JP3204126B2 - Battery pressure valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure valve for a battery. More particularly, the present invention relates to a pressure valve that is housed in a battery, opens when the pressure in the battery increases, and releases internal pressure.

[0002]

2. Description of the Related Art A battery has an overcurrent, heat generated due to an abnormal reaction,
A pressure valve is provided to prevent rupture due to an increase in internal pressure or the like. The pressure valve is housed in the battery, and is configured to open as the pressure in the battery increases and release the internal pressure.

FIG. 3 is a plan view showing a conventional battery pressure valve. In the figure, reference numeral 1 denotes a pressure valve, and a groove-shaped recess 4 having a substantially cross shape is formed in the center of a disk-shaped metal plate 3 having a flange 2. The disc 3 has a substantially uniform thickness as a whole, and the recess 4 is configured to have a uniform thickness smaller than the thickness.

The above-described pressure valve 1 is manufactured by forming a groove-shaped concave portion 4 by press molding at the same time as forming a flange 2 by punching a metal plate 3 in a circular shape. Such a pressure valve is integrated with a PTC element, a positive electrode terminal and the like and is housed in a battery for use.

[0005] When the internal pressure of the battery rises due to the occurrence of an abnormal state such as an overcurrent or an abnormal reaction in a use state, cracks enter the thin and low-strength concave portion 4 to release gas and release the internal pressure. This prevents accidents due to battery rupture.

[0006]

However, in the conventional battery pressure valve as described above, it is easy to form the metal plate 3 itself to have a constant thickness with a uniform material so that the strength is constant. Since the groove-shaped concave portion 4 is formed by press working, a constant thickness (depth of the groove) due to variations in processing conditions.
It is difficult to do. For this reason, the operating pressure of the pressure valve 1 is greatly different due to the variation of the thickness of the recess 4 formed, and there is a problem that safety and reliability cannot be maintained.

An object of the present invention is to provide a simple structure and a constant operating pressure, thereby improving safety and reliability and integrally forming with other elements.
Possible, it is that the housing into the cell to provide a pressure valve for easy battery.

[0008]

The present invention relates to the following battery pressure valve. (1) a conductor layer provided for another element in the battery and connected to the positive electrode or the negative electrode on both sides of the insulating substrate ; and
A laminated substrate in which conductor layers connected to terminals were laminated, and provided on the substrate as through holes for conducting the conductor layers on both sides through a conductive layer in the periphery , and provided to detect the pressure inside the battery. A battery pressure valve having a through-hole and a sheet-like closing member provided to cover the through-hole and fixed to a substrate around the through-hole. (2) The battery pressure valve according to the above (1), wherein the closing member is made of a metal foil, and is fixed to the base material by the fixing member.

The substrate constituting the battery pressure valve of the present invention comprises:
This is a laminated substrate that is also used for other devices. Although the material of the substrate is not particularly limited, copper, aluminum or the like is provided on both sides of the edge substrate so that the positive or negative electrode can be connected to the terminal.
Conductor layer connected to positive or negative electrode, and terminal
You form that conductor layer. The substrate can have any shape such as a circle or a quadrilateral according to the shape of the battery.

The through-hole formed in the substrate is provided as a through-hole for conducting the conductive layers on both sides of the substrate with a conductive layer in the peripheral portion, and detects the pressure inside the battery,
The shape of the pressure valve is not limited as long as it can release gas and release the internal pressure after the operation of the pressure valve. However, it is preferable that the pressure valve be circular so that the pressure is uniformly applied to the closing member. The size of the through hole varies depending on the material, thickness, set pressure, and the like of the closing member. For example, in the case of a circular shape, the diameter is about 0.5 to 10 mm, and preferably about 1 to 4 mm. The through hole also serves as the through hole of the pressure valve and the through hole of the substrate.

[0011] The closing member is a sheet-like member that can be formed into a uniform thickness, and includes those called plates, foils, films, sheets and the like. The material is not limited as long as it can provide a uniform breaking strength, but a metal material having a small change in strength over time is preferable. Specifically, a copper plate that can be easily soldered is preferable. The thickness of the closing member varies depending on the material, dimensions, set pressure, and the like.
μm, preferably 10 to 50 μm, and 5 to 200 μm when using an aluminum plate, preferably 15 to 80 μm.
Use about

Although the shape of the closing member is arbitrary, it is preferable that the closing member be circular in accordance with the through hole. The closing member has an outer shape larger than the through hole, and is fixed to the substrate around the through hole. As a fixing material, soldering, adhesive, welding, etc.
Although it can be arbitrarily selected, when metal is used for the substrate and the closing member, soldering is preferable. The fixing is performed such that the periphery of the through hole is completely closed and the passage of the gas liquid is blocked, so that the fixing strength is higher than the breaking strength of the closing member. The fixing is performed so that the portion surrounded by the fixing portion is preferably circular and has a fixed area.

The above-mentioned pressure valve is integrated with the PTC element and other elements and the positive electrode terminal and housed in a battery to form a battery. In use, when the internal pressure of the battery rises due to the occurrence of an overcurrent or abnormal condition, the closing member is broken at the time when the pressure reaches a certain pressure, whereby the internal gas leaks and the internal pressure is released, and the battery is ruptured. Accidents are prevented.

Since the closing member is formed in a sheet shape, unlike the concave portion formed by the conventional press working, it is easy to make the thickness of the closing member constant, and therefore, it is necessary to control the breaking strength to be constant. Can be. Therefore, by keeping the size of the through hole constant and the area receiving the internal pressure of the closing member constant, the operating pressure of the valve can be controlled to a constant value, thereby increasing safety and reliability. The operating pressure can be set arbitrarily by changing the thickness of the closing member or the size of the through hole.

[0015] The above pressure valve, the from structure of the pressure valve itself can be easily miniaturized, addition can be easily accommodated in the battery, a through hole of a substrate for other elements
Since it is used as it is, by combining it with another element, the effect of further miniaturization and multifunctionalization can be obtained. sand
KazuSatoshi case of using a multi-layer board for other elements may constitute the pressure valve by utilizing the substrate. In this case it forms a through hole in the substrate for the other elements,
By using the through-hole as a through-hole, a pressure valve can be easily formed, the entire device can be reduced in size, and a small battery can be accommodated.

The pressure valve of the present invention can be used for all batteries, regardless of whether it is a primary battery or a secondary battery. The shape of the battery can also be used for batteries having an arbitrary shape such as a cylindrical shape, a square shape, and a button shape. As the primary battery, a non-aqueous battery and an aqueous battery can be used. Examples of the non-aqueous battery include a lithium graphite fluoride battery, a lithium thionyl chloride battery, a lithium silver chromate battery, a vanadium pentoxide battery, a lithium copper oxide battery, a lithium iron sulfide battery, a lithium bismuth oxide battery, and the like. In addition, as an aqueous battery, an alkaline battery, a manganese battery, a Lucranche battery, a silver oxide battery, a mercury battery, an air zinc battery, and the like can be used.

As the secondary battery, a non-aqueous battery and an aqueous battery can be used. Examples of the non-aqueous battery include a manganese dioxide / lithium battery, a vanadium pentoxide battery, a lithium molybdenum oxide battery, a lithium lithium sulfide battery, a lithium molybdenum sulfide battery, a lithium niobium selenide battery, a carbon lithium battery, and a polymer lithium battery. Aqueous batteries include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-zinc batteries,
It can be used for lead storage batteries.

The required operating pressure of the pressure valve differs depending on the type, shape, size, etc. of these various batteries, but is generally 0.5 to 4 MPa, preferably 1.times.
The operating pressure is set to be 5 to 3 MPa. When the operating pressure is set in the above range, for example, when it is set to 1.5 MPa, the operating pressure can be adjusted to 1.5 ± 0.08 MPa.

[0019]

According to the present invention , connection to a positive electrode or a negative electrode
Conductor layer to be connected to the terminals
Since the sheet-like closing member is fixed so as to cover the through hole provided as a through hole in order to connect the conductor layers of the laminated substrates laminated on both sides, it is possible to keep the operating pressure constant with a simple structure, As a result, safety and reliability can be improved, and the device can be miniaturized and multifunctional by integrating with other elements, and a battery pressure valve that can be easily housed in a small battery can be obtained.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded sectional view showing the battery pressure valve of the embodiment together with other elements, and FIG. 2 is a plan view of the battery pressure valve.

In FIGS. 1 and 2, the pressure valve 1 is provided with a circular sheet-shaped closing member 13 so as to cover one side of a circular through hole 12 formed in a disk-shaped substrate 11.
Has been fixed by. The substrate 11 is a substrate also used as another element, and includes a copper layer 11a, an insulating layer (adhesive layer) from above.
11b and a laminated substrate of an aluminum layer 11c. The through-hole 12 also serves as a through-hole, and a cylindrical conductive layer 11d is fixed around the through-hole, and makes the copper layer 11a and the aluminum layer 11c conductive.

A copper plate is used as the closing member 13, and solder is used as the fixing member 14.
The fixing strength is higher than the breaking strength of No. 3. 1
Reference numeral 5 denotes a positive electrode lead wire connected to the aluminum layer 11c. 16 is a PTC element and 17 is a positive terminal.

The above-described pressure valve is integrated with the PTC element 16 and the positive electrode terminal 17 and housed in a battery to form a battery. In the use state, when the internal pressure of the battery rises due to the occurrence of an overcurrent or an abnormal state, the closing member 13 is broken at the time when the internal pressure of the battery reaches a certain pressure, so that gas inside the through hole 12
The internal pressure is released by leaking through and the accident due to the rupture of the battery is prevented.

Since the closing member 13 is formed in a sheet shape, unlike the concave portion 4 formed by the conventional press working, it is easy to make the thickness of the closing member 13 a constant value. can do. Therefore, the through hole 12
By keeping the size of the pressure member constant and the area receiving the internal pressure of the closing member 13 constant, the operating pressure of the pressure valve 1 can be controlled to a constant value, thereby increasing the safety and reliability. Further, the thickness of the closing member 13 may be changed or the through hole 1 may be changed.
By changing the size of 2, the operating pressure can be set arbitrarily.

The pressure valve 1 described above, is structure of the pressure valve itself because it miniaturization easy <br/> single addition which can easily be accommodated in the battery, constituting in combination with other elements Thereby, the effect of further downsizing can be obtained. That is, in the embodiment, since a multi-layer substrate for another element is used as the substrate 11, the substrate 11 also serves as a pressure valve. In this case, the through-hole of the other substrate 11 can be used as the through-hole 12, whereby the pressure valve 1 can be easily formed to reduce the size of the entire device and accommodate a small battery. become.

[0026] There is no particular limitation on drilling method of through-holes 12 perforating the base plate 11, NC drill, can be carried out by a die punching or the like. Further, the hole diameter of the through hole 12 may be any shape as long as the gas accompanying the increase in the internal pressure of the battery can quickly flow out, and it is sufficient that a space in which the pressure valve is broken can be secured within the range of the convex portion of the positive electrode terminal 17. . The position of the through hole 12 may not be at the center of the substrate 11 and may be decentered depending on the connection state of the battery lead wire or the like.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIG. 1, but the present invention is not limited to these embodiments. In the embodiment, a cylindrical lithium ion secondary battery was used as the battery, and the battery could be incorporated in the battery. The external dimensions of this battery are 17.8 mmφ × 65.0 mm.
It is.

In FIG. 1, the substrate 11 has a thickness of 35 μm.
A through-hole was used as a through-hole 12 using a three-layer substrate in which an m-th copper layer 11a and a 1.0-mm aluminum layer 11c were laminated with an insulating layer 11b made of an adhesive. The substrate 11 has a diameter of 16 mm so that it has the same shape as the positive electrode terminal 17.
To form a through hole 12 having a diameter of 2 mm.
The hole position at this time was within the range of the convex portion of the positive electrode terminal 17 to secure a space where the pressure valve was broken.

Next, a soft copper foil having a thickness of 18 μm
2, the outer shape is processed to a diameter of 3 mm larger than the through hole 12 and smaller than the substrate 11, and is fixed to the substrate 11 by using solder as the fixing member 14 so as to close the through hole 12. It was integrated with the terminal 17 and incorporated into the battery body. The above pressure valve is 1.5 ± 0.1M
It was operated at a pressure of Pa.

As a comparative example, the operating pressure when the cylindrical lithium ion secondary battery 12 used in the above embodiment and the conventional pressure valve shown in FIG. 3 were used was 1.5 ± 0.3 MPa.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a battery pressure valve of an embodiment together with other elements.

FIG. 2 is a plan view of the battery pressure valve of FIG. 1;

FIG. 3 is a plan view of a conventional battery pressure valve.

[Explanation of symbols]

 Reference Signs List 1 pressure valve 2 flange 3 metal plate 4 recess 11 substrate 11a copper layer 11b insulating layer 11c aluminum layer 11d conductive layer 12 through hole 13 closing member 14 fixing member 15 positive lead wire 16 PTC element 17 positive terminal

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-50159 (JP, A) JP-A-5-314959 (JP, A) JP-A-7-254402 (JP, A) JP-A-8- 115715 (JP, A) JP-A-9-223490 (JP, A) JP-A-4-23262 (JP, U) WO 97/30483 (WO, A1) (58) Fields investigated (Int. Cl. ⁷⁾ H01M 2/12 101 H01M 2/34

Claims (2)

(57) [Claims] 1. A conductor layer provided for another element in a battery and connected to a positive electrode or a negative electrode on both sides of an insulating substrate ;
And a laminated substrate on which a conductor layer connected to the terminal is laminated, and provided on the substrate as through holes for conducting the conductor layers on both sides by a conductive layer on the periphery , and provided to detect the pressure inside the battery. And a sheet-like closing member provided so as to cover the through-hole and fixed to the substrate around the through-hole. 2. The battery pressure valve according to claim 1, wherein the closing member is made of a metal foil, and is fixed to the base material by a fixing member.