JPH06223867A - Lead-acid battery - Google Patents

Abstract

PURPOSE:To prevent the generation of short circuit at a lower part, and prolong a lifetime by providing a plate group support mode of a substance, which can be dissolved by sulfuric acid, in the bottom part of a battery jar. CONSTITUTION:Plate group supports 8 are provided as a substitute for negative plate supporting saddles 2, and the supports 8 are made of the material, which is soluble in the sulfuric acid and which is harmless to a lead-acid battery. Water glass as a binder is added to the powder type sodium sulfate, and they are kneaded to form the paste, and this paste is formed into an appropriate largeness and dried to manufacture a support 8. A difference of the life factor of the positive electrode grid alloy is caused by the difference of the deformation quantity of a positive plate due to the difference of the grid strength, and the deformation of a positive plate made of zinc - antimony alloy is small. Since the support 8 is not dissolved in the sulfuric acid, fell grains of the active material are not stored in a separator 4 between the leg of the negative plate 3 and the lower part of the positive plate like a case where the saddle 2 for supporting the negative plate is provided, and the generation of short circuit at the lower part is prevented. Furthermore, besides sodium sulfate is harmless, the sodium sulfate prevents the rise of the solubility of lead when a specific gravity of the electrolyte is lowered, and the generation of short circuit is prevented effectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in lead acid batteries.

[0002]

2. Description of the Related Art Lead acid batteries are currently used for automobiles,
Although it is widely used in all fields including industrial applications, automobile batteries are in great demand, and are required to be lightweight, cost-saving, maintenance-free, long life, and stable quality.

FIG. 2 shows a lead storage battery generally used for automobiles and the like. The battery case 1 is provided with flat portions 2, 3'having a thickness of 1 to 3 mm and a height of about 10 mm, which are integrated with the bottom of the battery case and the partition walls. Electrode plate group 9 with separator 4 superposed
Is placed on the club at the foot 10 part of the plate. 3 is a negative electrode plate, 5 is an electrode plate ear, 6 is a strap, and 7 is a terminal.

[0004] In addition to preventing the positive and negative electrode plates and the separators that form the electrode plate group from shifting when inserting the electrode plate group into the battery case and determining the position of the terminal 7, the charging and discharging mechanism. Particles of the active material that have fallen off from the electrode plate due to repeated vibrations and vehicle vibrations are deposited in the space between the cracks to prevent contact between the lower part of the electrode plate group and the active material particles, It has the function of making short circuits less likely to occur.

However, even if the clutch is provided, many lower short circuits occur. This is because the particles of the active material that have fallen off fly up due to convection of the electrolytic solution, etc., and are stacked on the separator between the legs of the negative electrode plate and the lower part of the positive electrode plate and the separator on the negative electrode plate supporting member 2 ′. The cause is that it accumulates in the mat portion, is reduced and grows as metallic lead, and contacts the lower lattice portion of the positive electrode plate.

Therefore, it has been desired to develop a method for preventing a lower short circuit without impairing the function of the clutch.

[0007]

DISCLOSURE OF THE INVENTION The present invention eliminates the above-mentioned drawbacks and is characterized in that an electrode plate group support made of a substance soluble in sulfuric acid is provided in place of the conventional battery cell clutter. It is a lead-acid battery and is intended to prevent a lower short circuit.

[0008]

EXAMPLE A group of electrode plates of a lead acid battery for automobile (nominal capacity of 28 Ah, 5 hour rate) having four positive electrode plates and five negative electrode plates per cell were laminated and arranged according to a conventional method. Generally, there are two types of alloys for the positive electrode plate grid, a lead-calcium alloy and a lead-antimony alloy. Here, for both alloys, those having the composition used in a normal lead-acid battery are used. Two kinds of electrode plate groups were manufactured using a positive electrode plate using a lead-calcium alloy in a positive electrode plate grid and a positive electrode plate using a lead-antimony alloy in a positive electrode plate grid.

FIG. 1 is a schematic sectional view showing an embodiment of the lead acid battery of the present invention. In the figure, 1 is a battery case, 2 is a positive electrode plate supporting member, 3 is a negative electrode plate, 4 is a separator, 5 is an electrode plate ear,
6 is a strap. Reference numeral 7 is a terminal, and 8 is an electrode plate group support provided in place of the negative electrode plate supporting member. Reference numeral 9 is an electrode group, and 10 is a foot of the electrode plate.

The electrode plate group support 8 must be made of a material that is soluble in sulfuric acid and is not harmful to lead acid batteries. This time, water glass was added as a binder to powdery sodium sulfate, and the mixture was plastered to form a paste, which was then molded into an appropriate size and dried to prepare an electrode plate assembly support. Table 1 shows the contents of the test battery.

[0011]

[Table 1]

These batteries were subjected to liquid injection and battery case formation by ordinary methods, and then their life performance was evaluated by a JIS D5301 heavy load life test. Discharge current is 20A,
The charging current is 5 A and the test temperature is 42.5 ± 2.5 ° C. The results are shown in Table 2.

[0013]

[Table 2]

The conventional battery (No. 3) using a lead-calcium alloy for the positive electrode grid has a life of 50 cycles. On the other hand, the battery of the present invention (No. 1) using a soluble electrode plate group support in place of the club had a life cycle performance of 150 cycles, which is three times longer.

Similarly, even in the battery using the lead-antimony alloy for the positive electrode grid, the conventional product (No. 4) had 250 cycles, whereas the product of the present invention (No. 2) had a significant 400 cycles. Improved life performance.

Next, these batteries were disassembled and investigated. In the conventional products (Nos. 3 and 4), a short circuit occurred between the legs of the negative electrode plate and the lower part of the positive electrode plate, which was the cause of the life. The difference in the number of lifespan due to the positive electrode grid alloy is due to the difference in the amount of deformation of the positive electrode plate due to the difference in the grid strength. In the lead-calcium alloy, compared to the lead-antimony alloy,
The deformation of the positive electrode plate was very large.

On the other hand, in the batteries (Nos. 1 and 2) of the present invention, the electrode plate group support was dissolved and disappeared. Therefore, the particles of the active material that had fallen off did not accumulate in the separator portion between the legs of the negative electrode plate and the lower portion of the positive electrode plate, and short circuits did not occur.

Further, sodium sulfate dissolved in sulfuric acid is not only harmless to the lead storage battery, but also effective in preventing the increase in the solubility of lead when the specific gravity of the electrolytic solution is lowered, and is therefore effective in preventing a short circuit. It is a thing. Although sodium sulfate was used this time, the present invention is not limited to this, and any material containing an alkali metal ion or an alkaline earth metal ion may be used, and the same effect can be expected with magnesium sulfate, potassium sulfate, or the like.

[0019]

As is apparent from the above-described embodiments, the present invention prevents the lower short circuit by providing an electrode plate group support made of a substance soluble in sulfuric acid instead of the conventional battery container. To provide a long-life lead-acid battery that can be prevented
Its industrial value is enormous.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of the lead acid battery of the present invention.

FIG. 2 is a diagram showing an example of a conventional lead storage battery.

[Explanation of symbols]

 1 Battery case 2 Cura (for supporting positive electrode plate) 3 Negative electrode plate 4 Separator 8 Electrode plate group support 9 Electrode plate group 10 Feet of electrode plate

Claims (2)

[Claims] 1. A lead storage battery comprising an electrode plate group support made of a substance soluble in sulfuric acid at the bottom of the battery case. 2. The lead acid battery according to claim 1, wherein the electrode plate group support contains an alkali metal salt or an alkaline earth metal salt as a main component.