JP2022069082A - Gaskets and batteries - Google Patents

Abstract

[Problem] To provide a gasket that can suppress deformation of a sealing body even when the gasket is compressed by a protrusion. [Solution] A gasket 1 that is placed between a terminal and a sealing body of a battery, the gasket 1 has a cylindrical portion 1a and a flange portion 1b that is placed on one end face of the cylindrical portion, and satisfies 0.53A≦V1-V2≦A, where V1 is the volume of a sealed area defined by the side of the penetration portion of the sealing body, the main plane on the outer face side of the sealing body, the side of the terminal at the penetration portion, and the top face of the insulating member at the penetration portion, V2 is the volume of a corresponding sealed area of the gasket that corresponds to the sealed area, and A is the volume of a protrusion that is placed on at least one of the sealing body and the terminal to improve the sealability. [Selected Figure] Figure 1

Description

The present disclosure relates to gaskets and batteries.

A technique is known in which a gasket is interposed between a terminal and a sealing body to seal a battery. For example, in Patent Document 1, a square secondary battery including a battery can, a lid in which an external terminal is arranged and closes an opening of the battery can, and a gasket interposed between the lid and the lower surface of the external terminal. Is disclosed. Further, FIG. 7 of Patent Document 1 discloses that the lid 8 has an annular convex portion 85. Further, Patent Documents 2 and 3 also disclose a square secondary battery including a gasket interposed between a terminal and a lid.

Japanese Patent No. 6577998 Japanese Unexamined Patent Publication No. 2016-17397 Japanese Unexamined Patent Publication No. 2016-207510

As disclosed in Patent Document 1, by providing the convex portion (projection portion) on the lid (sealing body), the gasket is compressed when the terminal is installed, and the airtightness is improved. On the other hand, when the gasket is compressed by the protrusion, there is no escape place for the compressed meat, and a force is generated to push the penetrating portion of the sealing body open. Therefore, the sealing body may be deformed or in the state immediately before it. When the sealing body is deformed, the airtightness of the battery tends to decrease.

The present disclosure has been made in view of the above circumstances, and an object of the present invention is to provide a gasket capable of suppressing deformation of the sealing body even when the gasket is compressed by a protrusion.

In the present disclosure, it is a gasket arranged between a terminal and a sealing body in a battery, and has a tubular portion and a flange portion arranged on one end surface of the tubular portion, and the sealing body. The volume of the sealed region defined by the side surface of the penetrating portion, the main plane on the outer surface side of the sealing body, the side surface of the terminal in the penetrating portion, and the top surface of the insulating member in the penetrating portion is defined as V ₁ . When the volume of the sealing corresponding area of the gasket corresponding to the sealing area is V ₂ , and the volume of the protrusion arranged to enhance the sealing on at least one of the sealing body and the terminal is A, 0. Provided is a gasket that satisfies 53A ≦ V ₁ −V ₂ ≦ A.

According to the present disclosure, since V ₁ , V ₂ and A satisfy a predetermined relationship, it is possible to obtain a gasket capable of suppressing deformation of the sealing body even when the gasket is compressed by the protrusion. ..

Further, in the present disclosure, the power generation element, the current collecting member for collecting the power generation element, the exterior body for accommodating the power generation element and the current collection member, and the exterior body are sealed and penetrated. A sealing body having the above, a terminal arranged in the penetrating portion and electrically connected to the current collecting member, a gasket arranged between the terminal and the sealing body, and the sealing body and the current collecting member. A battery having an insulating member arranged between the two, the sealing body and at least one of the terminals have a protrusion for enhancing the airtightness, and the gasket has a tubular portion and the above. It has a flange portion arranged on one end surface of the tubular portion, and has a side surface of the penetration portion, a main plane on the outer surface side of the sealing body, a side surface of the terminal in the penetration portion, and a penetration portion. When the volume of the sealed region defined by the top surface of the insulating member is V ₁ , the volume of the sealed region of the gasket corresponding to the sealed region is V ₂ , and the volume of the protrusion is A. Provided is a battery satisfying 0.53A ≤ V ₁ -V ₂ ≤ A.

According to the present disclosure, since V ₁ , V ₂ and A satisfy a predetermined relationship, it is possible to obtain a battery capable of suppressing deformation of the sealing body even when the gasket is compressed by the protrusion. ..

The gasket in the present disclosure has an effect that deformation of the sealing body can be suppressed even when the gasket is compressed by the protrusion.

It is a schematic perspective view which illustrates the gasket in this disclosure. It is a schematic sectional drawing illustrating the battery in this disclosure. It is schematic cross-sectional view which illustrates the terminal structure in this disclosure. It is a schematic cross-sectional view illustrating the closed area in this disclosure. It is a schematic cross-sectional view illustrating the hermetically sealed area in this disclosure. It is a schematic cross-sectional view explaining the effect in this disclosure. It is a schematic sectional drawing illustrating the gasket in this disclosure. It is a schematic plan view which illustrates the gasket in this disclosure. It is a schematic perspective view which illustrates the sealing body in this disclosure. It is schematic cross-sectional view which illustrates the terminal structure in this disclosure.

Hereinafter, the present disclosure will be described in detail. Each figure shown below is schematically shown, and the size and shape of each part are exaggerated as appropriate for easy understanding. Further, in each figure, hatching showing a cross section of the member is omitted as appropriate. Further, in the present specification, when expressing the mode of arranging another member with respect to a certain member, when simply expressing "above" or "below", unless otherwise specified, it comes into contact with a certain member. As such, it includes both the case where another member is arranged directly above or directly below, and the case where another member is arranged above or below one member via another member.

FIG. 1 is a schematic perspective view illustrating the gasket in the present disclosure. The gasket 1 shown in FIGS. 1A and 1B has a tubular portion 1a, a flange portion 1b arranged on one end surface of the tubular portion 1a, and a side wall arranged along the outer edge of the flange portion 1b. It has a part 1c and. Note that FIG. 1A is a schematic perspective view when the side wall portion 1c is located in front and the tubular portion 1a is located in the back, while FIG. 1B is a cylinder. It is a schematic perspective view in the case where the shape portion 1a is located in front and the side wall portion 1c is located in the back. The tubular portion 1a has a hollow structure, and the shaft portion 6c of the terminal 6 described later is inserted into the hollow portion. Further, as shown in FIG. 1A, the flange portion 1b and the side wall portion 1c form a cage structure and can hold the external connection portion 6a of the terminal 6 described later.

FIG. 2 is a schematic cross-sectional view illustrating the battery in the present disclosure. The battery 10 shown in FIG. 2 houses a power generation element 2, a current collecting member 3 (positive side current collecting member 3A, negative value current collecting member 3B) for collecting power from the power generation element 2, a power generation element 2 and a current collecting member 3. Terminal 6 (positive electrode terminal 6A, which is arranged in the outer body 4 and the sealing body 5 which seals the outer body 4 and has the penetrating portion 5a, and is electrically connected to the current collector 3 It has a negative electrode terminal 6B), a gasket 1 arranged between the terminal 6 and the sealing body 5, and an insulating member 7 arranged between the sealing body 5 and the current collecting member 3.

FIG. 3 is a schematic cross-sectional view illustrating the terminal structure in the present disclosure. As shown in FIG. 3, the sealing body 5 has a penetrating portion 5a, and further has a protruding portion 5b arranged along the side surface 51 of the penetrating portion 5a. On the other hand, the terminal 6 has an external connection portion 6a for connecting to an external device (not shown), a current collector connection portion 6b connected to the current collector member 3, an external connection portion 6a, and a current collector connection portion 6b. It has a shaft portion 6c located between them and arranged in the penetration portion 5a. The shaft portion 6c is inserted into the cylindrical portion 1a of the gasket 1, the penetrating portion 7a of the insulating member 7, and the penetrating portion 3a of the current collecting member 3 arranged coaxially.

Further, FIG. 4 is a schematic cross-sectional view illustrating the sealed region in the present disclosure, and FIG. 5 is a schematic cross-sectional view illustrating the sealed region corresponding to the present disclosure. The details will be described later, but as shown in FIG. _{4, the volume of the closed region S1 is V 1 ,} and the volume of the protrusion 5b is A. Further, as shown in _FIG . 5B, the volume of the sealing corresponding region S2 of the gasket ₁ is defined as V2. In the present disclosure, V ₁ , V ₂ and A satisfy 0.53 A ≤ V ₁ -V ₂ ≤ A. V ₁ -V ₂ is the difference between the volume of the sealed region (reference volume required for the gasket) and the volume of the sealed region (actual volume of the gasket in the region corresponding to the sealed region). It is designed to be within a predetermined range based on the volume A of the protrusion.

Here, as described above, by providing the protrusion on the sealing body, the gasket is compressed when the terminal is installed, and the airtightness is improved. On the other hand, when the gasket is compressed by the protrusion, there is no escape place for the compressed meat, and a force is generated to push the penetrating portion of the sealing body open. Specifically, as shown in FIG. 6A, the gasket ₁ generates a force to expand the penetrating portion 5a of the sealing body 5 in the closed region S1. As a result, the sealing body may be deformed or in the state immediately before it. When the sealing body is deformed, the airtightness of the battery tends to decrease.

On the other hand, in the present disclosure, the volume of the sealing corresponding region (actual volume of the gasket) is designed so as to satisfy 0.53A ≤ V ₁ -V ₂ ≤ A. Therefore, as shown in FIG. 6B, in the closed region S1, the force for pushing the penetrating portion 5a of the sealing body 5 is less likely to be generated by the gasket ₁ , and the deformation of the sealing body 5 can be suppressed. _In FIG. 6B, the void G exists in the closed region S1, but the void G does not have to exist.

1. 1. Gasket The gasket in the present disclosure is a member arranged between the terminal and the sealing body. 5 (a) is a cross-sectional view taken along the line AA of FIG. 1 (a). As shown in FIG. 5A, the gasket 1 has at least a tubular portion 1a and a flange portion 1b arranged on one end surface of the tubular portion 1a. The flange portion is arranged between the external connection portion of the terminal and the main plane of the sealing body in the thickness direction, and insulates both. On the other hand, the tubular portion is arranged between the shaft portion of the terminal and the side surface of the penetrating portion of the sealing body in the direction orthogonal to the thickness direction, and insulates both of them. Further, the gasket is arranged in a compressed state between the terminal and the sealing body.

Further, in the present disclosure, when the volume of the sealed region is V ₁ , the volume of the sealed region is V ₂ , and the volume of the protrusion is A, 0.53 A ≤ V ₁ − V ₂ ≤ A is satisfied. .. This relationship will be described in detail with reference to FIGS. 4 and 5.

The sealed area is a reference area required for the gasket in order to exhibit hermeticity. The sealing area is (i) the side surface of the penetration part of the sealing body, (ii) the main plane on the outer surface side of the sealing body, (iii) the side surface of the terminal at the penetration part, and (iv) the top surface of the insulating member at the penetration part. Defined by. Specifically, as shown in FIG. ₄ , the line segment L1 is defined based on the side surface 51 of the penetrating portion 5a. Next, the line segment L2 is defined based on the main plane 52 on the outer surface side of the sealing body ₅ . The main plane is the plane having the largest area. Next, the line segment L3 is defined based _on the side surface 61 of the terminal (shaft portion) 6 in the penetrating portion 5a. Finally, the line segment L4 is defined based _on the top surface 71 of the insulating member 7 in the penetrating portion 5a. _A closed region _S1 is defined from the line segments L1 to _L4 , and its volume is _V1 . Further, let A be the volume of the protrusion 5b. If there are a plurality of protrusions, the total is taken as the volume A.

The hermetically sealed region is a region corresponding to the hermetically sealed region and is a region constituting a part of the gasket. Further, the hermetically sealed region is a region in the gasket in the uncompressed state (state before caulking). As shown in FIG. 5A, the gasket 1 has at least a tubular portion 1a and a flange portion 1b. The region X in the flange portion 1b is a portion compressed by the protrusion of the sealing body. As shown in FIG. 5B, the area of the gasket on the hollow portion _side of the tubular portion 1a is specified from the above _- mentioned line segment L1 and the area of the gasket is specified from the above _- mentioned line segment L2. The area of the gasket on one end side of the tubular portion 1a (the end face side opposite to the end face on which the flange portion 1b is arranged) is specified from L ₂ , and the sealing corresponding area S ₂ is defined from these specified areas. , The volume is V ₂ .

V ₁ , V ₂ and A are defined as described above and further satisfy 0.53 A ≤ V ₁ − V ₂ ≤ A. If V ₁ -V ₂ is smaller than 0.53 A, the deformation of the sealing body may not be sufficiently suppressed, and if V ₁ -V ₂ is larger than A, the airtightness may be deteriorated.

In addition, the area corresponding to the difference between the closed area and the closed area is defined as the wall thinning area. As shown in FIG. 7 (a), the wall thinning region 11 may be a region on the lower end side (insulating member side) of the closed region S1, and as shown in FIG. 7 (b), the wall thinning region 11 may be a region. , The area on the outer peripheral side (sealing body side) of the sealed area S1 may be used. Further, FIGS. 8 (a) and 8 (b) correspond to a plan view of the tubular portion 1a in FIG. 7 (b) observed from the lower side of the drawing. As shown in FIG. 8A, the thinning region 11 may be formed on the entire outer circumference of the tubular portion 1a, and as shown in FIG. 8B, the thinning region 11 is tubular. It may be formed on a part of the outer edge of the portion 1a. In particular, in FIG. 8B, the thinning region 11 is intermittently formed in the circumferential direction, so that the cross-sectional shape of the tubular portion 1a is a gear shape. Further, as shown in FIG. 7C, the wall thinning region 11 may be a region on the inner peripheral side (terminal side) of the closed region S1. Further, as shown in FIG. 7D, the wall thickness (distance in the left-right direction in the drawing) of the tubular portion 1a may be reduced toward the tip end (the side opposite to the flange portion 1b).

Further, the material of the gasket is preferably good in elasticity and insulating property, and examples thereof include an insulating resin such as a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA).

2. 2. Sealing body and exterior body The sealing body in the present disclosure is a member that seals the exterior body containing members such as power generation elements. As shown in FIG. 9, the sealing body 5 has a penetrating portion 5a for inserting a terminal (not shown). The plan view shape of the penetrating portion 5a is, for example, a circle. Further, the sealing body 5 has a protrusion 5b for enhancing the airtightness. In FIG. 9, the side surface 51 of the penetrating portion 5a and the side surface 53 of the protrusion 5b are flush with each other. The protrusion 5b in FIG. 9 is arranged along the side surface 51 of the penetration portion 5a, but the protrusion in the present disclosure can be arranged at an arbitrary position capable of enhancing the airtightness of the gasket. For example, the protrusion may be arranged at a position away from the side surface of the penetrating portion. It is preferable that the protrusion in the present disclosure is arranged at a position overlapping with the external connection portion of the terminal in a plan view. Further, the number of protrusions in the sealing body may be one or two or more. Further, the protrusion has, for example, an annular structure in a plan view. Further, examples of the cross-sectional view shape of the protrusion include a rectangle and a triangle.

The plan view shape of the sealing body is, for example, a rectangle. Further, the sealing body may have a gas discharge valve for releasing the internal pressure of the exterior body when the internal pressure of the exterior body rises. Further, the sealing body may have an injection port for injecting the electrolytic solution at the time of manufacturing the battery. The injection port is usually covered with a stopper, and the stopper is fixed by welding. As the material of the sealing body, the same material as the sealing body of the conventional battery can be used, but metal is preferable, and aluminum, stainless steel, and nickel-plated steel are particularly preferable.

On the other hand, the exterior body in the present disclosure has an internal space that can accommodate members such as power generation elements. Further, the exterior body has an opening at a position where the sealing body is arranged. As the material of the exterior body, the same material as the exterior body of the conventional battery can be used, but metal is preferable, and aluminum, stainless steel, and nickel-plated steel are particularly preferable.

3. 3. Terminal The terminal in the present disclosure is a member arranged in the penetrating portion of the sealing body, electrically connected to the current collecting member, and connected to the outside. As shown in FIG. 3, the terminal 6 preferably has an external connection portion 6a, a current collector connection portion 6b, and a shaft portion 6c. The external connection portion 6a is a portion for connecting to an external device. The plan view shape of the external connection portion 6a is, for example, a rectangle. The current collector connection portion 6b is a portion connected to the current collector member 3. The plan view shape of the current collector connection portion 6b is, for example, a circle. In particular, the current collector connection portion 6b is preferably a caulking portion formed by caulking. The shaft portion 6c is located between the external connection portion 6a and the current collector connection portion 6b, and is a portion arranged in the penetration portion 5a. The plan view shape of the shaft portion 6c is, for example, a circle. Further, the diameter of the shaft portion 6c is usually smaller than the diameter of the external connection portion 6a and the current collector connection portion 6b. Examples of the terminal material include metal.

Further, in the present disclosure, the terminal may have a protrusion for enhancing the airtightness. For example, the terminal 6 shown in FIG. 10 has a protrusion 6d that protrudes outward from the shaft portion 6c and is arranged so as to come into contact with the external connection portion 6a. It is preferable that the protrusion 6d is arranged so as to overlap with at least a part of the tubular portion 1a of the gasket 1 in a plan view. Further, although not particularly shown, both the sealing body and the terminal may each have a protrusion.

4. Current collector member The current collector member in the present disclosure is a member housed in an exterior body, collects current from a power generation element, and is responsible for electron conduction between the power generation element and terminals. The shape of the current collector member is not particularly limited, but includes, for example, a plate-shaped portion for connecting to a terminal and a current collector for connecting to a power generation element. The plate-shaped portion and the current collecting portion may be continuously formed, or an intermediate portion may be arranged between them. Further, as shown in FIG. 3, the current collecting member 3 (plate-shaped portion) preferably has a penetrating portion 3a into which the shaft portion 6c of the terminal 6 is inserted. Examples of the material of the positive electrode current collector member include Al and Al alloys, and examples of the material of the negative electrode current collector member include Cu and Cu alloys.

5. Insulating member The insulating member in the present disclosure is a member that is arranged between a sealing body and a current collecting member and electrically insulates both. The shape of the insulating member is not particularly limited, and examples thereof include a plate shape. Further, as shown in FIG. 3, the insulating member 7 preferably has a penetrating portion 7a into which the shaft portion 6c of the terminal 6 is inserted. Further, as shown in FIG. 9, the insulating member 7 may have a thin-walled portion 7b at a position overlapping the penetrating portion 5a in a plan view. By providing the thin portion 7b, the airtightness and the insulating property are improved. The thin portion 7b is a portion having a thickness smaller than the thickness (reference thickness) of the insulating member overlapping with the protrusion 5b in a plan view. Examples of the material of the insulating member include insulating resins such as polyphenylene sulfide resin (PPS), polypropylene (PP), and polyethylene (PE). Insulating members are usually stiffer than the gaskets described above.

6. Power generation element The power generation element in the present disclosure is not particularly limited as long as it can generate power. The power generation element is, for example, a positive electrode layer, a negative electrode layer, an electrolyte layer formed between the positive electrode layer and the negative electrode layer, a positive electrode current collector that collects electricity from the positive electrode layer, and a collection of the negative electrode layers. It has a negative electrode current collector that conducts electricity.

The positive electrode layer has, for example, a positive electrode active material, an electrolyte, a conductive material and a binder. Examples of the positive electrode active material include lithium cobalt oxide. The electrolyte may be a liquid electrolyte (electrolyte solution) or a solid electrolyte. The electrolytic solution contains, for example, a supporting salt such as LiPF ₆ and a solvent such as a carbonate solvent. Examples of the solid electrolyte include organic solid electrolytes such as gels; inorganic solid electrolytes such as oxide solid electrolytes and sulfide solid electrolytes. Examples of the conductive material include a carbon material. Examples of the binder include a fluorine-based binder such as PVDF.

The negative electrode layer has, for example, a negative electrode active material, an electrolyte, a conductive material and a binder. Examples of the negative electrode active material include graphite and Li. The electrolyte, conductive material and binder used for the negative electrode layer are the same as those used for the positive electrode layer described above. Further, the electrolyte layer contains at least an electrolyte. The electrolyte may be a liquid electrolyte (electrolyte solution) or a solid electrolyte in the same manner as described above. The electrolytic solution may be impregnated in a separator arranged between the positive electrode layer and the negative electrode layer. Further, examples of the positive electrode current collector include Al foil and Al alloy foil. Examples of the negative electrode current collector include Cu foil and Cu alloy foil.

The power generation element may be a wound body obtained by winding a sheet having a positive electrode layer, an electrolyte layer (separate layer) and a negative electrode layer, and the thickness of the sheet having the positive electrode layer, the electrolyte layer (separate layer) and the negative electrode layer may be used. It may be a laminated body in which a plurality of layers are laminated in the direction. The plurality of laminated sheets may be connected in series with each other or may be connected in parallel. Further, the power generation element may be covered with an insulating protective film.

7. Battery The type of battery in the present disclosure is not particularly limited, but is typically a lithium ion secondary battery. The use of the battery is not particularly limited, and examples thereof include a power source for a vehicle such as a hybrid vehicle, an electric vehicle, a gasoline vehicle, and a diesel vehicle. In particular, it is preferably used as a power source for driving a hybrid electric vehicle or an electric vehicle. Further, the battery in the present disclosure may be used as a power source for a moving body other than a vehicle (for example, a railway, a ship, an aircraft), or may be used as a power source for an electric product such as an information processing device.

The present disclosure is not limited to the above embodiment. The above embodiment is an example, and any object having substantially the same structure as the technical idea described in the claims of the present disclosure and having the same effect and effect is the present invention. Included in the technical scope of the disclosure.

1 ... Gasket 2 ... Power generation element 3 ... Current collector 4 ... Exterior 5 ... Sealing body 6 ... Terminal 7 ... Insulation member 10 ... Battery

Claims (2)

A gasket placed between the terminal and the sealing body in the battery.
It has a tubular portion and a flange portion arranged on one end surface of the tubular portion.
The volume of the sealed region defined by the side surface of the penetrating portion of the sealing body, the main plane on the outer surface side of the sealing body, the side surface of the terminal in the penetrating portion, and the top surface of the insulating member in the penetrating portion is V ₁ . year,
The _volume of the sealing area of the gasket corresponding to the sealing area is V2.
When the volume of the protrusions arranged to enhance the airtightness on at least one of the sealing body and the terminal is A.
A gasket that satisfies 0.53A ≤ V ₁ -V ₂ ≤ A. Power generation elements and
A current collector member that collects power from the power generation element and
An exterior body that houses the power generation element and the current collector member,
A sealing body that seals the exterior body and has a penetrating portion,
A terminal arranged in the penetration portion and electrically connected to the current collector member,
A gasket placed between the terminal and the sealing body,
An insulating member arranged between the sealing body and the current collecting member, and
It is a battery with
At least one of the sealing body and the terminal has a protrusion for enhancing the airtightness, and has a protrusion.
The gasket has a tubular portion and a flange portion arranged on one end surface of the tubular portion.
The volume of the sealed region defined by the side surface of the penetration portion, the main plane on the outer surface side of the sealing body, the side surface of the terminal in the penetration portion, and the _top surface of the insulating member in the penetration portion is defined as V1.
The _volume of the sealing area of the gasket corresponding to the sealing area is V2.
When the volume of the protrusion is A,
A battery satisfying 0.53A ≤ V ₁ -V ₂ ≤ A.

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