JP2623311B2 - Manufacturing method of electrode plate for bipolar battery - Google Patents

Description

The present invention relates to a method for manufacturing an electrode plate for a bipolar battery.

[Conventional technology]

A conventional method for manufacturing a bipolar battery electrode plate, for example, in the method for manufacturing a bipolar electrode plate, after integrally attaching an electrically insulating frame to the periphery of the conductive plate via an adhesive,
On both concave surfaces formed by the surrounding frame and both surfaces of the conductive plate, one of the concave surfaces is filled and coated with a cathode active material to form a cathode active material coating layer, and the other concave surface is coated with an anode active material. Filling to form an anode active material coating layer produces a bipolar electrode plate.

[Problems to be solved by the invention]

In the bipolar electrode according to the above-described manufacturing method, the conductive plate and the surrounding frame are sealed and bonded with an adhesive over the four circumferences thereof. Since the material properties such as the expansion rate and the contraction rate are different, it is difficult to completely seal and bond both members.

In addition, even when the adhesive is completely adhered at first, the adhesive may be deteriorated due to heat generated by high-rate discharge or the like during the operation of the battery, resulting in poor adhesion. Thus, if the adhesion between the conductive plate and the surrounding frame is poor, there is a danger that the electrolyte solution leaks from the poor adhesion portion. Further, when the conductive plate and the surrounding frame are well bonded to each other by an adhesive, the adhesive is reduced by an electrolytic solution that comes into contact during use thereof,
There is an inconvenience in that a poor bonding portion is generated, which causes the electrolyte to flow and leak, thereby shortening the battery life.

[Means for solving the problem]

The present invention solves the above-mentioned problems, and solves the above-described disadvantages during use as a bipolar battery. Even if there is a bonding failure between the conductive plate and the surrounding frame, the electrolytic solution from the defective portion. The present invention provides a method for manufacturing a stable and robust bipolar battery electrode plate without penetrating, extending the service life, and fixing an electrically insulative enclosure around the periphery of the conductive plate. After applying a water repellent over the conductive plate surface and the inner peripheral surface of the enclosing frame so as to cover the intersection boundary with the inner peripheral surface of the enclosing frame, the enclosing frame and the conductive plate surface are formed. The active material is coated on the concave surface by filling and coating the active material.

(Operation)

According to the present invention, the water-repellent coating is provided in the state of use, that is, the water-repellent coating is provided so as to cover the crossing boundary portion and straddle the conductive plate surface and the inner peripheral surface of the surrounding frame. In the processing section, the electrolytic solution is prevented from entering from the intersection between the conductive plate and the enclosure, and even if there is a poor adhesion between the conductive plate and the enclosure, To prevent the electrolyte solution from invading and leaking, thereby increasing the battery life.

〔Example〕

 Next, embodiments of the present invention will be described with reference to the accompanying drawings.

1 to 3 show one embodiment of the present invention. 1
Denotes a flat plate or a film and a conductive plate, and the conductive plate 1
Is made of a rectangular metal plate having excellent conductivity, impermeability and corrosion resistance. 2 is an adhesive 3 on the four peripheral edges of the conductive plate 1.
2 shows an electrically insulating enclosure fixedly mounted via a. The fixing means 3 for the two members 1 and 2 is shown in the case of applying an adhesive in the illustrated example, but may be bonding, heat fusion, injection molding, or the like. This is a molded body surrounding frame having an annular concave groove 2a having a U-shaped cross section on the inner periphery formed by molding.

Thus, rectangular concave surfaces 4, 4 surrounded by the U-shaped surrounding frame 2 are formed on both sides of the conductive plate 1 of the framed electrode plate substrate thus configured. According to the conventional production, a cathode active material and an anode active material having polarities different from each other are filled and applied to the biconcave surfaces 4, 4 of such a framed conductive plate, and the respective active material layers are formed. According to the present invention,
Before this active material filling operation, the boundary 5 between the both surfaces 1a, 1a of the conductive plate 1 and the inner peripheral surfaces 2b, 2b of the enclosure 2, that is, the four-peripheral boundary 5
Is applied with a water repellent 6. The coating treatment of the water repellent,
The conductive plate surface 1 and the inner peripheral surface 2b of the surrounding frame 2 perpendicular to the conductive plate surface 1 are formed by spraying or spraying a plastic, an acid-resistant paint, a fluororesin such as Teflon, or another water-repellent substance dissolved in an organic solvent. By coating over the conductive plate surface 1 and the inner peripheral surface 2b of the enclosure 2 so as to cover the intersecting four-circumferential boundary part 5, a water-repellent coating film 6 is formed on the four peripheral surfaces. is there. The width and thickness of the coating film 6 are arbitrarily selected according to the purpose. The water repellent 6 is preferably a heat-resistant one.

As shown in FIG. 2, the water-repellent agent coating process is performed so that the conductive plate surface 1 and the inner peripheral surface of the enclosure 2 intersect at right angles with each other so as to cover the boundary portion 5. A coating line having a substantially triangular cross section or a thin strip-shaped coating line having a rectangular cross section applied to the four peripheral surfaces of the conductive plate surface 1 and the inner peripheral surface of the enclosure 2 as shown in FIG. It is optional, for example, to apply a state in which a part of the boundary line 5 is covered. As the conductive plate 1, in the case of a lead battery, a lead plate, a conductive plastic plate obtained by mixing conductive fibers, metal powder, and the like into a plastic material, and the like can be considered. In the case of an alkaline battery such as a nickel-cadmium battery, For example, a nickel plate, a conductive plastic plate or the like can be considered.

According to the present invention, the concave surface formed by both surfaces of the conductive plate 1 and the surrounding frame 2 after the water-repellent agent coating treatment as described above.
4, 4 are coated with active materials having different polarities, respectively, and an anode active material coating layer 7 is provided on one side thereof and a cathode active material coating layer 8 is provided on the other side thereof. Get 9.

FIG. 5 shows an example in which the present invention is applied to a monopolar electrode plate acting as a current collector plate constituting a bipolar battery. An enclosing frame 2 having an L-shaped cross section is provided on the periphery of a conductive plate 1 with an adhesive 3 interposed therebetween. In the same manner as in the embodiment of FIG. 4, the water-repellent coating is applied to the four-circumferential boundary 5 between the enclosing frame 2 and the conductive plate 1 formed on one surface of the framed electrode plate substrate which is integrally bonded. The film 6 is formed by coating on four sides, and the concave surface 4 is filled with a cathode active material or an anode active material, and is provided with a coating layer 7 or 8 thereof.

FIG. 6 shows a structure in which the bipolar electrode 9 and the monopolar electrode (current collector) 10 configured as described above are laminated with a separator 11 having a frame 11a interposed therebetween in a state of being impregnated with an electrolytic solution. Then, the adjacent frames were airtightly bonded to each other via an adhesive to form a series bipolar battery. 12,13
Denotes positive and negative current collecting terminals provided on the monopolar plates (current collecting plates) 10 at both ends. For comparison, a conventional bipolar bipolar plate and a monopolar polar plate (current collecting plate) of the present invention, which were not subjected to the water repellent treatment, were simultaneously assembled and laminated to form a conventional serial bipolar battery. Both batteries have a discharge capacity of 10Ah (5H
R), the open circuit voltage was 6V.

When a life test was performed on each of these five batteries,
In the conventional battery, the open circuit voltage dropped in 15 to 30 cycles, and the battery could not function as a 6V battery. In contrast, the batteries of the present invention maintained an open-circuit voltage of 6 V even after 100 cycles of all five batteries. In some electrode plates of the conventional battery, intrusion and leakage of the electrolyte solution were observed in the adhesive joint between the conductive plate and the surrounding frame.

[Effects of the Invention] As described above, according to the present invention, in producing a bipolar battery electrode plate, the conductive plate and the inner peripheral surface of the enclosure fixed to the outer peripheral edge thereof are covered so as to cover the intersection. After applying a water repellent over the conductive plate surface and the inner peripheral surface of the enclosure, the active material is applied to the concave surface formed by the conductive plate surface and the enclosure, and the coating layer is provided. Since the electrode plate is formed, the water-repellent coating prevents the electrolyte from entering the bonding portion between the conductive plate and the enclosure through the boundary, and lowers the adhesive strength due to contact with the electrolyte. This prevents the electrolyte solution from leaking and, when assembled into a battery, has the effect of extending the service life of the battery.

[Brief description of the drawings]

1 to 3 show an embodiment of the present invention. FIG. 1 is a front view of a bipolar electrode plate with a frame of the present invention, and FIG.
The figure is a sectional view taken along the line II-II, FIG. 3 is a sectional view of a bipolar electrode plate, FIG. 4 is a sectional view of a modified example, and FIG. 5 is a sectional view of a monopolar electrode plate. FIG. 6 is a sectional view of a group of electrode plates of a bipolar battery assembled with the electrode plate of the present invention. DESCRIPTION OF SYMBOLS 1 ... Conductive plate, 1a ... Conductive plate surface, 2 ... Surrounding frame 2b ... Surrounding frame inner peripheral surface, 3 ... Adhesive, 4 ... Concave surface 5 ... Boundary part, 6 ... Water repellent, Water repellent coating, 7 ... Anode active material coating layer 8 ... Cathode active material coating layer, 9 ... Bipolar electrode plate 10 ... Monopolar electrode plate, current collector plate 11 ... Separator, 11a ... Separator frame

Claims (1)

(57) [Claims] 1. An electric insulating frame is fixed to a peripheral edge of a conductive plate, and then the conductive plate surface and the enclosure are covered so as to cover an intersection between the conductive plate surface and an inner peripheral surface of the enclosure. After applying a water repellent over the inner peripheral surface of the conductive material, the concave surface formed by the surrounding frame and the conductive plate surface is filled with an active material, and the active material coating layer is provided. A method for producing a bipolar battery electrode plate.