JPH10134794A - Cylindrical sealed lead-acid battery - Google Patents

Abstract

(57) [Abstract] [Problem] To make electrode spacing of a cylindrical sealed lead-acid battery uniform,
Uniform charge / discharge reaction of the electrode plate to prevent internal short circuit. The distance between the electrode plates is made uniform by gradually reducing the thickness of the separator from the core to the end of the winding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Sealed lead-acid batteries can be roughly classified into two types depending on the shape of the battery. One is a prismatic type which has been widely used as an automobile battery, and the other is a cylindrical type. In the former, a required number of plates are alternately interposed between a plate-like positive electrode plate filled with a lead alloy lattice using lead dioxide as an active material and a negative electrode plate filled with a lead alloy lattice using metallic lead as an active material with a separator interposed. The latter is obtained by winding a cylindrical current collector between a positive electrode plate and a negative electrode plate, each of which is filled with an active material in a belt-like current collector, with a separator interposed therebetween.

[0003] In the latter type of cylindrical lead battery, a battery having excellent rapid discharge characteristics and life performance is produced by winding a thinner electrode plate than a prismatic lead battery in a cylindrical shape at a high group pressure to form an electrode plate group. be able to.

FIG. 1 is a sectional view of a conventional cylindrical sealed lead-acid battery. 1 is a positive electrode plate, 2 is a negative electrode plate, and 3a is a sheet separator.

[0005]

In the conventional cylindrical sealed lead-acid battery constructed as described above, the sheet-like separator 3a had a uniform thickness from the core side to the winding end side. . In this case, the group pressure is higher on the winding core side than on the winding end side, and the separator 3a is more compressed, so that the distance between the electrodes is reduced at that portion, the reaction distribution becomes nonuniform, and a short circuit is likely to occur. Had a problem.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems.
In a cylindrical sealed lead-acid battery in which a liquid retaining separator is interposed between the negative electrode plates and wound in a cylindrical shape and accommodated in a battery case, the thickness of the separator gradually increases from the core to the end of the winding. The second invention is characterized in that the separator has at least two different lengths.
The present invention is characterized in that the separators are overlapped with each other in a state where the separators become gradually thinner from the winding core portion toward the winding end edge, and the central portion of the winding core portion is fixed.

[0007]

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

FIG. 2 shows an embodiment of a separator for a cylindrical sealed lead battery according to the present invention. FIG. 3 is a sectional view of a cylindrical sealed lead-acid battery using the multilayer separator shown in FIG.

The non-woven fabric mainly composed of glass fiber is used as the material for the cylindrical sealed lead-acid battery separator of the present invention, and at least two separators having different lengths are polymerized as shown in FIG. The superposed parts are overlapped from the center line of the parts to the end parts, and a multilayer separator is used, which is fixed on the center line of the superposed part. The thickness and length of each of the sheet separators (indicated by a, b, c, and d in FIG. 2) are determined based on the design of the cylindrical sealed lead-acid battery.

Next, the multi-layer separator is wound into a cylindrical shape using an appropriate jig with the center line of the overlapped portion aligned with the core of the cylindrical sealed lead-acid battery. Third
The figure shows an example of a cylindrical sealed lead-acid battery using the multilayer separator.

A cylindrical sealed lead-acid battery shown in FIG. 1 has a power generating element comprising a positive electrode 1 mainly composed of lead dioxide, a negative electrode 2 mainly composed of metallic lead, and the multi-layer separator 3b. It was done. The positive and negative plates 1 and 2 are formed by applying an active material paste to an expanded grid to facilitate winding, and the entire multi-layer separator 3 is interposed therebetween. did.

As shown in FIG. 2, in the cylindrical lead-acid battery separator having the above-mentioned structure, the thickness of the portion where the sheet-like separators are overlapped becomes thinner from the core to the end of the winding. Has become. For this reason, especially in the core portion, since the number of stacked sheet-like separator pieces is increased, the group pressure is high and the multilayer separator 3b is increased.
Even in a more compressed state, the distance between the positive electrode and the negative electrode is kept optimal, so that the reaction distribution can be made uniform and a local short circuit can be prevented.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on embodiments. A positive / negative electrode plate having a thickness of 300 μm and a length of about 500 mm and two separators having a thickness of 0.5 mm were wound with the center line of the overlapped portion coincident with the core and then sealed in a battery case. . The total length of the two separators is 150 mm for a short piece.
A long piece having a length of 550 mm was used. Injection and formation of an electrolytic solution were performed according to a usual method, and a cylindrical battery of about 2.5 Ah (3 HR) was manufactured. 0.5mm thick and 550mm long for comparison
A conventional battery using a single separator was also manufactured.

These batteries were discharged at a current of 1 CA to 1.7 V each time and subjected to a life test in a pattern of charging about 110% of the discharged amount. FIG. 4 shows the test results, which show that the battery of the present invention has a significantly longer life than the conventional battery.

In this embodiment, the thickness of the separator is changed step by step by attaching the separator. However, in the manufacturing process of the separator, the thickness of the separator is changed by continuously changing the papermaking speed. The same effect can be obtained by continuously changing and using a separator.

[0016]

As described above, in the cylindrical lead-acid battery according to the present invention, since the interval between the electrode plates can be kept constant, the charge / discharge reaction is uniform in each part of the electrode plate and the local It has an excellent effect of preventing a typical internal short circuit.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a conventional cylindrical sealed lead-acid battery.

FIG. 2 is a perspective view showing an embodiment of a multilayer separator.

FIG. 3 is a sectional view showing an embodiment of a sealed cylindrical lead-acid battery according to the present invention.

FIG. 4 is a diagram showing the results of life tests of an example according to the present invention and a conventional example.

[Explanation of symbols]

 1. 1. positive electrode plate Negative electrode plate 3a. Separator 3b. Multi-layer separator

Claims (2)

[Claims] 1. A cylindrical sealed lead-acid battery in which a liquid-retaining separator is interposed between positive and negative electrode strips and wound in a cylindrical shape and accommodated in a battery case, the thickness of said separator is determined by a core portion. A sealed cylindrical lead-acid battery characterized in that the thickness of the lead-acid battery is gradually reduced toward the end of the winding. 2. The method according to claim 1, wherein at least two separators having different lengths are overlapped with each other in a state where the separators are gradually thinned from the core portion toward the winding end edge, and the core portions are fastened. A cylindrical sealed lead-acid battery as described.