JPH10199546A - Thermal cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal cell which can surely prevent a connection fixed part from directly contacting with a cell cover and a cell case and forming a short circuit by shielding by a lead insulating member even if the connection fixed part is externally expanded when the cell cover is pushed in an upper end opening of the cell case. SOLUTION: A lead insulating member 13 of natural mica and the like is arranged in a space of an upper cell cover 7 of a connection fixed part 10 connected and fixed an upper end part of a side lead 6 connected to a collector plate of respective unit cells 2 of a power unit 1 and an upper lead 9 connected to a cover terminal 8 of the cell cover 7 or in a space of a cell case 11 at outer periphery side of this connection fixed part 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal battery using, as an electrolyte, an inorganic salt which becomes conductive when heated and melted.

[0002]

2. Description of the Related Art A thermal battery is a primary battery which uses an inorganic salt which is an electrically conductive solid at room temperature during storage and which becomes conductive when heated to a high temperature by heating and melting when used. It has the feature that it can store a large current in a short time and is used as a power source for emergency use.

As shown in FIG. 5, a power generating unit 1 for a thermal battery has a disk-shaped upper heat insulating material 4 and a lower heat insulating material 4 at the upper and lower ends where a plurality of disk-shaped unit cells 2 and a plurality of heating elements 3 are alternately stacked. The material 5 is arranged. Each unit cell 2 is a battery cell having a structure in which an electrolyte that becomes conductive at a high temperature is sandwiched between positive and negative electrodes, and a current collector is connected to each of the positive and negative electrodes. Each heating element 3 burns and generates heat when the thermal battery is used, so that these unit cells 2 are heated and activated. The upper heat insulating material 4 is provided with six notched portions 4a from above at equal intervals on a disk-shaped peripheral portion. Also, on the side of the power generation unit 1,
Six side leads 6 are arranged along the six cutouts 4 a of the upper heat insulating material 4. These side leads 6 are respectively connected to either the positive or negative current collector plate of each unit cell 2, and the upper end protrudes above the power generation unit 1.

[0006] As shown in FIG. 6, a disk-shaped battery cover 7 is disposed above the power generation unit 1. The battery cover 7 is provided with six pin-shaped cover terminals 8 which are penetrated through the disk-shaped front and back surfaces and are insulated and sealed at equal intervals. One end of an upper lead 9 is connected and fixed to each of lower ends of these cover terminals 8 projecting to the lower surface side of the battery cover 7 by spot welding.
The other ends of the upper leads 9 are connected and fixed to the upper ends of the side leads 6 by spot welding, respectively, and unnecessary portions of the connection fixing portions 10 are cut and then bent and wound.

The power generation unit 1 is housed in a cylindrical battery case 11. Then, by fitting the upper battery cover 7 into the upper end opening of the power generation unit 1,
This upper end opening is closed and sealed and fixed by Tig welding. At this time, the lower end portion of the cover terminal 8, the upper lead 9, and the connection fixing portion 10 are respectively arranged in the cutout portions 4 a of the upper heat insulating material 4 in the power generation unit 1. The inner peripheral surface of the battery case 11 is provided with a case insulating material 1 in order to avoid contact with the housed power generation unit 1 and the side leads 6.
2 are arranged.

[0006]

However, the battery cover 7 is arranged above the power generation unit 1 so that each upper lead 9
Is spot-welded to the upper end of the side lead 6 or when the unnecessary portion of the connection fixing portion 10 is cut and bent and wound around by this spot welding, the battery cover 7 It must be arranged at a position higher than the height of the vehicle to secure a space for performing these operations. For this reason, the power generation unit 1
Since the battery cover 7 does not completely fit into the upper end opening even if the battery cover 7 is accommodated in the battery case 11, it is necessary to press the battery cover 7 from above and push it to the original height position with respect to the power generation unit 1. However, when the battery cover 7 is pushed in at the time of assembling the thermal battery, the upper lead 9 is also pushed, so that the connection fixing portion 10 with the side lead 6 spreads outward, and the battery cover 7 and the battery case 1
There is a risk of contact with the first weld. Then, when the connection fixing portion 10 comes into contact with the welding portion, the heat at the time of Tig welding burns out the insulating tape stuck for insulating the leads 6 and 9, and the connection fixing portion 10 forms the battery cover 7 or the battery case. 11 to form a short circuit. In addition, when the connection fixing portion 10 spreads outward, the insulating tape is peeled off even when the connection fixing portion 10 is caught between the upper end opening of the battery case 11 and the battery cover 7 fitted therein, so that the battery cover 7 or the battery There is a problem that a short circuit is formed via the case 11.

The present invention has been made in view of such circumstances, and by arranging a lead insulating material on an outer peripheral side of a connection fixing portion in which a side lead and an upper lead are connected and fixed, the leads are covered with a battery cover. It is an object of the present invention to provide a thermal battery that can prevent a short circuit from being formed by contact with a battery or a battery case.

[0008]

That is, in order to solve the above-mentioned problems, the present invention provides a side lead connected to a current collector plate of each unit cell on a side surface of a power generation unit in which a unit cell and a heating element are stacked. While arranging, the other end of the upper lead whose one end is connected to the cover terminal provided on the battery cover arranged above the power generation unit is connected and fixed to the upper end of the side lead, and this power generation unit is Housed in the battery case,
In the thermal battery whose upper end opening is closed by the battery cover, at least between the battery case on the outer peripheral side of the connection fixing portion between the upper end of the side lead and the other end of the upper lead,
In addition, a lead insulating material having heat resistance and insulating properties is arranged between the connection fixing portion and the battery cover.

According to the above means, the lead insulating material is arranged on the outer peripheral side of the connection fixing portion between the side lead and the upper lead. Therefore, when the battery cover is pushed into the upper end opening of the battery case, the connection fixing portion is moved outward. Even if it spreads, it will come into contact with the battery cover and battery case with this lead insulating material in between, and it will be affected by welding heat or be caught between the battery cover and battery case. Disappears. Therefore, the thermal battery of the present invention can reliably prevent a short circuit from being formed due to the connection and fixing portion between the upper lead and the side lead coming into direct contact with the battery cover or the battery case.

[0010]

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

1 to 4 show an embodiment of the present invention. FIG. 1 is a partial perspective view showing a power generation unit accommodated in a battery case, and FIG. 2 is a structure of each unit cell of the power generation unit. FIG. 3 is a partial longitudinal sectional view for explaining a connection structure between a power generation unit and a battery cover, and FIG. 4 is a partial longitudinal sectional view for explaining a structure of a thermal battery. Components having the same functions as those of the conventional example shown in FIGS. 5 and 6 are denoted by the same reference numerals.

The power generating unit 1 of the thermal battery according to the present embodiment has a disk-shaped upper part and a disk-shaped upper part formed by alternately laminating a plurality of disk-shaped unit cells 2 and a plurality of heating elements 3 as shown in FIG. The case where the heat insulating material 4 and the lower heat insulating material 5 are arranged will be described. Each unit cell 2 has an electrolyte 2a as shown in FIG.
Is sandwiched between the positive electrode active material 2b and the negative electrode active material 2c, and current collector plates 2d and 2 are provided on both end surfaces of the positive electrode active material 2b and the negative electrode active material 2c.
e is a battery cell having a structure in which e is arranged. Electrolyte 2a
Is a solid having no conductivity at normal temperature and mainly composed of an inorganic salt which becomes conductive when melted at a high temperature under heating. The positive electrode active material 2b is mainly composed of iron disulfide or the like, and the negative electrode active material 2c is mainly composed of a lithium alloy such as a lithium aluminum alloy or a lithium silicon alloy. Each heating element 3 burns when the thermal battery is used, and
Is activated by heating Zr / BaCrO4
Sheet-like exothermic agent made by fusing a series of exothermic agents together with inorganic fibers or F
An e / KClO 4 -based exothermic agent may be used in the form of a pellet-shaped exothermic agent formed by pressing. The thermal battery uses a igniting material to ignite these heating elements 3, but in the present embodiment, illustration and description of the igniting material are omitted for simplicity. In the present invention, the configuration of each unit cell 2 of the thermal battery, the composition of each heating element 3 and the like are arbitrary, and are not limited to those of the present embodiment.

The upper heat insulator 4 and the lower heat insulator 5 are both disc-shaped heat insulators made of ceramic board, mica, or the like. As shown in FIG. Are provided with six notched portions 4a from above at equal intervals. Also, on the side surface of the power generation unit 1, along the six cutouts 4 a of the upper heat insulating material 4,
Six side leads 6 are arranged. These side leads 6 are respectively connected to either the positive or negative current collector plate 2 d or the current collector plate 2 e of each unit cell 2 shown in FIG. 2, and the upper end protrudes above the power generation unit 1.

As shown in FIG. 3, the upper end of each side lead 6 of the power generating unit 1 is connected to each cover terminal 8 of the battery cover 7 via the upper lead 9. That is, the disk-shaped battery cover 7 is provided with six pin-shaped cover terminals 8 penetrating through the front and back surfaces and insulated and sealed at equal intervals, and these cover terminals 8 are provided on the lower surface side of the battery cover 7. One end of the upper lead 9 is connected and fixed to each of the protruding lower ends by spot welding. The other ends of the upper leads 9 are connected and fixed to the upper ends of the side leads 6 by spot welding, and unnecessary portions of the connection fixing portions 10 are cut and then bent and wound. Further, each connection fixing part 10 is provided with a cover terminal 8.
Together with the lower end portion of the upper heat insulating material 4 and the upper lead 9 in the cutout portion 4a of the upper heat insulator 4 in the power generation unit 1. However, in order to perform these operations, the battery cover 7 is arranged at a position higher than the original height position above the power generation unit 1, and a work space is secured between the battery cover 7 and the power generation unit 1. In addition, the upper lead 9 becomes oblique because of this.

The power generation unit 1 is housed in a cylindrical battery case 11 as shown in FIG. On this occasion,
The lead insulating material 13 is provided on the connection fixing portion 10 arranged in the space within each cutout portion 4a of the upper heat insulating material 4.
Place. Each of the lead insulating materials 13 is formed by attaching a heat-resistant tape to a plate having heat resistance and insulation properties such as natural mica and bending the same at a right angle. Each of the lead insulating materials 13 is wider than the leads 6 and 9 and the connection fixing portion 10 and is smaller than the opening width of the cutout portion 4a. Each of the lead insulating materials 13 has a horizontal portion inserted into the cutout portion 4a and is disposed on the connection fixing portion 10, and a vertical portion is disposed below the outer peripheral side of the connection fixing portion 10. Therefore, the power generation unit 1 is
When the lead insulating material 1 is accommodated in the battery case, the lead insulating material 1 is located between the connection fixing portion 10 and the battery cover 7 above and the connection fixing portion 10 and the battery case 11 on the outer peripheral side of the upper end of the side lead 6.
3 will intervene. The case insulating material 12 is arranged on the inner peripheral surface of the battery case 11 as in the conventional case.

When the power generation unit 1 is accommodated in the battery case 11, the battery cover 7 is pressed from above and fitted into the upper end opening of the battery case 11, as shown in FIG. Then, the battery cover 7 is sealed and fixed to the upper end opening of the battery case 11 by Tig welding.
1 to complete the thermal battery. At this time, when the battery cover 7 is pushed into the upper end opening of the battery case 11, the oblique upper lead 9 in each notch 4a returns to a horizontal position, so that the connection fixing portion 10 is pushed outward and spreads. There is. However, even if the connection fixing portion 10 spreads outward and protrudes from the cutout portion 4a, the lead insulating material 13 intervenes, so that the connection fixing portion 10 directly contacts the battery cover 7 or the battery case 11. It does not happen. Further, when the connection fixing portion 10 spreads outward, the lead insulating material 13 becomes the battery cover 7 and the battery case 11.
And the connection fixing portion 10 does not get caught between the battery cover 7 and the battery case 11. Furthermore, heat during Tig welding also
Since it is cut off by the lead insulating material 13, it is not transmitted directly to the connection fixing portion 10.

As described above, in the thermal battery of the present embodiment, by disposing the lead insulating material 13 on the outer peripheral side of each connection fixing portion 10 connecting the side lead 6 and the upper lead 9, each of these connection fixing The part 10 directly contacts the battery cover 7 or the battery case 11 or the battery cover 7 and the battery case 1
As a result, the formation of a short circuit can be reliably prevented.

In the above embodiment, the lead insulating material 1
Although the case where 3 is arranged only above the connection fixing portion 10 and the outer peripheral side of the connection fixing portion 10 and the upper end of the side lead 6 has been described, it can be arranged in a wider range. In the above embodiment, the case where the connection fixing portion 10 is formed by spot welding the side lead 6 and the upper lead 9 to cut and bend unnecessary portions has been described. The connection fixing method is arbitrary.

Further, in the above-described embodiment, the case where six side leads 6 are arranged on the side of the power generation unit 1 and these side leads 6 are connected to the six cover terminals 8 via the upper leads 9 will be described. However, these side leads 6
And the number of the cover terminals 8 and the like can be appropriately changed.
Further, in the above-described embodiment, the case where the cutout portion 4a is provided in the upper heat insulating material 4 of the power generation unit 1 and the connection fixing portion 10 is disposed here has been described. Whether to provide the upper heat insulating material 4 and the lower heat insulating material 5 is optional.

[0020]

As is apparent from the above description, according to the thermal battery of the present invention, when the battery cover is pushed into the upper end opening of the battery case, the connection fixing portion between the side lead and the upper lead spreads outward. Even so, since the lead insulating material having heat resistance and insulation is interposed, it is possible to reliably prevent the connection and fixing portion from directly contacting the battery cover or the battery case and forming a short circuit. .

[Brief description of the drawings]

FIG. 1, showing an embodiment of the present invention, is a partial perspective view when a power generation unit is housed in a battery case.

FIG. 2, showing one embodiment of the present invention, is a longitudinal sectional perspective view for explaining the structure of each unit cell of a power generation unit.

FIG. 3 illustrates one embodiment of the present invention, and is a partial longitudinal sectional view illustrating a connection structure between a power generation unit and a battery cover.

FIG. 4, showing one embodiment of the present invention, is a partial vertical cross-sectional view illustrating the structure of a thermal battery.

FIG. 5 is a perspective view for explaining a structure of a power generation unit of the thermal battery.

FIG. 6 shows a conventional example, and is a partial longitudinal sectional view for explaining the structure of a thermal battery.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power generation unit 2 Unit cell 3 Heating element 6 Side lead 7 Battery cover 8 Cover terminal 9 Upper lead 10 Connection fixing part 11 Battery case 13 Lead insulating material

Claims (1)

[Claims] 1. A side surface lead connected to a current collector plate of each unit cell is disposed on a side surface of a power generation unit in which unit cells and a heating element are stacked, and is provided on a battery cover disposed above the power generation unit. The other end of the upper lead, one end of which is connected to the cover terminal, is connected and fixed to the upper end of the side lead, the power generation unit is housed in the battery case, and the upper end opening is closed by the battery cover. At least between the upper end of the side lead and the other end of the upper lead, between the battery case on the outer peripheral side of the connection fixing portion, and the battery cover above the connection fixing portion, and has heat resistance and insulation. A thermal battery in which a lead insulating material having a property is disposed.