Battery module and electronic device

Abstract

Provided is a flexible battery module. The battery module includes a flexible substrate part and a battery part. The flexible substrate part includes a metal layer that functions as electrical wiring. The battery part has: an exterior body; and electrodes (positive electrode and negative electrode) and connection terminals (positive electrode terminal and negative electrode terminal), which are provided in a space surrounded by the exterior body. Inside the battery part, the electrodes are connected to the connection terminals, and in addition, the connection terminals and the metal layer included in the flexible substrate are connected in an opening in the exterior body provided at a position overlapping the flexible substrate.

Description

Battery module and electronic device

[0001] The invention disclosed in this specification (hereinafter, sometimes referred to as "the present invention" in this specification) relates to an electricity storage device, a secondary battery, etc., and in particular to a lithium ion battery.

[0002] Alternatively, the present invention relates to an object, a method, or a manufacturing method, or to a process, a machine, a manufacture, or a composition of matter, or to a semiconductor device, a display device, a light-emitting device, a power storage device, a lighting device, an electronic device, a vehicle, or a manufacturing method thereof.

[0003] In recent years, various types of power storage devices have been actively developed, such as lithium-ion batteries, lithium-ion capacitors, and air batteries. In particular, demand for high-power, high-energy-density lithium-ion batteries has rapidly expanded in conjunction with the development of the semiconductor industry, and they are now indispensable in the modern information society as a rechargeable energy source, as they are used in portable information terminals such as mobile phones, smartphones, and notebook computers, portable music players, digital cameras, medical devices, and electrically powered vehicles such as hybrid vehicles (HVs), electric vehicles (EVs), and plug-in hybrid vehicles (PHVs).

[0004] Bendable electronic devices have been proposed for use in electronic devices such as mobile information terminals (Patent Document 1). Bendable batteries (which can also be called flexible batteries) have also been proposed for incorporation into bendable electronic devices (Patent Documents 2, 3, and 4).

[0005] 2. Description of the Related Art In electronic devices such as portable information terminals, the housings are becoming smaller and thinner, and it is therefore desirable for the volume occupied by the battery to be small and for the battery to have a large capacity.

[0006] Batteries may generate heat due to an internal short circuit or overcharging, and it is known that the heat generated can cause thermal runaway, leading to smoke, fire, or explosion.

[0007] Conventionally, to ensure the safety of batteries, a battery control circuit (sometimes referred to as a protection circuit) that prevents overcharging or overdischarging is mounted on a protection circuit board. Furthermore, IC (Integrated Circuit) chips, such as a CPU (Central Processing Unit) and memory, necessary for operating electronic devices are mounted on the control circuit board. The protection circuit board and the control circuit board are often rigid boards (hard printed circuit boards), fabricated separately, and connected via connectors or the like. The connection between the protection circuit board or the control circuit board and the battery is generally made using connection terminals (also referred to as leads or lead terminals) protruding from the end of the battery's exterior body.

[0008] U.S. Patent Application Publication No. 2015 / 0062840, Japanese Patent Application Publication No. 2016-027532, Japanese Patent Application Publication No. 2016-136508, and Japanese Patent Application Publication No. 2017-117776

[0009] An object of one embodiment of the present invention is to realize a battery module structure that is bendable, includes a circuit for safely controlling a battery, and can accommodate space saving due to miniaturization of a housing.

[0010] Another object of one embodiment of the present invention is to realize a configuration of an electronic device that can be bent, includes a circuit for safely controlling a battery, and can accommodate space saving due to miniaturization of the housing.

[0011] Another object of one embodiment of the present invention is to provide a control circuit board with a novel structure. Specifically, an object of one embodiment of the present invention is to provide a control circuit board with a novel flexible structure. Another object of one embodiment of the present invention is to provide a novel control circuit board or an electronic device including the novel control circuit board.

[0012] Another object of one embodiment of the present invention is to provide a battery with a novel structure. Specifically, an object of one embodiment of the present invention is to provide a battery with a novel flexible structure. Another object of one embodiment of the present invention is to provide a novel power storage device or an electronic device equipped with the novel battery.

[0013] Note that the description of these problems does not preclude the existence of other problems. One embodiment of the present invention does not necessarily have to solve all of these problems. Problems other than these can be extracted from the description in the specification, drawings, and claims.

[0014] One embodiment of the present invention is a battery module including a flexible substrate and a battery provided on the flexible substrate, the flexible substrate having a metal layer, the battery having an outer casing and an electrode and a connection terminal provided in a space surrounded by the outer casing, the electrode being connected to the connection terminal, and the connection terminal being connected to the metal layer in an opening provided in the outer casing at a position overlapping the flexible substrate.

[0015] In the above, the flexible substrate may have a first resin layer and a second resin layer, and the metal layer may be located between the first resin layer and the second resin layer.

[0016] In the above, it is preferable that the connection terminal has a resin layer, the resin layer being provided around the opening and being bonded to the exterior body.

[0017] Alternatively, one embodiment of the present invention includes a flexible substrate, an exterior body connected to the flexible substrate, and a positive electrode and a positive electrode terminal provided in a space surrounded by the exterior body, wherein the flexible substrate includes a first resin layer, a second resin layer, and a first metal layer positioned between the first resin layer and the second resin layer, the exterior body includes a third resin layer, a fourth resin layer, and a second metal layer positioned between the third resin layer and the fourth resin layer, the positive electrode includes a positive electrode current collector, and the positive electrode terminal includes a fifth resin layer and the third metal layer. one surface of the third metal layer is connected to the positive electrode current collector, the second resin layer has a region connected to the third resin layer, the other surface of the third metal layer has a region connected to the fourth resin layer via the fifth resin layer, the fifth resin layer, the fourth resin layer, the second metal layer, the third resin layer and the second resin layer have a first opening that extends from the first metal layer to the third metal layer, and the first metal layer and the third metal layer are connected in the first opening by a first conductive resin.

[0018] Alternatively, one aspect of the present invention is a semiconductor device including a flexible substrate, an exterior body connected to the flexible substrate, and a positive electrode, a negative electrode, a positive electrode terminal, and a negative electrode terminal provided in a space surrounded by the exterior body, wherein the flexible substrate includes a first resin layer, a second resin layer, a third resin layer, a first metal layer positioned between the first resin layer and the second resin layer, and a second metal layer positioned between the second resin layer and the third resin layer, and the exterior body includes a fourth the positive electrode has a positive electrode current collector, the negative electrode has a negative electrode current collector, the positive electrode terminal has a sixth resin layer and a fourth metal layer, the negative electrode terminal has a seventh resin layer and a fifth metal layer, one surface of the fourth metal layer is connected to the positive electrode current collector, one surface of the fifth metal layer is connected to the negative electrode current collector, the sixth resin layer, the fifth resin layer, the third metal layer, the fourth resin layer, and the third resin layer have a first opening extending from the second metal layer to the fourth metal layer, and the second metal layer and the fourth metal layer are connected in the first opening by a first conductive resin; the fifth resin layer, the sixth resin layer, the fifth resin layer, the third metal layer, the fourth resin layer, and the third resin layer have a first opening extending from the second metal layer to the fourth metal layer, and the second metal layer and the fourth metal layer are connected in the first opening by a first conductive resin; the fifth resin layer, the seventh resin layer, the fifth resin layer, the third metal layer, the fourth resin layer, the third resin layer, the second metal layer, and the second resin layer have a second opening extending from the first metal layer to the fifth metal layer, and the first metal layer and the fifth metal layer are connected in the second opening by a second conductive resin.

[0019] Another embodiment of the present invention is an electronic device in which a control circuit unit is provided over the battery module, and a display unit is provided over the control circuit unit.

[0020] According to one embodiment of the present invention, it is possible to realize a battery module configuration that is bendable, includes a circuit for safely controlling a battery, and can accommodate space saving due to a smaller housing.

[0021] According to one embodiment of the present invention, it is possible to realize a structure of an electronic device that can be bent, includes a circuit for safely controlling a battery, and can accommodate space saving due to miniaturization of the housing.

[0022] According to one embodiment of the present invention, a control circuit board having a novel structure can be provided. Specifically, a control circuit board having a novel flexible structure can be provided. According to one embodiment of the present invention, a novel control circuit board and an electronic device including the novel control circuit board can be provided.

[0023] According to one embodiment of the present invention, a battery with a novel structure can be provided. Specifically, a battery with a novel flexible structure can be provided. Alternatively, according to one embodiment of the present invention, a novel power storage device or an electronic device including the novel battery can be provided.

[0024] Note that the description of these effects does not preclude the existence of other effects. One embodiment of the present invention does not necessarily have all of these effects. Effects other than these can be extracted from the description in the specification, drawings, and claims.

[0025] FIG. 1A is a top view showing an example of the configuration of a battery module, and FIG. 1B is a cross-sectional view showing the example of the configuration of a battery module. FIG. 2 is a cross-sectional view showing the example of the configuration of a battery module. FIGS. 3A to 3E are diagrams explaining a method of manufacturing a battery module. FIGS. 4A to 4C are diagrams explaining a method of manufacturing a battery module. FIGS. 5A and 5B are diagrams explaining a method of manufacturing a battery module. FIGS. 6A and 6B are diagrams explaining a method of manufacturing a battery module. FIG. 7 is a schematic diagram explaining a method of manufacturing a battery module. FIGS. 8A and 8B are diagrams explaining a method of manufacturing a battery module. FIGS. 9A and 9B are diagrams explaining a method of manufacturing a battery module. FIGS. 10A to 10C are side views explaining an example of the configuration of a battery module. FIGS. 11A to 11C are side views explaining an example of the configuration of a battery module. FIGS. 12A and 12B are side views explaining an example of the configuration of a battery module. FIGS. 13A to 13C are diagrams explaining an example of the configuration of a battery. FIGS. 14A to 14C are diagrams explaining an example of the configuration of a battery. 15A to 15C are diagrams illustrating an example of the configuration of a battery. FIG. 16 is a diagram illustrating a method for processing a film. FIGS. 17A to 17E are diagrams illustrating a method for processing a film. FIGS. 18A and 18B are diagrams illustrating a method for processing a film. FIG. 19A is a top view illustrating an example of the configuration of an electronic device, FIG. 19B is a cross-sectional view illustrating an example of the configuration of an electronic device, and FIG. 19C is a perspective view illustrating an example of the configuration of an electronic device. FIG. 20A is a cross-sectional view illustrating an example of the configuration of an electronic device, FIG. 20B is a cross-sectional view illustrating an example of the configuration of an integrated substrate, and FIG. 20C is a perspective view illustrating an example of the configuration of an integrated substrate. FIG. 21A is a cross-sectional view illustrating an example of the configuration of an integrated substrate, and FIG. 21B is a perspective view illustrating an example of the configuration of an integrated substrate. FIG. 22 is a perspective view illustrating an example of the configuration of a control circuit unit. FIGS. 23A to 23C are block diagrams illustrating an example of the configuration of an electronic device. FIGS. 24A and 24B are circuit diagrams illustrating an example of the configuration of an electronic device.

[0026] The embodiments will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it will be readily understood by those skilled in the art that various changes can be made in form and detail without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the description of the embodiments shown below.

[0027] In the configuration of the invention described below, the same parts or parts having similar functions are denoted by the same reference numerals in different drawings, and repeated explanations thereof will be omitted. Furthermore, when referring to similar functions, the same hatching pattern may be used and no particular reference numeral may be assigned.

[0028] Furthermore, for ease of understanding, the position, size, range, etc. of each component shown in the drawings may not represent the actual position, size, range, etc. Therefore, the disclosed invention is not necessarily limited to the position, size, range, etc. disclosed in the drawings.

[0029] In this specification, the ordinal numbers such as "first" and "second" are used for convenience and do not limit the number of components or the order of the components (for example, the order of processes or the order of stacking). Furthermore, an ordinal number assigned to a component in one part of this specification may not match an ordinal number assigned to the same component in another part of this specification or in the claims.

[0030] It should be noted that the terms "film" and "layer" can be interchangeable depending on the circumstances. For example, the term "conductive layer" can be changed to the term "conductive film." Or, for example, the term "insulating film" can be changed to the term "insulating layer."

[0031] In this specification, terms indicating position, such as "above," "below," "upward," or "below" may be used for convenience in describing the positional relationship between components with reference to the drawings. Furthermore, the positional relationship between components changes as appropriate depending on the direction in which each configuration is depicted. Therefore, the terms are not limited to those described in this specification, and can be rephrased appropriately depending on the situation. For example, the expression "insulator located above a conductor" can be rephrased as "insulator located below a conductor" by rotating the orientation of the drawing 180 degrees.

[0032] In this specification, the terms "above" and "below" do not limit the positional relationship of components to "directly above" or "directly below."

[0033] Furthermore, the terms "electrode" and "wiring" used in this specification and the like do not limit the functionality of these components. For example, an "electrode" may be used as part of a "wiring," and vice versa. Furthermore, the terms "electrode" and "wiring" also include cases where multiple "electrodes" and "wirings" are integrally formed.

[0034] Furthermore, the functions of "source" and "drain" may be interchanged when transistors of different polarities are used, or when the direction of current flow changes during circuit operation, etc. For this reason, the terms "source" and "drain" may be used interchangeably in this specification.

[0035] In this specification, "connection" includes, as an example, "electrical connection." Note that the term "electrical connection" is sometimes used to define the connection relationship between circuit elements as an object. Furthermore, "electrical connection" includes "direct connection" and "indirect connection." "A and B are directly connected" means that A and B are connected without the intervention of a circuit element (e.g., a transistor, a switch, etc.; note that wiring is not a circuit element). On the other hand, "A and B are indirectly connected" means that A and B are connected via one or more circuit elements. Note that A and B represent objects such as elements, circuits, wiring, electrodes, terminals, semiconductor layers, and conductive layers.

[0036] For example, assuming that a circuit including A and B is operating, if there is a time during the operation of the circuit when an electrical signal is exchanged or an interaction of electrical potential occurs between A and B, then it can be defined that "A and B are indirectly connected" as objects. Note that even if there is a time during the operation of the circuit when no electrical signal is exchanged or an interaction of electrical potential occurs between A and B, it can still be defined that "A and B are indirectly connected" as long as there is a time during the operation of the circuit when an electrical signal is exchanged or an interaction of electrical potential occurs between A and B.

[0037] An example of a case where "A and B are indirectly connected" is when A and B are connected via the source and drain of one or more transistors. On the other hand, an example of a case where it cannot be said that "A and B are indirectly connected" is when an insulator is present in the path from A to B. Specifically, there are cases where a capacitive element is connected between A and B, and cases where a gate insulating film of a transistor is present between A and B. Therefore, it cannot be said that "the gate (A) of a transistor and the source or drain (B) of the transistor are indirectly connected."

[0038] Another example of a case where it cannot be said that "A and B are indirectly connected" is when multiple transistors are connected via their sources and drains to the path from A to B, and a constant potential V is supplied to a node between one transistor and another transistor from a power supply, GND, etc.

[0039] In this specification and elsewhere, flexibility refers to the property of an object being soft and bendable, i.e., the property of an object being able to deform in response to an external force applied to the object, regardless of whether or not the object has elasticity or the ability to return to its original shape before deformation.

[0040] For example, a flexible electronic device can deform in response to an external force. A flexible electronic device can be used while fixed in a deformed state, or can be used after repeatedly deforming. A flexible display device (also referred to as a flexible display device, flexible display device, flexible display, etc.) can deform in response to an external force. A flexible display device can be used while fixed in a deformed state, or can be used after repeatedly deforming, or can be used in an undeformed state. A flexible battery (also referred to as a flexible battery, flexible battery, flexible battery, etc.) can deform in response to an external force. A flexible battery can be used while fixed in a deformed state, or can be used after repeatedly deforming, or can be used in an undeformed state. A flexible substrate (also referred to as a flexible substrate, flexible substrate, etc.) can deform in response to an external force. A flexible substrate can be used while fixed in a deformed state, or can be used after repeatedly deforming, or can be used in an undeformed state. Note that the above phrase "deform in response to an external force" refers to deformation by an average adult's hand without requiring excessive force. Flexibility can be quantified as deformation of an object due to an external force using a testing machine (such as a tensile testing machine or a compression testing machine) capable of measuring stress-strain.

[0041] Furthermore, in this specification, when an object is described as being flexible, it means that at least a part of the object is flexible. In other words, a flexible object may have a non-flexible part (also called a hard part).

[0042] In this specification, "high flexibility" means that when two objects are deformed by the same external force, the object that deforms more is said to be the object with high flexibility. Also, when a first part and a second part of an object are deformed by the same external force, the part that deforms more is said to be the part with high flexibility.

[0043] Embodiment 1 In this embodiment, a structural example of a battery module according to one embodiment of the present invention will be described.

[0044] A battery module according to one embodiment of the present invention includes a flexible substrate and a battery module. The flexible substrate includes a metal layer that functions as an electrical wiring. The battery module includes an exterior body, and electrodes (positive and negative electrodes) and connection terminals (positive and negative terminals) that are provided in a space surrounded by the exterior body.

[0045] In the battery section, the electrodes are connected to connection terminals. The connection terminals are connected to a metal layer of the flexible substrate through an opening in the exterior body that overlaps the flexible substrate. The metal layer is preferably located between the two resin layers.

[0046] By having the configuration described above, it is possible to connect the flexible substrate portion and the battery portion without using a connection terminal protruding from the end of the outer casing, and therefore the battery module of one embodiment of the present invention can have a space-saving configuration.

[0047] The connection terminal has a resin layer on the surface that contacts the exterior body, and is bonded to the exterior body via the resin layer (connection portion). The resin layer is provided around the opening, and can prevent the electrolyte from leaking from the periphery of the connection portion.

[0048] [Battery Module] FIGS. 1A, 1B, and 2 are diagrams showing an example of a battery module according to one embodiment of the present invention.

[0049] Fig. 1A is a top view of the battery module 20, Fig. 1B is a schematic cross-sectional view taken along dashed line X1-X2 in Fig. 1A, and Fig. 2 is a schematic cross-sectional view taken along dashed line X3-X4 in Fig. 1A.

[0050] 1A , the battery module 20 includes a battery section 100 and a flexible substrate section 200. The flexible substrate section 200 may also be called a flexible printed circuit (FPC) substrate section or a flexible substrate. The battery section 100 may also be called a battery, a cell, or a power storage section.

[0051] As shown in FIGS. 1A, 1B, and 2, the battery module 100 includes a positive electrode 120, a negative electrode 130, an exterior body 150, a positive electrode terminal 160, and a negative electrode terminal 170. The positive electrode 120, the negative electrode 130, the positive electrode terminal 160, and the negative electrode terminal 170 are provided in a space surrounded by the exterior body 150. The positive electrode 120 includes a positive electrode current collector 121 and a positive electrode active material layer 122. The negative electrode 130 includes a negative electrode current collector 131 and a negative electrode active material layer 132. The exterior body 150 includes a resin layer 153, a metal layer 152, and a resin layer 151. The positive electrode terminal 160 includes a metal layer 161, a connection portion 162, and a resin layer 163.

[0052] As shown in FIGS. 1B and 2, in the exterior body 150, a resin layer 153, a metal layer 152 and another resin layer 153 are laminated in this order from the inside to the outside of the battery module 100.

[0053] As shown in FIG. 1B , in the positive electrode terminal 160 , a connection portion 162 is provided on one surface of the metal layer 161 and inside an opening in the resin layer 163 .

[0054] 1B , in the battery module 100, the positive electrode 120 and the negative electrode 130 have an overlapping region, which is referred to as a laminated portion 110. In the laminated portion 110, the positive electrode active material layer 122 and the negative electrode active material layer 132 overlap with a separator (not shown) interposed therebetween. The positive electrode current collector 121 has a tab portion 61 protruding from the laminated portion 110, and the positive electrode current collector 121 is connected to a metal layer 161 of a positive electrode terminal 160 at the tab portion 61.

[0055] 1B , in the battery module 100, the resin layer 163 of the positive electrode terminal 160 is connected to the resin layer 153 of the exterior body 150. The resin layer 163 and the resin layer 153 may be connected to each other using an adhesive, or may be bonded by heat fusion using a thermoplastic resin for both the resin layer 163 and the resin layer 153. For example, a polypropylene separator (PP) may be used as the thermoplastic resin.

[0056] As shown in FIGS. 1B and 2, the flexible substrate section 200 has a resin layer 201 , a metal layer 202 , a resin layer 203 , a metal layer 204 , and a resin layer 205 .

[0057] 1B and 2, in flexible substrate unit 200, metal layer 202 has a region located between resin layer 201 and resin layer 203. Metal layer 204 has a region located between resin layer 203 and resin layer 205. Metal layer 202 and metal layer 204 may have an overlapping region, but do not necessarily have an overlapping region. Note that metal layer 202 and metal layer 204 preferably function as wiring layers in flexible substrate unit 200.

[0058] 1B and 2 , one surface of flexible substrate unit 200 is connected to battery unit 100. Specifically, from one surface of flexible substrate unit 200 to the other surface, resin layer 205, metal layer 204, resin layer 203, metal layer 202, and resin layer 201 are stacked in this order, and resin layer 205 is connected to resin layer 151 of exterior body 150 via adhesive layer 210.

[0059] As shown in FIG. 1B , one surface of the flexible substrate unit 200 is connected to the positive electrode terminal 160 of the battery unit 100. Specifically, inside an opening 51 extending from the metal layer 204 to the metal layer 161, the opening 51 is provided in the resin layer 205, the resin layer 151, the metal layer 152, the resin layer 153, and the resin layer 163. The opening 51 connects the metal layer 204 to the metal layer 161 via a connecting portion 162. The connecting portion 162 is conductive and may be made of, for example, a conductive resin. In this manner, the positive electrode current collector 121 of the battery unit 100 is electrically connected to the metal layer 204. The metal layer 204 and the metal layer 161 may be connected by welding without using a conductive resin. Examples of welding methods that can be used include ultrasonic welding and laser welding.

[0060] As shown in FIG. 2 , in the negative electrode terminal 170 , a connection portion 172 is provided on one surface of the metal layer 171 and inside an opening in the resin layer 173 .

[0061] As shown in FIG. 2 , the negative electrode current collector 131 has a tab portion 62 protruding from the laminated portion 110, and the negative electrode current collector 131 is connected to a metal layer 171 of the negative electrode terminal 170 at the tab portion 62.

[0062] 2, in the battery module 100, the resin layer 173 of the negative electrode terminal 170 is connected to the resin layer 153 of the exterior body 150. As with the positive electrode terminal 160, the resin layer 173 and the resin layer 153 may be bonded together using an adhesive, or they may be bonded together by heat fusion using a thermoplastic resin for both the resin layer 173 and the resin layer 153. For example, PP may be used as the thermoplastic resin.

[0063] As shown in FIG. 2 , one surface of the flexible substrate unit 200 is connected to the negative electrode terminal 170 of the battery unit 100. Specifically, inside an opening 52 extending from the metal layer 202 to the metal layer 171, the opening 52 is provided in the resin layer 203, the metal layer 204, the resin layer 205, the resin layer 151, the metal layer 152, the resin layer 153, and the resin layer 173. The opening 52 connects the metal layer 202 to the metal layer 171 via a connecting portion 172. The connecting portion 172 is conductive and may be made of, for example, a conductive resin. In this manner, the negative electrode current collector 131 of the battery unit 100 is electrically connected to the metal layer 202. The metal layer 202 and the metal layer 171 may be connected by welding without using a conductive resin. Examples of welding methods that can be used include ultrasonic welding and laser welding.

[0064] 1A, 1B, and 2 show an example of a configuration in which the positive electrode current collector 121 and the metal layer 204 are connected, but the configuration may also be such that the positive electrode current collector 121 and the metal layer 202 are connected, or similarly, the configuration may also be such that the negative electrode current collector 131 and the metal layer 204 are connected.

[0065] [Method for Manufacturing Battery Module] An example of a method for manufacturing a battery module of one embodiment of the present invention will be described with reference to FIGS. 3A to 9B.

[0066] 3A shows a top view of a positive electrode current collector 121, FIG. 3B shows a separator 140, FIG. 3C shows a negative electrode current collector 131, FIG. 3D1 shows a positive electrode terminal 160, FIG. 3D2 shows a negative electrode terminal 170, and FIG. 3E shows a top view of a film-like exterior body 150. The positive electrode terminal 160 has a connection portion 162 and a resin layer 163 on a metal layer 161, and the connection portion 162 is located inside an opening of the resin layer 163. Similarly, the negative electrode terminal 170 has a connection portion 172 and a resin layer 173 on a metal layer 171, and the connection portion 172 is located inside an opening of the resin layer 173.

[0067] 3E, exterior body 150 has openings 155 and 156. Opening 155 is provided at a position corresponding to opening 51 shown in FIGS. 1A and 1B, and opening 156 is provided at a position corresponding to opening 52 shown in FIGS. 1A and 2.

[0068] The protruding portion of the positive electrode current collector 121 (the portion indicated by the dashed line in FIG. 3A) and the protruding portion of the negative electrode current collector 131 (the portion indicated by the dashed line in FIG. 3C) are called tab portions.

[0069] FIG. 4A is a perspective view illustrating the positional relationship between a positive electrode current collector 121, a positive electrode active material layer 122, a separator 140, a negative electrode current collector 131, and a negative electrode active material layer 132. FIG.

[0070] 4A , the positive electrode active material layer 122 is provided on the positive electrode current collector 121 other than the tab portion. Similarly, the negative electrode active material layer 132 is provided on the negative electrode current collector 131 other than the tab portion. The positive electrode active material layer 122 is overlapped with the negative electrode active material layer 132 with the separator 140 interposed therebetween. In other words, the positive electrode active material layer 122 is overlapped so as to face the negative electrode active material layer 132 with the separator 140 interposed therebetween.

[0071] Next, as shown in Fig. 4B, the tab portion of the positive electrode current collector 121 is connected to a positive electrode terminal 160, and the tab portion of the negative electrode current collector 131 is connected to a negative electrode terminal 170. The state after connection shown in Fig. 4C is called a laminate, and the laminate has a laminate portion 110.

[0072] Next, as shown in Fig. 5A, exterior body 150 is placed on the laminate described in Fig. 4C. At this time, opening 155 overlaps with an opening in resin layer 163 and they are connected at adhesive portion 155a. Similarly, opening 156 overlaps with an opening in resin layer 173 and they are connected at adhesive portion 156a. In this way, battery module 100a in the process of being produced is produced, as shown in Fig. 5B.

[0073] The flexible substrate unit 200 will be described with reference to FIGS. 6A and 6B.

[0074] Fig. 6A is a perspective view illustrating the connection relationship between resin layer 201, metal layer 202, resin layer 203, metal layer 204, and resin layer 205 of flexible substrate unit 200. Fig. 6B is a top view of flexible substrate unit 200 in which resin layer 201, metal layer 202, resin layer 203, metal layer 204, and resin layer 205 are laminated. As shown in Fig. 6B, flexible substrate unit 200 has metal layer 204 exposed at opening 251 and metal layer 202 exposed at opening 252. Opening 251 is provided at a position corresponding to opening 51 shown in Figs. 1A and 1B, and opening 252 is provided at a position corresponding to opening 52 shown in Figs. 1A and 2.

[0075] Next, as shown in Fig. 7, adhesive layer 210 is provided on flexible substrate 200, and battery unit 100a in the process of being fabricated is placed on top of adhesive layer 210. Note that battery unit 100a in the process of being fabricated shown in Fig. 7 is the battery unit 100a in the process of being fabricated described in Fig. 5B, rotated so that the laminate is on top.

[0076] 7, adhesive layer 210 has openings 211 and 212. Opening 211 is provided so that opening 251 faces inward, and opening 212 is provided so that opening 252 faces inward.

[0077] 7, connecting portion 162 is connected to metal layer 204 on the inside of opening 251 and opening 211. Connecting portion 172 is connected to metal layer 202 on the inside of opening 252 and opening 212. The state after the above connection is shown in FIG. 8A.

[0078] Next, as shown in Figure 8B, the exterior body 150 of the battery module 100a in the process of being fabricated is folded back at the position indicated by the two-dot chain line in Figure 8A, and two sides are sealed to form sealed sections 154a and 154b. In sealed sections 154a and 154b, the resin layers 153 of the exterior body 150 may be bonded together using an adhesive, or may be bonded by heat fusion using a thermoplastic resin for the resin layer 153. PP, for example, may be used as the thermoplastic resin. The state in which the two sides are sealed in this manner is referred to as the battery module 100b in the process of being fabricated.

[0079] Next, as shown in FIG. 9A, an electrolyte is poured into one unsealed side of the exterior body 150 of the partially fabricated battery unit 100b.

[0080] After the injection of the electrolyte solution as described with reference to FIG. 9A, the battery module 100 is produced by sealing the battery module 100 at the sealing portion 154c as shown in FIG. 9B.

[0081] A side view of the battery module 20 thus fabricated is shown in Fig. 10A. Modified examples of the exterior body 150 will be described with reference to Figs. 10A to 10C.

[0082] The battery unit 100 shown in Figure 10A is made using one outer casing 150, but it may also be made using two outer casings 150x (outer casing 150x1, outer casing 150x2), as in the battery unit 100x shown in Figure 10B.

[0083] 10A and the like is fabricated using a flat exterior body 150, but it may also be fabricated using an exterior body 150y2 having an embossed shape, as in the battery unit 100y shown in Fig. 10C. Fig. 10C shows an example in which an exterior body 150y1 without an embossed shape is used on the flexible substrate unit 200 side, and an exterior body 150y2 with an embossed shape is used on the opposite side.

[0084] As such, the battery module 20 shown in Fig. 10A may be used as a battery module of one embodiment of the present invention. Alternatively, the battery module 20x shown in Fig. 10B may be used, which includes a battery unit 100x and a flexible substrate unit 200. Alternatively, the battery module 20y shown in Fig. 10C may be used, which includes a battery unit 100y and a flexible substrate unit 200.

[0085] 1A to 10A include one battery module 100 and one flexible substrate module 200, but the battery module of one embodiment of the present invention is not limited to this. Modifications of the battery module 20 will be described with reference to FIGS. 11A to 11C . For example, as shown in FIG. 11A , a battery module may include two or more battery modules 100 and one flexible substrate module 200x.

[0086] In the above, the flexible substrate unit 200x may be configured to have a partially flexible region. For example, if the flexible substrate unit 200x has a flexible region 220, the flexible substrate unit 200x can be partially bent as shown in FIG. 11B . In this case, the flexible substrate unit 200x may have a region other than the region 220 that is not flexible. For example, the flexible substrate unit 200x may have a thin thickness in the region 220 and a thick thickness in the other regions, and a control circuit unit (described later) may be provided in the thicker region.

[0087] Alternatively, if a flexible battery unit 100y is used instead of the two battery units 100 shown in Figure 11B, it becomes possible to bend the flexible substrate unit 200x and the battery unit 100y, as shown in Figure 11C.

[0088] 12A and 12B are diagrams illustrating an example configuration of a battery module having a control circuit board. In addition to the configuration described in FIG. 11A , a configuration having multiple control circuit units on a flexible substrate unit 200x is also possible. For example, as shown in FIG. 12A , a battery module having a control circuit unit can be configured with two or more battery units 100 (battery unit 100A, battery unit 100B) and one flexible substrate unit 200x, and further provided with two or more control circuit units 300 (control circuit unit 300A, control circuit unit 300B). For example, by providing the control circuit unit 300A facing the battery unit 100A across the flexible substrate unit 200x and providing the control circuit unit 300B facing the battery unit 100B, the battery module having the control circuit unit can be bent. As shown in FIG. 12B , a flexible battery unit 100y can also be used as the battery unit.

[0089] The configuration having a plurality of battery units 100, a plurality of control circuit units 300, and a flexible substrate unit 200, which has been described with reference to FIGS. 12A and 12B, will be described in detail in a later embodiment.

[0090] [Example of Electrode Stack] Hereinafter, an example of the structure of the stack will be described.

[0091] In this embodiment, the configuration examples shown in Figures 1B and 2 illustrate an example of a laminate having two double-sided coated positive electrodes, one double-sided coated negative electrode, and two single-sided coated negative electrodes. Furthermore, the manufacturing method illustrated in Figures 3A to 9B illustrates an example of a laminate having one single-sided coated positive electrode and one single-sided coated negative electrode. The number of positive electrodes, the number of negative electrodes, and the selection of single-sided coated electrodes and double-sided coated electrodes for the laminate included in the battery module of one embodiment of the present invention are not limited to the above examples.

[0092] 13A shows an example of a laminate having one double-sided coated positive electrode in which a positive electrode active material layer 122 is provided on both sides of a positive electrode current collector 121, and two single-sided coated negative electrodes in which a negative electrode active material layer 132 is provided on one side of a negative electrode current collector 131. In more detail, the negative electrode current collector 131, negative electrode active material layer 132, separator 140, positive electrode active material layer 122, positive electrode current collector 121, positive electrode active material layer 122, separator 140, negative electrode active material layer 132, and negative electrode current collector 131 are arranged in this order. A cross-sectional view of this laminate structure cut along plane 180 is shown in FIG. 13B.

[0093] 13A shows an example in which two separators are used, it is also possible to use a structure in which one separator is folded and both ends are sealed to form a bag shape, and positive electrode current collector 121 is housed between the folded separators. Positive electrode active material layers 122 are formed on both sides of positive electrode current collector 121 housed in the bag-shaped separator.

[0094] It is also possible to provide anode active material layers 132 on both sides of the anode current collector 131. Fig. 13C shows an example of a secondary battery in which three anode current collectors 131 having anode active material layers 132 on both sides, four cathode current collectors 121 having cathode active material layers 122 on both sides, and eight separators 140 are sandwiched between two anode current collectors 131 having anode active material layers 132 on only one side. In this case, four pouch-shaped separators may be used instead of eight separators.

[0095] Increasing the number of layers can increase the capacity of the secondary battery. Furthermore, by providing the positive electrode active material layers 122 on both sides of the positive electrode current collector 121 and the negative electrode active material layers 132 on both sides of the negative electrode current collector 131, the thickness of the secondary battery can be reduced.

[0096] 14A shows a secondary battery formed by providing a positive electrode active material layer 122 on only one surface of a positive electrode current collector 121 and a negative electrode active material layer 132 on only one surface of a negative electrode current collector 131. Specifically, the negative electrode active material layer 132 is provided on one surface of the negative electrode current collector 131, and a separator 140 is laminated so as to be in contact with the negative electrode active material layer 132. The surface of the separator 140 not in contact with the negative electrode active material layer 132 is in contact with the positive electrode active material layer 122 of the positive electrode current collector 121 on one surface of which the positive electrode active material layer 122 is formed. Another positive electrode current collector 121, on one surface of which the positive electrode active material layer 122 is formed, is in contact with the surface of the positive electrode current collector 121. The positive electrode current collectors 121 are arranged so that the surfaces of the positive electrode current collectors 121 on which the positive electrode active material layer 122 is not formed face each other. Then, a separator 140 is further formed, and the negative electrode current collector 131 having the negative electrode active material layer 132 formed on one surface thereof is laminated so that the negative electrode active material layer 132 is in contact with the separator. A cross-sectional view of the laminated structure of Fig. 14A cut along a plane 181 is shown in Fig. 14B.

[0097] Although two separators are used in FIG. 14A, one separator may be folded and sealed at both ends to form a bag, and two positive electrode current collectors 121, each having a positive electrode active material layer 122 disposed on one side thereof, may be sandwiched between the separators.

[0098] Fig. 14C shows a diagram in which a plurality of the laminated structures of Fig. 14A are stacked. In Fig. 14C, the surfaces of the negative electrode current collectors 131 on which the negative electrode active material layers 132 are not formed face each other. Fig. 14C shows a state in which 12 positive electrode current collectors 121, 12 negative electrode current collectors 131, and 12 separators 140 are stacked.

[0099] A stacked structure in which a positive electrode active material layer 122 is provided on only one side of a positive electrode current collector 121 and a negative electrode active material layer 132 is provided on only one side of a negative electrode current collector 131 results in a thicker secondary battery compared to a structure in which a positive electrode active material layer 122 is provided on both sides of a positive electrode current collector 121 and a negative electrode active material layer 132 is provided on both sides of a negative electrode current collector 131. However, the side of the positive electrode current collector 121 on which the positive electrode active material layer 122 is not formed faces the side of another positive electrode current collector 121 on which the positive electrode active material layer 122 is not formed, so that the current collectors come into contact with each other. Similarly, the side of the negative electrode current collector 131 on which the negative electrode active material layer 132 is not formed faces the side of another negative electrode current collector 131 on which the negative electrode active material layer 132 is not formed, so that the current collectors come into contact with each other. For example, when a treatment for enhancing slidability is applied to the surface of the positive electrode current collector 121 on which the positive electrode active material layer 122 is not formed and / or the surface of the negative electrode current collector 131 on which the negative electrode active material layer 132 is not formed, the surfaces where the current collectors are in contact with each other can be made to slide easily without a large frictional force acting on the surfaces where the current collectors are in contact with each other. In other words, when the secondary battery is bent, the current collectors slide inside the secondary battery, making the secondary battery easier to bend. Examples of treatments that can be applied to the current collectors to enhance slidability include coating with a fluororesin (such as polytetrafluoroethylene), coating with graphene, and coating with a graphene compound.

[0100] 13 and 14, the positive electrode current collectors 121 are stacked and all of them are fixed and electrically connected. Similarly, the negative electrode current collectors 131 are all fixed and electrically connected.

[0101] Here, it is preferable to fix and electrically connect the positive electrode terminal 160 and the plurality of positive electrode current collectors 121. Similarly, it is preferable to fix and electrically connect the negative electrode terminal 170 and the plurality of negative electrode current collectors 131. By connecting the plurality of current collectors and electrode leads in this way, the production can be carried out efficiently.

[0102] Furthermore, the separator 140 preferably has a shape that makes it difficult for the positive electrode 120 and the negative electrode 130 to electrically short-circuit. For example, as shown in FIG. 15A , it is preferable to make the width of each separator 140 larger than that of the positive electrode 120 and the negative electrode 130, because this makes it difficult for the positive electrode 120 and the negative electrode 130 to come into contact even when the relative positions of the positive electrode 120 and the negative electrode 130 are shifted due to deformation such as bending. Furthermore, it is preferable to make one separator 140 shaped like an accordion as shown in FIG. 15B or to make one separator 140 shaped so that the positive electrode 120 and the negative electrode 130 are alternately wound around the separator 140 as shown in FIG. 15C, because this prevents contact even when the relative positions of the positive electrode 120 and the negative electrode 130 are shifted. Furthermore, FIGS. 15B and 15C show examples in which a portion of the separator 140 is provided so as to cover the side surface of the stacked structure of the positive electrode 120 and the negative electrode 130.

[0103] 15 does not show the details of the positive electrodes 120 and the negative electrodes 130, but the method for forming them may be as described above. Also, although an example in which the positive electrodes 120 and the negative electrodes 130 are alternately arranged one by one has been shown here, a configuration in which two positive electrodes 120 or two negative electrodes 130 are continuous with each other may also be used, as shown in FIG.

[0104] Note that the electrodes included in the battery module of one embodiment of the present invention are not limited to a positive electrode and a negative electrode, and a reference electrode (also referred to as a reference electrode) may also be provided. When a reference electrode is provided, an opening for the reference electrode may be provided in addition to the openings 51 and 51 described with reference to FIGS. 1A to 2 , and the reference electrode may be connected from the inside to the outside of the battery module 100 (for example, the flexible substrate portion 200).

[0105] Each component of a battery module according to one embodiment of the present invention, such as a negative electrode, a positive electrode, an electrolyte, a separator, and an exterior body, will be described in detail below.

[0106] [Negative Electrode] The negative electrode has a negative electrode active material layer and a negative electrode current collector. The negative electrode active material layer has a negative electrode active material, and may further have a conductive material and a binder.

[0107] The current collector can be, for example, a metal foil. The negative electrode can be formed by applying a slurry to a metal foil and drying it. Pressing may be performed after drying. The negative electrode is formed by forming an active material layer on a current collector.

[0108] The term "slurry" refers to a material liquid used to form an active material layer on a current collector, and contains an active material, a binder, and a solvent, and preferably further contains a conductive material. The slurry is also called an electrode slurry or an active material slurry, and when forming a negative electrode active material layer, it is also called a negative electrode slurry.

[0109] [Negative Electrode Active Material] As the negative electrode active material, for example, a carbon material or an alloy-based material can be used.

[0110] Examples of carbon materials that can be used include graphite (natural graphite, artificial graphite), graphitizable carbon (soft carbon), non-graphitizable carbon (hard carbon), carbon fiber (carbon nanotube), graphene, and carbon black.

[0111] Examples of graphite include artificial graphite and natural graphite. Examples of artificial graphite include mesocarbon microbeads (MCMB), coke-based artificial graphite, and pitch-based artificial graphite. Here, spherical graphite having a spherical shape can be used as the artificial graphite. For example, MCMB may have a spherical shape and is therefore preferred. Furthermore, it is relatively easy to reduce the surface area of ​​MCMB, and this may be preferred. Examples of natural graphite include flake graphite and spherical natural graphite.

[0112] When lithium ions are inserted into graphite (when a lithium-graphite intercalation compound is formed), graphite exhibits a potential as low as that of metallic lithium (0.05 V to 0.3 V vs. Li / Li ＋This allows lithium-ion batteries using graphite to exhibit high operating voltages. Graphite is also preferred because it has advantages such as a relatively high capacity per unit volume, relatively small volume expansion, low cost, and greater safety compared to lithium metal.

[0113] The non-graphitizable carbon can be obtained by calcining a synthetic resin such as a phenolic resin or a plant-derived organic material. The non-graphitizable carbon contained in the negative electrode active material of the lithium-ion battery according to one embodiment of the present invention preferably has a (002) plane spacing measured by X-ray diffraction (XRD) of 0.34 nm or more and 0.50 nm or less, and more preferably 0.35 nm or more and 0.42 nm or less.

[0114] In addition, the negative electrode active material can be an element capable of undergoing a charge-discharge reaction through alloying and dealloying reactions with lithium. For example, a material containing at least one of silicon, tin, gallium, aluminum, germanium, lead, antimony, bismuth, silver, zinc, cadmium, indium, etc. can be used. These elements have a larger capacity than carbon, and silicon in particular has a high theoretical capacity of 4200 mAh / g. For this reason, it is preferable to use silicon as the negative electrode active material. Alternatively, compounds containing these elements may be used. For example, SiO, Mg ２ Si, Mg ２ Ge, SnO, SnO ２ , Mg ２ Sn, SnS ２ , V ２ Sn ３ , FeSn ２ , CoSn ２ , Ni ３ Sn ２ , Cu ６ Sn ５ , Ag ３ Sn, Ag ３ Sb, Ni ２ MnSb, CeSb ３ , LaSn ３ , La ３ Co ２ Sn ７ , CoSb ３, InSb, SbSn, etc. Here, elements capable of undergoing charge-discharge reactions by alloying / dealloying reactions with lithium, and compounds containing such elements, are sometimes referred to as alloy-based materials.

[0115] In this specification, "SiO" refers to, for example, silicon monoxide. ｘ Here, x preferably has a value of 1 or close to 1. For example, x is preferably 0.2 or more and 1.5 or less, and more preferably 0.3 or more and 1.2 or less.

[0116] Titanium dioxide (TiO ２ ), lithium titanium oxide (Li ４ Ti ５ O １２ ), lithium-graphite intercalation compound (Li ｘ C ６ ), niobium pentoxide (Nb ２ O ５ ), tungsten dioxide (WO ２ ), molybdenum dioxide (MoO ２ ) and other oxides can be used.

[0117] In addition, as the negative electrode active material, a nitride of lithium and a transition metal, Li ３ Li with N-type structure ３−ｘ M ｘ N (M=Co, Ni, Cu) can be used. For example, Li ２．６ Co ０．４ N has a large discharge capacity (900 mAh / g, 1890 mAh / cm ３ ) and is preferred.

[0118] When a nitride of lithium and a transition metal is used, lithium ions are contained in the negative electrode active material, so V, which does not contain lithium ions, is used as the positive electrode active material. ２ O ５ , Cr ３ O ８ It is preferable that the material can be combined with a material such as the above. Even when a material containing lithium ions is used as the positive electrode active material, it is possible to use a nitride of lithium and a transition metal as the negative electrode active material by first desorbing the lithium ions contained in the positive electrode active material.

[0119] Furthermore, a material that undergoes a conversion reaction can also be used as the negative electrode active material. For example, a transition metal oxide that does not form an alloy with lithium, such as cobalt oxide (CoO), nickel oxide (NiO), or iron oxide (FeO), can be used as the negative electrode active material. Further examples of materials that undergo a conversion reaction include Fe ２ O ３ , CuO, Cu ２ O, RuO ２ , Cr ２ O ３ oxides such as CoS ０．８９ , sulfides such as NiS and CuS, Zn ３ N ２ , Cu ３ N, Ge ３ N ４ Nitrides such as NiP ２ , FeP ２ , CoP ３ Phosphides such as FeF ３ , BiF ３ Fluorides such as:

[0120] Although one type of anode active material from among the above-described anode active materials can be used, a combination of two or more types of anode active materials can also be used, such as a combination of a carbon material and silicon, or a combination of a carbon material and silicon monoxide.

[0121] The negative electrode active material may be pre-doped with lithium. The pre-doping method for lithium may involve forming a lithium layer on the surface of the negative electrode active material layer by sputtering. Alternatively, the negative electrode active material layer may be pre-doped with lithium by providing a lithium foil on the surface of the negative electrode active material layer. Alternatively, a pre-doping battery may be fabricated using a dummy positive electrode containing lithium, and the negative electrode active material layer may be pre-doped with lithium by charging the battery.

[0122] Alternatively, the negative electrode may be one that does not have a negative electrode active material at the end of the battery fabrication. A negative electrode that does not have a negative electrode active material may be, for example, a negative electrode that has only a negative electrode current collector at the end of the battery fabrication, in which lithium ions released from the positive electrode active material upon charging the battery are deposited as lithium metal on the negative electrode current collector to form a negative electrode active material layer. A battery using such a negative electrode is sometimes called a negative electrode-free (anode-free) battery, a negative electrode-less (anode-less) battery, or the like.

[0123] When a negative electrode without a negative electrode active material is used, a film for uniforming lithium deposition may be provided on the negative electrode current collector. For example, a solid electrolyte having lithium ion conductivity can be used as the film for uniforming lithium deposition. Examples of solid electrolytes that can be used include sulfide-based solid electrolytes, oxide-based solid electrolytes, and polymer-based solid electrolytes. Among these, polymer-based solid electrolytes are suitable as films for uniforming lithium deposition because they are relatively easy to form uniformly on the negative electrode current collector. Furthermore, for example, a metal film that forms an alloy with lithium can be used as the film for uniforming lithium deposition. For example, a magnesium metal film can be used as the metal film that forms an alloy with lithium. Lithium and magnesium form a solid solution over a wide composition range, making them suitable as films for uniforming lithium deposition.

[0124] Furthermore, when a negative electrode that does not have a negative electrode active material is used, a negative electrode current collector having projections and recesses can be used. When a negative electrode current collector having projections and recesses is used, the recesses of the negative electrode current collector become cavities into which lithium contained in the negative electrode current collector can be easily deposited, and therefore, when lithium is deposited, it is possible to prevent it from forming a dendritic shape.

[0125] [Binder] As the binder, it is preferable to use a rubber material such as styrene-butadiene rubber (SBR), styrene-isoprene-styrene rubber, acrylonitrile-butadiene rubber, butadiene rubber, ethylene-propylene-diene copolymer, etc. Furthermore, as the binder, fluororubber can be used.

[0126] Furthermore, it is preferable to use, for example, a water-soluble polymer as the binder. Examples of the water-soluble polymer that can be used include polysaccharides. Examples of the polysaccharide that can be used include cellulose derivatives such as carboxymethyl cellulose (CMC), methyl cellulose, ethyl cellulose, hydroxypropyl cellulose, diacetyl cellulose, and regenerated cellulose, as well as starch. It is even more preferable to use these water-soluble polymers in combination with the above-mentioned rubber material.

[0127] Alternatively, it is preferable to use, as the binder, materials such as polystyrene, polymethyl acrylate, polymethyl methacrylate (polymethyl methacrylate, PMMA), sodium polyacrylate, polyvinyl alcohol (PVA), polyethylene oxide (PEO), polypropylene oxide, polyimide, polyvinyl chloride, polytetrafluoroethylene, polyethylene, polypropylene, polyisobutylene, polyethylene terephthalate, nylon, polyvinylidene fluoride (PVDF), polyacrylonitrile (PAN), ethylene propylene diene polymer, polyvinyl acetate, and nitrocellulose.

[0128] The binder may be used in combination with two or more of the above.

[0129] For example, a material with a particularly excellent viscosity adjusting effect may be used in combination with other materials. For example, while rubber materials have excellent adhesive strength and elasticity, it may be difficult to adjust the viscosity when mixed with a solvent. In such cases, it is preferable to mix them with a material with a particularly excellent viscosity adjusting effect. For example, a water-soluble polymer may be used as a material with a particularly excellent viscosity adjusting effect. Furthermore, as water-soluble polymers with a particularly excellent viscosity adjusting effect, the above-mentioned polysaccharides, for example, carboxymethyl cellulose (CMC), methyl cellulose, ethyl cellulose, hydroxypropyl cellulose, and diacetyl cellulose, cellulose derivatives such as regenerated cellulose, or starch may be used.

[0130] In addition, the solubility of cellulose derivatives such as carboxymethyl cellulose can be increased by converting them into salts such as sodium or ammonium salts of carboxymethyl cellulose, making them more effective as viscosity adjusters. Higher solubility can also improve dispersibility with active materials or other components when preparing electrode slurries. In this specification, the cellulose and cellulose derivatives used as electrode binders also include their salts.

[0131] Water-soluble polymers stabilize viscosity by dissolving in water, allowing active materials and other materials combined as binders, such as styrene-butadiene rubber, to be stably dispersed in aqueous solutions. Furthermore, the presence of functional groups is expected to facilitate stable adsorption to the surface of active materials. Furthermore, many cellulose derivatives, such as carboxymethyl cellulose, contain functional groups such as hydroxyl or carboxyl groups, and the presence of these functional groups is expected to facilitate interactions between polymers, resulting in widespread coverage of the active material surface.

[0132] When the binder covering or contacting the surface of the active material forms a film, it is expected to function as a passive film and have the effect of suppressing decomposition of the electrolyte. Here, the "passive film" refers to a film with no electrical conductivity or a film with extremely low electrical conductivity. For example, when a passive film is formed on the surface of the active material, it can suppress decomposition of the electrolyte at the battery reaction potential. Furthermore, it is more desirable that the passive film suppresses electrical conductivity while still allowing lithium ions to conduct.

[0133] [Conductive Material] The conductive material, also called a conductivity imparting agent or a conductivity aid, is made of a carbon material. By attaching the conductive material between multiple active materials, the multiple active materials are electrically connected to each other, thereby increasing the conductivity. Note that the term "attachment" does not only refer to physical adhesion between the active material and the conductive material, but also includes cases where a covalent bond is formed, bonding due to van der Waals forces, where the conductive material covers part of the surface of the active material, where the conductive material is embedded in the surface irregularities of the active material, and where the materials are electrically connected even when not in contact with each other.

[0134] The active material layers such as the positive electrode active material layer and the negative electrode active material layer preferably contain a conductive material.

[0135] As the conductive material, for example, one or more of carbon black such as acetylene black and furnace black, graphite such as artificial graphite and natural graphite, carbon fibers such as carbon nanofibers and carbon nanotubes, and graphene compounds can be used.

[0136] Examples of carbon fibers that can be used include mesophase pitch-based carbon fibers and isotropic pitch-based carbon fibers. Carbon nanofibers and carbon nanotubes can also be used as carbon fibers. Carbon nanotubes can be produced by vapor phase growth, for example.

[0137] In this specification and the like, graphene compounds include graphene, multilayer graphene, multigraphene, graphene oxide, multilayer graphene oxide, multi-graphene oxide, reduced graphene oxide, reduced multilayer graphene oxide, reduced multi-graphene oxide, graphene quantum dots, etc. Graphene compounds contain carbon, have a shape such as a plate or sheet, and have a two-dimensional structure formed by six-membered carbon rings. The two-dimensional structure formed by six-membered carbon rings may also be called a carbon sheet. Graphene compounds may have functional groups. Furthermore, graphene compounds preferably have a curved shape. Furthermore, graphene compounds may be rolled up to resemble carbon nanofibers.

[0138] The active material layer may also contain, as a conductive material, metal powder or metal fiber such as copper, nickel, aluminum, silver, or gold, or a conductive ceramic material.

[0139] The content of the conductive material relative to the total amount of the active material layer is preferably 1 wt % or more and 10 wt % or less, and more preferably 1 wt % or more and 5 wt % or less.

[0140] Unlike granular conductive materials such as carbon black, which make point contact with the active material, graphene compounds enable surface contact with low contact resistance, and therefore can improve the electrical conductivity between the granular active material and the graphene compound with a smaller amount than that of ordinary conductive materials. This allows the ratio of the active material in the active material layer to be increased, thereby increasing the discharge capacity of the battery.

[0141] Particulate carbon-containing compounds such as carbon black and graphite, or fibrous carbon-containing compounds such as carbon nanotubes, tend to fill microscopic spaces. Microscopic spaces refer to, for example, the spaces between multiple active materials. By combining a carbon-containing compound that easily fills microscopic spaces with a sheet-like carbon-containing compound such as graphene, which can impart conductivity across multiple particles, the density of the electrode can be increased, resulting in the formation of an excellent conductive path. The battery obtained by the manufacturing method of one embodiment of the present invention has a high capacity density per volume and is stable, making it effective as an in-vehicle battery.

[0142] [Current Collector] As the current collector, a material that has high conductivity and does not alloy with carrier ions such as lithium, such as metals such as stainless steel, gold, platinum, zinc, iron, copper, aluminum, and titanium, and alloys thereof, can be used. The current collector can be appropriately shaped, such as a sheet, a mesh, a punched metal, or an expanded metal.

[0143] Furthermore, a resin current collector can be used as the current collector, which includes, for example, a resin such as polyolefin (polypropylene, polyethylene, etc.), nylon (polyamide), polyimide, vinylon, polyester, acrylic, or polyurethane, and a particulate or fibrous conductive material (also called a conductive filler).

[0144] The conductive material contained in the resin current collector can be one or more of a conductive carbon material and a metal material such as aluminum, titanium, stainless steel, gold, platinum, zinc, iron, or copper. Examples of the conductive carbon material include carbon black such as acetylene black and furnace black, graphite such as artificial graphite and natural graphite, carbon fibers such as carbon nanofibers and carbon nanotubes, graphene, and graphene compounds. When the resin current collector is used as a positive electrode current collector, it is preferable that the resin current collector further contains an antioxidant such as a hindered phenol material.

[0145] Examples of carbon fibers that can be used include mesophase pitch-based carbon fibers and isotropic pitch-based carbon fibers. Carbon nanofibers and carbon nanotubes can also be used as carbon fibers. Carbon nanotubes can be produced by vapor phase growth, for example.

[0146] The conductive material contained in the resin current collector may have an average particle size of 10 nm or more and 10 μm or less, and preferably 30 nm or more and 5 μm or less.

[0147] The current collector preferably has a thickness of 5 μm or more and 30 μm or less.

[0148] The negative electrode current collector is preferably made of a material that does not alloy with carrier ions such as lithium.

[0149] Furthermore, a laminated current collector having a structure in which metal layers are provided on both sides of an organic material film can be used as the current collector. Examples of the organic material film include polypropylene, polyethylene, nylon, and polyethylene terephthalate. Examples of the metal layer include highly conductive materials such as stainless steel, gold, platinum, aluminum, and titanium, as well as alloys thereof. The laminated current collector can be fabricated by bonding an organic material film to a metal foil (metal layer). In this case, an adhesive layer is provided between the organic material film and the metal layer. Alternatively, the laminated current collector can be fabricated by forming metal layers on both sides of the organic material film by a sputtering method, a vapor deposition method, or the like. When the laminated current collector is used as a negative electrode current collector, it is preferable to use copper as the metal layer. Alternatively, when the laminated current collector is used as a positive electrode current collector, it is preferable to use aluminum as the metal layer. Another example of the laminated current collector configuration is one in which a graphene layer is provided instead of the metal layer.

[0150] [Positive electrode] The positive electrode has a positive electrode active material layer and a positive electrode current collector. The positive electrode active material layer contains a positive electrode active material and may further contain at least one of a conductive material and a binder. Note that the positive electrode current collector, conductive material, and binder may be those described in [Negative electrode].

[0151] The current collector can be, for example, a metal foil. The positive electrode can be formed by applying a slurry to a metal foil and drying it. Pressing may be performed after drying. The positive electrode is formed by forming an active material layer on a current collector.

[0152] The slurry is a material liquid used to form an active material layer on a current collector, and refers to a material containing an active material, a binder, and a solvent, preferably further mixed with a conductive material. The slurry is also called an electrode slurry or an active material slurry, and when forming a positive electrode active material layer, it is also called a positive electrode slurry.

[0153] [Positive Electrode Active Material] As the positive electrode active material, at least one of a composite oxide having a layered rock salt structure, a composite oxide having an olivine structure, and a composite oxide having a spinel structure can be used.

[0154] As the composite oxide having a layered rock salt structure, any one or more of lithium cobalt oxide, lithium nickel-cobalt-manganese oxide, lithium nickel-cobalt-aluminate, and lithium nickel-manganese-aluminate can be used. ２ (M1 is one or more selected from nickel, cobalt, manganese, and aluminum), but the coefficients of the composition formula are not limited to integers.

[0155] As the lithium cobalt oxide, for example, any one or more of lithium cobalt oxide having magnesium, lithium cobalt oxide having magnesium and aluminum, lithium cobalt oxide having magnesium, aluminum, and titanium, lithium cobalt oxide having magnesium and nickel, lithium cobalt oxide having magnesium, aluminum, and nickel, lithium cobalt oxide having magnesium, aluminum, titanium, and nickel, lithium cobalt oxide having magnesium and fluorine, lithium cobalt oxide having magnesium, fluorine, and titanium, lithium cobalt oxide having magnesium, fluorine, and aluminum, lithium cobalt oxide having magnesium, fluorine, titanium, and aluminum, lithium cobalt oxide having magnesium, fluorine, and nickel, lithium cobalt oxide having magnesium, fluorine, nickel, and aluminum, lithium cobalt oxide having magnesium, fluorine, aluminum, titanium, and nickel, and the like can be used.

[0156] As the lithium nickel-cobalt-manganese oxide, for example, lithium nickel-cobalt-manganese oxide having a ratio of nickel:cobalt:manganese = 1:1:1, nickel:cobalt:manganese = 6:2:2, nickel:cobalt:manganese = 8:1:1, nickel:cobalt:manganese = 9:0.5:0.5, etc. Furthermore, as the lithium nickel-cobalt-manganese oxide, it is preferable to use lithium nickel-cobalt-manganese oxide to which one or more of aluminum, calcium, barium, strontium, and gallium have been added.

[0157] As the composite oxide having an olivine structure, any one or more of lithium iron phosphate, lithium manganese phosphate, lithium cobalt phosphate, and lithium iron manganese phosphate can be used. ４ (M2 is one or more elements selected from iron, manganese, and cobalt), but the coefficients of the composition formula are not limited to integers.

[0158] Also, LiMn ２ O ４ A composite oxide having a spinel structure such as the above can be used.

[0159] [Electrolyte] One form of electrolyte can be an electrolytic solution having a solvent and an electrolyte dissolved in the solvent. The electrolytic solution contains a solvent and a lithium salt. The solvent for the electrolytic solution is preferably an aprotic organic solvent, and examples thereof include ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate, chloroethylene carbonate, vinylene carbonate, γ-butyrolactone, γ-valerolactone, dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), methyl formate, methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, 1,3-dioxane, 1,4-dioxane, dimethoxyethane (DME), dimethyl sulfoxide, diethyl ether, methyl diglyme, acetonitrile, benzonitrile, tetrahydrofuran, sulfolane, and sultone, or any combination and ratio of two or more of these.

[0160] When the electrolytic solution contains ethylene carbonate (EC) and diethyl carbonate (DEC), when the total content of ethylene carbonate and diethyl carbonate is 100 vol %, the volume ratio of ethylene carbonate to diethyl carbonate can be x:100-x (where 20≦x≦40). More specifically, a mixed organic solvent containing EC and DEC in a volume ratio of EC:DEC=30:70 can be used.

[0161] Furthermore, when the electrolyte solution contains ethylene carbonate (EC), ethyl methyl carbonate (EMC), and dimethyl carbonate (DMC), when the total content of ethylene carbonate, ethyl methyl carbonate, and dimethyl carbonate is 100 vol%, the volume ratio of ethylene carbonate, ethyl methyl carbonate, and dimethyl carbonate can be x:y:100-x-y (where 5≦x≦35 and 0<y<65). More specifically, a mixed organic solvent containing EC, EMC, and DMC in a volume ratio of EC:EMC:DMC=30:35:35 can be used.

[0162] Furthermore, a mixed organic solvent containing a fluorinated cyclic carbonate (sometimes referred to as a fluorinated cyclic carbonate) or a fluorinated chain carbonate (sometimes referred to as a fluorinated chain carbonate) can be used as the electrolyte. Furthermore, it is preferable that the mixed organic solvent contains both a fluorinated cyclic carbonate and a fluorinated chain carbonate. Both the fluorinated cyclic carbonate and the fluorinated chain carbonate have electron-withdrawing substituents, which are preferable because they lower the solvation energy of lithium ions. Therefore, both the fluorinated cyclic carbonate and the fluorinated chain carbonate are suitable for the electrolyte, and a mixed organic solvent containing these is also suitable.

[0163] Examples of fluorinated cyclic carbonates that can be used include fluoroethylene carbonate (fluoroethylene carbonate, FEC, F1EC), difluoroethylene carbonate (DFEC, F2EC), trifluoroethylene carbonate (F3EC), and tetrafluoroethylene carbonate (F4EC). DFEC has isomers such as cis-4,5 and trans-4,5. Since all fluorinated cyclic carbonates have electron-withdrawing substituents, they are considered to have low solvation energy for lithium ions. The electron-withdrawing substituent in FEC is an F group.

[0164] Methyl 3,3,3-trifluoropropionate is an example of a fluorinated chain carbonate. The abbreviation for methyl 3,3,3-trifluoropropionate is "MTFP." In MTFP, the electron-withdrawing substituent is CF ３ It is the base.

[0165] FEC is a cyclic carbonate with a high dielectric constant, and when used in an organic solvent, it promotes the dissociation of lithium salts. On the other hand, because FEC has electron-withdrawing substituents, it is more likely to desolvate with lithium ions than ethylene carbonate (EC). Specifically, the solvation energy of lithium ions in FEC is lower than that of EC without electron-withdrawing substituents. Therefore, it is easier to separate lithium ions from the surfaces of the positive and negative electrode active materials, thereby reducing the internal resistance of the secondary battery. Furthermore, because FEC has a deep highest occupied molecular orbital (HOMO), it is less susceptible to oxidation and has improved oxidation resistance. On the other hand, there are concerns about the high viscosity of FEC. Therefore, it is recommended to use a mixed organic solvent containing MTFP in addition to FEC alone in the electrolyte. MTFP is a type of chain carbonate, and can have the effect of reducing the viscosity of the electrolyte solution or maintaining the viscosity at room temperature (typically 25° C.) even at low temperatures (typically 0° C.). Furthermore, although MTFP has a lower solvation energy than methyl propionate (abbreviated as "MP"), which does not have an electron-withdrawing substituent, it may form a solvate with lithium ions when used in the electrolyte solution.

[0166] The organic solvent described above is free from granular dust or molecules other than the constituent molecules of the organic solvent (hereinafter simply referred to as "impurities"), and oxygen (O ２ ), water (H ２ 0) or water. ) content is preferably low and highly purified. Furthermore, it is preferable that reaction by-products during synthesis are suppressed through appropriate purification. Specifically, the impurities in the electrolyte are 100 ppm or less, preferably 50 ppm or less, and more preferably less than 10 ppm. The concentration of water among the impurities can be detected by Karl Fischer titration.

[0167] Furthermore, it is preferable that the above-mentioned organic solvent has almost no peaks due to impurities that can be confirmed by NMR measurement or the like. "Almost no peaks can be confirmed" means that the ratio of the integrated area of ​​the peak due to the impurity to the integrated area of ​​the peak due to the main component (simply referred to as "integral ratio") is 0.005 or less, preferably 0.002 or less. The device used for NMR measurement is not particularly limited, but for example, Bruker's "AVANCE III 400" can be used. Furthermore, among the five peaks of acetonitrile derived from acetonitrile-d3 used as a solvent in 1H-NMR measurement, the central peak can be located at 1.94 ppm.

[0168] For example, in the case of MTFP, it is known that when 1H-NMR is measured using acetonitrile-d3 solvent, four peaks appear at δ between 3.29 ppm and 3.43 ppm. However, if other peaks appear in this vicinity, for example, if a peak appears at δ between 3.24 ppm and 3.29 ppm, the peak is considered to be derived from impurities. Therefore, if the ratio (integral ratio) of the peak area between 3.24 ppm and 3.29 ppm to the peak area between 3.29 ppm and 3.43 ppm is 0.005 or less, preferably 0.002 or less, it can be said that peaks due to impurities are almost impossible to confirm.

[0169] The total content of the mixed organic solvent containing FEC and MTFP having such physical properties is taken as 100 vol %, and they are preferably mixed and used in a volume ratio of x:100-x (where 5≦x≦30, preferably 10≦x≦20). In other words, it is preferable to mix them so that there is more MTFP than FEC in the mixed organic solvent.

[0170] Furthermore, by using one or more flame-retardant and non-volatile ionic liquids (room-temperature molten salts) as the solvent for the electrolyte, it is possible to prevent the battery from exploding and / or catching fire even if the internal temperature rises due to an internal short circuit or overcharging of the battery. The ionic liquid is composed of a cation and an anion, and includes an organic cation and an anion. Examples of organic cations used in the electrolyte 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. Examples of anions used in the electrolyte include monovalent amide anions, monovalent methide anions, fluorosulfonate anions, perfluoroalkylsulfonate anions, tetrafluoroborate anions, perfluoroalkylborate anions, hexafluorophosphate anions, and perfluoroalkylphosphate anions.

[0171] [Lithium Salt] Examples of the lithium salt to be dissolved in the solvent include LiPF ６ , LiClO ４ , LiAsF ６ , LiBF ４ , LiAlCl ４ , LiSCN, LiBr, LiI, Li ２ SO ４ , Li ２ B １０ Cl １０ , Li ２ B １２ Cl １２ , LiCF ３ SO ３ , LiC ４ F ９ SO ３ , LiC(CF ３ SO ２ ) ３ , LiC(C ２ F ５ SO ２ ) ３ , LiN(CF ３ SO ２ ) ２ , LiN(C ４ F ９ SO ２ ) (CF ３SO ２ ), LiN(C ２ F ５ SO ２ ) ２ The lithium salt may be used in an amount of 0.5 mol / L or more and 3.0 mol / L or less relative to the solvent. ６ , LiBF ４ The use of these improves the safety of lithium-ion batteries.

[0172] The above-mentioned electrolyte is preferably a highly purified electrolyte with a low content of granular dust or elements other than the constituent elements of the electrolyte (hereinafter simply referred to as "impurities"). Specifically, the weight ratio of impurities to the electrolyte is 1 wt % or less, preferably 0.1 wt % or less, and more preferably 0.01 wt % or less.

[0173] [Additives] The electrolyte may contain additives. The additives can suppress reactive decomposition of the electrolyte that may occur on the positive electrode surface or the negative electrode surface when the battery is operated at high voltage and / or high temperature. Examples of additives that can be used include vinylene carbonate (VC), propane sultone (PS), tert-butylbenzene (TBB), fluoroethylene carbonate (FEC), and lithium bis(oxalate)borate (LiBOB). LiBOB is particularly preferred because it easily forms a good coating. VC or FEC is preferred because it can form a good coating on the negative electrode during battery aging or charging in the early stages of use, improving cycle characteristics.

[0174] The additive may be one or more dinitrile compounds, such as succinonitrile, glutaronitrile, adiponitrile (ADN), or ethylene glycol bis(propionitrile) ether (EGBE).

[0175] Fluorobenzene may also be added to the organic solvent. The concentration of the additive may be, for example, 0.1 wt% or more and 5 wt% or less relative to the total electrolyte solution. PS or EGBE are preferred because they form a good coating on the positive electrode during charge and discharge, improving cycle characteristics. FB is preferred because it improves the wettability of the organic solvent to the positive and negative electrodes. Dinitrile compounds are preferred because their nitrile groups orient to the positive and negative electrodes, inhibiting oxidative decomposition of the organic solvent and improving high-voltage resistance. Furthermore, dinitrile compounds are preferred because they can prevent copper dissolution during overdischarge when a copper-containing current collector is used on the negative electrode. Considering the use of batteries at high voltages, adding a nitrile compound is preferred.

[0176] [Gel Electrolyte] A polymer gel in which a polymer is swollen with an electrolytic solution may be used as the gel electrolyte. By using a polymer gel electrolyte, a semi-solid electrolyte layer can be provided, improving safety against leakage and the like. In addition, it is possible to reduce the thickness and weight of the battery.

[0177] Examples of polymers that can be used to form gels include silicone gel, acrylic gel, acrylonitrile gel, polyethylene oxide gel, polypropylene oxide gel, and fluorine-based polymer gel.

[0178] Examples of polymers that can be used include polymers having a polyalkylene oxide structure such as polyethylene oxide (PEO), PVDF, polyacrylonitrile, and copolymers containing these. For example, PVDF-HFP, which is a copolymer of PVDF and hexafluoropropylene (HFP), can be used. The polymer formed may also have a porous shape.

[0179] [Solid Electrolyte] Instead of an electrolytic solution, a solid electrolyte containing an inorganic material such as a sulfide or oxide, or a solid electrolyte containing a polymer material such as a PEO (polyethylene oxide) can be used. When a solid electrolyte is used, the installation of a separator and / or spacer is unnecessary. Furthermore, since the entire battery can be solidified, there is no risk of leakage, and safety is dramatically improved.

[0180] [Separator] A separator is disposed between the positive electrode and the negative electrode. Examples of separators that can be used include those made of cellulose-containing fibers such as paper, nonwoven fabrics, glass fibers, ceramics, or synthetic fibers such as nylon (polyamide), vinylon (polyvinyl alcohol-based fibers), polyester, acrylic, polyolefin, polyimide, and polyurethane. The separator is preferably processed into a bag shape and disposed so as to encase either the positive electrode or the negative electrode.

[0181] The separator may have a multilayer structure. For example, an organic film such as polypropylene or polyethylene may be coated with a ceramic material, a fluorine-based material, a polyamide material, or a mixture of these. Examples of ceramic materials include aluminum oxide particles and silicon oxide particles. Examples of fluorine-based materials include PVDF and polytetrafluoroethylene. Examples of polyamide materials include nylon and aramid (meta-aramid, para-aramid).

[0182] Coating with ceramic materials improves oxidation resistance, suppressing separator degradation during high-voltage charging and improving the reliability of secondary batteries. Coating with fluorine-based materials also improves adhesion between the separator and electrodes, improving output characteristics. Coating with polyamide materials, especially aramid, improves heat resistance, improving the safety of secondary batteries.

[0183] For example, both sides of a polypropylene film may be coated with a mixed material of aluminum oxide and aramid, or the surface of the polypropylene film that contacts the positive electrode may be coated with a mixed material of aluminum oxide and aramid, and the surface that contacts the negative electrode may be coated with a fluorine-based material.

[0184] When a separator with a multilayer structure is used, the safety of the secondary battery can be maintained even if the overall thickness of the separator is thin, and therefore the capacity per volume of the secondary battery can be increased.

[0185] [Exterior Body] The exterior body of the battery can be made of a metal material such as aluminum, stainless steel, or titanium, or a resin material. A film-like exterior body can also be used. Examples of films that can be used include a three-layer structure in which a highly flexible metal thin film or metal foil such as aluminum, stainless steel, titanium, copper, or nickel is provided on a film made of a material such as polyethylene, polypropylene, polycarbonate, ionomer, or polyamide, and an insulating synthetic resin film such as a polyamide resin or polyester resin is further provided on the metal thin film as the outer surface of the exterior body. Such a multilayer structure film can be called a laminate film. In this case, the laminate film may be referred to as an aluminum (aluminum) laminate film, a stainless steel laminate film, a titanium laminate film, a copper laminate film, a nickel laminate film, or the like, using the name of the material of the metal layer.

[0186] The material or thickness of the metal layer of the laminate film may affect the flexibility of the battery. For example, an aluminum laminate film having a polypropylene layer, an aluminum layer, and nylon is preferably used as an exterior body for a battery with excellent flexibility (flexibility). Here, the thickness of the aluminum layer is preferably 50 μm or less, more preferably 40 μm or less, more preferably 30 μm or less, and more preferably 20 μm or less. If the aluminum layer is thinner than 10 μm, there is a concern that pinholes in the aluminum layer may reduce the gas barrier properties, so the thickness of the aluminum layer is preferably 10 μm or more.

[0187] Alternatively, a graphene sheet may be used as the laminate film instead of the metal layer. The graphene sheet may be a multilayer graphene sheet having a thickness of 100 nm to 30 μm, preferably 200 nm to 20 μm. The graphene sheet is flexible, has an interlayer distance of 0.34 nm, and has gas barrier properties, making it suitable for use as an exterior body for a secondary battery.

[0188] [Method for Processing a Film Having Concave and Convex Portions] Next, a method for processing a film that can be used for an exterior body will be described. The above-mentioned laminate film can be used as the film.

[0189] For example, a laminate film can be used as the laminate film. For example, a laminate film having a heat seal layer on one or both surfaces of a metal film can be used as the laminate film. For the adhesive layer, a heat-sealable resin film containing polypropylene, polyethylene, or the like can be used. In this embodiment, an aluminum laminate film is used which has a nylon resin on the surface of an aluminum foil and an acid-resistant polypropylene film and a polypropylene film laminate on the back surface of the aluminum foil.

[0190] The film is then embossed, resulting in a film with a concave-convex pattern. The film has a plurality of concave-convex portions, giving it a visible wavy pattern.

[0191] Embossing, which is a type of press working, will be explained below.

[0192] Fig. 16 is a cross-sectional view showing an example of embossing. Embossing is a type of press processing, and refers to a process in which an embossing roll with an uneven surface is pressed against a film to form unevenness in the film corresponding to the unevenness of the embossing roll. The embossing roll is a roll with a pattern engraved on its surface.

[0193] 16 shows an example of embossing on both sides of a film, and a method of forming a film with convex portions having peaks on one side.

[0194] 16 shows a state in which a film 190 is sandwiched between an embossing roll 195 in contact with one side of the film and an embossing roll 196 in contact with the other side, and the film 190 is being fed in a film traveling direction 191. A pattern is formed on the film surface by pressure or heat. Alternatively, a pattern may be formed on the film surface by both pressure and heat.

[0195] As the embossing roll, a metal roll, a ceramic roll, a plastic roll, a rubber roll, an organic resin roll, a wooden roll, or the like can be used as appropriate.

[0196] In Figure 16, embossing is performed using an embossing roll 196, which is a male-patterned embossing roll, and a female-patterned embossing roll 195. The male-patterned embossing roll 196 has multiple convex portions 196a. The convex portions 196a correspond to the convex portions to be formed on the film to be processed. The female-patterned embossing roll 195 has multiple convex portions 195a. Adjacent convex portions 195a form recesses that fit into the convex portions to be formed on the film by the convex portions 196a provided on the male-patterned embossing roll 196.

[0197] Convex portions and flat portions can be formed continuously by successively performing embossing to raise a portion of film 190 and blank pressing to depression a portion of film 190. As a result, a pattern can be formed on film 190.

[0198] Next, a film having a plurality of convex portions with shapes different from those shown in Fig. 16 will be described with reference to Fig. 17A to Fig. 17E. By changing the convex shapes of embossing roll 195 and embossing roll 196 shown in Fig. 16 to shapes different from those shown in Fig. 16, embossing with various cross-sectional shapes shown in Fig. 17A to Fig. 17E can be performed.

[0199] Fig. 17A is a cross-sectional schematic diagram of an embossment having a wavy shape, and Figs. 17B to 17E are modified examples of Fig. 17A. Figs. 17B and 17C are diagrams showing an example in which the wavy shape is formed in a stepped shape, Fig. 17D is a diagram showing an example in which the wavy shape is formed in a rectangular shape, and Fig. 17E is a diagram showing an example in which the wavy shape is formed with acute-angled valley shapes and trapezoidal peak shapes.

[0200] FIG. 18A is a bird's-eye view showing an exterior body 150a resulting from the embossing process shown in FIGS. 16 to 17E performed twice with the film 190 rotated in different directions, and an exterior body 150b without the embossing process. Specifically, the film 190 is embossed in a first direction, and then embossed in a second direction rotated 90 degrees from the first direction, thereby obtaining the exterior body 150a having the embossed shape (which can be referred to as a cross-wave shape) shown in FIG. 18A. The exterior body 150a and the exterior body 150b can be used to fabricate the battery module 100y described in FIG. 10C. The exterior body 150a with the cross-wave shape and the flat exterior body 150b shown in FIG. 18A can also be formed as a single exterior body 150c, as shown in FIG. 18B, and folded in half for use in fabricating the battery module.

[0201] The content of this embodiment can be freely combined with the content of other embodiment modes.

[0202] Embodiment 2 In this embodiment, a structural example of an electronic device including a battery module according to one embodiment of the present invention will be described.

[0203] The electronic device 10 of one embodiment of the present invention will be described with reference to FIGS. 19A to 24B.

[0204] 19A to 19C are schematic diagrams illustrating the electronic device 10. Fig. 19A is a top view of the electronic device 10. Fig. 19B is a cross-sectional view showing the cross-sectional structure taken along dashed dotted line A1-A2 in Fig. 19A. Fig. 19C is a perspective view of the electronic device 10 in a bent state.

[0205] The electronic device 10 includes a display unit 11 , a battery unit 100 , a control circuit unit 300 , and a flexible substrate unit 200 .

[0206] 19B shows an example in which electronic device 10 has a plurality of battery units 100 (battery unit 100A, battery unit 100B, battery unit 100C, battery unit 100D, battery unit 100E, battery unit 100F, battery unit 100G, and battery unit 100H). Also, as shown in FIG. 19B , electronic device 10 has a plurality of control circuit units 300 (control circuit unit 300A, control circuit unit 300B, control circuit unit 300C, control circuit unit 300D, control circuit unit 300E, control circuit unit 300F, control circuit unit 300G, and control circuit unit 300H).

[0207] 19B, the plurality of battery modules 100 are connected to one surface of the flexible substrate module 200. The plurality of control circuit modules 300 are connected to the other surface of the flexible substrate module 200. In this manner, the battery modules 100, the control circuit modules 300, and the flexible substrate module 200 are integrated together, and can be called an integrated substrate. The battery modules 100 and the flexible substrate module 200 can have the same configuration as the battery module described in the first embodiment.

[0208] Specifically, as shown in FIG. 19B, the electronic device 10 can use a battery module 20A having a battery unit 100A and a flexible substrate unit 200, the electronic device 10 can use a battery module 20B having a battery unit 100B and a flexible substrate unit 200, the electronic device 10 can use a battery module 20C having a battery unit 100C and a flexible substrate unit 200, the electronic device 10 can use a battery module 20D having a battery unit 100D and a flexible substrate unit 200, the electronic device 10 can use a battery module 20E having a battery unit 100E and a flexible substrate unit 200, the electronic device 10 can use a battery module 20F having a battery unit 100F and a flexible substrate unit 200, the electronic device 10 can use a battery module 20G having a battery unit 100G and a flexible substrate unit 200, and the electronic device 10 can use a battery module 20H having a battery unit 100H and a flexible substrate unit 200.

[0209] It should be noted that battery module 20A, battery module 20B, battery module 20C, battery module 20D, battery module 20E, battery module 20F, battery module 20G, and battery module 20H can be collectively referred to as battery module 20. For example, the configuration of electronic device 10 shown in Fig. 19B can be said to be a configuration having control circuit unit 300 on battery module 20, and having display unit 11 on the control circuit unit.

[0210] [Configuration example of integrated substrate] Fig. 20A is a cross-sectional view of the electronic device 10 having the shape shown in Fig. 19C taken along the line A1-A2. Fig. 20B is a cross-sectional view of the integrated substrate 30 in Fig. 20A. Fig. 20C is a perspective view of the integrated substrate 30 viewed from the same angle as Fig. 19C.

[0211] 20A to 20C, the integrated substrate 30 housed inside the electronic device 10 deforms (bends) as the electronic device 10 deforms. As shown in Fig. 20B, the integrated substrate 30 deforms at a position (the position indicated by the arrow in the figure) of the flexible substrate unit 200 that is not in contact with the control circuit unit 300.

[0212] Fig. 21A is a schematic cross-sectional view of the integrated substrate 30 in an undeformed (unbent) state, and Fig. 21B is a perspective view showing the layered relationship of the battery unit 100, the control circuit unit 300, and the flexible substrate unit 200 of the integrated substrate 30.

[0213] 21B , the flexible substrate unit 200 has a first region 14 a and a second region 14 b (also referred to as a flexible region 220). The second region 14 b has higher flexibility than the first region 14 a. In other words, when an external force is applied to the flexible substrate unit 200, the second region 14 b is more likely to deform.

[0214] 21B , the plurality of control circuit units 300 are connected to one surface of the flexible substrate unit 200. In addition, the plurality of battery units 100 are connected to the flexible substrate unit 200 via the plurality of control circuit units 300.

[0215] Specifically, battery unit 100A is connected to first region 14a of flexible substrate unit 200 via control circuit unit 300A. Battery unit 100B is connected to first region 14a of flexible substrate unit 200 via control circuit unit 300B. Battery unit 100C is connected to first region 14a of flexible substrate unit 200 via control circuit unit 300C. Battery unit 100D is connected to first region 14a of flexible substrate unit 200 via control circuit unit 300D. Battery unit 100E is connected to first region 14a of flexible substrate unit 200 via control circuit unit 300E. Battery unit 100F is connected to first region 14a of flexible substrate unit 200 via control circuit unit 300F. The battery unit 100G is connected to the first region 14a of the flexible substrate unit 200 via the control circuit unit 300G. The battery unit 100H is connected to the first region 14a of the flexible substrate unit 200 via the control circuit unit 300H.

[0216] An example of the configuration of the control circuit section 300 will be described with reference to FIG.

[0217] [Control Circuit Unit] Fig. 22 is a perspective view illustrating the inside of the control circuit unit 300. As shown in Fig. 22, a plurality of IC chips 16 are provided inside the control circuit unit 300 on the flexible substrate unit 200. Furthermore, passive elements such as resistors, capacitors, and coils can be provided inside the control circuit unit 300.

[0218] The IC chip 16, passive elements, etc. are not only electrically connected by wiring inside the control circuit unit 300, but can also be electrically connected to another control circuit unit 300 by a wiring layer inside the flexible substrate unit 200. For example, an IC chip inside the control circuit unit 300A and an IC chip inside the control circuit unit 300B can be electrically connected by a wiring layer inside the flexible substrate unit 200. In other words, the multiple control circuit units 300 (control circuit unit 300A, control circuit unit 300B, control circuit unit 300C, control circuit unit 300D, control circuit unit 300E, control circuit unit 300F, control circuit unit 300G, and control circuit unit 300H) can be electrically connected to each other by a wiring layer inside the flexible substrate unit 200.

[0219] The number of control circuit units 300 described above is an example for the purpose of explanation, and the number of control circuit units 300 included in the integrated substrate 30 is not limited to the above number. For example, the integrated substrate 30 may be configured to have two control circuit units 300, or three or more control circuit units 300.

[0220] The battery section 100 can be provided over the entire control circuit section 300, but the battery section 100 may not be provided in a position overlapping an IC chip that generates a large amount of heat, such as a CPU.

[0221] 23A to 23C are block diagrams of structural examples of electronic devices including a battery module of one embodiment of the present invention. The positional relationship in each of the block diagrams is taken into consideration, and the positional relationship corresponds to that of the cross-sectional view of FIG. 19B .

[0222] FIG. 23A is a block diagram of an electronic device 10 having a display unit 11, a battery unit 100, a control circuit unit 300, and a flexible substrate unit 200.

[0223] Battery unit 100 includes battery unit 100A, battery unit 100B, battery unit 100C, battery unit 100D, battery unit 100E, battery unit 100F, battery unit 100G, and battery unit 100H, and Fig. 23A illustrates battery unit 100A, battery unit 100B, and battery unit 100H. Control circuit unit 300 includes control circuit unit 300A, control circuit unit 300B, control circuit unit 300C, control circuit unit 300D, control circuit unit 300E, control circuit unit 300F, control circuit unit 300G, and control circuit unit 300H, and Fig. 23A illustrates control circuit unit 300A, control circuit unit 300B, and control circuit unit 300H.

[0224] 23A shows an example of the configuration of electronic device 10, in which control circuit unit 300A has battery control IC 16A, control circuit unit 300B has CPU 16B, and control circuit unit 300H has driver IC 16H. Note that driver IC 16H has a driver circuit for outputting video to display unit 11.

[0225] 23A , the battery module 100A is connected to the battery control IC 16A included in the control circuit module 300A via the flexible substrate module 200. The battery module 100B is connected to the battery control IC 16A included in the control circuit module 300A via the control circuit module 300B and the flexible substrate module 200. Similarly, the battery module 100H is connected to the battery control IC 16A included in the control circuit module 300A via the control circuit module 300H and the flexible substrate module 200.

[0226] 23B and 23C are block diagrams illustrating a configuration in which a plurality of battery modules 100 (battery modules 100A to 100H) are connected via a flexible substrate module 200. FIG.

[0227] As shown in Fig. 23B, the battery modules 100A to 100H can be connected in series via the wiring layer of the flexible substrate unit 200. Alternatively, as shown in Fig. 23C, the battery modules 100A to 100H can be connected in parallel via the wiring layer of the flexible substrate unit 200. Alternatively, although not shown, the battery modules 100A to 100H can be connected in any combination of series and parallel via the wiring layer of the flexible substrate unit 200.

[0228] Figures 24A and 24B are circuit diagrams corresponding to the block diagrams shown in Figures 23A and 23C. In Figures 24A and 24B, electrical connections of the power supply system are shown by solid lines, and electrical connections of the signal system are shown by dashed dotted lines. Figures 24A and 24B are electrically connected at connection terminal M+ and connection terminal M-.

[0229] The configuration example shown in FIG. 24A includes a current sensor 18A, a voltage sensor 18B, a switch 19A, and a switch 19B in addition to the configuration described in FIG. 23A.

[0230] 24A, current sensor 18A, voltage sensor 18B, switch 19A, and switch 19B are each connected to battery control IC 16A. The VCC terminal of battery control IC 16A is connected to the power supply system on the positive side of battery module 100, and the GND terminal is connected to the power supply system on the negative side of battery module 100.

[0231] The configuration example shown in FIG. 24B includes, in addition to the configuration described in FIG. 23A, a memory 16C, a DCDC converter 16D, a charging control IC 16E, a wireless charging power receiving unit 21A, and a wired charging power receiving unit 21B.

[0232] 24B , DCDC converter 16D has a function of converting the voltage of direct current supplied from battery module 100 and supplying the converted voltage to display module 11, drive IC 16H, CPU 16B, and memory 16C. Charging control IC 16E is connected to wireless charging power receiving module 21A and wired charging power receiving module 21B. Charging control IC 16E has a function of supplying power supplied from wireless charging power receiving module 21A or wired charging power receiving module 21B to battery module 100.

[0233] The display unit 11 may include a liquid crystal display (LCD), an electroluminescence (EL), or a light emitting diode (LED) as a display device. The display device may include a quantum dot (Q-Dot).

[0234] In this embodiment, EL includes organic EL and inorganic EL. In this embodiment, LED includes micro LED, mini LED, and macro LED. In this specification, etc., when the chip area is 10000 μm ２ The following light-emitting diodes are called micro LEDs, and the chip area is 10,000 μm ２ Larger than 1mm ２ The following light-emitting diodes are called mini LEDs, with a chip area of ​​1 mm ２ Larger light emitting diodes are sometimes referred to as macro LEDs.

[0235] The structure, method, and the like described in this embodiment can be used in appropriate combination with the structure, method, and the like described in other embodiments.

[0236] 10: Electronic device, 11: Display unit, 14a: First region, 14b: Second region, 16: IC chip, 18A: Current sensor, 18B: Voltage sensor, 19A: Switch, 19B: Switch, 20: Battery module, 21A: Wireless charging power receiving unit, 21B: Wired charging power receiving unit, 30: Integrated substrate, 51: Opening, 52: Opening, 61: Tab portion, 62: Tab portion, 100: Battery unit, 110: Laminated unit, 120: Positive electrode, 121: Positive electrode current collector, 122: Positive electrode active material layer, 130: Negative electrode, 131: Negative electrode current collector, 132: Negative electrode active material layer, 140: Separator, 150: Exterior body, 151: Resin layer, 152: Metal layer, 153: Resin layer, 154a: Sealing portion, 154b: Sealing portion , 154c: sealing portion, 155: opening, 155a: adhesive portion, 156: opening, 156a: adhesive portion, 160: positive electrode terminal, 161: metal layer, 162: connection portion, 163: resin layer, 170: negative electrode terminal, 171: metal layer, 172: connection portion, 173: resin layer, 180: plane, 181: plane, 190: film, 191: traveling direction, 195: embossing roll, 195a: convex portion, 196: embossing roll, 196a: convex portion, 200: flexible substrate portion, 201: resin layer, 202: metal layer, 203: resin layer, 204: metal layer, 205: resin layer, 210: adhesive layer, 211: opening, 212: opening, 220: region, 251: opening, 252: opening, 300: control circuit portion,

Claims

A flexible substrate and a battery provided on the flexible substrate, the flexible substrate has a metal layer; the battery has an exterior body, and electrodes and connection terminals provided in a space surrounded by the exterior body; the electrode is connected to the connection terminal, the connection terminal is connected to the metal layer through an opening provided in the exterior body at a position overlapping the flexible substrate; Battery module. 　 In claim 1, the flexible substrate has a first resin layer and a second resin layer; The metal layer is located between the first resin layer and the second resin layer. Battery module. 　 In claim 1, the connection terminal has a resin layer, the resin layer is provided around the opening and is adhered to the exterior body; Battery module. 　 a flexible substrate; an exterior body connected to the flexible substrate; and a positive electrode and a positive electrode terminal provided in a space surrounded by the exterior body; the flexible substrate has a first resin layer, a second resin layer, and a first metal layer located between the first resin layer and the second resin layer; the exterior body includes a third resin layer, a fourth resin layer, and a second metal layer located between the third resin layer and the fourth resin layer, the positive electrode has a positive electrode current collector, the positive electrode terminal has a fifth resin layer and a third metal layer, one surface of the third metal layer is connected to the positive electrode current collector; the second resin layer has a region connected to the third resin layer, the other surface of the third metal layer has a region connected to the fourth resin layer via the fifth resin layer; the fifth resin layer, the fourth resin layer, the second metal layer, the third resin layer, and the second resin layer each have a first opening extending from the first metal layer to the third metal layer; In the first opening, the first metal layer and the third metal layer are connected by a first conductive resin. Battery module. 　 a flexible substrate; an exterior body connected to the flexible substrate; and a positive electrode, a negative electrode, a positive electrode terminal, and a negative electrode terminal provided in a space surrounded by the exterior body; the flexible substrate has a first resin layer, a second resin layer, a third resin layer, a first metal layer located between the first resin layer and the second resin layer, and a second metal layer located between the second resin layer and the third resin layer; the exterior body includes a fourth resin layer, a fifth resin layer, and a third metal layer located between the fourth resin layer and the fifth resin layer, the positive electrode has a positive electrode current collector, the negative electrode has a negative electrode current collector, the positive electrode terminal has a sixth resin layer and a fourth metal layer, the negative electrode terminal has a seventh resin layer and a fifth metal layer, one surface of the fourth metal layer is connected to the positive electrode current collector; one surface of the fifth metal layer is connected to the negative electrode current collector; the third resin layer has a region connected to the fourth resin layer, the other surface of the fourth metal layer has a region connected to the fifth resin layer via the sixth resin layer; the sixth resin layer, the fifth resin layer, the third metal layer, the fourth resin layer, and the third resin layer have a first opening extending from the second metal layer to the fourth metal layer; In the first opening, the second metal layer and the fourth metal layer are connected by a first conductive resin; the other surface of the fifth metal layer has a region connected to the fifth resin layer via the seventh resin layer; the seventh resin layer, the fifth resin layer, the third metal layer, the fourth resin layer, the third resin layer, the second metal layer, and the second resin layer have a second opening extending from the first metal layer to the fifth metal layer; In the second opening, the first metal layer and the fifth metal layer are connected by a second conductive resin. Battery module. 　 A battery module according to claim 5 is provided. A control circuit unit is provided on the battery module, A display unit is provided on the control circuit unit. electronic equipment.

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