JPH069144B2 - Sealed lead acid battery - Google Patents

Description

TECHNICAL FIELD The present invention relates to a sealed lead acid battery in which the amount of electrolytic solution is limited and the negative electrode absorbs oxygen gas generated from the positive electrode during charging.

[Problems to be solved by the conventional technology / invention] The sealed lead-acid battery has a function of absorbing oxygen gas generated from the positive electrode at the time of charging at the negative electrode, does not discharge gas to the outside of the battery, and is in use, It is a completely sealed battery manufactured with features such as no leakage of electrolyte. The basic configuration of this battery is the same as that of the liquid lead-acid battery, but is greatly different in that the electrolytic solution is specially devised to impart the above-mentioned characteristics. That is, in order to prevent the leakage of the electrolytic solution from the battery, the amount of the electrolytic solution to be used is limited, the electrode plate group is impregnated and held, and an excessive amount that freely moves in the battery case does not exist (hereinafter, the retainer). Method) or a method of using an electrolytic solution in which an inorganic oxide is mixed in the electrolytic solution to make it in a non-fluid state (hereinafter referred to as a gel method) to hold the electrolytic solution.

By the way, the sealed lead-acid battery absorbs the oxygen gas generated during charging inside the battery to prevent the decrease of the electrolyte during charging like the liquid type lead-acid battery and save the maintenance work such as rehydration during use. It is a battery designed for Therefore, if the absorption of oxygen gas is poor, the electrolytic solution may decrease, which may eventually lead to a decrease in the capacity and life of the storage battery, and it is extremely difficult to prevent leakage of the electrolytic solution and enhance the oxygen gas absorption capacity. It's important. In order to efficiently absorb the oxygen gas generated in the battery, it is desirable that the oxygen gas generated in the positive electrode easily reach the negative electrode and that the negative electrode has a large number of portions involved in the reaction with oxygen. However, when a gel-type electrolyte is used, the gel-like electrolyte is filled between the positive electrode and the negative electrode, which prevents movement of oxygen gas, and the negative electrode is almost covered with the gel-type electrolyte. The area involved in absorption of oxygen gas is reduced, and oxygen gas is not absorbed much and is easily discharged to the outside of the battery. On the other hand, the retainer method is one in which the electrolytic solution is contained in the separator, and in this case, by regulating the amount of the electrolytic solution, it is possible to secure pores that become passages for oxygen gas in the separator, Oxygen gas can be absorbed efficiently. Therefore, in order to realize a sealed lead acid battery having an excellent oxygen gas absorption capability, it is judged that the method of holding the electrolytic solution by the retainer method is effective. However, since this method holds the electrolytic solution in the pores in the separator by the capillary phenomenon, when the electrode plate is used in the vertical direction, the height of the electrode plate that can hold the electrolytic solution of uniform concentration Will be restricted. Figure 2 shows the results of the alternating charge and discharge test of a sealed lead acid battery with a plate height of 40 cm made by the retainer method. By alternately charging and discharging, the amount of electricity that could be taken out gradually decreased. Regarding the discharge characteristics, comparing the data of the initial stage and the latter half of the test, as shown in FIG.
The larger the number of discharges, the smaller the voltage drop at the start of discharge and the shorter the discharge duration. The cause of this is that the concentration of the electrolytic solution impregnated in the separator becomes uneven,
It is thought that this is because there is an electrolyte solution having a high specific gravity at the bottom of the electrode plate and a low specific gravity at the top. The electrode plate with the low specific gravity electrolyte solution does not contribute to the charge / discharge reaction, and the charging / discharging occurs exclusively in the lower part of the electrode plate with the high specific gravity electrolyte solution. That is, in terms of battery performance, it is equivalent to a battery using a small electrode plate and a high specific gravity electrolyte solution, and the electromotive force of the battery increases as the specific gravity increases, but the amount of electricity that can be taken out decreases as the electrode plate decreases. Can be interpreted as

When the sealed lead-acid battery is configured by the retainer method as described above, a battery having excellent oxygen gas absorption performance can be manufactured, but there is a limit to the height at which the electrolyte solution having a uniform concentration can be held, There is a drawback that it is difficult to manufacture a sealed battery having a large capacity.

[Means for Solving the Problems] The present invention eliminates the non-uniform concentration of the electrolyte solution impregnated in the separator in the sealed lead-acid battery using the retainer system as described above, and has an excellent oxygen gas absorption capacity. It is intended to provide a sealed lead acid battery that is reliable from the viewpoint of performance, and for that purpose, the present invention is configured so that the electrode plate group of the sealed lead acid battery by the retainer method is horizontal to the installation surface of the battery, and A partition plate that does not allow liquid to permeate is inserted in each of the plate groups.

[Examples] Examples of the sealed lead-acid battery of the present invention will be described below.

FIG. 1 shows an embodiment of the sealed lead acid battery of the present invention, in which 1 is a positive electrode, 2 is a negative electrode, 3 is a separator, 4 is a battery case, 5 is a negative pole, 6 is a positive pole, and 7 is a partition plate. As is clear from FIG. 1, in this embodiment, the positive electrode 1, the negative electrode 2, and the separator 3 constituting the electrode plate group are alternately stacked in the horizontal direction with respect to the bottom surface of the battery, and are divided into the electrode plate group. The plate 7 is inserted. Since the partition plate 7 prevents the movement of the electrolytic solution above and below the electrode plate group, it is made of a material that does not permeate the electrolytic solution. Further, when the number of electrode plates forming the electrode plate group is large, a plurality of partition plates 7 may be inserted at regular intervals. Further, as shown in FIG. 1, it is desirable that the negative electrode 2 be in contact with both surfaces of the partition plate 7 so that a plurality of unit cells are laminated.

In a conventional sealed lead-acid battery, the separator is vertical to the bottom surface (installation surface) of the battery, so gravity acts on the electrolytic solution inside the separator and the height of the separator is such that it can hold a uniform concentration of electrolytic solution. Limitation occurs, the height of the electrode plate also becomes limited, or even if it is possible to barely hold a uniform electrolytic solution, concentration distribution easily occurs by repeating charging and discharging several times, and it becomes less than the designed capacity. There was a problem. These are all due to the electrolyte contained within the vertical separator. Further, in order to improve the concentration distribution of the electrolytic solution, it has been proposed to arrange the electrode plate in the horizontal direction (for example, JP-A-54-134336 and JP-A-58-206074).

By taking such measures, the height of the electrode can be suppressed, so that non-uniformity of the electrolyte concentration and amount can be considerably suppressed in normal use where the number of discharges is small. However, when the number of discharges becomes frequent, gas is generated on the surface of the electrode plate due to overcharging in the latter half of charging, and as a result, the phenomenon in which the electrolytic solution impregnated in the glass mat separator is extruded occurs. Experiments have shown that such measures alone are still insufficient. However, in the embodiment of the present invention, the electrode plate group is assembled horizontally with respect to the bottom surface (installation surface) of the battery, and the partition plate is inserted for every several electrode plates in the electrode plate group. Even if you make a battery according to
Since the electrolytic solution is impregnated in the horizontal separator 3, it is difficult for the electrolytic solution concentration to become non-uniform due to the action of gravity. In addition, even if a plurality of electrode plates are stacked horizontally to obtain a large capacity and a storage battery having a height such that the concentration of the electrolyte solution is nonuniform in the upper and lower parts of the electrode plate group is used in the present invention, Since the partition plate 7 is inserted for every several electrode plates in the plate group, the electrolytic solution on the upper part of the electrode plate group does not move to the lower part of the electrode plate group by the action of gravity. It is also possible to prevent non-uniformity of the concentration. Therefore, in the present invention,
The problem that the size of the electrode plate to be used is limited, and the concentration distribution of the electrolytic solution occurs due to repeated charging / discharging, resulting in a decrease in battery capacity, is completely eliminated.

FIG. 4 shows the result of the charge / discharge test of the embodiment of the present invention having the above-mentioned structure. In the example of the present invention used for the test, the electrode plate having a height of 40 cm is used, but even if charging and discharging are performed alternately,
No decrease in capacity was observed, but rather the capacity that could be taken out increased with the number of charge and discharge cycles. That is, in the sealed lead-acid battery according to the present invention, it is understood that the uneven distribution phenomenon of the electrolytic solution, which occurs in the battery in which the electrode plate group is vertically assembled unlike the conventional product, does not occur at all. Further, in the present invention, in addition to arranging the electrode plates in the horizontal direction, a partition plate that does not allow the electrolyte to permeate is arranged for every several electrode plates, so that good results can be obtained under all use conditions. Therefore, a significant effect can be obtained as compared with the case of only the horizontal arrangement. Further, in the method of constructing the battery according to the present invention, there is no limitation on the size of the separator and the electrode plate used, and it is particularly effective when producing a sealed lead-acid battery having a large capacity, and moreover, absorption of oxygen. It is possible to manufacture a battery having a characteristic of a retainer type electrolytic solution that is excellent in capacity.

[Effects of the Invention] As described above, in the sealed lead acid battery of the present invention, the electrode plate group is stacked horizontally with respect to the battery installation surface, and the partition plate is inserted into the electrode plate group so that the electrolytic solution is horizontally fed. Since it is impregnated and held in the separator, the electrolytic solution descends due to the effect of gravity, and the concentration distribution of the electrolytic solution occurs in the separator, and the electrolytic solution distribution in the upper and lower electrode plate groups There is no problem such as non-uniformity, that is, there is no limitation on the size of the separator or the electrode plate to be used, and therefore, there is an advantage that it can be applied to a particularly large capacity.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing an embodiment of the sealed lead acid battery of the present invention, FIG. 2 is a characteristic diagram showing the discharge capacity of a sealed lead acid battery of the conventional system, and FIG. FIG. 4 is a characteristic diagram showing the discharge capacity of the lead-acid battery, and FIG. 4 is a characteristic diagram showing the discharge capacity of the sealed lead-acid battery of the present invention. 1 ... Positive electrode, 2 ... Negative electrode, 3 ... Separator, 4 ... Battery case, 5 ...
Negative pole, 6 ... Positive pole, 7 ... Partition plate

Claims (1)

[Claims] 1. A positive electrode, a negative electrode, a separator and the electrode,
In a sealed lead-acid battery composed of a prescribed amount of electrolytic solution held by a separator and absorbing oxygen gas generated from the positive electrode at the time of charging, the positive electrode group, the negative electrode, and the separator are alternately stacked. A laminated sealed lead-acid battery, characterized in that the battery is assembled so as to be horizontal to the installation surface of the battery, and a partition plate that does not allow liquid to pass through is inserted in each of the electrode plates.