JP2022149993A - power storage device - Google Patents

Abstract

To provide a power storage device which can shorten the time for bonding two members (a first member and a second member) to each other.SOLUTION: A power storage device 10 provided with power storage elements 200 comprises a first member (an outer packaging lid 120) and a second member (an outer packaging body 110) which are bonded to each other. The first member has: a body part (a lid body part 121); and a high-transmissivity part 130 which is disposed so as to be embedded in the body part, and which has light transmissivity higher than that of the body part. The high-transmissivity part 130 has: an exposed part 140 which is exposed from the body part; a bonding part 151 which is bonded to the second member; and a light passage route 160 which is disposed inside the body part so as to guide light from the exposed part 140 to the bonding part 151.SELECTED DRAWING: Figure 5

Description

The present invention relates to a power storage device including power storage elements.

2. Description of the Related Art Conventionally, a power storage device that includes a power storage element and that includes two members (a first member and a second member) that are joined together is known. For example, in Patent Document 1, a case that houses a battery module that includes a plurality of battery cells (power storage elements) has a lid (first member) and a main body (second member), and the lid is attached to the main body. A battery pack (power storage device) configured to close an opening is disclosed.

JP 2018-37185 A

In power storage devices, it is desired to shorten the manufacturing time (assembling time) and improve the productivity. For this reason, there is a demand for shortening the time required to join two members (a first member and a second member) to be joined included in the power storage device. However, when joining two members (the first member and the second member) such as the lid and the main body of the case as in the conventional power storage device, it is common to join them by adhesion, heat sealing, or the like. , which may take some time.

The present invention was made by the inventors of the present invention by newly paying attention to the above problem, and is an electricity storage device capable of shortening the time required to join two members (first member and second member). intended to provide

To achieve the above object, a power storage device according to one aspect of the present invention is a power storage device including a power storage element, comprising a first member and a second member that are joined to each other, the first member comprising a main body and a high-transmittance portion embedded in the main body portion and having a higher light transmittance than the main body portion, wherein the high-transmittance portion is an exposed portion exposed from the main body portion. , a joint portion that is joined to the second member; and a light passing path that is disposed in the body portion and guides light from the exposed portion to the joint portion.

According to this, in the power storage device, the high-transmittance portion embedded in the main body portion of the first member includes the exposed portion from the main body portion, the joint portion with the second member, and from the exposed portion to the joint portion in the main body portion. and a light passage for guiding light. In this manner, the high transmission portion having a light passage path for guiding light from the exposed portion to the joint portion with the second member is arranged in the first member while being embedded in the main body portion. As a result, when the first member and the second member are joined, by irradiating the exposed portion of the high transmittance portion with light such as a laser beam, the light passes through the light passage from the exposed portion, Joined with the member. Here, in general, bonding by irradiating light such as laser light can shorten the time compared to bonding by adhesion, heat sealing, or the like. Therefore, by joining the first member and the second member by irradiating light, it is possible to shorten the time required to join the first member and the second member.

The light passing path may have a bent portion in which the path through which light passes is bent or curved.

According to this, in the first member, the light passage path has the bent portion, so that when light is guided from the exposed portion to the joint portion, the light can bend and reach the joint portion. Thereby, when joining the first member and the second member, even if some object is placed between the light source and the part to be joined, the light source or the part to be joined is not moved. Light can arrive at the junction. Therefore, the time for moving the light source or the joining target site is not required, so that the time for joining the first member and the second member can be further shortened.

The joint portion may be joined to the second member without interposing the body portion.

According to this, in the first member, the joint portion can be firmly joined to the second member by directly joining the joint portion to the second member without interposing the main body portion. As a result, the first member and the second member can be joined more firmly even when the time for joining the first member and the second member is shortened.

The joint portion may be arranged to extend along the second member, and the light passage path may be arranged to extend along the extending direction of the joint portion.

According to this, in the first member, the light passage path is arranged to extend along the extension direction of the joint, so that the first member and the second member are arranged along the extension direction of the joint. It is possible to shorten the time required to join the members.

The light passing path may have a branching portion where the path through which light passes is branched.

According to this, in the first member, the light passage path has the branched portion, so that when the first member and the second member are joined, light can branch and reach a plurality of joined portions. As a result, since it is possible to perform bonding at a plurality of locations at once, it is possible to shorten the time required to bond the first member and the second member.

The present invention can be realized not only as such a power storage device, but also as a first member or a combination of a first member and a second member.

According to the power storage device of the present invention, it is possible to shorten the time required to join two members (the first member and the second member).

1 is a perspective view showing an appearance of a power storage device according to an embodiment; FIG. FIG. 2 is an exploded perspective view showing each component when the power storage device according to the embodiment is exploded; FIG. 10 is a perspective view illustrating a configuration of a high-transmittance portion according to the embodiment, and a method of joining an exterior cover body to an exterior body main body; FIG. 4 is a cross-sectional view for explaining the configuration of a high-transmittance portion and a technique for joining an exterior cover body to a wall portion of an exterior body body according to an embodiment; FIG. 4 is a cross-sectional view for explaining the configuration of a high-transmittance portion and a technique for joining an exterior cover body to a wall portion of an exterior body body according to an embodiment; 4A and 4B are a top view and a cross-sectional view illustrating a method of joining an exterior lid according to an embodiment to an exterior body. FIG. FIG. 7 is a cross-sectional view showing the configuration of a high-transmittance portion according to Modification 1 of the embodiment; FIG. 11 is a top view for explaining a method of joining an exterior lid according to Modification 2 of the embodiment to an exterior body.

Hereinafter, power storage devices according to embodiments of the present invention (including modifications thereof) will be described with reference to the drawings. It should be noted that the embodiments described below are all comprehensive or specific examples. Numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of constituent elements, manufacturing processes, order of manufacturing processes, and the like shown in the following embodiments are examples, and are not intended to limit the present invention. In each drawing, dimensions and the like are not strictly illustrated. In each figure, the same reference numerals are given to the same or similar components.

In the following description and drawings, the direction in which a plurality of energy storage elements are arranged, the direction in which a pair of long sides of a container of one energy storage element face each other, or the thickness direction of an energy storage element is defined as the X-axis direction. The direction in which a pair of electrode terminals in one storage element are arranged or the direction in which a pair of short sides of a container for one storage element are opposed is defined as the Y-axis direction. The direction in which the main body and lid of the exterior body of the power storage device are aligned, the direction in which the main body and lid of the container of one power storage element are aligned, the direction in which the power storage element and the bus bar are aligned, or the vertical direction is defined as the Z-axis direction. defined as These X-axis direction, Y-axis direction, and Z-axis direction are directions that cross each other (perpendicularly in this embodiment). Although the Z-axis direction may not be the vertical direction depending on the mode of use, the Z-axis direction will be described below for convenience of explanation.

In the following description, for example, the positive direction of the X-axis indicates the arrow direction of the X-axis, and the negative direction of the X-axis indicates the direction opposite to the positive direction of the X-axis. The same applies to the Y-axis direction and the Z-axis direction. Expressions indicating relative directions or orientations, such as parallel and orthogonal, also include cases where the directions or orientations are not strictly speaking. For example, two directions are orthogonal, not only means that the two directions are completely orthogonal, but also substantially orthogonal, that is, for example, a difference of about several percent It is also meant to include Furthermore, in the following description, the expression "insulation" means "electrical insulation".

(Embodiment)
[1 General description of power storage device 10]
First, the configuration of power storage device 10 will be described. FIG. 1 is a perspective view showing the appearance of power storage device 10 according to the present embodiment. FIG. 2 is an exploded perspective view showing each component when power storage device 10 according to the present embodiment is exploded.

Power storage device 10 is a device capable of charging electricity from the outside and discharging electricity to the outside, and has a substantially rectangular parallelepiped shape in the present embodiment. For example, the power storage device 10 is a battery module (assembled battery) used for power storage or power supply. Specifically, the power storage device 10 is, for example, an automobile, a motorcycle, a watercraft, a ship, a snowmobile, an agricultural machine, a construction machine, or a rolling stock for an electric railway. It is used as a battery etc. Examples of such vehicles include electric vehicles (EV), hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), and gasoline vehicles. Examples of railway vehicles for the electric railway include electric trains, monorails, linear motor cars, and hybrid trains having both diesel engines and electric motors. The power storage device 10 can also be used as a stationary battery or the like for home or business use.

As shown in FIG. 1, the power storage device 10 includes an exterior body 100, and as shown in FIG. It is In addition to the components described above, the power storage device 10 includes a busbar frame for positioning the busbars 300, restraining members (end plates, side plates, etc.) for restraining the plurality of power storage elements 200, and interposed between the power storage elements 200. A spacer, a circuit board for monitoring the state of charge and the state of discharge of the storage element 200, and an electric device such as a relay may be provided. An adhesive or the like may be placed between the power storage elements 200 and between the power storage elements 200 and the exterior body 100 to bond and fix them.

The exterior body 100 is a box-shaped (substantially rectangular parallelepiped) container (module case) that constitutes a housing (outer shell) of the power storage device 10 . That is, the exterior body 100 is arranged outside the plurality of power storage elements 200 and the plurality of bus bars 300, fixes the power storage elements 200 and the like at predetermined positions, and protects them from impacts and the like. The exterior body 100 (excluding the high-transmittance portion 130 described later) is made of, for example, polycarbonate (PC), polypropylene (PP), polyethylene (PE), polyphenylene sulfide resin (PPS), polyphenylene ether (PPE (including modified PPE)). , polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyether ether ketone (PEEK), tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA), polytetrafluoroethylene (PTFE), polyether sulfone (PES) , ABS resin, or an insulating member such as a composite material thereof. The exterior body 100 thereby prevents the power storage element 200 and the like from coming into contact with an external metal member or the like. Note that the exterior body 100 may be made of a conductive member such as metal as long as the insulation of the power storage element 200 and the like is maintained.

The exterior body 100 has an exterior body main body 110 that constitutes the main body of the exterior body 100 and an exterior body lid 120 that constitutes the lid of the exterior body 100 . The exterior body main body 110 is a bottomed rectangular cylindrical housing (casing) having an opening facing the positive direction of the Z axis, and accommodates the power storage element 200 and the like. The exterior body main body 110 has a pair of opposing walls 111 and 112 on both sides in the X-axis direction, and a pair of opposing walls 113 and 114 on both sides in the Y-axis direction. It has a wall portion 115 on the negative direction side. The wall portion 111 is a side wall portion of the exterior body main body 110 in the positive direction of the X axis, and the wall portion 112 is a side wall portion of the exterior body main body 110 in the negative direction of the X axis. The wall portion 113 is a side wall portion of the exterior body main body 110 in the negative Y-axis direction, and the wall portion 114 is a side wall portion of the exterior body main body 110 in the positive X-axis direction.

The wall portions 111 and 112 are rectangular and flat wall portions (short side wall portions) that form the short side surfaces of the exterior body 100, and are arranged to face the long side surfaces of the container 210 of the power storage element 200 in the X-axis direction. be done. Walls 111 and 112 are adjacent to walls 113 , 114 and 115 and have a smaller outer surface area than walls 113 and 114 . The wall portions 113 and 114 are rectangular and flat wall portions (long side wall portions) that form the long side surfaces of the exterior body 100, and are arranged to face the short side surfaces of the container 210 of the power storage element 200 in the Y-axis direction. be done. Walls 113 and 114 are adjacent to walls 111 , 112 and 115 and have a larger outer surface area than walls 111 and 112 . Wall portion 115 is a rectangular and flat wall portion (bottom wall portion) that forms the bottom surface of exterior body 100 and is arranged to face the bottom surface of container 210 of storage element 200 in the Z-axis direction. Wall 115 adjoins walls 111 , 112 , 113 and 114 . Note that depending on the number, shape, etc. of the storage elements 200, the wall portions 111 and 112 may be long side wall portions, and the wall portions 113 and 114 may be short side wall portions.

The exterior cover 120 is a flat rectangular member that is joined to the exterior body 110 to close the opening of the exterior body 110 . The exterior lid 120 has a lid body portion 121 and a high transmittance portion 130 . The lid main body portion 121 is the main body portion of the exterior lid 120 that occupies most of the exterior lid 120 . In the present embodiment, a portion of the exterior lid 120 other than the high-transmittance portion 130 is referred to as a lid main body portion 121 .

The lid body portion 121 has an external terminal arrangement portion 121a and a lid projection portion 121b. The external terminal placement portion 121a is a plate-like portion parallel to the XY plane where a pair of positive and negative external terminals 122 (a positive external terminal and a negative external terminal) are arranged. Power storage device 10 charges electricity from the outside and discharges electricity to the outside through the pair of external terminals 122 . The lid projecting portion 121b is a T-shaped projecting portion that projects in the Z-axis positive direction from the external terminal placement portion 121a when viewed from the Z-axis direction. That is, the cover main body portion 121 has a rectangular recessed shape at both ends in the negative Y-axis direction and both ends in the X-axis direction where the pair of external terminals 122 are arranged.

The exterior body main body 110 and the lid body main body portion 121 may be formed of members of the same material, or may be formed of members of different materials. The exterior body cover 120 is an example of a first member, and the exterior body main body 110 is an example of a second member. That is, the exterior lid 120 and the exterior main body 110 are examples of the first member and the second member that are joined together. The lid main body portion 121 is an example of a main body portion of the first member.

The high transmittance portion 130 is arranged in a state of being embedded in the lid main body portion 121, and is a portion having a higher light transmittance than the lid body main portion 121. 120 is joined to the exterior body main body 110 . The high transmittance portion 130 is an annular member arranged along the outer peripheral edge of the lid body portion 121 when viewed from the Z-axis direction. For example, the high transmittance portion 130 is integrated (integrally formed) with the lid body portion 121 by being embedded in the lid body portion 121 by insert molding or the like. The high-transmittance portion 130 is, for example, a member that is made by processing a fiber used for an optical fiber into a plate shape with a thickness of about several millimeters and forming it into a ring shape. In the present embodiment, the high transmittance portion 130 is arranged along the outer edge of the lid protruding portion 121b. As a result, the high transmittance portion 130 is formed in a T-shaped annular shape when viewed from the Z-axis direction, with the X-axis direction central portion and the Y-axis negative direction end portions protruding in the Y-axis negative direction. A detailed description of the configuration of the high-transmittance portion 130 and the method of joining the exterior cover 120 to the exterior body 110 using the high-transmittance portion 130 will be given later.

The storage element 200 is a secondary battery (single battery) capable of charging and discharging electricity, and more specifically, a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. . Energy storage element 200 has a flattened rectangular parallelepiped shape (square shape), and in the present embodiment, eight energy storage elements 200 are arranged side by side in the X-axis direction. Note that the shape of the power storage element 200 is not limited to a rectangular parallelepiped shape, and may be an oval columnar shape, an elliptical columnar shape, a cylindrical shape, or a polygonal columnar shape other than a rectangular parallelepiped. The number of power storage elements 200 to be arranged is not particularly limited, and only one power storage element 200 may be arranged. The storage element 200 is not limited to a non-aqueous electrolyte secondary battery, and may be a secondary battery other than a non-aqueous electrolyte secondary battery, or may be a capacitor. The power storage element 200 may be a primary battery that can use stored electricity without being charged by the user, instead of a secondary battery. The storage element 200 may be a battery using a solid electrolyte. The storage element 200 may be a pouch-type storage element.

The storage element 200 includes a container 210 and a pair of electrode terminals 220 (positive electrode side and negative electrode side). Inside the container 210, an electrode assembly, a pair of current collectors (positive electrode side and negative electrode side), an electrolytic solution (non-aqueous electrolyte), and the like are accommodated. Gaskets are arranged therebetween, but illustration and detailed description thereof are omitted. As the electrolytic solution, the type is not particularly limited as long as it does not impair the performance of the electric storage element 200, and various kinds can be selected. In addition to the above-described components, the storage element 200 includes spacers disposed on the side or below the electrode body, an insulating film that wraps the electrode body and the like, an insulating film (such as a shrink tube) that covers the outer surface of the container 210, and the like. may be placed.

The container 210 is a rectangular parallelepiped (square or box-shaped) case having a container body with an opening and a container lid closing the opening of the container body. The container 210 has a pair of long side surfaces on both side surfaces in the X-axis direction, a pair of short side surfaces on both side surfaces in the Y-axis direction, and a bottom surface on the negative Z-axis direction side. The container cover is provided with a gas discharge valve that releases the pressure when the pressure inside the container 210 rises, and a liquid injection part for injecting an electrolytic solution into the container 210. . The material of the container 210 is not particularly limited, and can be, for example, a weldable metal such as stainless steel, aluminum, aluminum alloy, iron, or plated steel plate, but resin can also be used.

The electrode terminal 220 is a terminal member (a positive electrode terminal and a negative electrode terminal) of the storage element 200 arranged on the container lid of the container 210, and electrically connects the positive electrode plate and the negative electrode plate of the electrode assembly via the current collector. Connected. That is, the electrode terminal 220 is made of a metal material for leading electricity stored in the electrode body to the external space of the storage element 200 and for introducing electricity into the internal space of the storage element 200 to store the electricity in the electrode body. It is a member made of The electrode terminal 220 is made of aluminum, aluminum alloy, copper, copper alloy, or the like.

The electrode assembly is a power storage element (power generation element) formed by laminating a positive electrode plate, a negative electrode plate, and a separator. The positive electrode plate is formed by forming a positive electrode active material layer on a positive electrode substrate layer, which is a collector foil made of a metal such as aluminum or an aluminum alloy. The negative electrode plate is formed by forming a negative electrode active material layer on a negative electrode substrate layer, which is a collector foil made of a metal such as copper or a copper alloy. As the active material used for the positive electrode active material layer and the negative electrode active material layer, any known material can be appropriately used as long as it can intercalate and deintercalate lithium ions. The electrode body includes a wound electrode body formed by winding electrode plates (a positive electrode plate and a negative electrode plate), and a laminated (stacked) electrode formed by stacking a plurality of flat plate-shaped electrode plates. The electrode body may have any form, such as a body or a bellows-shaped electrode body in which an electrode plate is folded into a bellows shape.

The current collector is a conductive current collector (a positive electrode current collector and a negative electrode current collector) electrically connected to the electrode terminal 220 and the electrode body. The current collector is joined to the electrode terminal 220 and the electrode body by welding, crimping, or the like. The positive electrode current collector is made of aluminum, an aluminum alloy, or the like, like the positive electrode substrate layer of the positive electrode plate, and the negative electrode current collector, like the negative electrode substrate layer of the negative electrode plate, is made of copper, a copper alloy, or the like. there is

The bus bar 300 is a plate-shaped rectangular member that is arranged above the plurality of storage elements 200 and connected to the electrode terminals 220 (positive terminals or negative terminals) of the plurality of storage elements 200 . Thereby, the bus bar 300 connects the electrode terminals 220 of the plurality of storage elements 200 to each other, and connects the electrode terminals 220 of the storage elements 200 at the ends and the external terminals 122 via other bus bars (not shown). Connecting. Bus bar 300 is made of a conductive member made of metal such as aluminum, aluminum alloy, copper, or copper alloy. In the present embodiment, bus bar 300 connects two storage elements 200 in parallel to form four sets of storage element groups, and the four sets of storage element groups are connected in series. The form of connection is not particularly limited.

[2 Description of Configuration of High Transmittance Part 130 and Method of Joining with Exterior Body Main Body 110]
Next, the configuration of the high-transmittance portion 130 of the exterior lid 120 and the method of joining the exterior lid 120 to the exterior body 110 using the high-permeability portion 130 will be described in detail. FIG. 3 is a perspective view illustrating the configuration of the high-transmittance portion 130 according to the present embodiment and a method of joining the exterior cover 120 to the exterior main body 110. As shown in FIG. Specifically, FIG. 3 shows the configuration of the high-permeability portion 130 of the exterior lid 120 shown in FIG. It is a figure explaining a method.

FIG. 4 is a cross-sectional view illustrating the configuration of the high-transmittance portion 131 according to the present embodiment, and a method of joining the exterior cover 120 to the wall 111 of the exterior main body 110 . Specifically, FIG. 4 shows the lid body portion 121 and the high transmission portion 131 of the exterior body lid body 120 shown in FIG. FIG. 3 is a cross-sectional view showing the configuration when the cross section is viewed from the negative direction of the Y-axis. FIG. 5 is a cross-sectional view illustrating the configuration of the high-transmittance portion 134 and a method of joining the exterior cover 120 to the wall 113 of the exterior main body 110 according to the present embodiment. Specifically, FIG. 5 shows the lid body portion 121 and the high transmission portion 134 of the exterior body lid body 120 shown in FIG. FIG. 2 is a cross-sectional view showing the configuration when the cross section is viewed from the positive direction of the X-axis.

6A and 6B are a top view and a cross-sectional view illustrating a method of joining the exterior cover 120 to the exterior main body 110 according to the present embodiment. Specifically, (a) of FIG. 6 is a top view showing the configuration of the process of joining the exterior lid 120 to the exterior body 110 when viewed from the positive direction of the Z axis. (b) of FIG. 6 is a cross-sectional view showing the configuration of the cross section obtained by cutting (a) of FIG. 6 along a plane including the VIb-VIb line and parallel to the YZ plane, viewed from the positive direction of the X axis. . (c) of FIG. 6 is a cross-sectional view showing the configuration of a cross section obtained by cutting (a) of FIG. 6 along a plane including the VIc-VIc line and parallel to the YZ plane, viewed from the positive direction of the X axis. .

As described above, the high transmittance portion 130 is arranged in a state of being embedded in the lid body portion 121 (the body portion of the first member), and has a higher light transmittance (or transmittance) than the lid body portion 121. It is a high part. A high light transmittance (or transmittance) means that light is transmitted at a high rate (easily transmitted) when the light is irradiated. In the present embodiment, the light is a laser beam used for joining (welding or welding) two members (exterior cover 120 and exterior main body 110). In other words, in this embodiment mode, high light transmittance (or transmittance) means that the laser light passes through the material at a high rate (easily passes through) when the laser light is irradiated. Note that when the two members are joined by using light other than laser light such as an electron beam, high light transmittance (or transmittance) means the case where light such as an electron beam is irradiated. Secondly, it means that the ratio of light such as the electron beam to pass through is high (easily pass through). Further, as described above, in the present embodiment, the high-transmittance portion 130 is formed of fibers used for optical fibers, but the high-transmittance portion 130 is made of a material having a higher light transmittance than the lid main body portion 121. and the material of the high-transmittance portion 130 is appropriately changed according to the kind of light.

As shown in FIG. 3, in the exterior lid 120, the high transmission portion 130 (high transmission portions 131 to 138) is arranged along the outer edge of the lid protruding portion 121b of the lid main body portion 121. As shown in FIG. The high transmittance portion 131 is arranged to extend in the Y-axis direction near the end of the high transmittance portion 130 in the positive direction of the X-axis and in the positive direction of the Y-axis. The high transmittance portion 132 is arranged to extend in the X-axis direction at the center of the high transmittance portion 130 in the Y-axis direction and close to the X-axis plus direction (the Y-axis plus direction of the external terminal 122 in the X-axis plus direction). . The high transmittance portion 133 is arranged to extend in the Y-axis direction near the high transmittance portion 130 in the plus direction of the X axis and the minus direction of the Y axis (the minus direction of the external terminal 122 in the plus direction of the X axis). . The high transmittance portion 134 is arranged to extend in the X-axis direction at the end portion of the high transmittance portion 130 in the negative Y-axis direction and the central portion in the X-axis direction. The high transmittance portion 135 is arranged to extend in the Y-axis direction close to the high transmittance portion 130 in the negative X-axis direction and close to the negative Y-axis direction (the positive X-axis direction of the external terminal 122 in the negative X-axis direction). . The high-transmittance portion 136 is arranged to extend in the X-axis direction at the center portion of the high-transmittance portion 130 in the Y-axis direction and toward the negative direction of the X-axis (the positive direction of the Y-axis of the external terminal 122 in the negative direction of the X-axis). . The high transmittance portion 137 is arranged to extend in the Y-axis direction at the end portion of the high transmittance portion 130 in the negative direction of the X-axis and toward the positive direction of the Y-axis. The high transmission portion 138 is arranged to extend in the X-axis direction at the Y-axis plus direction end of the high transmission portion 130 .

As shown in FIGS. 3 to 5, the high transmittance portion 130 (high transmittance portions 131 to 138) has an exposed portion 140, a joint portion 151, and a light passage 160. As shown in FIG. In addition, as shown in FIG. 4 , the exposed portion 140 included in the high transmittance portion 131 is also referred to as the exposed portion 141 , and the light passage 160 included in the high transmittance portion 131 is also referred to as the light passage 161 . As shown in FIG. 5 , the exposed portion 140 of the high transmittance portion 134 is also referred to as the exposed portion 142 , and the light passage 160 of the high transmittance portion 134 is also referred to as the light passage 162 .

The exposed portion 140 is a portion of the high-transmittance portion 130 that is exposed from the lid main body portion 121 (main body portion). Specifically, the exposed portion 140 is a portion disposed at the end of the high transmittance portion 130 in the positive Z-axis direction and exposed to the outside from the surface (outer surface) of the lid main body portion 121 in the positive Z-axis direction.

The joint portion 151 is a portion that is joined to the exterior body main body 110 (second member). The joint portion 151 is a joint portion on the side of the high transmittance portion 130 when the high transmittance portion 130 and the exterior body main body 110 are joined, and is arranged at the end portion of the high transmittance portion 130 in the negative Z-axis direction. Specifically, by irradiating the high-transmittance portion 130 with a laser beam, the high-transmittance portion 130 and the exterior body main body 110 are joined (welded or welded) to form the joint portion 150 . In other words, the joint portion 150 is a melted portion formed by melting the exterior body main body 110 by being irradiated with laser light from the high-transmitting portion 130 and melting the high-transmitting portion 130 with the heat. The exterior body main body 110 is formed of a member that absorbs light more than the highly transmissive portion 130, and the irradiated portion melts when irradiated with laser light. As a result, the joint 150 has a joint 151 that is a melted portion on the high transmission portion 130 side and a joint 152 that is a melted portion on the exterior body main body 110 side (see FIGS. 4 and 5). ).

In the present embodiment, the exterior body cover 120 and the exterior body main body 110 are joined over the entire circumference of the opening at the end of the exterior body 110 in the positive Z-axis direction. In other words, the joint portion 150 (151 and 152) is a quadrangular ring-shaped portion when viewed from the Z-axis direction, which is formed along the entire circumference of the opening at the end of the exterior body 110 in the positive Z-axis direction. In this manner, the joint portion 151 is arranged to extend along the exterior body main body 110 (second member).

The joint portion 151 is joined to the exterior body main body 110 (second member) without interposing the lid body main body portion 121 (main body portion). That is, in the state before the exterior body lid 120 and the exterior body main body 110 are joined, the portion of the high-transmittance portion 130 that is joined to the exterior body body 110 (the end in the negative Z-axis direction) is the lid body body portion 121 . exposed from Therefore, the high transmittance portion 130 is joined to the exterior body main body 110 without the lid body main body portion 121 interposed therebetween, thereby forming the joint portion 151 .

The light passage path 160 is a portion that is arranged in the lid main body portion 121 (main body portion) and guides light from the exposed portion 140 to the joint portion 151 . The light passage path 160 is a portion that connects the exposed portion 140 and the joint portion 151 by connecting the end portion in the positive Z-axis direction to the exposed portion 140 and the end portion in the negative Z-axis direction to the joint portion 151 . Specifically, light passage path 160 connects the entire exposed portion 140 and the entire bonded portion 151 to guide light from the entire exposed portion 140 to the entire bonded portion 151 . That is, the light passage path 160 is arranged to extend along the extending direction of the exposed portion 140 and is arranged to extend along the extending direction of the joint portion 151 . Since the joint portion 151 is arranged to extend along the exterior body main body 110 , it can be said that the light passage path 160 is arranged to extend along the exterior body body 110 .

For example, as shown in FIG. 4 , in the high transmittance portion 131 , the light passage path 161 extends linearly in the Z-axis direction from the exposed portion 141 toward the joint portion 151 . It is a plate-like portion parallel to the YZ plane, which is arranged along the wall portion 111 so as to extend in the Y-axis direction as well. In such a configuration, when the exposed portion 141 is irradiated with the laser beam L1, the laser beam L1 travels straight along the light passage path 161 in the negative Z-axis direction, and reaches the end of the wall portion 111 in the positive Z-axis direction. part is irradiated. As a result, the end portion of the wall portion 111 in the positive Z-axis direction melts, and the heat melts the end portion in the negative Z-axis direction of the high transmission portion 131 to form the joint portion 150 (151 and 152). In the above description, it is assumed that the laser light L1 travels straight through the light passage 161. However, the concept of straight travel includes that the laser light L1 travels through the light passage 161 while repeating total reflection within the light passage 161. Including going with. The same applies to the following.

As shown in FIG. 5, in the high transmittance portion 134, the light passage path 162 extends in the Z-axis direction and the Y-axis direction from the exposed portion 142 toward the joint portion 151 in an L-shape. It is a plate-like portion arranged to extend along the wall portion 113 of the body main body 110 in the X-axis direction. Specifically, the light passage path 162 has a first path 162a, a second path 162b, a bent portion 162c, and an inclined portion 162d. The first path 162a is a flat plate-like portion that extends linearly in the Z-axis direction and the X-axis direction and is parallel to the XZ plane. The second path 162b is a flat plate-like portion that extends linearly in the Y-axis direction and the X-axis direction and is parallel to the XY plane. The bent portion 162c is located between the first path 162a and the second path 162b, and is a portion where the path through which light passes is bent or curved. In other words, the bent portion 162c is a portion extending in the X-axis direction so as to bend from the negative Z-axis direction to the negative Y-axis direction. The inclined portion 162d is arranged at the end of the second path 162b in the negative Y-axis direction, and the portion inclined in the negative Y-axis direction toward the negative Z-axis direction extends in the X-axis direction.

In such a configuration, when the exposed portion 142 is irradiated with the laser beam L2, the laser beam L2 travels straight along the first path 162a of the light passage path 162 in the negative Z-axis direction and is reflected by the bent portion 162c. to change direction in the negative direction of the Y-axis. Then, the laser beam L2 travels straight along the second path 162b in the negative direction of the Y-axis, is reflected by the inclined portion 162d, changes direction in the negative direction of the Z-axis, and irradiates the end portion of the wall portion 113 in the positive direction of the Z-axis. be done. As a result, the end of the wall portion 113 in the positive direction of the Z-axis is melted, and the heat melts the end of the second path 162b in the negative Y-axis direction and the negative direction of the Z-axis. ) is formed.

In this way, as shown in FIGS. 6A and 6B, the exterior lid 120 and the central portion of the wall portion 113 in the X-axis direction are joined via the high-transmittance portion 134 . Specifically, a light source (mirror) for a laser beam used in a galvanometer scanner or the like is provided at the center position of the exterior lid 120 in the Z-axis plus direction of the exterior lid 120 when viewed from the Z-axis direction. 20 are placed. In this case, in the central portion of the wall portion 113 in the X-axis direction, the lid protrusion 121b is arranged between the light source 20 and the site to be welded, so that the site to be welded is directly irradiated with laser light from the light source 20 Can not do it. Therefore, by irradiating the high transmittance portion 134 with the laser light L2 from the light source 20, the exterior body cover 120 and the central portion of the wall portion 113 in the X-axis direction are joined. Also in the bonding between the exterior cover body 120 and the wall part 114, since the lid body projection part 121b is arranged between the light source 20 and the part to be joined, the laser light L3 from the light source 20 is transmitted to the high transmission part 138. By irradiating, the exterior body cover 120 and the wall part 114 are joined.

On the other hand, as shown in FIGS. 6A and 6C, at the end of the wall portion 113 in the positive direction of the X axis, the lid projecting portion 121b or the like is provided between the light source 20 and the joining target portion. Since no object is placed, the laser beam L4 can be directly emitted from the light source 20 to the joining target site. Therefore, by directly irradiating the part to be joined with the laser light L4 from the light source 20 without passing through the high transmission part 130, the exterior body cover 120 and the end of the wall part 113 in the positive direction of the X axis are joined. (penetration welding). In this way, the exterior body cover 120 and the end of the wall portion 113 in the positive direction of the X axis can be joined without using the high-transmittance portion 132 , so the high-transmittance portion 132 may not be provided. The exterior body cover 120 and the end of the wall portion 113 in the positive direction of the X axis may be joined via the high-transmittance portion 134 without providing the high-transmittance portion 132 . A high-transmittance portion 132 is provided, and through the high-transmittance portion 132, the X-axis plus direction end portion of the exterior body cover 120 and the wall portion 113 may be joined. The same applies to the joint between the exterior body cover 120 and the end portion of the wall portion 113 in the negative direction of the X axis.

The same applies to the joint between the exterior cover 120 and the wall portion 111 . That is, in joining the exterior lid 120 and the portion of the wall portion 111 closer to the positive direction of the Y axis, the high transmittance portion 131 is irradiated with the laser light L1 from the light source 20, whereby the exterior lid 120 and the wall portion 111 are joined together. A portion of the portion 111 closer to the Y-axis plus direction is joined. In joining the exterior lid 120 and the portion of the wall portion 111 closer to the Y-axis negative direction, the bonding target portion is directly irradiated with laser light from the light source 20, thereby bonding the exterior lid 120 and the wall portion 111 together. The portion closer to the Y-axis minus direction is joined. Therefore, a configuration in which the high transmission portion 133 is not provided may be adopted. The same applies to the joint between the exterior cover 120 and the wall portion 112 . For example, the laser light from the light source 20 is rotated counterclockwise (rotation R1 in (a) of FIG. 6) to bond the walls 114, 112, 113 and 111 to the exterior cover 120 in this order. In this way, the exterior cover 120 and the entire walls 111 to 114 of the exterior main body 110 are joined together.

[3 Explanation of effects]
As described above, according to power storage device 10 according to the present embodiment, highly permeable portion 130 embedded in lid body portion 121 (main body portion) of exterior lid body 120 (first member) is exposed. It has a portion 140 , a joint portion 151 with the exterior body main body 110 (second member), and a light passage path 160 that guides light from the exposed portion 140 to the joint portion 151 within the lid body main body portion 121 . In this manner, the high transmittance portion 130 having the light passage 160 that guides the light from the exposed portion 140 to the joint portion 151 with the exterior main body 110 is embedded in the lid body 121. to place. As a result, when the exterior cover 120 and the exterior body 110 are joined together, the exposed portion 140 of the high transmittance portion 130 is irradiated with light such as laser light, and the light passes through the light passage 160 from the exposed portion 140. Then, it is joined to the exterior body main body 110 at the joining portion 151 . Here, in general, bonding by irradiating light such as laser light can shorten the time compared to bonding by adhesion, heat sealing, or the like. Therefore, by joining the exterior body lid 120 and the exterior body main body 110 by irradiating light, it is possible to shorten the time required for bonding the exterior body lid 120 and the exterior body main body 110 .

The configuration in which the high transmission portion 130 is embedded in the lid body portion 121 has the following advantages compared to the configuration in which the high transmission portion 130 is attached to the lid body portion 121 . When the high-transmittance portion 130 is attached to the lid body portion 121, the high-transmittance portion 130 is easily separated from the lid body portion 121. 130 is difficult to separate from the lid main body portion 121 . Since the high-transmittance portion 130 may be embedded in the lid body portion 121 when forming the lid body portion 121, there is no need to perform the step of attaching the high-transmittance portion 130 to the lid body portion 121. An exterior lid 120 can be formed. Embedding the high transmittance portion 130 in the lid body portion 121 makes it more difficult for light passing through the high transmittance portion 130 to leak to the outside than by attaching the high transmittance portion 130 to the lid body portion 121 .

The configuration in which the high-transmittance portion 130 is embedded in the lid main body portion 121 has the following advantages compared to the configuration in which the entire exterior lid 120 is the high-transmittance portion 130 . Instead of using the entire exterior lid body 120 as the high transmission portion 130, the lid body body portion 121 is configured to be embedded in the lid body body portion 121. (function as a lid that closes the exterior body 100). For example, even if the high-transmittance portion 130 is made of a weak material, the exterior lid 120 can be reinforced by forming the lid body portion 121 of a strong material. Even if the high transmittance portion 130 is made of a material that is difficult to process, by forming the lid main body portion 121 from a material that is easy to process, the exterior lid 120 can be processed into a complicated shape. Even if the high-transmittance portion 130 is made of an expensive material, by using an inexpensive material for the lid body portion 121, the cost of the exterior lid body 120 can be reduced.

In the exterior body cover 120 , the light passage path 162 has the bent portion 162 c so that the light can reach the joint portion 151 while being bent when the light is guided from the exposed portion 142 to the joint portion 151 . As a result, even when an object (lid protruding portion 121b, etc.) is placed between the light source 20 and the part to be joined when the exterior cover 120 and the exterior main body 110 are joined, , the light can reach the joint 151 without moving the light source 20 or the part to be joined. This eliminates the need to move the light source 20 or the bonding target site, thereby further shortening the time required to bond the exterior body cover 120 and the exterior body main body 110 . Since it is not necessary to move the light source 20 or the part to be joined, the exterior body cover 120 and the exterior body main body 110 can be easily bonded.

In the exterior lid body 120 , the junction part 151 is directly bonded to the exterior body body 110 without interposing the lid body body part 121 , so that the junction part 151 can be firmly bonded to the exterior body body 110 . As a result, the exterior cover 120 and the exterior main body 110 can be joined more firmly even when the time for bonding the exterior lid 120 and the exterior body 110 is shortened.

In the exterior lid 120 , the light passage path 160 is arranged to extend along the extending direction of the joint 151 , so that the exterior lid 120 and It is possible to shorten the time required to join the exterior body main body 110 . By arranging the light passage path 160 to extend along the extension direction of the joint portion 151, light can be easily transmitted to the joint portion 151 when the exterior body cover 120 and the exterior body main body 110 are joined. Since it can be reached, the exterior body cover 120 and the exterior body main body 110 can be easily joined.

[4 Description of modified example]
(Modification 1)
Next, Modification 1 of the above embodiment will be described. FIG. 7 is a cross-sectional view showing the configuration of the high transmittance portion 130 (139) according to Modification 1 of the present embodiment. 7 is a diagram corresponding to the high transmission portion 130 (131 or 134) in FIG. 4 or 5. FIG.

As shown in FIG. 7 , in this modified example, a high transmission portion 139 is arranged as the high transmission portion 130 . The high transmission portion 139 has a light passage 163 as the light passage 160 . Since the rest of the configuration of this modification is the same as that of the above-described embodiment, detailed description thereof will be omitted.

The light passing path 163 has a first path 163a, a second path 163b, and branch portions 163c and 163d. The branching portions 163c and 163d are portions where the paths through which light passes are branched. In this embodiment, the first path 163a is branched into a plurality of second paths 163b by branch portions 163c and 163d. Specifically, one first route 163a is branched into two routes at a branching portion 163c, and the two branched routes are each branched into two routes at two branching portions 163d. are branched into two second paths 163b. Accordingly, when the first path 163a is irradiated with the laser beam L6, the laser beam L6 is branched into four second paths 163b via the branching portions 163c and 163d, and bonding is performed in each of the second paths 163b. done.

As described above, according to the power storage device according to the present modification, the same effects as those of the above-described embodiment can be obtained. In particular, in this modification, the light passage path 163 has the branch portions 163c and 163d, so that when the exterior lid 120 and the exterior body main body 110 are joined, the light is branched and reaches the joint portions 151 at a plurality of locations. can arrive. As a result, since it is possible to perform joining at a plurality of locations at once, it is possible to shorten the time required to join the exterior body cover 120 and the exterior body main body 110 . Since the light passing path 163 has the branch portions 163c and 163d, light can easily reach the joint portions 151 at a plurality of locations, so that the exterior body cover 120 and the exterior body main body 110 can be easily bonded. Since the laser beam can be split and multiple parts can be joined at once, it can contribute to the provision of products with little distortion.

(Modification 2)
Next, Modification 2 of the above embodiment will be described. FIG. 8 is a top view illustrating a method of joining the exterior lid 120 to the exterior body 110 according to Modification 2 of the present embodiment. Specifically, FIG. 8 is a diagram corresponding to (a) of FIG.

As shown in FIG. 8 , in this modification, the light source 20 is arranged at the central position of the four power storage devices 10 in the positive Z-axis direction of the four power storage devices 10 when viewed from the Z-axis direction. In such a configuration, for example, the laser light from the light source 20 is rotated counterclockwise like the rotation R2 in the power storage device 10 in the negative direction of the X axis and the positive direction of the Y axis, and the exterior body cover 120 are joined to the walls of the exterior body main body 110 . Then, the laser light from the light source 20 is rotated counterclockwise along the rotation R3 to irradiate the power storage device 10 in the negative direction of the X-axis and the negative direction of the Y-axis. At this time, also in the power storage device 10 , the laser light from the light source 20 is rotated counterclockwise like the rotation R<b>2 to bond the exterior cover 120 to each wall of the exterior main body 110 . In this way, the exterior body lids 120 and the exterior body main bodies 110 in the four power storage devices 10 are sequentially joined.

Thus, in the method of manufacturing a plurality of power storage devices 10 , one light source 20 is used to irradiate the first power storage device 10 with laser light, and the laser light moves (rotates) within the first power storage device 10 . ) to join the exterior body cover 120 (first member) and the exterior body main body 110 (second member). Next, using the one light source 20, the laser light is moved (rotated) to the second power storage device 10, and the laser light is moved (rotated) in the second power storage device 10 to The (first member) and the exterior body main body 110 (second member) are joined. Similarly, the third power storage device 10 and the like are also joined using the one light source 20 .

As described above, according to the power storage device according to the present modification, the same effects as those of the above-described embodiment can be obtained. In particular, in this modified example, the exterior lids 120 and the exterior body main bodies 110 in the plurality (four) of the power storage devices 10 can be collectively joined by the single light source 20 . It is possible to shorten the time required for joining the 110 . In addition, in this modified example, the number of power storage devices 10 joined by one light source 20 is not particularly limited.

(Other modifications)
Although the power storage device according to the present embodiment (including modifications thereof) has been described above, the present invention is not limited to the above embodiment. In other words, the embodiments disclosed this time are illustrative in all respects and are not restrictive, and the scope of the present invention includes all changes within the meaning and range equivalent to the claims. included.

For example, in the above embodiment, the exterior cover body 120 is exemplified as the first member, and the exterior body main body 110 is exemplified as the second member. The exterior body cover 120 may be exemplified. That is, the high transmittance portion 130 may be provided in the exterior body main body 110 . Alternatively, the first member and the second member may be any two members provided in power storage device 10 that are joined to each other. For example, the first member and the second member may be the container lid and the container body of the container 210 of the storage elements 200, the spacer and the exterior body between the storage elements 200, or the spacer and the busbar frame. and any other two members. Regarding materials, the first member and the second member may be a resin member and a metal member, a metal member and a resin member, or a metal member and a metal member.

In the above-described embodiment, the exposed portion 140 of the high transmittance portion 130 is a portion exposed to the outside from the lid main body portion 121 . However, the exposed portion 140 may be covered (hidden) with another member so that the exposed portion 140 is not exposed to the outside.

In the above embodiment, the joint portion 151 of the high-transmittance portion 130 is joined to the exterior body main body 110 without the lid body main body portion 121 interposed therebetween. However, the joint portion 151 may be joined to the exterior body main body 110 via the lid body main body portion 121 .

In the above-described embodiment, all of the joints 150 of the exterior lid 120 and the exterior main body 110 are joined by the above method. The parts need not be joined in the manner described above.

A form constructed by arbitrarily combining each component provided in the above-described embodiment and its modifications is also included within the scope of the present invention.

The present invention can be realized not only as such a power storage device, but also as a first member or a combination of a first member and a second member.

INDUSTRIAL APPLICABILITY The present invention can be applied to a power storage device having a power storage element such as a lithium ion secondary battery.

10 Power storage device 20 Light source 100 Exterior body 110 Exterior body main body 111, 112, 113, 114, 115 Wall part 120 Exterior lid body 121 Lid body body part 121a External terminal arrangement part 121b Lid body projection part 122 External terminal 130, 131, 132, 133, 134, 135, 136, 137, 138, 139 highly transmissive portions 140, 141, 142 exposed portions 150, 151, 152 joint portions 160, 161, 162, 163 light passage paths 162a, 163a first path 162b, 163b second path 162c bent portion 162d inclined portion 163c, 163d branch portion 200 storage element 210 container 220 electrode terminal 300 bus bar

Claims (5)

A power storage device comprising a power storage element,
comprising a first member and a second member joined together;
The first member has a body portion and a high-transmittance portion that is embedded in the body portion and has a higher light transmittance than the body portion,
The high transmission portion is
an exposed portion exposed from the main body;
a joint portion that is joined to the second member;
and a light passage path arranged in the main body portion for guiding light from the exposed portion to the joint portion. The power storage device according to claim 1, wherein the light passage path has a bent portion in which a path through which light passes is bent or curved. The power storage device according to claim 1 or 2, wherein the joint portion is joined to the second member without interposing the main body portion. The joint portion is arranged to extend along the second member,
The power storage device according to any one of claims 1 to 3, wherein the light passage path is arranged to extend along the extending direction of the joint portion. The power storage device according to any one of claims 1 to 4, wherein the light passage path has a branching portion at which a path through which light passes is branched.

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