JPS6020463A - Lead storage battery - Google Patents

Abstract

PURPOSE:To improve the life performance of a lead storage battery by applying a thermoexpansive substance to a mat-like member prepared from either organic fiber or inorganic fiber alone or mixture of these fiber before the thus obtained body is heated and expanded to give elasticity to the mat-like member, then placing both the thus obtained member and a separator between plates. CONSTITUTION:Solution 1 is prepared by dissolving in solution of an acrylonitrile system latex, 20% of a thermoexpansive substance consisting of capsulated hollow microbaloons prepared by enclosing isobutane used as a blowing agent in shells consisting of a methylmethacrylate-acrylonitrile copolymer. After the solution 1 is applied to the entire surface of a 0.1mm. thick nonwoven polyester fibric 2 in 0.1mm. thickness, this is heated with a heating rollers 3 to 120 deg.C so as to expand the thermoexpansive substance thereby obtaining a nonwoven- fabric mat-like member 4 of 0.5mm. thickness. Next, the thus obtained mat-like member 4 and a separator 2 are stuck together to make a roll which is then cut to a given length. The thus formed members with a given length are placed between positive plates 6 and negative plates 5 to make a plate group 7 which is used in constituting a lead storage battery.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lead-acid battery, and uses an inexpensive and highly elastic mat for preventing active material from falling off, which is inserted together with a separator between the anode plates.

The purpose is to improve battery life performance.

Traditionally, it has been used in lead-acid batteries to prevent the electrode active material from falling off due to vibration and repeated charging and discharging.

A mat-like material made of glass fiber (hereinafter referred to as glass mat) was stacked together with seven pallets and inserted between the negative and anode plates. but.

The glass mat had the following drawbacks.

(1) The cost of glass mats is high.

(2) Handling is difficult because the glass fibers stick into hands.

(3) Automation of the battery assembly process was hindered because a long continuous p-type product could not be obtained.

The present invention eliminates the above drawbacks.

A thermally expandable substance is applied to a mat-like material obtained by using ta fibers or inorganic fibers alone or by a mixture of both, and then the thermally expandable material is heated and expanded to give elasticity to the mat-like material. By giving sex.

This mat exhibits effects superior to those of the glass mat described above, and will be explained in detail in Examples below.

Example 1 As shown in Fig. 1, 1, a hollow i-cycloparoon formed from a copolymerized shell of methyl methacrylate-acrylonitrile encapsulated with isobutane as a blowing agent in an acryl-tetranitrile latex solution. A solution containing 20% of an expandable substance was applied to the entire surface of the nonwoven fabric 2 to a thickness of 0.1 mm each, and then heated to 120"C with a heating roll 6. .

PIt thermally expandable substances! A mat-like material 4 of non-woven fabric having a thickness of 0.5 mm was obtained by swelling.

The mat-like material 4 of the present invention, the conventional glass mat, and the glue R
Figure 2 shows the results of comparing the strength.

As shown in FIG. 2, the mat-like material 4 of the present invention exhibits less change in thickness under load than a glass mat and is highly elastic. Furthermore, it was confirmed that even when the load on the mat-like material 4 was removed, it recovered to 100% of its original thickness.

Furthermore, since the polyester nonwoven fabric 2 is continuously produced,
7 Since the F-shaped material 4 can be made into a long roll of 1000 to 20001 F+, lamination with acid- and oxidation-resistant and flexible synthetic resin 7 pallets can be performed continuously at high bending.

He cut the thus obtained mat material and separator together to the length of the yarn, and inserted it between the cathode plate 5 and the anode plate B, as shown in Figure 6. Table 1 shows the results of a comparison between a lead-acid battery using a frame plate TRF7 constructed using the same structure and a conventional lead-acid battery using a glass mat instead of a mat-like material. As shown in Table 1, the second invention
1. The life of the front battery has been extended significantly compared to conventional batteries because 1. The elastic mat-like material reduces the possibility of electrode plate active material falling off, and the mat-like material is used to side-seal the electrode plate. This is due to the fact that it was possible to prevent short circuits. As for the battery cost, the mat-like material costs 0.
Starting from one piece of non-woven fabric, it has become cheaper because it can be made to a thickness of 0.5 crocodile shoulder with the same weight, and since it is a continuous spring item, there is no need to paste it with a separator. By being able to do it continuously and shortening the electrode plate packaging process to a large IJ, we were able to quickly achieve a 5% cost reduction.

Example 2 A solution containing 50% of a thermally expandable substance made of a hollow microballoon formed from a vinylidene chloride-acrylonitrile copolymer shell encapsulated with isobutane as a blowing agent in an acrylic binder was mixed into a thick solution. SaQ,
After coating the entire surface of a 1 mm glass mat with a thickness of 0.1 mm, the mixture was dried and heated at 120°C to expand the thermally expandable material to obtain a glass mat with a thickness of 0.5 mm.

Four pieces of glass mats were obtained in this way.

Shade overlaid with a separator that has oxidation resistance.

It was inserted between the anode plates to form a lead-acid battery. As a result, since the porosity of the Karasu mat is improved, a large amount of electrolyte can be held between the electrode plates, so that a battery with excellent discharge performance and low cost can be provided.

The shell of the thermally expandable material used in the present invention is as follows.

In addition to those shown in the above examples, a copolymer of vinyl chloride = lJ dendemyl methacrylate and acrylonitrile can be used, and as a blowing agent, petroleum ether can be used in addition to isobutane. The above phases are particularly acid resistant and
The formation of hollow microballoons is very stable.

However, thermally expandable materials made of other chipping-resistant and butylation-resistant phase materials can also be applied to the present invention.

In addition to the above examples, it is also possible to use a mat-like material obtained by mixing organic fibers and inorganic fibers. It can be made into a mat-like material.

As mentioned above, the present invention uses a mat-like material that has more elasticity than a glass mat, and packaging the electrode plate by heat sealing takes a lot of time, resulting in excellent productivity and significantly improving battery performance. It has a great industrial value.0

[Brief explanation of drawings]

FIG. 1 is a side view of the mat-like product of the present invention being manufactured. FIG. 2 is a diagram showing the thickness ratio of the mat-like material of the present invention and the conventional glass mat with respect to the load, and FIG. 3-1 is a plan cross-sectional view of an electrode plate group using the mat-like material of the present invention. 2: Non-woven fabric 3 = Heating roll 4: Mat-like material Applicant: Yuasa Battery Co., Ltd.

Claims (1)

[Claims] 1) In a lead-acid battery in which a separator and a mat-like material obtained by overlapping organic fibers or inorganic fibers or a mixture of both are inserted between negative and anode plates, the mat-like material A lead-acid battery characterized in that elasticity is imparted to the mat-like material by applying a thermally expandable substance to the material and heating the thermally expandable material to cause it to swell. 2) A patent characterized in that the thermally expandable substance is a hollow microballoon made of a vinylidene chloride-acrylonitrile, methyl methacrylate-acrylonitrile, or vinylidene chloride-methyl methacrylate-acrylonitrile copolymer shell containing gas or liquid. A lead-acid battery according to claim 1.