JPH11339843A - Sealed lead-acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the utilization factor of a positive electrode active material when a paste positive electrode having a thickness within a specific range is used by holding a specific % of the injected electrolyte weight with the paste positive electrode, holding the specific % of the injected electrolyte weight with a paste negative electrode, and setting a porosity of the active material layer of the paste positive electrode to a specific %. SOLUTION: The injected electrolyte weight of 16.5-24.0 wt.% is held by a paste positive electrode having the thickness of 4.0 mm or above, and 10.5-18.0 wt.% of the injected electrolyte weight is held by a paste negative electrode. The porosity of the active material layer of the paste positive electrode is set to 58-60%. The moisture content of a paste active material is changed to change the porosity of the positive electrode, and the porosity of the chemically formed active material is made 55, 58, 60, 61% respectively. A chemically unformed positive electrode is obtained after aging and drying. A high-capacity battery can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a paste type positive electrode plate,
The present invention relates to increasing the capacity of a long-life type sealed lead-acid battery using a paste-type negative electrode plate and a retainer.

[0002]

2. Description of the Related Art In recent years, there has been an extremely strong demand for extending the life of sealed lead-acid batteries. The life of the sealed lead-acid battery has been improved to the same level as the life of machines and equipment using the battery by various improvements. In addition, as the positive electrode plate and the negative electrode plate used in the sealed lead-acid battery, a paste-type electrode plate is generally used, which is manufactured by filling a grid-like body of a lead alloy with a paste-like active material. A large number of these paste-type electrode plates are laminated via a retainer to produce an electrode group, which is assembled in a battery case, and then formed into a battery case to manufacture a sealed lead-acid battery.

In these long-life sealed lead-acid batteries, a high capacity has recently been strongly demanded. In a long-life sealed lead-acid battery, the discharge capacity strongly depends on the diffusion of sulfate ions in the electrolyte.
A long-life sealed lead-acid battery has four positive plates.
mm or more, the sulfate ions hardly diffuse into the inside of the electrode plate, and there is a problem that the utilization rate of the active material is low. Therefore, as means for increasing the capacity of a long-life sealed lead-acid battery, studies have been made on making the active material layer porous, making the electrode plate thinner, and using an electrolyte having a high specific gravity. However, when these methods are used, there is a problem that the life of the sealed lead-acid battery is shortened.

On the other hand, attempts have been made to increase the thickness of a retainer, which is an electrolyte holder, to hold more electrolyte and supply a large amount of sulfate ions to the electrode. However, when this method is used, the distance between the positive electrode plate and the negative electrode plate becomes longer, so that the internal resistance increases. As a result, there is a disadvantage that the discharge voltage of the battery decreases.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to improve the utilization rate of a positive electrode active material in a long life type sealed lead-acid battery using a paste type electrode plate having a positive electrode plate having a thickness of 4 mm or more. It is.

[0006]

Means for Solving the Problems In order to solve the above problems, in the first invention, in a sealed lead-acid battery using a paste-type positive electrode plate having a thickness of 4.0 mm or more, the weight of the injected electrolyte is reduced. 16.5 to 24.0 wt. % Was held on the paste-type positive electrode plate, and 10.5% of the weight of the injected electrolyte solution.
~ 18.0 wt. % Of the active material layer of the paste-type positive electrode plate is 58 to 60%.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Positive Electrode As the positive electrode lattice, two types of lattices of W140 × L240 × T4.2 (mm) or W140 × L240 × T5.5 (mm) made of a lead-calcium-tin alloy were prepared. Next, about 25 wt. % Lead powder, diluted sulfuric acid, and water are kneaded to prepare a paste-like active material. The above-mentioned grid body having a thickness of 4.2 mm (T4.2 mm) was coated with a paste-like active material having a weight of 460 g after the formation of the active material, and 5.5 mm in thickness.
Each of the lattice bodies (T5.5 mm) was filled with a paste-like active material having a weight of 600 g of the active material after chemical formation, and was aged and dried by a conventionally used method to obtain an unformed positive electrode plate. In addition, in order to change the porosity of the positive electrode plate, the amount of water in the paste-like active material was changed so that the porosity of the active material after chemical formation was 55, 58, 60, and 61%, respectively. Then, an unformed positive electrode plate was obtained after aging and drying by a conventionally used method.

[0008] 2. Negative electrode As a negative electrode grid, W140 × L240 × T2.6, W140 × L240 × T2.4 (mm), W140 × made of lead-calcium-tin alloy
Three types of lattices of L240 × T1.8 (mm) or W140 × L240 × T1.5 (mm) were prepared. Approximately 2 of lead metal mainly composed of lead monoxide
5 wt. % Of lead powder, barium sulfate, sulfuric acid, lignin and freon-based surfactant are kneaded with water to prepare a paste-like active material. The above-mentioned 2.4 mm-thick lattice (T2.4 mm) is a paste-like active material having a weight of 280 g of active material after formation, and a 1.8 mm-thick lattice (T1.8 mm).
The paste of the paste-like active material having a weight of 210 g of the active material after formation is applied to the lattice of No. 1, and the paste of the active material after formation is 180 g in weight of the lattice of a 1.5 mm-thick lattice (T1.5 mm). Each of the strike-shaped active materials was filled, and aged and dried by a conventionally used method to obtain an unformed negative electrode plate.

3. Fabrication and test of sealed lead battery Four of these fabricated positive electrode plates and five negative electrode plates were laminated via a retainer made of a nonwoven fabric made of glass fiber to form an electrode group, which was inserted into a battery case and joined. Insert a spacer made of polypropylene so that the pressure becomes 20 kgf / dm ² and
V, 100 Ah sealed lead-acid battery was produced. And
A diluted sulfuric acid electrolyte was injected, and the liberated electrolyte was discharged to obtain a sealed lead-acid battery. Then, battery formation was performed with an overcharge amount of 230%, and the specific gravity of the electrolytic solution after the battery formation was adjusted to 1.26. The battery after battery case formation should be stored in an ambient temperature of 25 ± 2 ° C.
Discharge was performed at a time rate (1 CA), the discharge capacity was measured, and the utilization rate of the positive electrode active material was calculated from the filling amount of the positive electrode active material and the discharge capacity. In addition, the amount of the electrolyte in the positive electrode plate, the amount of the electrolyte in the negative electrode plate, and the porosity of the positive electrode active material layer were measured by disassembling the battery that was subjected to the charge / discharge test.

[0010]

EXAMPLES (Examples 1 and 2 and Comparative Examples 1 and 2) A sealed lead-acid battery having the specifications shown in Table 1 was manufactured under the above conditions, and the amount of the electrolyte in the positive electrode, the weight of the electrolyte in the negative electrode, and the weight of the positive electrode were measured. The utilization rate of the active material was measured. As shown in Table 1, 16.5 to 24.0 wt. % Is held in the paste-type positive electrode plate, the utilization rate of the positive electrode active material is high.

[0011]

[Table 1]

Examples 1 and 2 and Comparative Examples 3 and 4 A sealed lead-acid battery having the specifications shown in Table 2 was prepared under the conditions described above, and the amount of the electrolyte in the positive electrode, the weight of the electrolyte in the negative electrode, and the activity of the positive electrode were measured. Material utilization was measured. As shown in Table 2, 10.5 to 18.0 wt. % Is held in the paste type negative electrode plate, the utilization rate of the positive electrode active material is high.

[0013]

[Table 2]

Examples 3 to 6 Under the above conditions, sealed lead-acid batteries having the specifications shown in Table 3 were prepared, and the porosity of the positive electrode and the utilization rate of the positive electrode active material were measured. As shown in Table 3, the utilization rate of the positive electrode active material is high when the porosity of the positive electrode active material layer is in the range of 58 to 60%.

[0015]

[Table 3]

[0016]

As described above, according to the present invention, the thickness is 4.
In a sealed lead-acid battery using a positive electrode plate of 0 mm or more,
When the amount of electrolyte in the positive electrode is 16.5 to 24.0 wt. %, The amount of the electrolyte in the negative electrode is in the range of 10.5 to 18.0%. In this state, the porosity of the positive electrode active material is 58%
When the content is set to 60%, the utilization rate of the positive electrode active material can be increased, so that the capacity of the battery can be increased.

Claims (2)

[Claims] In a sealed lead-acid battery using a paste-type negative electrode plate and a paste-type positive electrode plate having a thickness of 4.0 mm or more, 16.5 to 24.0 wt. %
Was held on the paste-type positive electrode plate, and 10.5 to 18.0 wt. % In the paste-type negative electrode plate. 2. The sealed lead-acid battery according to claim 1, wherein the porosity of the active material layer of the paste-type positive electrode plate is 58 to 60%.