JPH0145707B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a lead-acid battery using a plate grid made of a so-called antimony-free lead alloy that does not substantially contain antimony or a so-called low-antimony lead alloy that has an antimony content of less than 3%. It is about improvement.

Although this type of storage battery has little self-discharge, as it is repeatedly charged, the anode plate in particular stretches mainly in the vertical direction, which causes the anode strap to warp upward as shown by arrow A in Figure 9, and as a result, the anode plate The top end touches the bottom of the cathode strap, causing a short circuit.
Another drawback is that the sponge lead of the cathode plate comes into contact with the elongated anode plate as described above, making it easy to short-circuit. In particular, this drawback tends to be exacerbated as the length of the strap increases.

The present invention provides a lead-acid battery that does not have the above drawbacks by interposing a columnar support between the anode strap and the lower surface of the lid.

Note that storage batteries have been proposed in the past in which the entire electrode plate group is firmly fixed in the battery case by pressing both ends or the center of both the anode strap and the cathode strap with a fixing piece provided on the back of the lid. This is different from the purpose of the present invention of preventing short circuits caused by elongation of the anode plate, and is intended to improve the vibration resistance of the storage battery. The present invention attempts to eliminate the above-mentioned drawbacks, which are particularly noticeable in maintenance-free lead-acid batteries, by supporting only the anode strap with a columnar support and setting the support position at a specific position, as described in detail below. That is.

The present invention will be explained below based on examples.

First, in FIGS. 1 to 3 showing one embodiment of the present invention, 1 is a storage battery of the present invention, 2 is a battery case, and each is made of a thermoplastic synthetic resin such as polypropylene.
3 is a lid, 4 is a columnar support provided on the lower surface of the lid, 5 is an electrode plate group consisting of an anode plate 7 and a cathode plate 8 stacked with a separator 6 in between, 9 is an anode strap, 10 is a cathode strap, 11 is the free end of the anode strap 9 that is not fixed to the inner wall of the battery case 2. Said cylindrical support 4 is the free end 1 of the anode strap 9.
The configuration before forming the cylindrical support 4 is as follows:
The free end 1 of the anode strap 9 is shown in FIG. 1a.
A cylindrical support piece 12 is installed from the fitting part 13 that is fitted in the vicinity of the battery case 1 by a normal fitting method, and whose upper end 12a reaches the upper end 2a of the battery case. It consists of a cylindrical support piece 4a that reaches up to the lower edge 3b. The support piece 4a and the support piece 12 are made of thermoplastic synthetic resin such as polypropylene. In the figure, T, 3T (meaning three times T) and L indicate the thickness, width and length of the anode strap 9, respectively, and l indicates the distance from the free end 11 of the anode strap 9 to the support piece 12. Indicates the distance to the center.

Next, to explain the procedure for assembling the storage battery shown in the figure, first, the electrode plate group 5 obtained by the conventional method is inserted into the battery case 2, each cell is connected, and then the lower end of the support piece 12 is placed at a predetermined position on the anode strap 9. After that, the battery case 2 and the lid 3 are joined by heat welding or the like, and at the same time, a fitting part 13 is fitted on the upper end of the support piece 12 and on the lower surface of the lid 3 corresponding to the support piece 12. The anode strap 9 is fixed by joining the lower end of the support piece 4a.

The storage battery 1 of the present invention uses columnar supports 4 and 12 interposed between the strap 9 and the lower surface of the lid 3 to prevent the upward warping of the anode strap 9 caused by the elongation of the anode plate 7 as described above. This prevents short circuits caused by the upper end of the anode plate 7 coming into contact with the lower surface of the cathode strap 10 or by the sponge lead of the cathode plate 8 coming into contact with the stretched anode plate 7. .

In addition to the structure shown in the above embodiment, the structure of the columnar support may be, for example, a columnar support piece 12' whose lower end is fitted onto the anode strap 9 as shown in FIG.
An anode strap 9 whose upper end fits into a recess 14 provided on the lower surface of the lid 3', or a columnar support piece 4' provided on the lower surface of the lid 3'' as shown in FIG.
It is possible to implement a device that is close to or in contact with the top surface of the device. When the support piece 4' is arranged close to the upper surface of the anode strap 9, no actual damage will occur if the gap between the two is within 3 mm.

Next, the position of the columnar support 4 will be explained.

Storage battery A using a plate grid made of an antimony-free lead alloy, battery B using a plate grid made of a low antimony lead alloy, and plate grid made of a lead alloy with an antimony content of 4 to 5%. Regarding the storage battery C using the above, the length L of the anode strap 9 and the upward curvature of the strap 9 after repeated charging and discharging tests (dimensions indicated by h in Fig. 6)
When the relationship between In this case, the thickness T and width 3T of each anode strap 9 were set to standard dimensions of 6 mm and 18 mm, respectively.

As is clear from FIG. 7, in general, the warp h of the anode strap 9 is relatively small in the storage battery C using a normal lead alloy, but in the storage battery A using an antimony-free lead alloy, the anode strap 9 When the length L became 30 mm or more, the warp h suddenly increased, and in the case of the storage battery B using a low antimony lead alloy, when the length L became about 40 mm or more, the warp h suddenly increased.

From the above experimental results, when the thickness and width of the anode strap 9 are set at a ratio of T:3T, that is, 1:3, the distance l from the free end 11 of the strap 9 to the center of the columnar support 4 is , respectively, for storage battery A within the equivalent of 30mm5T, and for storage battery B
So, if you place it within about 40mm and about 7T,
Even if the anode plate 7 stretches as use progresses, the anode strap 9 can be substantially prevented from bowing upward.

This was also confirmed through another experiment, the results of which are shown in FIG. In this experiment, the relationship between the distance l from the free end 11 of the anode strap 9 to the center of the columnar support 4 and the battery life (number of months of use) was investigated for the same storage batteries A and B as described above. . As is clear from the figure, in the storage battery A, the free end 1 of the anode strap 9
The distance l from 1 to the center of the columnar support 12 is 30 mm.
It can be seen that a remarkable effect is produced if the value of l is within approximately 40 mm, and in the case of storage battery B, a remarkable effect is produced if the value of 1 is within approximately 40 mm.

According to the present invention, as described above, the anode strap has a simple structure in which only a support piece is interposed between the anode strap and the lower surface of the lid, and the electrode plate grid body made of antimony-free or low-antimony lead alloy is used. It is possible to prevent short circuits caused by elongation of the anode plate of the storage battery, and as a result, a storage battery with a long life can be obtained, making it ideal for so-called maintenance-free lead-acid batteries.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional side view of the essential parts showing an embodiment of the storage battery of the present invention, FIG. 1a is a longitudinal sectional side view of the essential parts immediately before the battery case and the lid are joined together, FIG.
Figure 3 is a sectional view taken along line A-A in Figure 1, Figures 4 and 5.
Fig. 6 is a longitudinal sectional side view of the main part showing another embodiment of the storage battery of the present invention, Fig. 6 is a side view of the main part showing the state in which the anode strap is warped upward, and Fig. 7 shows the length of the anode strap and the warpage of the strap. Figure 8 is a graph showing the relationship between the distance l from the free end of the anode strap to the center of the columnar support and the battery life. FIG. 2 is a longitudinal sectional side view of main parts of a conventional storage battery shown in FIG. 1: storage battery of the present invention, 3: lid, 4: columnar support,
4a/12: Support piece, 9: Anode strap, 1
1: free end, 14: recess, T: thickness of anode strap, 3T: width of anode strap, l:
Distance from the free end of the anode strap to the center of the support piece.

Claims (1)

[Claims] 1. In a lead-acid battery 1 using a plate grid made of a lead alloy that does not substantially contain antimony or a lead alloy with low antimony, a columnar support 4 is provided only between the anode strap 9 and the lower lid surface 3a. A lead-acid battery characterized by interposing. 2. The columnar support 4 is assembled by joining the upper end 12a of the columnar support piece 12 whose lower end is fitted to the anode strap 9 and the lower end of the columnar support piece 4a provided on the lower lid surface 3a corresponding to the columnar support piece 12. A lead-acid battery according to claim 1, which is formed by forming a lead-acid battery according to claim 1. 3. The lead-acid battery according to claim 1, wherein the upper end of the columnar support piece 12' whose lower end is fitted onto the anode strap 9 is fitted into the recess 14 provided on the lower surface of the lid. 4. The lead-acid battery according to claim 1, wherein the lower end of the columnar support piece 4' provided on the lower surface of the lid is close to or in contact with the upper surface of the anode strap 9. 5 In a lead-acid battery 1 using an electrode grid made of a lead alloy that does not substantially contain antimony, the thickness and width of the anode strap 9 are T.
and 3T, the distance l from the free end 11 of the strap to the center of the columnar support piece 12 is 5
The lead-acid battery according to any one of claims 1 to 4, wherein the columnar support piece 12 is disposed at a position that is equal to or less than T. 6 When the thickness and width of the anode strap 9 are T and 3T, respectively, in the lead-acid battery 1 using a plate grid made of a low-antimony lead alloy, the distance from the free end 11 of the strap to the center of the columnar support piece 12 The lead-acid battery according to any one of claims 1 to 4, wherein the columnar support piece 12 is arranged at a position where the distance l to the columnar support piece 12 is 7T or less.