JPH0147856B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an electrode plate substrate formed by an inner punching method of a lead acid battery electrode plate substrate formed by a machining method from a lead or lead alloy thin plate.

Traditionally, lead-acid battery electrode plates have been manufactured using a casting method, but recently there has been a demand for maintenance-free batteries, as well as a need for lighter weight, higher performance, and longer lifespans for batteries. In place of the above-mentioned casting method, machining methods, ie, punching method and expanding method, are attracting attention, and progress is being made in the development and practical application of these methods.

The feature of this machining method is that it uses lead or lead alloy thin sheets obtained by rolling (hereinafter simply referred to as lead alloy thin sheets), which is difficult or impossible to manufacture using the casting method. In order to be able to manufacture thin substrates with a thickness of
Lead-calcium, lead-calcium-tin, and lead-calcium-aluminum alloys are mainly used. However, this type of lead alloy generally has low mechanical strength, so if the electrode plate is constructed by filling the active material of the board using the conventional punching method, and a storage battery made of this electrode plate is used, the volume of the active material will change. The positive electrode plate undergoes elongation and deformation due to corrosion or corrosion, which significantly impedes electrical contact with the active material or causes a short circuit with the negative electrode plate, resulting in a short life span. Although the reason for this cannot be elucidated in detail, it is thought to be due to the method of punching out the substrate from a lead alloy thin plate as shown in FIG. That is, 11 is a thin plate obtained by rolling a lead alloy, and arrows R and D indicate the rolling direction of the thin plate. 12 is a two-piece punched board that is integrated with the legs 13 of the board; 14 is an edge of the board; 1
5 and 16 are horizontal lattice bars of the substrate, vertical lattice bars 17 are vertical outer lattice bars, and 18 and 19 are horizontal upper lattice bars and horizontal lower lattice bars. Therefore, the horizontal lattice bars 15 and the horizontal upper and lower lattice bars 18 and 19 on the substrate are provided parallel to the rolling direction, and the vertical lattice bars 16 and the vertical outer lattice bars 1 are provided parallel to the rolling direction.
7 is provided perpendicularly to the rolling direction, and it is thought that this defect is caused by the frame ribs intersecting each other at 90 degrees.

The present invention has been made as a result of extensive research aimed at improving these drawbacks, and has resulted in the discovery of an electrode plate substrate that significantly improves the performance of storage batteries. That is, the present invention consists of a thin plate 11 made of lead or a lead alloy, the thin plate is a rolled plate, the thin plate is punched into a parallelogram lattice shape, and the outer peripheral part 32 has no punched part. Consisting of a thin plate base metal portion, the base metal portion is deformed into a wave shape in the length direction, and the lattice bars 33,
It is characterized in that the angle formed between the center lines of 34, 35, and 36 and the rolling direction of the thin plate 11 is 0° to 50°.

In the present invention, in particular, unevenness is formed in the uncoated area, and the reason for this is to correctly control the amount of active material filled into the substrate and to maintain the thickness of the electrode plate constant.

Also, the reason why the value of θ is limited to 0° to 50° in the present invention will be explained.

That is, Figure 2 shows the method of cutting out a test piece for measuring the tensile strength of a lead alloy thin plate.
1 is a lead alloy thin plate obtained by rolling, arrows R, D
indicates the rolling direction, and 21 is a test piece for the tensile test.

Therefore, the center line mn of the test piece 21 and the rolling direction R,
Let the angle between D and parallel lines p and q be θ°, and let this θ be
Various test specimens were prepared by varying the angle from 0° to 90°, and a tensile test was conducted at room temperature at a strain rate of 1.67×10 ^-3 s ^-1 to determine the yield strength (σ _0.2 )
I asked for The results are shown in Figure 3, where σ _0.2 (θ) at each θ is σ _0.2 (0) at θ=0°.
The ratio σ _0.2 θ/σ _0.2 (0) divided by the value of is plotted for each θ. As is clear from the drawing, θ
σ _0.2 (θ)/σ _0.2 (0) is almost 1 from 0° to approximately 50°, but when θ exceeds 50°, σ _0.2 (θ)/σ _0.2
(0) was observed to decrease rapidly. In other words, the yield strength decreases as θ approaches the right angle from 50° to the rolling direction. Therefore, θ is limited to 0° to 50°.

Next, examples of the present invention will be described.

EXAMPLE As shown in FIG. 4A, a rolled lead alloy thin plate having a thickness of 0.65 mm is punched out regularly in a staggered manner to form a large number of active material filling spaces 31. In addition, the openings to be formed at the outer periphery of the substrate (the shaded areas in the drawings) were not opened, and a blank portion 32 was formed by punching out a blank plate. Four lattice bars 33, 3 surrounding the active material filling space 31
4, 35, and 36 each have their center lines at an acute angle (θ) of 30° to the line segments ab and cd, which are parallel to the rolling direction (arrow R, D) of the lead alloy thin plate, and the rolling direction of the lead alloy thin plate (arrow R) , D) is the acute angle (θ) formed by
The angle is 30°. Further, the connected triangular uncoated parts 32 on the outer periphery of the top plate punched and formed in this way are bent in different directions into triangular pyramid shapes as shown in FIG. An electrode plate substrate for a storage battery of the present invention was obtained by forming irregularities. The distance (r) from peak to peak on one side of the uneven portion is approximately 10 mm, the thickness (t) of the plain portion 32 on which the uneven portion is formed is 1 mm, and the width of the frame rib is approximately 1 mm.
In the figure, reference numeral 37 denotes an electrode plate lug formed at the same time by punching. The electrode plate substrate for a storage battery obtained in this way is filled with an active material to form an electrode plate, and the filling thickness of the active material can be easily controlled by the unevenness formed on the outer periphery of the substrate. The amount can be controlled, the filling thickness can be made constant, and the active material can be prevented from falling off around the electrode plate. As in the above embodiment, in which triangular pyramid-shaped uneven parts are formed on the uncoated area of the outer periphery of the substrate, the distance between adjacent protrusions on the substrate-side surface and the slopes where the protrusions face each other becomes narrower toward the outside. , it is more effective to prevent the active material filled in the substrate from falling off at the periphery. In the above embodiment, the uncoated portions at the four corners of the substrate were cut.

Storage batteries were formed using the thus obtained substrates of the present invention and substrates formed by the conventional punching method, respectively, and the lifespan was measured according to the JIS cycle. The results are shown in Table 1.

Table 1 Product of the present invention 230 cycles Conventional product 50 cycles As detailed above, the present invention has the following effects.

(1) Since the acute angle between the center line of the lattice bar and the rolling direction of the lead alloy thin plate is set to 0° to 50°, the mechanical strength of the lattice bar is improved and the elongation deformation of the electrode plate is prevented.

(2) The outer periphery is a plain area without punching, and by forming irregularities of an arbitrary height on this blank area, the substrate is filled with an active material to obtain an electrode plate. Therefore, it is possible to easily obtain an electrode plate having a desired thickness, and the active material does not fall off from the periphery.

Therefore, since short circuits can be prevented, the life of the storage battery can be extended.

[Brief explanation of drawings]

Fig. 1 is a plan view of a storage battery electrode plate substrate made by conventional punching method, Fig. 2 is an explanatory diagram of a cut-out state of a test piece for strength testing, and Fig. 3 shows an active material filling space in a lead alloy thin plate in the rolling direction. FIG. 4, which is a curve diagram showing the relationship between the angle change of the lattice crosspieces formed and the yield strength, shows the substrate for the storage battery electrode plate of the present invention.
is a plan view, and B is a side view. 11...Lead alloy thin plate, 12...Substrate, 13...
Legs, 14...ears, 15...horizontal lattice bars, 16...
Vertical lattice bar, 17... Vertical outer lattice bar, 18... Horizontal upper lattice bar, 19... Horizontal lower lattice bar, 21... Test piece, 31, 31', 31''... Active material filling space part,
32, 32'... Convex portion, 33... Concave portion, 34, 3
5, 36, 37... Lattice crosspiece.

Claims (1)

[Claims] 1. Consists of a thin plate 11 of lead or lead alloy, the thin plate is a rolled plate, the thin plate is punched into a parallelogram lattice shape, and the outer peripheral portion 32 is punched. The base metal part is a thin plate having no parts, and the base metal part is deformed into a wave shape in the length direction, and the center line of the lattice bars 33, 34, 35, 36 and the rolling direction of the thin plate 11 are aligned. A lead-acid battery electrode plate substrate characterized in that the angle formed is between 0° and 50°.