JPH07142040A - Battery - Google Patents

Abstract

PURPOSE:To discharge effectively gas generated the inside of the casing of a battery. CONSTITUTION:A battery B housing a large number of battery cells inside has an almost cubic-shaped casing 1, and gas holes 18 to discharge gas generated inside of the casing 1 are arranged in the centers of the four side walls. Gas passages 17 are formed in a cross shape on the respective side walls, and the gas holes 18 are opened at intersections between these gas passages 17. When plural batteries B are used by joining them together, the gas passages 17 on the mutually close contact two side walls cooperate with each other, and constitute a cylindrical gas passage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery capable of effectively discharging gas discharged from the inside of a casing.

[0002]

2. Description of the Related Art For example, as a traveling battery mounted on an electric vehicle, a sealed type battery in which a large number of battery cells are stacked in a casing is used. Such a battery has a gas hole that communicates the inside and outside of the casing, and the gas generated inside the battery is discharged to the outside through the gas hole.

[0003]

By the way, when such a sealed battery is mounted on a vehicle body, if the surface of the casing is brought into close contact with the battery supporting portion of the vehicle body, the gas holes are closed and it becomes difficult to discharge the gas. There's a problem. When using multiple batteries connected in series or in parallel,
Even if it is considered that the gas hole is not blocked when the battery is mounted on the vehicle body, there is a problem that the gas passage communicating with the gas hole is blocked and it becomes difficult to discharge the gas. Further, if a separate pipe is connected to discharge the gas, the connection may be troublesome, and the gas may leak due to the pipe coming off or a hole being formed for some reason.

The present invention has been made in view of the above circumstances, and an object thereof is to effectively discharge gas discharged from the inside of a casing of a battery.

[0005]

In order to achieve the above object, the invention described in claim 1 is characterized in that a gas passage is formed on the outer wall surface of the casing.

[0006] According to a second aspect of the present invention, a gas passage is formed on the outer wall surface of the casing, the gas passage forming a gas passage in cooperation with a gas passage formed on the outer wall surface of another casing connected to this casing. It is characterized by being formed.

The invention described in claim 3 is characterized in that, in addition to the structure of claim 1 or 2, the casing has a substantially rectangular parallelepiped shape, and the end of the gas passage is opened at the center of its side. And

According to a fourth aspect of the invention, in addition to the configuration of the second aspect, the casing has a substantially rectangular parallelepiped shape,
The gas passage is formed on the center line of the outer wall surface.

The invention described in claim 5 is characterized in that, in addition to the structure of claim 4, the gas passages are formed in a cross shape orthogonal to each other.

The invention described in claim 6 is characterized in that, in addition to the structure according to any one of claims 1 to 5, a gas hole for discharging gas from the inside of the casing is opened inside the gas passage. And

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 show a first embodiment of the present invention. FIG. 1 is an overall perspective view of a battery, and FIG.
2 is a sectional view taken along line 2, FIG. 3 is an enlarged view of part 3 in FIG. 2, FIG. 4 is a view showing a state in which batteries are connected in series, and FIG.

As shown in FIGS. 1 and 2, the battery B includes a casing 1 having a substantially cubic shape. Casing 1
Is a first casing 2 and a second casing made of a conductive elastic body.
It comprises a casing 3 and a third casing 4 made of non-conductive synthetic resin. The rigidity of the casing 1 can be increased by laminating the conductive carbon fibers on the elastic body forming the first casing 2 and the second casing 3. The first casing 2 is bonded to the upper end of the third casing 4 with an ABS resin adhesive or an epoxy resin adhesive via the spigot portion 5, and the second casing 3
Is attached to the lower end of the third casing 4 through the spigot portion 6 and
The first and second casings 2 and 3 are electrically insulated from each other by the S resin adhesive or the epoxy resin adhesive.

As can be seen by referring also to FIG.
Inside the casing 1, a plurality of bipolar type current collector plates 7 ... And a plurality of separators 8 ... Are alternately stacked and housed. Each current collector plate 7 is formed by applying a positive electrode active material 10 and a negative electrode active material 11 to the front and back surfaces of a substrate 9 formed of lead or conductive synthetic resin, and a frame-shaped insulating material 12 on the outer periphery thereof. Is installed. A battery cell 13 is composed of the separator 8 and the positive electrode active material 10 and the negative electrode active material 11 provided on the lower surface and the upper surface thereof. The battery cells 13 are connected in series by alternately stacking the collector plates 7 and the separators 8, and the positive electrode active material 10 of the uppermost collector plate 7 contacts the inner surface of the first casing 2. At the same time, the negative electrode active material 11 of the lowermost collector plate 7 contacts the inner surface of the second casing 3.
In this embodiment, all the current collector plates 7 have the same structure, but the positive electrode active material 10 of the uppermost current collector plate 7 and the negative electrode active material 11 of the lowermost current collector plate 7 may be omitted. it can. When the first and second casings 2 and 3 are bonded to the third casing 4, a predetermined pressure is applied to each current collector plate 7 in the stacking direction, whereby the positive electrode active material 10 and the negative electrode active material. The life of the battery B can be extended by preventing the deterioration of the battery 11 due to the dropping or the like.

On the upper surface of the first casing 2 are provided positive electrode terminals 14 _1, ...
Positive electrode terminals 14 ₂ and 14 ₂ formed by two parallel protrusions and positive electrode terminals 15 ₃ and 15 ₃ formed by two parallel concave grooves are formed on two side surfaces of the first casing 2 which face each other. To be done. On the other hand, the the lower surface of the second casing 3 is the negative terminal 15 ₁ ... made of four parallel grooves of the recessed, the two side surfaces facing each other of the second casing 3 two parallel projections Negative electrode terminals 14 ₃ and 14
Negative electrode terminal 15 ₂ , 15 consisting of ₃ and two parallel grooves
₂ and are formed respectively. In addition, the positive electrode terminals 14 ₂ and 14 ₂ of the first casing ₂ and the negative electrode terminal 1 of the second casing 3 are provided on two opposite side surfaces of the third casing 4.
Two protrusions 16 ₁ , 1 to connect with 4 ₃ , 14 _3.
6 ₁ is formed, and the positive electrode terminals 15 ₃ and 15 ₃ of the first casing 2 and the negative electrode terminal 1 of the second casing 3 are formed.
_Two concave grooves 16 ₂ , 1 so as to connect with 5 ₂ , 15 _2.
6 ₂ is formed.

The positive terminal 14 ₁ of the first casing 2 can be fitted to the negative terminal 15 ₁ of the second casing 3,
In addition, the positive electrode terminals 14 ₂ and 14 _{2 of} the first casing ₂ and the second
The negative electrode terminals 14 ₃ and 14 ₃ of the casing ₃ and the protrusions 16 ₁ and 16 ₁ of the third casing 4 are the positive electrode terminals 15 ₃ and 15 ₃ of the first casing 2 and the negative electrode terminals 15 ₂ and 15 _{2 of} the second casing 3, respectively. And the concave groove 16 of the third casing 4
₂ , 16 ₂ can be fitted.

The positive electrode terminal 14₁… ； 14₂, 14₂Over
And negative terminal 14₃, 14₃Constitutes the convex terminal of the present invention
The negative electrode terminal 15₁…; 15₂, 15₂And positive end
Child 15 ₃, 15₃Constitutes the concave terminal of the present invention.

Gas passages 17, 17 are engraved in a cross shape on the center line on the four side surfaces of the casing 1, and gas holes 18 for communicating the inside and outside of the third casing 4 are formed at their intersections. It is formed. When a plurality of batteries B are connected in parallel, a gas passage 19 (see FIG. 5) is formed by the gas passages 17, 17 on the coupling surface of the pair of casings 1. Thus, by configuring the gas passage 19 by the pair of gas passages 17, 17 facing each other, it is possible to secure the cross-sectional area of the gas passage 19 while reducing the thickness of the casing 1 and reducing the weight. it can. Even when the casing 1 of the battery B is mounted so as to be in close contact with the wall surface of the vehicle body, the gas passages 17, 17
The gas can be effectively discharged via the.

Further, since the gas passages 17, 17 are constructed without using separate pipes, there is no fear of pipe disconnection or gas leakage. Furthermore, when an appropriate pressure is applied to electrically or structurally connect the battery B or to apply a tight pressure to the current collector plates 7, ..., The gas passages 17 are connected at an appropriate pressure. As a result, the gas passage 19 is formed. Although not shown, the gas passages 17, 17 are covered with an insulating layer.

Two batteries B, B having the above-mentioned structure
In order to obtain a large voltage by connecting the two in series, the upper surface of the first casing 2 located at the upper end of the lower battery B and the second casing located at the lower end of the upper battery B are connected as shown in FIG. 3 should be piled up. As a result, the four positive electrode terminals 14 ₁ ...
And the negative terminal 15 _first fitting ... the four that are recessed in the casing 3, two batteries B, B are connected in series.

Further, in order to obtain a large current by connecting two batteries B, B in parallel, as shown in FIG. 5, the right wall surface of the left battery B may be connected to the left wall surface of the right battery B. Good. Thereby, the positive electrode terminal 15 of the battery B on the left side
₃ and 15 ₃ are positive terminals 14 ₂ and 14 ₂ of the battery on the right side
And the negative electrode terminals 15 ₂ and 1 of the battery B on the left side
5 ₂ is fitted to the negative terminals 14 ₃ and 14 ₃ of the right battery, and the two batteries B and B are connected in parallel.

When the two batteries B, B are connected in parallel as shown in FIG. 5, the gas passages 19 are formed by the gas passages 17, 17 which are recessed so as to face each other on the coupling wall surfaces of the batteries B, B. Therefore, the gas discharged from the gas holes 18, 18 opening in the gas passages 17, 17 is discharged to the outside through the gas passage 19.

In the same manner as described above, three or more batteries B ...
Can be connected in series or in parallel, and a large voltage and large current can be obtained by connecting a plurality of groups of batteries B ... Connected in series in parallel.

Thus, the positive electrode terminal projecting from the casing 1
14₁… ； 14₂, 14₂And the negative electrode terminal 14₃, 14₃
Negative electrode terminal 15 in which the casing 1 is recessed₁…; 15₂，
15 ₂And the positive electrode terminal 15₃, 15₃To fit in
Since more than one battery B is electrically connected,
Battery B ... Prevents contact failure due to mutual displacement
In addition to being stopped, the cords and metal
The rate becomes unnecessary and the weight of the cord and the metal plate
Space can be reduced and connection work is required
This can greatly reduce the labor required In addition,
Short circuit or misdelivery that tends to occur when using a metal plate or metal plate
It is possible to avoid troubles such as lines. Well
In addition, since the electrodes are made of a conductive elastic material,
Keep the surface pressure of the part even and prevent contact failure
And the whole or most of the surface of the casing 1
Since it is an electrode, increase the contact area between the electrodes
It is possible to reduce electric resistance and prevent contact failure.

Further, since the electrodes are thin, the electric passage length of the electrodes can be greatly shortened, and therefore the electric resistance can be reduced. Furthermore, it is not necessary that all of the electrodes are conductive elastic bodies, and the contactability is improved even if the head is made of metal, for example. Furthermore, if at least one of the fitted terminals absorbs vibration, the contactability is improved.

6 to 10 show a second embodiment of the present invention. FIG. 6 is an overall perspective view of the battery, and FIG. 7 is 7 of FIG.
FIG. 8 is a sectional view taken along line 8-8 of FIG. 6, FIG. 9 is a diagram showing a state where batteries are connected in series, and FIG. 10 is a diagram showing a state where batteries are connected in parallel.

As shown in FIGS. 6 to 8, the battery B of the second embodiment is provided with a first casing 2, a second casing 3 and a third casing 4 which are all made of non-conductive synthetic resin. , The first and second ends on the upper and lower ends of the third casing 4, respectively.
The casings 2 and 3 are spigot-fitted and adhered to each other, and the same collector plate 7 ... And separator 8 ...
Are stored in a stacked state. Cross-shaped gas passages 17, 17 are engraved on the two side surfaces of the casing 1, and
One gas passage 17 is engraved on the other two side surfaces, and a gas hole 18 is opened at the center of these gas passages 17, 17.

A positive electrode member 20 formed of a conductive elastic material or a copper plate is fitted and held on the inner surface of the upper wall of the first casing 2, and the three positive electrodes integrally projecting from the positive electrode member 20. The terminals 14 ₁ penetrate the upper surface of the first casing 2 and project upward. Three positive electrode terminals 14 _2, ..., 15 ₃ are formed at both ends of the three positive electrode terminals 14 ₁ ,. The positive electrode terminal 14 ₂ ... projects outward from one side wall of the first casing 2, and the positive electrode terminal 15 ₃ ...
It is retracted inward from the other side wall of the casing 2.

Further, a negative electrode member 21 formed of a conductive elastic body or a copper plate is fitted and held on the inner surface of the lower wall of the second casing 3, and the three negative electrodes 21 are integrally recessed. Negative electrode terminals 15 ₁ ... Are exposed on the lower surface of the second casing 3. Each of the three negative electrode terminals 15 _1, ...
The negative electrode terminals 14 ₃ ..., 15 ₂ ... Are formed. The negative electrode terminals 14 ₃ ... project outward from one side wall of the second casing 3, and the negative electrode terminals 15 ₂ ... reced inward from the other side wall of the second casing 3.

One side wall of the first and second casings 2 and 3
Positive electrode terminal 14 protruding to₂... and the negative electrode terminal 14₃Touch ...
So as to continue, the first to third casings 2, 3, 4 are projected
16 ₁Are formed, and the first and second casings are formed.
Positive electrode terminal 15 recessed on the other side wall of 2, 3₃…as well as
Negative electrode terminal 15₂1st to 3rd case to connect ...
Grooves 2, 3 and 4 with groove 16₁... is formed.

In order to connect the two batteries B, B in series, as shown in FIG. 9, on the upper surface of the first casing 2 located on the upper end of the lower battery B, and on the lower end of the upper battery B, The second casing 3 located is superposed, and the three positive electrode terminals 14 ₁ ... protruding from the first casing 2 are fitted to the three negative electrode terminals 15 ₁ ... recessed in the second casing 3. Good. To connect the two batteries B in parallel, as shown in FIG. 10, the right wall surface of the left battery B is joined to the left wall surface of the right battery B, and the positive terminal of the left battery B is connected. 15 ₃ ... May be fitted to the positive electrode terminal 14 ₂ of the right battery, and the negative electrode terminal 15 ₂ of the left battery B may be fitted to the negative electrode terminal 14 ₃ of the right battery.

Thus, according to the second embodiment, in addition to the effect of the first embodiment described above, the negative electrode terminals 15 ₁ ... Are more than the bottom surface of the second casing 3 formed of the non-conductive synthetic resin. because it is located inside, or on the floor surface of the battery B in a posture of Fig. 8, Ya negative terminal 15 ₁ ... floor surface when carrying the metal plate on the upper surface in the upside down orientation as FIG. 8 It is possible to prevent the occurrence of electric leakage without coming into contact with the metal plate.

11 to 15 show a third embodiment of the present invention. FIG. 11 is an overall perspective view of the battery, FIG. 12 is a view taken in the direction of arrow 12 in FIG. 11, and FIG. 13 is a cross-sectional view taken along line 13, FIG. 14 is a diagram showing a state where batteries are connected in series, and FIG. 15 is a diagram showing a state where batteries are connected in parallel.

The battery of the third embodiment has a positive electrode member 2
0 and the negative electrode member 21 are formed of a conductive elastic body. Then, the positive electrode terminals 14 ₁ ... 14 ₂ ... And the negative electrode terminal 14 ₃
, And the cross-sectional shapes of the negative electrode terminals 15 _1, ..., 15 ₂ and the positive electrode terminal 15 ₃ ... Are formed in trapezoid shapes that can be fitted to each other and are so-called dovetail-groove-connected. is doing. The other structure is the same as that of the second embodiment described above.

Thus, according to this third embodiment,
Terminal 14₁…, 14₂…, 14₃… And concave terminal 15₁
…, 15₂…, 15₃… And pressed against each other to elastically deform
14 and 15 by fitting while
Connect multiple batteries B ... in series or in parallel as shown.
You can At this time, the terminal 14₁…, 14 ₂
…, 14₃…; 15₁…, 15₂…, 15₃Contact surface
Since the surface pressure due to the elasticity of the conductive elastic body acts on,
There is no risk of contact failure even if vibration is applied from the outside.
Yes. In addition, at least one of the mating electrodes has a conductive
If it is a body, the contact property is improved.

16 and 17 show a fourth embodiment of the present invention. FIG. 16 is a longitudinal sectional view of a battery, and FIG. 17 is a view showing a state where the batteries are connected in an L shape.

The cubic casing 1 of the battery B according to the fourth embodiment is formed of a conductive elastic body and has a container-shaped second casing 3 having an open upper surface, and a conductive elastic body. A flat plate-shaped first casing 2 that covers the upper surface opening of the second casing, and a frame-shaped third casing 4 formed of a non-conductive synthetic resin in order to insulate between the second casing 3 and the first casing 2 are provided. Prepare The first casing 2 constitutes a positive electrode as a whole, and a positive electrode terminal 14 ₁ is formed of four protrusions on its upper surface. The second casing 3 constitutes the anode as a whole, together with the negative electrode terminal 15 made of four grooves ₁ ... is formed on the bottom surface thereof, than the four grooves so as to surround the four sides the negative terminal 15 ₂ ... are formed comprising.

Thus, as is apparent from FIG. 17, the first
Positive electrode terminal 14 ₁ provided on the upper surface of the battery B (B1) of
Negative electrode terminal 1 provided on the lower surface of the second battery B (B2)
The third battery B connected to 4 ₁ ... and further laid down sideways
(B3) positive electrode terminal 14 ₁ ... Is connected to the first battery B
The three batteries B can be electrically connected in series and in an L-shape by being coupled to the negative electrode terminal 15 ₂ provided on any side surface of (B1). In this way, by connecting a plurality of batteries B in any direction,
A large number of batteries B can be effectively laid out in a narrow space.

Further, cross-shaped gas passages 17, 17 each having a gas hole 18 at the center are formed on the five outer wall surfaces of the second casing 3 constituting the negative electrode. Reference numeral 17 forms a tubular gas passage 19 in cooperation with the outer wall surface of the first casing 2.

FIG. 18 shows a fifth embodiment of the present invention. In this embodiment, two types of batteries B having different structures are used.
(B1, B2) is used. That is, both batteries B (B
1, B2) both have a cubic shape without a protrusion and a groove for coupling, and the first battery B (B1) has a positive electrode and a negative electrode on two surfaces facing each other, and a second battery (B2). Has a positive electrode and a negative electrode on two adjacent surfaces.

Then, the negative electrode of the first battery B (B1) is connected to the positive electrode of the second battery B (B2) with the plate-shaped conductive elastic body 22 interposed therebetween, and By connecting the positive electrode of the first battery B (B1) to the side of the negative electrode of the second battery B (B2) with the elastic body 22 interposed therebetween, the three batteries B are electrically connected in series and L-shaped. Can be connected in a shape. Also according to the fifth embodiment, it is possible to connect a plurality of batteries B in arbitrary directions to effectively utilize the space. A frame-shaped non-conductive member 23 is integrally provided on the periphery of the elastic body 22 to prevent a short circuit.

Gas passages 17, 17 each having a gas hole 18 at the center are formed on the six outer walls of the battery B (B1, B2).
Are formed in a cross shape, and the battery B (B1, B
The central portion of each side of the non-conductive member 23 is bent inward so as not to block the gas passages 17, 17 when the second connection is made. In this embodiment, two adjacent surfaces have different polarities, but they may have the same polarities.

FIG. 19 shows a sixth embodiment of the present invention.
The battery B is substantially the same as the battery B of the first embodiment.
It has the same structure but its positive electrode terminal 14₁…, 14
₂…, 15 ₃... and the negative electrode terminal 15₁…, 15₂…, 14
₃Is composed of an inelastic body. And, for example, two
When connecting the batteries B in series, the positive electrode terminal 14₁…
And the negative electrode terminal 15₁… Matches the shape of the protrusion and groove between
Sandwich the corrugated conductive elastic body 22
By inserting it, the surface pressure of the contact part is made uniform and the electric resistance
Reduction and contact failure can be prevented.

Like the elastic body 22 of the fifth embodiment, the elastic body 22 of the sixth embodiment is integrally provided with a frame-shaped non-conductive member 23 for preventing a short circuit.

In each embodiment, after connecting the battery B while pressing it, the unused gas hole 18, gas passage 17,
17 and the ends of the gas passage 19 are closed and also the exposed electrodes are insulated.

Although the embodiments of the present invention have been described above in detail, the present invention is not limited to the above embodiments, and various design changes can be made.

For example, the battery of the embodiment has a plurality of battery cells inside the casing, but the present invention can also be applied to a battery having a single battery cell inside the casing. The battery mentioned here is not limited to the secondary battery.

[0048]

As described above, according to the invention described in claim 1, the gas passage is formed on the outer wall surface of the casing, so that the casing of the battery is brought into close contact with the other article or the casing of the other battery. Even in such a case, the gas discharged from the battery can be effectively discharged through the gas passage. Moreover, since a separate pipe is not used, it is possible not only to save the labor of connection and the like, but also to prevent gas leakage due to disconnection and perforation of the pipe.

According to the invention described in claim 2,
When connecting a plurality of casings, the gas passages of both casings cooperate to form a gas passage, so that the gas can be effectively discharged through the gas passage having a sufficient cross-sectional area. Moreover, if an appropriate pressure is applied to electrically or structurally connect the batteries or to apply a tight pressure,
The gas passage can be reliably formed by the appropriate pressure.

According to the invention described in claim 3,
By opening the end of the gas passage in the center of the side of the casing having a substantially rectangular parallelepiped shape, it is possible to connect the gas passages of the casings in series and discharge the gas when a plurality of casings are combined.

According to the invention described in claim 4,
By forming the gas passage on the center line of the outer wall surface of the substantially rectangular parallelepiped-shaped casing, it is possible to configure the gas passage so that the gas passages of both casings face each other without displacement when connecting a plurality of casings. .

According to the invention described in claim 5,
By forming the gas passages in a cross shape orthogonal to each other, it is possible to reliably discharge the gas by the gas passages extending in two directions.

According to the invention described in claim 6,
By opening the gas hole for discharging the gas from the inside of the casing to the inside of the gas passage, the gas discharged from the gas hole can be directly guided to the gas passage and quickly discharged.

[Brief description of drawings]

FIG. 1 is an overall perspective view of a battery according to a first embodiment.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is an enlarged view of part 3 in FIG.

FIG. 4 is a diagram showing a state where batteries are connected in series.

FIG. 5 is a diagram showing a state in which batteries are connected in parallel.

FIG. 6 is an overall perspective view of a battery according to a second embodiment.

7 is a view in the direction of arrow 7 in FIG. 6;

8 is a sectional view taken along line 8-8 of FIG.

FIG. 9 is a diagram showing a state where batteries are connected in series.

FIG. 10 is a diagram showing a state in which batteries are connected in parallel.

FIG. 11 is an overall perspective view of a battery according to a third embodiment.

FIG. 12 is a view from the direction of arrow 12 in FIG.

13 is a sectional view taken along line 13-13 of FIG.

FIG. 14 is a diagram showing a state where batteries are connected in series.

FIG. 15 is a diagram showing a state where batteries are connected in parallel.

FIG. 16 is a vertical sectional view of a battery according to a fourth embodiment.

FIG. 17 is a diagram showing a state in which batteries are connected in an L shape.

FIG. 18 is a diagram showing a state in which batteries according to the fifth embodiment are connected in an L shape.

FIG. 19 is a diagram showing a state in which batteries according to the sixth embodiment are connected in series.

[Explanation of symbols]

 1 Casing 17 Gas passage 18 Gas hole 19 Gas passage

Claims (6)

[Claims] 1. A battery, characterized in that a gas passage (17) is formed on the outer wall surface of the casing (1). 2. A gas passage (19) on the outer wall surface of a casing (1) in cooperation with a gas passage (17) formed on the outer wall surface of another casing (1) connected to this casing (1). A battery having a gas passage (17) constituting the battery. 3. The battery according to claim 1, wherein the casing (1) has a substantially rectangular parallelepiped shape, and an end of the gas passage (17) is opened at the center of the side thereof. 4. The battery according to claim 2, wherein the casing (1) has a substantially rectangular parallelepiped shape, and the gas passage (17) is formed on the center line of the outer wall surface thereof. 5. The battery according to claim 4, wherein the gas passages (17) are formed in a cross shape orthogonal to each other. 6. The gas hole (18) for discharging gas from the inside of the casing (1) is opened in the inside of the gas passage (17), according to any one of claims 1 to 5. Battery.