Power storage device

Abstract

To provide a power storage device which has flexibility, in which a capacitance is unlikely to deteriorate even if it is curved, has a high capacity, and has a small size.SOLUTION: A power storage device includes: a first electrode; a second electrode; and an electrolyte. The first electrode functions as any one of a positive electrode and a negative electrode. The second electrode functions as the other one of the positive electrode and the negative electrode. Both of the first electrode and the second electrode includes a region to be overlapped each other. The first electrode includes a first collector and a first active material layer. The first collector includes a first surface and a second surface. The first active material layer is provided to the first surface, and the first collector includes a first folding part having the second surface as an internal side. The second surface includes the first region and the second region. The first region includes a region to be overlapped with the second region. The first region includes a region which is connected to the second region at a place that is different from the first folding part.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] One aspect of the present invention relates to a power storage device and an electronic device.

[0002] Note that one aspect of the present invention is not limited to the above technical field. One aspect of the invention disclosed in this specification and the like relates to an article, a method, or a manufacturing method. One aspect of the present invention relates to a process, a machine, a manufacture, or a composition of matter. Therefore, as a more specific technical field of one aspect of the present invention disclosed in this specification, semiconductor devices, display devices, light-emitting devices, power storage devices, storage devices, their driving methods, or their manufacturing methods can be cited as an example.

[0003] Note that in this specification, the electronic device refers to all devices driven by electricity, and electro-optical devices and information terminal devices are all electronic devices. Some electronic devices have a built-in power storage device. Here, the definition of "built-in" needless to say means built-in so that it cannot be removed and replaced, and those that can be freely removed such as a battery pack are also called built-in.

Background Art

[0004] In recent years, various power storage devices such as lithium ion secondary batteries, lithium ion capacitors, and air batteries have been actively developed. In particular, lithium ion secondary batteries with high output and high energy density are used in portable information terminals such as mobile phones, smartphones, and notebook computers, electronic devices such as portable music players and digital cameras, or medical devices, hybrid vehicles (HEV), electric vehicles (EV), fuel cell vehicles, or plug-in hybrid vehicles (PHEV). ​Along with the development of the semiconductor industry, the demand for next-generation clean energy vehicles such as has rapidly expanded and become indispensable in modern information-based societies as a source of rechargeable energy.

[0005] On the other hand, the development of wearable devices that users wear on their bodies is being actively carried out. To enable users to use them more comfortably, many wearable devices have a curved shape or are flexible. In addition, in order to be mounted on such wearable devices, the development of a power storage device that is curved or has flexibility is underway.

[0006] For example, Patent Document 1 discloses a sheet-like power storage device that can be curved in at least one axial direction and an electronic device equipped with the power storage device.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] In the development of power storage devices for use in wearable devices and the like, there is a demand for the realization of a power storage device that has a large capacity and flexibility. In addition, there is a demand for the development of a power storage device that is less likely to deteriorate in capacity and cycle characteristics even when bent. There is also a demand for the development of a small and large-capacity power storage device.

[0009] Therefore, an aspect of the present invention aims to provide a flexible power storage device. Also ​​​​, one aspect of the present invention aims to suppress the deterioration of capacitance and cycle characteristics when the power storage device is bent. Another aspect of the present invention aims to provide an electronic device having a power storage device that can be bent. Also, one aspect of the present invention aims to provide a high-capacity power storage device. Another aspect of the present invention aims to increase the capacitance per unit volume or per unit weight of the power storage device. Further, one aspect of the present invention aims to miniaturize the power storage device. Or, one aspect of the present invention aims to provide a novel electrode, a novel secondary battery, a novel power storage device, or a novel electronic device. It should be noted that the description of these problems does not prevent the existence of other problems. It should be noted that one aspect of the present invention does not necessarily need to solve all of these problems. Other problems will become apparent from the description in the specification, drawings, claims, etc., and it is possible to extract other problems from the description in the specification, drawings, claims, etc.

[0010]

Means for Solving the Problems

[0011] Or, one aspect of the present invention aims to provide a novel electrode, a novel secondary battery, a novel power storage device, or a novel electronic device. It should be noted that the description of these problems does not prevent the existence of other problems. It should be noted that one aspect of the present invention does not necessarily need to solve all of these problems. Other problems will become apparent from the description in the specification, drawings, claims, etc., and it is possible to extract other problems from the description in the specification, drawings, claims, etc.

Means for Solving the Problems

[0012] One aspect of the present invention has a first electrode, a second electrode, and an electrolyte. The first electrode functions as either a positive electrode or a negative electrode, and the second electrode functions as the other of the positive electrode and the negative electrode. The first electrode and the second electrode have an overlapping region. The first electrode has a first current collector and a first active material layer. The first current collector has a first surface and a second surface. The first active material layer is provided on the first surface. The first current collector has a first bent portion with the second surface on the inner side. The second surface has a first region and a second region. The first region... ​​​​​​​​​​​ It has a region overlapping with the region of 2, and the first region has a region connecting to the second region at a location different from the first bending portion. The power storage device is such.

[0013] Also, in one aspect of the present invention, in the above configuration, the first current collector has a second bending portion with the first surface on the inside, and the first active material layer is not provided on the second bending portion. The power storage device is such.

[0014] Also, in one aspect of the present invention, in each of the above configurations, the second electrode has a second current collector and a second active material layer. The second current collector has a third bending portion, and the third bending portion is substantially parallel to the first bending portion. The power storage device is such.

[0015] Also, in the power storage device having each of the above configurations, it has an exterior body surrounding the first electrode, the second electrode, and the electrolytic solution. It is more preferable that the exterior body has a film, and it is more preferable that the electrolytic solution is in a gel state. Also, it is more preferable that the first electrode has a friction layer, and the friction layer is provided on the second surface.

[0016] Also, in one aspect of the present invention, it has a first electrode, a second electrode, a first lead, a second lead, and an exterior body. The first electrode functions as either the positive electrode or the negative electrode, the second electrode functions as the other of the positive electrode and the negative electrode, the first lead is electrically connected to the first electrode, the second lead is electrically connected to the second electrode, the exterior body has a first side, a second side, a third side, and a fourth side. The first side is not adjacent to the second side. The exterior body has a bending portion, and the bending portion includes the first side and A power storage device that surrounds a first electrode and a second electrode, and a first lead and a second lead overlap on a first side. It is a power storage device.

[0017] Also, in one aspect of the present invention, in the above configuration, when the length of the first side is W and the length of the third side is L it is a power storage device where L ≥ W.

[0018] Also, in one aspect of the present invention, in each of the above configurations, the first electrode and the second electrode have an overlapping region, the first electrode has a first current collector and a first active material layer, the first current collector has a first surface and a second surface, the first active material layer is provided on the first surface, the first current collector has a first bent portion with the second surface on the inside, the second surface has a first region and a second region, the first region has a region overlapping the second region, and the first region has a region connecting to the second region at a location different from the first bent portion. It is a power storage device.

[0019] Also, in one aspect of the present invention, in the power storage device having the above configuration, the first current collector may have a second bent portion with the first surface on the inside, and the first active material layer may not be provided on the second bent portion.

[0020] Also, in one aspect of the present invention, in the power storage device having each of the above configurations, it is more preferable to have flexibility, and it is more preferable to be curved.

[0021] Also, in one aspect of the present invention, it is an electronic device having the power storage device having each of the above configurations and a flexible housing. Also, in one aspect of the present invention, it is an electronic device having the power storage device having each of the above configurations and a housing having a curved portion.

Advantages of the Invention

[0022] ​​​​​​​​​​ According to one aspect of the present invention, in a current collector having a bent portion, the friction between the contacting surfaces can be reduced. As a result, when the power storage device is bent, the electrodes are likely to deform , so that the stress caused by the difference between the inner diameter and the outer diameter of the bent power storage device can be easily released . Further, damage to the positive electrode or the negative electrode can be prevented. Also, according to one aspect of the present invention , when the power storage device is bent, it is possible to prevent the positive electrode and the negative electrode from being excessively displaced and the battery reaction from being hindered . Therefore, a flexible power storage device can be provided . Also, it is possible to provide a power storage device whose capacity and cycle characteristics are less likely to deteriorate even when bent . Further, an electronic device having a flexible power storage device can be provided.

[0023] Also, according to one aspect of the present invention, a large-capacity power storage device can be provided. Also, according to one aspect of the present invention , the capacity per unit volume or per unit weight of the power storage device can be increased. Also , according to one aspect of the present invention, the power storage device can be miniaturized.

[0024] Also, according to one aspect of the present invention, a small-sized power storage device that can be easily mass-produced and bent can be provided. Therefore, according to one aspect of the present invention, a power storage device that is small and easy to mount on a wearable device or the like having a bent shape can be provided. Even when it is necessary to mass-produce a wearable device or the like having a curved shape, the power storage device can be stably supplied.

[0025] Also, a novel electrode, a novel secondary battery, a novel power storage device, or a novel electronic device can be provided . Note that the description of these effects does not preclude the existence of other effects. Oh, one aspect of the present invention does not necessarily have to have all of these effects. Note that this and other effects will become obvious from the descriptions in the specification, drawings, claims, etc., and it is possible to extract these other effects from the descriptions in the specification, drawings, claims, etc. .

Brief Description of the Drawings

[0026]

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Embodiments for Carrying Out the Invention

[0027] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention Without being limited to the following description, those skilled in the art can easily understand that the form and details can be changed in various ways. Also, the present invention should not be construed as being limited to the description of the embodiments shown below. Also, the present invention should not be construed as being limited to the description of the embodiments shown below. It is not limited to this.

[0028] In this specification and the like, "connection" includes cases where it is connected through "something having some electrical action". Here, "something having some electrical action" is not particularly limited as long as it enables the transmission and reception of electrical signals between the connection targets. Here, "something having some electrical action" is not particularly limited as long as it enables the transmission and reception of electrical signals between the connection targets. It is not particularly limited as long as it enables the transmission and reception of electrical signals between the connection targets.

[0029] Note that the term "film" and the term "layer" can be interchanged with each other depending on the case or the situation. For example, the term "conductive layer" may be changed to the term "conductive film". Or, for example, the term "insulating film" may be changed to the term "insulating layer" in some cases. Note that the term "film" and the term "layer" can be interchanged with each other depending on the case or the situation. For example, the term "conductive layer" may be changed to the term "conductive film". It may be possible to change it to the term "conductive film". Or, for example, the term "insulating film" may be changed to the term "insulating layer" in some cases. It may be possible to change it to the term "insulating layer" in some cases.

[0030] The positions, sizes, ranges, etc. of the respective components shown in the drawings and the like may not represent the actual positions, sizes, ranges, etc. in order to facilitate understanding. Therefore, the disclosed invention is not necessarily limited to the positions, sizes, ranges, etc. disclosed in the drawings and the like. Therefore, the disclosed invention is not necessarily limited to the positions, sizes, ranges, etc. disclosed in the drawings and the like. It is not limited to the positions, sizes, ranges, etc. disclosed in the drawings and the like.

[0031] Note that the ordinal numbers such as "first", "second", "third", etc. in this specification and the like are added to avoid confusion of components, and it is noted that they are not numerically limiting. Note that the ordinal numbers such as "first", "second", "third", etc. in this specification and the like are added to avoid confusion of components, and it is noted that they are not numerically limiting.

[0032] In this specification, "parallel" means a state in which two straight lines are arranged at an angle of -10° or more and 10° or less. Therefore, cases of -5° or more and 5° or less are also included. Also, "substantially flat" In this specification, "parallel" means a state in which two straight lines are arranged at an angle of -10° or more and 10° or less. Therefore, cases of -5° or more and 5° or less are also included. Also, "substantially flat" "Row" refers to a state where two straight lines are arranged at an angle of -30° or more and 30° or less. Also, "Vertical" refers to a state where two straight lines are arranged at an angle of 80° or more and 100° or less. Therefore, the case of 85° or more and 95° or less is also included. Also, "substantially vertical" refers to a state where two straight lines are arranged at an angle of 60° or more and 120° or less.

[0033] (Embodiment 1) In this embodiment, a power storage device according to an aspect of the present invention will be described by taking the secondary battery 100 as an example. Also, in this embodiment, the secondary battery 100 will be described with reference to FIGS. 1 to 23.

[0034] [1. Basic Configuration] A perspective view of the secondary battery 100 is shown in FIG. 1(A). The secondary battery 100 has a flexible exterior body 110, a positive electrode lead 141, a negative electrode lead 145, and a sealing layer 140. Also, the secondary battery 100 can be curved as shown in FIG. 1(B).

[0035] A cross-sectional view of the secondary battery 100 along the X1-X2 line is shown in FIG. 2(A), a cross-sectional view along the X3-X4 line is shown in FIG. 3(A), and a cross-sectional view along the Y1-Y2 line is shown in FIG. 4. Also, a cross-sectional view of the curved secondary battery 100 shown in FIG. 1(B) along the X5-X6 line is shown in FIG. 5.

[0036] The secondary battery 100 has a positive electrode 111, a negative electrode 115, a separator 108, and an electrolytic solution 109 at positions surrounded by the exterior body 110. Also, the positive electrode 111 has a positive electrode current collector 101 and a positive electrode active material layer 102. Also, the negative electrode 115 has a negative electrode current collector 105 and a negative electrode active material layer 106. Also, the positive electrode current collector 101, the negative electrode current collector 105, and the separator 108 are stacked. The positive electrode active material layer 102 and the negative electrode active material layer 10 6 face each other with a separator 108 interposed therebetween.

[0037] In the secondary battery 100, the positive electrode current collector 101 and the negative electrode current collector 105 are folded in a zigzag pattern. By folding the positive electrode 111 and the negative electrode 115, even if the areas of the positive electrode 111 and the negative electrode 115 are large, the areas of the positive electrode 111 and the negative electrode 115 can be folded small. This allows the large-capacity secondary battery 100 to be made smaller.

[0038] In this specification, the term "zigzag fold" refers to a series of mountain folds and valley folds made from a plate-shaped member. Shows a repeat structure.

[0039] In this specification, the bent portion refers to a portion formed by bending a plate-like member. A locally bent portion that is separated by bending a plate-like member, or 1 shows a portion located at the boundary between one flat plate portion and the other flat plate portion.

[0040] In this specification, the term "flat" refers to a state in which a plate-shaped member does not have any bent portions. In the present specification and the like, the flat plate-like portion may be curved.

[0041] Next, the structure of the negative electrode 115 will be described with reference to FIGS. 2(A) to 2(E) and FIG. 3(D). do.

[0042] In the negative electrode 115 of the secondary battery 100 shown in FIG. An enlarged view of 15a is shown in FIG. 2(B), and the state in which portion 115a is curved is shown in FIG. 2(C). In the portion 115a shown in FIG. 2B, an enlarged view of a portion 202 surrounded by a dotted line is shown in FIG. As shown in FIG. 2(B) and FIG. 2(E), the negative electrode current collector 105 is a first It has a first surface 221 and a second surface 222, and has a bent portion 211 with the second surface 222 on the inner side. The negative electrode active material layer 106 is provided on the first surface 221 and not provided on the second surface 222. Also, the second surface 222 is divided into a first region 231 and a second region 232 that face each other with the bent portion 211 as a boundary.

[0043] In FIG. 2(B), although not shown for simplicity, with this configuration, the first region 23 1 and the second region 232 are in contact. Since both the first region 231 and the second region 232 are the surfaces of the metal constituting the negative electrode current collector 105, the frictional force acting on the contact surface between the first region and the second region is small. For example, more specifically, the coefficient of static friction between the first region 231 and the second region 232 is smaller than the coefficient of static friction between the negative electrode active material layer 106 and the separator 108. Therefore, when the first region 231 and the second region 232 shift relative to each other, as shown in FIG. 2(C), the negative electrode current collector 105 can be deformed.

[0044] Also, as shown in FIGS. 2(B) and 2(C), the end of the first region 231 and the end of the second region 232 are connected at a welding portion 201a, which is a location different from the bent portion 211. This can prevent the negative electrode current collector 105, and further the negative electrode 115, from being excessively deformed, the distance between the positive electrode active material layer 102 and the negative electrode active material layer 106 from changing, or the negative electrode 115 and the positive electrode 111 from contacting and causing a short circuit.

[0045] Also, it is preferable that the negative electrode 115 does not have the negative electrode active material layer 106 near the bent portion 211. ​​​​​​​​​​​Yes. By doing this, it is possible to prevent the deformation of the negative electrode current collector 105 near the bent portion 211 from being hindered by the negative electrode active material layer 106. Also, in the manufacturing process of the secondary battery 100, when the negative electrode current collector 105 is bent to form the bent portion 211, it is possible to prevent the negative electrode active material layer 106 from peeling off from the negative electrode current collector 105. With the above configuration, when the secondary battery 100 is bent, the negative electrode 115 can deform following the deformation of the entire secondary battery 100. Therefore, the secondary battery 100 can be made into a flexible secondary battery. Also, with the configuration described above, the first region 231 and the second region 232 can easily shift relative to each other, making it easier for the negative electrode current collector 105 to deform. Thus, it is possible to suppress the occurrence of wrinkles in the negative electrode 115 or the local strong bending of the negative electrode 115. Therefore, in the negative electrode 115, it is possible to prevent damage to the negative electrode active material layer 106 or breakage of the negative electrode current collector 105. Consequently, it is possible to suppress the deterioration of the capacity and cycle characteristics of the secondary battery 100 due to bending. Figure 2(D) shows an enlarged view of the welded portion 201 shown in Figure 2(A). The negative electrode current collector 105 has a bent portion 212 with the first surface 221 on the inside. As shown in Figure 2(D), by not providing the negative electrode active material layer 106 in the bent portion 212 with the first surface 221 on the inside, the vicinity of the bent portion 212 of the negative electrode current collector 105 and the edge 213 of the negative electrode current collector 105 can be overlapped and welded to form the welded portion 201. Also

[0046] When the secondary battery 100 is bent, the negative electrode 115 can deform following the deformation of the entire secondary battery 100. Therefore, the secondary battery 100 can be made into a flexible secondary battery. Also, with the configuration described above, the first region 231 and the second region 232 can easily shift relative to each other, making it easier for the negative electrode current collector 105 to deform. Thus, it is possible to suppress the occurrence of wrinkles in the negative electrode 115 or the local strong bending of the negative electrode 115. Therefore, in the negative electrode 115, it is possible to prevent damage to the negative electrode active material layer 106 or breakage of the negative electrode current collector 105. Consequently, it is possible to suppress the deterioration of the capacity and cycle characteristics of the secondary battery 100 due to bending. Figure 2(D) shows an enlarged view of the welded portion 201 shown in Figure 2(A). The negative electrode current collector 105 has a bent portion 212 with the first surface 221 on the inside. As shown in Figure 2(D), by not providing the negative electrode active material layer 106 in the bent portion 212 with the first surface 221 on the inside, the vicinity of the bent portion 212 of the negative electrode current collector 105 and the edge 213 of the negative electrode current collector 105 can be overlapped and welded to form the welded portion 201. Also With the above configuration, when the secondary battery 100 is bent, the negative electrode 115 can deform following the deformation of the entire secondary battery 100. Therefore, the secondary battery 100 can be made into a flexible secondary battery. Also, with the configuration described above, the first region 231 and the second region 232 can easily shift relative to each other, making it easier for the negative electrode current collector 105 to deform. Thus, it is possible to suppress the occurrence of wrinkles in the negative electrode 115 or the local strong bending of the negative electrode 115. Therefore, in the negative electrode 115, it is possible to prevent damage to the negative electrode active material layer 106 or breakage of the negative electrode current collector 105. Consequently, it is possible to suppress the deterioration of the capacity and cycle characteristics of the secondary battery 100 due to bending. Figure 2(D) shows an enlarged view of the welded portion 201 shown in Figure 2(A). The negative electrode current collector 105 has a bent portion 212 with the first surface 221 on the inside. As shown in Figure 2(D), by not providing the negative electrode active material layer 106 in the bent portion 212 with the first surface 221 on the inside, the vicinity of the bent portion 212 of the negative electrode current collector 105 and the edge 213 of the negative electrode current collector 105 can be overlapped and welded to form the welded portion 201. Also With the above configuration, when the secondary battery 100 is bent, the negative electrode 115 can deform following the deformation of the entire secondary battery 100. Therefore, the secondary battery 100 can be made into a flexible secondary battery. Also, with the configuration described above, the first region 231 and the second region 232 can easily shift relative to each other, making it easier for the negative electrode current collector 105 to deform. Thus, it is possible to suppress the occurrence of wrinkles in the negative electrode 115 or the local strong bending of the negative electrode 115. Therefore, in the negative electrode 115, it is possible to prevent damage to the negative electrode active material layer 106 or breakage of the negative electrode current collector 105. Consequently, it is possible to suppress the deterioration of the capacity and cycle characteristics of the secondary battery 100 due to bending. Figure 2(D) shows an enlarged view of the welded portion 201 shown in Figure 2(A). The negative electrode current collector 105 has a bent portion 212 with the first surface 221 on the inside. As shown in Figure 2(D), by not providing the negative electrode active material layer 106 in the bent portion 212 with the first surface 221 on the inside, the vicinity of the bent portion 212 of the negative electrode current collector 105 and the edge 213 of the negative electrode current collector 105 can be overlapped and welded to form the welded portion 201. Also

[0047] Figure 2(D) shows an enlarged view of the welded portion 201 shown in Figure 2(A). The negative electrode current collector 105 has a bent portion 212 with the first surface 221 on the inside. As shown in Figure 2(D), by not providing the negative electrode active material layer 106 in the bent portion 212 with the first surface 221 on the inside, the vicinity of the bent portion 212 of the negative electrode current collector 105 and the edge 213 of the negative electrode current collector 105 can be overlapped and welded to form the welded portion 201. Also

[0048] As shown in Figure 2(D), by not providing the negative electrode active material layer 106 in the bent portion 212 with the first surface 221 on the inside, the vicinity of the bent portion 212 of the negative electrode current collector 105 and the edge 213 of the negative electrode current collector 105 can be overlapped and welded to form the welded portion 201. Also Figure 2(D) shows an enlarged view of the welded portion 201 shown in Figure 2(A). The negative electrode current collector 105 has a bent portion 212 with the first surface 221 on the inside. As shown in Figure 2(D), by not providing the negative electrode active material layer 106 in the bent portion 212 with the first surface 221 on the inside, the vicinity of the bent portion 212 of the negative electrode current collector 105 and the edge 213 of the negative electrode current collector 105 can be overlapped and welded to form the welded portion 201. Also By forming the welded portion 201, it is possible to suppress the collapse of the zigzag structure of the negative electrode current collector 105. In addition, by connecting the negative electrode lead 145 to the welded portion 201, the internal resistance of the negative electrode 115 can be reduced. Therefore, the cycle characteristics of the secondary battery 100 can be improved, and the charge / discharge capacity can be increased.

[0049] In addition, in the negative electrode current collector 105 included in the negative electrode 115, it is preferable that the bent portion 212 and the bent portion 211 are parallel or substantially parallel. By the bent portion 212 and the bent portion 211 being parallel or substantially parallel to each other, the secondary battery 100 can be easily bent at least in the axial direction perpendicular to the bent portion 212 or the bent portion 211.

[0050] For example, when observing the plate-like member A from a direction perpendicular to the flat plate-like portion (hereinafter referred to as the flat plate-like portion A) adjacent to the bent portion (hereinafter referred to as the bent portion A) of the plate-like member A, a part of the bent portion A can be recognized as one side (hereinafter referred to as side A) of the plate-like member A. Further, for example, when observing the plate-like member B from a direction perpendicular to the flat plate-like portion (hereinafter referred to as the flat plate-like portion B) adjacent to the bent portion (hereinafter referred to as the bent portion B) of the plate-like member B, a part of the bent portion B can be recognized as one side ( hereinafter referred to as side B) of the plate-like member B. In this specification, the bent portion A and the bent portion B being parallel means that side A and side B are parallel. Note that the above-mentioned plate-like member B may be the same as the plate-like member A or another plate-like member.

[0051] Also, as described above, in this specification, "parallel" means a state in which two straight lines are arranged at an angle of -10° or more and 10 ° or less. Therefore, for the bent portion A and the bent portion B to be parallel means that side A and side B are arranged at an angle of -10° or more and 10° or less. state.

[0052] Also, as described above, in this specification, "substantially parallel" means a state in which two straight lines are arranged at an angle of -30° or more and 3 0° or less. Therefore, for the bent portion A and the bent portion B to be substantially parallel means that side A and side B are arranged at an angle of -30° or more and 30°C or less. state.

[0053] Fig. 3(D) shows a state of observing the negative electrode 115 from a direction perpendicular to the flat portion of the zigzag negative electrode current collector 105. In Fig. 3(D), a part of the bent portion 211 can be recognized as one side 281 of the negative electrode current collector 105. Also, in Fig. 3(D), a part of the bent portion 212 can be recognized as one side 282 of the negative electrode current collector 105. Fig. 3(D) shows a state of observing the negative electrode 115 from a direction perpendicular to the flat portion of the zigzag negative electrode current collector 105. In Fig. 3(D), a part of the bent portion 211 can be recognized as one side 281 of the negative electrode current collector 105. Also, in Fig. 3(D), a part of the bent portion 212 can be recognized as one side 282 of the negative electrode current collector 105. Fig. 3(D) shows a state of observing the negative electrode 115 from a direction perpendicular to the flat portion of the zigzag negative electrode current collector 105. In Fig. 3(D), a part of the bent portion 211 can be recognized as one side 281 of the negative electrode current collector 105. Also, in Fig. 3(D), a part of the bent portion 212 can be recognized as one side 282 of the negative electrode current collector 105. Fig. 3(D) shows a state of observing the negative electrode 115 from a direction perpendicular to the flat portion of the zigzag negative electrode current collector 105. In Fig. 3(D), a part of the bent portion 211 can be recognized as one side 281 of the negative electrode current collector 105. Also, in Fig. 3(D), a part of the bent portion 212 can be recognized as one side 282 of the negative electrode current collector 105. be recognized.

[0054] Next, the positive electrode 111 will be described with reference to Figs. 3(A) and (B).

[0055] In the positive electrode 111, the positive electrode active material layer 102 is provided only on one surface of the positive electrode current collector 101. The positive electrode current collector 101 is bent in a zigzag manner similar to the negative electrode current collector 105 and the separator 108, forming a plurality of bent portions. In the positive electrode 111, the positive electrode active material layer 102 is provided only on one surface of the positive electrode current collector 101. The positive electrode current collector 101 is bent in a zigzag manner similar to the negative electrode current collector 105 and the separator 108, forming a plurality of bent portions. In the positive electrode 111, the positive electrode active material layer 102 is provided only on one surface of the positive electrode current collector 101. The positive electrode current collector 101 is bent in a zigzag manner similar to the negative electrode current collector 105 and the separator 108, forming a plurality of bent portions.

[0056] As shown in Fig. 3(A), the positive electrode current collector 101 has a bent portion with the fourth surface 224 on the inside. It has 252. When the positive electrode current collector 101 has the bent portion 252, the bent portion 252 is preferably parallel or substantially parallel to the bent portion 211 of the negative electrode current collector 105. Moreover, if the bent portion 252 and the bent portion 251 are parallel, it is more preferable. By adopting the above configuration, the secondary battery 100 can be easily bent.

[0057] Also, in the positive electrode current collector 101 of the positive electrode 111, the bent portion 252 and the bent portion 251 are parallel or substantially parallel to each other, so that the secondary battery 100 can be easily bent in the axial direction perpendicular to the bent portion 2 51 or the bent portion 252, which is preferable.

[0058] Fig. 3(C) shows a state of observing the positive electrode 111 from a direction perpendicular to the flat plate-like portion of the zigzag positive electrode current collector 101. In Fig. 3(C), a part of the bent portion 251 can be recognized as one side 283 of the positive electrode current collector 101. Also, in Fig. 3(C), a part of the bent portion 252 can be recognized as one side 284 of the positive electrode current collector 101.

[0059]

[0059] Also, Fig. 3(B) shows a cross-sectional perspective view of the portion surrounded by the dotted line 250 in Fig. 3(A). The positive electrode current collector 101 has a third surface 223 on which the positive electrode active material layer 102 is provided, a fourth surface 224 on which the positive electrode active material layer 102 is not provided, and a bent portion 251 with the third surface 223 on the inside. Also, in Fig. 3(B), the side 281 described with reference to Fig. 3(D) is indicated by double-headed arrows 2 91, and the side 283 described with reference to Fig. 3(C) is indicated by double-headed arrows 293.

[0060]

[0060] As shown in FIG. 3(B), double-headed arrow 291 and double-headed arrow 293 are parallel or substantially parallel, that is, by the fact that the bent portion 251 of the positive electrode current collector 101 is parallel or substantially parallel to the bent portion 211 of the negative electrode current collector 105, the secondary battery 100 can be bent as shown in FIG. 5 in the axial direction perpendicular to at least the bent portion 251 of the positive electrode current collector 101 or in the axial direction perpendicular to the bent portion 211 of the negative electrode current collector 105. The positive electrode current collector 101 is connected to the positive electrode lead 141 at its end. As shown in FIGS. 2 and 3, in the negative electrode 115, it is preferable to have a plurality of negative electrode active material layers 106 on one surface of one negative electrode current collector 105 and provide a bent portion between the plurality of negative electrode active material layers 106. Also, in the positive electrode 111, it is preferable to have a plurality of positive electrode active material layers 102 on one surface of one positive electrode current collector 101 and provide a bent portion between the plurality of positive electrode active material layers 102. In the present embodiment, an example in which the number of bent portions of each of the positive electrode current collector 101, the negative electrode current collector 105, and the separator 108 is 5 is shown, but the present embodiment is not limited thereto. The number of bent portions of the positive electrode current collector 101, the negative electrode current collector 105, and the separator 108 may be 1 or more and 4 or less, or 6 or more, respectively.

[0061] The larger the area of the positive electrode active material layer 102 in the positive electrode 111 and the area of the negative electrode active material layer 106 in the negative electrode 115, the more the capacity of the secondary battery 100 can be increased, which is preferable. Also, the more the number of bent portions of the positive electrode current collector 101 or the negative electrode current collector 105, the more

[0062]

[0063]

[0064] ​​​​​​​​​​It is preferable that the battery 100 can be miniaturized.

[0065] In addition, with the configuration described above, compared with a secondary battery having a structure in which a plurality of electrodes each having one active material layer provided on one current collector are stacked, the number of components can be reduced and manufacturing can be facilitated. Also, during manufacturing, it is possible to easily align the positions of the positive electrode and the negative electrode. Therefore, when miniaturization of the secondary battery is required, for example, even when manufacturing a secondary battery that is difficult to manufacture by hand, the secondary battery 100 is easy to manufacture. Therefore, it can also be said that the secondary battery 100 is a secondary battery that is easy to mass-produce.

[0066] In FIGS. 2 to 5, regarding the negative electrode current collector 105 of the negative electrode 115, a first region 231 and a second region 232 divided by a bent portion 211 with the second surface 222 on the inner side are shown, but the present embodiment is not limited to this. Two regions divided by a bent portion 212 with the first surface 221 on the inner side may be connected. Also, regarding the positive electrode current collector 101 of the positive electrode 111, a configuration in which two regions divided by a bent portion 251 with the third surface 223 on the inner side are connected may be used. Also, regarding the positive electrode current collector 101, a configuration in which two regions divided by a bent portion 252 with the fourth surface 224 on the inner side are connected may be used.

[0067] In this specification, the positive electrode and the negative electrode may be used by appropriately swapping them as needed.

[0068] [2. Modification Example 1] Next, another configuration of the positive electrode 111 will be described with reference to FIGS. 6(A) and (B). The negative electrode 115, Regarding the separator 108, the exterior body 110, and the electrolytic solution 109, reference can be made to the description of the basic configuration of the secondary battery 100 described above.

[0069] Fig. 6(A) shows a perspective view of the secondary battery 100, and Fig. 6(B) shows a cross-sectional view of the secondary battery 100 along the X7- X8 line.

[0070] When the positive electrode lead 141 and the negative electrode lead 145 are respectively attached to the exterior body 110 in opposite directions as in the secondary battery 100 shown in Fig. 6(A), the connection between the positive electrode lead 141 and the positive electrode 111 may be the same as the connection between the negative electrode lead 145 and the negative electrode 115. That is, as shown in Fig. 6(B), the bent portion of the positive electrode current collector 101 may be connected by the welding portion 261. This can suppress the collapse of the zigzag structure of the positive electrode current collector 101.

[0071] Also, the positive electrode lead 141 may be connected to the welding portion 261. This can reduce the internal resistance of the positive electrode 11 1. Therefore, the cycle characteristics of the secondary battery 100 can be improved , and the charge / discharge capacity can also be increased.

[0072] As described above, in the secondary battery 100 according to one aspect of the present invention, the lead electrodes can be freely arranged, so the degree of design freedom is high. Therefore, the degree of design freedom of products using the secondary battery according to one aspect of the present invention can be increased. Also, the productivity of products using the secondary battery according to one aspect of the present invention can be increased.

[0073] Also, either one of the positive electrode 111 and the negative electrode 115 does not have to be bent in a zigzag as shown in Figs. 2 to 6. For example, the positive electrode 111a and the negative electrode 115a of the secondary battery 100 shown in Fig. 7​​​​ It may be flat like the positive electrode 111b. The positive electrode 111a has a positive electrode active material layer 102 provided on one surface of the positive electrode current collector 101. The positive electrode active material layer 102 faces the negative electrode active material layer 10 6 with the separator 108a interposed therebetween. Also, the positive electrode 111b has a positive electrode active material layer 102 provided on both surfaces of the positive electrode current collector 10 1. The positive electrode active material layer 102 faces the negative electrode active material layer 106 with the separator 108b interposed therebetween.

[0074] Also, the separator 108 does not have to be folded in a zigzag manner. For example, like the separator 108a and the separator 108b included in the secondary battery 100 shown in FIG. 7, it may be in a shape that sandwiches the positive electrode. The separator 108a sandwiches the positive electrode 111a, and the separator 108b sandwiches the positive electrode 111b. By sandwiching the separator 108 with 111a, it is possible to more surely prevent an internal short circuit from occurring in the secondary battery 100.

[0075] [3. Modification Example 2] Next, another configuration of the negative electrode 115 will be described with reference to FIGS. 8 and 9. For the positive electrode 111, the separator 108, the exterior body 110, and the electrolytic solution 109, reference can be made to the above description.

[0076] FIG. 8(A) shows a cross-sectional view of the secondary battery 100. In the secondary battery 100, the negative electrode 115 has a negative electrode current collector 105, a negative electrode active material layer 106, and a friction layer 107. Also, the negative electrode current collector 105 is folded in a zigzag manner and has a plurality of bent portions.

[0077] In the negative electrode 115 shown in FIG. 8(A), an enlarged view of the portion 115b surrounded by a dotted line is shown in FIG. 8( It is shown in FIG. 8(B). The negative electrode current collector 105 has a first surface 221 and a second surface 222, and is bent with the second surface 2 22 on the inside to form a bent portion 211. The negative electrode active material layer 106 is provided on the first surface 221, and the friction layer 107 is provided on the second surface 222.

[0078] An enlarged view of a portion 202 surrounded by a dotted line of the portion 115b shown in FIG. 8(B) is shown in FIG. 8(C). The second surface 222 of the negative electrode current collector 105 is divided into a first region 231 and a second region 232 with the bent portion 211 as a boundary. Also, the first region 231 and the second region 232 face each other. The friction layer 107 is provided only in the first region 231 and is not provided in the second region 232.

[0079] With this configuration, the friction layer 107 provided in the first region 231 contacts the second region As will be described later, since a material with a small frictional force acting on the contact surface with other substances is used for the friction layer 107, with this configuration in which the friction layer 107 and the second region 232 are in contact, the negative electrode current collector 105 can be made more deformable.

[0080] When the coefficient of static friction between the friction layer 107 and the second region 232 is smaller than the coefficient of static friction between the first region 231 and the second region 232, with this configuration, the negative electrode current collector 105 can be made more deformable, which is preferable.

[0081] Note that the coefficient of static friction in this specification and the like can be obtained by measurement by the inclination method or measurement using a linear sliding type tester.

[0082] Also, the coefficient of static friction in this specification and the like can be obtained as follows. First, the surface Place Sample A and Sample B on a flat glass plate placed horizontally. Then place a flat plate and a weight on top of them. Fix Sample A, attach a load testing machine to Sample B, and pull it horizontally at, for example, about 1 mm / second using the load testing machine. Measure the maximum value of the load until Sample B moves 1 cm, and regard this measured value as the maximum frictional force. Let the maximum frictional force be F, and let the vertical resistance force exerted on Sample A by the flat plate, the weight, and the load of Sample B be N. Then, the static friction coefficient μ between Sample A and Sample B can be obtained by μ = N / F. Note that the static friction coefficient in this specification, etc., can also be measured even when the electrode to be measured is placed on a flat and horizontal glass plate and Sample B is sandwiched between Sample A above and below.

[0083] Note that when there is a liquid between Sample A and Sample B, the static friction coefficient may become smaller. When measuring the static friction coefficient for a friction surface where there may be an electrolytic solution when used as a secondary battery, it is more preferable to supply the electrolytic solution between Sample A and Sample B and then perform the measurement. Also, in a secondary battery, for example, when using a gel-like electrolytic solution, etc.,

[0084] the electrolytic solution may be difficult to supply to the friction surface. When measuring the static friction coefficient for an electrode used in such a secondary battery, it is not necessary to supply the electrolytic solution between Sample A and Sample B.

[0085] In FIGS. 8(A), (B), and (C), an example where the negative electrode 115 has a friction layer 107 is shown, but one aspect of the present invention is not limited to this, and the positive electrode 111 may have a friction layer 107.

[0086] Also, in FIGS. 8(A), (B), and (C), a part of the second surface 222 of the negative electrode current collector 105 is​​​​​​​ Although an example in which the friction layer 107 is provided only in the first region 231 has been shown, one aspect of the present invention is not limited to this and, for example, the entire second surface 222 of the negative electrode current collector 105 and also the entire fourth surface 224 of the positive electrode current collector 10 1 that does not have the positive electrode active material layer 102 may be provided with the friction layer 107 as well.

[0087] For example, in the cross-sectional view of the secondary battery 100 shown in FIG. 9(A), the positive electrode 111 and the negative electrode 115 both have the friction layer 107. With this configuration, both the positive electrode current collector 101 and the negative electrode current collector 1 05 can be made more deformable. Therefore, when the secondary battery 100 is curved both the positive electrode 111 and the negative electrode 115 can be made to deform easily following the deformation of the entire secondary battery 100.

[0088] In the negative electrode 115 shown in FIG. 9(A), an enlarged view of the portion 115c surrounded by the dotted line is shown in FIG. 9( B). The negative electrode current collector 105 has a first surface 221 and a second surface 222, and the second surface 2 22 is bent with the inner side as the inside, forming a bent portion 211. The negative electrode active material layer 106 is provided on the first surface 221, and the friction layer 107 is provided on the second surface 222.

[0089] An enlarged view of the portion surrounded by the dotted line of the portion 115c shown in FIG. 9(B) is shown in FIG. 9(D). The second surface 222 of the negative electrode current collector 105 is divided into a first region 231 and a second region 232 with the bent portion 211 as a boundary, and the first region 231 and the second region 232 face each other. The friction layer 107 is provided on both the first region 231 and the second region 232.

[0090] The coefficient of static friction between the friction layer 107 and the friction layer 107 is the friction layer 107 and the first region 23 When it is smaller than the coefficient of static friction between the first or second region 232, by adopting this configuration, the negative electrode current collector 105 can be made more deformable, which is preferable.

[0091] In addition, when the friction layer 107 is made of a material having no conductivity, in the negative electrode current collector 105 if the friction layer 107 is provided near the bent portion 212 and the welded portion 201, it becomes difficult to connect the first region 231 and the second region 232 of the negative electrode current collector 1 05. Therefore, as shown in FIGS. 8(A), (B) and FIGS. 9(A), (B), in the negative electrode current collector 105, it is preferable that there is no friction layer 107 near the bent portion 212 and the welded portion 201. On the other hand, when the friction layer 107 is made of a conductive material, in the negative electrode current collector 105 even if the friction layer 107 is provided near the bent portion 212 and the welded portion 201, the first region 231 and the second region 232 of the negative electrode current collector 1

[0092] 05 can be connected. Therefore, as shown in the enlarged view of the welded portion 201 in FIG. 9(C), the friction layer 107 may be provided near the bent portion 212 and the welded portion 201. On the other hand, when the friction layer 107 is made of a conductive material, in the negative electrode current collector 105 even if the friction layer 107 is provided near the bent portion 212 and the welded portion 201, the first region 231 and the second region 232 of the negative electrode current collector 1 (C) of the welded portion 201, as shown in the enlarged view, the friction layer 107 may be provided near the bent portion 212 and the welded portion 201. can be connected. Therefore, as shown in the enlarged view of the welded portion 201 in FIG. 9(C), the friction layer 107 may be provided near the bent portion 212 and the welded portion 201.

[0093] [4. Modified Example 3] Next, another configuration of the secondary battery 100 will be described with reference to FIG. 10.

[0094] The secondary battery 100 shown in FIG. 10 includes a positive electrode 111, a negative electrode 115, a separator 108, and a gel electrolyte 109a. The positive electrode 111 includes a positive electrode current collector 101 and a positive electrode active material layer 102. The negative electrode 115 includes a negative electrode current collector 105 and a negative electrode active material layer 106. The positive electrode current collector 101, the negative electrode current collector 105, and the separator 108 are folded in a zigzag pattern. The positive electrode 111 has a positive electrode current collector 101 and a positive electrode active material layer 102. The negative electrode 115 has a negative electrode current collector 105 and a negative electrode active material layer 106. The positive electrode current collector 101, the negative electrode current collector 105, and the separator 108 are folded in a zigzag pattern. The positive electrode current collector 101, the negative electrode current collector 105, and the separator 108 are folded in a zigzag pattern. , each having a plurality of bending portions. Also, the positive electrode active material layer 102 and the negative electrode active material layer 10 6 face each other via the separator 108 and the gel electrolyte 109a. Also, the positive electrode current collector 101 is connected to the positive electrode lead 141. Further, the negative electrode current collector 105 is connected to the negative electrode lead 145.

[0095] When the gel electrolyte 109a is provided between the positive electrode 111 and the negative electrode 115, it becomes easy to keep the distance between the positive electrode active material layer 102 and the negative electrode active material layer 106 constant. Therefore, it becomes easy to keep the rate of the battery reaction between the positive electrode 111 and the negative electrode 115 constant . Therefore, with this configuration, when the secondary battery 100 is bent, by keeping the distance between the positive electrode active material layer 102 and the negative electrode active material layer 106 constant, it is possible to prevent the rate of the battery reaction between the positive electrode 111 and the negative electrode 115 from varying, and suppress the deterioration of the capacity and cycle characteristics of the secondary battery 100 .

[0096] [5. Modification Example 4] Using FIGS. 11 to 23, further modification examples of the secondary battery 100 are shown. Note that, regarding the positive electrode 111, negative electrode 115, separator 108, exterior body 110, electrolyte 10 9, etc. shown in FIGS. 11 to 23, when not particularly explained, the descriptions of modification examples 1 to 3 can be referred to.

[0097] In FIG. 11(A), a modification example of the cross-sectional view of the secondary battery 100 shown in FIG. 1 along the X1-X2 line is shown, and in FIG. 11(B), a modification example of the cross-sectional view of the secondary battery 100 along the X3-X4 line is shown.

[0098] As shown in FIGS. 11(A) and (B), in some cases, in the negative electrode 115, the negative electrode current collector The first surface and the second surface of the negative electrode current collector 105 do not have to be connected by welding. Even if the welded portion 201 is not included, the negative electrode tab 105 is connected to the negative electrode lead 14. 5 can be connected.

[0099] The negative electrode tab is a portion of the negative electrode on which an active material is formed for electrically connecting to the negative electrode lead. Similarly, the positive electrode tab refers to the part of the positive electrode that has an area that is not covered by the positive electrode lead. The term "active material" refers to a portion having an area where no active material is formed, for electrical connection to the active material.

[0100] FIG. 12A shows another modified cross-sectional view of the secondary battery 100 taken along line X1-X2 in FIG. As an example, FIG. 12B shows another modified example of a cross-sectional view of the secondary battery 100 taken along line X3-X4. vinegar.

[0101] As shown in FIGS. 12(A) and 12(B), in some cases, the negative electrode current collector 105 does not have a bent portion corresponding to the bent portion 212 shown in FIG. If a plurality of folded negative electrode current collectors 105 are connected by welded parts 201, A connection to the negative lead 145 can be made at the contact portion 201 .

[0102] FIG. 13A shows another modified cross-sectional view of the secondary battery 100 taken along line X1-X2 in FIG. FIG. 14 shows another modified example of a cross-sectional view taken along line X3-X4. 13(A) is an enlarged view of a portion 115a enclosed by a dotted line in FIG.

[0103] As shown in FIGS. 13(A), (B) and 14, in some cases, in the negative electrode 115, The negative electrode current collector 105 has a bent portion corresponding to the bent portion 211 shown in FIG. It is not necessary. The surfaces of the two negative electrode current collectors 105 that do not have the negative electrode active material layer 106 (the first second surface 222 including the region 231 and the second surface 222 including the second region 232) may be connected at the welding portion 211a.

[0104] Fig. 15(A) shows another modified example of the cross-sectional view of the secondary battery 100 taken along the X1-X2 line shown in Fig. 1, and Fig. 15(B) shows another modified example of the cross-sectional view of the secondary battery 100 taken along the X3-X4 line. shown.

[0105] As shown in Figs. 15(A) and (B), in some cases, in the positive electrode 111, the positive electrode current collector 101 may not have a bent portion corresponding to the bent portion 252 shown in Fig. 3. The surfaces of the two positive electrode current collectors 101 that do not have the positive electrode active material layer 102 may be connected at the welding portion 252 a. shown.

[0106] Fig. 16(A) shows another modified example of the cross-sectional view of the secondary battery 100 taken along the X1-X2 line shown in Fig. 1, and Fig. 16(B) shows another modified example of the cross-sectional view of the secondary battery 100 taken along the X3-X4 line. shown.

[0107] As shown in Figs. 16(A) and (B), in the positive electrode 111, the positive electrode current collector 101 may not have a bent portion corresponding to the bent portion 251 described in Fig. 3(B). The surfaces of the two positive electrode current collectors 101 that do not have the positive electrode active material layer 102 may be connected at the welding portion 251a. shown. shown.

[0108] Fig. 17 shows a modified example of the cross-sectional view of the secondary battery 100 taken along the X7-X8 line shown in Fig. 6(A). shown.

[0109] As shown in FIG. 17, when the positive electrodes 111a and 111b are flat plates, at the negative electrode 115 even if the first surface and the second surface of the negative electrode current collector 105 are not connected. Even when the negative electrode current collector 105 has no welding portion, at the negative electrode tab provided at the end, the negative electrode lead 145 can be connected.

[0110] FIG. 18 shows another modified example of the cross-sectional view taken along the X7-X8 line of the secondary battery 100 shown in FIG. 6(A). is shown.

[0111] As shown in FIG. 18, when the positive electrodes 111a and 111b are flat plates, at the negative electrode 115 even if the negative electrode current collector 105 does not have a bent portion corresponding to the bent portion 212 shown in FIG. 2. If a configuration is such that a plurality of two-fold negative electrode current collectors 105 are connected by a welding portion 201, the negative electrode lead 145 can be connected by the welding portion 201.

[0112] FIG. 19 shows another modified example of the cross-sectional view taken along the X7-X8 line of the secondary battery 100 shown in FIG. 6(A). is shown.

[0113] As shown in FIG. 19, even when the positive electrodes 111a and 111b are flat plates, at the negative electrode 115, the negative electrode current collector 105 may not have the bent portion 211 shown in FIG. 2. A configuration may be such that surfaces of two negative electrode current collectors 105 that do not have the negative electrode active material layer 106 are connected by a welding portion 211a.

[0114] FIG. 20 shows another modified example of the cross-sectional view taken along the X7-X8 line of the secondary battery 100 shown in FIG. 6(A). is shown.

[0115] The positive electrode 111 may have a shape that is neither a zigzag nor a flat plate. The positive electrode 1 shown in FIG. 20 In part of the positive electrode current collector 101, the positive electrode active material layer 102 is provided on both sides, and the positive electrode In another part of the current collector 101, the positive electrode active material layer 102 is provided only on one side. Such a configuration in which the positive electrode 111 is connected by the welding part 261 may be used.

[0116] Figs. 21 to 23 show another modified example of the secondary battery 100 having the friction layer 107.

[0117] As shown in Fig. 21, only the positive electrode 111 may have the friction layer 107.

[0118] Also, as shown in Fig. 22, in the case where both the positive electrode 111 and the negative electrode 115 have the friction layer 107, the friction layer 107 may be provided in part of each of the positive electrode current collector 101 and the negative electrode current collector 105.

[0119] Also, as shown in Fig. 23, the secondary battery 100 may have a negative electrode 115 having a friction layer 107, a folded positive electrode 111a, and a flat positive electrode 111b.

[0120] [6. Materials] Next, the materials constituting the secondary battery 100 will be described.

[0121] For the positive electrode current collector 101 and the negative electrode current collector 105, metals such as stainless steel, gold, platinum, iron, copper, aluminum or titanium, and alloys of these metals, etc., which have high conductivity and do not alloy with carrier ions such as lithium, can be used. Also, an aluminum alloy added with elements for improving heat resistance such as silicon, titanium, neodymium, scandium, molybdenum, etc. can be used. Also, a metal element that reacts with silicon to form a silicide ​​It may be formed as a simple substance. As the metal element that reacts with silicon to form silicide, zir conium, titanium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, nickel, etc. are available. The current collector can appropriately use shapes such as foil, plate (sheet), net , punching metal, expanded metal, etc. The current collector is preferably one with a thickness of 5 μm or more and 30 μm or less. Also, an undercoat layer may be provided on the surface of the current collector using graphite or the like.

[0122] As the friction layer, a film having conductivity or a film having insulating properties may be used, and an organic film, an inorganic film, a metal film, etc. can be used.

[0123] Examples of the organic film include a resin film or a film formed of a low-molecular compound.

[0124] The resin film is one or more resin materials selected from thermosetting resins such as epoxy resin, acrylic resin, silicone resin, phenol resin, polyester resin, or one or more resin materials selected from thermoplastic resins such as polypropylene , polyethylene, polycarbonate, polystyrene, polyamide, polyether ketone , fluororesin, polyethylene naphthalate, etc. It can also be formed using polyoxymethylene. In particular, fluororesin has high slidability, such as represented by polytetrafluoro ethylene with a coefficient of static friction of about 0.04 between the same materials, and can improve the slidability of the friction layer, which is preferable. Also, it is preferable that the friction layer does not decompose at the potential of the battery reaction. For example, when the potential of the battery reaction of the negative electrode is low, the fluororesin may undergo reductive decomposition. Therefore, it is preferable to use fluororesin as the friction layer of the positive electrode. Polyether ketone, typified by ether ether ketone (PEEK), is a material that has excellent sliding properties and heat resistance. Since the friction layer has excellent mechanical properties, fatigue resistance, and chemical resistance, the friction layer can have improved sliding properties. Polyparaxylylene resin may also be formed by chemical vapor deposition (CVD). Laxylene resin has excellent sliding properties, heat resistance, and chemical resistance, which improves the sliding properties of the friction layer. This is preferable.

[0125] Self-assembled monolayers (SAMs) are films formed from low molecular weight compounds. A self-assembled monolayer (SAM) may be used. This improves the lubricity of the collector surface and the sliding properties of the electrodes. It is preferable to use a liquid-repellent SAM. Silane coupling agents having fluoroalkyl groups (hereinafter referred to as FA The heated current collector and FAS are enclosed, and the collected material is reacted in a gas phase. It is possible to form a FAS self-assembled monolayer on the surface of a dielectric. A friction layer can be formed on the current collector by evaporating a solid lubricant such as MCCA. good.

[0126] As the inorganic film and the metal film, a material that can be attached to the current collector can be used. In addition, it does not cause the insertion or desorption of lithium ions, and does not undergo alloying / dealloying reactions with lithium. It is particularly preferable to use a material that does not cause such a problem. For example, an inorganic film can be used as a substitute for a solid lubricant. Representative molybdenum disulfide (MoS 2 ), or tungsten disulfide (WS 2)Metal sulfides such as using boron nitride (BN), etc. can improve the slidability of the electrode. Also, the inorganic film may have insulating properties, and silicon oxide, silicon oxynitride, gallium oxide, gallium oxynitride, yttrium oxide, yttrium oxynitride, hafnium oxide, hafnium oxynitride and other oxide insulating films, silicon nitride, aluminum nitride and other nitride insulating films can be used.

[0127] As the metal film, for example, metal materials such as aluminum, gold, platinum, silver, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, or palladium, or alloys containing these metal materials can be used. Also, lanthanum, neodymium, or germanium, etc. may be added to the above metal materials or alloys. Also, alloys containing aluminum such as an alloy of aluminum and titanium, an alloy of aluminum and nickel, an alloy of aluminum and neodymium, an alloy of aluminum, nickel, and lanthanum (Al-Ni-La), etc. (aluminum alloys), and alloys containing silver such as an alloy of silver and copper, an alloy of silver, palladium and copper (also denoted as Ag-Pd-Cu, APC), an alloy of silver and magnesium can be used to form. An alloy containing silver and copper is preferable because of its high heat resistance.

[0128] Also, the friction layer may be a laminated film having two or more of the above-mentioned organic films, inorganic films, and metal films.

[0129] Also, by reducing the surface roughness of the friction layer, the frictional force acting on the contact surface between the surface of the friction layer and another surface in contact with the friction layer can be reduced, which is more preferable. Specifically, the surface of the friction layer ​​​It is preferable that the arithmetic mean roughness Ra on at least a part of the surface is 1 μm or less, and more preferably 0 .5 μm or less. The arithmetic mean roughness Ra of the friction layer can be determined by measurement using a stylus-type surface shape measuring instrument or an atomic force microscope (AFM) or the like.

[0130] Also, the friction layer is preferably difficult to break. For example, when performing a test of applying a tensile stress to cause breakage, it is preferable to use, as the friction layer, a material having an elongation rate of 5% or more immediately before breakage, and it is more preferable to use, as the friction layer, a material having an elongation rate of 10% or more immediately before breakage. Moreover, in some cases, lubricity may be imparted to the surface of the current collector by using a cleavable material as the friction layer.

[0131] Also, in some cases, lubricity may be imparted to the surface of the current collector by using a cleavable material as the friction layer.

[0132] The thicknesses of the positive electrode active material layer 102 and the negative electrode active material layer 106 are preferably in the range of 10 μm or more and 200 μm or less. The positive electrode active material layer 102 and the negative electrode active material layer 106 each have an active material capable of a reversible reaction with a carrier ion such as a lithium ion. By appropriately pulverizing, granulating, and classifying, the average particle size and particle size distribution of the active material can be controlled. The average particle size of the active material is preferably 500 nm or less, more preferably 50 nm or more and 500 nm or less. As the positive electrode active material contained in the positive electrode active material layer 102, a material capable of inserting and extracting lithium ions can be used. For example, a lithium-containing material having an olivine-type crystal structure, a layered rock salt-type crystal structure, or a spinel-type crystal structure can be used.

[0133] As the positive electrode active material contained in the positive electrode active material layer 102, a material capable of inserting and extracting lithium ions can be used. For example, a lithium-containing material having an olivine-type crystal structure, a layered rock salt-type crystal structure, or a spinel-type crystal structure can be used.

[0134] Examples of the lithium-containing material having an olivine-type structure include, for example, the general formula LiMPO 4 (where M is one or more of Fe (II), Mn(II), Co(II), Ni(II)). Representative examples of the general formula LiMPO 4 include LiFePO 4 , LiNiPO 4 , LiCoPO 4 , L iMnPO 4 , LiFe a Ni b PO 4 , LiFe a Co b PO 4 , LiFe a Mn b P O 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 Ni d Co e PO 4 , LiFe c Ni d Mn e PO 4 , Li Ni 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 Co h Mn i PO 4 (f + g + h + i is 1 or less, 0 < f < 1, 0 < g < 1, 0 < h < 1, 0 < i < 1), etc., lithium-containing composite phosphates.

[0135] Examples of the lithium-containing material having a layered rock salt-type crystal structure include, for example, LiCoO2 , Li NiO 2 , LiMnO 2 , Li 2 MnO 3 , LiNi 0.8 Co 0.2 O 2 such as NiCo series (general formula: LiNi x Co 1-x O 2 (0 < x < 1)), LiNi 0.5 Mn 0.5 O 2 such as NiMn series (general formula: LiNi x Mn 1-x O 2 (0 < x < 1)), LiNi 1 / 3 Mn 1 / 3 Co 1 / 3 O 2 such as NiMnCo series (also referred to as NMC. General formula: Li Ni x Mn y Co 1-x-y O 2 (x > 0, y > 0, x + y < 1)) can be mentioned. Further , Li(Ni 0.8 Co 0.15 Al 0.05 )O 2 , Li 2 MnO 3 -LiMO 2 ( M = Co, Ni, Mn) etc. can also be mentioned.

[0136] As lithium-containing materials having a spinel-type crystal structure, for example, LiMn 2 O 4 , L i 1+x Mn 2-x O 4 (0 < x < 2), LiMn 2-x Al x O 4 (0 < x < 2), L iMn 1.5 Ni 0.5 O 4Examples include lithium manganese-containing composite oxides and the like.

[0137] LiMn 2 O 4 Lithium manganese-containing having a spinel-type crystal structure containing manganese such as Composite oxides, a small amount of lithium nickelate (LiNiO 2 or LiNi 1-x M x O 2 (0 <x<1) (M = Co, Al, etc.)) are mixed, there are advantages such as suppressing the elution of manganese and suppressing the decomposition of the electrolytic solution, which is preferable. There are advantages such as suppressing the elution of manganese and suppressing the decomposition of the electrolytic solution, which is preferable.

[0138] Also, as the positive electrode active material, a lithium-containing material represented by the general formula Li (2-j) MSiO 4 (M is one or more of Fe(II), Mn (II), Co(II), Ni(II), and j is 0 or more and 2 or less) can be used. Representative examples of the general formula Li MSiO (2-j) are 4 For example, Li (2-j) FeSiO 4 、Li (2-j) NiSiO 4 、Li (2-j) CoSiO 4 、Li (2-j) MnSiO 4 、Li (2-j) Fe k Ni l SiO 4 、Li (2-j ) Fe k Co l SiO 4 、Li (2-j) Fe k Mn l SiO 4 、Li (2-j) Ni k Co l SiO 4 、Li (2-j)Ni k Mn l SiO 4 (k + l is 1 or less, 0 < k < 1, 0 < l < 1), Li (2-j) Fe m Ni n Co q SiO 4 , Li (2-j) Fe m Ni n Mn q SiO 4 , Li (2-j) Ni m Co n Mn q SiO 4 (m + n + q is 1 or less, 0 < m < 1, 0 < n < 1, 0 < q < 1), Li (2-j) Fe r Ni s Co t Mn u Si O 4 (r + s + t + u is 1 or less, 0 < r < 1, 0 < s < 1, 0 < t < 1, 0 < u < 1), etc. are exemplified.

[0139] Also, as the positive electrode active material, A x M 2 (XO 4 ) 3 (A = Li, Na, Mg, M = Fe, M n, Ti, V, Nb, Al, X = S, P, Mo, W, As, Si) represented by the general formula of nasicon - type compound can be used. As the nasicon - type compound, Fe 2 (MnO 4 ) 3 , Fe 2 (SO 4 ) 3 , Li 3 Fe 2 (PO 4 ) 3 etc. are exemplified. Also, as the positive electrode active material , Li 2 MPO 4 F, Li 2MP 2 O 7 、 Li 5 MO 4 (M = Fe, Mn) general compound represented by the formula, FeF 3 and other perovskite fluorides, TiS 2 , MoS 2 and other metal chalcogenides (sulfides, selenides, tellurides), LiMVO 4 and other inverse spinel type lithium vanadium-containing composite oxides having a crystal structure, vanadium oxide-based compounds ( V 2 O 5 , V 6 O 13 , LiV 3 O 8 etc.), manganese oxides, organic sulfur compounds and other materials can be used.

[0140] The particle size of the positive electrode active material is preferably, for example, 5 nm or more and 100 μm or less.

[0141] Also, as the positive electrode active material, a lithium manganese composite x Mn y M z O w oxide represented by the formula can also be used. Here, the element M is selected from those other than lithium and manganese metal element, or silicon, phosphorus is preferably used, and nickel is more preferably used. Also, x / (y + z) is 0 or more and less than 2, and z is greater than 0, and (y + z) / w is preferably 0.26 or more and less than 0.5. Note that the lithium manganese composite oxide refers to an oxide containing at least lithium and manganese, and chromium, cobalt, aluminum nium, nickel, iron, magnesium, molybdenum, zinc, indium, gallium, copper, titanium, niobium, silicon, and phosphorus, etc. at least one element selected from the group consisting of ​ It may contain. Further, the lithium manganese composite oxide has a layered rock salt-type crystal structure and is preferably such. Further, the lithium manganese composite oxide may have a layered rock salt-type crystal structure and a spinel-type crystal structure. Further, the lithium manganese composite oxide preferably has an average particle diameter of 5 nm or more and 50 μm or less, for example.

[0142] In addition, when the carrier ion is an alkali metal ion other than lithium ion or an alkaline earth metal ion, as the positive electrode active material, in the above lithium compound and lithium manganese-containing composite oxide, an alkali metal (for example, sodium, potassium, etc. ), an alkaline earth metal (for example, calcium, strontium, barium, beryllium, magnesium, etc.) may be used instead of lithium.

[0143] As the negative electrode active material contained in the negative electrode active material layer 106, a material capable of performing a charge-discharge reaction through an alloying / dealloying reaction with lithium can be used.

[0144] Examples of the material capable of performing a charge-discharge reaction through an alloying / dealloying reaction with lithium include, for example, carbon-based materials. Examples of the carbon-based materials include graphite, graphitizable carbon (soft carbon), non-graphitizable carbon (hard carbon), carbon nanotubes, graphene, carbon black, etc. Examples of the graphite include artificial graphite such as mesocarbon microbeads (MCMB), coke-based artificial graphite, pitch-based artificial graphite, etc., and natural graphite such as spheroidized natural graphite.

[0145]

[0146] When lithium ions are inserted into graphite (when forming a lithium-graphite intercalation compound), it shows a potential as low as that of metallic lithium (0.1 V or more and 0.3 V or less vs. Li / Li + ). As a result, lithium-ion secondary batteries can exhibit a high operating voltage. Furthermore, graphite has advantages such as a relatively high capacity per unit volume, small volume expansion, low cost, and higher safety compared to metallic lithium, so it is preferable.

[0147] Also, as a material capable of performing charge and discharge reactions through alloying and dealloying reactions with lithium, for example, materials containing at least one of Ga, Si, Al, Ge, Sn, Pb, Sb, Bi, Ag, Zn, Cd, I n, etc. can be mentioned. Such elements have a larger capacity compared to carbon, and in particular, silicon has a high theoretical capacity of 4200 mAh / g. Materials using such elements include, for example, Mg Si, Mg 2 Si, Mg 2 Ge, Mg 2 Sn, SnS 2 , V 2 Sn 3 , FeSn 2 , CoSn 2 , Ni 3 Sn 2 , Cu 6 Sn 5 , Ag 3 , Ag 3 Sb, , Ni 2 , MnSb, CeSb 3 , LaSn 3 , La 3 , Co 2 Sn 7 , CoSb 3 , InSb , SbSn, etc.

[0148] Also, as the negative electrode active material, SiO, SnO, SnO 2, titanium dioxide, lithium titanate compounds, lithium-graphite intercalation compounds, niobium pentoxide, tungsten oxide, molybdenum oxide, etc. Oxides thereof can be used.

[0149] Also, as the negative electrode active material, Li, which is a complex nitride of lithium and a transition metal 3 having an N-type structure Li 3-x M x N (M = Co, Ni, Cu) can be used. For example, Li 2.6 Co 0.4 N 3 exhibits a large charge-discharge capacity (900 mAh / g, 1890 mAh / cm 3 ) and is preferable. Thus, it is preferable.

[0150] When using a complex nitride of lithium and a transition metal, since lithium ions are contained in the negative electrode active material, it can be combined with materials such as V 2 O 5 , Cr 3 O 8 etc. that do not contain lithium ions as the positive electrode active material, which is preferable. In addition, even when using a material containing lithium ions as the positive electrode active material , by previously desorbing the lithium ions contained in the positive electrode active material, a complex nitride of lithium and a transition metal can be used as the negative electrode active material.

[0151] Also, a material that causes a conversion reaction can be used as the negative electrode active material. For example , transition metal oxides such as cobalt oxide, nickel oxide, and iron oxide that do not undergo an alloying reaction with lithium can be used as the negative electrode active material. As materials that cause a conversion reaction, further , Fe O 2 O 3 , CuO, Cu 2 O, RuO 2 , Cr 2 O 3Oxides such as 0.89 , sulfides such as NiS and CuS, Zn 3 N 2 , Cu 3 N, Ge 3 N 4 nitrides such as 2 , FeP 2 , CoP 3 phosphides such as FeF 3 , BiF 3 fluorides etc. also occur.

[0152] The positive electrode active material layer 102 and the negative electrode active material layer 106 may, in addition to the above-described active materials, have a binder for enhancing the adhesion of the active materials, a conductive aid for enhancing conductivity, etc. .

[0153] As the binder, in addition to typical polyvinylidene fluoride (PVdF), polyimide, polytetra fluoroethylene, polyvinyl chloride, ethylene propylene diene polymer, styrene -butadiene rubber, acrylonitrile-butadiene rubber, fluororubber, polyvinyl acetate , polymethyl methacrylate, polyethylene, nitrocellulose, etc. can be used. .

[0154] As the conductive aid, for example, natural graphite, artificial graphite such as mesocarbon microbeads, carbon fiber etc. can be used. As the carbon fiber, for example, carbon fibers such as mesophase pitch-based carbon fibers, isotropic pitch-based carbon fibers, etc. can be used. Also, as the carbon fiber, car bon nanofibers, carbon nanotubes, etc. can be used. Carbon nanotubes can be produced, for example, by a vapor phase growth method. Also, as the conductive aid, for example carbon black (such as acetylene black (AB)) or carbon materials such as graphene Materials can be used. Also, for example, metals such as copper, nickel, aluminum, silver, and gold powders, metal fibers, conductive ceramic materials, etc. can be used.

[0155] Next, the separator will be described. The separator is placed between the positive electrode and the negative electrode to prevent their contact. The separator has micropores so as not to impede the movement of ions between the positive electrode and the negative electrode. The separator preferably has little change in state according to the environment in which the power storage device is used. It is preferable that there is little change in state even in a high-temperature environment. Even if there is a change in state, the positive electrode and the negative electrode should not come into contact. As the separator, for example, those formed of paper, non-woven fabric, glass fiber, ceramics, or synthetic fibers using nylon (polyamide), vinylon (polyvinyl alcohol-based fiber), polyester, acrylic, polyolefin, polyurethane, etc. can be used. The thickness of the separator is preferably 10 μm or more and 70 μm or less. It is preferable to process the separator into a bag shape and place it so as to wrap either the positive electrode 111 or the negative electrode 115. For example, by folding the separator 108 in half so as to sandwich the negative electrode 115 and sealing it outside the region overlapping the negative electrode 115, the negative electrode 115 can be surely carried in the separator 10

[0156] 8. Then, the negative electrode 115 wrapped by the separator 108 and the positive electrode 111 are alternately laminated and arranged so that they are surrounded by the exterior body 110 to fabricate the secondary battery 100. (polyamide), vinylon (polyvinyl alcohol-based fiber), polyester, acrylic, polyolefin, polyurethane, etc. can be used. The thickness of the separator is preferably 10 μm or more and 70 μm or less. It is preferable to process the separator into a bag shape and place it so as to wrap either the positive electrode 111 or the negative electrode 115. For example, by folding the separator 108 in half so as to sandwich the negative electrode 115 and sealing it outside the region overlapping the negative electrode 115, the negative electrode 115 can be surely carried in the separator 10

[0157] 8. Then, the negative electrode 115 wrapped by the separator 108 and the positive electrode 111 are alternately laminated and arranged so that they are surrounded by the exterior body 110 to fabricate the secondary battery 100. For example, by folding the separator 108 in half so as to sandwich the negative electrode 115 and sealing it outside the region overlapping the negative electrode 115, the negative electrode 115 can be surely carried in the separator 10 8. And the secondary battery 100 may be fabricated by alternately laminating the negative electrode 115 wrapped by the separator 108 and the positive electrode 111 and arranging them so that they are surrounded by the exterior body 110. 8 and the positive electrode 111 and arranging them so that they are surrounded by the exterior body 110. Next, the electrolyte 109 will be described. The electrolyte 109 transports at least carrier ions. 8.

[0158] Next, the electrolyte 109 will be described. The electrolyte 109 transports at least carrier ions. Use materials that are capable of this. For example, when the carrier ion is a lithium ion, use a material having lithium ions. Representative examples of materials capable of transporting lithium ions include LiPF 、LiClO 、LiAsF 6 、LiBF 4 、LiAlCl 6 、LiSCN、LiBr、LiI、Li 4 SO 4 、Li B 2 Cl 4 、Li 2 B 10 C 10 l 2 、LiCF 12 SO 、LiC 12 F 3 SO 3 、LiC(CF 4 SO 9 、LiC( 3 C 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 S O 2 )、LiN(C 2 F 5 SO 2 ) 2 and other lithium salts. These materials may be used alone or in any combination and ratio of two or more of them. Moreover, when the carrier ion is an alkali metal ion or an alkaline earth metal ion other than a lithium ion, as the positive electrode active material, the above lithium compound and lithium-containing composite phosphate and may be used.

[0159] In the lithium-containing complex silicate, lithium may be replaced with a carrier such as an alkali metal (e.g., sodium or potassium, etc.), an alkaline earth metal (e.g., calcium, strontium, barium, beryllium, magnesium, etc.). A compound obtained by such replacement may be used.

[0160] As the solvent contained in the electrolytic solution 109, a material in which carrier ions can move is used. The solvent is preferably an aprotic organic solvent. For example, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate, chloroethylene carbonate, vinyl carbonate, γ-butyrolactone, γ-valerolactone, dimethyl carbonate ( DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), methyl acetate, methyl acetate, methyl butyrate, 1,3-dioxane, 1,4-dioxane, dimethoxy ethane (DME), dimethyl sulfoxide, diethyl ether, methyl diglyme, acetonitrile, benzonitrile, tetrahydrofuran, sulfolane, sultone, etc. are available and one of these or a combination of two or more of these can be used in any combination and ratio. It is possible.

[0161] A polymer may be added to the electrolytic solution 109 to make it gel-like. By making the electrolytic solution 109 gel-like, the safety against leakage and the like is enhanced. Also, thinning and weight reduction of the secondary battery are possible. As the polymer that can make the electrolytic solution 109 gel-like, for example, polyalkylene oxide-based, polyacrylonitrile-based, polyvinylidene fluoride-based, polyacrylate -based, polymethacrylate-based polymers can be used. In this specification and the like, For example, a polyvinylidene fluoride-based polymer means a polymer containing polyvinylidene fluoride, and includes poly(vinylidene fluoride - hexafluoropropylene) copolymer and the like. The formed polymer may have a porous shape. By using FT-IR (Fourier transform infrared spectrophotometer) or the like, the above-mentioned polymer can be qualitatively analyzed. For example, a polyvinylidene fluoride-based polymer has an absorption indicating a C-F bond in the spectrum obtained by FT-IR. Also, a polyacrylonitrile-based polymer has an absorption indicating a C≡N bond in the spectrum obtained by FT-IR. Moreover, by using one or more ionic liquids (room temperature molten salts) that are flame-retardant and hardly volatile as the solvent contained in the electrolytic solution 109, even if the internal temperature of the secondary battery rises due to internal short circuit, overcharge, etc., rupture and ignition of the secondary battery can be prevented. An ionic liquid consists of a cation and an anion, and includes an organic cation and an anion. Examples of the organic cation used in the electrolytic solution include aliphatic onium cations such as quaternary ammonium cations, tertiary sulfonium cations, and quaternary phosphonium cations, and aromatic cations such as imidazolium cations and pyridinium cations. Also, examples of the anion used in the electrolytic solution include monovalent amide-based anions, monovalent methide-based anions, fluorosulfonic acid anions, perfluoroalkylsulfonic acid anions, tetrafluoroborate, perfluoroalkylborate, hexafluorophosphate, or perfluoroalkylphosphate.

[0162] By using FT-IR (Fourier transform infrared spectrophotometer) or the like, the above-mentioned polymer can be qualitatively analyzed. For example, a polyvinylidene fluoride-based polymer has an absorption indicating a C-F bond in the spectrum obtained by FT-IR. Also, a polyacrylonitrile-based polymer has an absorption indicating a C≡N bond in the spectrum obtained by FT-IR. Moreover, by using one or more ionic liquids (room temperature molten salts) that are flame-retardant and hardly volatile as the solvent contained in the electrolytic solution 109, even if the internal temperature of the secondary battery rises due to internal short circuit, overcharge, etc., rupture and ignition of the secondary battery can be prevented.

[0163] An ionic liquid consists of a cation and an anion, and includes an organic cation and an anion. Examples of the organic cation used in the electrolytic solution include aliphatic onium cations such as quaternary ammonium cations, tertiary sulfonium cations, and quaternary phosphonium cations, and aromatic cations such as imidazolium cations and pyridinium cations. Also, examples of the anion used in the electrolytic solution include monovalent amide-based anions, monovalent methide-based anions, fluorosulfonic acid anions, perfluoroalkylsulfonic acid anions, tetrafluoroborate, perfluoroalkylborate, hexafluorophosphate, or perfluoroalkylphosphate. Moreover, by using one or more ionic liquids (room temperature molten salts) that are flame-retardant and hardly volatile as the solvent contained in the electrolytic solution 109, even if the internal temperature of the secondary battery rises due to internal short circuit, overcharge, etc., rupture and ignition of the secondary battery can be prevented. An ionic liquid consists of a cation and an anion, and includes an organic cation and an anion. Examples of the organic cation used in the electrolytic solution include aliphatic onium cations such as quaternary ammonium cations, tertiary sulfonium cations, and quaternary phosphonium cations, and aromatic cations such as imidazolium cations and pyridinium cations. Also, examples of the anion used in the electrolytic solution include monovalent amide-based anions, monovalent methide-based anions, fluorosulfonic acid anions, perfluoroalkylsulfonic acid anions, tetrafluoroborate, perfluoroalkylborate, hexafluorophosphate, or perfluoroalkylphosphate. Moreover, by using one or more ionic liquids (room temperature molten salts) that are flame-retardant and hardly volatile as the solvent contained in the electrolytic solution 109, even if the internal temperature of the secondary battery rises due to internal short circuit, overcharge, etc., rupture and ignition of the secondary battery can be prevented. An ionic liquid consists of a cation and an anion, and includes an organic cation and an anion. Examples of the organic cation used in the electrolytic solution include aliphatic onium cations such as quaternary ammonium cations, tertiary sulfonium cations, and quaternary phosphonium cations, and aromatic cations such as imidazolium cations and pyridinium cations. Also, examples of the anion used in the electrolytic solution include monovalent amide-based anions, monovalent methide-based anions, fluorosulfonic acid anions, perfluoroalkylsulfonic acid anions, tetrafluoroborate, perfluoroalkylborate, hexafluorophosphate, or perfluoroalkylphosphate.

[0164] In addition, the electrolyte 109 preferably contains little particulate dust and elements other than the constituent elements of the electrolyte (hereinafter simply referred to as "impurities" ").) and is highly purified. Specifically, the weight ratio of impurities to the electrolyte is preferably 1% or less, more preferably 0.1% or less, and even more preferably 0. 01% or less.

[0165] Additives such as vinylene carbonate, propane sultone (PS), tert-butylbenzene (TBB), fluoroethylene carbonate (FEC), and LiBOB (lithium bis(oxalato)borate) may be added to the electrolyte 109. The concentration of the additive may be, for example, 0.1 wt% or more and 5 wt% or less based on the total amount of the solvent.

[0166] In addition, a solid electrolyte containing an inorganic material such as a sulfide-based or oxide-based material can be used as the electrolyte 109. When using a solid electrolyte, it is not necessary to install a separator or spacer. In addition, when using a solid electrolyte or a gel-like electrolyte, the entire battery can be solidified or gelled, eliminating the risk of leakage and significantly improving safety.

[0167] For the exterior body 110, for example, a three-layer laminated film can be used, which is formed by providing a metal thin film with excellent flexibility, such as aluminum, stainless steel, copper, or nickel, on a film made of a material such as polyethylene, polypropylene, polycarbonate, ionomer, or polyamide, and further providing an insulating synthetic resin film such as a polyamide-based resin or a polyester-based resin on the metal thin film. At this time, the insulating synthetic resin film preferably covers the surface of the secondary battery 100. By adopting such a three-layer structure, the permeation of the electrolyte and gas is blocked, and the insulation property is Ensure and have electrolyte resistance at the same time.

[0168] With the above configuration, mass production is easy, and a small-sized power storage device that can be bent can be provided. In addition, the power storage device with the above configuration can be arranged along the curved shape of electronic devices such as wearable devices, or folded and arranged in a limited space Therefore, it can be mounted on various electronic devices such as wearable devices. Therefore, the power storage device with the above configuration can contribute to the spread of wearable devices and other electronic devices of various shapes, and economic development promoted by the spread of wearable devices and the like. It can be said that it can contribute to the economic development and the like promoted by the spread of wearable devices and the like. That is.

[0169] In addition, in this embodiment, one aspect of the present invention has been described. Or, in other embodiments one aspect of the present invention is described. However, one aspect of the present invention is not limited to these That is, in this embodiment and other embodiments, various aspects of the invention are described Therefore, 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 applying to a secondary battery or a lithium ion secondary battery is shown, but one aspect of the present invention is not limited to this. In some cases, or depending on the situation, one aspect of the present invention is various secondary batteries, lead-acid batteries, lithium ion polymer secondary batteries, nickel-hydrogen storage batteries nickel-cadmium storage batteries, nickel-iron storage batteries, nickel-zinc storage batteries, silver oxide-zinc storage batteries solid batteries, air batteries, zinc-air batteries, lithium-air batteries, primary batteries, capacitors or electric double layer capacitors, ultra-capacitors, super-capacitors, lithium ion capacitors, etc. may be applied. Or for example, in some cases, Alternatively, depending on the situation, one aspect of the present invention may or may not be applied to a secondary battery or a lithium-ion secondary battery. For example, as one aspect of the present invention, examples of application to a curved power storage device, a flexible power storage device, or a deformable power storage device are shown, but one aspect of the present invention is not limited thereto. In some cases or depending on the situation, one aspect of the present invention may be applied to power storage devices of various shapes or power storage devices having various hardnesses. Also, for example, in some cases or depending on the situation, one aspect of the present invention may be applied to a flat power storage device that is not curved or a cylindrical power storage device. Or, for example, in some cases or depending on the situation, one aspect of the present invention may be applied to a power storage device that has no flexibility and cannot be deformed. This embodiment can be implemented in appropriate combination with other embodiments. (Embodiment 2) In this embodiment, the manufacturing method of the secondary battery 100 described in Embodiment 1 will be described with reference to FIGS. 24 to 27. [1. Fabrication of Electrodes] First, a paste containing at least a negative electrode active material and a solvent is applied to one surface of the strip-shaped negative electrode current collector 105. At this time, as shown in FIG. 24(A), the paste is applied to the negative electrode current collector 105 with relatively wide intervals 242 and relatively narrow intervals 243 alternatingly provided. Then, the solvent contained in the paste is volatilized by heating to provide a negative electrode active material layer 106 on one surface of the negative electrode current collector 105.

[0170]

[0171]

[0172]

[0173] Further, a paste containing at least a positive electrode active material and a solvent is applied to one surface of the strip-shaped positive electrode current collector 101. At this time, as shown in FIG. 24(B), the paste is applied to the positive electrode current collector 101 with an interval 241 therebetween. Thereafter, the solvent contained in the paste is volatilized by heating, and a positive electrode active material layer 102 is provided on one surface of the positive electrode current collector 101.

[0174] [2. Production of laminate] A positive electrode 111, a separator 108, and a negative electrode 115 are stacked to produce a laminate 270. At this time, as shown in FIG. 24(C), a relatively wide interval 242 in the negative electrode current collector 105 that does not have the negative electrode active material layer 106 is sagged, and the positive electrode active material layer 102 and the negative electrode active material layer 106 may be stacked so as to face each other.

[0175] Note that the separator 108 may be formed in a bag shape and configured to wrap the positive electrode 111 with the separator 108. Thereby, it is possible to more reliably prevent the positive electrode 111 and the negative electrode 115 from coming into contact with each other and causing a short circuit.

[0176] For example, the positive electrode 111 can be sandwiched between the separator 108 folded in two, and the outer peripheral portion of the separator 108 can be joined to form a bag-shaped separator 108. The joining of the outer peripheral portion of the separator 108 may be performed using an adhesive or the like, or may be performed by ultrasonic welding or heating.

[0177] Note that the separator 108 is not limited to being bent. For example, it may be formed by sandwiching the positive electrode 111 between two separators. In that case, the joint portion may be formed in a shape surrounding most of the four sides.

[0178] Next, a laminate 270 including a positive electrode 111, a separator 108, and a negative electrode 115 is folded in a zigzag pattern. For the laminate 270, for example, at the position of the dotted line 244 shown in FIG. 24(D), it is valley-folded, and at the position of the dotted line 245, it is mountain-folded. As shown in FIG. 25(A), the positive electrode current collector 101, the negative electrode current collector 105, and the separator 108 can be folded in a zigzag pattern. At this time, the relatively wide interval 242 of the negative electrode current collector 105 that does not have the negative electrode active material layer becomes a sagging folded portion 272 by being folded.

[0179] In this way, by folding the strip-shaped positive electrode 111 and the strip-shaped negative electrode 115 in a stacked zigzag pattern, the laminate 270 can be miniaturized. It is difficult to fabricate a small laminate 270 by laminating small strip-shaped positive and negative electrodes, but with the present method of folding the strip-shaped positive electrode 111 and the strip-shaped negative electrode 115 in a stacked zigzag pattern, a small laminate 270 that meets the requirements can be easily formed.

[0180] [3. Attachment of Leads] As shown in FIGS. 25(A) and (B), near the end portion 271 of the negative electrode current collector 105 and the sagging folded portion 272 are overlapped, and ultrasonic waves are applied while applying pressure to connect them (ultrasonic welding) to form a welded portion 201. Further, as shown in FIG. 25(C), a negative electrode lead 145 having a sealing layer 1 40 is welded to the welded portion 201. The step of welding the negative electrode lead 145 to the welded portion 201 may be performed simultaneously with the formation of the welded portion 201.

[0181] Next, as shown in FIG. 25(C), the positive electrode tab of the positive electrode current collector 101 and the sealing layer 140 are provided. Apply ultrasonic waves while applying pressure to electrically connect the positive electrode lead 141 and the like.

[0182] The lead electrode is prone to cracking or breakage due to stress generated by externally applied force after the production of the secondary battery 100.

[0183] Therefore, when ultrasonic welding the positive electrode lead 141, sandwich it with a bonding die having protrusions so that a curved portion can be provided on the positive electrode tab. By providing this curved portion, the stress generated by externally applied force after the production of the secondary battery 100 can be relaxed. Therefore the reliability of the secondary battery 100 can be enhanced.

[0184] Also, it is not limited to forming a curved portion on the positive electrode tab. The material of the positive electrode current collector may be made of stainless steel with a certain strength, and the film thickness of the positive electrode current collector is set to 10 μm or less so that the stress generated by externally applied force after the production of the secondary battery can be easily relaxed. This may also be configured as a structure.

[0185] [4. Preparation of the exterior body] Fold the film used for the exterior body at the portion indicated by the dotted line (see Fig. 26(A)), and bond the overlapping side by thermocompression bonding. The portion where one side of the exterior body 110 is bonded by thermocompression bonding is shown as the bonding portion 110a in Fig. 26(B).

[0186] [5. Enclosure of the electrolyte] Cover the laminate 270 with the connected leads with the exterior body 110 (see Fig. 26(C)). Then, thermally weld one side of the exterior body 110 that overlaps with the sealing layer 140 of the positive electrode lead 141 and the sealing layer 140 of the negative electrode lead 145 (see Fig. 27(A)).

[0187] Next, from the unsealed side 110b of the exterior body 110 shown in Fig. 27(A), the electrolytic solution 1 09 is injected into the region surrounded by the exterior body 110. Then, evacuation, heating, and pressurization are performed while sealing the remaining side of the exterior body 110, whereby the secondary battery 100 can be manufactured (see Fig. 27(B)). These operations are carried out in an environment where oxygen and moisture are excluded, such as by using a glove box. The evacuation may be carried out using a degassing sealer or a liquid injection sealer, etc . Heating and pressurization can be achieved by sandwiching with two heatable bars provided by the sealer . Each condition can be, for example, a vacuum degree of 60 kPa, heating at 190 °C, and pressurization at 0.1 MPa for 3 seconds

[0188] [6. Modification Example] Here, modification examples of the above-described method for manufacturing an electrode, method for manufacturing a laminate, and attachment of a lead will be described .

[0189] First, a paste containing at least a negative electrode active material and a solvent is applied to one surface of the strip-shaped negative electrode current collector 105 . At this time, as shown in Fig. 28(A), the paste is applied to the negative electrode current collector 105 with an interval 241 . Then, the solvent contained in the paste is volatilized by heating, and a negative electrode active material layer 106 is provided on one surface of the negative electrode current collector 105, whereby the negative electrode 115 is manufactured .

[0190] In the same manner as the manufacture of the negative electrode 115, a paste containing at least a positive electrode active material and a solvent is applied to one surface of the strip-shaped positive electrode current collector 101 to manufacture the positive electrode 111 (see Fig. 28(B)) .

[0191] Next, the positive electrode 111, the separator 108, and the negative electrode 115 are stacked to manufacture the laminate 270 。At this time, as shown in FIG. 28(C), the positive electrode active material layer 102 and the negative electrode active material layer 106 are arranged to face each other.

[0192] Next, the laminate 270 including the positive electrode 111, the separator 108, and the negative electrode 115 is folded in a zigzag manner. With respect to the laminate 270, it is valley-folded at the position of the dotted line 244 shown in FIG. 28(D) and mountain-folded at the position of the dotted line 245, so that, as shown in FIG. 29(A), the positive electrode current collector 1 01, the negative electrode current collector 105, and the separator 108 can be folded together in a zigzag manner. This can be done.

[0193] Next, as shown in FIG. 29(B), the positive electrode tab of the positive electrode current collector 101 and the positive electrode lead 141 having the sealing layer 140 are electrically connected by applying ultrasonic waves while applying pressure.

[0194] In the same manner as the positive electrode lead 141, the negative electrode lead 145 having the sealing layer 140 is connected to the negative electrode tab of the negative electrode current collector 105.

[0195] Even in the case of this modification, a laminate 270 having the positive electrode lead 141 and the negative electrode lead 145 may be manufactured.

[0196] This embodiment can be implemented in appropriate combination with other embodiments.

[0197] (Embodiment 3) In this embodiment, the structure and manufacturing method of the exterior body 110 applicable to the power storage device according to one aspect of the present invention will be described with reference to FIGS. 30 to 34.

[0198] FIG. 30(A) shows a front view of the secondary battery 100A having the exterior body 110. Further, FIG. 30 (B) and (C) show diagrams for explaining an example of a method for manufacturing the secondary battery 100A. Also, FIG. 30(D) shows a developed view of the exterior body 110.

[0199] First, the exterior body 110 has a rectangular shape with sides 301, 302, 303, and 304, and by bending at the bending portion 308, sides 303 and 304 are overlapped. Also, the bending portion 308 includes sides 301 and 302, and side 301 is overlapped with side 301. Also, side 302 is overlapped with side 302 (see FIG. 30(A)).

[0200] A laminate 270 having a positive electrode 111, a separator 108, and a negative electrode 115 is disposed at a position surrounded by the exterior body 110 having the bending portion 308. At this time, the positive electrode lead 141 connected to the positive electrode 111 and the negative electrode lead 145 connected to the negative electrode 115 are disposed such that the laminate 270 overlaps with side 301 of the exterior body 110 (see FIG. 30(B)). Next, the outer peripheral portion of the exterior body 110 other than the inlet 306 for injecting the electrolyte 109 is joined by thermocompression bonding (see FIG. 30(C)). Note that the portion joined by thermocompression bonding is shown as the joint portion 110a.

[0201] Then, the electrolyte 109 is introduced from the inlet 306 into the position surrounded by the exterior body 110 under a reduced pressure atmosphere or an inert gas atmosphere. Finally, the inlet 306 is joined by thermocompression bonding. In this way, the secondary battery 100A can be manufactured (see FIG. 30(A)).

[0202] When the secondary battery 100A is formed in an elongated shape, it is preferable to use the exterior body 110 of this configuration because the secondary battery 100 can be miniaturized. More specifically, an exterior body 11 having a rectangular shape ​​​​​​​​When the length of side 301 of 0 is W and the lengths of sides 303 and 304 are L, if L ≥ W, it is preferable to adopt the configuration of the exterior body 110 of the secondary battery 100A shown in Fig. 30(A). By doing so, the proportion occupied by the joint portion 110a in the secondary battery 100A can be reduced. Therefore, the secondary battery 100A can be miniaturized.

[0203] Also, when the size of the secondary battery is specified, by adopting the configuration of the secondary battery 100A, the capacity of the secondary battery 100A can be increased, which is preferable. More specifically, when the secondary battery 100A is manufactured using an exterior body 110 where L ≥ W, the proportion occupied by the joint portion 110a in the secondary battery 100A can be reduced. As a result, the positive electrode 111 and the negative electrode 115 of the secondary battery 100A can be enlarged, and the capacity of the secondary battery 100A can be increased.

[0204] Figs. 33(A) and (B) show the external views of the secondary battery 100A.

[0205] As shown in Fig. 33(B), the secondary battery 100A may be further miniaturized by bending the joint portion 110a of the exterior body 110.

[0206] Hereinafter, other examples of the exterior body 110 will be described.

[0207] Fig. 31(A) shows the front view of the secondary battery 100B having the exterior body 110. Figs. 31(B) and (C) show diagrams for explaining an example of the manufacturing method of the secondary battery 100B. Similar to the exterior body 110 of the secondary battery 100A, the exterior body 110 of the secondary battery 100B has a rectangular shape with sides 301, side 302, side 303, and side 304, and has a bent portion 30 By folding at 8, side 303 and side 304 are overlapped. Also, the folding part 30 8 includes side 301 and side 302. Side 301 is overlapped with side 301. Also, side 30 2 is overlapped with side 302.

[0208] A laminate 270 having a positive electrode 111, a separator 108 , and a negative electrode 115 is disposed at a position surrounded by the exterior body 110 having the folding part 308. At this time, the positive electrode lead 141 is disposed so as to overlap with side 301 of the exterior body 110, and the negative electrode lead 145 is disposed so as to overlap with side 302.

[0209] Thereafter, a secondary battery 100B can be manufactured in the same manner as the manufacturing method of the secondary battery 100A.

[0210] FIG. 32(A) shows a front view of a secondary battery 100C having an exterior body 110. FIGS. 32(B) , (C) show diagrams for explaining an example of the manufacturing method of the secondary battery 100C. The secondary battery 100C has a cylindrical exterior body 110 having two openings.

[0211] After disposing the positive electrode 111, the separator 108, and the negative electrode 115 inside the cylindrical exterior body 110, a lead-in port 306 for injecting the electrolytic solution 109 is left at a part of one opening, and the openings of the cylindrical exterior body 110 are joined by thermocompression bonding (see FIG. 32(C)).

[0212] Thereafter, the secondary battery 100C can be manufactured in the same manner as the secondary battery 100A or the secondary battery 100B.

[0213] When the secondary battery 100 is in an elongated shape, the secondary battery 100A, the secondary battery 100B, and When the exterior body 110 of the secondary battery 100C is used, it is possible to increase the capacity per unit volume of the secondary battery 100, which is preferable. The capacity can be increased, which is preferable.

[0214] Also, in the secondary battery 100 having the zigzag positive current collector 101 or the negative current collector 105 described in Embodiment 1 and Embodiment 2, when the exterior body 110 of the secondary battery 100A, the secondary battery 100B, or the secondary battery 100C is used, it can be made into a secondary battery that is more easily curved, smaller in size, and has a large capacity, which is more preferable. The positive current collector 101 and the negative current collector 105 do not necessarily have a bent portion.

[0215] The positive current collector 101 and the negative current collector 105 may each be, for example, strip-shaped or flat-plate-shaped. Also, the strip-shaped positive electrode 111, the strip-shaped negative electrode 115, and the separator 108 may be wound.

[0216] As an example of the secondary battery 100 having the strip-shaped positive current collector 101 and the strip-shaped negative current collector 105, a cross-sectional view taken along the dashed line A1 - A2 of the secondary battery 100 shown in FIG. 33(A) is shown in FIG. 34(A), and a cross-sectional view taken along the dashed line B1 - B2 is shown in FIG. 34(B).

[0217] The secondary battery 100A includes a flat-plate-shaped positive electrode 111, a flat-plate-shaped negative electrode 115, a separator 108, an electrolytic solution 109, an exterior body 110, a positive electrode lead 141, and a negative electrode lead 145. A separator 108 is installed between the positive electrode 111 and the negative electrode 115 disposed at a position surrounded by the exterior body 110. Also, an electrolytic solution 109 is poured into a position surrounded by the exterior body 110. The positive electrode 111 has a positive current collector 101 and a positive electrode active material layer 102. The negative The electrode 115 has a negative electrode current collector 105 and a negative electrode active material layer 106 .

[0218] In the secondary battery according to one embodiment of the present invention, the lead electrodes can be freely arranged, so that the design is free. Therefore, the degree of freedom in designing a product using the secondary battery of one embodiment of the present invention can be increased. Furthermore, the productivity of products using the secondary battery of one embodiment of the present invention can be improved.

[0219] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0220] (Embodiment 4) In this embodiment, a power storage device according to one embodiment of the present invention will be described with reference to FIG. The following describes an electronic device that can store electricity. A secondary battery 100 is used as an example of the electricity storage device. Reveal.

[0221] The secondary battery 100 according to one embodiment of the present invention is suitable for use in wearable devices because of its flexibility. It is appropriate.

[0222] For example, it can be mounted on a glasses-type device 400 as shown in FIG. The device 400 includes a frame 400a and a display unit 400b. By installing the secondary battery 100 in the temple of the 400a, the weight balance is good and it can be used continuously. The glasses-type device 400 can be used for a long time.

[0223] The present invention can also be implemented in a headset type device 401. 401 includes at least a microphone part 401a, a flexible pipe 401b, and an earphone. The flexible pipe 401b and the earphone section 401c include multiple A number of secondary batteries 100 can be provided.

[0224] Further, it can be mounted on a device 402 that can be directly attached to the body. Inside a thin housing 402a having flexibility of the device 40 2, a plurality of secondary batteries 100 can be provided.

[0225] Further, it can be mounted on a device 403 that can be attached to clothing. Inside a thin housing 403a having flexibility of the device 403, a plurality of secondary batteries 100 can be provided.

[0226] Further, it can be mounted on a bracelet-type device 404. The bracelet-type device 404 has a display portion 404b on a housing 40 4a, and a plurality of secondary batteries 1 00 can be provided inside the housing 404a having a curved portion.

[0227] Further, it can be mounted on a wristwatch-type device 405. The wristwatch-type device 405 has a display portion 405a, and a plurality of secondary batteries 100 can be provided.

[0228] Further, since the secondary battery 100 according to one aspect of the present invention can be bent, it can be mounted with high space efficiency in various electronic devices. For example, the stove 410 shown in Fig. 35(B) has a module 411 attached to a main body 412, and the module 411 includes a secondary battery 100 , a motor, a fan, an air outlet 411a, and a thermoelectric power generation device. In the stove 410, after fuel is introduced and ignited from an opening 412a, the motor and the fan of the module 4 11 are rotated using the power of the secondary battery 100, and outside air can be sent from the air outlet 411a into the inside of the stove 410. Since outside air can be efficiently taken in in this way, it becomes a stove with strong firepower. ​​​​​This is possible. Furthermore, using the thermal energy obtained from the combustion of fuel, cooking can be performed on the upper grill 41 in 3. Also, this thermal energy can be converted into electricity by the thermoelectric power generation device of the module 411 and used to charge the secondary battery 100. Furthermore, the electric power charged in the secondary battery 100 can be output from the external terminal 411b.

[0229] This embodiment can be implemented in appropriate combination with other embodiments.

[0230] (Embodiment 5) Furthermore, an example of a moving body, which is an example of an electronic device, will be described with reference to FIG. 36.

[0231] The secondary battery described in the previous embodiment can be used as a battery for control. The control battery can be charged by external power supply by plug-in technology or non-contact power supply. When the moving body is an electric railway vehicle, it can be charged by power supply from an overhead wire or a conductive rail.

[0232] FIGS. 36(A) and (B) show an example of an electric vehicle. In the electric vehicle 760, a battery 761 is mounted. The power of the battery 761 is adjusted by the control circuit 762 and supplied to the drive device 763. The control circuit 762 is controlled by a processing device 764 having a ROM, RAM, CPU, etc. (not shown). M, CPU, etc.

[0233] The drive device 763 is configured by combining a DC motor or an AC motor alone, or a motor and an internal combustion engine. The processing device 764 receives the operation information (acceleration of the driver of the electric vehicle 760, deceleration, stop, etc.) and the information during traveling (information such as uphill and downhill, load information applied to the drive wheels Based on input information (such as), a control signal is output to the control circuit 762. The control circuit 762 adjusts the electrical energy supplied from the battery 761 according to the control signal of the processing device 764 to control the output of the drive device 763. When an AC motor is installed, although not shown in the figure, an inverter for converting DC to AC is also built in.

[0234] The battery 761 can be charged by external power supply using plug-in technology . For example, the battery 761 is charged from a commercial power supply through a power plug. The charging is performed by converting it to a DC constant voltage having a certain voltage value through a conversion device such as an AC / DC converter. By mounting a secondary battery using the electrode for a secondary battery according to an aspect of the present invention as the battery 761, it is possible to contribute to increasing the capacity of the battery and the like, and improving convenience. In addition, by improving the characteristics of the battery 761, if the battery 761 itself can be made smaller and lighter, it contributes to reducing the weight of the vehicle, and thus the fuel efficiency can be improved.

[0235] Needless to say, if the secondary battery according to an aspect of the present invention is provided, it is not particularly limited to the electrical equipment shown above.

[0236] This embodiment can be implemented in appropriate combination with other embodiments.

[0237] (Embodiment 6) In this embodiment, a wireless sensor equipped with a power storage device will be described with reference to FIGS. 37 and 38. As an example of the power storage device, a secondary battery 100 is cited.

[0238] [Configuration Example 1 of Wireless Sensor] Figures 37(A) and 37(B) are external views showing a configuration example of the wireless sensor 800. The wireless sensor 800 includes a circuit board 801, a battery 802, and a sensor 803. A label 804 is attached to the battery 802. Further, as shown in FIG. 37(B), the wireless sensor 800 includes a terminal 806, a terminal 807, an antenna 808, and an antenna 80 9. As the battery 802, a secondary battery 100 can be used.

[0239] The circuit board 801 includes a terminal 805 and an integrated circuit 810. The terminal 805 is connected to the sensor 803 via a conducting wire 8 13. Note that the number of terminals 805 is not limited to two, and any necessary number can be provided.

[0240] Also, the circuit board 801 may be formed with semiconductor elements such as transistors and diodes, resistance elements, or wiring.

[0241] If the heat generated by the battery 802 or the electromagnetic field generated by the antennas 808 and 809 affects the operation of the sensor 803, the distance of the conducting wire 813 can be increased to separate the sensor 803 from the battery 802 or the antennas 808 and 809. For example, the length of the conducting wire 813 may be 1 cm or more and 1 m or less, preferably 1 cm or more and 50 cm or less, and more preferably 1 cm or more and 30 cm or less.

[0242] Also, the sensor 803 may be disposed on the circuit board 801.

[0243] The integrated circuit 810 may be provided on the surface of the circuit board 801 in contact with the battery 802. .

[0244] Antenna 808 and antenna 809 are not limited to a coil shape, and may be, for example, linear or plate-shaped. Further, antennas such as a planar antenna, an aperture antenna, a traveling wave antenna, an EH antenna, a magnetic field antenna, and a dielectric antenna may be used. Alternatively, antenna 808 or antenna 809 may be a flat conductor. This flat conductor can function as one of the conductors for electric field coupling. That is, antenna 808 or antenna 809 may function as one of the two conductors of the capacitor. As a result, power can be exchanged not only by an electromagnetic field and a magnetic field but also by an electric field. That is, antenna 808 or antenna 809 may function as one of the two conductors of the capacitor. As a result, power can be exchanged not only by an electromagnetic field and a magnetic field but also by an electric field. Thereby, power can be exchanged not only by an electromagnetic field and a magnetic field but also by an electric field. Thereby, power can be exchanged not only by an electromagnetic field and a magnetic field but also by an electric field.

[0245] Integrated circuit 810 has a circuit composed of Si transistors or transistors using oxide semiconductors (OS transistors). Integrated circuit 810 has a circuit composed of Si transistors or transistors using oxide semiconductors (OS transistors).

[0246] The line width of antenna 808 is preferably larger than the line width of antenna 809. Thereby, the amount of power received by antenna 808 can be increased. Thereby, the amount of power received by antenna 808 can be increased.

[0247] Sensor 803 is a circuit having a function of outputting various information such as thermal, mechanical, or electromagnetic information as analog data. Sensor 803 is a circuit having a function of outputting various information such as thermal, mechanical, or electromagnetic information as analog data.

[0248] Wireless sensor 800 has a layer 812 between antenna 808 and antenna 809 and battery 802. Layer 812 has a function of shielding, for example, the electromagnetic field by battery 802. As layer 812, for example, a magnetic material can be used. Wireless sensor 800 has a layer 812 between antenna 808 and antenna 809 and battery 802. Layer 812 has a function of shielding, for example, the electromagnetic field by battery 802. As layer 812, for example, a magnetic material can be used. Wireless sensor 800 has a layer 812 between antenna 808 and antenna 809 and battery 802. Layer 812 has a function of shielding, for example, the electromagnetic field by battery 802. As layer 812, for example, a magnetic material can be used.

[0249] [Configuration Example 2 of Wireless Sensor] FIG. 38 is an external view showing a configuration example of wireless sensor 880. Wireless sensor 880 is a support 850, an antenna 851, an integrated circuit 852, a circuit board 853, a sensor 855, and a battery 854. As the battery 854, a secondary battery 100 can be used.

[0250] The integrated circuit 852 is arranged on the circuit board 853. Also, the circuit board 853 may be formed with semiconductor elements such as transistors and diodes, resistor elements or wirings.

[0251] The integrated circuit 852 has a circuit composed of Si transistors or OS transistors.

[0252] The antenna 851 is connected to the integrated circuit 852 via a conducting wire 860. For details of the antenna 851, refer to the description of the antenna 808 or the antenna 809 of the wireless sensor 800.

[0253] The sensor 855 is connected to the integrated circuit 852 via a conducting wire 856. Also, the sensor 855 may be formed outside the support 850 or on the support 850.

[0254] The sensor 855 is a circuit having a function of outputting various information such as thermal, mechanical, or electromagnetic information as analog data.

[0255] The battery 854 has a terminal 858 having a function as one of the positive electrode and the negative electrode, and a terminal 859 having a function as the other of the positive electrode and the negative electrode. Each terminal is connected to the integrated circuit 852 via a conducting wire 857 and the circuit board 853.

[0256] As the support 850, for example, glass, quartz, plastic, metal, stainless steel​​​​​​​ · Foil, tungsten foil, flexible substrate, laminated film, substrate film, paper containing fibrous materials, or wood can be used. As an example of the flexible substrate, there are plastics typified by polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), or flexible synthetic resins such as acrylic. As an example of the laminated film, there are polypropylene, polyester, polyvinyl fluoride, or polyvinyl chloride. As an example of the base film, there are polyester, polyamide, polyimide, aramid, epoxy, inorganic vapor deposition film, or papers. The wireless sensor 800 is preferably thin. In particular, the thickness including the battery 854 and the support 850 is preferably 0.1 mm or more and 5 mm or less, more preferably 0.1 mm or more and 3 mm or less, and even more preferably 0.1 mm or more and 1 mm or less. By configuring the wireless sensor 800 as described above, it becomes possible to embed the wireless sensor 800 in papers such as posters and cardboard. Also, the wireless sensor 800 preferably has flexibility. In particular, the support 850 and the battery 854 preferably can be deformed within a range of a curvature radius of 30 mm or less, preferably 10 mm or less. By configuring the wireless sensor 800 as described above, it becomes possible to follow the movement of clothes or the human body when attaching the wireless sensor 800 to clothes or the human body. To satisfy the above configuration, the battery 854 is preferably thin and flexible.

[0257]

[0258]

[0259] ​​​​​​​​​​​​​The exterior body of the battery 854 is formed, for example, in the order of a first thin film, a second thin film, and a third thin film. The third thin film is used as the outer surface of the exterior body. The first thin film is made of polyethylene, polypropylene, polycarbonate, etc. Materials such as ionomer, polyamide, etc. may be used for the second thin film. A thin metal film having excellent flexibility, such as aluminum, stainless steel, copper, or nickel, may be used. As the insulating layer, a synthetic resin film such as a polyamide resin or a polyester resin may be used. .

[0260] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0261] (Embodiment 7) In this embodiment, an application example of the wireless sensor described in the sixth embodiment will be described with reference to FIGS. 39 to 41 will be described with reference to the wireless sensor 900 shown in FIG. It is possible to apply the wireless sensor 800 or the wireless sensor 880 described above.

[0262] For example, as shown in FIG. 39, a wireless sensor 900 is attached to an item 921 or installed inside the item. Then, a wireless signal 911 is transmitted from an external reader 922. The wireless sensor 900 obtains information such as temperature without touching the item 921. and can be transmitted to the reader 922.

[0263] Another application of the wireless sensor can be explained by the schematic diagram shown in FIG. For example, a wireless sensor 900 can be embedded in the tunnel wall, and a wireless signal 911 can be received from the outside. The wireless sensor 900 that receives the wireless signal 911 detects the tunnel wall by the sensor. It is possible to acquire and transmit the information of

[0264] As another application form of the wireless sensor, it can be described with the schematic diagram shown in Fig. 40(B). For example, a wireless sensor 900 is embedded in the wall surface of the support column of a bridge, and a wireless signal 91 1 is transmitted from the outside. The wireless sensor 900 that has received the wireless signal 911 can acquire and transmit the information inside the support column of the bridge by the sensor.

[0265] As another application form of the wireless sensor, it can be described with the schematic diagram shown in Fig. 41. For example, the wireless sensor 900 is attached to the human body using an adhesive pad or the like, and a wireless signal 911 is transmitted from the reader 922. The wireless sensor 900 that has received the wireless signal 911 gives a signal to the electrode 931 or the like attached to the human body via the wiring 932 to acquire information such as biological information, and can transmit it. The acquired information can be confirmed on the display unit 933 of the reader 922.

[0266] This embodiment can be implemented in appropriate combination with other embodiments.

Example

[0267] In this example, the result of estimating the capacity of the secondary battery 100A shown in Embodiment 3 will be described. As shown in Fig. 42(A), as an example, a secondary battery 351 having an exterior body with the same shape as the secondary battery 100A is shown, and in Fig. 42(B), as a comparative example, a secondary battery 352 having an exterior body with a different shape from the secondary battery 100A is shown.

[0268] As shown in Fig. 42(A), the secondary battery 351 has eight sheets of - A plate-shaped positive electrode 111, eight sheet-shaped negative electrodes 115, a separator 108, and an electrolytic solution It has. The positive electrode 111 is electrically connected to the positive electrode lead 141, and the negative electrode 115 is the negative electrode - It is electrically connected to the lead 145. Further, the electrode 361 has a current collector 365 and a current collector 3 65 and an active material layer 366 provided thereon.

[0269] The exterior body 110 of the secondary battery 351 will be described. The height (length in the y-axis direction of the exterior body 110) is L c The width (length in the x-axis direction) of the exterior body 110 is W c The width of the joint 1 10a of the exterior body 110 is R, and the distance in the x-axis direction between the joint 110a and the positive electrode 111 or the negative electrode 115 And the distance in the x-axis direction between the bent portion 308 and the positive electrode 111 or the negative electrode 115 are both Denoted as S. Also, in the electrode 361, the height of the active material layer 366 is L e The width of the active material layer 366 Is W e However, in the portion sandwiching the positive electrode lead 141 and the negative electrode lead 145 The width (length in the y-axis direction) of the joint 110a is set to R + 1 (mm).

[0270] The height L of the exterior body 110 c = 30 mm, the width of the exterior body 110 is W c = 15 mm is fixed, and Example 1, Example 2, and Example 3 are assumed in which the width R And the distance S are respectively changed, and the height L And width W of these e Of the active material layer 366 e Were calculated.

[0271] In addition, the distance in the y-axis direction between the joint 110a in the portion without the positive electrode lead 141 and the negative electrode lead 145 and the positive electrode 111 or the negative electrode 115 was fixed at 1 mm.

[0272] Furthermore, the height L of the estimated active material layer 366 e and the width W e are used to calculate the area A of the active material layer 366, and based on the area A of the active material layer 366, the capacities C of Example 1, Example 2, and Example 3 are estimated. Note that the capacity C is calculated assuming that the capacity of a secondary battery obtained using a positive electrode having a positive electrode active material layer with an area of 1 cm 2 and a negative electrode having a negative electrode active material layer with an area of 1 cm 2 is 3.5 mA h.

[0273] As shown in FIG. 42(B), the position of the bent portion of the exterior body of the secondary battery 352 is different from that of the secondary battery 351.

[0274] As a comparative example, the exterior body of the secondary battery 352 will be described. The height ( length in the y-axis direction) of the exterior body 110 is L c , the width (length in the x-axis direction) of the exterior body 110 is W c , the width of the joint portion 110a of the exterior body 110 is R, and the distance in the x-axis direction between the joint portion 110a and the positive electrode 111 or the negative electrode 115 is S. Also, in the electrode 361, the height of the active material layer 366 is L , and the width of the active material layer 366 is W e . However, in the portion sandwiching the positive electrode lead 141 and the negative electrode lead 145, the width (length in the y-axis direction) of the joint portion 110a is R + 1 (mm). e Furthermore, assuming Comparative Example 1, Comparative Example 2, and Comparative Example 3 in which the height L of the exterior body 110 is fixed at L = 30 mm, the width W of the exterior body 110 is fixed at W = 15 mm

[0275] and the width R and the distance S are each changed, the height L c and the width W c of the active material layer 366 in each example are calculated. Furthermore, the estimated e and width W e ​​​​ The height L of the active material layer 366 e and the width W e are used to calculate the area A of the active material layer 366, and the capacities C of Comparative Example 1, Comparative Example 2, and Comparative Example 3 are estimated from the area A of the active material layer 366.

[0276] Note that the distance in the y-axis direction between the bent portion 308 and the positive electrode 111 or the negative electrode 115 was fixed at 1 m. m.

[0277] In Example 1 and Comparative Example 1, assuming an exterior body with a width R of 2 mm and a distance S of 1 mm, the capacity C was estimated. Also, in Example 2 and Comparative Example 2, assuming an exterior body with a width R of 1 mm and a distance S of 1.5 mm, the capacity C was estimated. Further, in Example 3 and Comparative Example 3, assuming an exterior body with a width R of 1 mm and a distance S of 1 mm, the capacity C was estimated. The obtained results are shown in Table 1.

[0278]

Table 1

[0279] As shown in Table 1, when comparing conditions with the same values of the width R and the distance S, it was found that the sample to which one aspect of the present invention was applied had a larger capacity C of the secondary battery than the comparative examples.

[0280] Also, when comparing Example 1 and Example 3, it was found that the smaller the width R, the larger the capacity C of the secondary battery could be. Further, when comparing Example 2 and Example 3, it was found that the smaller the distance S, the larger the capacity C of the secondary battery could be.

[0281] From the results of this example, in the secondary battery 351 to which the configuration of the secondary battery 100A was applied, the secondary battery ​Compared with 352, it was found that the area of the joint portion 110a can be narrowed, and the capacity of the secondary battery can be increased.

Explanation of Signs

[0282] 100 Secondary battery 100A Secondary battery 100B Secondary battery 100C Secondary battery 101 Positive current collector 102 Positive electrode active material layer 105 Negative current collector 106 Negative electrode active material layer 107 Friction layer 108 Separator 108a Separator 108b Separator 109 Electrolyte 109a Gel electrolyte 110 Outer package 110a Joint portion 110b Side 111 Positive electrode 111a Positive electrode 111b Positive electrode 115 Negative electrode 115a Portion 115b Portion 115c Portion 140 Sealing layer 141 Positive electrode lead 145 Negative electrode lead 201 Weld portion 201a Weld portion 202 Portion 211 Bending portion 211a Weld portion 212 Bending portion 213 Edge 221 First surface 222 Second surface 223 Third surface 224 Fourth surface 231 First region 232 Second region 241 Spacing ​242 interval 243 interval 244 dotted line 245 dotted line 250 dotted line 251 bending part 251a welding part 252 bending part 252a welding part 261 welding part 270 laminate 271 end 272 bending part 281 side 282 side 283 side 284 side 291 double arrow 293 double arrow 301 side 302 side 303 side 304 side 306 inlet 308 bending part 351 secondary battery 352 secondary battery 361 electrode 365 current collector 366 active material layer 400 glasses-type device 400a frame 400b display part 401 headset-type device 401a microphone part 401b flexible pipe 401c earphone part 402 device 402a housing 403 device 403a housing 404 armband-type device 404a housing 404b display part 405 wristwatch-type device 405a display part 410 stove 411 module 411a Air outlet 411b External terminal 412 Main body 412a Opening 413 Grill 760 Electric vehicle 761 Battery 762 Control circuit 763 Driving device 764 Processing device 800 Wireless sensor 801 Circuit board 802 Battery 803 Sensor 804 Label 805 Terminal 806 Terminal 807 Terminal 808 Antenna 809 Antenna 810 Integrated circuit 812 Layer 813 Conductive wire 850 Support 851 Antenna 852 Integrated circuit 853 Circuit board 854 Battery 855 Sensor 856 Conductive wire 857 Conductive wire 858 Terminal 859 Terminal 860 Conductive wire 880 Wireless sensor 900 Wireless sensor 911 Wireless signal 921 Article 922 Reader 931 Electrode 932 Wiring 933 Display unit

Claims

[Claim 1] A first electrode, a second electrode, and an electrolyte solution, The first electrode functions as either a positive electrode or a negative electrode, The second electrode functions as the other of the positive electrode and the negative electrode, the first electrode and the second electrode have an overlapping region; the first electrode has a first current collector and a first active material layer; the first current collector has a first surface and a second surface; the first active material layer is provided on the first surface, the first current collector has a first folded portion with the second surface facing inward, the second surface has a first region and a second region; the first region has an area overlapping with the second region, The power storage device, wherein the first region has a region that is connected to the second region at a location different from the first bent portion.

Images