WO2001004979A1

WO2001004979A1 - Method of manufacturing battery core body

Info

Publication number: WO2001004979A1
Application number: PCT/JP2000/004593
Authority: WO
Inventors: Hitoshi Ohmura; Tatsuo Tomomori; Hiroshi Nakashima; Hiroyuki Okano
Original assignee: Toyo Kohan Co., Ltd.
Priority date: 1999-07-09
Filing date: 2000-07-10
Publication date: 2001-01-18
Also published as: AU5709400A; TW477726B

Abstract

A method of maufacturing a battery core body capable of increasing the productivity of the battery core body by raising a punching speed, comprising the steps of pressing a punching roll (54) having a plurality of working projections (53) on the outer peripheral surfaces in circumferential and longitudinal directions, while rotating, agains a steel sheet (50) having surfaces on which graphite dispersed nickel plated layers (51, 52) are formed so as to form a punched sheet metal (57) having a plurality of holes (56) by punching upper, and rolling the punched sheet metal (57) together with the punched up portions (58, 59) by rolling rolls (60, 61).

Description

Description Manufacturing method of battery core

TECHNICAL FIELD The present invention relates to a method for manufacturing a perforated metal plate used for forming a core of a secondary battery electrode. BACKGROUND ART In recent years, there has been an increasing demand for perforated metal plates having a large number of holes, which are used for electrode cores of secondary battery electrodes, particularly nickel-metal hydride batteries and nickel-cadmium batteries. The perforated metal plate for the secondary electrode core is wound by attaching an active material to the surface thereof, and is filled in a battery container. At this time, the holes are formed in the metal plate for the purpose of providing an anchor effect for urging the active material to adhere to the metal plate and filling the holes with the active material. In order to increase the battery capacity, it is necessary to fill the battery container with as much active material as possible. Therefore, a perforated metal plate for the electrode core is required to be as thin as possible.

Conventionally, as a method of manufacturing a perforated metal plate, a method of perforating using a punching press is generally used.

However, the above-described method for manufacturing a battery core has the following problems to be solved.

That is, in the punching method using a punching press, the metal plate to be punched is supplied intermittently, and the metal plate must be stopped during the press working, and a huge force is applied to the press device. It was extremely difficult to improve the productivity of perforated metal sheets by increasing the perforation speed in conjunction with the operation. The present invention has been made in view of such a situation, and has as its object to provide a method for manufacturing a battery core, which can increase the drilling speed and improve the productivity of the battery core. . Disclosure of the invention

In order to achieve the above object, a method for manufacturing a battery core according to the first invention comprises: a metal plate having a nickel plating layer or a graphite-dispersed nickel plating layer formed on a surface thereof; A plurality of recesses are formed by pressing a concave roll provided with a large number of processing projections against a metal plate while rotating the metal plate, and the metal plate is rolled with a rolling knurl to break the concave portions to form holes. It is characterized by forming a perforated metal plate and manufacturing a battery core.

The method for manufacturing a battery core according to the second invention is characterized in that a metal plate having a nickel plating layer or a graphite-dispersed nickel plating layer formed on a surface thereof is provided with a large number of processing projections on an outer peripheral surface in a circumferential direction and a longitudinal direction. The punched roll is pressed while rotating to form a perforated metal plate having a large number of holes having a return portion, and the return portion is folded using a folding means. Rolling to produce a battery core.

The method for manufacturing a battery core according to the third invention is characterized in that a metal plate having a nickel-plated layer or a graphite-dispersed nickel-plated layer formed on its surface is provided with a large number of processed protrusions in the circumferential direction and the longitudinal direction on the outer peripheral surface. The perforated roll is pressed against the metal plate while being rotated, cut and raised to form a perforated metal plate having a large number of holes, and the perforated metal plate is rolled together with the cut and raised portion with a rolling roll to produce a battery core. It is characterized by the following.

The method for manufacturing a battery core according to the fourth invention is characterized in that a concave roll having a large number of processing projections provided on an outer peripheral surface in a circumferential direction and a longitudinal direction is pressed while rotating a metal plate to form a large number of concave portions. The perforated metal plate is formed by rolling the metal plate with rolling rolls to break the recesses to form holes, and to form a nickel plating layer or a graphite-dispersed nickel plating layer on the surface of the perforated metal plate. Is formed.

A method for manufacturing a battery core according to a fifth aspect of the present invention is directed to a method for manufacturing a battery core, comprising the steps of: rotating a perforation roll having a large number of processing projections on an outer peripheral surface in a circumferential direction and a longitudinal direction; A perforated metal plate having holes is formed, a return portion is turned back using a turning means, and the perforated metal plate is rolled together with the turned portion by a rolling roll, and then a nickel plating layer or a graphite dispersed nickel plating layer is formed on the surface. It is characterized by doing.

The method for manufacturing a battery core according to the sixth invention is characterized in that a punching roll provided with a large number of processing projections on the outer peripheral surface in the circumferential direction and in the longitudinal direction is pressed against a metal plate while being rotated and cut and raised to a large number. A perforated metal plate having holes is formed, and the perforated metal plate is rolled together with a cut-and-raised portion with a rolling roll, and then a nickel plating layer or a graphite-dispersed nickel plating layer is formed on the surface. In the above-described first to sixth methods for manufacturing a battery core, the nickel plating layer is not limited to a nickel plating layer made of only nickel, but may be a nickel alloy, for example, a nickel-cobalt alloy or a nickel-cobalt alloy. It shall include a nickel alloy plating layer made of a ferrous alloy, a nickel-manganese alloy, a nickel-phosphorus alloy, a nickel-bismuth alloy, or the like.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic process explanatory view of a method for manufacturing a battery core according to a first embodiment of the present invention. FIG. 2 is a schematic process explanatory view of a method for manufacturing a battery core according to a second embodiment of the present invention. FIG. 3 is a schematic process explanatory view of a method for manufacturing a battery core according to a second embodiment of the present invention. FIG. 4 is a schematic process explanatory view of a method for manufacturing a battery core according to the second embodiment of the present invention. FIG. 5 is a schematic process explanatory view of a method for manufacturing a battery core according to the third embodiment of the present invention. FIG. 6 is a schematic process explanatory view of a method for manufacturing a battery core according to a fourth embodiment of the present invention. FIG. 7 shows schematic steps of a method for manufacturing a battery core according to a fifth embodiment of the present invention. FIG. FIG. 8 is a schematic process explanatory view of a method for manufacturing a battery core according to a sixth embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be specifically described with reference to some embodiments shown in the accompanying drawings.

(First Embodiment)

With reference to FIGS. 1 and 2, a method for manufacturing a battery core according to the first embodiment of the present invention will be described.

(1) First, as shown in FIG. 1, after preparing a steel sheet 10 as an example of a metal sheet, the mild steel sheet 10 is coated with a graphite-dispersed nickel plating layer 11 1 or 12 (a nickel plating layer or graphite). (A dispersed nickel alloy plating layer may be used).

Specifically, as the steel sheet 10 to be used, a cold-rolled steel sheet of ordinary steel, particularly one based on low carbon aluminum-killed copper continuous steel is used. In addition, ultra-low carbon steel having a carbon content of 0.003% by weight or less, non-aging promotion in which a metal such as niobium or titanium is added thereto, or a stainless copper plate containing a chromium content of 3 to 18% by weight Etc. can also be used.

For the surface-treated copper plate, first, it is desirable to apply nickel plating on the copper plate. This nickel plating is hereinafter referred to as “base nickel” plating. The purpose of the base nickel plating is to ensure sufficient corrosion resistance even inside the battery.

As the base nickel plating bath, a bath used for ordinary nickel plating, such as a watt bath, a sulfamic acid bath, a borofluoride bath, and a chloride bath, can also be used in the present invention. As the electrolysis method conditions, it is preferable that the current density is 3 to 80 AZ dni ² and that the bath is air-stirred by blowing air into the bath in order to obtain a uniform plating layer. The pH of the bath is preferably in the acidic range of 3.5 to 5.5, and the bath temperature is preferably 40 to 60 ° C. As the base nickel plating treatment, either a non-glossy plating using no organic additive or a semi-glossy plating using an organic additive can be used. The nickel adhesion amount of the nickel plating layer is preferably about 0.5 to 5 // m.

If the amount of adhesion is less than 0.5 μπι, the coating on the steel sheet is insufficient, so that the corrosion resistance for the purpose of base nickel plating cannot be sufficiently secured. On the other hand, if the amount exceeds the limit, the effect is saturated and it is economically disadvantageous. The nickel base plating is preferably formed on both sides of the steel sheet from the viewpoint of ensuring corrosion resistance, and the thickness of the plating layer is preferably 0.5 to 5 μπι.

The underlying nickel plating layer may be left attached, but heat treatment may be performed after plating to make all or part of the nickel plating layer a diffusion layer.

The heat treatment is preferably performed under a non-oxidizing or reducing protective gas in order to prevent formation of an oxide film on the surface of the diffusion layer. As the non-oxidizing gas, nitrogen, argon, helium, etc., which are so-called inert gases, are suitably used. On the other hand, as the reducing gas, hydrogen, ammonia cracking gas (75% hydrogen, 25% nitrogen), etc. Is preferably used. As the heat treatment method, there are a box annealing method and a continuous annealing method, and either method may be used. In the case of box-type annealing, the heat treatment temperature is preferably 450 ° C. or higher, and the processing time is short in the continuous annealing method, and is relatively long in the box-type annealing method. Generally, for continuous annealing, it is preferably about 30 seconds to 2 minutes, and for box annealing, about 6 hours to 15 hours.

Next, a graphite-dispersed nickel plating layer or a graphite-dispersed nickel alloy plating layer is formed.

This graphite-dispersed nickel plating bath may be based on a nickel plating bath (where a graphite-dispersed nickel plating layer is formed) or may be formed of a metal other than nickel, such as cobalt, manganese, iron, phosphorus, bismuth, and nickel. This is performed using an alloy bath as a base and a bath in which graphite is dispersed in the bath (a graphite-dispersed nickel alloy coating layer is formed). Use a plating bath in which graphite, an excellent conductive agent, is dispersed. As a result, the graphite is dispersed and eutectoidized in the plating layer together with the formation of the plating layer, and the retention of the active material in the battery is improved by the anchor effect of the convex prayer.

The graphite used in the present invention may be either natural graphite or artificial graphite, but it is preferable to use finely ground graphite having a 50% cumulative diameter of 10 / m or less. Further, it is more preferable to use ultrafine graphite having a 50% cumulative diameter of 5 // m or less. This is because if graphite having a very large particle size is used as compared with the thickness of the plating layer, the attached graphite tends to fall off. Graphitized carbon black can also be used.

Because graphite has a hydrophobic surface, it is not easy to disperse it even if it is stirred in a plating bath. Therefore, it is desirable to forcibly disperse using a surfactant (graphite dispersant). As the graphite dispersant used, any of cationic, anionic, nonionic and amphoteric types can be used, but the adhesion between the coated steel sheet and the coated layer is good and the plating is good. Considering that the layer is less embrittled, it is preferable to use an anionic surfactant as a graphite dispersing agent. Among the anionic surfactants, benzenesulfonic acid or sulfate ester is preferable. Aqueous activators, for example, sodium alkyl sulfate, sodium dodecylbenzene sulfonate, sodium α-olefin sulfonate, sodium alkyl naphthalene sulfonate, dialkyl sodium 2-sulfosuccinate, and the like are more preferred as the graphite dispersant of the present embodiment. New

The method of dispersing the fine graphite in the plating solution is to knead the graphite powder and a graphite dispersant diluted with a certain amount of water, and finally use a homogenizer or an emulsifying mixer such as an ultrasonic washing machine to disperse the dispersed state. To In this case, a method of moistening the graphite powder with a small amount of alcohol or the like is also effective for dispersion. After the graphite is sufficiently dispersed in this way, the graphite is added with stirring in the plating solution. It is desirable to adjust the blending amount of the dispersant so that the final amount of the dispersing agent is 1 to 100 g ZL. If the amount is less than 1 g ZL, the graphite content in the coating is too low and there is no anchor effect. On the other hand, if it exceeds 100 g / L, the fluidity of the plating solution will deteriorate, This is because various troubles are likely to occur by adhering to the periphery of the attached layer. In addition, a dispersant is added in advance to the plating solution in an amount of about 2 to 1 OmlZL in order to suppress the aggregation of graphite particles.

The plating solution in the plating bath, which has been dispersed in graphite, is used as a pump in the circulation tank to circulate the plating solution to the lower part of the electrolytic cell and to blow air from pores provided in the lower part of the electrolytic cell. It is preferable that the graphite powder is always dispersed in the plating bath by both methods of stirring. If the dispersion state can be maintained well, graphite having a content of about 0.1 to 5% can be dispersed in the plating layer. Among them, it is preferable to disperse at about 0.5 to 2%. In forming the graphite-dispersed coating layer, it is preferable to lower the current density in order to increase the graphite content.

(2) The copper plate 10 on which the graphite-dispersed nickel plating layers 11 and 12 are formed on the surface in this manner, as shown in FIG. The upper and lower pairs of concave rolls 15 and 16 provided with 14 are pressed while rotating to form a large number of concaves 17 and 18.

(3) As shown in FIG. 1, the steel sheet 10 is rolled by rolling rolls 19 and 20 forming an upper and lower pair, the recesses 17 and 18 are broken, a hole 21 is provided, and a perforated metal plate 22 is formed. Used as a battery core. Then, a nickel hydroxide slurry is applied on the battery core to form a positive electrode plate, or a slurry containing a hydrogen storage alloy is applied on the battery core to form a negative electrode plate.

As described above, in the present embodiment, the use of the concave rolls 15 and 16 and the rolls 19 and 20 can increase the perforation speed and improve the productivity of the battery core. Also, when a graphite-dispersed nickel plating layer or a graphite-dispersed nickel alloy plating layer is used as the plating layer, a concave-convex surface is formed due to the nickel-graphite dispersed layer, and the active material retention property is increased. Can be increased.

(Second embodiment) With reference to FIGS. 2 to 4, a method for manufacturing the battery core according to the second embodiment of the present invention will be described.

(1) First, as shown in FIG. 2, after preparing a steel plate 30 as an example of a metal plate by the method described in the first embodiment, a graphite-dispersed nickel plating layer 31 is formed on the copper plate 30. , 32 (a nickel plating layer or black $ ^/ hole, a dispersed nickel alloy plating layer may be formed).

(2) As shown in Fig. 2, a steel plate 30 is provided with a number of projections 33 on its outer peripheral surface in the circumferential direction and the longitudinal direction. A perforated metal plate 37 having a number of holes 36 having holes is formed.

(3) As shown in FIG. 3, a return portion 35 is folded using a tapered rigid body 38 which is an example of a return means, and a perforated metal plate 40 having a return portion 39 is formed.

(4) As shown in FIG. 4, the perforated metal plate 40 is rolled by rolling rolls 41 and 42 forming an upper and lower pair to produce a battery core. Then, a nickel hydroxide slurry is applied on the battery core to form a positive electrode plate, or a slurry containing a hydrogen storage alloy is applied on the battery core to form a negative electrode plate.

As described above, also in the present embodiment, by using the punching roll 34, the tapered rigid body 38, and the rolling rolls 41 and 42, the punching speed is increased and the productivity of the battery core body is increased. Can be improved. In addition, when a graphite-dispersed nickel plating layer or a graphite-dispersed nickel alloy plating layer is used as the plating layer, an uneven surface is formed due to the nickel-graphite dispersed layer, and the active material retention property is increased. Can be increased.

(Third embodiment)

With reference to FIG. 5, a method for manufacturing a battery core according to the second embodiment of the present invention will be described.

(1) First, as shown in FIG. 5, a metal plate is formed by the method described in the first embodiment. After preparing a steel sheet 50 as an example, the graphite-dispersed nickel plating layers 51 and 52 (a nickel plating layer or a graphite-dispersed nickel alloy plating layer may be formed) are formed on the steel sheet 50.

(2) As shown in Fig. 5, a steel plate 50 is provided with a large number of 5 processing projections 53 on the outer peripheral surface in the circumferential and longitudinal directions. A perforated metal plate 57 having a large number of holes 56 is formed by pressing and cutting and raising.

(3) The perforated metal plate 57 together with the cut-and-raised portions 58 and 59 is rolled up and down by rolling rollers 60 and 61 forming a lower pair to produce a battery core. Then, a nickel hydroxide slurry is applied to the battery core to form a positive electrode plate, or a slurry containing a hydrogen storage alloy is applied to the battery core to form a negative electrode plate.

As described above, also in the present embodiment, by using the punching roll 54, the cut-and-raise roll 55, and the rolling rolls 60 and 61, the drilling speed is increased, and the productivity of the battery core is increased. Can be improved. In addition, when a graphite-dispersed nickel-plated layer or a graphite-dispersed nickel-plated alloy layer is used as the plating layer, an uneven surface is formed due to the nickel-dispersed layer of graphite and nickel. The retention of the substance can be improved.

(Fourth embodiment)

With reference to FIGS. 6 (a) and 6 (b), a method for manufacturing a battery core according to a fourth embodiment of the present invention will be described.

As shown in FIG. 20, this embodiment is different from the first embodiment in that concave rolls 15 and 1 are provided with a large number of processing projections 13 and 14 in the circumferential and longitudinal directions on the outer peripheral surface. 6 is pressed while rotating against a metal plate to form a large number of recesses, and the metal plate is rolled by rolling rolls 19 and 20 to break the recesses to form holes 70 to form a perforated metal plate 71. And forming a graphite-dispersed nickel plating layer 72, 73 on the surface of the perforated metal plate 71.

2 5 signs.

Also in this embodiment, the recesses 15 and 16 and the rolling rolls 19 and 20 are used. By doing so, the drilling speed can be increased and the productivity of the battery core can be improved. Also, when a graphite-dispersed nickel plating layer or a graphite-dispersed nickel alloy plating layer is used as the plating layer, there is a nickel-graphite dispersed layer, so that an uneven surface is formed to enhance the retention of the active material. be able to. Further, since the graphite-dispersed nickel plating layer 74 is also formed in the hole 70, the corrosion resistance of the battery core can be further improved.

(Fifth embodiment)

A method for manufacturing a battery core according to a fifth embodiment of the present invention will be described with reference to FIGS. 7 (a) and 7 (b).

As shown in the figure, in the present embodiment, while rotating a punch roll 34 provided with a large number of processing projections 33 in the circumferential direction and the longitudinal direction on the outer peripheral surface used in the second embodiment, The plate is pressed to form a perforated metal plate 81 having a large number of holes 80 having a return portion, and the return portion is folded back using a tapered rigid body 38 which is an example of a return means. At the same time, the perforated metal plate 81 is rolled by rolling rolls 41 and 42, and then the graphite-dispersed nickel plating layers 82 and 83 are formed on the surface.

Also in the present embodiment, the use of the piercing roll 34, the tapered rigid body 38, and the rolling rolls 41, 42 increases the piercing speed to improve the productivity of the battery core. Can be done. In addition, when the graphite-dispersed nickel plating layers 82 and 83 are used as the plating layer, there is a dispersion layer of nickel and graphite, so that an uneven surface is formed and the retention of the active material can be improved. it can. Further, since the graphite-dispersed nickel plating layer 84 is also formed in the hole 80, the corrosion resistance of the battery core can be further improved.

(Sixth embodiment)

With reference to FIGS. 8 (a) and 8 (b), a method for manufacturing a battery core according to the sixth embodiment of the present invention will be described. As shown in the figure, in the present embodiment, a punching roll 54 provided with a large number of processing projections 53 in the circumferential and longitudinal directions on the outer peripheral surface used in the third embodiment is rotated on a metal plate. A perforated metal plate 91 having a large number of holes 90 is formed by pressing and cutting and raising, and the perforated metal plate 91 is rolled by a rolling roll together with the cut and raised portion, and then a graphite-dispersed nickel plating layer 92 on the surface is formed. 93 is formed. Also in the present embodiment, the use of the perforation roll 54, the cut-and-raise roll 55, and the rolling rolls 60 and 61 increases the perforation speed and improves the productivity of the battery core. Can be. In addition, when the graphite-dispersed nickel plating layers 92 and 93 are used as the plating layer, the nickel-graphite dispersed layer is provided, so that an uneven surface is formed and the retention of the active material can be improved. . Furthermore, since the graphite-dispersed nickel plating layer 94 is also formed in the hole 90, the corrosion resistance of the battery core can be further improved. Industrial applicability

As described above, in the present invention, the productivity of the battery core can be improved by increasing the perforation speed. Also, when a graphite-dispersed nickel plating layer or a graphite-dispersed nickel alloy plating layer is used as the plating layer, there is a nickel-graphite dispersed layer, so that an uneven surface is formed and the active material retainability is improved. Can be increased. Furthermore, in the case of forming the perforated layer after forming the perforated metal plate, the plating layer is also formed in the holes, so that the corrosion resistance of the battery core can be further improved.

Claims

The scope of the claims

1. On a metal plate with a nickel plating layer or graphite-dispersed nickel plating layer formed on the surface, a concave roll provided with a large number of processing projections in the circumferential and longitudinal directions on the outer peripheral surface is pressed while rotating on the metal plate. Forming a plurality of recesses, rolling the metal plate with a rolling roll and breaking the recesses to form holes and form a perforated metal plate, and manufacturing a battery core; Manufacturing method.

2. A metal plate having a nickel plating layer or graphite dispersed nickel plating layer on its surface is pressed and rotated while rotating a punch roll provided with a large number of processing projections on the outer peripheral surface in the circumferential and longitudinal directions. Forming a perforated metal plate having a large number of holes having the following, folding the returned portion using a folding means, and rolling the perforated metal plate together with the folded portion with a rolling roll to produce a battery core body. A method for producing a battery core, comprising:

3. On a metal plate on which a nickel plating layer or graphite dispersed nickel plating layer is formed on the surface, a punching roll provided with a large number of processing protrusions on the outer peripheral surface in the circumferential and longitudinal directions is pressed while rotating on the metal plate. Forming a perforated metal plate having a large number of holes by cutting and raising, and rolling the perforated metal plate together with the cut and raised portion with a rolling stirrer to produce a battery core. Production method.

4. A number of concave portions are formed by pressing a concave roll provided with a large number of processing protrusions on the outer peripheral surface in a circumferential direction and a longitudinal direction while rotating the metal plate, and rolling the metal plate with a rolling roll. Forming a perforated metal plate by forming a hole by fracturing the concave portion to form a perforated metal plate, and forming a nickel plating layer or a graphite dispersed nickel plating layer on the surface of the perforated metal plate.

5. A perforated metal plate having a large number of holes with a return portion is formed by pressing a metal plate while rotating a perforated roll having a large number of processing projections on the outer peripheral surface in the circumferential direction and the longitudinal direction, and turning the roll. Means for folding back the return portion, and Rolling the perforated metal plate with a rolling roll, and thereafter forming a nickel plating layer or a graphite dispersed nickel plating layer on the surface.

6. A punching roll provided with a large number of processing projections in the circumferential direction and longitudinal direction on the outer peripheral surface is pressed while rotating on a metal plate to form a punched metal plate having a large number of holes, and cut and raised. A method for producing a battery core, comprising: rolling the perforated metal plate together with the portion with a rolling roll; and thereafter forming a nickel plating layer or a graphite dispersed nickel plating layer on the surface.