JP3060838B2 - Explosion-proof battery structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an explosion-proof battery structure of a battery cell, and more particularly to an explosion-proof battery structure of a battery pack using a plurality of battery cells connected in series.

[0002]

2. Description of the Related Art In general, a driving voltage of a CPU built in a small portable telephone is 3 V. However, in order to secure continuous talk time, a battery of a recent small portable telephone is as follows.
There is a tendency to use battery packs in which three 1.2 V nickel-cadmium storage batteries are connected in series.

When a small portable telephone is used in an explosion-hazardous area, the above-described battery pack is used as shown in FIG.
(B) In a state as shown in the figure, the battery pack is usually housed together with a current limiting circuit board in a battery pack case (not shown). That is, the battery cells A1, A2, A3 composed of a 1.2V nickel-cadmium storage battery or the like are placed in a close parallel relationship with the adjacent battery cells A1, A2, A3 reversed in polarity. A1, A2, A
The positive electrode a1 and the negative electrode a2 are connected by a connecting electrode plate B to form an assembled battery, and a positive electrode plate C and a negative electrode plate D are attached to the ends of the battery pack.

Therefore, in such an assembled battery pack, the discharge distance between the electrodes and the like is maintained by the insulating coating of each of the battery cells A ₁ , A ₂ , A ₃ , and the distance between the assembled battery pack and the peripheral device is maintained. Is insulated by a battery pack case made of an insulating resin.

[0005]

By the way, in the recent explosion-proof certification test, even if the electrodes of the battery pack are short-circuited, the surface temperature of each of the battery cells A ₁ , A ₂ , A ₃ rises above a certain temperature. Requirements, such as ensuring that the creepage discharge distances of the battery cells A ₁ , A ₂ , and A ₃ constituting the battery pack are sufficient, and separating the individual battery cells A ₁ , A ₂ , and A ₃ from each other. is there. However, as mentioned earlier
In conventional battery packs such as those described above, if the entire battery pack is coated with an insulating resin such as epoxy resin, the abnormal surface temperature rises during a short-circuit test, and there is no gas permeability from the battery gas valve. There was a risk of battery explosion due to internal gas, and there was a problem that it was not possible to ensure a creepage distance within the standard between the electrodes of the bar batteries A ₁ , A ₂ and A ₃ .

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the conventional explosion-proof battery structure, the object of the present invention is to prevent the surface temperature from rising abnormally during a short-circuit test and to discharge gas from a battery gas valve to the outside. An object of the present invention is to provide an explosion-proof battery structure that can sufficiently secure a creepage discharge distance and a separation distance of a bar battery.

[0007]

In order to achieve this object, the present invention relates to a method of connecting a plurality of adjacent uncoated bar cells in series with their polarities reversed, and connecting the cell cells in series. In an explosion-proof battery structure in which a coated rod battery is an assembled battery pack covered with an insulating envelope, a CT is inserted between each uncoated rod battery.
I: A silicon rubber enclosure which is interposed by 90 or more insulating spacers and is kept at a specific distance that does not cause a physical short circuit between the battery cells, and covers the entire battery cells and the insulating spacers. The present invention proposes an explosion-proof battery structure.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in detail with reference to FIGS. FIG. 1 shows a small-sized mobile phone to which the present invention is applied. The small-sized mobile phone includes a telephone body 1 having a dial button 1a, a function button 1b, and the like, and a battery pack case 2 as a power adapter inserted into the telephone body 1. It has.

The battery pack case 2 shown in FIGS. 6 and 7 has a front case 3 and a rear case 4 which are injection-molded with an insulating resin, respectively. Inside the front case 3 and the rear case 4, details are provided. A battery pack 5 and a current limiting circuit unit 6 of the present invention described below are built in. In other words, the current limiting circuit unit 6, which is entirely coated with an epoxy resin in order to enhance insulation, has a sufficient distance L between terminals.
The positive electrode plate 7 and the negative electrode plate 8 of the battery pack 5 maintaining ₁ are connected via the lead wires 9 and 10, and the output side lead wires 11 and 12 of the current limiting circuit unit 6 are described above. The output contact 13 electrically connected to the telephone body 1 is connected.

FIGS. 2 to 4 show an assembled battery pack 5 according to the present invention. In this embodiment, three rod batteries 141 and 14 each composed of a nickel-cadmium storage battery of 1.2 V are used.
2, 143 are used. That is, these stick batteries 141
, 142 and 143 are provided with a positive pole 14a and a negative pole 14b at both end surfaces thereof.
And the negative pole 14b are adjacent to the bar batteries 141, 14
2 and 143 are reversed in polarity.
, 142, 143, the insulating spacers 151, made of an insulating plastic having a thickness of 90 or more in terms of electrical aging characteristic tracking index (CTI).
The battery 152 is integrated with the connecting electrode plate 16 in a state where the battery 152 is interposed between the battery cells 141, 142 and 143. In other words, the positive pole 14 of the adjacent rod batteries 141, 142, 143
a and the negative electrode 14b are electrically connected to each other.
6 are spot-welded to the corresponding positive and negative poles 14a and 14b, respectively, as shown in FIG.
, 142, 143 and the insulating spacers 151, 152 are physically integrated.

Further, although the base 8a of the negative electrode plate 8 is solder welded to the negative electrode 14b of the right rod cell 14 ₃ of FIG. 3, the negative electrode plate 8 bar battery 14 _1, 14
_2, 14 towards ₃ the alignment direction ahead of the extended leads 10 are soldered to the connecting end 8b. Then, the base portion 7a of the positive electrode plate 7 is solder welded on the left side of the rod cell 14 ₁ of the positive electrode 14a of FIG. 3, the rod cell 14 ₁ from the negative electrode plate 8, 14 _2, 14 ₃ in the lengthwise direction The connection end 7b of the positive electrode plate 7 which is sufficiently separated is to be soldered to the lead wire 9 described above.

The entire battery pack 5 described above, that is, the portion other than the connection ends of the positive electrode plate 7 and the negative electrode plate 8 is C
TI: The battery pack 5 covered with the gas-permeable silicon rubber enclosure 17 having an insulating property of 90 or more and insulated by the silicon rubber enclosure 17 is incorporated into the battery pack case 2. FIG. 5 shows the silicon rubber enclosure 1
7 shows a step of covering the battery pack 5 with the connecting electrode plate 1.
A plurality of rod batteries 14 ₁ , 14 ₂ , 1 integrated in 6
4 ₃ connecting end 7 of the positive electrode plate 7 and the negative electrode plate 8
With the b and 8b facing upward, they are dropped into the cavity 18a of the mold 18 and silicon resin is injected and solidified into the cavity 18a. Therefore, by using such a mold 18, it is possible to easily manufacture the battery pack 5 as shown in the drawing in which the inner dimensions of the battery pack case 2 are matched and the whole is covered with the silicone rubber enclosure 17.

Since the battery pack 5 according to the illustrated embodiment has the above structure, it can satisfy all explosion-proof conditions required for an explosion-proof battery structure. Even when the short test was performed, the temperature of the surface of the battery pack 5 did not rise abnormally. The reason for this is that the gas generated inside each of the battery cells 141, 142, 143 flows out to the outside due to the heat radiation of the silicone resin itself, so that the battery cells 141, 142,
This is probably because the surface temperature of 143 and the silicon rubber enclosure 17 is kept normal. From the viewpoint of creeping discharge, the point that the positive electrode plate 7 and the negative electrode plate 8 are kept at a sufficient distance from each other, and that the insulating spacers 151, 1
Since the battery cells 141, 142, and 143 are separated from each other by 52, the creeping discharge voltage increases, and short-circuiting does not occur easily. Of course, since the entire battery pack 5 is covered with the silicon rubber enclosure 17, the insulating properties of the entire battery pack are sufficient, and the separation distance (discharge interval) and creepage distance of the explosion-proof standard are about 1/3 or less. Indicated.

[0014]

As is apparent from the above description, according to the present invention, the entire cell is covered with the silicon rubber enclosure by interposing an insulating spacer between the cells constituting the battery pack. Therefore, the temperature rise during the short test is small,
This has the effect of achieving an explosion-proof battery structure having excellent surface discharge and remote discharge characteristics.

[0015]

[0016]

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a small mobile phone embodying the present invention.

FIG. 2 is a partially cutaway side view of the battery pack according to the present invention.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is a sectional view of a positive electrode portion of the battery pack.

FIG. 5 is an explanatory diagram of a molding step of the battery pack.

FIG. 6 is a sectional view of a battery pack case according to the present invention.

FIG. 7 is a sectional view taken along line 7-7 in FIG. 6;

8 (a) and 8 (b) are an end view and a side view of a conventional explosion-proof battery pack.

[Explanation of symbols]

 5, 5A battery pack 7 plus electrode plate 8 minus electrode plate 141 to 143, 14A1 to 14A3 stick battery 14a plus electrode 14b minus electrode 151, 152 insulating spacer 17 silicon rubber enclosure

Claims (1)

(57) [Claims] 1. A battery pack in which a plurality of adjacent uncoated bar batteries are connected in series with the polarity of the uncoated bar batteries reversed, and the uncoated bar batteries are covered with an insulating enclosure. Explosion-proof battery structure, the CT between each uncoated rod battery
I: A silicon rubber enclosure which is interposed by 90 or more insulating spacers and is kept at a specific distance that does not cause a physical short circuit between the battery cells, and covers the entire battery cells and the insulating spacers. Explosion-proof battery structure.