 Film 1802 Radius of curvature 1803 Film 1804 Radiation of curvature 1805 Electrodes, electrolytes, etc. 2100 Storage battery 2101 Positive electrode current collector 2102 Positive electrode active material layer 2103 Separator 2103a Region 2103b Region 2105 Negative electrode current collector 2106 Material layer 2107 Exterior 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 Installation 7101 Housing 7102 Display 7103 Operation button 7104 Storage battery 7400 Mobile phone 7401 Housing 7402 Display 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 Transformation signal BT00 Storage battery BT01 Terminal vs. BT02 Terminal vs. BT03 Switching control circuit BT04 Switching circuit BT05 Switching circuit BT06 Transformation control circuit BT07 Transformation circuit BT08 Battery section BT09 Battery cell BT10 Transistor BT11 Bus BT12 Bus BT13 Transistor BT BT16 Bus BT17 Switch vs BT18 Switch vs BT21 Transistor vs BT22 Transistor BT23 Transistor BT24 Bus BT25 Bus BT31 Transistor vs BT32 Transistor BT33 Transistor BT34 Bus BT35 Bus BT41 Battery control unit BT51 Insulated DC-DC converter BT52 Switch section BT53 Step S003 Step S004 Step S005 Step S006 Step S007 Step S008 Step

Claims (1)

It has an internal structure and an exterior body,
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 first laminated body has a first current collector.
The second laminated body has a second current collector and has a second current collector.
The surface of the first current collector has a first region in which the electrode active material is not formed.
The surface of the second current collector has a second region in which the electrode active material is not formed.
The exterior body encloses the internal structure and
A flexible lithium-ion storage battery in which at least a part of the first region is in contact with at least a part of the second region.

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