JP2001085017A - Lead-acid battery and lattice for it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lattice for a lead-acid battery having stabilized quality despite a fast production speed and an approximately uniform lifetime. SOLUTION: The lattice for a lead-acid battery has a tab 1A, and near its root, an upper frame rib 1B is provided with an elliptical recess 1D having a tapered surface of 90% deep-(A). The recess 1D is cast using a cylindrical drum as a die, whereby an elliptical projection is formed on the drum surface in such a way as mating with the recess 1D-(B). As the heat capacity of the tab root part lessens to quicken solidification of molten lead, there is no risk that the molten lead is scraped off at random from the tab root in an unsolidified state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grid for a lead storage battery and a lead storage battery, and more particularly to a grid for a lead storage battery manufactured by a continuous casting method and a lead storage battery provided with the grid.

[0002]

2. Description of the Related Art Conventionally, a grid for a lead-acid battery is obtained by pouring molten lead having a predetermined composition into a mold, solidifying the solid, removing the solidified body from the mold, and cutting and removing unnecessary gate portions. It was manufactured by the book mold method. However, in the book mold method, the thickness and weight of the lattice body vary, and a problem arises in terms of productivity because batch processing is performed collectively to cut unnecessary gate portions. A continuous casting method is employed for manufacturing the lattice.

In this continuous casting method, for example, the surface of a cylindrical drum or the like is used as a lattice mold, and molten lead is continuously ejected from a nozzle in contact with the drum while rotating the drum. A solidified continuous grid is drawn in the tangential direction of the drum to obtain a grid.

[0004]

However, in a grid manufactured by a continuous casting method, molten lead is injected into a mold, solidified within a certain period of time, and is scraped off by a scraping plate. In addition, there is a problem that the upper frame bone near the ear root having a large heat capacity of the lattice body is worn off in an unsolidified state, and the upper frame bone is randomly cut into a concave shape, and the quality of the lattice body is not stable. .

[0005] In a lead-acid battery, the oxidation-reduction reaction is repeated by the charge / discharge cycle and the corrosion of the lattice body progresses.
As shown in FIG. 5, when the upper frame bone 1B near the base of the ear 1A is randomly cut into a concave shape, the life of the lead storage battery is greatly affected. In addition, since a considerable number of grids are used in series in a lead-acid battery, if one grid reaches the end of its life, the entire lead-acid battery will end its life.

The present invention has been made in view of the above circumstances, and has as its object to provide a grid for a lead storage battery which has stable quality even when the production speed is increased and has a substantially uniform life, and a lead storage battery provided with the grid. .

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a grid for a lead-acid battery manufactured by a continuous casting method, which promotes solidification of the grid at the base of an ear of the grid. The solidification promoting portion is formed. In the present invention, since the coagulation accelerating portion for accelerating the solidification of the lattice body is formed in the ear root part of the lattice body, the heat capacity of the ear root part is reduced, and the solidification of the molten lead is accelerated. For this reason, the molten lead is not randomly scraped off from the uncoagulated ear root portion, and a stable lattice body can be obtained.

In this case, it is preferable that the coagulation accelerating portion is a concave portion formed in the ear root portion or a downwardly opened slit formed in the upper frame bone of the ear root portion. In a lead-acid battery provided with such a grid for a lead-acid battery, since the quality of the grid for a lead-acid battery is stable and the life of the grid is substantially equal, the life of a specific grid becomes the lead-acid battery. It is possible to prevent the overall life from being shortened.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment of a lead storage battery to which the present invention is applied will be described below with reference to the drawings.

[0010] Pure lead (Pb) is heated, antimony (Sb) is added thereto and stirred, and Pb: Sb = 98.5: 1.
The molten lead having the composition of No. 5 was produced, and molten lead was injected from a nozzle to a cylindrical drum by a continuous casting method to produce a lattice body.

As shown in FIG. 1, in a lattice body 1 manufactured by a continuous casting method, a lattice 1C is arranged in a lattice shape on a frame bone including an upper frame bone 1B, and an ear 1A extends from the upper frame bone 1B. Extend upward. As shown in FIG.
The upper frame bone 1B near the base of the ear 1A is formed with an elliptical concave portion 1D having a tapered surface with a depth of 90%. FIG.
As shown in (B), the concave portion 1D is formed by forming an elliptical convex portion corresponding to the concave portion 1D on the surface of the cylindrical drum using a cylindrical drum as a mold.

Next, lead powder, 13% by weight of dilute sulfuric acid (specific gravity 1.26: 20 ° C.) based on lead powder, and 1% based on lead powder
2% by weight of water is kneaded to prepare a positive electrode active material paste, and 85 g of the positive electrode active material paste is filled in the lattice 1, and then left in an atmosphere at a temperature of 50 ° C. and a humidity of 95% for 18 hours. After aging, it was allowed to stand at a temperature of 110 ° C. for 2 hours and dried to produce an unformed positive electrode plate 10 (see FIG. 1).

On the other hand, lead powder, 13% by weight of dilute sulfuric acid (specific gravity 1.26: 20 ° C.) with respect to lead powder, and 1% with respect to lead powder
2% by weight of water is kneaded to prepare a negative electrode active material paste, and 73 g of the negative electrode active material paste is filled in the grid 1, and then left in an atmosphere at a temperature of 50 ° C. and a humidity of 95% for 18 hours. After aging, it was left to dry at a temperature of 110 ° C. for 2 hours to produce an unformed negative electrode plate 10 ′.

Next, seven unformed positive electrode plates 10 and eight unformed negative electrode plates 10 ′ are laminated via a separator made of a porous polyethylene film to form each electrode plate group. Was placed in a battery case, and then an electrolytic solution was injected into the battery case to produce an unformed battery. This unformed battery was formed at 9 A for 42 hours to complete a lead storage battery. Note that dilute sulfuric acid having a specific gravity of 1.225 (20 ° C.) was used as the electrolytic solution.

(Second Embodiment) Next, a second embodiment of the lead storage battery to which the present invention is applied will be described. In the following embodiments, the same portions as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. Only different portions will be described.

As shown in FIG. 3A, the lattice body 1 of this embodiment has a depth of 9 mm in the upper frame bone 1B near the base of the ear 1A.
An oval concave portion 1E having a 0% tapered surface is formed. As shown in FIG. 3 (B), the concave portion 1E is obtained by forming a cylindrical drum as a mold and forming an elongated arc-shaped convex portion corresponding to the concave portion 1E on the surface of the cylindrical drum.

(Third Embodiment) Next, a third embodiment of the lead storage battery to which the present invention is applied will be described.

As shown in FIG. 4A, the lattice body 1 of the present embodiment has a depth 1 at the upper frame bone 1B near the base of the ear 1A.
An elongated arc-shaped slit 1F having a tapered surface of 00% and opening downward is formed. As shown in FIG. 4 (B), the slit 1F is obtained by forming a cylindrical drum as a mold and forming an elongated arc-shaped convex portion corresponding to the slit 1F on the surface of the cylindrical drum.

(Test) [Content of Test] According to the above embodiment, 300 lattices 1 were cast at the same speed, respectively (hereinafter, first to third).
The lattices of the embodiment are referred to as lattices of Examples 1 to 3, respectively. ). In addition, in order to confirm the effects of these examples, 300 pieces of the conventional lattice shown in FIG. 5 were cast as comparative examples. For the lattice bodies of these examples and comparative examples, an appearance test was conducted by visual inspection to determine whether the upper frame bone 1B near the base of the ear 1A was randomly cut into a concave shape. The test results of the appearance test are shown in Table 1 below.

[0020]

[Table 1]

[Evaluation] As shown in Table 1, the lattices of Examples 1 to 3 in which a concave portion or a slit was formed near the base of the ear 1A did not have a randomly formed concave portion.
All of the pieces did not have poor appearance. On the other hand, 47 lattices (15.6%) had poor appearance in the lattice of the comparative example.

Therefore, by forming a recess or a slit in the upper frame bone 1B near the base of the ear 1A as in the above-described embodiment, even if the production speed is increased, the portion where the heat capacity of the lattice body 1 is large remains unsolidified. The quality of the lattice body can be kept constant without the upper frame bone 1B being worn away and being randomly shaved into a concave shape. For this reason, it is possible to manufacture a lead storage battery grid body having a uniform life, and a lead storage battery using such a grid body has a shortened life of the entire lead storage battery due to the life of a specific grid body. Can be prevented. In the above embodiment, since the concave portions 1E and 1D and the slit 1F are provided with the tapered surfaces, the heat radiation area is increased and the solidification of the molten lead can be promoted.

[0023]

As described above, according to the present invention,
Since the coagulation promoting portion for promoting the coagulation of the lattice body is formed at the ear root portion of the lattice body, the heat capacity of the ear root portion is reduced, and the solidification of the molten lead is accelerated. The effect that a stable lattice body can be obtained without the molten lead being randomly worn away from the portion can be obtained.

[Brief description of the drawings]

FIG. 1 is a partially broken side view showing an unformed electrode plate of a lead-acid battery according to a first embodiment of the present invention.

FIG. 2A is an enlarged view of the vicinity of a base of an ear of the lattice body of the first embodiment, and FIG. 2B is a cross-sectional view of a cylindrical drum corresponding to a cross section taken along line BB of FIG.

FIG. 3A is an enlarged view of the vicinity of a base of an ear of a lattice body according to a second embodiment, and FIG. 3B is a cross-sectional view of a cylindrical drum corresponding to a cross section taken along line BB of FIG.

FIG. 4A is an enlarged view of the vicinity of a base of an ear of a lattice body according to a third embodiment, and FIG. 4B is a cross-sectional view of a cylindrical drum corresponding to a cross section taken along line BB of FIG.

FIG. 5 (A) is an enlarged view of the vicinity of an ear root of a conventional lattice body, and FIG. 5 (B) is a cross-sectional view of a cylindrical drum corresponding to a cross section taken along line BB of FIG.

[Explanation of symbols]

 1 lattice body 1A ear 1B upper frame bone 1D, 1E recess (coagulation accelerating part) 1F slit (coagulation accelerating part)

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoshiaki Machiyama 2-8-7 Nihonbashi Honcho, Chuo-ku, Tokyo F-term in Shin-Kobe Electric Co., Ltd. (reference) 5H011 AA09 5H016 CC06 EE01 HH15 5H017 AA01 CC05 CC11 DD01 DD08 EE02 HH05

Claims (4)

[Claims] 1. A lead-acid battery grid body manufactured by a continuous casting method, wherein a solidification promoting portion for promoting solidification of the grid body is formed at an ear base of the grid body. Lattice body. 2. The grid for a lead storage battery according to claim 1, wherein the coagulation accelerating portion is a concave portion formed in the ear base portion. 3. The grid body for a lead-acid battery according to claim 1, wherein the coagulation accelerating portion is a downwardly opened slit formed in an upper frame bone of the ear root portion. 4. A lead-acid battery provided with the lead-acid battery grid according to claim 1.