JP2020184517A - Accumulation device valve structure - Google Patents

Abstract

To provide an accumulation device valve structure to be easily attached to a container.SOLUTION: A valve structure to be attached to a container is provided. The valve structure is for an accumulation device and comprises: a casing in which a passage is formed that discharges gas produced inside the container to the outside of the container; and a valve mechanism which is contained inside the casing and allows the gas to pass to the outside of the container via the passage when the internal pressure of the container rises because of the gas produced inside the container. The casing includes a first plane and a second plane which is parallel to the first plane.SELECTED DRAWING: Figure 3

Description

The present invention relates to a valve structure for a power storage device and a power storage device including the valve structure.

Patent Document 1 discloses a pouch-type lithium secondary battery. In this battery, a valve structure for venting gas is sandwiched between peripheral seals formed along the peripheral edge of a bag accommodating a battery element. This valve structure can suppress the shape of the bag from being deformed by discharging the gas generated in the bag.

Japanese Unexamined Patent Publication No. 2016-31934

Attachment of the valve structure to the peripheral seal portion as in Patent Document 1 is typically performed by sandwiching the valve structure with the packaging material constituting the bag and heat-sealing the valve structure together with the packaging material. .. Further, typically, the valve structure is conveyed to a processing position where heat sealing is performed in a state of being gripped by a gripping tool or the like included in the jig, and is fixed at the processing position during heat sealing. However, in the valve structure of Patent Document 1, the portion protruding from the peripheral seal portion to the outside of the bag is cylindrical. This makes it difficult to firmly grip the valve structure, so that, for example, it may be difficult to convey the valve structure to the machining position or fix it at the machining position, and thus the container of the valve structure. Can be difficult to attach to.

An object of the present invention is to provide a valve structure for a power storage device that can be easily attached to a container, and a power storage device including the valve structure.

The valve structure for a power storage device according to the first aspect of the present invention is a valve structure attached to a container, and has a casing formed with a passage for discharging gas generated inside the container to the outside of the container. A valve mechanism that is held in the casing and allows the gas to pass to the outside of the container through the passage when the internal pressure of the container rises due to the gas generated inside the container. Be prepared. The casing includes a first plane and a second plane parallel to the first plane.

The valve structure for a power storage device according to the second aspect of the present invention is the valve structure according to the first aspect, and the casing has a first air passage included in the passage, and inside the container. It includes a first portion fixed to the container so that the generated gas flows into the first air passage.

The valve structure for a power storage device according to a third aspect of the present invention is a valve structure according to a second aspect, and the casing is included in the passage and is on the outer side of the container with respect to the first air passage. Has a second vent located in, holds the valve mechanism, and has a third vent included in the passage and located on the outer side of the container with respect to the first vent. Further includes the first plane and a third portion including the second plane.

The valve structure for a power storage device according to a fourth aspect of the present invention is a valve structure according to a third aspect, and the third vent is located on the inner side of the container with respect to the second vent. ..

The valve structure for a power storage device according to a fifth aspect of the present invention is a valve structure according to any one of the second to fourth aspects, and the first portion is in the direction in which the first air passage extends. When viewed along, it is non-circular.

The valve structure for a power storage device according to the sixth aspect of the present invention is a valve structure according to any one of the second to fifth aspects, and the first portion is in the direction in which the first air passage extends. When viewed along, it has a first wing-shaped portion formed thinner toward the first direction from the central portion and a second wing-shaped portion formed thinner toward the second direction opposite to the first direction. ..

The valve structure for a power storage device according to the seventh aspect of the present invention is the valve structure according to the sixth aspect, and the first plane and the second plane are parallel to the first direction and the second direction. Or it is vertical.

The power storage device according to the eighth aspect of the present invention is made of a packaging material, and is housed in a container having an internal space, a peripheral seal portion defining the peripheral edge of the internal space, and an internal space of the container. It includes a battery element and a valve structure attached to the peripheral seal portion. The valve structure is formed by a casing in which a passage for discharging gas generated inside the container to the outside of the container is formed, and the gas held in the casing and generated inside the container. It includes a valve mechanism for passing the gas to the outside of the container through the passage when the internal pressure of the container rises. The casing includes a first plane and a second plane parallel to the first plane.

The power storage device according to the ninth aspect of the present invention is the power storage device according to the eighth aspect, and the first plane and the second plane are parallel or perpendicular to the direction in which the peripheral seal portion extends.

According to the present invention, the casing of the valve structure for a power storage device includes a pair of planes (first plane and second plane) parallel to each other. Such a pair of planes makes it easier to grip the valve structure, which allows, for example, the valve structure to be easily transported to the machining position or easily fixed at the machining position. As a result, the valve structure can be easily attached to the container.

The plan view of the power storage device including the valve structure for the power storage device according to the embodiment of the present invention. FIG. 1 is a sectional view taken along line II-II of FIG. Top view of the valve structure. The figure which looked at the valve structure from the rear side. The figure which looked at the valve structure from the front side. FIG. 4 is a sectional view taken along line VI-VI of FIG. FIG. 3 is a sectional view taken along line VII-VII of FIG. The figure explaining the method of attaching a valve structure to a container. Another figure illustrating how the valve structure is attached to the container. Yet another diagram illustrating how the valve structure is attached to the container. Sectional drawing of the valve structure which concerns on a certain modification. The figure which shows the breaking valve included in the valve structure which concerns on a certain modification. The figure which looked at the valve structure which concerns on another modification from the rear surface side. The plan view of the valve structure which concerns on still another modification. The figure which looked at the valve structure which concerns on still another modified example from the rear surface side. The figure which looked at the valve structure which concerns on still another modified example from the rear surface side. The figure which looked at the valve structure which concerns on still another modified example from the rear surface side. FIG. 3 is a cross-sectional view of a valve structure according to still another modification. FIG. 3 is a cross-sectional view of a valve structure according to still another modification.

Hereinafter, a valve structure for a power storage device according to an embodiment of the present invention and a power storage device including the valve structure will be described with reference to the drawings.

<1. Overall configuration of power storage device>
FIG. 1 shows a plan view of the power storage device 1 according to the present embodiment. FIG. 2 is a sectional view taken along line II-II of FIG. In these figures, the parts that are originally invisible from the outside are partially shown by dotted lines for reference. Hereinafter, for convenience of explanation, unless otherwise specified, the vertical direction of FIG. 1 is referred to as "front and back", the horizontal direction is referred to as "left and right", and the vertical direction of FIG. 2 is referred to as "up and down". However, the orientation of the power storage device 1 when used is not limited to this.

The power storage device 1 includes an accommodating body 101 and a battery element 400 accommodated therein. The container 101 includes a container 100, and a tab 300 and a tab film 310 attached to the container 100. The battery element 400 is housed in the internal space S1 of the container 100.

The container 100 is composed of packaging materials 110 and 120. In the outer peripheral portion of the container 100 in a plan view, the packaging materials 110 and 120 are heat-sealed and fused to each other, whereby the peripheral seal portion 130 is formed. Then, the peripheral space S1 of the container 100 that is shielded from the external space is formed by the peripheral seal portion 130. The peripheral edge sealing portion 130 defines the peripheral edge of the internal space S1 of the container 100. As the mode of heat sealing referred to here, modes such as heat welding from a heat source and ultrasonic welding are assumed. In any case, the peripheral seal portion 130 means a portion where the packaging materials 110 and 120 are fused and integrated.

The packaging materials 110 and 120 are made of, for example, a resin molded product or a film. The resin molded product referred to here can be manufactured by a method such as injection molding, compressed air molding, vacuum forming, blow molding, or the like, and in-mold molding may be performed in order to impart designability and functionality. The type of resin may be polyolefin, polyester, nylon, ABS, or the like. Further, the film referred to here is, for example, a plastic film that can be manufactured by a method such as an inflation method or a T-die method, or a film obtained by laminating these plastic films on a metal foil. Further, the film referred to here may or may not be stretched, and may be a single-layer film or a laminated film. Further, the laminated film referred to here may be produced by a coating method, a plurality of films bonded by an adhesive or the like, or may be produced by a multilayer extrusion method.

As described above, the packaging materials 110 and 120 can be variously composed, but in the present embodiment, they are composed of a laminated film. The laminated film can be a laminated body in which a base material layer, a barrier layer and a thermosetting resin layer are laminated. The base material layer functions as a base material for the packaging materials 110 and 120, and is typically a resin layer that forms the outer layer side of the container 100 and has an insulating property. The barrier layer has a function of improving the strength of the packaging materials 110 and 120 and also preventing at least moisture or the like from entering the power storage device 1, and is typically a metal layer made of an aluminum alloy or the like. The thermosetting resin layer is typically made of a thermosetting resin such as polyolefin, and forms the innermost layer of the container 100.

The shape of the container 100 is not particularly limited, and may be, for example, a bag shape (pouch shape). The bag shape referred to here may be a three-way seal type, a four-way seal type, a pillow type, a gusset type, or the like. However, the container 100 of the present embodiment has the shape as shown in FIG. 2, and the packaging material 110 molded in a tray shape and the packaging material 120 also molded in a tray shape and superposed on the packaging material 110. Is manufactured by heat-sealing along the outer peripheral portion in a plan view. The packaging material 110 includes an annular flange portion 114 corresponding to an outer peripheral portion in a plan view, and a molding portion 112 that is continuous with the inner edge of the flange portion 114 and bulges downward from the flange portion 114. Similarly, the packaging material 120 includes an annular flange portion 124 corresponding to an outer peripheral portion in a plan view, and a molded portion 122 that is continuous with the inner edge of the flange portion 124 and bulges upward from the flange portion 124. The packaging material 110 and the packaging material 120 are superposed so that the molded portions 112 and 122 respectively bulge in opposite directions. In this state, the flange portion 114 of the packaging material 110 and the flange portion 124 of the packaging material 120 are heat-sealed so as to be integrated to form the peripheral seal portion 130. The peripheral edge sealing portion 130 extends over the entire outer circumference of the container 100 and is formed in an annular shape. One of the packaging material 110 and the packaging material 120 may be in the form of a sheet.

The battery element 400 is, for example, a power storage member such as a lithium ion battery (secondary battery) or a capacitor, and contains an electrolytic solution. When an abnormality occurs in the battery element 400, gas may be generated in the internal space S1 of the container 100. Further, when the battery element 400 is a capacitor, gas may be generated in the internal space S1 of the container 100 due to a chemical reaction in the capacitor. Further, the power storage device 1 may be an all-solid-state battery, and in this case, the battery element 400 may contain a solid electrolyte capable of generating gas. For example, when the solid electrolyte is sulfide-based, hydrogen sulfide gas can be generated.

The tab 300 is a metal terminal used for input / output of electric power in the battery element 400. The tabs 300 are separately arranged at the left and right end portions of the peripheral edge seal portion 130 of the container 100, one of which constitutes a terminal on the positive electrode side and the other of which constitutes a terminal on the negative electrode side. One end of each tab 300 in the left-right direction is electrically connected to the electrode (positive electrode or negative electrode) of the battery element 400 in the internal space S1 of the container 100, and the other end is from the peripheral seal portion 130. It protrudes outward. The above-described form of the power storage device 1 is particularly preferable for use in an electric vehicle such as an electric vehicle or a hybrid vehicle in which a large number of power storage devices 1 are connected in series and used at a high voltage. The mounting positions of the two tabs 300 that form the terminals of the positive electrode and the negative electrode are not particularly limited, and may be arranged on the same side of the peripheral seal portion 130, for example.

The metal material constituting the tab 300 is, for example, aluminum, nickel, copper or the like. When the battery element 400 is a lithium ion battery, the tab 300 connected to the positive electrode is typically made of aluminum or the like, and the tab 300 connected to the negative electrode is typically made of copper, nickel or the like. It is composed.

The left tab 300 is sandwiched between the packaging materials 110 and 120 via the tab film 310 at the left end of the peripheral sealing portion 130. The tab 300 on the right side is also sandwiched between the packaging materials 110 and 120 via the tab film 310 at the right end portion of the peripheral sealing portion 130.

The tab film 310 is a so-called adhesive film, and is configured to adhere to both the packaging materials 110 and 120 and the tab 300 (metal). By passing through the tab film 310, even if the tab 300 and the innermost layers (thermosetting resin layers) of the packaging materials 110 and 120 are different materials, both can be fixed.

When gas is generated in the internal space S1 of the container 100 with the operation of the power storage device 1, the pressure in the internal space S1 gradually increases. If the pressure in the internal space S1 rises excessively, the container 100 may burst and the power storage device 1 may be destroyed. The accommodating body 101 includes a valve structure 200 as a mechanism for preventing such a situation. The valve structure 200 is a gas vent valve for adjusting the pressure in the internal space S1, and is attached to the peripheral seal portion 130 of the container 100. Hereinafter, the configuration of the valve structure 200 will be described in detail.

<2. Structure of valve structure>
FIG. 3 is a plan view of the valve structure 200. As shown in the figure, the valve structure 200 has a casing 201, and the casing 201 includes a first portion 10, a second portion 20, and a third portion 30. In the present embodiment, these portions 10 to 30 are continuous in the order from the inside to the outside of the container 100 (the direction from the back side to the front side) in the order of the first part 10, the third part 30, and the second part 20. And are placed. FIG. 4 is a view of the valve structure 200 viewed from the first portion 10 side (from the rear side), and FIG. 5 is a view of the valve structure 200 viewed from the second portion 20 side (from the front side). ..

6 is a sectional view taken along line VI-VI of FIG. 4, and FIG. 7 is a sectional view taken along line VII-VII of FIG. As shown in FIGS. 6 and 7, the valve structure 200 of the present embodiment is a check valve capable of repeatedly venting gas, and is particularly a ball spring type check valve. The valve structure 200 is a relief valve that switches between an open state and a closed state according to the pressure in the internal space S1. A passage L1 is formed inside the casing 201. The passage L1 has an inlet O1 facing the internal space S1 of the container 100 and an outlet O2 facing the external space. The passage L1 allows the internal space S1 of the container 100 to communicate with the external space in the open state of the valve structure 200, and the gas generated in the internal space S1 can be discharged to the outside of the container 100. The valve structure 200 is opened when the pressure in the internal space S1 rises due to the gas generated in the internal space S1. On the other hand, the valve structure 200 seals the internal space S1 from the external space in the closed state.

The first portion 10 is a portion for attaching the valve structure 200 to the container 100. The first portion 10 is heat-sealed together with the packaging materials 110 and 120 when the container 100 is molded. By this heat seal, the outer peripheral surface of the first portion 10 and the packaging materials 110 and 120 are fused and joined, and the first portion 10 is sandwiched between the packaging materials 110 and 120 to the peripheral seal portion 130. It is fixed (see FIG. 2).

The third portion 30 is arranged outside the peripheral seal portion 130 and is not sandwiched between the packaging materials 110 and 120 (see FIGS. 1 and 2). Further, the second portion 20 arranged further outside the third portion 30 is also arranged outside the peripheral edge sealing portion 130, and is not sandwiched between the packaging materials 110 and 120. As a result, the heat generated when the first portion 10 is attached to the container 100 by the heat seal reduces the possibility that various parts that are held in the second portion 20 and constitute the valve mechanism, which will be described later, are destroyed due to deformation or the like. To.

The first portion 10, the second portion 20, and the third portion 30 extend coaxially with each other and parallel to each other in the front-rear direction (including the case where they are substantially parallel; the same applies hereinafter). Here, the central axis common to these portions 10 to 30 is represented by reference numeral C1. The first portion 10 has a first vent passage A1, the second portion 20 has a second vent passage A2, and the third portion 30 has a third vent passage A3. These ventilation passages A1 to A3 also extend coaxially with each other and parallel to each other in the front-rear direction with the central axis C1 as the central axis. In the present embodiment, the inlet O1 and the outlet O2 are arranged not on the outer peripheral surface of the casing 201 but on the end surface in the front-rear direction. In particular, the central axis C1 extending linearly in the front-rear direction is the inlet O1 and the outlet O2. Pass through the center. Although not limited to this, the cross section of the ventilation passages A1 to A3 orthogonal to the central axis C1 is circular. The ventilation passages A1 to A3 communicate with each other and form the passage L1 as a whole. The third air passage A3 is arranged on the outer side of the container 100 from the first air passage A1, and the second air passage A2 is arranged on the outer side of the container 100 further than the third air passage A3. In other words, the third air passage A3 is arranged on the inner side of the container 100 than the second air passage A2, and the first air passage A1 is arranged on the inner side of the container 100 further than the third air passage A3. ..

As shown in FIGS. 4 and 5, the outer shape of the second portion 20 is generally a cylindrical shape with the central axis C1 as the central axis. On the other hand, as shown in FIG. 4, the outer shape of the third portion 30 has a shape in which a part of a cylinder with the central axis C1 as the central axis is cut out. More specifically, the outer shape of the third portion 30 is generally a plane having a central axis C1 as the central axis, cut out in a plane separated from the central axis C1 by a certain distance, and the plane with respect to the central axis C1. It has a shape that is further cut out on a plane that is symmetrical to the above. Therefore, the third portion 30 has a pair of planes D1 and D2. Hereinafter, the plane represented by D1 may be referred to as a first plane, and the plane represented by D2 may be referred to as a second plane. The first plane D1 and the second plane D2 are parallel to each other (including the case where they are substantially parallel; the same applies hereinafter). The first plane D1 and the second plane D2 are parallel to the extending direction of the central axis C1 (including a case where they are substantially parallel; the same applies hereinafter). Further, in the present embodiment, the first plane D1 and the second plane D2 are parallel to the direction in which the peripheral edge sealing portion 130 extends (including the case where they are substantially parallel; the same applies hereinafter). The outer peripheral surface of the third portion 30 is composed of a first plane D1 and a second plane D2, and curved surfaces D3 and D4 connecting these planes D1 and D2. Each of the curved surfaces D3 and D4 has an arc shape centered on the central axis C1 when viewed along the extending direction of the central axis C1 and overlaps the outer shape of the second portion 20. The second portion 20 as described above can be formed by cutting the outer peripheral surface of the cylindrical member so that a pair of planes D1 and D2 are formed.

As shown in FIG. 4, the first portion 10 has a non-circular outer shape when viewed along the extending direction of the central axis C1. More specifically, the first portion 10 has a first wing-shaped portion 41 formed thinner toward the left from the central portion in the left-right direction when viewed along the extending direction of the central axis C1 and to the right. It has a second wing-shaped portion 42 formed thinner toward the direction. Therefore, in the present embodiment, the first portion 10 becomes thicker as it approaches the central portion in the width direction (horizontal direction) of the power storage device 1, and becomes thinner as it approaches the end portion in the width direction (horizontal direction) of the power storage device 1. ..

In the present embodiment, the wing-shaped portions 41 and 42 provide a smooth curved surface on the outer peripheral surface of the first portion 10 in both the lower half covered with the packaging material 110 and the upper half covered with the packaging material 120, respectively. I'm drawing. Further, as compared with the case where the first portion 10 is formed in a cylindrical shape by the wing-shaped portions 41 and 42, for example, the peripheral seal portion 130 from the portion where the first portion 10 is not sandwiched to the peripheral seal portion 130 is the third. At the position where the portion 10 shifts to the sandwiched portion, the change in the thickness of the power storage device 1 in the vertical direction becomes smooth. As a result, since no excessive force is applied to the packaging materials 110 and 120 in the peripheral portion of the peripheral seal portion 130 at the position where the first portion 10 is attached, the first portion 10 is firmly fixed to the peripheral seal portion 130. can do.

As described above, in the present embodiment, the outer shapes of the first portion 10, the second portion 20, and the third portion 30 are assigned to the respective portions when viewed along the extending direction of the central axis C1. Each has a different shape depending on the above.

The second portion 20 holds the valve mechanism. The valve mechanism second vents the gas that has passed through the first air passage A1 and the third air passage A3 when the pressure in the internal space S1 rises due to the gas generated in the internal space S1 of the container 100. It is passed to the outside of the container 100 through the path A2. That is, the second portion 20 holds a portion having a main structure for exerting the function of the valve structure 200 as a gas vent valve. In the present embodiment, the spring 212, the ball 213, and the valve seat 214 as the valve mechanism are housed in the second ventilation passage A2 inside the second portion 20. An insertion portion 215 continuous with the third portion 30 is also housed in the second ventilation passage A2. These portions 212 to 215 are arranged in this order from the outlet O2 to the inlet O1 in the second air passage A2. In the present embodiment, the second portion 20, the valve seat 214, and the insertion portion 215 are configured as separate parts, but at least a part of them may be integrally configured. Further, in the present embodiment, as shown in FIGS. 6 and 7, the insertion portion 215 is integrally configured with the third portion 30 and the first portion 10, but at least a part thereof is configured as a separate component. May be done.

The valve seat 214 receives the ball 213 as a valve body urged from the outside by the spring 212, and at this time, the closed state of the valve structure 200 is formed. The spring 212 is a coil spring in the examples of FIGS. 6 and 7, but the spring 212 is not limited to this, and may be, for example, a leaf spring.

The first portion 10 is fixed to the peripheral edge sealing portion 130 so that the gas generated in the internal space S1 of the container 100 flows into the first ventilation passage A1. That is, the first air passage A1 inside the first portion 10 communicates with the internal space S1 of the container 100. Therefore, when the pressure in the internal space S1, that is, the pressure in the first air passage A1 and the third air passage A3 communicating with the first air passage A1 reaches a predetermined pressure, the pressure in the internal space S1 flows out from the internal space S1 and the first air passage A1 and the first air passage A1 3 The gas that has passed through the ventilation path A3 pushes the ball 213 toward the outlet O2. When the ball 213 is pressed and separated from the valve seat 214, the spring 212 is deformed, the ball 213 moves to the outlet O2 side, and the valve structure 200 is in an open state. In this open state, the gas generated in the internal space S1 flows out toward the outlet O2 through the gap formed between the ball 213 and the valve seat 214, and is discharged to the external space through the outlet O2. .. In this way, when the gas in the internal space S1 is discharged through the passage L1, the force for pressing the ball 213 toward the outlet O2 weakens, and the spring 212 urges the ball 213 toward the inlet O1 side. The power to do becomes greater. As a result, the shape of the spring 212 is restored, and the closed state of the valve structure 200 is formed again.

The valve structure 200 can prevent the air from entering the internal space S1 of the container 100 in the closed state. On the other hand, even in the open state, it is unlikely that the atmosphere will enter the internal space S1. This is because, in the open state, the pressure in the internal space S1 is maintained higher than or equivalent to the pressure in the external space. Therefore, the valve structure 200 can effectively prevent the ingress of the atmosphere into the container 100, and can prevent the battery element 400 from being deteriorated by the moisture or the like contained therein.

The material constituting each part of the valve structure 200 is not particularly limited. To give a preferred example, the ball 213 can be made of fluororesin and the valve seat 214 can be made of fluororubber. Further, the spring 212 may be made of a metal such as stainless steel, and the first portion 10, the second portion 20, the third portion 30 and the insertion portion 215 may be made of a metal such as an aluminum alloy, stainless steel, a steel plate, or titanium. Further, the first portion 10 may be composed of a material that directly adheres to the innermost layers of the packaging materials 110 and 120. For example, the first portion 10 can be made of a material having the same heat-sealing properties as the innermost layers of the packaging materials 110 and 120, for example, a resin such as polyolefin. If the first portion 10 cannot be made of the above materials due to heat resistance or the like, for example, if the first portion 10 is made of metal, the first portion 10 and the packaging materials 110 and 120 are the most suitable. These can be bonded via a film that can be bonded to both the inner layer.

The valve seat 214 and the insertion portion 215 can be adhered with an adhesive. The material of this adhesive is also not particularly limited, but a preferable example in which the valve seat 214 is made of fluororubber and the insertion portion 215 is made of a metal such as aluminum can be composed of an acid-modified polyolefin and an epoxy resin. .. Such an adhesive is superior in that it can suppress deterioration of the adhesive performance due to the electrolytic solution, as compared with the case where, for example, an adhesive made of a modified silicone resin is used. Further, from the viewpoint of preventing the opening of the valve structure 200, an adhesive can be appropriately applied to various other places. For example, an adhesive can be applied between the rear end face of the second portion 20 and the front end face of the third portion 30.

Further, it is preferable that the surface of the first portion 10 is coated with a corrosion inhibitor to form a corrosion preventive coating layer, particularly from the viewpoint of electrolytic solution resistance. This is especially true when the first portion 10 is made of a metal such as aluminum, but it can also be applied when the first portion 10 is made of another material. Such a coating can be applied by immersing the first portion 10 in a liquid of a corrosion inhibitor. As a result, a corrosion prevention coating layer can be formed on the outer surface of the first portion 10 and the inner surface facing the first air passage A1, corrosion of the outer surface by the released gas, and the first air passage A1. It is possible to prevent corrosion of the inner surface due to the gas passing through. Further, particularly from the viewpoint of electrolytic solution resistance, the same coating is applied not only to the first portion 10 but also to the surfaces of the third portion 30, the second portion 20 and the insertion portion 215 to form a corrosion prevention coating layer. You may. However, from the viewpoint of suppressing deterioration of the adhesive performance between the first portion 10 and the packaging materials 110 and 120 due to the electrolytic solution, it is meaningful to apply such a coating particularly to the first portion 10. The material of the corrosion inhibitor is not particularly limited, but an acid resistant one is preferable, and the corrosion inhibitor film layer can be formed by phosphoric acid chromate treatment or the like.

<3. How to install the valve structure>
Next, a method of attaching the valve structure 200 to the container 100 will be described. First, the packaging materials 110 and 120 are fixed to face each other by a fixture (not shown). Further, the valve structure 200 is gripped by the gripping tool 501 of the jig 500 (see FIG. 8A). At this time, the valve structure 200 is in such a manner that the gripping tool 501 firmly contacts the first plane D1 and the second plane D2 of the third portion 30 and the third portion 30 is firmly sandwiched by the gripping tool 501. Be grasped. In FIGS. 8A to 8C, the molded portions 112 and 122 of the packaging materials 110 and 120 are not particularly shown in order to focus on the description of the attachment of the valve structure 200, but the molded portions 112 and 122 are shown. It is appropriately formed before, during, or after mounting the valve structure 200.

In the above state, the jig 500 is driven, the valve structure 200 gripped by the gripping tool 501 moves, and the first portion 10 is inserted into the gaps between the packaging materials 110 and 120 facing each other (see FIG. 8B). ). At this time, the valve structure 200 is moved so that the third portion 30 does not enter the same gap. Therefore, the first portion 10 is sandwiched between the outer peripheral portions of the packaging materials 110 and 120. Further, at this time, the valve structure 200 is moved so that the portion of the packaging materials 110 and 120 that becomes the peripheral edge sealing portion 130 and the first plane D1 and the second plane D2 of the third portion 30 are parallel to each other. ..

In the above state, the pair of heated seal bars 600 sandwich the outer peripheral portions of the packaging materials 110 and 120 from the outside (see FIG. 8C). As a result, the outer peripheral portions of the packaging materials 110 and 120 receive heat from the seal bar 600 and are fused to form the peripheral seal portion 130. As described above, the valve structure 200 is fixed to the peripheral seal portion 130 so that only the first portion 10 of the valve structure 200 is sandwiched between the packaging materials 110 and 120. At this time, the wing-shaped portions 41 and 42 included in the first portion 10 are fixed so that the line connecting the sharp ends thereof is not inclined with respect to the extending direction (left-right direction) of the peripheral edge sealing portion 130. After that, the pair of seal bars 600 retracts to a predetermined position, and the gripping tool 501 releases the valve structure 200 and retracts to a predetermined position.

In the above steps, the gripping tool 501 can firmly grip the valve structure 200 by the pair of parallel first planes D1 and second plane D2. Therefore, the valve structure 200 can be accurately transported to a desired position with respect to the packaging materials 110 and 120. Further, during the heat sealing process, the valve structure 200 can be firmly fixed to the packaging materials 110 and 120 at a desired position. That is, the valve structure 200 can be accurately aligned with the container 100. The alignment referred to here includes adjusting the phase around the central axis C1 of the valve structure 200. That is, the angle around the central axis C1 of the first portion 10 with respect to the peripheral seal portion 130 of the container 100 can be accurately adjusted. According to the above configuration, the valve structure 200 can be easily attached to the container 100.

<4. Modification example>
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the following changes can be made. In addition, the gist of the following modified examples can be combined as appropriate.

<4-1>
The valve structure 200 of the above embodiment is a ball spring type, but is not limited to this, and may be, for example, a poppet type, a duck bill type, an umbrella type, a diaphragm type, or the like. Further, the valve structure 200 of the above embodiment is a check valve capable of repeatedly degassing, but may be a destructive valve capable of degassing only once. It may also include both a check valve and a break valve.

The break valve referred to in this modification can be configured in various ways. For example, as shown in FIG. 9A, the break valve can be configured by a thin plate or film 250 as a valve mechanism, in which the casing 201 is held so as to block the passage L1 in the valve structure 200. This destructive valve (hereinafter, the destructive valve is designated by the reference numeral 250) can be configured, for example, by attaching a laminate film to the casing 201 by heat sealing so as to cover the outlet O2. In this example, when the pressure in the internal space S1 of the container 100 rises, the laminated film, which is the breaking valve 250, is peeled off to open the valve. As another example, the breaking valve 250 may be a thin plate made of metal such as aluminum, and as shown in FIG. 9B, a notch 251 extending radially from the vicinity of the center thereof may be formed in the thin plate. The notch portion 251 does not penetrate the break valve 250 in the thickness direction, and is formed thinner than other portions. In this case, when the pressure in the internal space S1 of the container 100 rises, the breaking valve 250 can be opened by breaking the breaking valve 250 instead of dropping it from the casing 201.

<4-2>
The first plane D1 and the second plane D2 of the third portion 30 do not have to be parallel to the direction in which the peripheral edge sealing portion 130 extends, and can face various directions. However, from the viewpoint of workability when the valve structure 200 is attached to the container 100, it is either parallel to the extending direction (horizontal direction) of the peripheral seal portion 130 or vertical (substantially vertical) as shown in FIG. Including certain cases. The same shall apply hereinafter.).

<4-3>
In the above embodiment, the third portion 30 is arranged closer to the inner side of the container 100 than the second portion 20, but as shown in FIG. 11, the third portion 30 is arranged closer to the outer side of the container 100 than the second portion 20. May be good.

<4-4>
The shape of the first portion 10 is not limited to that described above. For example, the outer shape of the first portion 10 may be non-circular as shown in FIGS. 12A and 12B when viewed along the extending direction of the first air passage A1. Further, the outer shape of the first portion 10 may be circular or elliptical as shown in FIG. 12C when viewed along the extending direction of the first air passage A1. In the case of an elliptical shape, it is preferable that its long axis extends parallel to the left-right direction (including the case where it is substantially parallel). That is, the first portion 10 may have a cylindrical shape or an elliptical cylinder shape extending along the central axis C1.

<4-5>
The shape of the second portion 20 is not limited to that described above, and the outer shape of the second portion 20 may be non-circular when viewed along the extending direction of the central axis C1, for example, an elliptical shape. It may be a triangle, a quadrangle, or a polygon of pentagon or more.

<4-6>
The shape of the third portion 30 is not limited to that described above. For example, as long as the third portion 30 has a pair of planes D1 and D2 parallel to each other, the shape of the other portions is not particularly limited. For example, the curved surfaces D3 and D4 may also be flat, and the outer shape of the third portion 30 may be a quadrangle when viewed along the extending direction of the central axis C1. Alternatively, the outer shape of the third portion 30 may have a regular hexagonal shape or a regular octagonal shape when viewed along the extending direction of the central axis C1.

<4-7>
In the above embodiment, the first portion 10 fixed to the peripheral edge sealing portion 130, the second portion 20 holding the valve mechanism, and the third portion 30 including the pair of planes D1 and D2 extend in the direction in which the passage L1 extends. It was formed as an independent and separate site. However, the present invention is not limited to this embodiment, and for example, as shown in FIG. 13A, the second portion 20 may be omitted and the valve mechanism may be moved to the first portion 10. Alternatively, as shown in FIG. 13B, a pair of planes D1 and D2 may be formed on the outer surface of the second portion 20 holding the valve mechanism, and the third portion 30 may be omitted.

1 Power storage device 100 Container 110 Packaging material 120 Packaging material 130 Peripheral seal 101 Containment body 200 Valve structure 201 Casing 10 First part 20 Second part 30 Third part 400 Battery element 41 First wing-shaped part 42 Second wing-shaped part L1 Passage A1 1st air passage A2 2nd air passage A3 3rd air passage D1 1st plane D2 2nd plane O1 Inlet O2 Exit S1 Internal space

Claims (9)

A valve structure that can be attached to a container
A casing formed with a passage for discharging the gas generated inside the container to the outside of the container.
It is provided with a valve mechanism that is held in the casing and allows the gas to pass to the outside of the container through the passage when the internal pressure of the container rises due to the gas generated inside the container. ,
The casing includes a first plane and a second plane parallel to the first plane.
Valve structure for power storage device. The casing is
A first portion having a first vent included in the passage and being fixed to the container so that the gas generated inside the container flows into the first vent.
The valve structure for a power storage device according to claim 1. The casing is
A second portion included in the passage, having a second vent that is located on the outer side of the container with respect to the first vent, and holding the valve mechanism.
It has a third vent that is included in the passage and is located on the outer side of the container with respect to the first vent, and further includes the first plane and a third portion including the second plane.
The valve structure for a power storage device according to claim 2. The third vent is located on the inner side of the container with respect to the second vent.
The valve structure for a power storage device according to claim 3. The first portion is non-circular when viewed along the extending direction of the first air passage.
The valve structure for a power storage device according to any one of claims 2 to 4. The first portion has a first wing-shaped portion formed thinner from the central portion toward the first direction when viewed along the extending direction of the first air passage, and a second portion opposite to the first direction. It has a second wing-shaped portion that is formed thinner toward the direction.
The valve structure for a power storage device according to any one of claims 2 to 5. The first plane and the second plane are parallel or perpendicular to the first direction and the second direction.
The valve structure for a power storage device according to claim 6. A container made of a packaging material and having an internal space and a peripheral seal portion defining the peripheral edge of the internal space.
The battery element housed in the internal space of the container and
A power storage device including a valve structure attached to the peripheral seal portion.
The valve structure is
A casing formed with a passage for discharging the gas generated inside the container to the outside of the container.
Includes a valve mechanism that is held in the casing and allows the gas to pass to the outside of the container through the passage when the internal pressure of the container rises due to the gas generated inside the container. ,
The casing includes a first plane and a second plane parallel to the first plane.
Power storage device. The first plane and the second plane are parallel or perpendicular to the direction in which the peripheral seal portion extends.
The power storage device according to claim 8.