JP4520105B2 - Battery electrode and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a battery electrode and a method for manufacturing the same, and more particularly, to a battery electrode and a method for manufacturing the same for improving the strength at the lead plate side edge portion in the lead portion.
[0002]
[Prior art]
The prismatic battery is configured by inserting and arranging an electrode plate group in which a plurality of rectangular negative electrode plates and positive electrode plates are alternately stacked via a separator together with an electrolytic solution. For example, the electrode plate group in a nickel metal hydride battery is composed of a positive electrode plate in which Ni foam metal as a support made of a three-dimensional metal porous body is filled with a positive electrode material, and a negative electrode material applied to Ni punching metal as a support. The negative electrode plate is laminated with a separator interposed therebetween.
[0003]
6A and 6B, lead portions 22a and 23a are provided on one side edge portions of the positive electrode plate 22 and the negative electrode plate 23, respectively, and the lead portions 22a and 23a are provided as shown in FIGS. The positive electrode plate 22 and the negative electrode plate 23 are stacked via the separator 24 in a state of protruding to opposite sides, and current collector plates 25 and 26 are provided on the end surfaces of the lead portions 22a and 23a of the positive electrode plate 22 and the negative electrode plate 23, respectively. An electrode plate group 21 is known that is disposed in pressure contact and joined by laser beam welding or electron beam welding with a brazing material or the like interposed as necessary.
[0004]
Further, as shown in FIGS. 7A and 7B, the lead portion 22a of the positive electrode plate 22 pressurizes and compacts one side portion of the three-dimensional metal porous body 27 as a support, and leads to one surface thereof. A structure in which the plates 28 are stacked and joined by ultrasonic welding is known. The lead portion of the negative electrode plate is configured by providing a portion on one side portion of the support plate where no negative electrode material is applied.
[0005]
As a manufacturing method of the lead portion 22a of the positive electrode plate 22, as shown in FIG. 8, a disk-shaped ultrasonic horn that can be rotated with the lead plate 28 superimposed on one surface of the three-dimensional metal porous body 27. Similarly to 31, it is inserted between a rotatable disk-shaped anvil 32, and the lead plate 28 and the three-dimensional metal porous body 27 are pressed between the ultrasonic horn 31 and the anvil 32 to thereby form the three-dimensional metal porous body 27. It is known that the ultrasonic horn 31 is ultrasonically bonded to the entire surface of the porous three-dimensional metal body 27 and the lead plate 28 by applying ultrasonic vibration in the axial direction to the ultrasonic horn 31 (for example, , See Patent Document 1).
[0006]
Further, in the electrode wound in a spiral shape, as shown in FIG. 9, a mesh 34 reinforced by folding is attached to the end portion which becomes the lead portion of the electrode 33, and the end portion is a three-dimensional porous metal body of the electrode 33. It is also known that the electric spot welding is performed at appropriate intervals (see Patent Document 2).
[0007]
[Patent Document 1]
JP 2001-297747 A
[Patent Document 2]
Japanese Patent Laid-Open No. 2000-223128
[Problems to be solved by the invention]
By the way, as in Patent Document 1, in an electrode in which one side edge portion of the three-dimensional metal porous body 27 is consolidated and the lead plate 28 is joined to one surface thereof, the side edge of the lead plate 28 and the three-dimensional metal porous body 27 are combined. There is a problem that stress concentrates on the boundary portion 29 (see FIG. 7B) and bending is likely to occur, and in extreme cases, breakage may occur. By adopting a material having a small (basis weight), the weight of the positive electrode plate 22 can be reduced and the filling amount of the positive electrode material can be increased to increase the capacity per weight of the battery. It becomes a problem.
[0010]
Moreover, in order to solve such a problem, it is conceivable to reinforce the lead portion by providing a folded portion as in Patent Document 2, but in that case, the processing man-hours and the material cost increase, resulting in a high cost. Will cause the problem of becoming.
[0011]
In view of the above-described conventional problems, the present invention provides a battery electrode in which one side edge of a three-dimensional metal porous body is compacted and a lead plate is joined to one surface of the three-dimensional metal porous body at the side edge of the lead plate. An object of the present invention is to provide a battery electrode that does not break or break, and a method for manufacturing the same.
[0012]
[Means for Solving the Problems]
The battery electrode of the present invention is a battery electrode in which a lead plate of a support made of a three-dimensional metal porous body is consolidated to join a lead plate, and the lead plate is joined to one surface of the compacted portion of the support. In addition, a non-consolidated protrusion that extends to a position facing the lead plate is disposed on the other surface of the consolidated portion with a space therebetween, and the lead plate and the non-consolidated protrusion extending to the lead plate side The bending rigidity of the boundary with the three-dimensional metal porous body can be increased, the stress can be reliably prevented from occurring at the boundary, and the three-dimensional metal porous body can be prevented from being bent or broken, and the non-consolidated protrusions are spaced apart. Since it is arranged with a gap, it is possible to secure a sufficient bonding area between the compacted portion of the three-dimensional metallic porous body and the lead plate, and the compacted portion of the three-dimensional metallic porous body and the lead plate are reliably integrated into the machine. It is possible to configure a lead portion with good electrical and electrical characteristics.
[0013]
In addition, the joint between the support and the lead plate can be applied by resistance seam welding or joining with a conductive adhesive, but when the support and the lead plate are ultrasonically joined, the portion facing the non-consolidated protrusion is excluded. Thus, almost the entire surface of the lead plate can be reliably and efficiently joined to the support, and a lead portion having good mechanical and electrical characteristics can be constructed with high productivity.
[0014]
The battery electrode manufacturing method of the present invention is a battery electrode manufacturing method in which a lead plate of a support made of a three-dimensional metal porous body is compacted to join a lead plate. Between a disk-shaped pressurizing jig that can be rotated by overlapping a lead plate on the arrangement part and a disk-shaped anvil that is rotatable and has a recess formed in the side edge of the outer peripheral support surface. The support and the lead plate are joined while pressing the support and the lead plate between the pressurizing jig and the anvil, and the lead arrangement part of the support is inserted between the pressurizing jig and the anvil. By joining the lead plates while forming the non-consolidated protrusions at the recesses of the anvil while being consolidated, a battery electrode that exhibits the above-described effects can be manufactured with high production efficiency.
[0015]
The pressurizing jig is composed of an ultrasonic horn. When ultrasonic vibration is applied to the ultrasonic horn in the axial direction to ultrasonically bond the support and the lead plate, the support and the lead plate are superposed and fed. In addition, almost the entire surface of the lead plate can be reliably and efficiently joined to the support, and a lead portion having good mechanical and electrical characteristics can be constructed with high productivity.
[0016]
In addition, when using an anvil that has concave portions formed in a staggered pattern on both side edges of the outer peripheral support surface, the bonding area at the ultrasonic bonding portion can be made uniform without changing much depending on the rotation position of the ultrasonic horn and the anvil. A stable and highly reliable bonding state can be obtained. In this case, after joining the lead plate, the lead plate is cut at the center thereof and divided into battery electrodes on both sides.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a battery electrode and a manufacturing method thereof according to the present invention will be described with reference to FIGS.
[0018]
In FIG. 1, reference numeral 1 denotes a battery electrode such as a positive electrode plate used in a nickel metal hydride battery, and a lead portion 3 is provided on one side edge of a support 2 made of a foam metal of Ni which is a three-dimensional metal porous body. ing. The lead part 3 is configured by joining a lead plate 5 to one surface of a compacted part 4 formed by compacting a three-dimensional metal porous body by ultrasonic joining. On the other surface of the consolidated portion 4, a non-consolidated protruding portion 6 extending to a position facing the lead plate 5 is disposed at an interval.
[0019]
For example, as shown in FIG. 2, the battery electrode 1 is manufactured in a state of a large plate 7 having a size corresponding to 8 pieces (4 pieces in parallel × 2 rows) and cut along a cutting line 10 indicated by a one-dot chain line. Then, each battery electrode 1 is divided. The large plate 7 is provided with two lead plates 5 </ b> A that are cut at the center portion to form the lead plate 5.
[0020]
When manufacturing the large plate 7 for the battery electrode 1, as shown in FIG. 3, the lead plate 5 A is overlapped on the lead arrangement portion of the support 2, and a rotatable disk-shaped ultrasonic horn 11 and Similarly, the ultrasonic horn 11 is moved by the rotation drive device 14 with an arrow through the disk-shaped anvil 12 which is rotatable and spaced on both side edges of the outer peripheral support surface. The support body 2 and the lead plate between the ultrasonic horn 11 and the anvil 12 are driven between the ultrasonic horn 11 and the anvil 12 by being driven to rotate as shown in FIG. At the same time, the ultrasonic vibration generator 15 applies ultrasonic vibration in the axial direction to the ultrasonic horn 11 as indicated by an arrow c. As a result, as shown in FIG. 4, the consolidation portion 4 is formed in the lead arrangement portion of the support 2, the lead plate 5 </ b> A is ultrasonically bonded to one surface, and the other surface of the consolidation portion 4 is anvil. The non-consolidated protrusions 6 extending to positions facing the lead plate 5 are formed in the recesses 13 formed in a zigzag pattern on both side edges of the outer peripheral support surface 12.
[0021]
As a specific numerical example, the width of the lead plate 5A is 6 mm, the width of the ultrasonic horn 11 and the anvil 12 is 8 mm, and the recess 13 is a semicircular shape having a radius of 2 mm, and is formed at an interval of about 9 to 10 mm.
[0022]
According to the battery electrode 1 having the above-described configuration, the boundary portion between the lead plate 5 and the compacted portion 4 of the support 2 made of the three-dimensional metal porous body at the non-consolidated protruding portion 6 extending to the lead plate 5 side. 8 can increase the bending rigidity, and it is possible to surely prevent the stress from concentrating on the boundary portion 8 and the lead portion 3 from breaking or breaking the compacted portion 4 of the three-dimensional metal porous body 2. In addition, since the non-consolidated protrusions 6 are arranged at intervals, it is possible to secure a sufficient bonding area between the consolidated part 4 of the three-dimensional metal porous body 2 and the lead plate 5, and to prevent the three-dimensional metal porous The consolidated portion 4 and the lead plate 5 of the body 2 can be reliably integrated to form a lead portion with good mechanical and electrical characteristics.
[0023]
Further, since the consolidated portion 4 of the support 2 and the lead plate 5 are ultrasonically bonded, almost the entire surface of the lead plate 5 is reliably and efficiently provided with the consolidated portion 4 except for the portion facing the non-consolidated protruding portion 6. The lead portion 3 having good mechanical and electrical characteristics can be configured with high productivity.
[0024]
In addition, when the lead plate joining apparatus shown in FIG. 3 is used, the support 2 and the lead plate 5 are superposed and fed together with the rotation of the ultrasonic horn 11 and the anvil 12 to form the compacted portion 4. The consolidated portion 4 and the lead plate 5 can be ultrasonically joined by ultrasonic vibration in the axial direction of the sonic horn 11, and the lead portion 3 having good mechanical and electrical characteristics can be constructed with good productivity, and in particular, the concave portion 13. Since the conventional lead plate joining apparatus can be applied as it is simply by using the anvil 12 formed with the structure, the battery electrode 1 having the above-described effects can be manufactured at a low cost with almost no equipment cost. Furthermore, since the anvil 12 in which the concave portions 13 are formed in the staggered shape on both side edges of the outer peripheral support surface is used, the bonding area in the ultrasonic bonding portion varies greatly depending on the rotational positions of the ultrasonic horn 11 and the anvil 12. Therefore, a stable and reliable joining state can be obtained.
[0025]
Other When a specific example, as shown in FIG. 5 (a), the battery electrode 1 of the embodiment using basis weight (basis weight) of a three-dimensional metallic porous body 2 of 400 g / m ² as a support 2 When the lead plate 3 and the current collector plate 9 are welded and joined with the current collector plate 9 pressed against the edge of the lead portion 3, the lead portion 3 is broken or cut. Thus, the lead portion 3 could be appropriately welded to the current collector plate 9. In contrast, in the positive electrode plate 22 of the prior art, the mass per unit area (basis weight) of the had using three-dimensional metallic porous body 27 of 600 g / m ^2, similarly basis weight (basis weight) of 400 g / m ² When it was changed to a thing, as shown in FIG.
[0026]
【The invention's effect】
According to the battery electrode of the present invention, the bending rigidity at the boundary between the lead plate and the three-dimensional metal porous body can be increased by extending the non-consolidated protrusion on the lead plate side, and stress concentrates on the boundary. Therefore, it is possible to reliably prevent the three-dimensional metal porous body from being broken or broken, and the non-consolidated protrusions are arranged at intervals, so that the three-dimensional metal porous body is bonded to the lead plate. A sufficient area can be secured, and the compacted portion of the three-dimensional metal porous body and the lead plate can be reliably integrated to constitute a lead portion having good mechanical and electrical characteristics.
[Brief description of the drawings]
1A and 1B show a battery electrode according to an embodiment of the present invention, in which FIG. 1A is a front view, FIG. 1B is a partially enlarged rear view, and FIG. 1C is a cross-sectional view taken along line AA in FIG. .
FIG. 2 is a front view of the large plate before division of the battery electrode according to the embodiment;
FIG. 3 is a configuration diagram of a lead plate bonding apparatus according to the embodiment.
FIG. 4 is an enlarged sectional view showing a lead plate joined state in the same embodiment;
FIG. 5 is a detailed cross-sectional view showing a joined state between the lead portion of the battery electrode and the current collector plate of the embodiment and the conventional example.
6A and 6B show a configuration of an electrode plate group, in which FIG. 6A is a perspective view, and FIG. 6B is an enlarged cross-sectional view taken along line BB in FIG.
7A and 7B show a configuration of a conventional battery electrode, in which FIG. 7A is a front view of a main part, and FIG. 7B is a cross-sectional view taken along the line CC of FIG.
FIG. 8 is a configuration diagram of a lead plate joining apparatus in a conventional example.
9A and 9B show the configuration of another conventional battery electrode, where FIG. 9A is a front view of the main part, and FIG. 9B is a cross-sectional view taken along line DD in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Battery electrode 2 Support body 3 which consists of a three-dimensional metal porous body Lead part 4 Consolidation part 5, 5A Lead plate 6 Non-consolidation protrusion part 11 Ultrasonic horn 12 Anvil 13 Concave part

Claims (6)

A battery electrode in which a lead plate of a support made of a three-dimensional metal porous body is consolidated to join a lead plate, the lead plate being joined to one surface of the consolidated portion of the support, and the other surface of the consolidated portion In addition, a non-consolidated protrusion including a portion facing the boundary between the lead plate and the support and extending to a position facing the lead plate is arranged at a distance along the side edge of the support. A battery electrode characterized by being provided.   The battery electrode according to claim 1, wherein the support and the lead plate are ultrasonically bonded. A method of manufacturing a battery electrode in which a lead arrangement part of a support made of a three-dimensional metal porous body is compacted and joined to a lead plate, wherein the lead plate is superimposed on the lead arrangement part of the support and is rotatable inserted between a plate-like pressing jig, and rotatable in and the outer circumferential supporting face disc-shaped anvil to the side edges along the circumferential direction to form a recess apart, pressing jig A method of manufacturing a battery electrode, wherein the support and the lead plate are joined while pressing the support and the lead plate between the anvil and the anvil.   4. The battery electrode according to claim 3, wherein the pressurizing jig comprises an ultrasonic horn, and ultrasonic support is applied to the ultrasonic horn in the axial direction to ultrasonically bond the support and the lead plate. Manufacturing method. The method for manufacturing a battery electrode according to claim 3 or 4, wherein an anvil in which concave portions are formed in a staggered manner along the circumferential direction at both side edges of the outer peripheral support surface.   A battery comprising the battery electrode according to claim 1.

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