JPS61232559A - Clad type sealed lead-acid battery - Google Patents

Abstract

PURPOSE:To reduce softening and coming off of active material and increase charge-discharge cycle life by surrounding the core of positive plate with active material and strongly holding the periphery of the active material by tube. CONSTITUTION:A clad type positive plate using a lead-alloy core 1 and a porous tube 2 having liquid absorbing ability and acid resistant and oxidization resistant capability is faced to a negative plate comprising a lead alloy grid with a mat-like separator 7 comprising acid-resistant hydrophilic fibers interposed between them and compactly stacked. Since the core of the positive plate is surrounded with an active material 3 and the periphery of the active material is strongly held by tube 2, softening and coming off of the active material are reduced and charge-discharge cycle is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an improvement in a clad-type sealed lead-acid W battery.

Conventional technology and its problems Sealed lead-acid batteries use pasted positive and negative electrode plates with substantially antimony-free lead alloy grids, and the electrolyte is gelled or impregnated into a porous separator. Those that have been developed are generally put into practical use. Since this type of battery does not substantially contain antimony in the lattice alloy, there are problems in that the lattice elongates significantly, the active material softens and falls off significantly, and the charge/discharge cycle life is short.

Means for Solving the Problems The present invention provides a clad positive electrode plate using a lead alloy core metal substantially free of antimony and a porous tube that is highly liquid-absorbing and is resistant to acid and oxidation. The negative electrode plate is made of a lattice made of lead alloy that does not contain antimony, and the porosity is 90% made of acid-resistant and hydrophilic fibers with a diameter of 10 microns or less.
It is characterized by a sealed lead-acid battery using an oxygen cycle reaction in which an electrolytic solution is impregnated and held in a group of electrode plates closely stacked facing each other with a mat-like separator in between.

Embodiment An embodiment of the lead-acid battery according to the present invention is shown in FIGS. 1 and 2. In the figure, 1 is a lead alloy containing substantially no antimony, such as a lead-calcium-tin-aluminum alloy, or a lead-antimony alloy containing 1% or less of antimony.
A core metal made of an arsenic-tin alloy or the like, 2 a porous tube that is resistant to acid and oxidation and has high liquid absorption properties, 3 a positive electrode active material, 4 an upper lead alloy joint, and 5 a lower joint. 5 constitutes a clad positive electrode plate. 6 is a negative electrode plate using a lattice made of a lead alloy that does not substantially contain antimony, such as a lead-calcium alloy, and 7 is an acid-resistant and hydrophilic material having a diameter of 10 microns or less, such as alkali-containing glass, hydrophilic polyethylene, or polyester. This is a mat-like separator with a porosity of 90% or more, made of fibers made of acrylonitrile, polyester, etc. The positive electrode plate and the negative electrode plate 6 are closely stacked so as to face each other with the separator 7 interposed therebetween to form an electrode plate group.

8 is a battery case, 9 is a lid, 10 is a valve fixed to a part of the lid, 11 is a positive terminal, and 12 is a negative terminal.

The electrolyte is dilute sulfuric acid, which is impregnated into the positive and negative electrode plates and the separator.

Since the separator 7 is made of a hydrophilic material and has a highly porous mat shape, it has excellent liquid retaining properties and is highly elastic, and is partially deformed within the tightly laminated electrode plate group.

Therefore, it is possible to maintain sufficient contact between the flat negative electrode plate and the positive electrode plate having a large number of tubes connected to each other to conduct current due to charge/discharge reactions between the two, thereby ensuring ionic conduction. That is, the separator 7 is in contact with the porous tube 2 over a fairly wide area, allowing the positive electrode active material 3 to be charged and discharged. Furthermore, the gas space 13 formed between the tube 2 and the separator 7 also functions as a passage for diffusing the oxygen gas generated from the positive bridge plate to the negative electrode plate, so the sealing reaction efficiency is high and the Water loss can be suppressed.

The reason why a mat made of fibers made of a hydrophilic material and having a diameter of 10 microns or less is used as a separator is to allow the oxygen cycle reaction to proceed smoothly and to sufficiently retain the electrolyte. When the mat is normally molded, the porosity of this mat is 90% or more.

Next, Table 1 shows the results of a charge/discharge cycle test of the sealed lead-acid battery according to the present invention shown in the drawings, in comparison with that of a conventional paste-type closed-loop battery. All lattice alloys were lead-calcium-tin alloys with the same composition. Further, discharging was performed at a rate of 1 hour to a terminal voltage of 1.0 V/cell, and charging was performed at a constant voltage of 2.4 V/cell for 7 hours.

Table 1 Effects of the Invention In the positive electrode plate of the battery according to the present invention, the core metal is surrounded by an active material,
In addition, since the outer periphery is firmly held by the tube, the active material is less likely to soften or fall off, and can withstand 111 charge/discharge cycles. In addition, the separator is a porous mat with excellent liquid retention and high elasticity.
Sufficient contact with the positive and negative electrode plates can be obtained, sufficient ionic conduction between the two electrode plates can be ensured, and good battery performance can be obtained.

Furthermore, the gas space formed between the tube and the separator functions as a diffusion path for oxygen gas generated at the positive electrode plate to the negative electrode plate, so that the sealing reaction efficiency is high. As described above, according to the present invention, it is possible to provide a clad-type sealed battery that has good performance and a long charge/discharge cycle life.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical cross-sectional view of the main parts of a clad-type sealed lead-acid battery according to the present invention, and FIG. 2 is a schematic cross-sectional view of the main parts. 1... Core metal made of a lead alloy that does not substantially contain antimony, 2... Porous tube, 3... Positive electrode active material,
6...Negative electrode plate using a lead alloy lattice that does not substantially contain antimony, 7...Matte separator, 13...
gas space

Claims (1)

[Claims] 1. A clad positive electrode plate that uses a lead alloy core metal that does not substantially contain antimony and a porous tube that is resistant to acid and oxidation with high liquid absorption properties, and a lattice that is made of a lead alloy that does not substantially contain antimony. An electrolytic solution is applied to a group of electrode plates in which a negative electrode plate made of carbon dioxide is closely stacked so as to face each other through a mat-like separator with a porosity of 90% or more made of acid-resistant and hydrophilic fibers with a diameter of 10 microns or less. Clad-type sealed lead-acid battery with impregnated and retained oxygen cycle reaction.