JP2005044703A - Manufacturing method of control valve type lead storage battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control valve type lead storage battery of which it is easy to manufacture a positive electrode plate, and with high-rate discharge capacity increased. <P>SOLUTION: A paste-like active material is filled in a lattice of a cast method, dipped in diluted sulfuric acid, dipped in sodium silicate aqueous solution, and afterwards, is aged and dried to form a layer of silica on the surface of the positive electrode plate. Here, dipping is made with the diluted sulfuric acid with a specific weight of around 1.050 and the sodium silicate aqueous solution with a sodium silicate concentration of of 1 to 5% by mass. The control valve type lead storage battery is manufactured with the use of this positive electrode plate, a negative electrode plate and a retainer made of glass fiber as used in the past. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a control valve type lead storage battery.

  Control valve-type lead-acid batteries are widely used in uninterruptible power supplies, power storage, automobile batteries, and the like because they have the feature of being inexpensive and highly reliable. Recently, there has been a strong demand for an increase in high-rate discharge capacity and high output of control valve type lead-acid batteries. In addition, it is known that the high rate discharge capacity of the control valve type lead-acid battery is limited by the difficulty of moving the electrolytic solution between the retainer and the positive electrode plate.

  The movement of the electrolytic solution between the retainer and the positive electrode plate strongly depends on the interface contact structure between the retainer and the positive electrode plate. Therefore, conventionally, as a means for increasing the high rate discharge capacity and increasing the output, a method of increasing the pressure between the retainer and the positive electrode plate has been used.

  Recently, in order to increase the high-rate discharge capacity and output of a control valve type lead-acid battery, an expanded grid was used and a paste paper impregnated with sodium silicate was applied to the surface of a positive electrode plate filled with a paste-like active material. A method of attaching is studied (for example, refer to Patent Document 1).

Japanese Patent Laid-Open No. 9-231996

  However, although the technique disclosed in Patent Document 1 described above is convenient when an electrode plate is continuously produced as in the case of using an expanded lattice, the electrode is formed in the case of using a cast-type lattice. There is a problem that the production of the board becomes difficult.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a control valve type lead-acid battery excellent in high-rate discharge characteristics in a positive electrode plate using a casting type grid.

  In order to solve the above-described problems, a control valve type lead-acid battery according to the present invention uses a casting type positive electrode grid, is filled with a paste-like active material, is immersed in sulfuric acid, and is immersed in an aqueous sodium silicate solution. It is characterized by using.

  That is, the invention described in claim 1 is a method for manufacturing a control valve type lead-acid battery using a positive electrode plate manufactured by manufacturing a grid for a positive electrode by a casting method and filling a paste-like active material. It is characterized by using a positive electrode plate that is filled with a substance, dipped in dilute sulfuric acid, dipped in a sodium silicate aqueous solution, and then aged and dried.

  The invention described in claim 2 is characterized in that, in the invention described in claim 1, the concentration of sodium silicate in the sodium silicate aqueous solution is 1 to 5% by mass.

  When the present invention is used, a control valve type lead-acid battery that is easy to manufacture and has an increased high rate discharge capacity can be provided, which is industrially superior.

  Hereinafter, the control valve type lead storage battery according to the present invention will be described in detail.

1. Preparation of positive electrode plate and negative electrode plate The paste-type positive electrode plate according to the present invention was manufactured by a manufacturing process as shown in FIG. That is, a positive electrode lattice is produced by a casting method by a conventional method and filled with a paste-like active material. Next, in the control valve type lead acid battery according to the present invention, it is immersed in dilute sulfuric acid having a specific gravity of 1.050 and immersed in a sodium silicate aqueous solution having a concentration described later. Thereafter, aging and drying were performed by a conventional method to obtain an unformed positive electrode plate. On the other hand, what was used conventionally was used as a negative electrode plate.

2. Manufacture conditions and test conditions of control valve type lead acid battery The control valve type lead acid battery was produced by the method currently used conventionally. That is, three unformed positive electrode plates and four unformed negative electrode plates are laminated and welded through a glass fiber retainer that has been conventionally used to produce a group of electrode plates, Insert into. Then, a lid is attached to the battery case, and dilute sulfuric acid having a specific gravity of 1.21 is injected, and the battery case is formed at an ambient temperature of about 40 ° C. and a charge amount of about 250% for 60 hours. A 7 Ah control valve type lead acid battery was manufactured.

  The manufactured control valve type lead acid battery was discharged at 25 ° C. with a relatively large current value of 21A (3CA) (high rate discharge), and the discharge end time was set to 1.3 V and the discharge time was measured.

  Hereinafter, embodiments according to the present invention will be described in detail.

(Examples 1-3)
As shown in FIG. 1, a positive electrode grid is produced by casting, filled with a paste-like active material, immersed in dilute sulfuric acid having a specific gravity of about 1.050, and sodium silicate is added in an amount of 1% by mass, 5% by mass, It was immersed in an aqueous solution (sodium silicate aqueous solution) in which 10% by mass was dissolved and aged and dried by a conventional method to obtain three types of unformed positive plates (in Table 1, Examples 1 to 3, respectively). .) By performing such treatment, a silica layer can be formed on the surface of the positive electrode plate with a relatively simple technique and manufacturing apparatus. Other control valve type lead-acid battery manufacturing conditions, test conditions, etc. are as described above.

(Comparative example)
As a comparative example, an unformed positive electrode plate which has not been immersed in dilute sulfuric acid or sodium silicate and has been conventionally used was used. Other control valve type lead-acid battery manufacturing conditions, test conditions, etc. are as described above.

  Table 1 shows the results of measuring the 3CA discharge time of the above four types of control valve type lead-acid batteries. It is recognized that the control valve type lead storage battery according to the present invention has a longer discharge time and is superior in high rate discharge characteristics than the control valve type lead storage battery of the comparative example. The reason for this is not clear, but it is thought that by forming a silica layer on the surface of the positive electrode plate, the adhesion between the positive electrode plate and the retainer is improved, and as a result, the electrolyte solution is easily moved. .

  In addition, from Table 1, although the discharge time when the concentration of the sodium silicate aqueous solution is 10% by mass (Example 3) is increased as compared with the comparative example (without addition), details are not shown. The discharge average voltage dropped slightly, and an undesirable tendency was observed. Although the details of this reason are not clear, it is considered that the movement of the electrolytic solution is inhibited by a large amount of the silica layer formed on the surface of the positive electrode plate. Therefore, it can be said that the concentration of the sodium silicate aqueous solution is more preferably 1 to 5% by mass.

  As described above, when the manufacturing method according to the present invention is used, a casting type lattice can be used. In addition, since it is only immersed in dilute sulfuric acid and sodium silicate aqueous solution, the manufacturing equipment can be simplified.

  By using the present invention, it is possible to provide a control valve type lead-acid battery that is easy to manufacture and has an increased high rate discharge capacity.

It is the schematic which shows the manufacturing process of the paste type positive electrode plate concerning this invention.

Claims (2)

In a manufacturing method of a control valve type lead-acid battery using a positive electrode plate manufactured by manufacturing a grid for a positive electrode by casting and filling a paste-form active material, the paste-form active material is filled in the grid and diluted sulfuric acid A control valve type lead-acid battery manufacturing method characterized by using a positive electrode plate which has been immersed in an aqueous solution of sodium silicate and then aged and dried. The method for manufacturing a control valve type lead-acid battery according to claim 1, wherein the concentration of sodium silicate in the aqueous sodium silicate solution is 1 to 5 mass%.

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