JP2001273918A - Manufacturing method of cylindrical sealed lead-acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sure manufacturing method of a cylindrical sealed lead- acid battery which has an improved battery life. SOLUTION: To each of grid substrate 1 of multiple sheets, which are continuously cast by a continuous casting system, multiple sheets of positive electrode plate P that has been manufactured by filling up a positive electrode active material 8 are manufactured, and when each positive electrode plate P is laminated and wound together with the negative electrode plate N via a retainer mat separator S, a slope 2a of outer frame 2 of the grid substrate 1 and slopes 3a, 3a, 4a, 4a of length and breadth side lattice bars 3, 4 are laminated and wound toward the inside to assemble a wound electrode plate group W, and respective wound electrode plate group W is housed in a cylindrical container, and capped airtightly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a cylindrical sealed lead-acid battery used for starting an engine of an automobile, for assisting discharge from a battery during acceleration, and for HEV for performing regenerative charging at a high rate current during deceleration.

[0002]

2. Description of the Related Art In order to manufacture a conventional cylindrical sealed lead-acid battery, first, a large number of lattice substrates are cast by continuous casting using a well-known continuous casting apparatus. For example, using a large number of grid substrates continuously cast by a continuous casting apparatus A equipped with a rotary drum mold A1 shown in FIG. 4, each of which is successively filled with a positive electrode active material to produce a large number of positive plates After that, each positive electrode plate is laminated with a negative electrode plate via a retainer mat separator to assemble a large number of wound electrode plates, and then each of the wound electrode plates is accommodated in a cylindrical container, and a predetermined amount The diluted sulfuric acid electrolyte is injected, and a lid provided with a safety valve is usually hermetically sealed in the cylindrical container.

[0003]

However, among a large number of cylindrical sealed lead-acid batteries manufactured using a grid substrate continuously cast by the above-mentioned continuous casting method, some batteries have a relatively long battery life. Although long, some batteries have a relatively short battery life, with the inconvenience of having large variations in battery life as a whole. The inventor of the present invention has conducted tests and studies in order to pursue the cause of a short battery life and a large variation in the battery life as a whole. Is
The cross-sectional shapes of the lattice frame and the vertical and horizontal lattice bars are trapezoidal, and their respective side surfaces are formed as inclined surfaces corresponding to draft angles formed in the molding grooves of the rotary drum mold. When laminating and winding an electrode plate manufactured using such a lattice substrate,
Without considering the direction of such a cross-sectional shape of the lattice substrate,
Since a large number of batteries were manufactured by incorporating a wound electrode group assembled by lamination and winding into a cylindrical container, it was found that the above-mentioned inconvenience occurred. The present invention is based on this finding, manufactures an electrode plate manufactured using a grid substrate that is continuously cast by a continuous casting method, and assembles a wound electrode plate group using the same, and the wound electrode plate group When a large number of cylindrical sealed lead-acid batteries are manufactured using the above, the problem of the above-mentioned conventional technology is solved, the battery life of each manufactured battery is long, and the batteries manufactured in large numbers are all long-lived, In addition, it was possible to develop a manufacturing method capable of reducing the variation in the battery life of all the manufactured batteries.

[0004]

Means for Solving the Problems After producing a large number of positive plates using a grid substrate continuously cast by a continuous casting apparatus equipped with a rotary drum mold, each of the positive plates is connected to a negative electrode through a retainer mat separator. In assembling a plate and a large number of laminated and wound electrode plates, each positive electrode plate was formed in a forming groove of a rotating drum mold formed in a trapezoidal lattice frame and a lattice bar of a trapezoidal cross section of the lattice substrate. Assemble only a wound electrode plate group formed by laminating and winding the inclined surface corresponding to the draft angle toward the inside, storing each wound electrode plate group in a cylindrical container, injecting liquid, covering with lid and sealing. Manufacturing method of cylindrical lead-acid battery.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail. As is well known, the continuous casting apparatus A illustrated in FIG.
The outer periphery of the rotary drum mold A1 formed by continuously engraving a rotary drum mold A1, a cooling shoe A2 abutting on an inner circumferential surface thereof in an arc shape, and a plurality of substrate lattice forming grooves on the entire circumferential surface. Nozzle array A3 that is arranged in the width direction to be injected into the molding groove on the surface
While rotating the rotary drum mold A1 in the direction of the arrow, while injecting lead molten metal into the lattice forming groove from the nozzle row,
By passing through the shoe A2, a large number of lattice substrates are continuously obtained in a belt shape, pulled in the direction of the arrow via the guide rail A4, and then cut at the connecting portion of each adjacent lattice substrate. Is manufactured. An active material is filled by using a large number of sheets manufactured in this way, and a large number of positive electrode plates or negative electrode plates are manufactured. For example, when manufacturing a positive electrode plate, each grid substrate is filled with a positive electrode active material, and then a large number of positive electrode plates having a uniform thickness are manufactured by pressing.

The U-shaped grooves for forming the outer frame of the lattice substrate and the U-shaped grooves for forming the vertical and horizontal lattices, which are formed on the peripheral surface of the rotary drum mold A1, are not shown, but are well known. It is cut into a substrate having a draft so that the grid substrate continuously cast can be easily released from the mold. Therefore, as shown in FIG. 1, each lattice substrate released from the mold is separated from the inner peripheral side surface 2a of the surrounding frame 2 and both side surfaces 3a, 3a and 4a, 4a of the vertical and horizontal lattice bars 3, 4. The cross-sectional shape of the surrounding frame 2 and the vertical and horizontal lattice bars 3 and 4 is trapezoidal. In other words, the inner surface 2a of the enclosure 2
The width of the vertical lattice bar 3 and the width of the horizontal lattice bar 4 gradually increase from one end face to the other end face in each thickness direction, and the width dimension of the one end face is different from the width dimension of the other end face in a trapezoidal shape. Therefore, each of the holes 5 for filling the active material, which are formed by the surrounding frame 2 and the vertical and horizontal lattice bars 3 and 4, are formed on the inclined surfaces 2a
In the thickness direction surrounded by 3a and 4a, a trapezoidal shape having a diameter gradually different from one end face to the other end face in the thickness direction is obtained.

In this case, the lattice substrate 1 can be cast by a rotary drum mold in which the depth of the forming groove of the surrounding frame is slightly deeper than the groove of the inner frame. As shown in FIG. 1, the lattice substrate 1 has a vertical and horizontal lattice bars 3, 4 having a trapezoidal cross section.
Are formed on a flat surface 6 located on the same plane as the wide end surface of the enclosing frame 2 having a trapezoidal cross section, and the other surface is formed by the vertical and horizontal lattice bars 3, 4,. The higher height of the surrounding frame 2 forms a concave surface having an active material filling concave surface 7 outside the large-diameter side opening of the large number of active material filling holes 5, 5,... From the concave surface 7 side. Is formed so that the active material can be smoothly and satisfactorily filled.

The positive electrode active material is equally filled in a large number of cast lattice substrates continuously cast as described above, and the thickness is adjusted by pressing. Manufacture a large number of positive electrode plates for winding of length and width, using each positive electrode plate, together with a negative electrode plate for winding via a retainer mat,
Laminated winding using a winding core to assemble a large number of wound electrode plates,
Each of the wound electrode plates is accommodated in each cylindrical container, a predetermined amount of electrolyte is injected, and a lid with or without a safety valve is hermetically sealed by heat sealing or caulking to produce a large number of sealed lead-acid batteries. However, in the past, when assembling an electrode group by stacking and winding positive electrode plates, there is no interest in the fact that the cross-sectional shapes of the above-described lattice substrate used for manufacturing the positive electrode plate and the vertical and horizontal lattice bars are trapezoidal and have directivity. Therefore, the inclined surfaces 2a, 3a,
4a facing inward and, in some cases, its slopes 2a,
3a and 4a were laminated and wound outward to produce a group of wound electrode plates in which the orientation direction of the grid substrate of the positive electrode plate was varied.

In the present invention, each grid substrate 1 is filled and coated with a positive electrode active material 8 by a conventional method, and a number of positive plates are manufactured by regulating the pressure, and each of the positive plates is laminated with a negative plate through a retainer mat separator. When turning, as shown in FIG. 2, the inclined surface 2a of the frame 2 of the lattice substrate 1 and the vertical lattice
And the negative electrode plate N via the retainer mat separator S in a state where the inclined surfaces 3a, 3a on both sides of the horizontal grid bar 4 and the inclined surfaces 4a, 4a on both sides of the horizontal lattice bar 4 are oriented inward. Assemble. The cylindrical lead-acid battery manufactured by incorporating the assembled rolled electrode group into a cylindrical container has the following characteristics.
The expansion of the positive electrode active material 8 filled in
Inwardly inclined surface 2a and the inwardly inclined surface 3a, 3 surrounding each of a pair of opposed vertical and horizontal lattice bars 3, 3, 4, 4.
a, 4a, 4a act in a direction to suppress the expansion of the positive electrode active material, and at the same time, each active material filling hole 5
Has a small diameter toward the outside thereof, so that the expanding positive electrode active material is favorably maintained in the active material filling hole 5 and is pressed against these four circumferentially inclined surfaces of the lattice substrate 1 so as to be excellent. Since the adhesiveness is maintained, a battery having a relatively long battery life is obtained. Furthermore, the variation in the life of a large number of batteries manufactured in this manner is reduced, and only a good battery is obtained.

On the other hand, when the positive electrode plate P is laminated and wound, as shown in FIG. 3, the inclined surface 2a of the surrounding frame 2 of the lattice substrate 1 and the inclined surfaces 3a, 3a on both sides of the vertical lattice bar 3 as shown in FIG. The cylindrical lead-acid battery manufactured by using the negative electrode plate N laminated and wound to assemble the wound electrode plate group W 'with the inclined surfaces 4a, 4a on both sides of the horizontal lattice bar 4 facing outward is charged. When the discharge is used repeatedly, the expansion of the positive electrode active material 8 filled in each active material filling hole 5 causes the inclined surface 2a of each surrounding frame 2 and a pair of vertical and horizontal lattice bars 3 facing each other. , 3,4
Since the surrounding inclined surfaces 3a, 3a, 4a, 4a of 4 are all directed outward, not only is there no effect of suppressing the expanding active material, but also each of the active material filling holes 5 is located on the outside thereof. Since the active material expands in the opposite direction, the expanding active material swells outward from the inside of the active material filling hole 5 and the adhesiveness of the lattice substrate 1 to these inclined surfaces is reduced. The life of many batteries manufactured in this manner.

Based on such findings of the inventor, the present invention provides:
When the positive electrode plate P is laminated and wound, as shown in FIG.
The inclined surface 2a of the outer frame 2 of the lattice substrate 1 and the vertical and inclined surfaces 3a, 3a, 4a, 4a of the horizontal lattice bars 3, 4 are oriented inward, that is, the thick end surface and the vertical In a state where the thicker end faces of the horizontal lattice bars 3 and 4 are oriented outward, they are laminated and wound to assemble a wound electrode plate group W, and each of the wound electrode plate groups W
Is stored in each cylindrical metal container according to a conventional method, a predetermined amount of each sulfuric acid electrolytic solution is injected, the wound electrode group is impregnated, and a metal lid provided with a safety valve on an upper peripheral edge of the cylindrical metal container is swaged. Then, each of the sealed cylindrical lead-acid batteries was manufactured. When a charge / discharge cycle test was performed on all of the batteries manufactured in this manner, the battery life was long and there was almost no variation in the number of charge / discharge cycles. On the other hand, using the wound electrode plate group W 'shown in FIG. 3, each cylindrical sealed lead-acid battery was manufactured in the same manner as described above according to a conventional method, and all the batteries were similarly charged. As a result of a discharge cycle test, the life of all batteries was short, and a large variation was found in the number of charge / discharge cycles of each battery.

When assembling the wound electrode plate groups W and W 'of FIGS. 2 and 3, the grid substrate of the negative electrode plate N laminated on the positive electrode plate P was continuously cast using the above-described continuous casting apparatus. Each of the lattice substrates 1 is filled with a negative electrode active material 9 to produce a large number of negative plates N, and these are laminated and wound with a positive electrode plate P via a retainer mat separator S. Sometimes, unlike the positive electrode active material, it does not expand, so the orientation of the lattice substrate 1 may be in any direction,
As shown in FIG. 2, the inclined surface 2a of the outer frame grid 2 is
Inclined surfaces 3a, 3a and 4a on both sides of the horizontal lattice bars 3 and 4;
Preferably, 4a is laminated and wound in an inwardly oriented state. The one shown in FIG.
In this example, the inclined surface 2a of the outer frame lattice 2 and the inclined surfaces 3a, 3a and 4a, 4a on both sides of the vertical and horizontal lattice bars 3, 4 are laminated and wound in an outwardly oriented state. 2 and 3
In the figure, reference numeral 10 denotes a filling paper. When filling the grid substrate 1 with the active material, the filling paper 10 is attached to the flat surface side 6 with its concave side 7 facing upward and the downward facing flat surface side 6 beforehand so that each of the active material filling holes 5, 5 is attached. ,... Can be filled with the active material from the concave side 7 above it.

Next, more specific examples will be described together with comparative examples. Example Pb-1.0 wt. 0.8 mm in thickness, 140 mm in length and 11 in width composed of a lead alloy composition of% Sn
A number of grid substrates for winding shown in FIG. 1 having a thickness of 0 mm were produced. On the other hand, a paste having a density of 3.6 g / cc was prepared by kneading lead powder of 70% PbO, lead red, sulfuric acid, water and PVA, and further, 0.04 wt. % Is added and kneaded to form a paste-like positive electrode active material, while 0.4 wt. %, Acetylene black 0.2 wt. %, Barium sulfate 2 wt.
%, Organic short fiber 0.04 wt. % Is added and kneaded to prepare a paste-like negative electrode active material, and the positive electrode active material is placed on each of the lattice substrates with the concave surface 7 facing upward and the flat surface 6 facing downward with a thickness of 0.1 mm. Filled and coated from the concave side 7 with the liquid-absorbent filling paper made of a 2 mm retainer mat attached, and then adjusted to a thickness of about 0.9 mm through a pressure roller to form a large number of positive plates. Was manufactured. Further, the paste-like negative electrode active material was applied to each of the lattice substrates by a thickness of 0.2 mm in the same manner as in the production of the positive electrode plate.
And a filling paper made of a retainer mat of No. 7 is applied, and the filling paper is applied from the concave side 7 thereof, and is passed through a pressure roller to a thickness of about 0.
A large number of negative electrode plates were manufactured by adjusting the thickness to 9 mm. Next, using the above positive electrode plate and negative electrode plate, a 0.8 mm thick retainer mat separator S was used between the positive and negative electrode plates.
As shown in FIG. 2, each of the grid substrates 1 of the positive electrode plate P and the negative electrode plate N
a, 3a, 4a are oriented inward, in other words, in a state where the trapezoidal enclosing frame 2 and the wide end faces of the vertical and horizontal lattice bars 3, 4 are oriented outward, and are laminated and wound according to the present invention. A large number of the wound electrode plate groups W were assembled.

For comparison, these positive electrode plates P
And a negative plate N, and a thickness of 1.0 mm between the positive and negative plates.
As shown in FIG. 3, the respective lattice substrates 1 of the positive electrode plate P and the negative electrode plate N have their inclined surfaces 2a, 3a, and 4a facing outward, as shown in FIG. Then, the trapezoidal enclosing frame 2 and the wide end faces of the vertical and horizontal lattice bars 3 and 4 are laminated and wound in a state where the wide end faces are oriented outward, and a large number of wound electrode groups W 'for comparison are assembled. . Next, each of the thus assembled rolled electrode group W of the present invention and each of the wound electrode group W 'for comparison are placed in a cylindrical container made of synthetic resin, and have a specific gravity of about 1 including sodium sulfate. .
The diluted sulfuric acid of No. 24 was injected, discharge was performed at 1.4 A, and charged at 180% of the theoretical capacity. After charging, rehydration was performed to adjust the specific gravity to 1.30, and to a predetermined volume, the current collector and the terminal were welded, a lid provided with a rubber valve was attached, and the terminal, the lid, and the lid and the container were replaced. The cylindrical lead-acid battery of the present invention of 2 V and 4 Ah sealed with epoxy resin and the cylindrical lead-acid battery for comparison are each 1
0 pieces were manufactured at a time.

Next, with respect to each of the batteries of the present invention and the comparative batteries manufactured in this manner, the test was performed at 0.25 C (1 A) for 2.4 hours, and the test was performed at 2 A (0.5 C) /2.45 V /
The two-stage constant current charging was performed for 5.6 hours under the condition of 0.2 A, and
The charge / discharge was performed at a cycle of 8 hours. The capacity was checked every 50 cycles, and the time when the capacity was reduced to 80% of the initial capacity was defined as the life. As a result, the number of charge / discharge cycles until the life of the present invention is 301 for the shortest and 356 for the longest.
Times, the average number of charge / discharge cycles of 10 batteries was 330 times. On the other hand, the number of charge / discharge cycles of the comparative battery was 224 for the shortest battery and 285 for the longest battery.
The average number of charge / discharge cycles of 0 batteries was 255 times. As described above, all the batteries including the wound electrode plate group of the present invention were superior in the battery life to all the comparative batteries.

[0016]

As described above, according to the present invention, a large number of positive plates are manufactured using a lattice substrate cast by a continuous casting method, and each of the positive plates is laminated with a negative plate through a retainer mat separator. At the time of winding, the wound electrode plate group is assembled by laminating and winding so that the inclined surface of the frame of the lattice substrate and the inclined surface of the vertical and horizontal lattices face inward. Since the cylindrical sealed lead-acid battery is manufactured using only the group, a large number of batteries having a long battery life and no variation can always be manufactured reliably.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a lattice substrate cast by a continuous casting device.

FIG. 2 is a cross-sectional view of a part of the wound electrode group of the present invention.

FIG. 3 is a cross-sectional view of a part of a comparatively wound electrode plate group.

FIG. 4 is a perspective view of an example of a continuous casting apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Continuous casting lattice substrate 2 Surrounding frame 2a Inclined surface 3 Vertical lattice bar 3a Inclined surface 4 Horizontal lattice bar 4a Inclined surface 5 Active material filling hole 6 Flat surface side of lattice substrate 7 Concave surface side of lattice substrate 8 Positive electrode active material 9 Negative electrode active material Substance S Retainer mat separator P Positive electrode plate N Negative electrode plate W Wound electrode plate group of the present invention

Claims (1)

[Claims] 1. After manufacturing a large number of positive plates using a grid substrate continuously cast by a continuous casting apparatus equipped with a rotary drum mold, each positive plate is laminated with a negative plate through a retainer mat separator. In assembling a large number of the wound and wound electrode plates, each positive electrode plate corresponds to a draft angle formed in a forming groove of a rotary drum mold formed in a lattice frame having a trapezoidal cross section of the lattice substrate and a lattice bar, respectively. Assemble only a rolled electrode group formed by laminating and winding with the inclined surface facing inward, storing each wound electrode group in a cylindrical container, injecting,
A method of manufacturing a cylindrical sealed lead-acid battery with a closed lid.