JPH0693356B2 - Outer bag for sealed lead acid battery - Google Patents

Description

The present invention relates to a sealed lead acid battery, and more particularly to an outer bag made of a plastic film or a sheet for accommodating an electrode plate group.

[Conventional technology]

The sealed lead-acid battery is widely used as a compact power source that is convenient for carrying because the electrolyte does not overflow outside the battery case because the separator such as the glass mat holds the electrolyte and does not flow.
Recently, a battery using a plastic film or sheet has been developed as a battery case material for this sealed lead acid battery. One example is shown in FIG. In the figure, an electrode plate group 1 (consisting of a positive electrode plate, a negative electrode plate and a separator) having two polarities 2 is packed in an outer bag 3 made of a plastic film or a sheet, and an electrolytic solution (not shown) is contained therein. To form a lead acid battery. Reference numeral 4 is a check valve that allows internal gas to escape to the outside.

The manufacturing of the outer bag 3 used here and the operation of inserting the electrode plate group 1 into the bag will be described with reference to FIG.

Two films or sheets are superposed, and the seal portions 5 and 6 on both side edges and the seal portion 7 on the upper end are sealed. In addition, the upper end is partially sealed, and a hole 8 for inserting the check valve 4 and the pole 2 is formed.

The outer circumference 9, 10, 11, 12 is cut to a predetermined size.

The electrode plate group 1 is inserted through the opening 13 at the lower end and set on the electrode plate insertion installation portion indicated by the broken line. At this time, the pole 2 has a hole 8 at the upper end.
From the outside.

The inner surface of the outer bag forming the hole 8 and the pole 2 are sealed, and the hole 8 is closed.

Inject electrolyte.

Seal the seal portion 14 at the lower position of the electrode plate group 1 and
Seal.

The outer periphery 15 of the seal portion 14 is cut.

Through the above steps, the lead acid battery shown in FIG. 3 is completed.

[Problems to be Solved by the Invention]

Through the above steps, when manufacturing the lead storage battery, the inner bag b ₁ in FIG. 4 has an inner dimension b ₁ of the electrode plate group 1 so that the electrode plate group 1 can be inserted from the lower end opening 13 as the outer bag 3 used. A material sufficiently larger than the outer dimension a is used.
However, it has been found that various problems occur when the inner dimension b ₁ is made larger than the outer dimension a of the electrode plate group 1. That is, (1) The distance c ₁ between the seal parts 5 and 6 on both sides of the bag 3 and the electrode plate group ₁
Becomes larger, and the electrolytic solution accumulates in this area. The electrolytic solution in this part lowers the liquid level during initial charging or electrogalvanization, so the electrode plate is exposed and charging is not completed, resulting in deterioration of battery performance.

(2) As shown by the broken line in FIG.
When the direction of the electrode plate group 1 is not stable when it is inserted through the opening 13 at its one end, the polarity 2 hits the seal portion 7.
As a result, the pole 2 is bent and the seal portion 7 is damaged.

(3) Also, as shown by the broken line in FIG. 6, the center X of the electrode plate group 1 and the center Y of the bag 3 do not coincide with each other, and the pole 2 approaches the seal portion 7 near the check valve 4. There is. In this case, pole 2
When a lead wire or the like is soldered to the tip 2A of the, the seal portion 7 is deformed due to the heat of the solder, which causes the function of the check valve 4 to deteriorate.

The present invention has been made to solve the above-mentioned problems, and it is a closed type in which the electrode plate group can be easily and accurately inserted into the outer bag and the excess electrolyte solution accumulation portion can be reduced. An object is to provide an outer bag for a lead storage battery.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, the present invention inserts and installs the electrode plate group in an outer bag having a hole for projecting the electrode column at one end and an opening for inserting the electrode plate group at the opposite end. The inner size of the installation part is close to the outer size of the electrode plate group so that the inserted electrode plate group can be set at the correct position, but the inner size of the opening for inserting the electrode plate group is the electrode plate insertion installation described above. It is provided with a structure in which it is made larger than the internal dimension of the part.

[Action]

According to the present invention, when the electrode plate group is inserted through the opening at one end of the outer bag, the inner size of the opening is large, so that the electrode plate group can be easily inserted. When the insertion installation portion is inserted into the inside of the inside of the inside of the insertion installation portion, the inside dimension of the insertion installation portion is close to the outside dimension of the electrode plate group, so that the electrode plate group is automatically set at a predetermined accurate position. Furthermore, in a lead-acid battery made using this bag, there is not much extra space between the electrode plate group and the outer bag, so there is little accumulation of electrolyte and efficient initial charging or electrolytic formation is possible. Has the effect of.

〔Example〕

 Embodiments of the present invention shown in the drawings will be described below.

FIG. 1 is a plan view showing an outer bag 3 according to an embodiment of the present invention. The outer bag 3 is formed by stacking two films or sheets and sealing the three-sided sealing portions 5, 6, 7 shown by hatching to form a flat rectangular shape with one end (lower end) opened. At the upper end of this bag 3, there is formed a hole 8 through which the check valve 4 is formed and the pole 2 is projected, and the opening 13 at the opposite end (lower end) is an opening for inserting the electrode plate group 1. Make up. The inner dimension between the seal portions 5 and 6 on both side edges is set to be large at the opening 13 and small at the electrode plate insertion installation portion. That is, the seal portions 5A and 6A near the opening 13 have a smaller width than the outer dimension a of the electrode plate group 1 so that the inner dimension b ₁ of the opening 13 facilitates the insertion of the electrode plate group 1. It is set quite large. On the other hand, in the electrode plate insertion installation part, the internal dimension b ₂
Is as close as possible to the outer dimension a of the electrode plate group 1 as long as the insertion of the electrode plate group 1 is allowed, and therefore the width of the seal portions 5C and 6C in this portion is set to be large. It should be noted that inclined seal portions 5B and 6B are formed between the seal portions 5A and 5C and between the seal portions 6A and 6C so as to prevent a step from being formed therebetween.

In using the outer bag 3 having the above structure, first, the electrode plate group 1 is inserted through the opening 13 at the lower end thereof. At this time, since the opening 13 has a sufficiently large size, the electrode plate group 1 can be easily inserted. After that, the electrode plate group 1 is pushed inward of the outer bag 3, and at that time, it is automatically guided to the center of the bag 3 by being guided by the seal portions 5B, 6B and 5C, 6C, and has a correct posture. , And is positioned at the exact position indicated by the broken line in FIG. After this, after the hole 8 is sealed and the electrolytic solution is injected, the opening 13 is directed upward for initial charging or electrolytic formation, the seal portion 14 is sealed, and the outer periphery is cut, A lead storage battery as shown in FIG. 3 is formed. In this lead acid battery, the distance c ₂ between the seal parts 5C and 6C and the electrode plate group 1 is extremely small, and therefore, there is no extra reservoir of the electrolytic solution, and the initial charge or electrolytic formation can be efficiently performed.

In the above embodiment, the wide seal portions 5C and 6C are formed over substantially the entire length of the electrode plate group 1, but this portion may be shortened. FIG. 2 shows an example in that case, in which the wide seal portions 5C and 6C are formed by a length m shorter than the total length 1 of the electrode plate group 1. In this embodiment, compared with the embodiment shown in FIG. 1, the amount of accumulated electrolyte is slightly larger, but is much smaller than that shown in FIG. 4, and similar to the embodiment shown in FIG. The electrode plate group 1 can be accurately inserted at a predetermined position.

In each of the above examples, the outer bag is formed by stacking two films or sheets and sealing the both side edges symmetrically, but instead, the sheet portion on one side edge has a constant width. The width of only the other seal portion may be changed. Also, instead of using two films or sheets, a bag or a seal portion formed by folding one film or sheet and using the fold as one side edge and sealing the opposite side edge is provided on the back of the bag. It is also possible to apply the present invention to bags arranged in parts.

As the material of the film or sheet constituting the outer bag of the present invention, various plastic films or sheets having heat sealability can be used. However, due to the characteristics such as heat sealability, burst strength, tensile strength and gas barrier property, The laminated material shown in is suitable. That is, one or more layers of thermoplastic synthetic resin such as polybutylene terephthalate, polyethylene terephthalate, polycarbonate, polyethylene, polypropylene, polyvinyl chloride, nylon, etc. and a barrier layer are laminated on the outside of an inner layer made of a polyolefin resin layer. Is.

Here, as the polyolefin resin, low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene and their copolymers such as ethylene vinyl acetate copolymer, ethylene acrylic acid copolymer, ethylene Methacrylic acid copolymer, ethylene acrylic acid ester copolymer, ethylene methacrylic acid ester copolymer, ethylene-propylene copolymer and terpolymer can be used.

Further, as the above acid modified product, kraft polymerization modification is carried out with an unsaturated carboxylic acid such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, citraconic acid, citraconic anhydride, itaconic acid or itaconic anhydride or an anhydride thereof. May be. Those having a carboxylic acid group are sodium Na ⁺ ,
An ionomer cross-linked with a metal ion such as zinc Zn ⁺⁺ can also be applied.

As the barrier layer, a layer of polyvinylidene chloride, saponified ethylene vinyl acetate copolymer, polyacrylonitrile, acrylonitrile copolymer, or polyvinyl alcohol may be used.

For the lamination of the film or sheet in the production of the above synthetic resin laminated material, known methods such as dry lamination using urethane-based, polyester-based, ethylene vinyl acetate copolymer-based resin as an adhesive or extrusion lamination are used. Although it can be used, the innermost layer of the polyolefin film is preferably dry laminated from the viewpoint of resistance to internal solution and adhesive strength.

Sufficient tensile strength and burst strength can be obtained by compounding the film, but when a so-called net-like material made of woven fabric of stretched yarn such as polyolefin or polyester is laminated inside, these are dramatically improved. .

This laminated film may be used not only as a single layer but also as a double bag or triple bag structure in which a polyolefin film is further laminated. By doing so, the pinhole resistance during bending is improved, the bag is also flexible, and liquid leakage due to bag breakage can be prevented.

〔The invention's effect〕

As described above, in the outer bag of the present invention, the inner dimension of the electrode plate insertion installation portion for inserting and installing the electrode plate group is set outside the electrode plate group so that the inserted electrode plate group can be set at an accurate position. Although the size is close to the size, the inner size of the opening for inserting the electrode plate group is set to be larger than the inner size of the electrode plate insertion installation portion, so that the electrode plate group can be easily inserted into the outer bag. However, by simply pushing it into the bag, the electrode plate group can be automatically set accurately at a predetermined position in the bag, and at that time, the electrode plate group can be set in a predetermined posture. Since the pole column does not hit the seal part and is not damaged because it is inserted, no electrolyte solution is required when the electrode plate insertion installation part of the outer bag is sealed and electrolyte solution is injected. Since there are few pools and the liquid surface is high, the electrode can be charged during initial charging or electrolytic formation. Decrease in battery performance due to exposure has excellent effects such as to be prevented.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention, FIG. 2 is a plan view showing another embodiment, FIG. 3 is a perspective view showing a conventional lead storage battery, and FIG. 4 is a conventional outer bag. The plan views, FIG. 5, and FIG. 6 are plan views for explaining the problems of the outer bag of FIG. 4, respectively. 1 …… Pole plate group, 2 …… Pole column, 3 …… Outer bag, 4 …… Check valve, 5,6,7 …… Seal part, 8 …… Hole, 5A, 5B, 5C …… Seal part , 6A, 6B, 6C …… Seal part

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Minor Yoshinaka Minami 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Nobuo Aoyagi 1-1-1, Tanikaga-cho, Shinjuku-ku, Tokyo Within Nihon Printing Co., Ltd. (56) References: 59-148071 (JP, U)

Claims (2)

[Claims] 1. An outer bag for accommodating a substantially rectangular electrode plate group having a pair of pole columns projecting substantially in parallel from one side, the bag having a substantially flat rectangular shape and having the pair of poles at one end. In an outer bag having a hole for projecting a column and an opening for inserting the electrode plate group at the opposite end, the inside dimension (b ₂ ) of the electrode plate inserting and installing portion for inserting and installing the electrode plate group is inserted. Outer dimension (a) of the electrode plate group so that the electrode plate group can be set at an accurate position.
For a sealed lead-acid battery characterized in that the inner dimension (b ₁ ) of the opening for inserting the electrode plate group is made larger than the inner dimension (b ₂ ) of the electrode plate insertion installation portion. Outer bag. 2. The rectangular bag is formed by sealing three sides of two plastic films or sheets, and the remaining one side is an opening for inserting a polar plate, and the opening is sandwiched. The outer bag for a sealed lead-acid battery according to claim 1, wherein the width of the seal portions on both sides is narrow at the opening and wide at the electrode plate insertion installation portion.