JPH1079261A - Sealed lead storage battery - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve the ability of a negative electrode plate to absorb oxygen gas generated from a positive electrode plate of a cycle type sealed lead storage battery, a battery comprising an electrode group using only one separator,
It is also improved for batteries with a high degree of compression of the electrode group. SOLUTION: A band 4 made of an acid-resistant material that does not hold an electrolytic solution is provided between a negative electrode plate 2 and a separator 3 of an electrode group.
The band 4 is disposed such that one end reaches the outer peripheral portion of the negative electrode plate 2 with which the band 4 is in contact. With this configuration, the oxygen gas generated from the positive electrode plate 1 and staying outside the electrode group inside the cell is converted into a band 4 made of an acid-resistant material that does not hold an electrolytic solution.
Can be diffused along the band 4 to the surface of the negative electrode plate 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art In recent years, the use of sealed lead-acid batteries has been increasing in the field of cycle applications in which charge / discharge is repeated, as represented by electric vehicle power supplies, and it is required that quick charge is possible. It is becoming. However, it is generally known that in rapid charging, the amount of oxygen gas generated at the positive electrode at the end of charging exceeds the amount of oxygen absorbed at the negative electrode, and the electrolyte decreases to shorten the cycle life. It is necessary to improve the capability of absorbing oxygen gas.

For example, Japanese Patent Application Laid-Open No. Sho 59-121777 discloses that two or more separators are stacked between a positive electrode plate and a negative electrode plate in order to improve the ability of the negative electrode plate to absorb oxygen gas. FIG. 1 shows a sealed lead-acid battery in which a separator having a slit for diffusing oxygen gas is disposed on a surface in contact with a negative electrode plate.

[0004]

However, the above-mentioned prior art can be applied only to a sealed type lead-acid battery having a configuration in which two or more separators are stacked and used, and the degree of compression of the electrode group is large. The separator also adheres to the negative electrode plate even in the slitted portion, making it impossible to secure a portion in contact with oxygen gas on the negative electrode plate surface, thereby improving the oxygen gas absorbing capacity of the negative electrode plate There is a problem that it may not be possible to do so.

An object of the present invention is to solve the above-mentioned problems, and an object of the present invention is to provide a sealed lead-acid battery excellent in cycle life characteristics which has not been achieved in a cycle application involving quick charging.

[0006]

According to the present invention, there is provided a sealed lead-acid battery for solving the above-mentioned conventional problems, wherein the sealed lead-acid battery is made of an acid-resistant material which does not hold an electrolytic solution between a negative electrode plate and a separator. A band is provided, and the band has an electrode group in which one end or both ends reach the outer peripheral portion of the negative electrode plate. With this configuration, 2
There is versatility that can be adopted not only in a sealed lead-acid battery having a configuration in which two or more separators are stacked, but also in a sealed lead-acid battery having a configuration in which only one separator is used. And even when the degree of compression of the electrode plate group is large, a part of the negative electrode plate is not in close contact with the separator holding the electrolyte, because the band is made of a material that does not hold the electrolyte, Oxygen gas generated from the positive electrode plate when performing rapid charging and staying outside the electrode plate group inside the cell is supplied from one or both ends of the band member arranged to reach the outer peripheral portion of the negative electrode plate. Along the surface of the negative electrode plate, the amount of oxygen gas absorbed from the negative electrode plate can be increased, and the amount of the electrolyte can be maintained. As a result, it is possible to obtain a sealed lead-acid battery having excellent cycle life characteristics in cycle applications involving quick charging.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a sealed lead-acid battery according to the present invention, as described in claim 1, between a negative electrode plate and a separator,
A band made of an acid-resistant material that does not hold an electrolytic solution is provided, and the band has an electrode group in which one end thereof reaches the outer peripheral portion of the negative electrode plate. I keep it. In addition, the shape and position of the band can be set according to the required oxygen gas absorption capacity of the negative electrode plate, but the reaction area of the negative electrode plate is reduced by the arrangement of the band, It should be noted that the discharge capacity of the battery is reduced, and the area of the band must be determined so as not to make the area of the band unnecessarily large.

According to the present invention, the above-mentioned structure allows the band to be used in a battery having an electrode group using only one separator or in a battery having a high degree of compression of the electrode group. By being a material that does not hold the electrolyte, a part of the negative electrode plate does not adhere to the separator that holds the electrolyte, and is generated from the positive electrode plate when performing quick charging and is formed of the electrode group inside the cell. Oxygen gas staying outside can diffuse to the surface of the negative electrode plate along the band from the end of the band arranged to reach the outer peripheral portion of the negative electrode plate, thereby increasing the absorption amount of oxygen gas. As a result, the amount of the electrolyte can be maintained.

Further, the present invention provides,
By disposing the both ends of the band so as to reach the outer peripheral portion of the negative electrode plate, oxygen gas is diffused along the band on the surface of the negative electrode plate more than the invention of claim 1, and the amount of oxygen gas absorbed by the negative electrode Can be increased.

[0010] Further, the present invention provides,
The strips can be implemented in combination such that a plurality of strips are parallel or cross. The number of strips and the arrangement of the strips in combination can be set according to the required oxygen gas absorbing capacity of the negative electrode plate.

[0011] Further, the present invention provides,
The strip can be implemented as a hairpin-shaped structure.

[0012]

Next, an embodiment of the present invention will be described.

In FIG. 1, the electrode plate group is composed of three mat-shaped separators 3 disposed between three positive electrode plates 1 and a negative electrode plate 2. It is made of polyethylene and has a thickness of 0.2mm and a width of 1m
Six strips 4 having a length m and a half of the height of the negative electrode plate 2 are provided, and one end of the strip 4 reaches the upper side of the negative electrode plate 2. The electrode group having the above-described configuration is configured so that the nominal voltage is 12 V,
Battery A was used for a sealed lead-acid battery having a nominal capacity (20 hour rate) of 28 Ah.

As shown in FIG. 2, the strip 5 is disposed so that both ends thereof reach the outer peripheral portions of the upper and lower sides of the negative electrode plate 2, and is constituted by a positive electrode plate 1, a negative electrode plate 2 and a separator 3. The electrode group was adopted as a sealed lead-acid battery similar to the battery A, and a battery B was obtained.

Further, as shown in FIG. 3, in addition to the vertical band 6 whose both ends reach the upper and lower sides of the negative electrode plate 2,
The electrode group composed of a horizontal band 7 having the same width as that of the battery A and the battery B was adopted as a sealed lead-acid battery similar to the batteries A and B.

As shown in FIG. 4, a band 8 bent into a hairpin shape is inserted between the negative electrode plate 2 and the separator 3 as indicated by a black arrow in FIG. The negative electrode plate 2 was disposed so as to reach the upper side. Then, the electrode group having the hairpin-shaped band 8 is referred to as a battery A, a battery B,
Battery D was employed as a sealed lead-acid battery similar to Battery C.

The batteries A, B, C, and D were sealed lead-acid batteries having a separator compression ratio of 1.25 and a high degree of compression of the electrode assembly.

These sealed lead-acid batteries were subjected to a life test in which a cycle of discharging the battery to a final voltage of 10.4 V at 14 A, and charging the battery for 3 hours at a charging voltage of 15.6 V and a maximum current of 14 A was repeated. In addition, a seal provided with an electrode group including only three positive plates, four negative plates, and a mat-shaped separator disposed between the positive and negative plates, instead of the structure of the present invention. FIG. 5 shows the results of changes in capacity and weight loss with the number of cycles using a conventional lead-acid battery as a conventional product E. In the conventional product E, the amount of decrease in capacity and the amount of increase in weight decrease with the progress of the cycle are large. On the other hand, the batteries A and B and the batteries C and D show a small decrease in capacity even when the cycle proceeds. Such a result was obtained because the ability to absorb oxygen gas generated from the positive electrode at the end of charging was improved since the increase in weight loss was smaller than that of the conventional product. Therefore, it was confirmed that the sealed lead-acid battery was able to maintain the amount of the electrolyte and to have excellent cycle life characteristics.

In the group of electrodes of the battery A shown in FIG. 1, the cycle life characteristics when the band 4 is arranged so that both ends do not reach the outer periphery of the negative electrode plate 2 are different from those of the conventional product E. Similar results were obtained. For this reason, in order to obtain the effects of the present invention, it is necessary to arrange the band so that one end or both ends reach the outer peripheral portion of the negative electrode plate. In this embodiment, polyethylene was used as the material of the belt, but the same effect was obtained by using one kind of resin material selected from polypropylene, polyvinyl chloride, and ABS resin.

[0020]

As described above, according to the present invention, a battery comprising an electrode group in which two or more separators are not stacked,
Even for batteries with a large degree of compression of the electrode plate group, the ability of the negative electrode plate to absorb oxygen gas can be reliably improved,
By maintaining the amount of electrolyte in a cycle application accompanied by quick charging, a sealed lead-acid battery having excellent cycle life characteristics can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing an electrode group constituting a battery A in an embodiment of the present invention.

FIG. 2 is a schematic perspective view showing an electrode group constituting a battery B in an embodiment of the present invention.

FIG. 3 is a schematic perspective view showing a group of electrodes constituting a battery C in an example of the present invention.

FIG. 4 is a schematic perspective view showing an electrode group constituting a battery D according to an embodiment of the present invention.

FIG. 5 is a diagram showing the capacity and weight loss of a battery A, a battery B, a battery C, a battery D, and a conventional product E in a cycle life test in Examples.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Positive electrode plate 2 Negative electrode plate 3 Separator 4,5 Strip 6 Vertical strip 7 Horizontal strip 8 Hairpin type strip

Claims (5)

[Claims] 1. An electrode group comprising a positive electrode plate, a negative electrode plate, and a mat-shaped separator interposed between the positive electrode plate and the negative electrode plate, wherein an electrolytic plate is provided between the negative electrode plate and the separator. A sealed lead-acid battery in which a strip made of an acid-resistant material that does not hold a liquid is disposed such that one end reaches the outer peripheral portion of the negative electrode plate. 2. The sealed lead-acid battery according to claim 1, wherein the band is disposed so that both ends thereof reach the outer periphery of the negative electrode plate. 3. The sealed lead-acid battery according to claim 1, wherein a plurality of strips are combined so as to be parallel or intersecting. 4. The sealed lead-acid battery according to claim 1, wherein the band is a hairpin-shaped band bent into a hairpin shape. 5. The sealed lead-acid battery according to claim 1, wherein the belt is made of a resin material selected from the group consisting of polyethylene, polypropylene, polyvinyl chloride and ABS resin.