JPH0917425A - Paste pole plate for alkaline battery and its manufacture - Google Patents

Abstract

PURPOSE: To provide a paste pole plate for alkaline storage batteries which brings about increased mechanical strength of a boundary between a pole plate main part filled with an active material and a compressed surface area plate part for attaching a collector plate thereto and improved electric conductivity and discharging performance for a pole plate. CONSTITUTION: An inner area plate part 2a, having a larger surface area than its surface area, is attached by pressure to, a surface area compressed plate part 1b of a pole plate 1 for attaching a collector plate thereto. And a edge area plate part 2b thereof is attached by pressure to a part of a pole plate main plate part 1a filled with an active material and a base part 3a of the collector plate 3 is welded to the reinforcing plate 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paste type electrode plate for an alkaline battery such as a nickel-cadmium battery, a nickel-iron battery, a nickel-zinc battery and a nickel-hydrogen battery, and a method for producing the same.

[0002]

2. Description of the Related Art As a conventional electrode plate for an alkaline battery, a sintering type having a long life and excellent rapid charge / discharge characteristics has been mainly adopted. However, in recent years, there has been a demand for higher capacity batteries, and in order to meet this demand, the paste type, which enables high-density filling of active materials, is becoming the mainstream. As a paste type electrode plate, a two-dimensional porous substrate such as a net or a porous sheet coated with a paste active material composed of an active material, a binder, a conductive agent, etc., and a three-dimensional porous material such as foam metal or felt metal. There is a substrate filled with the paste active material. This method of filling the three-dimensional porous substrate with the paste active material is superior to the method of coating the two-dimensional porous substrate with the paste active material in terms of the binding property of the active material and the good conductivity of the electrode plate. Is used for the Ni electrode or the like to which the active material paste is difficult to apply. When attaching the current collector to the paste-type electrode plate, the paste-type electrode plate is used to improve the mechanical strength and conductivity of the area plate portion for attaching the current collector plate. It is publicly known that pressure is applied to form a surface area compression plate portion for attaching a current collector plate, and a current collector plate is welded to and attached to this. An example thereof is shown in FIGS. 12 and 13 of the accompanying drawings. In the drawings, A represents a paste type electrode plate for an alkaline battery, and the electrode plate A uses a sponge-like metal porous substrate having a porosity of 95 to 98%, and pastes in the innumerable micropores that are three-dimensionally connected. An electrode plate main plate part a1 which is filled with an active material and whose thickness is adjusted appropriately, and a current collecting plate mounting surface of a predetermined rectangular surface area for pressing a current collecting plate mounting area plate part at its corners. It is formed on the area compression plate part a2,
The base portion of a rectangular current collector plate b such as a nickel plate is overlapped and spot-welded on the current collector plate mounting area compression plate portion a2. Thus, the current collecting plate b is configured to favorably extract electricity from the electrode plate main plate part a2 via the current collecting plate mounting surface area compression plate part a2 having improved mechanical strength and conductivity. It is the one. As an improved version of this, in JP-A-53-25839, in order to improve the strength of the surface area compression plate portion a2 for attaching the current collector plate of the illustrated paste type electrode plate A, the area area compression plate is improved. A conductive powder, a conductive porous body, or both, or a conductive wire is arranged as a reinforcing member in the portion a2, and pressure is applied to increase the thickness of the current collector plate mounting surface area compression plate portion a2. An improved type of paste type electrode plate is proposed in which the mechanical strength of the plate portion a2 is increased and the current collector plate b is welded to its reinforcing material.

[0003]

However, both the conventional paste type electrode plate A and the improved type shown in the above figures have a porosity in which the surface area compression plate portion for mounting the current collector plate and the active material are filled. It was confirmed that the strength of the boundary portion c with the electrode plate main plate portion a1 having a large value is insufficient and there is a defect that breakage easily occurs at the boundary portion c.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks of the past type electrode plate, increases the mechanical strength, and improves the conductivity between the electrode plate main plate portion and the current collector plate. Improvement and
Furthermore, the present invention provides a paste-type electrode plate for an alkaline battery, which brings about an improvement in discharge performance, which comprises an electrode plate main plate portion filled with a paste active material and a current-collecting plate mounting area compression plate portion. A reinforcing plate is attached to at least one surface of the surface area compression plate portion for attaching the current collector plate, and the inner surface area plate portion is polymerized and pressure-bonded to the surface area compression plate portion for attaching the current collector plate. A portion of the electrode plate main plate portion beyond the boundary between the current plate mounting surface compression plate portion and the electrode plate main plate portion is polymerized and pressure-bonded, and the inner surface region plate portion of the reinforcing plate or the collector plate The present invention is characterized in that the base portion of the current collector plate is welded to the surface compression plate portion for mounting the current plate. Further, the present invention provides a method for manufacturing the electrode plate of the present invention having the above-mentioned various characteristics, wherein (a) a predetermined porous substrate for an electrode plate having innumerable three-dimensionally continuous micropores is provided. Polymerizing a reinforcing porous plate having a surface area larger than the surface area and having innumerable three-dimensionally continuous micropores on at least one surface of the surface plate for mounting the current collector plate, (b) The current collecting plate mounting surface area plate portion of the electrode plate porous substrate and the inner surface area plate portion of the reinforcing porous plate which is superposed with the current collecting plate mounting pressure plate, and the current collector plate mounting surface area compression plate portion, Forming on the inner surface area compression plate portion crimped thereto, (c)
Pressurizing the marginal area plate portion of the reinforcing porous plate to form the marginal area compression plate portion crimped to a part of the main plate portion, (d)
Filling the main plate portion with a paste active material, (e) pressing the main porous substrate portion filled with the active material to form an electrode plate main plate portion holding the active material, (f) It is characterized in that the inner surface compression plate portion of the reinforcing plate or the surface compression plate portion for attaching the current collection plate is welded to the base portion of the current collection plate.

[0005]

The reinforcing plate not only increases the strength of the current collector plate-attaching compression plate portion itself of the electrode plate, but its peripheral region compression plate portion exceeds the current collector plate attaching compression plate portion. Since it is pressure-bonded to the main plate of the electrode plate on the outer periphery of the electrode plate, a stable and robust electrode plate with increased rupture strength at these boundaries can be obtained, and at the same time, the electrode plate main body via the peripheral region compression plate part The electrical conductivity from the plate portion to the current collector is improved and the discharge performance is increased.

In this case, the peripheral area plate portion of the reinforcing plate is bited into and crimped to a part of the electrode plate main plate portion, and the outer periphery thereof is flush with the electrode plate main plate portion or a position lower than the same. When the inner surface area plate portion is positioned lower than the electrode plate main plate portion to form a concave space on the outer side thereof, and when the base portion of the current collector plate is housed in the concave space and welded, the reinforcement is applied. The outer surface of the plate and the base portion of the current collector plate does not protrude from the electrode plate surface, and therefore, when a separator is polymerized on this, damage to the separator and a short circuit with a heteropolar plate superposed on the separator can be prevented, and a good electrode is obtained. The production efficiency of a battery capable of assembling the plate group is improved.

Also, the same one as a three-dimensional porous substrate is used as the reinforcing plate, and the density of the peripheral region compression plate portion of the reinforcing plate composed of the reinforcing plate is smaller than that of the inner surface region compression plate portion. By forming the electrode plate main plate portion to have a density higher than that of the electrode plate main plate portion, the strength of connection between the reinforcing plate and the electrode plate main plate portion is large, and the electrode plate main plate portion to the current collector plate mounting area compression portion is formed. Serves as a passageway with increased electricity extraction performance.

According to the method of manufacturing the above-mentioned electrode plate of the present invention,
(A) Surface area for attaching collector plate of the three-dimensional porous substrate for polar plate A three-dimensional reinforcing porous plate having a larger surface area on at least one surface of the plate portion is used for collecting current on the porous substrate for polar plate. Superposition on the plate mounting surface area plate portion at the inner area plate portion, and (b) in the current collecting plate mounting surface area compression plate portion of the porous plate for the electrode plate and the reinforcing porous plate overlapping with the compression plate portion. A compression plate for mounting a current collector plate having improved mechanical strength by pressurizing the area plate part to form a surface area compression plate part for mounting the current collector plate and an inner surface area compression plate part crimped thereto. And (c) pressurizing the marginal area plate portion of the reinforcing porous plate to form a marginal area compression plate portion that is crimped to a part of the electrode plate main plate portion, (d) Filling the main plate portion with a paste active material, (e) pressing the main plate portion to form an electrode main plate holding the active material, (f) compressing the inner surface of the reinforcing plate By welding the base portion of the current collector plate to the portion, the electrical and mechanical connection of the reinforcing plate to the electrode plate main plate portion through the peripheral region compression plate portion is provided, and the electrode plate main plate Although a paste type electrode plate with improved extraction of electricity from the current collector to the current collector can be obtained, it is also possible to weld the base of the current collector to the current collector mounting surface area compression plate. Good electrical and mechanical connections are obtained.

In this case, a predetermined current collector plate mounting area plate portion of the porous substrate for polar plate is pressed from at least one side and is positioned lower than at least one outer surface of the porous substrate for polar plate. It is formed on a surface compression plate part for mounting a current collector plate having a concave space on the outside, and the inner surface area plate part of the reinforcing porous plate is pressed to be accommodated in the concave space and for mounting the current collector plate. It is formed on the inner surface area compression plate portion that is crimped to the surface area compression plate portion, and the marginal area plate portion is pressed to bite into the part of the electrode plate main plate portion and press-bonded, and the electrode plate main body on the outer periphery thereof is formed. The plate is formed on the same plane as the plate part or on a lower peripheral edge compression plate part, and the base part of the current collector plate is welded to the reinforcing plate housed in the concave space so that the reinforcing plate and the collector plate are separated from the electrode plate. A flat electrode plate in which the electrode plate does not protrude can be obtained, and a plate group without damage to the separator and short circuit with the electrode plate of different polarity can be obtained.

[0010]

Next, an embodiment of the present invention will be described with reference to the accompanying drawings. 1 and 2, reference numeral 1 denotes a paste type electrode plate for an alkaline battery according to an embodiment of the present invention. The electrode plate 1
Is a paste active material, for example, a positive electrode active material powder such as nickel hydroxide, in a myriad of three-dimensionally continuous micropores in a metal foam porous substrate such as nickel, preferably cobalt oxide. Electrode plate main plate 1a and its porous substrate, which are filled with a paste active material prepared by kneading with an additive material such as CMC and an aqueous solution of a thickener such as CMC, and whose thickness is adjusted by pressurization to hold the active material. For example, a high-density current collector plate mounting surface area compression plate portion 1b whose corners are pressed into a predetermined square surface area without being filled with the active material. The reinforcing plate 2 is pressure-bonded to the outer surface of the region compression plate portion 1b to increase the mechanical strength of the current collecting plate mounting surface region compression plate portion 1b, and the outer surface of the reinforcing plate 2 has a rectangular shape such as a nickel plate. The base 3a of the electric plate 3 is spot-welded. The above basic structure is the same as that of the conventional electrode plate.

That is, according to the present invention, as the reinforcing plate 2, for example, a nickel plate having a desired thickness having a surface area larger than the surface area of the surface plate compression plate portion 1b for mounting the current collector plate or other rectangular cubic. Using an original porous metal plate, its inner area plate portion 2a is superposed and pressure bonded to the current collector plate mounting surface area compression plate portion 1b, and the margin area plate portion 2b consisting of two sides thereof is used for mounting the current collector plate. The area of the electrode plate main plate portion 1b and the electrode plate main plate portion 1a are cross-bonded to a part of the electrode plate main plate portion along the two sides of the outer periphery of the compression plate portion 1b beyond the boundary 1c, and the reinforcement is performed. The base portion 3a of the current collector plate 3 is welded to the inner surface area plate portion 2a of the plate 2 to form the paste type electrode plate of the present invention. Thus, the reinforcing plate 2 is firmly attached to the electrode plate 1 by straddling the boundary portion 1c having a relatively low strength, to the electrode plate main plate portion 1a and the collector plate mounting surface area compression plate portion 1b. Since it is bound to, the breaking strength of the boundary portion 1c increases,
At the same time as providing the electrode plate 1 which is stable and robust, the edge area plate portion 2b is firmly mechanically and electrically connected to the electrode plate main plate portion 1a, so that the conductivity through this increases. However, it is possible to easily and increase the extraction of electricity from the electrode plate main plate portion 1a to the current collector plate 3, and to improve the battery performance such as rapid discharge performance.

In this case, the reinforcing plate 2 shown in the figure is made of a foam metal having the same material and the same porosity as the porous substrate for polar plates, and preferably has the same thickness as the porous substrate for polar plates in general. The reinforcing three-dimensional porous plate is used, and the reinforcing porous substrate is polymerized in a state in which the two vertical edges are aligned with the vertical and horizontal edges of the corner portion, and the surface area compression plate for mounting the current collector plate. The inner surface compression plate portion 2a is largely pressed by pressurizing the inner surface compression plate portion 2a overlapping the portion 1b.
The edge area plate portion 2b is formed in the inner area face plate portion 2a.
It is preferable to form the edge area compression plate portion 2b by compressing with a pressure smaller than the pressure for applying pressure to the peripheral area compression plate portion 2b that is pressed into a part of the main plate portion of the porous substrate for an electrode plate and pressure-bonded. As a result, the superposed pressure-bonding surfaces of the reinforcing plate 2, the compression plate portion 1b for attaching the current collector plate of the electrode plate 1 and a part of the electrode plate main plate portion 1a on the outer periphery of the reinforcing plate 2 are embedded in each other. , The mutual bond is firmly obtained. On the other hand, the peripheral area compression plate portion 2b of the reinforcing plate 2
Since the density of is smaller than the density of the electrode plate main plate portion 1a for good retention of the filled active material, the rupture strength of the boundary portion between the peripheral region compression plate portion 2b and the electrode plate main plate portion 1a on the outer periphery thereof. Are large and have good mutual binding properties and good conductivity.

As shown in FIG. 2, at least one surface of the current collector mounting compression plate portion 1b is positioned lower than at least one surface of the electrode plate main plate portion 1a, and a concave space 4 is formed outside thereof. , The inner surface area plate portion 2a of the reinforcing plate 2 is crimped to the current collector plate mounting compression plate portion 1b in a state of being housed in the concave surface space 4, and the concave surface space 4 on the inner surface area plate portion 2a. The base portion 3a of the current collector plate 3 is housed inside and welded to the inner surface area plate portion 2a, and the outer surface of the marginal area plate portion 2b of the reinforcing plate 2 is further surrounded by the outer electrode plate main plate portion 1a. Of the electrode plate main plate portion 1a so as to be positioned on the same surface as or lower than the outer surface of the negative electrode plate, the negative electrode plate is laminated on the electrode plate 1 via a separator. In the case of assembling the electrode plate group by applying a separator to the flat surface of the electrode plate 1, The edge plate portion 2b of the strong plate 2 and the base portion 3a of the current collector plate 3 project outward beyond the surface of the electrode plate main plate portion 1a, so that the separator is damaged and a short circuit with the negative electrode plate occurs. To be prevented.

Next, one example of the method for manufacturing the above-mentioned paste type electrode plate of the present invention will be described with reference to FIGS. As shown in FIG. 3 and FIG. 4, first, a rectangular three-dimensional porous plate for polar plates made of nickel foam metal having a predetermined thickness of a long rectangular shape for polar plates having a porosity of 95 to 98%. A predetermined portion of the board 1 ′, for example, a rectangular surface area of a predetermined area whose one corner portion is indicated by an imaginary line is attached to the upper surface of the rectangular current collector plate mounting area plate portion 1 ′ from the predetermined square surface area S. The reinforcing porous plate 2'having a similar rectangular surface area with a large surface area is placed with its two edges aligned with the two edges of the corners of its lower surface, and its inner surface plate The portion 2'a is overlapped with the surface area S of the current collector plate mounting surface area plate portion 1'b, and the margin area plate portion 2'b consisting of two sides thereof is formed into the current collector plate mounting surface area. Along the perimeter of the two sides of S,
The main plate portion 1'a is placed so as to be superposed on a part of the main plate portion 1'a. As the reinforcing porous plate 2 ', a porous substrate for polar plate 1'
The same material, porosity, and thickness were used.

Then, the inner surface plate 2'a of the reinforcing porous plate 2'is pressed from above with a large pressure, for example, 1 ton /
The current collecting plate mounting surface area plate portion 1'b of the electrode porous plate 1'and the inner surface surface plate portion 2'a of the reinforcing porous plate 2'that are polymerized by a pressure of cm ² Of the current collector plate 1b (porosity 36%) with increased mechanical strength deviated to one side as shown in FIG. 5 and the reinforcing plate 2 crimped on the upper surface thereof. The inner surface area compression plate portion 2a (porosity 36%) was formed. In this case, the surface compression plate 1b for mounting the current collector plate is located below the upper surface of the main plate portion 1'a of the porous substrate 1'for electrode plate by the pressure compression processing described above, and the upper side thereof. A concave space 4 is formed in the inner surface area compression plate portion 2a of the reinforcing porous plate 2'and the compression plate 1b is superposed and pressure-bonded.

Next, as shown in FIG. 6, the main plate portion 1'a of the electrode plate porous substrate 1'is pressed by a roller press to adjust its thickness, and at the same time, the reinforcing plate 2 '. Of the peripheral area plate portion 2'b of the base plate portion 1'a is pressed into the main plate portion 1'a prepared to have a predetermined thickness, and the outer surface of the main plate portion 1'a has an outer surface.
Edge region compression plate portion 2b crimped so as to be flush with
Formed. (See FIG. 6).

Next, the active material is filled in the main plate portion 1'a of the porous substrate for electrode plate 1'thickness thus obtained, which has been adjusted, through a paste active material filling machine, and then, After heating and drying, the thickness was further adjusted by a roll pressing machine to form the electrode plate main plate portion 1a having a predetermined thickness. Thus,
In this step, the electrode plate 1 in which the positive electrode active material is closely held in the micropores inside the electrode plate main plate portion 1a and which is filled with high density
Is obtained. (See FIG. 7). As the paste active material, for example, nickel hydroxide powder is mainly used, and a small amount of nickel powder as a conductive material, metal powder such as cobalt,
A mixture prepared by mixing a small amount of a thickener such as CMC and water and kneading is used.

Next, the electrode plate 1 shown in FIG. 7 thus obtained
1 and 2, the inner surface area compression plate portion 2a of the reinforcing plate 2 is spot-welded to a substrate 3a of a rectangular current collector plate 3 having a predetermined thickness and shape such as a nickel plate. The paste type electrode plate for alkaline storage batteries of the present invention can be obtained.

Thus, the reinforcing plate 2 has the inner surface area compression plate portion 2a, and the current area plate mounting surface area compression plate portion 1b of the electrode plate 1.
Not only increasing the mechanical strength of the plate, but also compressing the marginal area compression plate portion 2b into the electrode plate main plate portion 1a.
Since they are firmly connected, as described above, the boundary portion 1 between the electrode plate main plate portion 1a and the current collector plate mounting compression plate portion 1b.
At the same time as increasing the breaking strength of c,
It is possible to increase conductivity between the electrode plate main plate portion 1a and the current collector plate 3, facilitate extraction of electricity to the current collector plate 3, and improve discharge performance such as rapid discharge.

FIG. 8 shows another embodiment of the paste type electrode plate 1 of the present invention. A reinforcing plate 2 is provided on both surfaces of the electrode plate 1 by polymerization and pressure bonding. That is, in the electrode plate 1, the surface plate compression plate portion 1b for mounting the current collector plate is located at the center of the thickness of the electrode plate main plate portion 1a, that is, the electrode plate main plate portion 1a.
It is positioned lower than both outer surfaces of a so that concave spaces 4 and 4 are formed on both outer sides thereof, and both surfaces thereof are accommodated in the inner space compression plate portion 2a of the reinforcing plate 2 in the concave space 4. In addition, the peripheral area compression plate portion 2b is formed so as to be flush with the inner surface area compression plate portion 2a on a part of the electrode plate main plate portion 1a on the same plane. Thus, since the electrode plate 1 is provided with the reinforcing plates 2 and 2 on both sides thereof as described above, the boundary portion 1c between the electrode plate main plate portion 1a and the current collector plate mounting compression plate portion 1b is formed. The electrode plate 1 has further increased resistance to breakage. Then, either one of the reinforcing plates 2 and 2 is selected, and the base portion 3a of the collector plate 3 is superposed on the reinforcing plate 2 and 2 in the concave space 4 and spot welded.

FIG. 9 and FIG. 10 show a method of manufacturing the electrode plate of the above modification, and as shown in FIG. 9, the surface area plate portion 1 for attaching the current collector plate of the three-dimensional porous substrate 1'for electrode plate. A reinforcing porous plate 2'having a larger surface area and having the same material and the same thickness is superposed on the upper and lower surfaces of ′ b, and pressure is applied from both sides with a pressure of 1 ton / cm ² to form concave spaces on both outer surfaces. As 4 and 4 are molded,
At the same time as forming the surface area compression plate portion 1b for mounting the current collector plate at a position substantially in the center of the thickness of the main plate portion of the electrode plate porous substrate 1 ',
The inner surface compression plates 2a, 2a of the reinforcing porous plate are polymerized and pressure-bonded on both sides thereof, and thereafter, pressure is applied to adjust the thickness of the main plate, and at the same time, the reinforcing porous plate 2 is pressed. The peripheral area plate portion of ‘′ is pressed at about 0.5 ton / cm ² to form the peripheral area compression plate portion 2b which is pressed into a part of the main plate portion and press-bonded, and then the paste active material is filled. After heating and drying,
Next, it is possible to manufacture the electrode plate 1 having the electrode plate main plate portion 1a shown in FIG. Next, by welding the base portion 3a of the current collector plate 3 to the inner surface compression plate portion 2a of either one of the reinforcing plates 2 and 2 superposed and pressure-bonded on both sides of the electrode plate 1, as shown in FIG. The electrode plate 1 with the current collector plate 3 is obtained.

The electrode plate 1 thus obtained also has the maximum density of the surface area compression plate portion 1b for mounting the current collector plate and the inner area surface compression plate portion 2b as in the case of the electrode plate 1 of the previous embodiment. And the density of the marginal area is smaller than the density of the inner area face plate portion 2b,
It is configured to have a density higher than that of the electrode plate main plate portion 1a.

Next, a more specific embodiment of the present invention will be described in comparison with a conventional example. Example 1 Length 150 mm, Width 75 mm, Thickness 1.6 mm, Porosity 9
On the upper surface of one corner of 6% nickel foam porous substrate for polar plate, a nickel porous foam reinforcing plate having 13 mm length, 23 mm width, 1.6 mm thickness, and 96% porosity was prepared. 10 mm in the vertical direction of the reinforcing plate on the upper surface of the area plate part for attaching a current collector having a surface area of 10 mm in length and 20 mm in width of the corner portion of
The inner surface area plate parts having the same surface area of m and 20 mm in width are placed so as to overlap with each other, and these overlapped plate parts are placed at 1 ton / cm ²
Pressurize the surface plate for mounting the current collector plate with 0.2
mm compression plate portion, and at the same time when the inner surface area plate portion of the reinforcing plate is compression formed to a 0.2 mm compression plate portion,
The opposing surfaces of the compression plate portions are pressed against each other to form a laminated plate portion that is firmly bonded to each other, and the upper surface of the laminated plate is higher than the upper surface of the main plate portion of the porous plate for polar plates. It was located at a low position and formed a concave space above it. Next, the main plate portion of the porous substrate for polar plate was pressed to prepare a thickness of 1.40 mm, and at the same time, the peripheral edge plate portion of the reinforcing porous plate was
A peripheral region compression plate portion was formed by pressing and press-fitting a part of the main plate portion for the electrode plate on the outer periphery of the surface area compression plate portion for attaching the current collector plate to the same plane. Next, the main plate portion is mainly composed of nickel hydroxide powder, and a paste active material prepared by kneading a mixture of metallic nickel powder and cobalt oxide powder together with CMC and water is filled in, and then dried by heating. Then, the thickness was adjusted to 0.7 mm with a roll press and the filled active material was firmly held. Next, spot welding is performed on the inner surface area compression plate portion of the reinforcing plate while the base portion of the current collecting plate made of a nickel plate having a length of 50 mm, a width of 20 mm and a thickness of 0.2 mm is accommodated in the concave space. The paste type nickel electrode plate of the present invention shown in FIGS. 1 and 2 was obtained. Example 2 The same size, porosity, and material as used in Example 1 are used for the electrode porous plate. The plates were polymerized, and as in Example 1, the corners of the porous substrate for polar plates were 10 m long.
m, a surface plate for mounting a collector plate having a surface area of 20 mm, and the reinforcing plate superposed on the plate portion of 10 mm in length and 20 m in width
The inner surface area plate portion having the same surface area of m is 1 ton / cm.
Pressurizing with a pressing force of ^2, the surface area plate portion for mounting the current collector plate to 0.
The inner surface area plate portion of the reinforcing plate is formed on both sides of the compression plate portion of 2 mm to form the compression plate portion of 0.2 mm, and the three-layer superposed compression plate portions are pressure-bonded between the opposing surfaces. To form a laminated plate portion that is tightly bound to each other, and at the same time, the upper and lower surfaces of the laminated plate portion are positioned lower than the upper and lower surfaces of the main plate portion of the porous substrate for polar plates. A concave space was formed on both outer sides of the lever. Next, the main plate portion of the porous plate for an electrode plate is pressed to prepare a thickness of 1.40 mm, and at the same time, the peripheral edge plate portions of the reinforcing porous plate on the upper and lower surfaces thereof are respectively pressed to collect the gas. A marginal area compression plate portion was formed on a part of the main plate portion on the outer periphery of the surface area compression plate portion for mounting the electric plate, which was bite and crimped to be flush with the main plate portion. Next, in the same manner as in Example 1, the same paste active material was filled in the main plate portion of the porous substrate for polar plates provided with the reinforcing plates on both sides, heated and dried, and then 0.7 mm by a roll press machine. The thickness was adjusted and formed on the main plate of the electrode plate that firmly held the filled active material. next,
Similar to the first embodiment, the inner surface area compression plate portion of the one reinforcing plate was spot-welded with the base portion of the same current collector plate as in the first embodiment accommodated in the concave space, and the result is shown in FIG. The paste type nickel electrode plate of the present invention shown below was obtained. Conventional Example The same size, porosity, and material as those used in Example 1 are set in a corner area of a porous substrate for a polar plate having a predetermined surface area, that is, a length of 10 mm,
1t of surface plate for current collector mounting with a surface area of 20mm
The pressure was applied at a pressure of on / cm ² to form a 0.2 mm-thick current collector plate-attaching area compression plate portion. Next, the main plate portion of this porous substrate for polar plates was filled with the same paste active material as in Example 1, heated and dried, and then adjusted to a thickness of 0.7 mm by a roll press machine, and the filled active material was solidified. It was formed on the main plate portion of the held electrode plate. Next, the current-collecting plate mounting surface area compression plate portion was spot-welded with the base portion of the same current-collecting plate as that of Example 1 accommodated in the concave space formed on the outside thereof to perform conventional paste-type nickel. I got a plate.

A tensile strength test and a bending strength test were performed on the respective electrode plates of Examples 1 and 2 and the conventional example described above.
It was conducted in accordance with IS B 7771 and JIS Z 2248, and the presence or absence of breakage at the boundary between the electrode plate main plate portion and the current collector plate mounting area compression plate portion of each electrode plate was examined. As a result, the electrode plate of the conventional example was broken at a tensile force of 10.7 kg and a bending load of 127 g. The electrode plates of Examples 1 and 2 did not break, and it was confirmed that the reinforcing plate improved the mechanical strength of the boundary portion. By the way, the electrode plate of Example 1 has a larger tensile force of 13.6 kg and a larger bending load of 440 g,
No rupture occurred at the boundary portion, and rupture occurred at the boundary portion between the peripheral area plate portion of the reinforcing plate and the electrode plate main plate portion on the outer periphery thereof. Further, since the electrode plate of Example 2 is provided with the above-mentioned reinforcing plates on both sides of the plate portion for attaching the current collector plate of the electrode plate and the vicinity thereof, the electrode plate of Example 1 is further provided with the above-mentioned boundary portion. Breaking is also prevented, and even greater tensile force 16.8 kg and bending load 56
At 0 g, breakage occurred in the electrode plate main plate portion, that is, the active material filled portion.

Further, a hydrogen-absorbing alloy electrode plate as a negative electrode was laminated on each electrode plate of Examples 1 and 2 and the conventional example as a negative electrode by a conventional method to prepare a 100 AH class nickel-hydrogen battery, and discharge was performed at each discharge rate. A performance test was conducted. The test results are shown in FIG. As is clear from the figure, by using the reinforcing plate of the present invention, when the electrode plates of Examples 1 and 2 were used, the battery capacity was increased, especially when the electrode plates of the conventional example were used. Discharge characteristics at each discharge rate,
In particular, it has been found that the rapid discharge characteristics are increased. It is considered that this is because the reinforcing plate is strongly connected to the electrode plate main plate portion at the peripheral area plate portion, so that the conductivity from the electrode plate to the current collector plate is increased.

Further, processing from the active material filling step of manufacturing the electrode plates of Examples 1 and 2 and the conventional example to the battery assembly,
The yield of battery production after transportation was 95% in the conventional example, but was 100% in Examples 1 and 2, and the production loss of the battery was eliminated. Further, in the electrode plate of the conventional example, about 10% of the batteries produced had remarkably poor rapid discharge performance in the production of the batteries, but the batteries using Examples 1 and 2 did not.

As the three-dimensional porous substrate for polar plate and the reinforcing porous plate used in the present invention, felt metal made of metal fiber such as nickel may be used instead of foam metal. Further, the electrode plate can be applied not only to the positive electrode plate but also to a negative electrode plate filled with a negative electrode active material paste such as a hydrogen storage alloy. Further, as the reinforcing plate, a non-perforated metal plate such as a thin nickel plate that can be bent by pressure can be used. Further, as the reinforcing plate, instead of the perforated plate, a thin and tough non-porous metal plate which can be folded is pressed to superpose the conductive plate mounting area compression plate of the polar plate, and the same effect is obtained. Bring In the second embodiment, the reinforcing plates are arranged on both sides. However, the reinforcing plates are arranged on only one side, the current collecting plate is housed in the concave space without the reinforcing plate, and directly welded to the compression plate portion. May be.

[0028]

As described above, according to the present invention, in the paste type electrode plate comprising the electrode plate main plate portion filled with the active material and the current collector plate mounting area compression plate portion, the reinforcing plate is Not only the area plate part for mounting the current plate, but also a part of the electrode plate main plate part in the periphery thereof is polymerized and pressure-bonded, so that between the electrode plate main plate part and the current plate mounting surface plate part. The rupture strength at the boundary portion of can be significantly increased. When the current collector plate is welded to the reinforcing plate, it facilitates the extraction of electricity from the main plate of the electrode plate to the current collector plate, increases the conductivity, and incorporates the battery into the battery. The discharge characteristics, especially the rapid discharge characteristics, are improved and the battery performance is improved. Further, when the reinforcing plates pressure-bonded by polymerization as described above are provided on both surfaces of the current-collecting plate mounting surface area compression plate portion of the electrode plate, it is possible to further increase the mechanical strength at the boundary portion. it can. In the production of the above-mentioned electrode plate of the present invention, as a reinforcing plate, a three-dimensional perforated plate having a surface area larger than the surface area of a predetermined current collector plate mounting surface area compression plate portion is used, and the surface area is polymerized. The inner surface area plate portion of the reinforcing plate is pressed and pressure-bonded to the surface area compression plate portion for mounting the current collector plate, and the peripheral area plate portion is pressed to compress the main plate portion of the porous plate for polar plate. By binding, the electrode plate having the above various excellent properties can be manufactured. Further, when the marginal area plate portion and the current collector plate of the reinforcing plate are placed on the same plane as or lower than the electrode plate main plate portion, damage to the separator laminated with this and short circuit with the different electrode plate The battery can be assembled smoothly and satisfactorily.

[Brief description of the drawings]

FIG. 1 is a plan view of an electrode plate according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view in which a part of the line II-II of FIG. 1 is cut.

FIG. 3 is a plan view illustrating a first stage of a manufacturing process of an example of carrying out the manufacturing method of the electrode plate of the present invention shown in FIG.

4 is a sectional view taken along the line IV-IV in FIG.

FIG. 5 to FIG. 7 are enlarged cross-sectional views of main parts for explaining respective subsequent manufacturing steps.

FIG. 8 is a cross-sectional view in which a part of an electrode plate according to another embodiment of the present invention is cut away.

9 is a cross-sectional view for explaining the first step of the manufacturing process of another embodiment of the method of manufacturing the electrode plate of the present invention shown in FIG.

FIG. 10 is an enlarged cross-sectional view of a main part of the electrode plate at the final stage.

FIG. 11 is a comparative graph of the discharge characteristics of the electrode plate of the present invention and the conventional electrode plate.

FIG. 12 is a plan view of a conventional electrode plate.

13 is a sectional view taken along the line XIII-XIII in FIG.

[Explanation of symbols]

1 electrode plate 1'porous substrate for electrode plate 1a electrode plate main plate portion 1'a electrode plate porous plate main plate portion 1b current collector plate mounting area compression plate section 1'b current plate mounting surface plate Part 2 Reinforcing plate 2'Reinforcing porous plate 2a Inner surface area plate, inner surface compression plate 2'a Reinforcing inner surface porous plate 2b Edge area plate section, edge area compression plate section 2'b Reinforcing edge area plate Part 2c Boundary 3 Current collector 3a Base of current collector 4 Concave space

Front page continuation (72) Inventor Yoshie Wakiya 72-1 Nakayama, Aoba-ku, Sendai City, Miyagi Prefecture Tohoku Electric Power Co., Inc. Applied Technology Laboratory (72) Inventor Mitsugu Nagano 7-2, Nakayama, Aoba-ku, Sendai City, Miyagi Prefecture No. 1 Tohoku Electric Power Co., Inc. Applied Technology Research Laboratory (72) Inventor Fumio Sato 7-2-1, Nakayama, Aoba-ku, Sendai City, Miyagi Prefecture Tohoku Electric Power Co., Inc. Applied Technology Research Laboratory (72) Ken Koyama Aoba, Sendai City, Miyagi Prefecture 7-2-1, Nakayama, Tokyo Inside Tohoku Electric Power Co., Inc.

Claims (2)

[Claims] 1. An electrode plate comprising an electrode plate main plate portion filled with a paste active material and a collector plate mounting surface area compression plate portion, and at least one surface of the collector plate mounting surface area compression plate portion, Reinforcing plate,
The inner surface area plate portion is polymerized and pressure-bonded to the current collector plate mounting surface area compression plate portion, and the marginal area plate portion is composed of the current collector plate mounting surface area compression plate portion and the electrode plate main plate portion. A part of the main plate of the electrode plate that crosses the boundary is superposed and pressure-bonded, and the base of the current collector is welded to the inner surface plate of the reinforcing plate or the surface compression plate for mounting the current collector. Characteristic paste type electrode plate for alkaline batteries. 2. A surface area larger than the surface area is provided on at least one surface of a predetermined current collector plate mounting surface area plate portion of a porous substrate for polar plate having innumerable three-dimensionally continuous micropores. Polymerizing a reinforcing porous plate having innumerable three-dimensionally continuous micropores, and (b) polymerizing the current collecting plate mounting area plate part of the porous plate for the electrode plate with the same. Pressurizing the inner surface area plate portion of the reinforcing porous plate into a current collector plate mounting surface area compression plate portion and an inner surface area compression plate portion crimped thereto (c)
Pressurizing the marginal area plate portion of the reinforcing porous plate to form the marginal area compression plate portion crimped to a part of the main plate portion, (d)
Filling the main plate portion with a paste active material, (e) pressing the main porous substrate portion filled with the active material to form an electrode plate main plate portion holding the active material, (f) A method for producing a paste type electrode plate for an alkaline battery, which comprises welding the base of the current collector to the inner surface compression plate of the reinforcing plate or the surface compression plate for mounting the current collector.