JPH05258746A - Pole plate of lead-acid storage battery and manufacture thereof - Google Patents

Abstract

PURPOSE:To provide excellent charge/discharge service life by producing a uniform paste through making control of a mixer in a pole plate of a lead-acid storage battery and a manufacturing method therefor. CONSTITUTION:In a lead-acid storage battery whose pole plate paste is produced by mixing lead oxide, water, dilute sulfuric acid, etc., by an agitation-mix type mixer, the pole plate paste particles having a particle size of less than 250mum are set at 90% or more by weight ratio with respect to the pole plate paste particles. Further, the specific surface area of non-activated substance after ageing and desiccation is set to range from 1.5m<2>/g to 3.5m<2>/g. Thus, a pole plate paste production method is realized in which this control is completed through deciding a condition of being mixed from variation in the motor load.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead-acid battery electrode plate and a method for manufacturing the same.

[0002]

2. Description of the Related Art Heretofore, an electrode plate paste for a lead storage battery has been prepared by mixing lead oxide with water, dilute sulfuric acid and various additives. Then, the temperature of the electrode plate paste during mixing rises due to the exothermic reaction caused by the reaction of lead oxide and dilute sulfuric acid, and the composition of the electrode plate paste that is completed may become non-uniform due to evaporation and separation of water or nonuniform reaction. In many cases, the particle size of the produced electrode plate paste was not uniform, and it was difficult to make the electrode plate paste uniform. Further, in order to suppress the exothermic reaction, a method of slowing the addition rate of sulfuric acid and prolonging the mixing time, a method of cooling the mixer by water cooling, etc., or a method of adding water and dilute sulfuric acid as a mixed material after cooling them beforehand And so on.
However, these mixing methods have problems such as inefficiency and costly cooling.

[0003]

The problem with the conventional lead-acid battery electrode plate and its manufacturing method is that the temperature of the electrode plate paste during mixing rises due to the exothermic reaction of the reaction between lead oxide and dilute sulfuric acid, and the evaporation of water Separation or heterogeneity of the reaction
The composition of the finished electrode plate paste becomes uneven,
Alternatively, the particle size of the generated electrode plate paste is often non-uniform, which causes variations in the amount of water in the electrode plate paste, resulting in variations in the bond between the particles of the unactivated active material after aging and drying. Was to occur. And variations in the particle size of these electrode plate pastes or variations in the binding of the non-activated material cause a decrease in the cycle life of repeated charge and discharge when the lead storage battery is completed, and the battery life is short. Was causing it.

The present invention solves the above conventional problems,
An object of the present invention is to provide an electrode plate having a paste that does not reduce the charge / discharge cycle life when assembled into a lead storage battery by a reliable means, and a method for manufacturing the same.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, the present invention has a particle size of the electrode plate paste of a lead storage battery in which particles smaller than 250 μm have a particle size smaller than that of the entire electrode plate paste. The weight ratio is 90% or more.

The specific surface area of the unformed active material after aging and drying is 1.5 m ² / g to 3.5 m ² / g.

Then, the load power or load current of the stirring motor of the mixer for kneading and mixing lead oxide, dilute sulfuric acid and water as main components is measured, and the load of the stirring motor is
A method for manufacturing an electrode plate for a lead storage battery, comprising a step of stirring and mixing until 90% or more of particles in the electrode plate paste to be mixed have a diameter of less than 250 μm and have a stirring motor-specific value. is there.

Further, the stirring / mixing process is controlled by the load of the stirring motor to perform stirring / mixing in which the specific surface area of the unformed active material after aging and drying is 1.5 m ² / g to 3.5 m ² / g. This is a method for manufacturing a lead-acid battery electrode plate having steps to be performed.

[0009]

When a mixer that does not allow water to escape during mixing of the electrode plate paste is used, the load on the stirring motor of the mixer causes
Since the mixed state of the electrode plate paste is observed, the change in the density of the electrode plate paste, that is, the change in the particle size can be read as the load of the stirring motor. As a result, when the mixing is terminated when the particle size becomes optimum and the load on the stirring motor is stabilized after being made uniform, it is possible to obtain an electrode plate paste having a uniform composition. The particle size of the electrode plate paste determines the specific surface area of the unformed active material after aging and drying. Therefore, when the electrode plate of the lead storage battery is manufactured using the electrode plate paste thus obtained, the retention property of the water content in the electrode plate paste is improved as compared with the conventional electrode plate paste with particles having large variations. Therefore, the aging reaction can be uniformly progressed, and tribasic lead sulfate having excellent bonding between the active material particles can be obtained. The charge / discharge cycle life of the lead acid battery using these electrode plates is superior to that of the conventional lead acid battery.

[0010]

An embodiment of the present invention will be described below with reference to the drawings.

The electrode plate paste of the embodiment is manufactured by a blade type mixer. The load fluctuation of the motor during mixing and the percentage (weight ratio) of paste particles at that time on a sieve having a mesh size of 250 μm are shown in FIG. 1 and 2
As is clear from FIG. 3 and FIG. 3, there is a correlation between the motor load and the distribution of the paste particle size, and also the specific surface area of the unactivated material at that time. It is possible to manufacture various pastes and unformed electrode plates.

The unformed electrode plate made of the electrode plate paste thus obtained has a specific surface area of the active material of 1.5 to
Since it is almost constant at 3.5 m ² / g, the uniformity of the active material is supported.

In the embodiment, 5 kg of water is added to 500 kg of lead oxide.
The results are shown when 500 liters of dilute sulfuric acid having a specific gravity of 1.40 and 00 liters were used, but the same results as those shown in the examples were obtained even when the ratio of water and dilute sulfuric acid was changed.

FIG. 4 shows the results of the cycle life test of the battery prepared by using these electrode plates. The battery has a nominal voltage of 12 V and a nominal capacity of 2.0 AH, and is charged at a constant voltage of 1
The discharge was performed at 4.7 V / 0.8 A for 6 hours, the discharge was 16 ohms, and the discharge end voltage was 10.5 V. As is clear from FIG. 4, the cycle life characteristics of the battery made from the paste of the present invention in which the paste particles are uniformly mixed and stirred are good.

Although the load power fluctuation is shown in the embodiment, the present invention can be realized by obtaining the relationship with the current if the load is shown.

[0016]

As described above, according to the present invention, it is possible to manufacture a uniform electrode plate paste, and the cycle life of a lead acid battery manufactured using the obtained electrode plate is excellent. The effect is extremely large.

[Brief description of drawings]

FIG. 1 is a diagram showing a load (electric power) of a stirring / mixing motor and a ratio of particles in the electrode plate paste in the electrode plate paste manufacturing state.

FIG. 2 is a diagram showing a correlation between a motor load and a ratio of particles in the paste.

FIG. 3 is a diagram showing the relationship between the specific surface area of paste particles and the non-active material.

FIG. 4 is a diagram showing an example of battery characteristics of charge / discharge cycle life by batteries of an example of the present invention and a conventional example.

Claims (4)

[Claims] 1. An electrode plate paste mainly composed of lead oxide, dilute sulfuric acid and water, wherein the particle size of the electrode plate paste is smaller than 250 μm with respect to the particles of the whole electrode plate paste. A lead acid battery electrode plate filled with an electrode plate paste having a ratio of 90% or more. 2. A lead-acid battery electrode plate in which the specific surface area of the unformed active material after aging and drying of the electrode plate is 1.5 m ² / g to 3.5 m ² / g. 3. The load of a stirring motor of a mixer which mainly mixes lead oxide, dilute sulfuric acid, and water is measured, and the measured load of the stirring motor is a weight ratio in the electrode plate paste to be mixed. A method for producing a lead-acid battery electrode plate, which comprises a step of stirring and mixing until 90% or more of the particles have a diameter smaller than 250 μm and the stirring motor has a stable value. 4. The specific surface area of the non-activated material after the scholarship drying is 1.5 m ² / g to 3. depending on the load of a stirring motor of a mixer that mainly mixes lead oxide, dilute sulfuric acid, and water.
A method for manufacturing a lead-acid battery electrode plate, which comprises a stirring / mixing step of controlling to 5 m ² / g.