JP2002216836A - Lead storage battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lead storage battery with which an occurrence of short- circuit caused by a stretch grown on an electrode plate touching a strap of the counterpart plate can be prevented. SOLUTION: A group of electrodes of which at least either positive electrode plates or negative electrode plates are housed in a sack-shaped separator is put in a battery container. The upper part of the sack-shaped separator 2 is sealed at least at a part corresponding to an ear section 5a of the counterpart electrode plate or in the vicinity with a seal section 2b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead storage battery in which at least one of a positive electrode plate and a negative electrode plate is accommodated in a bag-like separator.

[0002]

2. Description of the Prior Art FIG. 4 shows that at least one of a positive electrode plate and a negative electrode plate 1 used in a conventional lead-acid battery is accommodated in a bag-like separator 2. In this case, the bag-shaped separator 2 is formed by folding a porous synthetic resin sheet through which the electrolyte passes, and the folded portion 2a is used as a bottom, and both sides are sealed with seals 2b. The structure accommodates the plate 1. The electrode plate 1 accommodated in the bag-shaped separator 2 and an electrode plate (not shown) having a polarity opposite to that of the electrode plate 1
Are alternately stacked to form the electrode group 3. The poles 1 of the same polarity have their ears 1 a connected to each other by a strap 4. Similarly, the poles (not shown) have their ears 5 a connected to each other by straps 6. The electrode group 3 is housed in a battery case together with an electrolytic solution (not shown), and constitutes a lead storage battery.

[0003]

However, in the lead-acid battery having such a structure, the electrode plate 1 is deformed by repeated charging and discharging, and an elongated portion 1b is generated as shown in FIG. In some cases, the strap 6 may contact the strap 6 and short-circuit.

An object of the present invention is to provide a lead-acid battery which can prevent an occurrence of an accident in which an elongated portion is formed on an electrode plate and short-circuited by contact with a strap of a partner electrode.

Another object of the present invention is to provide a lead-acid battery which can prevent the occurrence of an accident in which an elongated portion is formed on the electrode plate and short-circuited due to contact with the strap of the other electrode, and which does not impair the diffusion of the electrolyte. To provide.

[0006]

SUMMARY OF THE INVENTION The present invention is to improve a lead storage battery in which at least one of a positive electrode plate and a negative electrode plate is accommodated in a bag-like separator and an electrode plate group is accommodated in a battery case. It is in.

The lead storage battery according to the present invention is characterized in that the upper portion of the bag-shaped separator is sealed at least at a portion corresponding to the lug portion of the counter electrode plate and in the vicinity thereof.

[0008] When at least the portion corresponding to the ear portion of the counter electrode and the vicinity thereof are sealed at the upper part of the bag-like separator, an extension is generated in the electrode plate and the short-circuit occurs due to contact with the strap of the counter electrode. Can be prevented from occurring.

Further, if the side portion of the bag-shaped separator is sealed while leaving a part thereof, the diffusion of the electrolyte is not impaired.

[0010]

FIG. 1 shows a first embodiment of an electrode group 3 used in a lead storage battery according to the present invention. Parts corresponding to those in FIG. 4 described above are denoted by the same reference numerals.

In the lead storage battery of this embodiment, the upper portion of the porous bag-shaped separator 2 made of synthetic resin has at least a portion corresponding to the lug portion 5a of the counter electrode plate and a seal portion 2 near the portion.
It is sealed with b. Other configurations are the same as those in FIG.

When at least the portion corresponding to the lug portion 5a of the counter electrode plate and its vicinity in the upper portion of the bag-shaped separator 2 are sealed with the seal portion 2b, the occurrence of an extension in the electrode plate 1 is prevented. The short circuit is prevented by the portion 2b, so that it is possible to prevent the occurrence of an accident in which a short circuit occurs due to contact with the strap 6 of the partner electrode.

FIG. 2 shows a second embodiment of the electrode group 3 used in the lead storage battery according to the present invention. Note that parts corresponding to those in FIG. 1 described above are denoted by the same reference numerals.

In the lead storage battery of this embodiment, the upper portion of the porous bag-shaped separator 2 made of synthetic resin has at least a portion corresponding to the lug portion 5a of the counter electrode plate and a seal portion 2 in the vicinity thereof.
It is sealed with b. The side portion of the bag-like separator 2 is sealed with a seal portion 2b except for a part of the bag-like separator 2 which is closer to the lower side as an opening 7. Other configurations are the same as those in FIG.

According to the bag-like separator 2 having such a configuration, the tendency that the diffusion of the electrolyte is impaired by the seal portion 2b can be improved by flowing the electrolyte through the opening 7.

[0016]

The difference in performance between the embodiment of the present invention and the comparative example will be described.

(Comparative Example) A lead storage battery of a comparative example was manufactured as follows. First, a negative electrode plate was made as follows. First, a lattice body having an alloy composition of Pb-0.05% Ca-1.1% Sn was prepared. Next, a lead powder, 13% by mass of dilute sulfuric acid (specific gravity 1.26: 20 ° C.) with respect to the lead powder, and 12% by mass of water with respect to the lead powder are kneaded to prepare a negative electrode active material paste. Was. After 73.0 g of this negative electrode active material paste was filled in a lattice, it was left for 18 hours at a temperature of 50 ° C. and a humidity of 95% for aging, then left at a temperature of 25 ° C. and a humidity of 40% for 2 hours, and dried. To produce an unformed negative electrode plate.

Next, a positive electrode plate was prepared as follows. First, a lattice body having an alloy composition of Pb-0.05% Ca-1.1% Sn was prepared. Next, lead powder, 13% by mass of dilute sulfuric acid (specific gravity 1.26: 20 ° C.) with respect to the lead
The positive electrode active material paste was prepared by kneading with water of mass%.
After filling the grid with 85.5 g of this positive electrode active material paste, the mixture was left to stand at 50 ° C. and 95% humidity for 18 hours for aging, then left at 25 ° C. and 40% humidity for 2 hours and dried. To produce an unformed positive electrode plate.

Next, the unformed positive electrode plates were inserted into the respective polyethylene bag-shaped separators. Each of the non-formed positive electrode plates containing the bag-like separator and the eight non-formed negative electrode plates were alternately laminated via a glass fiber-shaped separator to form each electrode plate group. After disposing these electrode plates in a battery case, an electrolytic solution was injected into the battery case to produce an unformed lead storage battery. The electrolytic solution was diluted sulfuric acid having a specific gravity of 1.26 (20 ° C.). Next, the unformed lead storage battery was formed at 9 A for 21 hours to complete the lead storage battery.

The lead-acid battery thus prepared was subjected to a JIS light load life test up to 3000 cycles, disassembled, and examined the number of confirmed short-circuits between the electrode plate and the strap. Three batteries of 12 V were made, and the number of cells was set to 18 cells, and these 18 cells were examined.

(Example 1) In Example 1, a portion corresponding to the lug of the negative electrode plate on the upper part of the bag-like separator 2 in which the positive electrode plate of the comparative example was inserted and the vicinity thereof were thermally fused over 4.5 cm. Using a battery sealed with the seal portion 2b and the entire area on both sides sealed with the seal portion 2b, a lead-acid battery was prepared in the same manner, and the same test was performed.

(Example 2) In Example 2, the upper part of the bag-like separator 2 in which the positive electrode plate of the comparative example was inserted was sealed with a sealing portion 2b formed by heat fusion in the same manner as in Example 1, and furthermore, on both sides. A lead-acid battery was prepared in the same manner as described above, using the one provided with the opening 7 at a height of 2 cm from the lower part of the bag-shaped separator 2 over 2 cm, and the same test was performed.

FIG. 3 shows the result of examining the number of short-circuits between the electrode plate and the strap in the tests of the lead storage batteries of Comparative Example, Example 1, and Example 2.

As described above, it was confirmed that the lead storage batteries of the comparative example had a large number of short circuits, whereas the lead storage batteries of the first and second embodiments of the present invention had a small number of short circuits.

[0025]

In the lead-acid battery according to the present invention, at least the portion corresponding to the lug of the counter electrode and the vicinity thereof are sealed at the upper part of the bag-shaped separator, so that the electrode plate has an extended portion and the counter electrode is formed. This can prevent the occurrence of an accident in which a short circuit occurs due to contact with the strap.

In particular, by sealing at least a portion corresponding to the ear portion of the counter electrode plate at the upper portion of the bag-shaped separator and the vicinity thereof and sealing the side portion of the bag-shaped separator while leaving a part thereof, diffusion of the electrolytic solution is prevented. There is no loss.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first example of an embodiment of an electrode group used in a lead storage battery according to the present invention.

FIG. 2 is a longitudinal sectional view showing a second example of the embodiment of the electrode group used in the lead storage battery according to the present invention.

FIG. 3 is a comparison diagram of the number of short-circuits between an electrode plate and a strap between Examples 1 and 2 of the lead storage battery according to the present invention and a comparative example.

FIG. 4 is a longitudinal sectional view of an electrode group used in a conventional lead storage battery.

FIG. 5 is a longitudinal cross-sectional view showing a state in which a plate group used in a conventional lead-acid battery is elongated and short-circuited to a strap of a partner plate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrode 1a Ear 1b Extension 2 Bag-shaped separator 2a Folded part 2b Seal 2c Opening 3 Electrode group 4 Strap 5a Ear 6 Strap 7 Open

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Keiichi Wada, Inventor 2-8-7 Nihonbashi Honcho, Chuo-ku, Tokyo Inside Shin-Kobe Electric Co., Ltd. (72) Inventor Shinkazu Tanaka 2-87 Nihonbashi Honcho, Chuo-ku, Tokyo Inside Shin-Kobe Electric Co., Ltd. (72) Yasushi Uraoka 2-8-7 Nihonbashi Honcho, Chuo-ku, Tokyo F-term inside Shin-Kobe Electric Co., Ltd. 5H021 BB11 CC18 EE04 5H028 AA05 BB01 BB05 CC05

Claims (2)

[Claims] 1. A lead-acid battery in which an electrode plate group in which at least one of a positive electrode plate and a negative electrode plate is accommodated in a bag-like separator is accommodated in a battery case, wherein an upper portion of the bag-like separator has at least a counter electrode. A lead-acid battery, wherein a portion corresponding to an ear of a plate and a portion in the vicinity thereof are sealed. 2. The lead-acid battery according to claim 1, wherein a side portion of the bag-shaped separator is sealed except for a part.