JPH1032018A - Sealed type lead-acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an electrolyte from coming into a layer form, and to realize a long service life, by providing partition plates which are the structure not to permeate the electrolyte, and have upward projections on the outer periphery, in an electrode group arranging electrode surfaces horizontally. SOLUTION: Positive electrodes 1 and negative electrodes 2 are layered through separators 4 to make their operating surfaces horizontal, and they are composed to make the positions of electrodes opposite at the upper side and the lower side of the partition plates 3. An electrode group which consists of plural sets of them is housed in a battery jar 6, and the electrodes of the same polarity are connected to connectors 5 at the tips of their projections 1a and 2a. Around the partition plates 3 which consist of thin plates of a polyethylene or the like, projections 3a, and cutting parts 3b where the projections 1a and 2a are fitted, are provided to prevent the dropping of the electrolyte. And the partition plate 3 is composed of a sheet of a lead or a lead alloy, and it may be a collector concurrently. And it is preferable that a laminate body of an acidproof and oxidation-proof sheet having a through hole to which an active material is filled, and a sheet of lead or a lead alloy, is used to the electrodes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealed lead-acid storage battery.

[0002]

2. Description of the Related Art A sealed lead-acid battery has a function of absorbing oxygen gas generated from a positive electrode at the time of charging by a negative electrode, has no gas discharge outside the battery, and has no leakage of electrolyte during use. have. This battery, in order to impart the above characteristics, by limiting the amount of the electrolyte, a positive electrode, a negative electrode, and impregnated and held with the electrolyte in a group of electrodes consisting of a separator also serving as an electrolyte holder generally called a retainer. In order to prevent excess electrolyte solution from freely moving in the battery case.

[0003] Such a battery is generally arranged such that the electrode surface is in a vertical direction. When the battery is used in a cycle application in this state, sulfuric acid is consumed by discharging, the specific gravity of the electrolyte decreases, and the battery is formed by charging. Since the sulfuric acid gradually moves downward due to the gravity, uneven distribution (stratification) of the electrolyte concentration occurs above and below the electrode group. When the stratification of the electrolytic solution occurs in this manner, it is difficult to charge the active material below the electrode group having a high concentration of the electrolytic solution, and there is a problem that the capacity of the battery is reduced and the life is shortened.

In order to solve this problem, there have been proposed a large number of retainer-type batteries having a structure in which electrode groups are arranged so that the electrode surfaces are horizontal, so that stratification of the electrolyte is hardly caused. Such a battery had better life performance than a battery in which the electrode surfaces were arranged in a vertical direction.

[0005] However, even in a battery in which the electrode surfaces are arranged horizontally, since the electrode plate and the separator are porous, the electrolyte moves downward, and eventually the electrolyte is stratified and the life of the battery is reduced. Was still shorter. Therefore, a retainer type battery in which a partition plate impermeable to the electrolyte is inserted into the electrode group to prevent stratification of the electrolyte is disclosed in Japanese Patent Application Laid-Open No. 61-1986.
74266 and JP-A-64-60972.

[0006]

However, when such a battery is charged, the electrolyte retained in the retainer and the electrodes is discharged from the electrode group by the hydrogen gas and oxygen gas generated from the electrodes and flows. Overflows as an electrolyte,
Since the separator fell downward from the periphery of the partition plate, the content of the electrolyte changed above and below the electrode group, and the electrolyte was stratified.

The present invention has been made to solve the above problems, and it is an object of the present invention to provide a lead storage battery having a longer life performance by preventing stratification of an electrolytic solution in an electrode group.

[0008]

In order to solve the above-mentioned problems, the present invention provides a positive electrode and a negative electrode which are overlapped via a separator to form a pole group, and the pole group is arranged so that the electrode surface is horizontal. In the sealed lead-acid battery described above, a partition plate through which an electrolyte does not permeate and which has at least an upward projection around the electrode group is arranged in the electrode group.

It is preferable that the partition plate also serves as a current collector for the electrodes in order to reduce the number of parts and reduce the weight of the battery.

The electrode may be formed by laminating an acid- and oxidation-resistant sheet having a large number of through holes filled with an active material and a lead or lead alloy sheet.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a schematic sectional view showing an embodiment of the present invention, FIG. 2 is a perspective view showing a partition plate of FIG. 1, 1 is a positive electrode, 2 is a negative electrode, and 3 is a partition. Plate, 4 is a separator made of a glass mat of fine fibers, 5 is a connector, 6
Is a battery case, and 7 is a safety valve. The partition plate 3 is made of a thin plate made of a material impermeable to an electrolytic solution, for example, polyethylene, and has upward projections 3a around its periphery as shown in FIG. 2, and a part thereof is cut away. The notch 3b has the electrode 1,
The electrode 1 or 2 is stacked on the upper surface of the partition plate 3 by fitting the two protrusions 1a, 2a.

As described above, the positive electrode 1 and the negative electrode 2 are stacked via the separator 4 so that their respective working surfaces are horizontal, and the positions of the respective electrodes are reversed above and below the partition plate 3. I have. In this manner, a pole group including the positive electrode 1, the negative electrode 2, and the separator 4 each having six sheets and the partition plate 3 having five sheets is configured. The electrodes of the same polarity of this pole group are connected by a connector 5 at the tips of the protrusions 1a and 2a.

After storing such an electrode group in the battery case 6 and injecting a dilute sulfuric acid electrolyte having a specific gravity of 1.32, a safety valve 7 was attached, and a battery A of the present invention having a capacity of 10 Ah was produced at a rate of 3 hours.

(Embodiment 2) FIG. 3 is a schematic sectional view showing another embodiment of the present invention, and FIG. 4 is a perspective view showing a partition plate serving also as a current collector of FIG. Indicates the same name. The partition plate 3 of the present embodiment is made of a lead or lead alloy sheet, and has upward and downward projections 3a around the periphery and projections 3c extending horizontally from the side surfaces as shown in FIG. Active materials 1 a and 2 a having the same polarity are applied to both sides of the upper surface and the lower surface of the partition plate 3 to form the positive electrode 1 or the negative electrode 2. In other respects, Battery B of the present invention similar to that of Embodiment 1 was produced.

The uppermost and lowermost partition plates 3 have projections 3a only on the lower and upper sides, respectively, and the active material 2a, 1a is applied only on each side.

(Embodiment 3) FIG. 5 is a schematic sectional view showing still another embodiment of the present invention, and FIG. 6 is a plan view showing the electrode of FIG. 5, and the same reference numerals as those in Embodiment 1 denote the same names. .

The positive electrode 1 and the negative electrode 2 are 4 cm long, 7 cm wide,
ABS resin sheets 1b and 2b having a thickness of 1.0 mm and Pb-Ca-Sn-based alloy sheets 1c and 2c having a thickness of 0.2 mm
Is adhered. As shown in FIG. 6, a large number of circular through holes 1d and 2d having a diameter of 3.1 mm are formed in the ABS resin sheets 1b and 2b so that the porosity is 80% except for the peripheral portion. , 2d are filled with a positive electrode active material 1e and a negative electrode active material 2e, respectively. The positive electrode 1 and the negative electrode 2 are alternately stacked such that the working surfaces are horizontal and the working surfaces of the positive and negative electrodes are opposed to each other, and a separator made of glass fiber is provided between each of the resin sheets 1d and 2d. 4 are inserted, and a partition plate 3 made of a polyethylene film is inserted between the respective alloy sheets 1c and 2c to form a pole group.

The partition plate 3 has upward and downward projections 3a around its periphery, a part of which is cut out, and a part of the alloy sheets 1c and 2c laminated on the upper surface and the lower surface outward from the notch. Extend, and one ends 1 a and 2 a of the same polarity are connected to each other by a connection body 5. A part of the connection body 5 penetrates the side wall of the battery case 6 and projects outside the battery case.

After such an electrode group was housed in the battery case 6, a dilute sulfuric acid electrolytic solution having a specific gravity of 1.32 was injected, and a safety valve 7 was attached to produce a 10-Ah battery C of the present invention at a 3-hour rate.

(Conventional mode 1) A projection 3a is provided around a partition plate 3.
Except that the conventional battery D similar to the first embodiment was not provided.
Was prepared.

(Test) These batteries A, B, C, D
It was subjected to a cycle life test of 3 hour rate discharge in an atmosphere at 40 ° C. The life is defined as the time when the capacity of the battery reaches 80% of the initial capacity.
The operation was performed until the amount of electricity reached 20%. FIG. 7 shows the result.

FIG. 7 shows that the batteries A, B, and C of the present invention have better life performance than the conventional battery D.

Further, as a result of disassembling these batteries after their life, the batteries A, B and C showed no difference in the upper and lower electrolyte concentrations, and the life was caused by corrosion of the positive electrode grid and softening of the active material. On the other hand, in the battery D, the upper and lower electrolyte concentrations were different, the corrosion of the positive electrode grid and the softening of the active material were hardly observed, and the stratification of the electrolyte was the main cause of the life.

In this embodiment, the electrodes are arranged so as to be completely horizontal. However, even if the electrodes are arranged at a slight inclination, the projections can prevent the electrolyte solution from falling, and Can be prevented. In the first embodiment, the protrusions 3a of the partition plate 3 are provided only on the upper side. However, as in the second and third embodiments, the protrusions 3a may be provided on both the upper side and the lower side. Falling by blowing can be more completely prevented. Further, even if the battery is inverted, the electrolyte solution can be prevented from falling.

[0026]

As described above, according to the first aspect, the electrolyte does not almost completely move from the upper side to the lower side of the electrode group, the stratification of the electrolyte can be prevented, and the life performance can be improved. . The same effect can be obtained even if the battery is arranged on a slightly inclined surface.

According to the second aspect, there is no need to insert the partition plate between the electrode plates, so that the number of steps for assembling the electrode plates does not increase. Also, since the number of parts does not increase, the weight of the battery can be reduced.

According to the third aspect, the life of the stacked sealed lead-acid battery having high energy density and long life can be further extended.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing Embodiment 1 of the present invention.

FIG. 2 is a perspective view of a partition plate according to the first embodiment.

FIG. 3 is a schematic sectional view showing Embodiment 2 of the present invention.

FIG. 4 is a perspective view of a partition plate serving also as a current collector according to a second embodiment.

FIG. 5 is a schematic sectional view showing Embodiment 3 of the present invention.

FIG. 6 is a plan view showing the electrode of FIG. 5;

FIG. 7 is a graph showing the life performance of batteries A, B, and C of the present invention and conventional battery D.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Positive electrode plate 2 Negative electrode plate 3 Partition plate 1b, 1b Acid-resistant and oxidation-resistant sheet 1c, 2c Lead or lead alloy sheet 1d, 2d Through hole 1e Positive electrode active material 2e Negative electrode active material 3a Projection of partition plate

Claims (3)

[Claims] 1. A sealed lead-acid battery in which a positive electrode and a negative electrode are stacked with a separator interposed therebetween to form an electrode group, and the electrode group is arranged so that the electrode surface is horizontal. A sealed lead-acid battery, wherein a partition plate that does not allow light to pass through and has at least an upwardly protruding periphery is arranged. 2. The sealed lead-acid battery according to claim 1, wherein the partition plate also serves as a current collector for the electrode. 3. The electrode according to claim 1, wherein an acid-resistant and oxidation-resistant sheet having a large number of through-holes and a lead or lead alloy sheet are laminated, and the active material is filled in the through-holes. A sealed lead-acid battery characterized in that: