JPS62154456A - Lead-acid battery - Google Patents

Abstract

PURPOSE:To increase active material holding effect to lengthen the life of a battery by using a bag-shaped liquid-absorbing mat separator. CONSTITUTION:Free electrolyte is contained in the upper part of electrode plates. A liquid-absorbing mat separator 1 made of a mixture of very fine glass fibers and 5-40% synthetic resin, and containing inorganic powder such as silica and deatomaceous earth in its inside is formed in a bag shape to wrap a cathode plate or an anode plate. The mat separator has a maximum pore size of 100mum and a thickness of 0.8mm (under a pressure of 20kg/cm<2>). Thereby falling off of softened cathode active material is prevented and the life is lengthened.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a lead-acid battery having a free electrolyte up to the top of the electrode plate group.

(Prior Art) Conventionally, various types of separators have been used as separators for lead-acid batteries. For example, there are flat separators made by laminating acid-resistant paper and glass mats, sheet separators made of polyethylene, and the like.

Although these separators are effective in preventing short circuits between the anode and the cathode and fulfill their original role, they are not sufficient in preventing the softened active material from falling off. When using a flat separator made by pasting paper and glass mat together.

Normally, attempts have been made to bring a glass mat into contact with the anode plate to prevent the anode active material from falling off due to softening, but the effect is not sufficient because the fiber diameter of the glass mat is large and the porosity is extremely high.

(Problems to be Solved by the Invention) Calcium extract batteries are becoming popular as a solution to the above problem, but since this type of battery does not have vertical frame ribs for the electrode plates, if a flat separator is used, the side The risk of short-circuiting is extremely high, and the separator must be packaged in a bag. There are adhesives, heat welding, ultrasonic welding, etc. as joining methods for making bags, but when joining by heat welding or ultrasonic welding, if the content of synthetic fiber is 5% or less, welding cannot be done at all. Alternatively, there was a drawback that sufficient welding strength could not be obtained.

On the other hand, the maximum pore diameter of the separator must be 100JJn+ or less; if the maximum pore diameter is larger than this, there is a risk that the softened anode active material will short-circuit through the separator. Moreover, when the thickness of the separator is thin, the amount of sulfuric acid contained in the separator decreases, resulting in a disadvantage that the initial characteristics deteriorate.

An object of the present invention is to eliminate the conventional drawbacks and provide a lead-acid battery having a free electrolyte up to the top of the electrode plate group, which prevents the softened positive electrode active material from falling off and has a longer life. .

(Means for Solving the Problems) The lead-acid battery of the present invention has a free electrolyte up to the top of the electrode plate, and is made of a mixture of extremely thin glass fibers and 5% to 40% synthetic fibers. A liquid-absorbing mat separator containing inorganic powder such as silica or diatomaceous earth is used, and this is made into a bag to wrap either the anode plate or the cathode plate, and the maximum pore diameter of the mat separator is 100 μm or less, and the thickness is 0.8 mm (20 kg
/- when pressurized) or more.

(Example) An example of the present invention will be described based on FIGS. 1 and 2.

FIG. 1 is a block diagram of a lead-acid battery according to the present invention. In the figure, 1 is a bag-formed mat-like separator, 2 is a welded part for bag-forming, 3 is an electrode plate included in the bag-formed mat-like separator 1, and 4 is an ear part of the electrode plate 3. be.

With conventional technology, the ability to retain the softened active material was not sufficient, so batteries often reached the end of their lifespan prematurely. However, when the pine 1-shaped separator of the present invention is used in a bag, it not only has a sufficient function of holding the active material, but also eliminates the risk of side shorting.

In order to clarify the effects of the present invention, 5. Lead-acid battery A according to the present invention (thickness of mat-like separator: 1.0 mm), lead-acid battery B using mat-like separator without bagging, thickness 0
．． Battery C using a 5mm mat-like separator; Battery E using a polyethylene sheet separator made into a bag; Battery made by pasting paper and glass mat together using conventional technology;
A comparative test was conducted with. Note that the bagged separator contained an anode plate. In addition, all electrode plates used were calcium extract band electrode plates. The test is 5502 with the above configuration
Batteries equivalent to No. 3 were manufactured as prototypes and subjected to a JIS life test. The results are shown in FIG.

The lifespan was in the following order: E<D<B<CaA. Although A and C had approximately the same lifespan, in the case of C, the initial characteristics were significantly degraded.

As a result of disassembling and investigating the battery after the life test, E and D
In case of B, there was a lot of softened active material falling off at the bottom, and in case of B, the separator held the softened active material, and it functioned satisfactorily, but a side short was observed, and it was judged that the life had come to an end. .

A was because the softened active material was sufficiently retained.

It was good with little sediment at the bottom.

(Effects of the Invention) According to the present invention, by using a liquid-absorbing matte separator in a bag, the effect of retaining the active material is extremely high compared to conventional separators, and it is possible to extend the life of the battery. .

[Brief explanation of drawings]

, FIG. 1 is a block diagram of a lead-acid battery according to an embodiment of the present invention, and FIG. 2 is a diagram showing the life test results of the lead-acid battery of the present invention and a conventional example. 1... Separator, 2... Welding part, 3... Electrode plate, 4... Ear part of electrode plate. Patent applicant: Matsushita Electric Industrial Co., Ltd. The agent is Hisashi Hoshino.1-1. Figure 1 Figure 2 Sai Uno L Soft (B)

Claims (2)

[Claims] (1) It has a free electrolyte up to the top of the electrode plate, and is a mixed paper made of extremely thin glass fibers and 5% to 40% synthetic fibers, and inorganic powder such as silica and diatomaceous earth is contained inside the mixed paper. 1. A lead-acid battery characterized by using a liquid-absorbing mat-like separator, which is made into a bag, and wrapping either an anode plate or a cathode plate. (2) Claim (1) characterized in that the maximum pore diameter of the mat-like separator is 100 μm or less, and the thickness is 0.8 mm or more (when 20 kg/cm^2 pressure is applied).
Lead-acid batteries as described in section.