JP2022137620A - Power storage element - Google Patents

Abstract

To provide a power storage element in which a closing member can be easily bonded to a container.SOLUTION: A power storage element 10 comprises: a container 100 on which a liquid port 122 for an electrolyte is formed, and which has a wall part (a lid body 120) extending in a first direction (an X-axis direction); and a closing member 300 which is disposed in a second direction (a Z-axis direction) intersecting the first direction of the wall part in a manner without being fitted into the wall part, and which is bonded to the wall part so as to close the liquid port 122. The closing member 300 is formed such that a distance between the liquid port 122 and a third-direction edge on each of both sides in a third direction (a Y-axis direction) intersecting the first and second directions may be greater than a distance between the liquid port 122 and a first-direction edge on at least one side in the first direction.SELECTED DRAWING: Figure 3

Description

TECHNICAL FIELD The present invention relates to an electric storage element that includes a container and a closing member that closes a liquid port of the container.

2. Description of the Related Art Conventionally, an electric storage element is known that includes a container in which a liquid port for an electrolytic solution is formed and a closing member that closes the liquid port. For example, Patent Literature 1 discloses a sealed battery (power storage element) that includes a battery case (container) having a liquid inlet (liquid port) and a sealing plug (closure member) that seals the liquid inlet. It is

JP 2018-45888 A

In the electric storage element having the conventional structure, it may be difficult to join the closing member to the container. For example, in the electric storage device disclosed in Patent Document 1, the small-diameter portion of the sealing plug has an outer diameter that is substantially the same as the diameter of the injection port, and the small-diameter portion of the sealing plug corresponds to the injection port. While inserted, the sealing plug is welded to the battery case. That is, in the electric storage element disclosed in Patent Document 1, the closing member is fitted (press-fitted) into the liquid port to be fixed to the container, and in this state, the closing member is joined to the container. However, in this case, when the closure member is fitted (press-fitted) into the liquid port, the container or the closure member is deformed. be.

SUMMARY OF THE INVENTION The present invention was made by the inventors of the present application by newly paying attention to the above problem, and an object of the present invention is to provide an electric storage element in which a closing member can be easily joined to a container.

To achieve the above object, an electric storage element according to an aspect of the present invention includes a container having a wall portion formed with a liquid port for an electrolytic solution and extending in a first direction; a blocking member arranged in a second direction intersecting with the direction intersecting the first direction and being joined to the wall portion so as to block the liquid port, the blocking member being disposed in the first direction without being fitted to the wall portion; and the distance between the edge in the third direction and the liquid port on both sides in the third direction intersecting the second direction is equal to the edge in the first direction and the liquid port on at least one side in the first direction greater than the distance to

According to this, the electric storage element includes the closing member that is joined to the wall portion of the container that extends in the first direction without engaging with the wall portion, and the closing member has ends on both sides in the third direction. The distance between the edge and the liquid port is greater than the distance between the edge and the liquid port on at least one side in the first direction. In this way, by joining the blocking member to the wall without engaging the wall, it is possible to suppress deformation of the wall and the blocking member when the blocking member is joined to the wall, thereby preventing joint failure. can be suppressed. Further, since an electrode terminal, a gas discharge valve, or the like is arranged between the blocking member and the short side of the wall, it is difficult to access the blocking member from the short side of the wall. It is difficult to fix (temporarily fix) the closing member to the wall from the short side of the wall at the time of joining. On the other hand, the blocking member can be easily accessed from the long side of the wall, and the blocking member can be easily fixed (temporarily fixed) to the wall from the long side of the wall. Therefore, the distance between the edge and the liquid port on both sides in the third direction (the long side of the wall) is equal to the edge on at least one side in the first direction (the short side of the wall). Place it so that it is larger than the distance from the liquid port. As a result, it is possible to easily access the blocking member from both sides of the long side of the wall and temporarily fix the blocking member to the wall from both sides of the long side of the wall. At the time of joining, the closing member can be easily and stably temporarily fixed to the wall. Therefore, the closure member can be easily and stably temporarily fixed to the wall portion while suppressing the occurrence of poor joining when the closure member is joined to the wall portion, so that the closure member can be easily joined to the container.

In the closing member, the distance between the third direction edge and the liquid port on both sides in the third direction is greater than the distance between the first direction edge and the liquid port on both sides in the first direction. can be made larger.

If the size of the closing member arranged on the wall of the container is too large, it may cause problems. In order to temporarily fix the closing member to the wall, the distance between the edge and the liquid port in the third direction should be large. can. For this reason, the closing member is formed such that the distance between the edge and the liquid port on both sides in the third direction is larger than the distance between the edge and the liquid port on both sides in the first direction. As a result, it is possible to easily and stably temporarily fix the closing member to the wall from both sides of the wall in the third direction, while suppressing problems caused by the size of the closing member becoming too large.

The closing member may have a length in the third direction longer than a length in the first direction.

According to this, the length of the closing member in the third direction is longer than the length in the first direction, so that the distance between the edge in the third direction and the liquid port is equal to the edge in the first direction and the liquid port. It is possible to easily realize a configuration that is larger than the distance from the . As a result, the closing member can be easily and stably temporarily fixed to the wall portion, so that the closing member can be easily joined to the container.

In the closing member, the length in the first direction of the end portion in the third direction may be shorter than the length in the first direction of the central portion in the third direction.

If the size of the closing member arranged on the wall of the container is too large, it may cause problems. In addition, since the end portion of the blocking member in the third direction may be of a size that allows the blocking member to be temporarily fixed to the wall, the length in the first direction is shorter than the central portion of the blocking member in the third direction. can. For this reason, the closing member is formed such that the end portions in the third direction are shorter in the first direction than the central portion in the third direction. As a result, it is possible to easily and stably temporarily fix the closing member to the wall from both sides of the wall in the third direction, while suppressing problems caused by the size of the closing member becoming too large.

The closing member may be joined to the wall portion at a position closer to the liquid port than the center position in the third direction between the edge in the third direction and the liquid port.

According to this, the closing member is joined to the wall portion at a position closer to the liquid port than the center position in the third direction between the edge in the third direction and the liquid port, so that the closing member can be The end of the closing member for temporary fixing to the wall can be widened. As a result, the closing member can be easily and stably temporarily fixed to the wall portion, so that the closing member can be easily joined to the container.

The closing member may have a shaft portion that is inserted without being fitted into the liquid port.

According to this, since the closing member has a shaft portion into which the closing member is inserted without being fitted into the liquid port, the closing member can be easily moved to the wall portion without deformation of the wall portion and the closing member due to fitting. can be positioned at As a result, when the closing member is joined to the wall, the closing member can be easily arranged on the wall, so that the closing member can be easily joined to the container.

The present invention can be realized not only as such an electric storage element, but also as a combination of a container and a closing member.

According to the electric storage element of the present invention, the closure member can be easily joined to the container.

1 is a perspective view showing an appearance of a power storage device according to an embodiment; FIG. FIG. 4 is a perspective view showing a configuration before and after joining a closing member included in a power storage element according to an embodiment to a container; 3A and 3B are a top view and a cross-sectional view showing the configuration of the closing member according to the embodiment; FIG. FIG. 11 is a top view showing the configuration of a closing member according to Modification 1 of the embodiment; FIG. 11 is a top view showing the configuration of a closing member according to Modification 1 of the embodiment; FIG. 11 is a top view showing the configuration of a closing member according to Modification 1 of the embodiment; FIG. 11 is a cross-sectional view showing the configuration of a closing member according to Modification 2 of the embodiment; FIG. 11 is a cross-sectional view showing the configuration of a closing member according to Modification 3 of the embodiment;

Hereinafter, an electric storage element according to an embodiment (including modifications thereof) of the present invention 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 pair of electrode terminals (positive electrode side and negative electrode side, the same applies hereinafter) of the storage element are arranged, or the direction in which the short sides of the container face each other is defined as the X-axis direction. The direction facing the long side of the container or the thickness direction of the container is defined as the Y-axis direction. The direction in which the container body and lid of the container are aligned, the direction in which the lid and closing member are aligned, or the vertical direction is defined as the Z-axis direction. 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. When simply referred to as the X-axis direction, it indicates either or both of the X-axis plus direction and the X-axis minus direction. The same applies to the Y-axis direction and the Z-axis direction. Hereinafter, the X-axis direction may also be referred to as the first direction, the Z-axis direction may also be referred to as the second direction, and the Y-axis direction may also be referred to as the third 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 parallel" means not only that the two directions are completely parallel, but also that they are substantially parallel, that is, that there is a difference of, for example, several percent. Furthermore, in the following description, the expression "insulation" means "electrical insulation".

(Embodiment)
[1 General Description of Electricity Storage Element 10]
First, with reference to FIGS. 1 and 2, a general description of the storage device 10 according to the present embodiment will be given. FIG. 1 is a perspective view showing the appearance of a power storage device 10 according to this embodiment. FIG. 2 is a perspective view showing the configuration before and after joining the closure member 300 provided in the storage device 10 according to the present embodiment to the container 100 . Specifically, (a) of FIG. 2 shows the state before joining the closing member 300 to the container 100, and (b) of FIG. 2 shows the state after joining the closing member 300 to the container 100. ing.

The electric storage element 10 is a secondary battery (single battery) capable of charging and discharging electricity, and is specifically a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. The power storage element 10 can be used as a battery or the like for driving a moving body such as an automobile, a motorcycle, a watercraft, a ship, a snowmobile, agricultural machinery, a construction machinery, or a railway vehicle for an electric railway, or for starting an engine, for example. Used. 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. In addition, the electric storage device 10 can also be used as a stationary battery or the like used for home use or a power generator.

Note that the storage element 10 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 device 10 may be a primary battery that can use stored electricity without being charged by the user, instead of a secondary battery. The storage element 10 may be a battery using a solid electrolyte. The storage element 10 may be a pouch-type storage element. In the present embodiment, a flat rectangular parallelepiped (square) power storage element 10 is illustrated, but the shape of the power storage element 10 is not limited to a rectangular parallelepiped shape, and may be a cylindrical shape, an oval cylindrical shape, an elliptical cylindrical shape, or a rectangular parallelepiped shape. Alternatively, it may have a polygonal columnar shape other than a rectangular parallelepiped.

As shown in FIG. 1 , the energy storage device 10 includes a container 100 , a pair of electrode terminals 200 (positive electrode side and negative electrode side, the same applies hereinafter), a pair of upper gaskets 210 , and a closing member 300 . A pair of lower gaskets, an electrode assembly, a pair of current collectors, an electrolytic solution (non-aqueous electrolyte), and the like are accommodated inside the container 100, but illustration thereof is 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 10, and various kinds can be selected.

In addition to the components described above, the electric storage element 10 may include spacers disposed on the sides or below the electrode body, an insulating film that wraps the electrode body and the like, and the like. Furthermore, an insulating film (such as a shrink tube) covering the outer surface of the container 100 may be arranged around the container 100 . The material of the insulating film is not particularly limited as long as it can ensure the insulation necessary for the electric storage element 10, but for example, insulating resin such as PC, PP, PE, PPS, PET, PBT or ABS resin, Epoxy resin, Kapton, Teflon (registered trademark), silicone, polyisoprene, and polyvinyl chloride can be exemplified.

The container 100 is a rectangular parallelepiped (square or box-shaped) case having a container body 110 with an opening and a lid 120 closing the opening of the container body 110 . The container main body 110 is a rectangular tubular member that constitutes the main body of the container 100 and has a bottom, and an opening is formed in the positive direction of the Z axis. The lid body 120 is a rectangular plate-like member that constitutes the lid portion of the container 100 , and is arranged to extend in the X-axis direction (first direction) in the positive Z-axis direction of the container body 110 . The container 100 has a structure in which the inside is hermetically sealed by joining the container main body 110 and the cover 120 by welding or the like after the electrode body and the like are accommodated inside the container main body 110 . The material of the container 100 (container main body 110 and lid 120) is not particularly limited, but can be weldable (bondable) metal such as stainless steel, aluminum, aluminum alloy, iron, and plated steel plate. can also be used.

With such a configuration, the container 100 has a pair of long side surfaces 101 on both side surfaces in the Y-axis direction, a pair of short side surfaces 102 on both side surfaces in the X-axis direction, and a lower surface on the negative Z-axis direction side. It will have a bottom surface 103 . The short side 102 is a rectangular planar portion that forms the short side of the container 100 . Short side 102 is adjacent to long side 101 and bottom surface 103 and has a smaller area than long side 101 . The long side 101 is a rectangular planar portion that forms the long side of the container 100 . Long side 101 is adjacent to short side 102 and bottom 103 and has a larger area than short side 102 . The bottom surface 103 is a rectangular planar portion that forms the bottom surface of the container 100 and is arranged adjacent to the long side surface 101 and the short side surface 102 .

As shown in FIGS. 1 and 2, the lid 120 is formed with a gas exhaust valve 121 and a liquid port 122 . The gas discharge valve 121 is a safety valve that releases the pressure when the pressure inside the container 100 rises excessively. The liquid port 122 is an electrolyte liquid port formed in the lid 120 in order to inject the electrolyte into the container 100 when the electric storage element 10 is manufactured. Specifically, the liquid port 122 is a circular through hole penetrating the lid 120 in the Z-axis direction. In the present embodiment, the gas discharge valve 121 is arranged at the center in the X-axis direction and the center in the Y-axis direction of the lid 120, and the liquid port 122 is located near the minus direction of the X-axis and at the center in the Y-axis of the lid 120. placed in the department. That is, the liquid port 122 is arranged between the gas exhaust valve 121 and the electrode terminal 200 in the negative direction of the X-axis. Note that the gas exhaust valve 121 and the liquid port 122 may be arranged at any position on the lid 120 . The lid 120 is an example of a wall of the container 100 .

The closing member 300 is a liquid filling plug that is arranged in the Z-axis direction (the second direction that intersects with the first direction) of the lid 120 of the container 100 and is joined to the lid 120 to close the liquid port 122 of the lid 120. be. In the present embodiment, the closing member 300 is a sealing component (sealing plate) that seals the liquid port 122 and has an oval shape when viewed from the Z-axis direction. Specifically, the closing member 300 is arranged in the positive Z-axis direction of the lid 120 after the electrolytic solution is injected from the liquid opening 122 into the container 100 when the electric storage element 10 is manufactured. is joined by welding or the like to close the liquid port 122 . As a result, as shown in FIG. 2B, a substantially annular joint 400 is formed by joining (welding) the closing member 300 and the lid 120 so as to surround the liquid port 122 . The material of the closing member 300 is not particularly limited, but any metal or the like that can be used for the container 100 can be used. In particular, the closing member 300 is made of a material that can be joined (welded) to the container 100 (the lid 120), such as the same material as the container 100 (the lid 120). A detailed description of the configuration of the closing member 300 will be given later.

The electrode terminal 200 is a terminal member (a positive electrode terminal and a negative electrode terminal) of the storage element 10 arranged on the lid 120 of the container 100 . The electrode terminal 200 is electrically connected to the positive electrode plate and the negative electrode plate of the electrode body through the current collector. In other words, the electrode terminal 200 is made of metal for leading electricity stored in the electrode body to the external space of the storage element 10 and for introducing electricity into the internal space of the storage element 10 to store the electricity in the electrode body. It is a member made of The electrode terminal 200 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. A microporous sheet made of resin, a non-woven fabric, or the like can be used as the separator. In the present embodiment, the electrode body is formed by stacking electrode plates (a positive electrode plate and a negative electrode plate) in the Y-axis direction. 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 type (stacked) electrode body formed by stacking a plurality of flat plate-shaped electrode plates. or a bellows-shaped electrode body in which an electrode plate is folded into a bellows shape.

The current collector is a conductive member (a positive electrode current collector and a negative electrode current collector) that electrically connects the electrode terminal 200 and the electrode body. The current collector is connected (joined) to the electrode terminal 200 and the electrode body by crimping, welding, 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 upper gasket 210 is a gasket that is arranged between the lid 120 and the electrode terminal 200 to insulate and seal between the lid 120 and the electrode terminal 200 . The lower gasket is a gasket that is placed between the lid 120 and the current collector to insulate and seal between the lid 120 and the current collector. The upper gasket 210 and the lower gasket may be made of any material as long as it has insulating properties.

[2 Description of Closing Member 300]
Next, the configuration of the closing member 300 will be described in detail. 3A and 3B are a top view and a cross-sectional view showing the configuration of the closing member 300 according to this embodiment. Specifically, (a) of FIG. 3 is a top view showing the configuration of the closing member 300 shown in (b) of FIG. 2 and its surroundings when viewed from the positive direction of the Z axis. b) is a cross-sectional view showing a cross-section of the configuration of FIG.

As shown in FIG. 3 , the closing member 300 has a body portion 301 and a pair of extension portions 302 . The main body portion 301 is the main body portion of the closing member 300 located at the central portion of the closing member 300 in the Y-axis direction. The body portion 301 is arranged in the positive direction of the Z axis of the liquid port 122 , abuts on the lid 120 while covering the entire liquid port 122 , and is joined to the lid 120 to close the liquid port 122 . In the present embodiment, the body portion 301 is a square plate-like portion when viewed from the Z-axis direction.

The pair of extending portions 302 are plate-like portions located at both ends of the closing member 300 in the Y-axis direction, and extend from the body portion 301 to both sides in the Y-axis direction. The pair of extending portions 302 extends (projects) from the body portion 301 toward the pair of long side surfaces 101 of the container 100, and when the closing member 300 is joined to the lid 120, the closing member 300 is attached to the lid 120. It is used as a part that is pressed and fixed (temporarily fixed). In the present embodiment, the pair of extension portions 302 are protrusions that protrude from the main body portion 301 toward both sides in the Y-axis direction in a semicircular shape, and have the same shape (on the XZ plane through the center of the main body portion 301). symmetrical shape with respect to a parallel plane). That is, the extension portion 302 in the positive Y-axis direction protrudes in the positive Y-axis direction in a semicircular shape from the end of the main body portion 301 in the positive Y-axis direction. It protrudes in a semicircular shape from the end of 301 in the negative direction of the Y axis toward the negative direction of the Y axis.

In this manner, the extending portion 302 has a shape in which the width in the X-axis direction decreases as the distance from the main body portion 301 increases. That is, the extending portion 302 has a smaller width in the X-axis direction than the body portion 301 at the Y-axis direction end. For this reason, the blocking member 300 has an end portion in the Y-axis direction (the third direction that intersects the first direction and the second direction) whose length in the X-axis direction (first direction) is ) in the X-axis direction (first direction).

Furthermore, since the extending portions 302 protrude from both ends of the square-shaped body portion 301 in the Y-axis direction, the length of the closing member 300 in the Y-axis direction (third direction) is reduced in the X-axis direction (first direction). Since the liquid port 122 has a circular shape, the closing member 300 is such that the distance between the liquid port 122 and the Y-axis direction (third direction) edge on both sides in the Y-axis direction (third direction) is equal to the X-axis direction ( larger than the distance between the edge in the X-axis direction (first direction) and the liquid port 122 on at least one side in the first direction). In the present embodiment, the closing member 300 is such that the distance between the Y-axis direction (third direction) edge on both sides in the Y-axis direction (third direction) and the liquid port 122 is is greater than the distance between the edges in the X-axis direction (first direction) on both sides of the liquid port 122 .

For example, as shown in (a) of FIG. 3, for the portion of the closing member 300 in the positive direction of the Y axis, the distance between the edge of the closing member 300 in the Y axis direction and the liquid port 122 (the distance from the liquid port 122 to the Y axis directional protrusion amount) is defined as the first distance A1. The first distance A1 is, for example, a position P1 at the intersection of a line passing through the center of the liquid port 122 and parallel to the Y-axis direction and the edge of the extended portion 302 in the positive direction of the Y-axis, and the center of the liquid port 122. It is the distance between the position P2 of the intersection of the line parallel to the Y-axis direction and the edge of the liquid port 122 in the positive direction of the Y-axis. The first distance A2 of the portion of the closing member 300 in the negative direction of the Y axis can be similarly defined.

Similarly, for the portion of the blocking member 300 in the positive direction of the X axis, the distance between the X-axis direction edge of the blocking member 300 and the liquid port 122 (the amount of protrusion in the X-axis direction from the liquid port 122) is defined as the second distance Define B1. The second distance B1 is, for example, X It is the distance between the position Q2 of the intersection of the line parallel to the axial direction and the edge of the liquid port 122 in the positive direction of the X-axis. The second distance B2 of the portion of the closing member 300 in the negative direction of the X axis can be similarly defined.

In the above definition, the closing member 300 has at least one of the first distances A1 and A2, which are the first distances on both sides in the Y-axis direction, and the second distances B1 and B2, which are the second distances on at least one side in the X-axis direction. bigger than In the present embodiment, both the first distances A1 and A2 on both sides in the Y-axis direction of the closing member 300 are greater than both the second distances B1 and B2 on both sides in the X-axis direction.

The closing member 300 is positioned closer to the liquid port 122 than the center position in the Y-axis direction (third direction) between the edge in the Y-axis direction (third direction) and the liquid port 122, and closes the lid 120 (wall part). That is, the closing member 300 is joined to the lid 120 at a position closer to the liquid port 122 than the center position in the Y-axis direction at the portion protruding from the liquid port 122 in the Y-axis direction. For example, the closing member 300 is positioned closer to the liquid port 122 than the central position P3 in the Y-axis direction between the position P1 of the edge in the Y-axis direction and the position P2 of the edge of the liquid port 122 in the positive direction of the Y-axis. is joined to the lid body 120 at a position close to . That is, the closing member 300 is joined to the lid body 120 between the position P2 and the central position P3 between the positions P1 and P2. The same applies to the portion of the blocking member 300 in the negative Y-axis direction. In this embodiment, the main body portion 301 of the closing member 300 is joined to the lid body 120 .

Specifically, the closing member 300 is placed on the lid 120 while the closing member 300 is in contact with the lid 120 . Then, the body portion 301 of the closing member 300 is joined to the lid body 120 . For example, a laser beam is irradiated from the positive direction of the Z-axis toward a position surrounding the liquid port 122 in the main body 301, and the main body 301 and the lid 120 are laser welded (penetration welded). As a result, the main body 301 and the lid 120 are formed with a welded portion 400 having a substantially annular shape when viewed from the Z-axis direction so as to surround the liquid port 122 . The joint portion 400 is a melted portion obtained by melting the body portion 301 of the closing member 300 and the lid body 120 by laser welding. Note that the joint portion 400 may be a portion joined by a method other than laser welding, such as resistance welding or ultrasonic joining. In the present embodiment, since the blocking member 300 is longer in the Y-axis direction than in the X-axis direction, the joint portion 400 has an elliptical ring shape that is slightly longer in the Y-axis direction than in the X-axis direction. An annular shape having the same length in the X-axis direction and the Y-axis direction may be used, or another annular shape may be used. The joints 400 may be discretely formed instead of annular.

The closing member 300 does not have a shaft portion that is inserted into the liquid port 122 and fitted (press-fitted) into the liquid port 122 . That is, the closing member 300 is arranged in the Z-axis positive direction of the lid 120 (wall) without being fitted with the lid 120 (wall), and is joined to the lid 120 (wall) to The mouth 122 is closed.

[3 Explanation of effects]
As described above, according to the energy storage device 10 according to the embodiment of the present invention, the lid 120 (wall portion) of the container 100 extending in the X-axis direction (first direction) does not fit. A closing member 300 joined to the lid 120 is provided. The closing member 300 has a larger distance between the edge and the liquid port 122 on both sides in the Y-axis direction (third direction) than the distance between the edge and the liquid port 122 on at least one side in the X-axis direction. By joining the closing member 300 to the lid 120 without engaging with the lid 120 in this manner, the lid 120 and the closing member 300 are not deformed when the closing member 300 is joined to the lid 120. can be suppressed, and joint failure can be suppressed. In addition, since the electrode terminal 200 or the gas discharge valve 121 or the like is arranged between the closing member 300 and the short side of the lid 120 (the side on the short side 102 side), Access to the closure member 300 is difficult. Therefore, when joining the closing member 300 to the lid 120 , it is difficult to fix (temporarily fix) the closing member 300 to the lid 120 from the short side of the lid 120 . On the other hand, it is easy to access the closing member 300 from the long side of the lid 120 (long side 101 side), and the closing member 300 is easily fixed to the lid 120 from the long side of the lid 120 ( temporary fixation). Therefore, the distance between the edge of the closing member 300 and the liquid port 122 on both sides in the Y-axis direction (the long side of the lid 120) is at least one side in the X-axis direction (the short side of the lid 120). , and the distance between the liquid port 122 and the edge thereof. Thereby, the closing member 300 can be easily accessed from both long sides of the lid 120 , and the closing member 300 can be temporarily fixed to the lid 120 from both long sides of the lid 120 . Therefore, when the closing member 300 is joined to the lid 120 , the closing member 300 can be easily and stably temporarily fixed to the lid 120 . There is no need to temporarily fix the closing member 300 to the lid 120 by temporary welding or the like. Therefore, the closure member 300 can be easily and stably temporarily fixed to the lid member 120 while suppressing the occurrence of defective joining when the closure member 300 is joined to the lid member 120 . Easy to join.

If the size of the closing member 300 arranged on the lid 120 of the container 100 is too large, it may cause problems. In order to temporarily fix the closing member 300 to the lid 120, the distance between the edge and the liquid port 122 in the Y-axis direction should be large. distance can be reduced. For this reason, the closing member 300 is formed so that the distance between the edge on both sides in the Y-axis direction and the liquid port 122 is larger than the distance between the edge on both sides in the X-axis direction and the liquid port 122 . As a result, it is possible to easily and stably temporarily fix the closing member 300 to the lid 120 from both sides of the lid 120 in the Y-axis direction while suppressing problems caused by the size of the closing member 300 becoming too large. .

By making the length of the closing member 300 in the Y-axis direction longer than the length in the X-axis direction, the distance between the edge in the Y-axis direction and the liquid port 122 becomes equal to the distance between the edge in the X-axis direction and the liquid port 122 . A configuration that is larger than the distance can be easily realized. As a result, the closing member 300 can be easily and stably temporarily fixed to the lid 120 , so that the closing member 300 can be easily joined to the container 100 .

If the size of the closing member 300 arranged on the lid 120 of the container 100 is too large, it may cause problems. In addition, the ends of the closing member 300 in the Y-axis direction need only be of a size that allows the closing member 300 to be temporarily fixed to the lid 120 . Length (width) can be shortened. For this reason, the closing member 300 is formed such that the length (width) in the X-axis direction of the ends in the Y-axis direction is shorter than the length (width) in the X-axis direction of the central portion in the Y-axis direction. As a result, it is possible to easily and stably temporarily fix the closing member 300 to the lid 120 from both sides of the lid 120 in the Y-axis direction while suppressing problems caused by the size of the closing member 300 becoming too large. . Further, by making the ends of the closing member 300 in the Y-axis direction shorter in width than the central portion, the closing member 300 can also serve as a mark for the temporarily fixed portion.

By joining the closing member 300 to the lid 120 at a position closer to the liquid port 122 than the center position in the Y-axis direction between the edge in the Y-axis direction and the liquid port 122, the closing member 300 can be removed at the time of joining. The end of the closing member 300 for temporarily fixing to the lid 120 can be widened. As a result, the closing member 300 can be easily and stably temporarily fixed to the lid 120 , so that the closing member 300 can be easily joined to the container 100 .

[4 Description of modified example]
(Modification 1)
Next, Modification 1 of the above embodiment will be described. 4A to 4C are top views showing the configuration of closing members 310 to 330 according to Modification 1 of the present embodiment. Specifically, FIGS. 4A to 4C are diagrams corresponding to (a) of FIG.

As shown in FIGS. 4A to 4C, in this modification, blocking members 310 to 330 are arranged in place of the blocking member 300 in the above embodiment. Other configurations of this modified example are the same as those of the above-described embodiment, so detailed description thereof will be omitted.

As shown in FIG. 4A, the closing member 310 includes a main body portion 311 that is joined to the lid 120 and closes the liquid port 122, and a main body portion 311 on both sides of the main body portion 311 in the Y-axis direction. and a pair of extended extensions 312 . The body portion 311 and the pair of extension portions 312 have a smaller width in the X-axis direction than the body portion 301 and the pair of extension portions 302 in the above embodiment. Specifically, the closing member 310 has an elliptical shape when viewed from the Z-axis direction.

As shown in FIG. 4B, the closing member 320 includes a main body portion 321 that is joined to the lid 120 and closes the liquid port 122, and a main body portion 321 on both sides of the main body portion 321 in the Y-axis direction, similarly to the closing member 300 in the above embodiment. and a pair of extended extension portions 322 . The body portion 321 has a substantially circular shape (specifically, an elliptical shape that is slightly longer in the Y-axis direction than in the X-axis direction) when viewed from the Z-axis direction. The extending portion 322 has a rectangular shape (square or rectangular shape) with a smaller width in the X-axis direction than the central portion of the body portion 321 in the Y-axis direction when viewed from the Z-axis direction. Note that the body portion 321 may have a circular shape, an elliptical shape that is slightly shorter in the Y-axis direction than in the X-axis direction, an oval shape, a rectangular shape, or the like when viewed from the Z-axis direction.

As shown in FIG. 4C, similarly to the closing member 300 in the above-described embodiment, the closing member 330 includes a main body portion 331 that is joined to the lid 120 and closes the liquid port 122, and on both sides of the main body portion 331 in the Y-axis direction. and a pair of extension portions 332 that are extended. Specifically, the closing member 330 has a rectangular shape (rectangular shape) when viewed from the Z-axis direction.

As a result, the blocking members 310 to 330 are longer in the Y-axis direction than in the X-axis direction, similarly to the blocking member 300 in the above embodiment. That is, the distance between the Y-axis direction edges on both sides in the Y-axis direction and the liquid ports 122 of the closing members 310 to 330 is greater than the distance between the X-axis direction edges on both sides in the X-axis direction and the liquid ports 122. is also big. The closing members 310 to 330 are joined to the lid body 120 at positions closer to the liquid port 122 than the center position in the Y-axis direction between the edge in the Y-axis direction and the liquid port 122 . The closing members 310 to 330 are arranged in the positive direction of the Z axis of the lid 120 without being fitted with the lid 120 , and are joined to the lid 120 to close the liquid port 122 . In the closing members 310 and 320, the length in the X-axis direction of the end portions in the Y-axis direction is shorter than the length in the X-axis direction of the central portion in the Y-axis direction.

As described above, according to the power storage device according to this modification, the same effects as those of the above-described embodiment can be obtained. As in this modification, the closing member can have various shapes when viewed from the Z-axis direction.

(Modification 2)
Next, Modification 2 of the above embodiment will be described. FIG. 5 is a cross-sectional view showing the configuration of a closing member 340 according to Modification 2 of the present embodiment. Specifically, FIG. 5 is a diagram corresponding to (b) of FIG.

As shown in FIG. 5, in this modified example, a closing member 340 is arranged instead of the closing member 300 in the above embodiment. The closing member 340 has the main body portion 301 and the pair of extension portions 302 of the closing member 300 in the above embodiment, but the main body portion 301 is provided with the shaft portion 341 and the concave portion 342 . there is Other configurations of this modified example are the same as those of the above-described embodiment, so detailed description thereof will be omitted.

The shaft portion 341 is a projecting portion arranged to project from the body portion 301 and inserted into the liquid port 122 of the lid 120 . The shaft portion 341 is a columnar portion that is arranged at the central position of the main body portion 301 when viewed from the Z-axis direction, and is arranged to extend from the central position in the negative Z-axis direction. The shaft portion 341 has an outer peripheral shape (outer diameter) smaller than an inner peripheral shape (inner diameter) of the liquid port 122 when viewed from the Z-axis direction, and is inserted into the liquid port 122 without being fitted (press-fitted). be. The shaft portion 341 may be a columnar portion other than the columnar shape, or may be tapered shape in which the tip gradually becomes thinner.

The concave portion 342 is a substantially conical concave portion that is arranged at the center position of the outer surface (surface in the positive Z-axis direction) of the main body portion 301 and is concave in the negative Z-axis direction. The concave portion 342 is arranged in the positive Z-axis direction of the shaft portion 341 , that is, in the positive Z-axis direction of the liquid port 122 . The shape of the recess 342 is not particularly limited.

As described above, according to the power storage device according to this modification, the same effects as those of the above-described embodiment can be obtained. In particular, in this modified example, since the closing member 340 has the shaft portion 341 that is inserted without being fitted into the liquid port 122, the lid body 120 and the closing member 340 are not deformed due to fitting. The closure member 340 can be easily positioned relative to 120 . Also, the recess 342 can be used as a mark when joining the closing member 340 to the lid 120 . That is, since the position of the closing member 340 can be grasped by the concave portion 342 , the closing member 340 can be arranged at an accurate position on the lid 120 and joined to the lid 120 . As a result, when the closing member 340 is joined to the lid 120 , the closing member 340 can be easily arranged on the lid 120 , so that the closing member 340 can be easily joined to the container 100 .

(Modification 3)
Next, Modification 3 of the above embodiment will be described. FIG. 6 is a cross-sectional view showing the configuration of a closing member 350 according to Modification 3 of the present embodiment. Specifically, FIG. 6 is a diagram corresponding to (b) of FIG.

As shown in FIG. 6, in this modified example, a closing member 350 is arranged instead of the closing member 300 in the above embodiment. The closing member 350 has the main body portion 301 and the pair of extended portions 302 of the closing member 300 in the above-described embodiment, and the main body portion 301 is provided with a concave portion 351 . Other configurations of this modified example are the same as those of the above-described embodiment, so detailed description thereof will be omitted.

The recessed portion 351 is an annular recessed portion when viewed from the Z-axis direction, in which the surface of the main body portion 301 in the positive Z-axis direction is recessed in the negative Z-axis direction in a rectangular shape. . That is, the body portion 301 and the lid body 120 are joined at the recess 351 . For example, a laser beam is irradiated from the Z-axis positive direction toward the concave portion 351 to laser weld (penetration weld) the main body portion 301 and the lid body 120 . As a result, the main body 301 and the lid 120 are formed along the recess 351 so as to surround the liquid port 122, and the joint 400, which is a substantially annular welded portion when viewed from the Z-axis direction, is formed. be done.

As described above, according to the power storage device according to this modification, the same effects as those of the above-described embodiment can be obtained. In particular, in this modified example, by forming the concave portion 351 in the main body portion 301, the thickness of the joining (welding) target portion of the main body portion 301 is reduced, so that the main body portion 301 can be easily joined (welded) to the lid body 120. can.

(Other modifications)
As described above, the storage device according to the embodiment of the present invention (including modifications thereof; the same shall apply hereinafter), but the present invention is not limited to this embodiment. The embodiments disclosed this time are exemplifications in all respects, and the scope of the present invention includes all modifications within the meaning and range of equivalents to the scope of the claims.

For example, in the above embodiment, the liquid port 122 is formed in the lid 120 of the container 100 and the closing member is joined to the lid 120 . However, the liquid port 122 may be formed in the container body 110 of the container 100 and the closure member may be joined to the container body 110 .

In the above-described embodiment, the closing member has the distance between the Y-axis direction edge and the liquid port 122 on both sides in the Y-axis direction, and the distance between the X-axis direction edge and the liquid port 122 on both sides in the X-axis direction. was set to be larger than However, in the closing member, the distance between the Y-axis direction edge and the liquid port 122 on either side or both sides in the Y-axis direction is equal to the distance between the X-axis direction edge and the liquid port 122 on either side in the X-axis direction. 122 may be smaller.

In the above embodiment, the blocking member has a length in the Y-axis direction that is longer than a length in the X-axis direction. However, in the closing member, the distance between the Y-axis direction edge and the liquid port 122 on both sides in the Y-axis direction is longer than the distance between the X-axis direction edge and the liquid port 122 on at least one side in the X-axis direction. In a large configuration, the length in the X-axis direction may be longer than the length in the Y-axis direction. If the liquid port 122 has a shape that is long in the X-axis direction, it is conceivable that the closing member has a shape that is long in the X-axis direction.

In the above embodiment, the closing member is joined to the lid body 120 at a position closer to the liquid port 122 than the center position in the Y-axis direction between the edge in the Y-axis direction and the liquid port 122. . However, the closing member may be joined to the lid body 120 at a position farther from the liquid port 122 than the central position in the Y-axis direction. In other words, the joining portion 400 may be formed in the extending portion of the closing member instead of the main portion.

In the above embodiment, the pair of extended portions of the closing member have the same shape (plane-symmetrical shape), but they may have different shapes. In other words, the closing member may have an asymmetric shape in the X-axis direction or the Y-axis direction, or a non-rotationally symmetric shape.

Forms constructed by arbitrarily combining the constituent elements included in the above embodiments and modifications thereof are also included within the scope of the present invention.

The present invention can be realized not only as such an electric storage element, but also as a combination of a container and a closing member.

INDUSTRIAL APPLICABILITY The present invention can be applied to storage elements such as lithium ion secondary batteries.

10 storage element 100 container 101 long side 102 short side 103 bottom 110 container body 120 lid 121 gas discharge valve 122 liquid port 200 electrode terminal 210 upper gasket 300, 310, 320, 330, 340, 350 closing member 301, 311, 321 , 331 body portion 302, 312, 322, 332 extension portion 341 shaft portion 342, 351 recess portion 400 joint portion

Claims (6)

a container having a wall extending in a first direction and having a liquid port for the electrolytic solution;
a closing member that is arranged in a second direction that intersects with the first direction of the wall portion without being fitted to the wall portion and that is joined to the wall portion to close the liquid port;
In the closing member, the distance between the edge in the third direction and the liquid port on both sides of the third direction intersecting the first direction and the second direction is the third distance on at least one side of the first direction. A power storage element that is greater than the distance between the edge in one direction and the liquid port. In the closing member, the distance between the third direction edge and the liquid port on both sides in the third direction is greater than the distance between the first direction edge and the liquid port on both sides in the first direction. is large. The power storage device according to claim 1 or 2, wherein the closing member has a length in the third direction that is longer than a length in the first direction. 4. The closure member according to any one of claims 1 to 3, wherein the length of the ends in the third direction in the first direction is shorter than the length of the central portion in the third direction in the first direction. The storage device described. The closing member is joined to the wall portion at a position closer to the liquid port than the center position in the third direction between the edge in the third direction and the liquid port. The electricity storage device according to any one of items 1 to 3. The electric storage element according to any one of claims 1 to 5, wherein the closing member has a shaft portion that is inserted without being fitted into the liquid port.

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