JPS6324569A - Lead storage battery - Google Patents

Abstract

PURPOSE:To maintain the fastening force for a long time and to improve the service life of a lead storage battery, by furnishing rib plates opposing to a battery jar at both sides of an electrode group, and fastening both the electrode group and the rib plates in about a circular form with heat-weldable bands with a specific breaking strength. CONSTITUTION:At both sides of an electrode group consisting of positive electrode plates 1, separators 3, and negative electrode plates 2, rib plates 4 made of vinyl chloride or the like are contacted opposing to a battery jar 6. Then the whole electrode group including the rib plates 4 are pressed hard, and when the pressure reaches to a specific value, they are fastened in about a circular form by heat-weldable bands 5 made of a high acid-proof polyolefine type resin or the like. In this case, the breaking strength of the bands 5 is regulated larger than 0.5 X S kg (S = electrode plate area cm<2>). After that, they are housed in the battery jar 6 to compose a lead storage battery. Therefore, the fastening force to the electrode group is maintained well for a long time, and the service life property can be improved extensively.

Description

[Detailed description of the invention] Industrial applications The present invention relates to improvements in lead-acid batteries.

Conventional technology and its problems As is well known, the life performance of lead-acid batteries is determined by applying moderately high pressure from both sides to the electrode group, which is made up of a positive electrode plate, a negative electrode plate, a separator placed between the two electrode plates, and a glass mat. and significantly improved.

In conventional assembly, a product with a pre-calculated extremely detailed thickness is inserted into a container that is designed to be slightly narrower, or
Alternatively, acid-resistant synthetic resin or valve fiber boards called occlusion boards, spacers made of salt water vinyl, etc. are arranged on both sides,
'wA type designed to be inserted into the L tank and to obtain a predetermined tightening force is used.

Another method of applying pressure to the electrode group is to use heat-shrinkable tape to hold the electrode group with the spacer in contact with it.
A method of overturning has been proposed. However, in this case, the compression force required to maintain the life of the lead-acid battery cannot be obtained. In addition, it had the disadvantage of poor creep resistance and a large drop in polar group compression force during use. The rough heat shrink tape is
Since the breaking strength per unit area is low, it is necessary to wrap it so as to cover the entire detailed surface of the shuttle plate. This hinders the use of the electrolyte around the electrode group, causing a drawback in which it is difficult for liquid type lead-acid batteries to achieve sufficient capacity.

By the way, the ml that maintains the polar group with high tension until the end of its life must be strong. That is, a material with high rigidity and thickness, such as an ebonite battery case or an AS resin kaemone, is used. As a result, the battery case becomes large in volume and weight, resulting in high manufacturing costs and increasing the total cost of the entire battery.

A method using band binding has also been proposed as a method of applying compressive force to the pole group. However, in order to maintain the tension of the electrode plate group, the breaking strength of the band has not been sufficiently calculated based on the current situation. In order to maintain the electrode group consisting of the positive and negative electrode plates, seven-layer pallet, and glass mat with the same tension as at the beginning until the end of the battery's life, the breaking strength of the band is determined by the strong force of the electrode group, which is the original purpose. The design must take into consideration elongation due to binding and creep of the band material, as well as volumetric expansion due to charging and discharging of the positive electrode active material.

OBJECTS OF THE INVENTION The present invention has been made in view of the above-mentioned conventional drawbacks, and an object of the present invention is to provide an inexpensive lead-acid battery with significantly improved life performance.

Structure of the Invention In order to achieve the above object, the present invention provides one on both sides of the pole group.
! A rib plate facing the tank is provided, and a heat-weldable band is used to bind the plate into a substantially circular shape, and the breaking strength of the band is 5×Skg (S: electrode plate area (Cd')).
) It is a lead-acid battery characterized by being larger.

Example DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be explained below using figures.

FIG. 1 is a perspective view showing the inside of the lead-acid battery of the present invention. 1 is a positive electrode plate group, 2 is a negative plate group, 3 is a seven pallet plate and a glass mat, 4 is a rib plate, 5 is a band, and 6 is a battery case.

PVC rib plates are placed on both sides of an electrode group consisting of a positive electrode plate, a separator, a glass mat, and a negative electrode plate. The rib plate and the pole group are tied together with a band that can be heat welded. A band made of polypropylene or the like made of a polyolefin resin with excellent acid resistance is used. Pressure is applied to this band from both end faces of the pole group, the band is hung, and both ends of the band are overlapped and bonded by heat welding. The configuration is as above 2
A 20 Ah battery was made, and the breaking strength of the band was A.
r B t Ot D t E, and 6 g of an electrolytic solution (dilute sulfuric acid) having a specific gravity of 1.26 was injected, and the life characteristics and changes in the thickness of the electrode plate group during the life were investigated. The results are shown in Table 1.

As is clear from the above results in Table 1, when the band breaking strength of the present invention is greater than 0.58, the life characteristics are extremely excellent.

The reason for this is, as seen in the change in pole group thickness in Table 1.
It is related to thickness change. In other words, even if high pressure is applied to the initial electrode group from both end faces and a predetermined tension is set, the volume expansion of the active material due to charging and discharging and the tension of the separator and glass mat placed between the electrode plates This seems to be due to the effects of repulsive force and the inherent elongation of polypropylene, which is the material of the band.

It should be noted that if the entire pole group including the rib plate is formed into a substantially circular shape, the tightening effect will be high and loosening will be suppressed. Also, the number of straps can be either one or several folds.

The battery of the present invention has no pressure applied to the wall of the battery case, so 1! The frame material may have low rigidity and the thickness of the battery case may be thin. Therefore, IEf19, which is made of inexpensive materials such as polyethylene and polypropylene and is reduced in cost, can be used, so the total cost of the entire battery is reduced.

Effects of the Invention As described above, the present invention can provide an inexpensive lead-acid battery with significantly improved life performance, and therefore has extremely great industrial value.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the inside of a 1FL storage pond, which is an embodiment of the present invention.

Claims (1)

[Claims] Rib plates facing the battery case are provided on both sides of the pole group, and both are bound together in a shape approximately approximated by a circle using a heat-weldable band, and the breaking strength of the band is 0.5×Skg (S: pole). A lead-acid battery characterized by having a larger plate area (cm^2).