JPH0652654B2 - Lead acid battery electrode plate manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improvement of a paste type anode plate.

2. Description of the Related Art A conventional paste-type lead-acid battery electrode plate has a grid body filled with a paste containing lead oxide diluted hydrochloric acid and water. The porosity of the active material and the particle size of the lead powder were set such that the paste type electrode plate, particularly the anode plate, had a life of about 40 to 50 ° C. so that various performances were sufficiently exhibited.

Problems to be Solved by the Invention However, in recent years, 113SL has been adopted for automobiles and the like.
In the lead acid battery for I, due to an increase in the mounting density of parts due to the vehicle design and electronic control system, the surrounding environment has been changed such that the battery itself is exposed to high temperature. Therefore, it is required to improve the durability of the lead acid battery for SLI, and the need for maintenance during use is high.

At high temperatures, the anode plate of a lead-acid battery easily corrodes the lattice and deteriorates the durability of lead dioxide, which is the active material.Therefore, to improve the durability of the active material, mix lead oxide with water and dilute sulfuric acid. It is desirable to apply a so-called hard paste having a small ratio and a large paste density to the grid body. However, in order to uniformly fill the grid with the hard paste, it is necessary to increase the strength of the grid more than necessary, and for that purpose, it is necessary to increase the weight of the grid, which is not economical. Therefore, it is necessary to obtain a paste having a good filling property even in a high paste density state in order to improve the durability of the lead storage battery at high temperatures.

Means for Solving the Problems In the present invention, in view of the above points, various studies have been made to appropriately improve the life of the anode plate at a high temperature, and when the lead powder is kneaded with diluted sulfuric acid, the soluble silica is 10 to 10%. Lead powder in a pre-kneaded state having free water mixed by using an aqueous solution containing 80 mg / [lead powder in a state after the step of kneading before adding dilute sulfuric acid (hereinafter referred to as "lead in a pre-kneaded state" Powder))], and a paste having a good filling property is obtained even at a high paste density. Further, the need for maintenance at high temperatures is due to the antimony content in the anode grid alloy being suppressed to 2% or less.

The paste obtained by the present invention is in the region of a very high paste density in the past, but as a function of good filling property,
Since the aqueous solution of soluble silica is mixed with dilute sulfuric acid in a free state, the soluble silica content is chemically adsorbed on the surface of tribasic lead sulfate or lead sulfate produced by the reaction of dilute sulfuric acid and lead powder. It is considered that the slipperiness between the paste particles was increased and the filling property in the lattice was improved even at a high paste density. Further, if the soluble silica content is within the range of the present invention, since it is harmless to the electromotive reaction of the lead storage battery, it is possible to improve the durability of the anode plate without affecting the performance after the initial charging. It is thought that it has become.

Action A paste with good filling properties can be obtained even with a high paste density.

Example As an anode grid alloy, 1.5% Sb, 0.1% Sn, 0.25%
As, 0.005% S, width 141 mm, and 11 high, consisting of balance lead
0mm, thickness 1.6m, weight 55g / sheet cast grid, cathode grid alloy 0.12% Ca, 0.3% Sn, 0.02% Al,
Using a cast grid body having the same size and a thickness of 1.3 mm and made of the balance lead, a 5 HR capacity 48 Ah test battery was prototyped using the following paste.

For comparison, a battery A obtained by filling an anode paste (density 3.8 to 3.9, water content 14%) kneaded without using an aqueous solution of soluble silica has a soluble silica content of 1 at the time of kneading. Batteries B, C, D, E, obtained by kneading the paste with an aqueous solution of 10, 20, 40, 80, 150 mg /
F and G were tested at the same time. In the test, constant voltage overcharge of 2.4V per cell was performed at 80 ℃, and 300V every 50h.
A discharge capacity test was performed.

At that time, the change in discharge capacity is shown in the drawing. as a result,
Battery A using the conventional paste, about 7 times (350H)
It became 50%, and Battery G reached the end of life after 6 times (300 hours). Batteries C, D, E, and F have a longer life than conventional battery A. In particular, it was found that a paste using an aqueous solution containing 10 to 80 mg / soluble silica has a long life. The difference in effect depending on the content of soluble silica was considered to be related to tribasic lead sulfate produced by the reaction between the amount of dilute sulfuric acid used during kneading and lead oxide, and the amount of lead sulfate produced, With the anode paste containing 15% lead sulfate, no particular change in the effect was observed, so it is considered that this is related to the change in free water, which is not involved in kneading. It is not clear whether this water content depends on the water quality of the soluble silica aqueous solution or the water content in dilute sulfuric acid.

Also, the amount of decrease in the electrolyte measured through the test is as shown in Table 1, and regarding the maintenance-freeness, comparing conventional battery A with each test battery, the effect of improving the performance is also obtained in the liquid reduction rate per unit time. As a result, it is possible to reduce the frequency of water replenishment when used at high temperatures.

In the present embodiment, an example in which an antimony-based lead alloy is used for the anode grid is explained, but the same effect can be expected in a paste type electrode plate in which a lead alloy practically containing no antimony is used for the grid alloy.

EFFECTS OF THE INVENTION As described above, according to the present invention, it is possible to improve the durability of a lead storage battery in a high temperature atmosphere, and further improve the maintenance-free performance represented by the frequency of rehydration, which is of great industrial value. It is a thing.

[Brief description of drawings]

 The drawing is a curve diagram showing battery characteristics during continuous overcharge.

Claims (1)

[Claims] 1. A method for producing a paste-type lead storage battery electrode plate, which is produced by kneading lead powder consisting of lead oxide and residual lead obtained by oxidizing lead or a lead alloy with dilute sulfuric acid, and solubility in kneading with dilute sulfuric acid. A process for producing a lead-acid battery electrode plate, which comprises kneading dilute sulfuric acid with a pre-kneaded lead powder having a free water content, which is kneaded using an aqueous solution having a silica content of 10 to 80 mg /.