JPH0997601A - Separator for lead-acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the contact of the plane part of a plane sheet with a positive plate, and easily exhaust gas evolved by forming a straight gas exhausting path and a crooked gas exhausting path between ribs. SOLUTION: Ribs 2 are formed in a plane sheet 1 so that a straight gas exhausting path 3 which is not crooked and a crooked gas exhausting path 4 are formed in the vertical direction from the bottom to the top. The straight gas exhausting path 3 is easily exhaust gas and the crooked gas exhausting path 4 prevents the contact of the plane part 1a of the plane sheet 1 with a positive plate. The discharge performance of a battery is enhanced, the oxidation deterioration of a separator caused by the positive plate is suppressed, and the life of the battery is lengthened. The straight gas exhausting path 3 is formed in the vertical direction from the bottom to the top by the region where the rib 2 does not exist, and the crooked gas exhaust path 4 is formed next to the straight gas exhausting path 3 with the sinusoidal rib 2 arranged from the bottom to the top.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead storage battery separator in which a plurality of rows of ribs are provided on at least one surface of a flat sheet. More specifically, the present invention relates to a high-performance separator that prevents contact between the flat plate portion of the flat sheet and the positive electrode plate, can prolong the life of the battery, and can easily discharge gas generated during use of the battery.

[0002]

2. Description of the Related Art As a conventional lead-acid battery separator of this type, as shown in FIG. 4, a plurality of linear ribs 2 arranged in parallel with each other are provided on at least one surface of a flat sheet 1. , 2, a separator in which a straight gas discharge path 3 that does not bend vertically from the bottom to the top is provided, or, as shown in FIG.
There is known a separator in which a plurality of sinusoidal ribs 2 are arranged in a nested manner on at least one surface of a flat sheet 1 and a bent gas discharge path 4 is provided between these ribs 2.

[0003]

However, since the former separator has a straight gas discharge path 3 which does not bend from the bottom portion to the upper portion, it has a good gas releasing property, but the In order to prevent contact between the flat plate portion 1a of the flat sheet 1 and the positive electrode plate due to electrode plate deformation during use, it is necessary to set the distance between the ribs 2 and 2 arranged in parallel to each other to about 5 to 7 mm. Thus, when the ribs 2 and 2 are sandwiched in this way, the electrolytic solution holding space formed by the ribs 2 and 2 arranged in parallel, the flat plate portion 1a of the flat sheet 1 and the electrode plate is narrowed, and the diffusibility of the electrolytic solution is increased. Has been a cause of deterioration in battery performance. Further, since the latter separator has a plurality of sinusoidal ribs 2 arranged in a nested manner on at least one surface of the flat sheet 1, it is excellent in preventing contact between the flat plate portion 1a of the flat sheet 1 and the positive electrode plate. However, since the plurality of sinusoidal ribs 2 were arranged in a nested manner with respect to each other, the gas release property was inferior to the former separator. The present invention is intended to solve the above drawbacks of the conventional ribbed separator, prolong the service life of the battery and improve the performance, and discharge the gas generated during use of the battery and deform the electrode plate during use of the flat plate sheet. In order to prevent contact between the flat plate portion and the positive electrode plate, the present invention is intended to eliminate the drawbacks of the conventional separator by arranging and arranging ribs formed on at least one surface of the flat sheet.

[0004]

In order to solve the above problems, the present invention provides a lead-acid battery in which a plurality of ribs are provided on at least one surface of a flat sheet and a gas discharge path is formed between these ribs. In the separator, the gas discharge path includes a straight gas discharge path that does not bend in the vertical direction from the bottom to the top, and a bent gas discharge path. In this case, the linear gas discharge path is formed by a region in which there is no rib in the vertical direction from the bottom to the top, and the bent gas discharge path is adjacent to the linear gas discharge path from the bottom. It is preferably formed by a sinusoidal rib provided over the upper portion. Further, the linear gas discharge path is formed by a region in which there is no rib in the vertical direction from the bottom to the upper portion, and the bent gas discharge path is adjacent to the linear gas discharge path from the bottom to the top. It is preferably formed by a plurality of V-shaped ribs provided over the entire length. The V-shaped ribs may be provided in the same height in the horizontal direction, or may be provided in a nested shape with the heights in the horizontal direction being shifted. The lead-acid battery separator can be easily obtained by roll-molding the thermoplastic resin composition using a roll having grooves on its outer peripheral surface so that the predetermined ribs can be formed.

As described above, the separator of the present invention has ribs formed on a flat sheet so that a gas discharge path that does not bend vertically from the bottom to the top and a bent gas discharge path can be formed. The gas discharge path that does not bend in the vertical direction from the bottom to the top facilitates gas discharge, which contributes to improved battery discharge performance. By forming the sheet, it is possible to prevent contact between the flat plate portion of the flat sheet and the positive electrode plate, and suppress oxidative deterioration of the separator due to the positive electrode plate, so that the life of the battery can be extended.

[0006]

Embodiments of the present invention will now be described with reference to the drawings. (Example 1) The lead-acid battery separator of this example is shown in FIG.
As shown in FIG. 5, a sine wave rib 2 is provided on the flat sheet 1 as in the conventional separator shown in FIG. 5, and a flat plate portion 1a is provided between the ribs 2 and 2. As shown in the drawing, the lead-acid battery separator is formed by a region where the rib 2 does not exist from the bottom to the top.
A bent gas discharge formed by a straight gas discharge path 3 that does not bend vertically from the bottom to the top and a sinusoidal rib 2 provided adjacent to these straight gas discharge paths 3. It is configured with route 4.

The separator of this embodiment is a melt-kneaded product of 15 parts by weight of high-density polyethylene having a weight average molecular weight of 1,000,000, 30 parts by weight of silica powder having a specific surface area of 200 m ² / g, and 60 parts by weight of mineral oil. Extruded into a sheet using, then the sheet-shaped melt-kneaded product is formed into a sheet having ribs using a pair of forming rolls having grooves so that a desired rib shape is obtained on the outer peripheral surface of the roll, Then, the sheet is dipped in trichlorethylene to extract and remove a part of the mineral oil in the sheet, and the residual oil amount becomes 1
It is manufactured as a separator for a lead acid battery with a rib of 4% by weight.

(Embodiment 2) In the embodiment shown in FIG. 2, a flat sheet 1 is provided with V-shaped discontinuous ribs 2 and a flat plate portion 1a is provided between these ribs 2 and 2. Similar to the first embodiment, the straight gas discharge paths 3 formed by the region where the ribs 2 do not exist extend from the bottom to the top and are provided adjacent to these straight gas discharge paths 3. And a bent gas discharge path 4 formed by the V-shaped rib 2 formed. The V-shaped ribs 2 have the same horizontal height.

(Embodiment 3) The embodiment shown in FIG. 3 has the same construction as that of Embodiment 2 except that the V-shaped rib 2 is formed in a nested shape by shifting the height in the horizontal direction. In addition, Example 2 and Example 3 were also manufactured by the same manufacturing method as the lead storage battery separator of Example 1.

Next, a lead storage battery was prepared using the ribbed lead storage battery separator of the present invention of Examples 1 to 3 and the conventional lead storage battery separators 1 and 2 shown in FIGS. And the heavy load life specified in JIS D5301 were evaluated. In addition, the gas release property was visually confirmed by using a single cell battery using a transparent battery case for the gas release property generated during overcharge. The above evaluation results are shown in Table 1 below.

[0011]

[Table 1]

As is clear from Table 1, Examples 1 to 3 of the present invention are good in terms of outgassing and battery life.

[0013]

The lead-acid battery separator of the present invention is provided with ribs on a flat sheet so that a straight gas discharge path and a bent gas discharge path that do not bend vertically from the bottom to the top are formed. By forming a straight gas discharge path that does not bend vertically from the bottom to the top, it facilitates gas discharge, which contributes to improved battery discharge performance. By forming such a gas discharge path, it is possible to prevent contact between the flat plate portion of the flat sheet and the positive electrode plate, and suppress oxidative deterioration of the separator due to the positive electrode plate, so that the effect of extending the battery life is achieved. Have.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of a lead-acid battery separator of the present invention.

FIG. 2 is a plan view of another embodiment of the lead-acid battery separator of the present invention.

FIG. 3 is a plan view of still another embodiment of the lead-acid battery separator of the present invention.

FIG. 4 is a plan view of a conventional ribbed lead-acid battery separator.

FIG. 5 is a plan view of a conventional lead-acid battery separator with ribs.

[Explanation of symbols]

 1 Flat Sheet 1a Flat Plate 2 Rib 3 Straight Discharge Path 4 Bent Discharge Path

Claims (5)

[Claims] 1. A lead storage battery separator in which a plurality of rows of ribs are provided on at least one surface of a flat sheet and a gas discharge path is formed between these ribs, wherein the gas discharge path has a bottom portion in the vertical direction. A lead-acid battery separator comprising a straight gas discharge path that does not bend from the top to the top and a bent gas discharge path. 2. The straight gas discharge path is formed by a region where there is no rib in the vertical direction from the bottom to the top, and the bent gas discharge path is adjacent to the straight gas discharge path. The lead storage battery separator according to claim 1, wherein the separator is formed of a sinusoidal rib provided from the bottom to the top. 3. The straight gas discharge path is formed by a region in which there is no rib in the vertical direction from the bottom to the top, and the bent gas discharge path is adjacent to the straight gas discharge path. The lead storage battery separator according to claim 1, wherein the separator is formed by a plurality of V-shaped ribs provided from the bottom to the top. 4. The lead-acid battery separator according to claim 3, wherein the V-shaped ribs are provided at the same height in the horizontal direction. 5. The lead-acid battery separator according to claim 3, wherein the V-shaped ribs are provided in a nested shape with their horizontal heights shifted.