Electrode lead, electric device, exterior body, and manufacturing method for electric device

Abstract

To support reliability improvement in an electric device.SOLUTION: An electrode lead 10 which connects interior and exterior of an exterior body in a first direction includes: a metal lead 11; a first layer 13 which covers the metal lead 11 in a first direction around an axis; a second layer 14 which has a lower melting point than the first layer 13 and covers at least a part of the first layer 13 in the first direction around the axis. The first layer 13 contacts the metal lead 11, and the second layer 14 contacts the exterior body.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] The present disclosure relates to an electrode lead, an electric device, an exterior body, and a method for manufacturing an electric device. [Background technology]

[0002] Patent Document 1 discloses a sealing film for sealing the electrodes of a power generating element. In the sealing film, an inner laminate and an outer laminate are laminated together via a connecting layer made of a low-melting-point resin. Patent Document 1 describes that the connecting layer melts during thermocompression bonding with the electrodes, resulting in excellent sealing of the electrodes.

[0003] Patent Document 2 discloses a thin battery comprising an exterior film material, an electrode group housed within the exterior film material, and an external lead extending from the exterior film material. The electrode group is sealed by sandwiching insulating resin films on both sides of the external lead and heat sealing them. The insulating resin film disclosed in Patent Document 2 has a multilayer structure including a first resin film that contacts the external lead and a second resin film that does not contact the external lead, and the second resin film has a higher melting point than the first resin film. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-224218 [Patent Document 2] Japanese Patent Application Laid-Open No. 2002-245988 Summary of the Invention [Problem to be solved by the invention]

[0005] There is room for improvement in the above-described conventional techniques in terms of improving the reliability of electrical devices.

[0006] Therefore, the present disclosure provides an electrode lead and an exterior body that can help improve the reliability of an electrical device, as well as an electrical device that can improve reliability and a method for manufacturing the same. [Means for solving the problem]

[0007] An electrode lead according to one embodiment of the present disclosure is an electrode lead that connects the inside and outside of an outer casing in a first direction, and includes a metal lead, a first layer that covers the metal lead around an axis in the first direction, and a second layer that has a lower melting point than the first layer and covers at least a portion of the first layer around the axis in the first direction, wherein the first layer contacts the metal lead and the second layer contacts the outer casing.

[0008] An electric device according to one aspect of the present disclosure includes the electrode lead according to one aspect of the present disclosure and the exterior body.

[0009] An electrode lead according to one embodiment of the present disclosure comprises a metal lead, a first layer covering the metal lead around an axis in a first direction, and a second layer having a lower melting point than the first layer and covering at least a portion of the first layer around the axis in the first direction, wherein the metal lead is slidable in the first direction relative to the first layer.

[0010] An exterior body according to one embodiment of the present disclosure includes one or more films to which the second layers of two electrode leads, each of which is an electrode lead according to one embodiment of the present disclosure, are bonded.

[0011] A method for manufacturing an electrical device according to one embodiment of the present disclosure includes a first step of heat-sealing a member covering a metal lead to an outer casing around an axis in a first direction, and a second step of heat-sealing the member to the metal lead after the first step. [Effects of the Invention]

[0012] According to the present disclosure, it is possible to help improve the reliability of electrical devices. [Brief explanation of the drawings]

[0013] [Figure 1A] FIG. 1A is a plan view of an electrode lead according to a first embodiment. [Figure 1B] FIG. 1B is a front view of the electrode lead according to the first embodiment. [Figure 1C] FIG. 1C is a side view of the electrode lead according to the first embodiment. [Figure 2A] FIG. 2A is a plan view of an exterior body to which an electrode lead according to embodiment 1 is joined. [Figure 2B] FIG. 2B is a cross-sectional view of the exterior body taken along line IIB-IIB in FIG. 2A. [Figure 3A] FIG. 3A is a plan view of an exterior body for illustrating that a part of the electrode lead according to the first embodiment is slidable. [Figure 3B] FIG. 3B is a cross-sectional view of the exterior body taken along line IIIB-IIIB in FIG. 3A. [Figure 4A] FIG. 4A is a plan view of a battery according to embodiment 2. FIG. [Figure 4B] FIG. 4B is a cross-sectional view of the battery taken along line IVB-IVB in FIG. 4A. [Figure 4C] FIG. 4C is a cross-sectional view of the battery taken along line IVC-IVC in FIG. 4A. [Figure 5A] FIG. 5A is a plan view of a power generating element included in a battery according to Embodiment 2. FIG. [Figure 5B] FIG. 5B is a cross-sectional view of the power generating element taken along line VB-VB in FIG. 5A. [Figure 5C] FIG. 5C is a cross-sectional view of the power generating element taken along line VC-VC in FIG. 5A. [Figure 6A] FIG. 6A is a cross-sectional view of another example of a power generating element included in the battery according to Embodiment 2. FIG. [Figure 6B] FIG. 6B is another cross-sectional view of the power generating element shown in FIG. 6A. [Figure 6C] FIG. 6C is a cross-sectional view of another example of a power generating element included in the battery according to embodiment 2. As shown in FIG. [Figure 6D] FIG. 6D is another cross-sectional view of the power generating element shown in FIG. 6C. [Figure 7] FIG. 7 is a flowchart showing a method for manufacturing a battery according to each embodiment and each modification. [Figure 8A] FIG. 8A is a plan view of an exterior body for illustrating that a part of an electrode lead and a power generating element according to embodiment 2 are slidable. [Figure 8B] FIG. 8B is a plan view of an exterior body for illustrating that a part of the electrode lead and the power generating element according to the second embodiment are slidable. [Figure 9A] FIG. 9A is a plan view illustrating one step of the method for manufacturing the battery according to Embodiment 2. FIG. [Figure 9B] FIG. 9B is a plan view for explaining a step performed after the step shown in FIG. 9A. [Figure 9C] FIG. 9C is a plan view for explaining a step performed after the step shown in FIG. 9B. [Figure 9D] FIG. 9D is a plan view for explaining a step performed after the step shown in FIG. 9C. [Figure 9E] FIG. 9E is a plan view for explaining a step performed after the step shown in FIG. 9D. [Figure 10A] FIG. 10A is a plan view of an exterior package according to the third embodiment. [Figure 10B] FIG. 10B is a cross-sectional view of the exterior body taken along line XB-XB in FIG. 10A. [Figure 11A] FIG. 11A is a plan view of an exterior package according to a first modification of the third embodiment. [Figure 11B] FIG. 11B is a cross-sectional view of the exterior body taken along line XIB-XIB in FIG. 11A. [Figure 11C] FIG. 11C is a plan view illustrating one step in a method for manufacturing a battery using the exterior package shown in FIG. 11A. [Figure 11D] FIG. 11D is a plan view for explaining a step performed after the step shown in FIG. 11C. [Figure 11E] FIG. 11E is a cross-sectional view of the battery taken along line XIE-XIE in FIG. 11D. [Figure 11F]FIG. 11F is a cross-sectional view of the battery taken along line XIF-XIF in FIG. 11D. [Figure 12A] FIG. 12A is a plan view of an exterior package according to Variation 2 of Embodiment 3. FIG. [Figure 12B] 12B is a cross-sectional view of the exterior body taken along line XIIB-XIIB in FIG. 12A. [Figure 12C] FIG. 12C is a plan view of a power generating element according to Modification 2 of Embodiment 3. FIG. [Figure 12D] FIG. 12D is a plan view illustrating a step of the method for manufacturing a battery according to Modification 2 of Embodiment 3. As shown in FIG. [Figure 13A] FIG. 13A is a cross-sectional view showing an example of a battery cell included in a power generating element according to each embodiment and each modification. [Figure 13B] FIG. 13B is a cross-sectional view showing another example of a battery cell included in the power generating element according to each of the embodiments and modifications. [Figure 13C] FIG. 13C is a cross-sectional view showing another example of a battery cell included in a power generating element according to each of the embodiments and modifications. DETAILED DESCRIPTION OF THE INVENTION

[0014] (Summary of the Disclosure) The electrical device includes a device placed in the internal space of an exterior body. The internal space is sealed to protect the device. The sealing portion for sealing the internal space is formed by joining the overlapping portions of one or more films that make up the exterior body by heat fusion or the like.

[0015] The electrode lead according to the present disclosure can be used for electrical connection to a device and is arranged so as to communicate between the inside and outside of an exterior body. The electrode lead is sandwiched between overlapping portions of one or more films and sealed by heat sealing the films.

[0016] However, heat sealing carries the risk of thermal load on the device. When forming the heat-sealed portion of the film that sandwiches the electrode lead (hereinafter referred to as the electrode sealing portion), the entire side of the film, including the electrode sealing portion, is usually fused and sealed. This means that a large thermal load is transmitted to the device through the metal lead. This transmitted heat risks causing deterioration and damage to the device, which could impair its reliability.

[0017] Heat sealing also poses mechanical risks. Before forming the electrode sealing portion, the relative positions of the electrode lead and the film are not determined. This makes it easy for the electrode lead to become misaligned. In a sealing process that allows for misalignment, it is necessary to ensure the safety of the relative positions of the sealing equipment that performs the heat sealing and the device and / or film.

[0018] Thus, conventional electrical devices are required to have improved reliability. Therefore, the present disclosure provides an electrode lead and the like that can help improve the reliability of electrical devices.

[0019] The electrode lead according to a first aspect of the present disclosure is an electrode lead that connects the inside and outside of an outer casing in a first direction, and includes a metal lead, a first layer that covers the metal lead around an axis in the first direction, and a second layer that has a lower melting point than the first layer and covers at least a portion of the first layer around the axis in the first direction, wherein the first layer contacts the metal lead and the second layer contacts the outer casing.

[0020] This can help improve the reliability of the electrical device. Specifically, the electrode lead according to this embodiment includes a second layer having a lower melting point than the first layer, enabling two-stage heat fusion. More specifically, the first stage of heat fusion heat-bonds the film to the second layer, and the second stage of heat fusion heat-bonds the metal lead to the first layer. Because the melting point of the second layer is lower than that of the first layer, the first stage of heat fusion can melt the second layer without melting the first layer, thereby heat-fusing the film to the second layer. This allows the relative positional relationship between the film and the first and second layers of the electrode lead to be determined.

[0021] From the start of the first-stage heat fusion, the first layer and the metal lead can be kept unfused even at the end of the first-stage heat fusion. In other words, the metal lead and the device connected to the metal lead can slide relative to the first and second layers. This allows the first-stage heat fusion to be performed with a long distance between the electrode sealing portion and the device, thereby suppressing device degradation due to heat. It also reduces the risk of the device being accidentally pinched in the heating head of the sealing equipment and damaged, thereby improving process safety.

[0022] Furthermore, since the second-stage heat fusion only requires heat fusion between the metal lead and the second layer, the amount of heat and the heating area can be narrowed. This also helps prevent device degradation due to the heat of the second-stage heat fusion. The heating head can also be made smaller, which reduces the risk of device damage due to pinching by the heating head. Furthermore, during the second-stage heat fusion, movement of the device in any direction other than the sliding direction is restricted, making it less likely for the device to shift position and reducing the risk of device damage.

[0023] In this way, the electrode lead according to this aspect can help improve the area efficiency and reliability of the electrical device.

[0024] After the first heat fusion step, the metal lead may be slid to bring the device and the electrode sealing portion closer together. This reduces the excess space. The excess space is the space within the exterior body that exists between the electrode sealing portion and the device.

[0025] In an electrical device, both the electrode sealing portion and the excess space are portions that do not perform the device's original function. Therefore, by reducing the electrode sealing portion and the excess space, the area efficiency of the electrical device can be increased. In this specification, the area efficiency is expressed as the ratio of the power generating element to the projected area of the electrical device. The projection direction in this case is a direction perpendicular to the main surface of the electrical device.

[0026] An electrode lead according to a second aspect of the present disclosure is the electrode lead according to the first aspect, wherein the first layer is longer than the second layer in the first direction.

[0027] This makes it difficult for the second layer, which melts during the first heat-sealing step, to come into contact with the metal lead even if it flows. This prevents the metal lead and the second layer from being fixed together at the end of the first heat-sealing step, making it easier to maintain the metal lead in a state where it can slide relative to the first and second layers. This reduces excess space, helping to improve area efficiency.

[0028] An electrode lead according to a third aspect of the present disclosure is the electrode lead according to the second aspect, wherein the length of the first layer is 1.2 times or more the length of the second layer.

[0029] This makes it easier to maintain the metal leads in a state where they can slide relative to the first and second layers at the end of the first heat fusion step, thereby reducing excess space and helping to improve area efficiency.

[0030] An electrode lead according to a fourth aspect of the present disclosure is the electrode lead according to any one of the first to third aspects, wherein the melting point of the first layer is higher than the melting point of the second layer by 20° C. or more.

[0031] This increases the difference in melting points between the first and second layers, making it difficult for the first layer to melt during the first heat-sealing stage. This prevents the metal lead from being fixed to the first layer at the end of the first heat-sealing stage, making it easier to maintain the metal lead in a slidable state relative to the first layer. This reduces excess space, helping to improve area efficiency.

[0032] An electrode lead according to a fifth aspect of the present disclosure is the electrode lead according to any one of the first to fourth aspects, wherein the first layer is thicker than the second layer.

[0033] This strengthens the fusion bond to the first layer metal lead, improving the sealing performance of the electrode sealing portion, which makes it more difficult for foreign matter such as water to enter the internal space of the exterior body through the electrode sealing portion, thereby improving the reliability of the device.

[0034] An electrode lead according to a sixth aspect of the present disclosure is the electrode lead according to the fifth aspect, wherein the thickness of the first layer is 1.5 times or more the thickness of the second layer.

[0035] This strengthens the fusion bond to the first layer metal lead, improving the sealing performance of the electrode sealing portion, which makes it more difficult for foreign matter such as water to enter the internal space of the exterior body through the electrode sealing portion, thereby improving the reliability of the device.

[0036] An electric device according to a seventh aspect of the present disclosure includes the electrode lead according to any one of the first to sixth aspects and the exterior body.

[0037] This makes it possible to realize an electric device with improved reliability, and also to improve the area efficiency of the electric device.

[0038] An electrode lead according to an eighth aspect of the present disclosure comprises a metal lead, a first layer covering the metal lead around an axis in a first direction, and a second layer having a lower melting point than the first layer and covering at least a portion of the first layer around the axis in the first direction, wherein the metal lead is slidable in the first direction relative to the first layer.

[0039] This can help improve the reliability of the electrical device, as with the electrode lead according to the first aspect described above, and can also help improve the area efficiency of the electrical device.

[0040] An exterior body according to a ninth aspect of the present disclosure includes one or more films to which the second layers of two electrode leads, each of which is the electrode lead according to the eighth aspect, are bonded.

[0041] This helps improve the area efficiency and reliability of the electrical device.Because the exterior body and the second layer can be thermally fused before the device is fixed to the metal leads, device degradation due to heat can be suppressed.

[0042] An exterior package according to a tenth aspect of the present disclosure is the exterior package according to the ninth aspect, wherein the two electrode leads are arranged in parallel.

[0043] This allows the two metal leads to slide in the same direction, making it easier for the device to slide, reducing damage to the device when sliding and improving reliability.

[0044] A method for manufacturing an electrical device according to an eleventh aspect of the present disclosure includes a first step of heat-sealing a member covering a metal lead to an outer casing around an axis in a first direction, and a second step of heat-sealing the member to the metal lead after the first step.

[0045] This allows the thermal fusion to be performed in two stages, making it possible to manufacture an electric device with improved reliability and also to improve the area efficiency of the electric device.

[0046] A method for producing an electric device according to a twelfth aspect of the present disclosure is the method for producing an electric device according to the eleventh aspect, wherein the heating range in the second step is narrower than the heating range in the first step.

[0047] This allows the heating head used in the second step to be smaller, thereby reducing the risk of the device being damaged by being pinched by the heating head.

[0048] A thirteenth aspect of the present disclosure relates to a method for producing an electric device according to the eleventh or twelfth aspect, wherein the heating temperature in the second step is at least 20° C. higher than the heating temperature in the first step.

[0049] By increasing the difference in heating temperature between the first and second steps, the metal leads and the component are prevented from being fixed in the first step, making it easier to maintain the metal leads in a state where they can slide relative to the component, thereby reducing excess space and helping to improve area efficiency.

[0050] A method for manufacturing an electrical device according to a fourteenth aspect of the present disclosure is a method for manufacturing an electrical device according to any one of the eleventh to thirteenth aspects, wherein the member includes a first layer that covers the metal lead around an axis in the first direction, and a second layer that has a lower melting point than the first layer and covers at least a portion of the first layer around the axis in the first direction.

[0051] This makes it possible to easily form a member in which heat fusion to the film and heat fusion to the metal leads can be carried out in different processes.

[0052] A method for manufacturing an electrical device according to a fifteenth aspect of the present disclosure is the method for manufacturing an electrical device according to the fourteenth aspect, wherein in the first step, the second layer and the outer casing are heat-sealed, and in the second step, the first layer and the metal lead are heat-sealed.

[0053] This allows the thermal fusion to be performed in two stages, making it possible to manufacture an electrical device that can improve area efficiency and reliability.

[0054] A method for manufacturing an electric device according to a sixteenth aspect of the present disclosure is the method for manufacturing an electric device according to the fourteenth or fifteenth aspect, wherein the first layer is longer than the second layer in the first direction.

[0055] This makes it difficult for the second layer, which melts in the first process, to come into contact with the metal lead. Therefore, at the end of the first process, the metal lead and the second layer can be prevented from being fixed together, making it easier to maintain the metal lead in a state where it can slide relative to the first and second layers. This reduces excess space and helps improve area efficiency.

[0056] A method for manufacturing an electrical device according to a seventeenth aspect of the present disclosure is a method for manufacturing an electrical device according to any one of the fourteenth to sixteenth aspects, in which, at the end of the first step, the first layer is not adhered to the metal lead.

[0057] This allows the metal leads to slide relative to the first layer at the end of the first process. For example, by moving the device closer to the electrode sealing part before the second process, the excess space can be reduced, improving area efficiency.

[0058] An 18th aspect of the present disclosure relates to a method for manufacturing an electrical device, which is a method for manufacturing an electrical device according to any one of the 11th to 17th aspects, and includes a step of sliding the metal lead relative to the member after the first step and before the second step.

[0059] This allows the device to be placed closer to the electrode sealing section before the second step, thereby reducing excess space and improving area efficiency. Furthermore, the first step can be performed with a greater distance between the electrode sealing section and the device, suppressing device degradation due to heat. This also reduces the risk of the device being accidentally pinched in the heating head of the sealing equipment and damaged, thereby improving process safety.

[0060] A method for manufacturing an electrical device according to a 19th aspect of the present disclosure is a method for manufacturing an electrical device according to any one of the 11th to 18th aspects, in which the metal lead is connected to a device to be placed in the internal space of the outer casing, and the method for manufacturing the electrical device includes a step of sealing the internal space in a reduced pressure atmosphere lower than atmospheric pressure.

[0061] This allows the exterior body and the device to be tightly attached at atmospheric pressure, thereby improving the volumetric efficiency of the device. Furthermore, the amount of gases such as oxygen sealed in the internal space can be reduced, suppressing device deterioration. Consequently, the reliability of the electrical device can be improved.

[0062] Hereinafter, embodiments of the present disclosure will be specifically described with reference to the drawings.

[0063] The embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection configurations, steps, and step sequences shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Furthermore, among the components in the following embodiments, components not described in independent claims are described as optional components.

[0064] Furthermore, each figure is a schematic diagram and is not necessarily an exact illustration. Therefore, for example, the scales of the figures do not necessarily match. Furthermore, in each figure, substantially the same components are given the same reference numerals, and redundant explanations are omitted or simplified.

[0065] Furthermore, in this specification, terms indicating the relationship between elements, such as parallel or perpendicular, terms indicating the shape of elements, such as quadrangle or trapezoid, and numerical ranges are not expressions that express only the strict meaning, but also expressions that include a substantially equivalent range, for example, a difference of about a few percent. For example, the corners of polygons such as quadrangles or trapezoids may be rounded or may have a chamfered shape.

[0066] In addition, in this specification and drawings, the x-axis, y-axis, and z-axis represent the three axes of a three-dimensional Cartesian coordinate system. In each embodiment, the x-axis direction is the sliding direction of the metal lead. The x-axis direction is an example of the first direction. When the metal lead is flat, the z-axis direction is the direction perpendicular to the main surface of the metal lead. In addition, in this specification, the positive side of the z-axis may be considered to be "upward" and the negative side of the z-axis may be considered to be "downward."

[0067] In this specification, unless otherwise specified, "planar view" refers to a view from a direction perpendicular to the main surface of a flat metal lead or the main surface of a power generating element (z-axis direction). In the case of a flat member such as a plate, layer, foil, or film, the "main surface" refers to the main surface of the member, for example, the surface with the largest area or the surface opposite to the surface with the largest area. The main surface is usually flat, but may include minute irregularities or curvatures.

[0068] Furthermore, in this specification, ordinal numbers such as "first" and "second" do not refer to the number or order of components unless otherwise specified, but are used to avoid confusion and distinguish between components of the same type.

[0069] (Embodiment 1) First, the configuration of the electrode lead according to embodiment 1 will be described with reference to Figures 1A, 1B, and 1C. Figures 1A, 1B, and 1C are a plan view, a front view, and a side view, respectively, of electrode lead 10 according to the present embodiment.

[0070] The electrode lead 10 communicates between the inside and outside of an exterior body (not shown) and is used for electrical connection to a device (not shown) placed in the internal space of the exterior body.

[0071] 1A, 1B, and 1C, the electrode lead 10 includes a metal lead 11 and a member 12 that covers the metal lead 11 around the x-axis. The member 12 includes a first layer 13 and a second layer 14. The first layer 13 and the second layer 14 are laminated in this order from the metal lead 11 side.

[0072] The metal lead 11 is a conductive metal member. The metal lead 11 is formed using a metal material such as copper or aluminum. The shape of the metal lead 11 is a rectangular flat plate that is long in the x-axis direction, but is not limited to this. The metal lead 11 is slidable in the x-axis direction relative to the member 12.

[0073] The first layer 13 covers the metal lead 11 around the x-axis. For example, the first layer 13 covers the surface of the metal lead 11 over the entire circumference around the x-axis. That is, the first layer 13 has a through-hole through which the metal lead 11 is inserted. The metal lead 11 is slidable in the x-axis direction relative to the first layer 13 via the through-hole. The first layer 13 contacts the surface of the metal lead 11.

[0074] The second layer 14 covers at least a portion of the first layer 13 around the x-axis. For example, the second layer 14 covers the outer peripheral surface of the first layer 13 around the entire circumference around the x-axis. The second layer 14 is in contact with the outer peripheral surface of the first layer 13. The second layer 14 is fixed to the first layer 13. The second layer 14 is in contact with the exterior body.

[0075] The second layer 14 has a lower melting point than the first layer 13. In other words, the melting point of the first layer 13 is higher than the melting point of the second layer 14. Specifically, the melting point of the first layer 13 is higher by 20° C. or more than the melting point of the second layer 14. This allows the second layer 14 to melt before the first layer 13 melts when the member 12 is heated.

[0076] Both the first layer 13 and the second layer 14 are resin layers containing a resin material as a main component. For example, the first layer 13 and the second layer 14 are formed using polypropylene, polyethylene, polycarbonate, polystyrene, polyvinyl chloride, ABS (Acrylonitrile Butadiene Styrene) resin, etc. For example, the melting points of the first layer 13 and the second layer 14 can be made different by appropriately adjusting the composition and / or molecular structure of each resin.

[0077] 1A, the first layer 13 is longer in the x-axis direction than the second layer 14. For example, the length L1 of the first layer 13 is 1.2 times or more the length L2 of the second layer 14. This makes it possible to prevent the melted and flowing second layer 14 from coming into contact with the metal lead 11 when the second layer 14 melts. Note that, depending on the viscosity of the flowing second layer 14, L1 may be shorter than 1.2 times L2.

[0078] 1B, the first layer 13 is thicker than the second layer 14. For example, the thickness T1 of the first layer 13 is 1.5 times or more the thickness T2 of the second layer 14. This makes it possible to strengthen the fusion of the first layer 13 to the metal lead 11. Note that, depending on the material of the first layer 13, T1 may be thinner than 1.5 times the thickness T2.

[0079] Next, the exterior body to which the electrode lead 10 is joined will be described with reference to FIGS. 2A and 2B.

[0080] Fig. 2A is a plan view of exterior body 1 to which electrode leads 10A and 10B according to the present embodiment are joined. Fig. 2B is a cross-sectional view of exterior body 1 taken along line IIB-IIB in Fig. 2A. As shown in Fig. 2A, exterior body 1 includes film 20 to which two electrode leads 10A and 10B are joined. In the present embodiment, exterior body 1 is a cylindrical or bag-shaped film 20.

[0081] Both of the two electrode leads 10A and 10B have the same configuration as the electrode lead 10 shown in FIGS. 1A to 1C. The second layer 14 of each of the two electrode leads 10A and 10B is bonded to a film 20. As shown in FIG. 2A, the two electrode leads 10A and 10B are arranged in parallel. Specifically, the two electrode leads 10A and 10B are arranged so that the sliding directions (x-axis direction) of the respective metal leads 11 are parallel.

[0082] The film 20 has an internal space 30 for accommodating a device (not shown). For example, the film 20 is formed into a cylindrical shape with the x-axis direction as the cylindrical axis, thereby forming a cylindrical exterior body 1. The device is placed in the internal space 30 of the cylindrical exterior body 1. The film 20 may also be formed into a bag-like shape with one of the openings of the tube closed, or the shape of the exterior body 1 may be bag-like. For example, the film 20 may be a bag-like film with the end on the negative side of the x-axis in Figures 2A and 2B closed. A bag-like film can be called a bottomed cylindrical film.

[0083] The film 20 is also called a laminate film and has a layered structure including, for example, two resin films and a metal layer sandwiched between the two resin films. The two resin films are primarily composed of a thermoplastic resin. The two resin films are formed using, for example, polyethylene terephthalate, polypropylene, or polyethylene. The two resin films may be formed using the same material, but may also be formed using different materials. The metal layer is formed using, for example, aluminum or nickel. By including the metal layer, the film 20 can suppress the permeation of foreign substances such as moisture and oxygen. The thickness and material of the resin films and metal layer are appropriately selected based on the sealing performance, mechanical strength, and operating temperature range of the electrical device.

[0084] The exterior body 1 may include two films. For example, two films each having a rectangular shape in plan view may be stacked one on top of the other and two opposing sides may be heat-sealed to form a cylindrical exterior body 1. Alternatively, two films each having a rectangular shape in plan view may be stacked one on top of the other and three sides may be heat-sealed to form a bag-shaped exterior body 1.

[0085] 2A and 2B, electrode leads 10A and 10B are each arranged so as to communicate between the inside and outside of package 1. The inside and outside of package 1 refer to the inside and outside of film 20. Specifically, the inside of film 20 refers to internal space 30. In the case of package 1 before sealing, internal space 30 refers to the space surrounded by the inner surface of film 20.

[0086] As can be seen by comparing Figures 2A and 2B with Figures 3A and 3B, metal leads 11 of electrode leads 10A and 10B are slidable. Figure 3A is a plan view of exterior body 1 illustrating that a portion of each of electrode leads 10A and 10B according to the present embodiment is slidable. Figure 3B is a cross-sectional view of exterior body 1 taken along line IIIB-IIIB in Figure 3A.

[0087] Metal lead 11 is slidable in the x-axis direction, allowing the amount of protrusion from package 1 to be adjusted. Meanwhile, first layer 13 and second layer 14 are both fixed to package 1. Specifically, second layer 14 is heat-sealed to film 20, thereby fixing second layer 14 to film 20. Second layer 14 and first layer 13 are fixed to each other.

[0088] Since the melting point of the second layer 14 is lower than that of the first layer 13, when the second layer 14 and the film 20 are thermally fused together, the first layer 13 and the metal leads 11 are not thermally fused together. This allows the metal leads 11 to be slidable relative to the first layer 13. The slidability of the metal leads 11 helps to improve the area efficiency and reliability of the electrical device. This will be described in more detail in the second embodiment below.

[0089] (Embodiment 2) Next, a second embodiment will be described.

[0090] In embodiment 2, an electric device including the electrode lead according to embodiment 1 will be described. The following description will focus on the differences from embodiment 1, and the description of commonalities will be omitted or simplified.

[0091] Fig. 4A is a plan view of the battery 2 according to the present embodiment. Fig. 4B is a cross-sectional view of the battery 2 taken along line IVB-IVB in Fig. 4A. Fig. 4C is a cross-sectional view of the battery 2 taken along line IVC-IVC in Fig. 4A.

[0092] The battery 2 is an example of an electrical device. The battery 2 is an all-solid-state battery. As shown in FIGS. 4A, 4B, and 4C, the battery 2 includes electrode leads 10A and 10B, a film 20, and a power-generating element 40. The film 20 is an example of an exterior body according to the present disclosure.

[0093] The power generating element 40 is an example of a device main body included in an electric device. As shown in FIGS. 4B and 4C , the power generating element 40 is disposed in the internal space 30. The power generating element 40 is a flat plate-shaped power generating element containing a solid electrolyte. The power generating element 40 is an all-solid-state battery element that does not contain an electrolytic solution.

[0094] 4B and 4C show an example in which there is a gap between each of the upper and lower surfaces of the power-generating element 40 and the inner surface of the film 20, but this is not limiting. As will be described later, when the internal space 30 is sealed in a reduced pressure atmosphere, the inner surface of the film 20 and the upper and lower surfaces of the power-generating element 40 can be brought into close contact with each other, resulting in a state in which there is substantially no gap. This also applies to FIGS. 11E and 11F, which will be described later.

[0095] Fig. 5A is a plan view of the power generating element 40 included in the battery 2 according to the present embodiment. Fig. 5B is a cross-sectional view of the power generating element 40 taken along line VB-VB in Fig. 5A. Fig. 5C is a cross-sectional view of the power generating element 40 taken along line VC-VC in Fig. 5A.

[0096] 5A, 5B, and 5C, the power generating element 40 includes an electrode active material layer 110, a counter electrode active material layer 120, a solid electrolyte layer 130, an electrode current collector 140, and a counter electrode current collector 150. The specific configuration of each layer of the power generating element 40 will be described later.

[0097] In this embodiment, as shown in FIGS. 4C and 5C, the electrode current collector 140 has a connection portion 141 for connection to the metal lead 11 of the electrode lead 10B. As shown in FIGS. 4B and 5B, the counter electrode current collector 150 has a connection portion 151 for connection to the metal lead 11 of the electrode lead 10A. As shown in FIGS. 5A, 5B, and 5C, the shape of the power generating element 40 excluding the connection portions 141 and 151 is a flat rectangular parallelepiped. The connection portions 141 and 151 are each provided so as to protrude from the rectangular parallelepiped portion of the power generating element 40. The connection between each of the connection portions 141 and 151 and the metal lead 11 is performed by, for example, but is not limited to, welding. For example, a conductive adhesive may be used, or the connection may be performed by a mechanical method such as crimping.

[0098] The power generating element included in the battery 2 is not limited to the power generating element 40 shown in Figures 5A, 5B, and 5C. For example, the battery 2 may include the power generating element 40A shown in Figures 6A and 6B or the power generating element 40B shown in Figures 6C and 6D.

[0099] Fig. 6A is a cross-sectional view of another example of the power generation element included in the battery 2 according to the present embodiment. Fig. 6B is another cross-sectional view of the power generation element 40A shown in Fig. 6A. The planar shape of the power generation element 40A is the same as the planar shape of the power generation element 40 shown in Fig. 5A. Figs. 6A and 6B correspond to the cross sections taken along line VA-VA and line VB-VB in Fig. 5A, respectively.

[0100] The power generating element 40A is a stack of multiple battery cells. Specifically, the power generating element 40A is a parallel-stacked power generating element in which multiple battery cells are electrically connected in parallel. As shown in FIGS. 6A and 6B, the power generating element 40A includes two battery cells 100A and two battery cells 100B. The battery cells 100A and the battery cells 100B are stacked alternately one by one.

[0101] Both battery cells 100A and 100B are the smallest unit that functions as a battery and are also called unit cells. Battery cell 100B has a configuration in which battery cell 100A is turned upside down. Specifically, battery cell 100A includes an electrode current collector 140, an electrode active material layer 110, a solid electrolyte layer 130, a counter electrode active material layer 120, and a counter electrode current collector 150, which are layered in this order from the negative side to the positive side of the z axis. Battery cell 100B includes a counter electrode current collector 150, a counter electrode active material layer 120, a solid electrolyte layer 130, an electrode active material layer 110, and an electrode current collector 140, which are layered in this order from the negative side to the positive side of the z axis.

[0102] Adjacent battery cells 100A and 100B share one of the electrode current collector 140 and the counter electrode current collector 150. The current collector does not need to be shared, and the electrode current collectors 140 or counter electrode current collectors 150 of the battery cells 100A and 100B may be stacked together. The two stacked current collectors may be in direct contact with each other or may be joined via a conductive material, an adhesive material, or the like.

[0103] As shown in FIG. 6A, each of the multiple counter electrode current collectors 150 protrudes from the rectangular parallelepiped portion of the power generating element 40A. The protruding portions of the multiple counter electrode current collectors 150 are connected to each other, and their tip portions function as connection portions 151 for the metal lead 11. As shown in FIG. 6B, each of the multiple electrode current collectors 140 protrudes from the rectangular parallelepiped portion of the power generating element 40A. The protruding portions of the multiple electrode current collectors 140 are connected to each other, and their tip portions function as connection portions 141 for the metal lead 11. By connecting the multiple electrode current collectors 140 to each other and connecting the multiple counter electrode current collectors 150 to each other, the multiple battery cells 100A and 100B are connected in parallel. Note that the specific method of parallel connection is not particularly limited.

[0104] Fig. 6C is a cross-sectional view of another example of the power generation element included in the battery 2 according to the present embodiment. Fig. 6D is another cross-sectional view of the power generation element 40B shown in Fig. 6C. The planar shape of the power generation element 40B is the same as the planar shape of the power generation element 40 shown in Fig. 5A. Figs. 6C and 6D correspond to the cross sections taken along line VA-VA and line VB-VB in Fig. 5A, respectively.

[0105] The power generating element 40B is a stack of multiple battery cells. Specifically, the power generating element 40B is a series-stacked power generating element in which multiple battery cells are electrically connected in series. As shown in Figures 6C and 6D, the power generating element 40B includes two battery cells 100C.

[0106] The two battery cells 100C are the smallest unit that functions as a battery and are also called unit cells. Each of the two battery cells 100C includes an electrode current collector 140, an electrode active material layer 110, a solid electrolyte layer 130, a counter electrode active material layer 120, and a counter electrode current collector 150, which are stacked in this order from the negative side to the positive side of the z axis.

[0107] Two adjacent battery cells 100C share one electrode current collector 140 and the other counter electrode current collector 150 as a single current collector. A shared current collector is also called a bipolar current collector. Note that the current collector does not need to be shared, and one electrode current collector 140 and the other counter electrode current collector 150 of two adjacent battery cells 100C may be stacked. The two stacked current collectors may be in direct contact or may be joined via a conductive material, an adhesive material, or the like.

[0108] The number of battery cells included in each of power generating elements 40A and 40B is not limited to two or four, but may be three, or five or more. Furthermore, battery 2 may include, as a power generating element, a stack of one or more parallel-stacked power generating elements and one or more series-stacked power generating elements.

[0109] Next, a method for manufacturing battery 2 according to this embodiment will be described with reference to FIGS. 7, 8A, 8B, and 9A to 9E. FIG. 7 is a flowchart showing the method for manufacturing battery 2 according to this embodiment. FIGS. 8A and 8B are each a plan view of an exterior body illustrating that a portion of the electrode lead according to this embodiment and power-generating element 40 are slidable. FIGS. 9A to 9E are each a plan view illustrating one step of the method for manufacturing battery 2 according to this embodiment. Note that, although an example using power-generating element 40 will be described below, the same applies when power-generating element 40A or 40B is used.

[0110] 7, first, the power generating element 40 is prepared (S10). Next, the electrode leads 10A and 10B are prepared (S20). Next, the film 20 is prepared (S30). The connection portions 141 and 151 of the prepared power generating element 40 are connected to the metal leads 11 of the electrode leads 10A and 10B by welding or the like.

[0111] The order of these preparation steps may be changed. Furthermore, the preparation steps may be performed simultaneously in parallel. For example, the power generating element 40 may be prepared to which the metal leads 11 of the electrode leads 10A and 10B are connected in advance. Specific methods for forming the power generating element 40 will be described later.

[0112] The metal lead 11 of each of the two electrode leads 10A and 10B is slidable relative to the first layer 13 and the second layer 14 of the member 12. Therefore, as shown in Figures 8A and 8B, as the metal leads 11 slide, the power generating element 40 connected to the two metal leads 11 also slides.

[0113] The prepared power generating element 40, electrode leads 10A and 10B, and film 20 are arranged as shown in FIG. 9A. Specifically, as shown in FIG. 9A, the power generating element 40 and electrode leads 10A and 10B are arranged on the main surface of the film 20. Next, the film 20 is folded back along the folds schematically indicated by the two-dot chain lines in FIG. 9A to cover the power generating element 40. As a result, the power generating element 40 is arranged in the internal space 30 of the tubular film 20, as shown in FIG. 9B. The electrode leads 10A and 10B are each arranged so that the inside and outside of the film 20 communicate with each other. At this time, the members 12 (specifically, the second layer 14) of the electrode leads 10A and 10B are in contact with the film 20 but are not heat-sealed. The distance between the power generating element 40 and the second layer 14 is kept as long as possible. Note that part or all of the power generating element 40 may be located outside the internal space 30 of the film 20. This reduces the possibility that the power generating element 40 will be affected by thermal load and mechanical damage in the subsequent heat fusion process.

[0114] The portion of the cylindrical film 20 along the edge on the positive side of the y-axis is joined by heat fusion. This joining by heat fusion may be performed before the power generating element 40 is arranged. That is, after the cylindrical film 20 is formed, the power generating element 40 connected to the electrode leads 10A and 10B may be inserted into the internal space 30. Alternatively, after the cylindrical film 20 is formed, the power generating element 40 may be inserted into the internal space 30, and then the connection portions 141 and 151 may be connected to the two metal leads 11, respectively.

[0115] Next, as shown in FIG. 7, a first stage of heat sealing is performed (S40, first step). Specifically, as shown in FIG. 9C, heat is applied to a heating area along one side of the film 20, thereby heat-sealing the film 20 and the second layer 14 of each of the electrode leads 10A and 10B. This forms the electrode sealing portion 21. The heating temperature at this time is higher than the melting point of the second layer 14 but lower than the melting point of the first layer 13. This allows the second layer 14 to melt and be bonded to the film 20 without melting the first layer 13. Furthermore, in the portions of the film 20 where the electrode leads 10A and 10B are not arranged, the films 20 are heat-sealed to each other.

[0116] Next, as shown in Fig. 7, the power generating element 40 is slid (S50). Specifically, as shown in Fig. 9D, the metal leads 11 of each of the electrode leads 10A and 10B and the power generating element 40 are slid in the positive direction of the x-axis. This brings the power generating element 40 closer to the electrode sealing portion 21. This reduces the excess space between the power generating element 40 and the electrode sealing portion 21. At this time, the second layer 14 and the film 20 are heat-sealed, and their relative positions are fixed, so that the power generating element 40 and the metal leads 11 are less likely to become misaligned.

[0117] Next, as shown in FIG. 7, a second-stage heat fusion is performed (S60, second step). Specifically, as shown in FIG. 9E, heat is applied to heating areas 22A and 22B to heat-fusion-bond the metal lead 11 and the first layer 13. This melts the first layer 13 and bonds it closely to the metal lead 11. The heating areas 22A and 22B each include at least a portion of the area where the first layer 13 of the electrode leads 10A and 10B overlaps with the metal lead 11 in a plan view. The heating temperature for the second-stage heat fusion is higher than the melting point of the first layer 13, and is, for example, 20° C. or more higher than the heating temperature for the first-stage heat fusion.

[0118] Because the films 20 are bonded together by the first-stage heat fusion, the heating ranges 22A and 22B may be narrower than the heating range in the first-stage heat fusion. In other words, it is sufficient to heat-bond the metal lead 11 to the first layer 13. Narrowing the heating ranges 22A and 22B allows the heating head used for heat fusion to be smaller, thereby reducing the possibility of mechanical damage to the power generating element 40. Furthermore, narrowing the heating ranges 22A and 22B reduces the thermal load on the power generating element 40, thereby suppressing deterioration of the power generating element 40.

[0119] The first heat-sealing step determines the relative positions of the second layer 14 and the film 20, making misalignment unlikely. This allows for proper heat-sealing even in narrow heating ranges 22A and 22B. This improves the sealing performance of the electrode sealing portion 21, thereby improving the reliability of the battery 2.

[0120] Next, as shown in Fig. 7, the internal space 30 is sealed (S70). Specifically, as shown in Fig. 9E, the end of the cylindrical film 20 opposite the electrode sealing portion 21 is heat-sealed to form the sealing portion 23. Before forming the sealing portion 23, the excess portion of the film 20 may be cut off. This allows the area efficiency of the battery 2 to be further improved.

[0121] The internal space 30 is sealed in a reduced pressure atmosphere lower than atmospheric pressure. The reduced pressure atmosphere is, for example, a vacuum state, but is not particularly limited as long as it is lower than atmospheric pressure. This allows the film 20 and the power-generating element 40 to be tightly attached at atmospheric pressure after sealing, thereby improving the volumetric efficiency of the battery 2. Furthermore, the amount of gases such as oxygen enclosed in the internal space 30 can be reduced, thereby suppressing deterioration of the power-generating element 40. Furthermore, improved adhesion between the film 20 and the power-generating element 40 restricts movement of the power-generating element 40 within the film 20. This prevents damage to the power-generating element 40. This improves the reliability of the battery 2. Furthermore, wrinkles and sagging are less likely to occur on the outer surface of the film 20, improving the appearance of the battery 2.

[0122] (Embodiment 3) Next, a third embodiment will be described.

[0123] In embodiment 3, a method for manufacturing the battery according to embodiment 2 will be described. The following description will focus on the differences from embodiments 1 and 2, and the description of the commonalities will be omitted or simplified.

[0124] First, the exterior body prepared in the manufacturing method of the battery according to the present embodiment will be described with reference to Figures 10A and 10B. Figure 10A is a plan view of the exterior body 3 according to the present embodiment. Figure 10B is a cross-sectional view of the exterior body 3 taken along line XB-XB in Figure 10A.

[0125] As shown in Figures 10A and 10B, the exterior housing 3 includes a film 20 to which the second layers 14 of two electrode leads 10A and 10B are previously bonded. The two electrode leads 10A and 10B are arranged parallel to each other. Specifically, the two electrode leads 10A and 10B are arranged so that the sliding directions (x-axis direction) of the metal leads 11 are parallel to each other. The film 20 can be formed into a cylindrical shape by folding the film 20 along the crease indicated by the two-dot chain line in Figure 10A.

[0126] As shown in Fig. 11A, the electrode lead 10A and the electrode lead 10B may be arranged with a fold sandwiched between them. Fig. 11A is a plan view of an exterior body 4 according to a first modification of the present embodiment. Fig. 11B is a cross-sectional view of the exterior body 4 taken along the line XIB-XIB in Fig. 11A. For example, by folding back the film 20 along the fold, the electrode lead 10B is arranged alongside the electrode lead 10A. By sandwiching the power-generating element 40 during this folding back, the power-generating element 40 can be easily connected to the electrode leads 10A and 10B.

[0127] For example, a bonding material 15A is disposed on the metal lead 11A of the electrode lead 10A. A bonding material 15B is disposed on the metal lead 11B of the electrode lead 10B. The bonding materials 15A and 15B are conductive adhesive tapes or adhesives. The metal leads 11A and 11B are the same as the metal lead 11 shown in the first embodiment.

[0128] Fig. 11C is a plan view illustrating one step in a method for manufacturing a battery using exterior package 4 shown in Fig. 11A. Fig. 11D is a plan view illustrating a step performed after the step shown in Fig. 11C.

[0129] As shown in FIG. 11C, the power generating element 40 is placed so as to overlap the bonding material 15A. In the example shown in FIG. 11C, the power generating element 40 does not have the connection portions 141 and 151. By folding the film 20 together with the electrode lead 10B at the fold, the power generating element 40 is housed inside the tubular film 20, as shown in FIG. 11D. At this time, the bonding material 15B placed on the metal lead 11B comes into contact with the power generating element 40. In this state, by applying a force in the z-axis direction, the power generating element 40 and the bonding materials 15A and 15B are pressure-welded or heat-pressurized.

[0130] Fig. 11E is a cross-sectional view of the battery taken along line XIE-XIE in Fig. 11D. Fig. 11F is a cross-sectional view of the battery taken along line XIF-XIF in Fig. 11D. Each of metal leads 11A and 11B is deformed by pressure welding or thermal pressure welding. Note that although spaces are provided between film 20 and the upper and lower surfaces of power-generating element 40, sealing in a reduced pressure atmosphere brings film 20 and power-generating element 40 into close contact, eliminating these spaces.

[0131] The metal leads 11A and 11B may be metal leads that are bent in advance according to the shape of the power generating element 40. This can prevent damage caused by deformation when joining the power generating element 40 and the metal leads.

[0132] 7, the steps of the first heat sealing step (S40), sliding the power generating element 40 (S50), the second heat sealing step (S60), and sealing the internal space 30 (S70) are carried out in this order to form a battery in which the power generating element 40 is sealed in the exterior body 4. Each step is the same as in the second embodiment.

[0133] Alternatively, only a portion of electrode leads 10A and 10B, specifically, only members 12 other than metal leads 11, may be bonded to film 20 in advance. Fig. 12A is a plan view of exterior body 5 according to Modification 2 of the present embodiment. Fig. 12B is a cross-sectional view of exterior body 5 taken along line XIIB-XIIB in Fig. 12A.

[0134] As shown in Fig. 12A, the second layer 14 of the member 12A and the second layer 14 of the member 12B are bonded to the film 20. The members 12A and 12B are the same as the member 12 shown in the first embodiment. As shown in Fig. 12B, the first layer 13 of the member 12A has a through-hole 16 for inserting the metal lead 11A. The first layer 13 of the member 12B has a similar structure.

[0135] Because the exterior body 5 does not have any metal leads, it is possible to prevent the metal leads from coming into contact with each other and being damaged during storage and use of the exterior body 5. For example, if a metal lead is inserted through the through hole 16 in the first layer 13, the metal lead is not fixed to any of the first layer 13, the second layer 14, and the film 20, and therefore there is a risk that the metal lead may become detached depending on the position of the exterior body 5. By configuring the exterior body 5 so that no metal leads are provided, it is possible to avoid damage and detachment of the metal leads.

[0136] In this modification, the metal lead is joined to the power generating element 40. Fig. 12C is a plan view of the power generating element 40 according to the second modification of the present embodiment. A metal lead 11B is connected to a connection portion 141 of the power generating element 40, and a metal lead 11A is connected to a connection portion 151. These connections are made by, for example, welding or using a conductive adhesive.

[0137] Fig. 12D is a cross-sectional view illustrating one step of the method for manufacturing a battery according to Modification 2 of the present embodiment. As shown in Fig. 12D, by sliding the power generating element 40 shown in Fig. 12C, each of the metal leads 11A and 11B can be inserted into the through-holes 16 of the members 12A and 12B, respectively.

[0138] Thereafter, after forming the film 20 into a cylindrical shape, as shown in Fig. 7, the steps of the first heat sealing step (S40), sliding the power generating element 40 (S50), the second heat sealing step (S60), and sealing the internal space 30 (S70) are carried out in this order to form a battery in which the power generating element 40 is sealed in the exterior body 5. Each step is the same as in the second embodiment.

[0139] (battery cell) Next, the specific configuration of the battery cell will be described.

[0140] 13A is a cross-sectional view showing a battery cell 100 included in the batteries according to the embodiments and modifications. As shown in FIG. 13A, the battery cell 100 includes an electrode active material layer 110, a counter electrode active material layer 120, a solid electrolyte layer 130, an electrode current collector 140, and a counter electrode current collector 150.

[0141] In this embodiment, the electrode active material layer 110 is, for example, a positive electrode active material layer, and the counter electrode active material layer 120 is, for example, a negative electrode active material layer. The electrode current collector 140 is, for example, a positive electrode current collector, and the counter electrode current collector 150 is, for example, a negative electrode current collector.

[0142] The electrode active material layer 110 includes, for example, a negative electrode active material as an electrode material. The electrode active material layer 110 is disposed opposite the counter electrode active material layer 120.

[0143] The negative electrode active material contained in the electrode active material layer 110 may be, for example, graphite, metallic lithium, or the like. As the negative electrode active material, various materials capable of extracting and inserting ions such as lithium (Li) or magnesium (Mg) may be used.

[0144] The material contained in the electrode active material layer 110 may be, for example, a solid electrolyte such as an inorganic solid electrolyte. Examples of inorganic solid electrolytes that can be used include sulfide solid electrolytes and oxide solid electrolytes. Examples of sulfide solid electrolytes that can be used include a mixture of lithium sulfide (LiS) and diphosphorus pentasulfide (P2S5). Examples of materials that can be used in the electrode active material layer 110 include a conductive material such as acetylene black, or a binder for bonding such as polyvinylidene fluoride.

[0145] The electrode active material layer 110 can be produced by applying a paste-like paint, in which the materials contained in the electrode active material layer 110 are kneaded together with a solvent, onto the surface of the electrode current collector 140 and drying the paint. In order to increase the density of the electrode active material layer 110, the electrode plate including the electrode active material layer 110 and the electrode current collector 140 may be pressed after drying. The thickness of the electrode active material layer 110 is, for example, 5 μm or more and 300 μm or less, but is not limited to this.

[0146] The counter electrode active material layer 120 is a layer containing, for example, a positive electrode material as an electrode material. The positive electrode material is a material that constitutes a counter electrode to the negative electrode material. The counter electrode active material layer 120 contains, for example, a positive electrode active material.

[0147] Examples of the positive electrode active material contained in the counter electrode active material layer 120 that can be used include lithium cobalt oxide composite oxide (LCO), lithium nickel oxide composite oxide (LNO), lithium manganese oxide composite oxide (LMO), lithium-manganese-nickel composite oxide (LMNO), lithium-manganese-cobalt composite oxide (LMCO), lithium-nickel-cobalt composite oxide (LNCO), and lithium-nickel-manganese-cobalt composite oxide (LNMCO).

[0148] As the positive electrode active material, various materials that can extract and insert ions such as Li or Mg can be used.

[0149] The counter electrode active material layer 120 may contain, for example, a solid electrolyte such as an inorganic solid electrolyte. Examples of inorganic solid electrolytes include sulfide solid electrolytes and oxide solid electrolytes. Examples of sulfide solid electrolytes include a mixture of Li2S and P2S5. The surface of the positive electrode active material may be coated with a solid electrolyte. Examples of materials that may be used in the counter electrode active material layer 120 include a conductive material such as acetylene black, or a binder such as polyvinylidene fluoride.

[0150] The counter electrode active material layer 120 can be produced by applying a paste-like paint, in which the materials contained in the counter electrode active material layer 120 are kneaded together with a solvent, onto the surface of the counter electrode current collector 150 and drying the paint. In order to increase the density of the counter electrode active material layer 120, the positive electrode plate including the counter electrode active material layer 120 and the counter electrode current collector 150 may be pressed after drying. The thickness of the counter electrode active material layer 120 is, for example, not less than 5 μm and not more than 300 μm, but is not limited to this.

[0151] The solid electrolyte layer 130 is located between the electrode active material layer 110 and the counter electrode active material layer 120. The solid electrolyte layer 130 is in contact with both the electrode active material layer 110 and the counter electrode active material layer 120. The solid electrolyte layer 130 is a layer containing an electrolyte material. As the electrolyte material, a generally known electrolyte for batteries can be used. The thickness of the solid electrolyte layer 130 may be 5 μm or more and 300 μm or less, or 5 μm or more and 100 μm or less.

[0152] The solid electrolyte may be, for example, an inorganic solid electrolyte. The inorganic solid electrolyte may be, for example, a sulfide solid electrolyte or an oxide solid electrolyte. The sulfide solid electrolyte may be, for example, a mixture of Li2S and P2S5. The solid electrolyte layer 130 may contain, in addition to the electrolyte material, a binder such as polyvinylidene fluoride.

[0153] In each embodiment and each modified example, the electrode active material layer 110, the counter electrode active material layer 120, and the solid electrolyte layer 130 are maintained in the shape of parallel plates. This makes it possible to prevent cracking or collapse due to bending. The electrode active material layer 110, the counter electrode active material layer 120, and the solid electrolyte layer 130 may be smoothly curved together.

[0154] The electrode current collector 140 and the counter electrode current collector 150 are each a conductive foil-like, plate-like, or mesh-like member. The electrode current collector 140 and the counter electrode current collector 150 may each be, for example, a conductive thin film. The electrode current collector 140 and the counter electrode current collector 150 may be made of a material such as stainless steel (SUS), aluminum (Al), copper (Cu), or nickel (Ni). The electrode current collector 140 and the counter electrode current collector 150 may be made of different materials.

[0155] The thickness of each of the electrode current collector 140 and the counter electrode current collector 150 is, for example, not less than 5 μm and not more than 100 μm, but is not limited to this.

[0156] An electrode active material layer 110 is provided on the main surface of the electrode current collector 140. The electrode active material layer 110 may be provided in contact with the main surface of the electrode current collector 140, or may be provided via another layer, such as a bonding layer or current collector layer, containing a conductive material.

[0157] A counter electrode active material layer 120 is provided on the main surface of the counter electrode current collector 150. The counter electrode active material layer 120 may be provided in contact with the main surface of the counter electrode current collector 150, or may be provided via another layer, such as a bonding layer or a current collector layer, containing a conductive material.

[0158] The battery cell 100 does not necessarily have to include the electrode current collector 140 and the counter electrode current collector 150. Figures 13B and 13C are cross-sectional views showing other examples of battery cells included in the batteries according to the embodiments and modifications.

[0159] The battery cell 100D shown in Fig. 13B is a battery cell that does not include a counter electrode current collector 150. The battery cell 100E shown in Fig. 13C is a battery cell that does not include an electrode current collector 140. For example, by stacking at least two or more of the battery cells 100, 100D, and 100E, the power generating element 40A shown in Figs. 6A and 6B and the power generating element 40B shown in Figs. 6C and 6D can be easily formed.

[0160] Next, a specific process of the step of preparing a power generating element made up of a battery cell or a stack of multiple battery cells (S10 in FIG. 7) will be described.

[0161] First, for example, a paste-like paint prepared by kneading the materials contained in the electrode active material layer 110 together with a solvent is applied to the main surface of the electrode current collector 140 and dried to form the electrode active material layer 110. In order to increase the density of the electrode active material layer 110, the electrode active material layer 110 applied to the electrode current collector 140 may be pressed after drying.

[0162] Next, for example, a paste-like paint obtained by kneading the materials contained in the counter electrode active material layer 120 together with a solvent is applied to the main surface of the counter electrode current collector 150 and dried to form the counter electrode active material layer 120. In order to increase the density of the counter electrode active material layer 120, the counter electrode active material layer 120 applied to the counter electrode current collector 150 may be pressed after drying. Note that the formation of the electrode active material layer 110 and the formation of the counter electrode active material layer 120 may be performed either first, or may be performed simultaneously in parallel.

[0163] Next, for example, a paste-like paint prepared by kneading the materials contained in the solid electrolyte layer 130 together with a solvent is applied to the main surfaces of the electrode active material layer 110 and / or the counter electrode active material layer 120 and dried to form the solid electrolyte layer 130 or a portion thereof. Alternatively, the solid electrolyte layer 130 may be formed by applying the paste-like paint to a release film and drying it.

[0164] Next, for example, the electrode current collector 140, the electrode active material layer 110, the solid electrolyte layer 130, the counter electrode active material layer 120, and the counter electrode current collector 150 are stacked in this order and pressed together to form the battery cell 100 as the power generating element 40. Pressurization methods that can be used include, for example, plate pressing, roll pressing, and isostatic pressing. Furthermore, to improve the adhesion and density of each layer, heating may be applied during pressing. The heating temperature may be set within a range that does not cause chemical changes in the materials of each layer due to heat, for example, 60°C or higher and 200°C or lower.

[0165] When preparing the power generating element 40A shown in FIGS. 6A and 6B or the power generating element 40B shown in FIGS. 6C and 6D as a power generating element, the battery cells 100 manufactured through the above steps are stacked. Alternatively, the battery cells 100D or 100E manufactured by a similar manufacturing method may be stacked. When stacking, for example, the multiple battery cells 100 may be integrated by bonding them with an adhesive. Alternatively, the multiple battery cells 100 may be integrated by, for example, stacking all of the above components and applying pressure to bond them together. The edges of the integrated battery cells 100, electrode current collector 140, and counter electrode current collector 150 do not need to be flush, and a step may be provided for each battery cell 100.

[0166] (Other embodiments) While the electrode lead, the electrical device, the exterior body, and the method for manufacturing the electrical device according to one or more aspects have been described above based on the embodiments, the present disclosure is not limited to these embodiments. As long as they do not deviate from the gist of the present disclosure, various modifications that a person skilled in the art can make to the present embodiments and configurations constructed by combining components of different embodiments are also included within the scope of the present disclosure.

[0167] For example, although the battery is an all-solid-state battery in the above example, the present invention is not limited to this. The power generating element may contain an electrolyte. The battery may be a cylindrical battery containing an electrolyte.

[0168] Furthermore, the electric device does not have to be a power generating element. That is, the device housed inside the exterior body does not have to be a power generating element. For example, the electric device may be an electronic device having a predetermined function, such as a capacitor, inductor, or integrated circuit.

[0169] Furthermore, various modifications, substitutions, additions, omissions, etc. can be made to the above-described embodiments within the scope of the claims or their equivalents. [Industrial Applicability]

[0170] The present disclosure can be widely used in batteries for electronic devices, electrical appliances, electric vehicles, and various other electric devices. [Explanation of symbols]

[0171] 1, 3, 4, 5 Exterior body 2 batteries 10, 10A, 10B electrode leads 11, 11A, 11B metal leads 12, 12A, 12B parts 13 1st layer 14 2nd layer 15A, 15B Bonding material 16 through holes 20 Film 21 Electrode sealing part 22A, 22B Heating Range 23 Sealing part 30 Interior Space 40, 40A, 40B power generation elements 100, 100A, 100B, 100C, 100D, 100E battery cells 110 Electrode active material layer 120 Counter electrode active material layer 130 Solid electrolyte layer 140 Electrode current collector 141, 151 Connection 150 Counter electrode current collector

Claims

1. An electrode lead that communicates the inside and outside of the exterior body in a first direction, A metal lead; a first layer covering the metal lead around an axis in the first direction; a second layer having a lower melting point than the first layer and covering at least a portion of the first layer around an axis in the first direction; the first layer contacts the metal lead; the second layer contacts the outer casing; Electrode leads.

2. the first layer is longer than the second layer in the first direction; The electrode lead of claim 1 .

3. The length of the first layer is 1.2 times or more the length of the second layer. The electrode lead of claim 2 .

4. The melting point of the first layer is higher than the melting point of the second layer by 20°C or more. The electrode lead of claim 1 .

5. The first layer is thicker than the second layer. The electrode lead of claim 1 .

6. The thickness of the first layer is 1.5 times or more the thickness of the second layer. The electrode lead according to claim 5 .

7. The electrode lead according to any one of claims 1 to 6; The exterior body, Electrical devices.

8. A metal lead; a first layer covering the metal lead around an axis in a first direction; a second layer having a lower melting point than the first layer and covering at least a portion of the first layer around an axis in the first direction; the metal lead is slidable in the first direction relative to the first layer; Electrode leads.

9. The second layer of each of two electrode leads, each of which is the electrode lead of claim 8, comprises one or more films bonded together. Exterior body.

10. The two electrode leads are arranged in parallel. The exterior body according to claim 9.

11. a first step of thermally fusing a member covering the metal lead and an outer casing around an axis in a first direction; a second step of thermally fusing the member and the metal lead together after the first step, A method for manufacturing an electrical device.

12. The heating range in the second step is narrower than the heating range in the first step. The method for manufacturing an electrical device according to claim 11 .

13. The heating temperature in the second step is 20°C or more higher than the heating temperature in the first step. The method for manufacturing an electrical device according to claim 11 .

14. The member is a first layer covering the metal lead around an axis in the first direction; a second layer having a melting point lower than that of the first layer and covering at least a portion of the first layer around the axis in the first direction, The method for manufacturing an electrical device according to any one of claims 11 to 13.

15. In the first step, the second layer and the outer casing are heat-sealed, In the second step, the first layer and the metal lead are thermally fused together. The method for manufacturing an electrical device according to claim 14 .

16. the first layer is longer than the second layer in the first direction; The method for manufacturing an electrical device according to claim 14 .

17. At the end of the first step, the first layer is not bonded to the metal lead. The method for manufacturing an electrical device according to claim 14 .

18. the step of sliding the metal lead relative to the member after the first step and before the second step; The method for manufacturing an electrical device according to any one of claims 11 to 13.

19. a device disposed in the internal space of the exterior body is connected to the metal lead; The method for manufacturing an electrical device includes a step of sealing the internal space in a reduced pressure atmosphere lower than atmospheric pressure. The method for manufacturing an electrical device according to any one of claims 11 to 13.

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