JPH06275255A - Manufacture of sealed lead-acid battery - Google Patents

Abstract

PURPOSE:To manufacture a lead-acid battery having a high-rate discharge characteristic and a long life by increasing the formation property for battery jar formation. CONSTITUTION:An active material paste kneaded with the lead oxide powder containing minium, sulfuric acid, and water is filled in a current collector to form an undried positive electrode plate, and the undried positive electrode plate is aged and dried to manufacture an unformed positive electrode plate. The unformed positive electrode plate and an unformed negative electrode plate are combined to form an electrode plate group, and the electrode plate group is arranged in a battery jar and formed via battery jar formation. The quantity of minium and the processing condition of the aging/drying processes are determined so that tetrabasic lead sulfate and lead dioxide are mixedly contained in the unformed positive electrode plate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a sealed lead acid battery.

[0002]

2. Description of the Related Art Generally, in order to manufacture a sealed lead acid battery,
An active material paste prepared by kneading lead oxide powder such as lead monoxide and sulfuric acid and water is filled in a collector such as a cast or expanded grid body to form an undried electrode plate. Then, the undried electrode plate is aged to generate tribasic lead sulfate in the active material and then dried to form an unformed electrode plate, which is completed by chemical conversion. To form an unformed electrode plate, combine the unformed anode plate and unformed cathode plate in order to make the manufacturing location of the sealed lead-acid battery as small as possible and to shorten the time to dry the electrode plate after forming. A large number of battery case formations are performed in which the formed electrode plates are formed in a battery case. However, the sealed lead-acid battery has a limit in the amount of electrolytic solution at the time of chemical formation, and the electrolytic solution is impregnated in the electrolytic solution holder. Therefore, even if the unformed anode plate is formed by the battery case formation, the electrolytic solution is difficult to diffuse into the active material of the anode plate, and there is a problem that the forming property is poor. Therefore, it was considered to make an anode plate by using a mixture of lead oxide powder, which is a raw material of the active material paste, with lead dioxide which is converted into conductive lead dioxide (PbO2) by reacting with sulfuric acid.

[0003]

If lead oxide powder mixed with lead oxide is used, the conversion efficiency of the anode plate is improved and the cost effectiveness is improved, but the binding force between the active materials is weakened. However, there is a problem that the battery life is shortened. Further, the battery manufactured by such a method could not improve the effect of high rate discharge performance even when used for a battery such as a battery for an uninterruptible power supply (UPS) which requires high rate discharge performance.

An object of the present invention is to provide a method for producing a lead storage battery having a high high rate discharge performance and a long life by enhancing the chemical conversion property in battery case formation.

[0005]

According to the first aspect of the present invention, a current collector is filled with an active material paste obtained by kneading lead oxide powder containing lead tin oxide, sulfuric acid and water to form a undried anode plate. An active material paste filling step to make and an electrode plate group constituted by combining an unformed anode plate manufactured by an aging drying step of drying after drying the undried anode plate and an unformed cathode plate are arranged in a battery case, Targeting the method for manufacturing a sealed lead-acid battery by forming an unformed anode plate and an unformed cathode plate by battery case formation, the amount of lead and the treatment conditions of the aging and drying process are set to 4 bases in the unformed anode plate. It is specified that mixed lead sulfate and lead dioxide are mixed.

According to the second aspect of the invention, the content of lead tin in the active material paste is 10 to 60% by weight, and 15 to 60% by weight of tetrabasic lead sulfate is produced in the unformed anode plate.

[0007]

[Function] Tetrabasic lead sulfate has a larger crystal structure than tribasic lead sulfate. Therefore, as in the invention of claim 1, when the amount of red lead and the treatment conditions of the aging and drying step are determined so that tetrabasic lead sulfate and lead dioxide are mixed in the unformed anode plate, tetrabasic sulfuric acid is obtained. Since lead has large prismatic crystals, tetrabasic lead sulfate serves as the skeleton of the anode active material of the unformed electrode plate, and the active material of the unformed anode plate has a structure having large pores. As a result, it is possible to enhance the diffusivity of the electrolytic solution into the inside of the active material of the unformed anode plate and perform the battery case formation. In addition, since lead dioxide (PbO2) produced by lead oxide having high conductivity is present in the unformed anode plate from the early stage of formation, the conversion efficiency of the battery is greatly improved. Also,
Since the anode active material has large pores even after chemical formation,
It is possible to enhance the high-rate discharge characteristics of the battery, in which the diffusion of the electrolytic solution into the anode active material is the controlling factor. Further, since the anode active material has a skeleton structure, it is possible to prevent the anode active material from becoming muddy at an early stage due to charge / discharge cycles, and to extend the life of the battery.

According to the second aspect of the present invention, it is possible to effectively improve the chemical conversion property and manufacture a lead acid battery having a high high rate discharge characteristic and a long life.

[0009]

The method for manufacturing a sealed lead-acid battery according to an embodiment of the present invention will be described in detail below.

First, an active material paste is prepared by kneading lead oxide powder consisting of lead oxide and lead monoxide in a weight ratio of 2: 3, sulfuric acid and water to prepare a current collector comprising a cast grid. Filled to make undried anode plates. In addition, sulfuric acid and water were added in amounts such that lead sulfate in the active material paste was 16% by weight. Next, this undried anode plate was placed in an atmosphere of 30 ° C. and 98 RH% for 4 hours.
After being left standing for 80 hours, it was left standing in an atmosphere of 80 ° C. and 98 RH% for 2 hours for aging, and then dried at 60 ° C. for 13 hours to prepare an unformed anode plate. When the composition of the active material of this unformed anode plate was examined by X-ray diffraction, the diffraction intensity ratio of tribasic lead sulfate and tetrabasic lead sulfate was 1: 1. Next, three unformed anode plates and four well-known unformed cathode plates are laminated via a retainer to form an electrode plate group, and this electrode plate group is incorporated in a battery case to inject a prescribed electrolytic solution. Then, the theoretical amount of electricity is 20 in 13 hours.
Chemical conversion was performed to 0%. Then, this was discharged at 3.1 A for 1 hour and then charged at 1.1 A for 6 hours to give 6.5 A.
The H-2V sealed lead acid battery was completed.

Next, in order to investigate the characteristics of the sealed lead acid battery manufactured by the method of this embodiment, two kinds of sealed lead acid batteries a,
b was prepared and tested. The sealed lead-acid battery a is a battery manufactured by the method of this embodiment. The sealed lead-acid battery b is a battery manufactured by a conventional method, and the undried positive electrode plate
After leaving it in an atmosphere of 8 RH% for 24 hours, 40 ° C., and then 9
It was left to stand in an atmosphere of 8 RH% for 24 hours for aging, and then dried at 50 ° C. for 16 hours to prepare an unformed anode plate. Otherwise, it was manufactured by the same method as in this example. When the composition of the active material of this unformed anode plate was examined by X-ray diffraction, the presence of tetrabasic lead sulfate was not recognized.

The batteries a and b were discharged at a final voltage of 1.3 V at 19.5 A, and the discharge characteristics of each battery were examined. FIG. 1 shows the measurement result. From this figure, it can be seen that the discharge capacity of the battery can be increased by manufacturing by the method of this embodiment.

Next, the batteries a and b were discharged at 25 ± 2 ° C. for 2 hours at 0.25 CA and then charged / discharged for 6 hours at 0.1 C to examine the cycle life characteristics of each battery. The characteristics of each battery were 0.50 every 50 cycles.
It was determined by discharging at 25C (final voltage is 1.7V) and measuring the discharge time. FIG. 2 shows the measurement result.

It can be seen from this figure that the life of the battery can be extended by manufacturing it by the method of this embodiment.

Next, the relationship between the amount of lead tin and the discharge characteristics of the battery was investigated by changing the amount of lead tin contained in the active material paste of batteries a and b. FIG. 3 shows the measurement result. From this figure, the amount of red lead contained in the active material paste is 10 to 60.
It can be seen that the discharge characteristics of the battery can be improved by adjusting the weight percentage.

[0016]

According to the first aspect of the present invention, the amount of lead tin and the treatment conditions of the aging and drying step are determined so that tetrabasic lead sulfate and lead dioxide are mixed in the unformed anode plate. Basic lead sulfate serves as the skeleton of the anode active material of the unformed electrode plate. Moreover, since highly conductive lead dioxide remains in the unformed anode plate, the conversion efficiency of the battery is significantly improved. Also,
Since the anode active material has large pores even after chemical formation,
The high rate discharge characteristics of the battery can be improved. Further, since the active material has a skeleton structure, the life of the battery can be extended.

According to the second aspect of the present invention, it is possible to effectively improve the chemical conversion property to manufacture a lead acid battery having a high high rate discharge characteristic and a long life.

[Brief description of drawings]

FIG. 1 is a diagram showing discharge characteristics of a battery used in a test.

FIG. 2 is a diagram showing cycle life characteristics of a battery used in a test.

FIG. 3 is a diagram showing the relationship between the amount of lead tin contained in the active material paste and the discharge characteristics of the battery.

Claims (2)

[Claims] 1. An active material paste filling step of filling a current collector with an active material paste obtained by kneading lead oxide powder containing lead tin oxide, sulfuric acid and water to prepare a undried anode plate, and the undried drying step. An unformed anode plate is manufactured by an aging drying step of drying after aging the anode plate, and a plate group constituted by combining the unformed anode plate with an unformed cathode plate is placed in a battery case, and the unformed In the method of manufacturing a sealed lead-acid battery by forming an anode plate and an unformed cathode plate by battery formation, the amount of lead tin and the treatment conditions of the aging drying step are tetrabasic in the unformed anode plate. A method for manufacturing a sealed lead-acid battery, characterized in that lead sulfate and lead dioxide are mixed. 2. The content of lead tin in the active material paste is set to 10 to 60% by weight, and 15 to 60% by weight of tetrabasic lead sulfate is formed in the unformed anode plate. 1. The method for manufacturing the sealed lead storage battery according to 1.