JP2010113932A - Electrode plate for lead-acid storage battery and control valve type lead-acid storage battery using this - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lead-acid storage battery capable of shortening the time of injection process of an electrolyte by suppressing a dendrite short circuit, even under a condition of charging immediately after liquid injection. <P>SOLUTION: A plurality of grooves 2 are installed nearly perpendicularly at only the center part in width direction so that the electrolyte solution may be filled into the electrode plate 1 uniformly in a short time, and the grooves 2 are not installed in substance at a site 3 other than this center part in width direction. It is more preferable that the depth of the grooves 2 is 2-100 μm from the view points of sufficiently utilizing a capillary action. The width of the center part in width direction is made to be 20-60% against the total width of the electrode plate 1. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrode plate for a lead storage battery and a control valve type lead storage battery using the same.

  Since the control valve type lead acid battery has a larger number of positive electrodes and negative electrodes than the conventional liquid lead acid battery, it is necessary to set a small distance between the positive electrode and the negative electrode (electrode plate interval). It is known that the small distance between the electrode plates causes a dendrite short due to elution of lead ions during charging following the step of injecting sulfuric acid as an electrolyte.

Therefore, as in Patent Document 1, boric acid is present inside a separator mainly composed of glass fiber, so that boric acid remaining as a solid when the concentration of the electrolyte is increased by charging hinders the growth of dendrites. It has been studied to function usefully as a short-circuit preventing agent.
JP 2003-338271 A

  However, even if the technique of Patent Document 1 is utilized, it cannot be said that the effect is sufficient in the condition that charging is performed immediately after injection.

  The present invention solves the above-mentioned problems, and provides a lead-acid battery that can suppress dendrite short-circuiting even under the condition that charging is performed immediately after injection, and can shorten the time required for injecting the electrolyte. With the goal.

  In order to solve the above-mentioned problem, the invention according to claim 1 of the present invention is provided with a groove substantially perpendicularly only at the center part in the width direction of at least one side, and substantially provided with a groove other than the center part in the width direction. The present invention relates to an electrode plate for a lead-acid battery, characterized in that it is not provided.

  The invention according to claim 2 of the present invention is characterized in that, in the electrode plate for a lead storage battery according to claim 1, the width of the central portion in the width direction is 20 to 60% with respect to the entire width of the electrode plate. And

  The invention according to claim 3 of the present invention is characterized in that, in the electrode plate for a lead storage battery according to claim 2, a plurality of grooves are provided in the central portion in the width direction.

  The invention according to claim 4 of the present invention relates to a control valve type lead-acid battery using the electrode plate according to any one of claims 1 to 3 as at least one of a positive electrode and a negative electrode, and having a mat separator.

As a result of intensive studies, the inventors have discovered that the cause of dendritic short-circuiting is that lead ions elute into the electrolyte from the center in the width direction of the electrode plate mainly composed of tribasic lead sulfate, and electrons are discharged from the negative electrode when energized. It was received and deposited as metallic lead and found to reach the positive electrode. In addition, it has been found that there is a variation in the penetration of sulfuric acid into the electrode plate as one of the causes of lead ions dissolving from the electrode plate. Specifically, since the control valve type lead-acid battery has a small distance between the electrode plates, the penetration of sulfuric acid, which is an electrolyte, tends to vary, and the specific gravity decreases (lower sulfuric acid concentration) as it approaches the center in the width direction of the electrode plate, It was found that tribasic lead sulfate (which is easier to dissolve as the sulfuric acid concentration is lower) melts at the center in the width direction, causing the above-mentioned dendrite short circuit. In order to avoid this phenomenon, it is necessary to inject the electrolyte solution for a long time until the sulfuric acid completely soaks, but the productivity is lowered.

  The present invention is based on the above-described new knowledge, and a groove is provided substantially perpendicularly only at the central portion in the width direction of the electrode plate so that the electrolyte solution penetrates the electrode plate evenly in a short time. Except for the central portion in the direction, substantially no groove is provided.

  According to the present invention, it is possible to provide a lead-acid battery that can suppress a dendrite short even under a condition of charging after injection, and can shorten the time required for injecting the electrolyte.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic view of an electrode plate for a lead storage battery according to the present invention, and FIG. 2 is a cross-sectional view of the electrode plate for a lead storage battery according to the present invention. The electrode plate for a lead-acid battery according to claim 1 of the present invention is provided with a groove substantially perpendicularly only at least in the widthwise central portion of one side, and the groove 3 is substantially formed in a portion 3 other than the widthwise central portion. It is characterized by not providing it.

  A dendrite short is that lead ions elute into the electrolyte from the center in the width direction of the electrode plate 1 made mainly of tribasic lead sulfate, and when it is energized, it receives electrons from the negative electrode and precipitates as metallic lead. It is thought to be the main cause of outbreak. The main reason for the dissolution of lead ions from the electrode plate 1 is that there is variation in the penetration of sulfuric acid into the electrode plate 1. Specifically, in particular, a control valve type lead-acid battery has a small interval between the electrode plates 1, so that the penetration of sulfuric acid, which is an electrolytic solution, is likely to vary. It is considered that tribasic lead sulfate (which is more easily dissolved as the sulfuric acid concentration is lower) melts in the center portion in the width direction, and the dendrite short circuit described above is caused. In order to avoid this problem, it is sufficient to inject the electrolytic solution for a long time until the sulfuric acid completely soaks, but the productivity is lowered. Therefore, in the present invention, a groove 2 is provided substantially perpendicularly only at the central portion in the width direction so that the electrolyte soaks uniformly into the electrode plate 1 in a short time, and the groove 3 is substantially formed in the portion 3 other than the central portion in the width direction. 2 is not provided.

  The depth of the groove 2 in the present invention is preferably 2 to 200 μm although it depends on the thickness of the electrode plate 1, and more preferably 2 to 100 μm from the viewpoint of fully utilizing the capillary phenomenon. In the present invention, “substantially no groove 2 is provided in the portion 3 other than the central portion in the width direction” means that a groove-like scratch or the like that is unexpectedly generated when the electrode plate 1 is mechanically conveyed is intentionally The groove-like scratch is not recognized as the groove 2 when the groove 2 is significantly shallower than the groove 2 (for example, the depth is 1/10 or less of the groove 2).

  With the above configuration, when pouring sulfuric acid as an electrolytic solution, sulfuric acid is soaked from the central portion in the width direction of the electrode plate 1 so that sulfuric acid having a low specific gravity does not exist locally, and dendritic shorts can be eliminated. .

  The invention according to claim 2 of the present invention is such that the width of the central portion in the width direction is 20 to 60% of the entire width of the electrode plate 1 in the electrode plate 1 for the lead storage battery of claim 1. It is characterized by. If the width of the central portion in the width direction constituted by one or a plurality of grooves 2 is less than 20% of the total width of the electrode plate 1, the area of the central portion in the width direction is insufficient, and if it exceeds 60%, the width direction It becomes difficult to selectively introduce sulfuric acid only to the central portion, and in any case, it becomes somewhat difficult to eliminate the dendrite short as originally intended.

  The central part in the width direction can be defined as follows. First, when the number of the grooves 2 is one, the width of the grooves 2 itself is indicated. In addition, when there are a plurality of grooves 2, it indicates the width connecting the outermost ends of each of the outermost grooves 2, and includes a flat portion (no grooves 2) sandwiched between the grooves 2.

  The invention according to claim 3 of the present invention is characterized in that, in the electrode plate 1 for a lead storage battery according to claim 2, a plurality of grooves 2 are provided in the central portion in the width direction. In order to form a central portion in the width direction of 20 to 60% with respect to the entire width of the electrode plate 1 using the grooves 2 that can exhibit sufficient capillary action, it is preferable to provide a plurality of grooves 2.

  The invention which concerns on Claim 4 of this invention is related with the control valve type lead acid battery which used the electrode plate 1 in any one of Claims 1-3 as at least one of a positive electrode or a negative electrode, and was equipped with the mat | matte separator. The electrode plate 1 according to any one of claims 1 to 3 is used as at least one of a positive electrode and a negative electrode, and a mat separator is interposed between the positive electrode and the negative electrode. It is possible to provide a control valve type lead-acid battery that can suppress the time required for the step of injecting the electrolytic solution.

Example 1
An active material made of lead and an additive was filled in an expanded lattice made of lead to produce a positive electrode having a thickness of 1.1 mm and a width of 97.5 mm. On the other hand, lead and an additive active material were filled in an expanded lattice made of lead to produce a negative electrode having a thickness of 0.9 mm and a width of 97.5 mm. A groove with a width of 100 μm (pitch width: 1.0 mm) is formed in the center in the width direction of these positive and negative electrodes by a press machine, and the width connecting the outermost ends of the outermost grooves is 19.5 mm (the center in the width direction). The width of the portion is 10% of the entire width of the electrode plate. The 11 positive electrodes and 12 negative electrodes processed in this way were opposed to each other with a mat separator (glass mat separator, 0.95 mm) interposed therebetween to form an electrode plate group. The six electrode plates are inserted into a transparent polypropylene battery case divided into six chambers and connected in series. After injecting an electrolytic solution made of sulfuric acid, a polypropylene lid is attached to control 12V60Ah. A valve-type lead acid battery was produced.

(Example 2)
The width that connects the outermost ends of the outermost grooves to the center in the width direction of the positive electrode and the negative electrode is 19.5 mm (the width in the center in the width direction is 20% of the total width of the electrode plate). A 12V60Ah control valve type lead-acid battery was produced in the same manner as in Example 1 except that a 100 μm groove (pitch width 1.0 mm) was formed.

(Example 3)
The width that connects the outermost ends of the outermost grooves to the center in the width direction of the positive electrode and the negative electrode is 39.0 mm (the width in the center in the width direction is 40% of the total width of the electrode plate). A 12V60Ah control valve type lead-acid battery was produced in the same manner as in Example 1 except that a 100 μm groove (pitch width 1.0 mm) was formed.

Example 4
Width so that the outermost end of each of the outermost grooves is connected to the central portion in the width direction of the positive electrode and the negative electrode is 58.5 mm (the width of the central portion in the width direction is 60% of the total width of the electrode plate). A 12V60Ah control valve type lead-acid battery was produced in the same manner as in Example 1 except that a 100 μm groove (pitch width 1.0 mm) was formed.

(Example 5)
The width connecting the outermost ends of the outermost grooves to the center in the width direction of the positive electrode and the negative electrode is 68.3 mm (the width in the width direction center is 70% of the total width of the electrode plate). A 12V60Ah control valve type lead-acid battery was produced in the same manner as in Example 1 except that a 100 μm groove (pitch width 1.0 mm) was formed.

(Comparative Example 1)
A 12V60 Ah control valve type lead-acid battery was produced in the same manner as in Example 1 except that grooves having a width of 100 μm (pitch width: 1.0 mm) were formed on the entire surfaces of the positive electrode and the negative electrode.

(Comparative Example 2)
A control valve type lead-acid battery of 12V60Ah was produced in the same manner as in Example 1 except that grooves (pitch width 1.0 mm) were not formed in the positive electrode and the negative electrode.

(Comparative Example 3)
The width that connects the outermost ends of the outermost grooves to only one side of the positive electrode and the negative electrode is 39.0 mm (the width of the central portion in the width direction is 40% of the entire width of the electrode plate). A 12V60Ah control valve type lead-acid battery was produced in the same manner as in Example 1 except that a 100 μm groove (pitch width 1.0 mm) was formed.

  Each of these control valve-type lead-acid batteries was 100 pieces. Since each battery is composed of six cells, 600 cells are prepared for each of Examples 1 to 5 and Comparative Examples 1 to 3 of the present invention. In each cell, a dilute sulfuric acid electrolyte solution having a conversion density of 1.300 at 20 ° C. was injected, and each battery was disassembled one hour after the injection, thereby confirming the incidence of dendrite shorts in each cell. . These results are shown in Table 1.

  From the result shown in Table 1, compared with the control valve type lead acid battery of Examples 1-3, the control valve type lead acid battery of Examples 1-5 which provided the groove only in the width direction central part of the positive electrode and the negative electrode It can be seen that the incidence of dendrite shorts is reduced. Therefore, by forming a groove in the central portion in the width direction of at least one of the positive electrode and the negative electrode, it can be seen that a dendrite short circuit due to lead ions is less likely to occur even when the electrolyte is rapidly injected as in this embodiment. .

  According to the configuration of the present invention, it is possible to provide a control valve type lead storage battery in which a dendrite short-circuit due to lead ions hardly occurs even when an electrolyte is rapidly injected, which is extremely useful industrially.

Overview of the lead-acid battery plate of the present invention Sectional drawing of the electrode plate for lead acid batteries of this invention

Explanation of symbols

1 Electrode plate 2 Groove 3 Parts other than the center in the width direction

Claims (4)

An electrode plate for a lead storage battery, characterized in that a groove is provided substantially perpendicularly only at the center in the width direction on at least one side, and no groove is provided substantially other than in the center in the width direction. The electrode plate for a lead-acid battery according to claim 1, wherein the width of the central portion in the width direction is 20 to 60% with respect to the entire width of the electrode plate. The electrode plate for a lead storage battery according to claim 2, wherein a plurality of the grooves are provided in the central portion in the width direction. A control valve type lead-acid battery using the electrode plate according to any one of claims 1 to 3 as at least one of a positive electrode and a negative electrode, and comprising a mat separator.

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