JPH05205767A - Sealed lead-acid battery - Google Patents

Abstract

PURPOSE:To attain high density in energy by connecting each positive and each negative pole plate to each other where a pole plate lug and a cut-out section are provided for the upper side corners of each rectangular pole plate, providing an exhaust air chamber for a battery jar cover, and concurrently filling inner spaces with acid proof plastic foam in a hermetic type lead battery having powder as a electrolyte supporter. CONSTITUTION:A pole plate lug 2 and a cut-out section 3 are provided for the upper side corner of each rectangular pole plate 1 while the plates are being faced to each other, and when these pole plates 1 are laminated, cut-out sections 4 and 4 matching each pole plate lug 2 and each cut-out section 3 and each separator 6 having a number of projections on its surface, are interposed in between. And next, when the laminated body is made to be a pole plate group 7, a strap 8 having a connecting piece 9 at the place of each pole plate lug 2 and a strap 8' having a pole column 10 at the place of each cut-out section 3 are fitted thereon. In the second place, when this structural body is housed in a battery jar 11, an exhaust air chamber 17 composed of a porous plate 13 which has an exhaust valve 15 in its upper section and is furnished with gas permeability in its lower section, is provided for the cover 20 of the battery jar 11 in advance, acid proof plastic foam which has been foamed, is then filled in spaces built up between powder 18 housed inside and the cover 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved sealed lead acid battery.

[0002]

2. Description of the Related Art There are two types of sealed lead-acid batteries, a retainer type and a gel type, in which a negative electrode absorbs oxygen gas generated during battery charging. The retainer type inserts a mat-shaped separator (glass separator) mainly composed of fine glass fibers between the positive electrode plate and the negative electrode plate, which holds the sulfuric acid electrolyte necessary for discharge and separates both electrodes. In recent years, it has been widely used as a backup power source for portable devices and computers by taking advantage of its features such as no maintenance, no leakage, and position-free.

However, the glass separator is made of a fine glass fiber having a diameter of about 1 micron manufactured by a special method into a mat, and is considerably expensive as compared with a commonly used lead-acid battery separator. Moreover, in order to obtain stable battery performance, the electrode plate group must be strongly pressed and assembled, which makes it difficult to assemble the battery, which inevitably increases the manufacturing cost of the battery.

Further, the sulfuric acid electrolytic solution can be held only by the glass separator inserted between the positive and negative electrode plates, and the electrolytic solution is placed around the electrode plate group like an open type lead acid battery. Since the batteries cannot be arranged, the battery reaction is limited by the amount of the electrolytic solution, and the battery performance is inferior to that of the liquid battery.

On the other hand, the gel type is less expensive than the retainer type, but the battery performance is inferior to the retainer type sealed lead acid battery,
There is a drawback that the life performance is not good because the electrolyte separates from the sulfuric acid gel during use.

In order to solve these drawbacks, therefore, there has been proposed a sealed lead-acid battery which is neither a retainer type using fine glass fibers nor a gel type using a gel electrolyte. That is, a powder having a high porosity and a large specific surface area, for example, silica powder, is used as the electrolyte holding material, and the above powder is filled in the gap between the positive electrode plate and the negative electrode plate and around the electrode plate group. It is a sealed lead-acid battery with a configuration.
Silica powder is an inexpensive material that is mass produced and sold, and because it has excellent acid resistance and electrolyte retention, it is an excellent powder for use as an electrolyte retention material for this type of sealed lead-acid battery. It can be said to be a material. However, the sealed lead-acid battery using such powder as an electrolyte holder has the following problems.

That is, when a powder of a monoblock type battery composed of a plurality of cells is filled, it is convenient to make the filling amount constant because the filling of the powder is easier and the liquid injection amount can be made constant. It is good, however, because the internal volume of the battery case is different for each cell, the filling amount is not constant when the powder is filled in the battery container. However, when a certain amount of powder is filled in each cell, a space is inevitably formed in the upper part of the battery case. If a space is created in the battery, the powder moves during the liquid injection or the initial charge, and a cavity is created in the powder layer filled between the electrode plates, so that the expected battery performance cannot be obtained.

Therefore, for example, it has been attempted to foam a synthetic resin and fill the space in the battery with an open-cell plastic foam to fix the powder so that the powder does not move. Since a layer was formed and the air permeability was lost, and the powder filled in the battery could not communicate with the outside, it was impossible to inject liquid, and the battery could not be constructed.

In addition to backup power sources for portable equipment and various equipment, compact sealed lead acid batteries with high energy density are desired for all purposes such as power sources for automobiles and electric vehicles. The conventional sealed lead-acid battery has a lot of wasted space, and there is a limit to the compact structure.

[0010]

According to the present invention, powder is filled in the gap between the positive electrode plate and the negative electrode plate and around the electrode plate group, and the sulfuric acid electrolytic solution is substantially impregnated in the powder and electrode plate group. It is a sealed lead-acid battery that is held, and the positive and negative plates have a shape in which one corner of the rectangular electrode plate has an electrode ear and the other corner has a notch, and the strap is formed by welding the electrode ear. An inter-cell connecting piece that does not project from the electrode plate surface is provided, and the electrode plate groups of adjacent cells are connected to each other by the partition wall penetrating method through the inter-cell connecting piece, and the battery case lid portion has an exhaust valve at the top. An exhaust chamber with a breathable perforated plate is provided at the bottom, the lower end of the perforated plate is provided close to the upper end of the electrode plate group, and the porous plate is placed so that it is just buried in the packed powder layer. In the space formed between the powder layer and the back of the battery case lid, foamed acid-resistant plastic foam is used. By configured to full, it is to provide a compact sealed lead batteries to eliminate the wasted space.

[0011]

EXAMPLES The present invention will be described below based on examples.

The present invention uses an electrode plate 1 having a shape as shown in FIG. 1, 2 is an electrode plate ear provided at one corner of the electrode plate 1, and 3 is a notch provided at another corner. is there. The positive / negative electrode plate having such a shape and the separator plate 6 shown in FIG. 3 using the separator 6 having the notches 4 and 4 ′ in the portion located at the electrode plate ear as shown in FIG. To make. In addition, separate
The protrusion 6 is used as the tag 6, and the protrusion is made of a resin that has acid resistance and oxidation resistance and does not elute substances harmful to the lead storage battery.

In FIG. 3, 8 and 8'denotes straps formed by welding the ears 2 of a plurality of polar plates. Strap 8
The connecting pieces 9 between the cells are formed integrally with the strap in the electrode plate group for the end cells. FIG. 4 shows a sealed lead-acid battery according to the present invention assembled using the electrode plate group thus manufactured. The electrode plate group 7 is inserted into the battery case 11, and is connected to the electrode plate groups of the adjacent cells via the inter-cell connecting piece 9 of the electrode plate group by the partition wall penetration method.

After that, the battery case 11 and the battery case lid 12 are welded, and the pole 10 is welded to the terminal 14. Reference numeral 16 is an exhaust plug attached to the battery case lid, and an exhaust valve 15 is provided therein. The battery case lid is provided with a gas permeable porous plate 13 at a position below the exhaust valve 15 and close to the upper end of the electrode plate group 7. By closing the perimeter, the exhaust valve is provided on the upper side and the porous plate is provided on the lower side. An exhaust chamber 17 having the is formed.

Then, the powder 18 having high porosity and large surface area is filled in the gap between the positive electrode plate and the negative electrode plate and around the electrode plate group while applying vibration from the powder filling port 19. At this time, the amount of powder to be filled is adjusted so that the porous plate 13 is just buried, and a fixed amount is filled in each cell. Since this powder has a high porosity and a large surface area, a large amount of electrolyte can be strongly retained. Silica powder was used in this example.

When the powder filling is completed, an acid-resistant foaming synthetic resin is injected from the powder filling port 19, sealed with a lid 20, and then foamed to form a powder layer and a lid back. The space formed therebetween is filled with the plastic foam 21 to fix the powder layer. As the acid resistant resin capable of foaming, for example, a foamed phenol resin, particularly a room temperature foaming type two-component mixed type phenolic resin, which is easy to foam and has excellent acid resistance, heat resistance and mechanical strength. convenient.

Since the skin layer is always formed on the surface of any plastic foam when it is foamed, if the porous plate 13 is not buried in the powder layer, the surface of the porous plate is covered with the skin layer and the air permeability is improved. It will be lost and you will not be able to achieve your purpose. This is the reason why the porous plate 13 is embedded in the powder layer. Therefore, the plastic foam used does not necessarily have to be open cells, and polyethylene or polystyrene may be used as long as it is a foaming resin having acid resistance, heat resistance, mechanical strength, and the like.

Battery case lid 12 and perforated plate 13 having open cells
Since the perimeter is closed by the wall surface hanging down from the battery case lid, the exhaust chamber 17 contains gas and electrolytic solution but does not contain powder.

Next, a sealed lead acid battery according to the present invention was actually manufactured and its performance was compared with that of a conventional product. A grid cast by using a lead-calcium alloy was filled with a storage battery paste prepared by a conventional method to produce positive and negative electrode plates having the shape shown in FIG. Then, positive and negative plates are alternately stacked by using a separator having a projection on a part of the shape shown in FIG. 2, the electrode ears are welded, and then inserted into a battery case to connect the cells, and then to close the lid. The 36B20 type sealed lead acid battery for automobiles was completed by welding. The outer diameter of the obtained battery was 13.0 cm in width, 20.0 cm in length, and 13.5 cm in box height. On the other hand, the conventional sealed lead-acid battery has the same width and length, but the box height is 20 cm, which is a battery compact about 30%.

When initially charging the battery assembled in this manner, the exhaust valve 15 is first removed and a predetermined amount of sulfuric acid electrolyte is injected. As described above, since the lower end of the perforated plate 13 is provided close to the upper end of the electrode plate group, the injected electrolyte passes through the perforated plate 13 and the positive electrode group immediately below the electrode plate group,
The solution is absorbed in a short time because it is absorbed by the negative electrode plate and the separator and spreads around. Do the initial charging with the exhaust plug attached. Although the electrolyte surface rises by gassing during charging, the electrolyte surface is trapped in the exhaust chamber 17, so that the electrolyte solution does not leak to the outside even if the overflow prevention jig is not mounted as in the conventional case.

Next, initial charge was performed and the 5-hour rate capacity was determined. It was found that both the battery according to the present invention and the conventional battery had a capacity of about 27 Ah
Although there was no difference, the high rate discharge capacity at low temperature was about 10
%, And the voltage at the 5th second was higher by about 0.3 V. This is because the cell-to-cell connecting portion had conventionally protruded from the electrode plate surface,
In the product of the present invention, not to protrude from the electrode plate surface,
This is probably because the height of the battery was considerably lowered and the poles were also shortened, which reduced the voltage drop at these connecting portions and poles.

[0022]

As described above in detail, according to the present invention, it is possible to make a battery smaller in size, have a high energy density and prevent overflow during charging, as compared with the conventional battery, and its industrial value. Is very large.

[Brief description of drawings]

FIG. 1 is a schematic view showing the shape of an electrode plate used for implementing the present invention.

FIG. 2 is a schematic view showing the shape of a separator used for carrying out the present invention.

FIG. 3 is a perspective view showing an outline of an electrode plate group.

FIG. 4 is a cross-sectional view of essential parts showing a sealed lead-acid battery according to the present invention.

[Explanation of symbols]

 1 electrode plate 2 electrode plate ear 3 notch part 4,4 'notch part 5 protrusion part 6 separator 7 electrode plate group 8,8' strap 9 cell connecting piece 11 battery case 12 battery case lid 13 porous plate 15 exhaust Valve 17 Exhaust chamber 18 Powder 19 Powder filling port 20 Lid 21 Plastic foam

Claims (1)

[Claims] 1. A powder having a high porosity and a large specific surface area is filled in the gap between the positive electrode plate and the negative electrode plate and around the electrode plate group, and a sulfuric acid electrolytic solution in an amount sufficient and sufficient for charging and discharging a battery is substantially used. A sealed lead-acid battery in which the powder and the electrode plate group are impregnated and held, wherein the positive and negative electrode plates have a shape in which a polar plate ear is provided at one corner and a notch portion is provided at another corner. , A strap formed by welding the electrode tab ears is provided with an inter-cell connecting piece that does not protrude from the electrode plate surface, and the electrode plate groups of adjacent cells are connected to each other by the partition wall penetrating method via the inter-cell connecting piece. The battery container lid portion has an exhaust valve in the upper part and an exhaust chamber having a breathable porous plate in the lower part, and the lower end of the porous plate is provided close to the upper end of the electrode plate group. With positive,
The porous plate is arranged so that it is just buried in the powder layer filled between the negative electrode plates and around the electrode plate group, and the space formed between the powder layer and the back of the battery case lid is foamed acid resistant. Sealed lead-acid battery filled with flexible plastic foam.