Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/64—Carriers or collectors
  • H01M4/70—Carriers or collectors characterised by shape or form
  • H01M4/72—Grids
  • H01M4/74—Meshes or woven material; Expanded metal
  • H01M4/742—Meshes or woven material; Expanded metal perforated material
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/36—Selection of substances as active materials, active masses, active liquids
  • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/64—Carriers or collectors
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/64—Carriers or collectors
  • H01M4/66—Selection of materials
  • H01M4/661—Metal or alloys, e.g. alloy coatings
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/64—Carriers or collectors
  • H01M4/70—Carriers or collectors characterised by shape or form
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M4/00—Electrodes
  • H01M4/02—Electrodes composed of, or comprising, active material
  • H01M4/64—Carriers or collectors
  • H01M4/70—Carriers or collectors characterised by shape or form
  • H01M4/72—Grids
  • H01M4/74—Meshes or woven material; Expanded metal
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/10—Energy storage using batteries

Definitions

• the present invention relates to an electrode plate material for a secondary battery. More specifically, the present invention relates to an electrode material for a secondary battery having a three-dimensional structure with an increased surface area. Background technology
• an electrode plate of the secondary battery a negative electrode and a positive electrode of a hydrogen battery, a substrate for a Cd battery, and the like can be considered.
• the positive electrode of an N ⁇ -hydrogen battery as a typical example of such an electrode plate of a secondary battery, this includes a sintered electrode and a non-sintered electrode (paste electrode). is there. Since the positive electrode has a lower capacity density than the negative electrode and occupies a larger volume in the battery, there is much room for development for higher capacity.
• a sintered electrode is an electrode in which a sintered layer of powder is formed on a punching metal and filled with an active material mainly composed of Ni hydroxide.
• Sintered electrodes are made by applying a slurry prepared by mixing Ni powder, water, etc., to both surfaces of a punching metal and sintering it at about 1000 ° C. Next, a method of immersing the sintered electrode in an aqueous solution of a nickel salt, and further immersing the electrode in an aqueous solution of nickel salt to convert nickel to nickel hydroxide is generally performed.
• the pore size of the sintered layer is about 10 microns, it has excellent current collecting properties, but its porosity is as low as about 75%, which is disadvantageous for high-density filling of active materials.
• a sponge-like substrate made of nickel has an active material (hydroxide Ni) -filled electrode.
• the paste type electrode is manufactured by mixing an active material powder mainly composed of nickel hydroxide into a paste, filling a substrate, drying, pressing and processing to a predetermined size.
• the foamed polyurethane is processed into a flat shape and a strip shape, then immersed in a turbid solution of carbon powder, dried, and electrically conductive carbon that can be electroplated on the surface of the foamed polyurethane. Attach. After the electroplating of nickel, the polyurethane is burned off and, if necessary, annealed in a reducing atmosphere to produce a foamed nickel substrate.
• Foamed nickel substrates have a high porosity of about 95%, but have the disadvantage of low mechanical strength due to their high porosity.
• the porosity of the foamed nickel substrate is as high as about 95%, but the pore size is as large as 100 to 500 microns, so it is necessary to devise an effective method of collecting the active material.
• non-sintered electrodes are the mainstream as high capacity electrodes. Disclosure of the invention
• an object of the present invention is to provide an electrode plate material for a secondary battery capable of producing a battery with higher output and higher capacity than conventional electrode materials.
• a further object of the present invention is to provide an electrode material for a secondary battery which is easier and cheaper to manufacture than conventional electrode materials and has excellent mechanical strength.
• the present inventors have organized the problems of the prior art in order to achieve the above-described problems.
• the utilization refers to a ratio with respect to a theoretical value of 289 mAh / g assuming that an electron reaction is performed.
• the utilization rate of the sintered electrode is almost 100%, but the non-sintered electrode filled only with the active material powder can obtain only about 65% utilization rate.
• the present inventors have found that when the positive electrode of a secondary battery is formed by using a material obtained by further pressing a punched plate, a significant improvement in characteristics can be obtained. Was completed.
• the electrode plate material according to the present invention can be used not only as a positive electrode but also as a negative electrode material, and can be used, for example, as a negative electrode of a hydrogen secondary battery.
• copper foil is preferable as the negative electrode. That is, a conductive agent and a binder were added to the hydrogen storage alloy powder to form a paste, which was applied to a punched plate and pressed. It was confirmed that the battery using the negative electrode configured in this way reached 80 to 90% of the theoretical value of 372 mAh / g when the capacity was about 300 to 330 mAh / g.
• the present inventors have found that increasing the surface area of the punched plate further improves the battery characteristics, and have completed the present invention.
• the present invention is as follows.
• An electrode material for a secondary battery comprising a punched plate material having a projection on the surface.
• a secondary battery provided with an electrode made of the electrode plate material according to any one of (1) to (7).
• FIG. 1 is a flowchart of a manufacturing process of an electrode plate material according to the present invention.
• FIG. 2 is a schematic explanatory view of a cross-sectional shape of a projection formed in the present invention.
• FIG. 2 (a) shows a waveform
• FIG. 2 (b) shows an uneven shape.
• 3 (a) and 3 (b) are explanatory views of the cross-sectional shapes of the projection and the breakthrough projection formed in the present invention, respectively.
• FIG. 4 (a) is a plan view of the electrode plate material obtained by the example, and FIG. 4 (b) is a cross-sectional view.
• FIG. 5 (a) is a cross-sectional view of an embossed punched plate
• FIG. 5 (b) is a cross-sectional view of a case where a protruding portion is partially cleaved.
• FIG. 1 is a flow chart showing a manufacturing process of an electrode material for a secondary battery according to the present invention.
• Punching is performed by a punching press.
• the punched plate thus obtained may be a steel plate (foil) or a copper plate (foil), and in some cases, a plate material (foil) of other appropriate metal or other material is also conceivable.
• Nickel plating is electroplated and sprayed
• plating by sputtering or plating may be used, electric plating is preferred in view of its economic efficiency.
• it may be a clad material of a steel or copper plate (foil) and a nickel foil. In this specification, such a mode is also referred to as “plating” for convenience.
• plating treatment by nickel plating itself is already known, and further description is omitted.
• the nickel plating may be performed prior to the nonching. From a practical point of view, it is preferable to perform the punching after the punching.
• the thickness of the plating layer at this time is not limited as long as it is realized, since the purpose of providing the plating layer is to provide corrosion resistance, improve conductivity, and make the surface characteristics uniform. Usually, about 1.5 to 5.0 am is sufficient.
• the plated punched plate is further sent to a pressing process, where a process is performed to form a protrusion on only one side or the front and back surfaces.
• the illustrated example shows the case of embossing.
• the shape, number, and size of such projections are not particularly limited, and may be determined according to the target surface area. If possible, it is preferable to provide a projection on the unpunched portion by punching. However, when further increasing the surface area and in order to facilitate the design of the mold, the projection should be formed without considering the punching area. It may be provided. As such press working, for example, as shown in FIG. 1, embossing is performed. In order to secure the strength as an electrode plate, embossing is sometimes preferred. However, when using work hardening during press working, it may be preferable to use breakthrough processing, which will be described later, in which a sufficient working amount can be secured.
• FIG. 2 shows another embodiment of the protruding portion, which may be formed into a cross-sectional shape such as a corrugated shape (see FIG. 2 (a)) or an uneven shape (see FIG. 2 (b)) by pressing.
• the cross-sectional shape at this time includes a corrugated shape, a concave-convex shape, and the like, and the cross-sectional shape may be determined as appropriate depending on the battery characteristics as the electrode plate material.
• the surface area per unit length can be increased by such an aspect, the processing becomes unstable because drawing is not involved unlike embossing.
• a piercing process may be performed in place of the embossing of FIG. A piercing process. Unlike the embossing, such processing does not increase the surface area much, but can enhance the effect of retaining the electrode active material.
• Fig. 3 shows an example of the cross-sectional shape during the break-through processing.
• the case of a simple protrusion (Fig. 3 (a)) and the case of a break-through type protrusion (Fig. 3 (b)) Comparing with the above, the effect of imparting rigidity to the punching plate is large because the degree of work hardening is greater in the case of the breakthrough type projection. However, if burrs remain, problems may remain in the subsequent processing.
• Such projections may be provided on either one of the surfaces of the punching plate.
• the effect of increasing the surface area can be used more effectively.
• the effect becomes more remarkable as a three-dimensional structure.
• the electrode plate material according to the present invention as an electrode, a punching plate can be used, and the protrusions are formed on the surface, and the surface area of the electrode substrate can be particularly increased by embossing From these points, it can be seen that the following excellent effects can be obtained.
• the contact area between the electrode substrate and the active material can be increased, and the conductivity is improved.
• Japanese Patent Application Laid-Open No. 10-106580 discloses an electrode material which is simply embossed.
• This publication states that punched metal, lath nets, and metal screens have low active material holding power.
• punched metal has a porosity of at most 50%.
• This example shows a three-dimensional structure with the following specifications as a cathode material for Ni-hydrogen batteries
• a board was made.
• the specifications of the embossed punched plate in this example are shown below.
• the base material prepared in advance was subjected to a punching press according to the flow shown in FIG.
• Nickel plating was performed by electroplating, and after plating 'annealing', embossing was performed as pressing.
• FIG. 4 (a) is a schematic plan view of the obtained electrode plate
• FIG. 4 (b) is a cross-sectional view. It can be seen that the embossing is performed from the front and back, and is also performed on the punched part.
• the unit of the dimensions in the figure is “mm”.
• the surface area of the electrode plate material was increased by almost 12 G / 0 as compared with the case of a mere punching plate. Since the battery characteristics, such as battery capacity and output, are determined by the surface reactions of the plates, such an increase in surface area results in high capacity and high output, and a simple calculation shows almost a 12% improvement. .
• Fig. 5 (a) is a cross-sectional view of an embossed punched plate.
• the height h is called emboss depth (mm)
• the emboss depth is Above a certain depth, the extreme depth he, some of the embossed feet will split. The depth of the embossed portion at this time becomes the maximum depth (hm).
• the secondary battery constituted by using the electrode material according to the present invention has a specific configuration similar to that of a conventional battery, for example, a conventional Ni-hydrogen secondary battery or a conventional Ni-Cd secondary battery.
• a conventional battery for example, a conventional Ni-hydrogen secondary battery or a conventional Ni-Cd secondary battery.
• significant improvements in battery characteristics are expected.
• an electrode plate material having an increased surface area that is, improved battery characteristics
• a nickel-plated material may be used instead of a conventional nickel material.
• the economic efficiency is greatly improved, and the present invention is an invention having great industrial utility in combination with the improvement of the battery characteristics.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Electrochemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Cell Electrode Carriers And Collectors (AREA)
• Secondary Cells (AREA)
• Battery Electrode And Active Subsutance (AREA)

Priority Applications (3)

Applications Claiming Priority (4)

Publications (1)

Family

ID=27736504

Family Applications (1)

Country Status (6)

Cited By (1)

Families Citing this family (6)

Citations (4)

Family Cites Families (5)

• 2002
  • 2002-06-28 CN CNB021402183A patent/CN1202582C/zh not_active Expired - Fee Related
• 2003
  • 2003-02-13 JP JP2003035187A patent/JP3582524B2/ja not_active Expired - Fee Related
  • 2003-02-14 EP EP03705150A patent/EP1475855A4/en not_active Withdrawn
  • 2003-02-14 WO PCT/JP2003/001538 patent/WO2003069704A1/ja not_active Ceased
  • 2003-02-14 US US10/504,481 patent/US20050164088A1/en not_active Abandoned
  • 2003-02-14 AU AU2003211979A patent/AU2003211979A1/en not_active Abandoned

Patent Citations (4)

Non-Patent Citations (1)

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