JPS5827475Y2 - lead acid battery - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a lead-acid battery in which a plurality of adjacent cell plate groups are connected at both the upper and lower portions through a partition wall of a battery case.

Conventional lead-acid batteries connect adjacent cells via partition walls using a partition-through type connector that is integrally installed above the electrode plate group inserted into each battery chamber, and It is customary for the lower part to be fixed slightly above the bottom of the container by means of a clamp.

In such a structure, the electromotive reaction of the positive and negative picture electrode plates mainly takes place in the upper part of the electrode plate where the connecting body is provided, and only this part of the active material participates in the electromotive reaction, so that The utilization rate of the active material and the current density of the sheet metal body are low, and a sufficient electromotive reaction cannot be expected. Therefore, the achievement of high output per unit weight and high battery capacity has not been fully satisfactory.

In order to achieve high output per unit quantity and high battery capacity, a method was proposed in which both the upper and lower parts of the electrode plate group are connected to the electrode group of adjacent cells.

Compared to a method in which the electrode plate group of an adjacent cell is connected only to the top of the electrode plate group, this method has two connection points, one above the other, and the voltage drop at the connection point can be reduced compared to previous methods. This has the advantage of increasing the utilization rate of the active material in the electrode sheet metal body and substantially equalizing the current density.

However, although this advantage exists, since there is a connecting part between the positive and negative electrodes at the bottom of the electrode plate group, a short circuit between the positive and negative electrode connections occurs due to the accumulation of fallen active material, which shortens the battery life. There was a problem of lowering the

Therefore, it is a major issue to prevent internal short circuits at the bottom of the electrode plate group caused by this fallen active material, and some proposals have been made to provide a partition piece or the like in the bottom cover to partition the bottom connection body part. However, the width of the partition piece that can be formed on the lower lid cannot be made sufficiently wide because the lower lid is integrated with the middle frame, so it is necessary to separate the fallen active material by partitioning it into left and right sides. A sufficient partitioning effect could not be obtained.

This invention solves these problems of conventional lead-acid batteries.
A width of 5Qm protruding perpendicularly to the partition wall at the bottom of each battery compartment in the middle frame.
This problem was solved by providing a partition piece with a diameter of less than m and fixing it to the bottom cover, which improved battery performance, and also sufficiently improved the effect of preventing internal short circuits at the bottom of the electrode group. be.

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

In the drawings, reference numeral 1 denotes a battery case made of synthetic resin, for example polypropylene, and this battery case has a rectangular cylindrical resin inner frame 3 which has openings at the top and bottom and is partitioned into a plurality of battery chambers by a plurality of partition walls 2; It is constructed by fixing together an upper lid 4 made of the same material that covers the upper opening and a lower lid 5 that covers the lower opening by heat bonding or the like.

The electrode plate group 7 consisting of an anode plate, a cathode plate, a separator, etc. inserted into each battery chamber 6 is a positive electrode plate.

Both cathode plates have at least one connection tab 8a, 8b, 8C, and 8d on the top and bottom.

That is, in the one shown in FIG. 1, the anode plate has ears 8 a and 8 b at the upper left and lower right, and the cathode plate has ears 8 C and 8 d at the upper right and lower left, respectively.

In the anode plate of the electrode plate group 7, all of the same polarity plates and the upper left and lower right ears 8a and 8b are welded to each other to form connecting tabs 9a and 9b, and the partition wall is connected by the connecting piece. The connection of adjacent front cell cathode plates is integrated through the connection tray.

On the other hand, similarly for the cathode plate, the ears 8C and 8d of the same polarity plates are welded to each other to form connection troughs 9C and 9d, and these connection pieces are used to connect rear cells adjacent to each other through the partition wall. The connection is integrated with the connection rack of the anode plate.

The type of connection between the electrode plate groups of each cell shown in Figure 1 is the so-called bulkhead penetration type, in which a connecting piece is passed through the bulkhead to connect the connecting bars, but the connection is made between the middle frame and the top cover. It is also possible to use a so-called bulkhead over type in which connecting pieces are arranged along the wall surface of the inner frame so that the connecting pieces pass through.

In either connection type, the plate group is fixed to the partition wall of the battery compartment, so there is no need for a cracker to support the plate group as in the past, and the shape of the battery case can be adjusted accordingly. It can be simplified and assembled as a storage battery efficiently.

However, although this simplification of the shape of the battery case and the efficiency of battery assembly can be achieved, as mentioned above, both the positive and negative electrode plates have connectors at the bottom of the electrode plate group, and the distance from the bottom cover is close, so it is possible to prevent the battery from falling off. As the deposition of the substance progresses, there is a problem in that the deposited active material tends to cause a short circuit between the lower connecting bodies.

Therefore, in the present invention, the lower connecting body 9 of the positive and negative polar plates is
A partition piece 10 for partitioning between B and 9D and preventing a short circuit between the connected bodies due to accumulation of fallen active material is integrally attached to the partition wall 2 of the lower opening of the middle frame 3 and protrudes perpendicularly thereto to form the battery chamber. 6, and a fixing rib 11 corresponding to the partition piece 10 is also provided on the lower lid 5.

This divider piece 10 must be wide enough to prevent accumulated fallen active material from straddling and contacting the lower connector portion during normal battery service life, thereby preventing it from causing a short circuit. Through various studies, the inventors of the present invention have found that if this width is at most 50 mm, usually 4 Q mm, it is possible to effectively suppress short circuits at the lower connector portion caused by the deposited active material until the end of the battery's life. .

Also, the wider the partition piece 10 is, the more the partition effect will be exhibited, but the actual depth of the middle frame 3 will be limited, so from this point of view as well, the width of the partition piece 10 is necessary. Depending on the situation, it is preferable to use one that is as narrow as possible.

The present inventors took these picture points into consideration and also took into consideration the reinforcing effect as a battery case, and set the width of the partition piece 100 to 5 Q mm or less.

The lower end of this partition piece 10 is connected to the middle frame 3 after inserting the electrode plate group 7 into each battery chamber 6 and passing the connecting piece through the connecting piece through hole 12 of the partition wall 2 to connect the electrode plate groups. In order to facilitate the work when thermally welding the inner frame 3 and the lower cover 5, the inner frame 3 is flush with the lower end of the inner frame 3 at the same height.

If the lower ends of the partition piece 10 and the middle frame 3 are made flush in this way,
These can be heated and melted simultaneously using a common heating device.

Also, the rib 11 corresponding to the partition piece 10 on the lower lid 5 side is also
Workability can be improved by melting at the same time as heating and melting.

Figure 1 shows how to connect the electrode plates inserted into the battery chamber and connect the middle frame 3.
An upper cover 4 is fixed to the upper part of the battery, and a lower cover 5 is fixed to the lower part by heat welding to form a lead-acid battery.

In addition, 13 is a liquid port plug leading to each battery compartment, 14 is a terminal, and 1
Reference numeral 5 denotes a rib that facilitates insertion of the electrode plate group into the battery chamber and applies group pressure to the electrode plate group.

A life cycle test by charging and discharging was compared between the lead-acid battery of the present invention constructed in this manner and the conventional lead-acid battery in which the cells were connected only at the top of the electrode plate group described above. Although no internal short circuit occurred even after the test, the conventional one developed an internal short circuit after 230 cycles, and the battery performance significantly deteriorated.

Furthermore, the lead-acid battery of the present invention was less prone to internal short circuits than the aforementioned battery in which the cells were connected above and below the electrode groups.

This is because the partition piece provided at the lower part of the inner frame of the battery case satisfactorily prevents the accumulated fallen active material from coming into contact with the lower connector parts of both the positive and negative electrodes during the life of the battery.

Furthermore, in the lead-acid battery of this invention, the inner frame is reinforced by the partition piece provided on the inner frame, further increasing the strength of the battery case and preventing it from easily deforming due to lateral pressure or impact. This is also effective for protecting the welded and fixed parts.

Furthermore, since the battery case of the present invention does not require a cracker to support the electrode frame group, the unnecessary space below the electrode plate group can be minimized, and when electrode plates of a specified size are used, the unnecessary space can be reduced as much as possible. It is also possible to reduce the height of the battery and make it more compact.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of a lead-acid battery according to an embodiment of the present invention, Fig. 2 is an exploded cross-sectional view showing the battery case of the same lead-acid battery from the front, and Fig. 3 is an exploded cross-sectional view showing the case from the side. It is a diagram. 1...Battery case, 2...Bulkhead, 3...
...Middle frame, 4...Top lid, 5...Bottom lid,
6... Battery compartment, 7... Electrode plate group, 8a,
8b, 8C, 8d...Connection ear, 9a, 9
b, 9 C, 9d...connect, 10...
...Partition piece, 11...Fixing rib.

Claims (1)

[Scope of utility model registration request] A battery case is constructed by an inner frame that is open at the top and bottom and partitioned into a plurality of battery chambers by partition walls, and an upper and lower cover that covers the upper and lower openings of this inner frame, and a battery case that is inserted into each of the battery chambers. Connectors for positive and negative electrodes are provided on both the upper and lower parts of the plate group, respectively.
This connecting body is connected to the corresponding different polarity connecting body of the electrode plate group of the adjacent cell via the partition wall, and is formed to protrude perpendicularly to the lower part of the partition wall of the middle frame and to be located between the lower connecting bodies. A lead-acid battery consisting of a partition piece with a width of 50 mm or less that is integrally fixed to the lower cover.