Capacitor secondary battery with conductive microparticle deposition current collector layer

Abstract

The present invention provides a large-capacity capacitor secondary battery having a current-collecting layer formed by depositing conductive microparticles. [Solution] Conductive nanoparticles are laminated onto the surface of titanium electrode material. For example, nanocarbon is laminated. A ceramic dielectric is laminated in the middle, and the electrode material is laminated on the other side with nanocarbon particles in between, and a ceramic coating is applied to create a stable laminated structure. Furthermore, nanocarbon fibers are incorporated to significantly improve capacitance, enabling a substantial increase in capacitance and stable product manufacturing and mass production. It is also used in combination with a capacitor to store the power to be supplied to the load, a secondary battery, a charge / discharge control circuit, a DC-DC converter, etc.

Description

Detailed Description of the Invention

Technical Field

[0001] The present invention relates to an improvement of a large-capacity capacitor device provided with a current collecting layer at the interface between a first and a second electrode and a dielectric layer, and a secondary battery using the improved capacitor device.

Background Art

[0002] The following patent documents are available as the prior art of the large-capacity capacitor device as described above.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the large-capacity capacitor device as described above, increasing the capacity is a common problem. The present invention aims to provide a large-capacity capacitor device having a current collecting layer with a novel structure to solve this problem.

Means for Solving the Problems

[0005] The present invention according to claim 1 is a large-capacity capacitor device in which a dielectric layer is sandwiched between a first and a second electrode, and a current collecting layer is provided at the interface between the first and second electrodes and the dielectric layer. The current collecting layer has a structure in which micro-sized conductive particles and carbon nanofibers are three-dimensionally interconnected by fusion, and the structure is coated and included with ceramic. Furthermore, the dielectric is a material selected from ceramics, a mixture of ceramic fine powder and plastic, or plastic according to the application.

[0006] Furthermore, the present invention relates to a secondary battery comprising the capacitor device and a charge / discharge control circuit. [Effects of the Invention]

[0007] This invention can provide a high-capacity capacitor device. [Brief explanation of the drawing]

[0008] [Figure 1] (a) is a basic configuration diagram of one embodiment, and (b) is a schematic cross-sectional view of the current collector layer. (c) is a configuration diagram of the capacitor unit including the current collector layer. [Figure 1A] (a) and (b) are schematic cross-sectional views of other examples of current collector layers. [Figure 2] This is a basic configuration diagram of another example of an embodiment incorporating nanocarbon fibers. [Figure 3] (a) is a basic diagram of a capacitor unit, and (b) is a basic diagram of a secondary battery. [Figure 4] This is a basic circuit diagram for a rechargeable battery. [Figure 5] This is a diagram illustrating the charge and discharge characteristics of a secondary battery. [Modes for carrying out the invention]

[0009] Figure 1(a) is a basic configuration diagram of one embodiment of the present invention. The capacitor device A of this embodiment has a basic configuration in which a dielectric layer 3 is sandwiched between first and second electrodes 1, 1, and current collecting layers 2, 2 are provided at the interface between the first and second electrodes 1, 2 and the dielectric layer 3, and is formed on one side of an insulating sheet substrate 4. The current collecting layers 2, 2 consist of micro and pico-sized conductive fine particles 2a that are interconnected in three dimensions, and also include nano and pico-sized carbon fibers that are interconnected, with voids 2d between the conductive fine particles 2a. These voids 2d are filled with a predetermined gas. The first and second electrodes 1, 1 and the conductive fine particles 2a of the current collecting layers 2, 2 are electrically connected. The dielectric layer 3 is made of a ceramic such as barium titanate, or a mixture of ceramic fine powder and plastic, or plastic alone. The terms "micro-size" and "pico-size" used herein refer to a maximum three-dimensional dimension of the conductive fine particles 2a that is less than 1 millimeter and greater than or equal to 1 nanometer. Furthermore, the gas may be air, or a specific gas used in the manufacturing process of the current collector layers 2, 2. In short, it is sufficient that the gaps between the conductive fine particles 2a are filled with some kind of gas, rather than a solid or liquid. The first and second electrodes 1, 1 are made of metals such as titanium, copper, nickel, or alloys thereof, and are connected to output lead wires 5, 5.

[0010] Figure 1(b) is a schematic cross-sectional view of the current collector layer. As shown in this figure, the current collector layer 2 has a three-dimensional network structure in which micro and pico-sized conductive fine particles and fibers 2a are interconnected in three dimensions, and the voids 2d between the conductive fine particles and fibers 2a are filled with a predetermined gas. In this example, the conductive fine particles 2a are solid carbon or These are metal nanoparticles. There are no particular restrictions on the carbon and metal that form the nanoparticles; they may be the same as or different from the metals that form the first and second electrodes 1, 1. However, it is desirable that the metal has electrical conductivity equal to or better than that of the first and second electrodes 1, 1. Current collector layers 2, 2 using such carbon and metal nanoparticles can be formed by sputtering. That is, by rapidly solidifying metal vapor into fine particles on a substrate (e.g., a dielectric layer), current collector layers 2, 2 can be formed in a laminated form on the substrate, i.e., as sputtering-formed layers. Alternatively, a mixture of carbon, metal fine particles, a fibrous substrate, and a binder resin can be formed into a sheet (green sheet) by pressing or extruding, and then heated to near the melting point of the metal to eliminate the binder resin and fuse the metal fine particles together, thereby forming sheet-like current collector layers 2, 2. To add a little more detail about the manufacturing method of capacitor device A, the first and second electrodes 1,1 and dielectric layers 2,2 can all be made from pre-prepared sheets, or they can be formed on a substrate in a predetermined order by lamination or the like.

[0011] This invention focuses on the current collector layers 2, 2 with the unique structure described above, and provides the following effects. Furthermore, this invention does not impose any restrictions on anything other than the current collector layers 2, 2, i.e., the first and second electrodes 1, 1, dielectric layers, etc., and can be widely applied to various capacitor devices having electrodes and dielectric layers with diverse configurations. According to the present invention, the three-dimensional network structure formed on the current collector layers 2, 2 is a continuum of micro and pico-sized fine carbon and metal fragments and thin films, and therefore has a huge surface area relative to its volume. By electrically connecting such a three-dimensional network structure of carbon and metal to the first and second electrodes 1, 1, the surface area of ​​the first and second electrodes 1, 1 is dramatically increased, thereby increasing the capacitance of the capacitor device A.

[0012] Figure 2 is a basic configuration diagram of another embodiment in which nanocarbon fibers are mixed. This embodiment is formed by stacking multiple capacitor devices A from the above embodiment in parallel. Each of the parallelized capacitor devices A is the same as in the embodiment described above. This parallelization by multiple stacking allows for an even larger capacitance of the capacitor devices A.

[0013] Figure 3 (a) and (b) are respectively basic configuration diagrams of a capacitor unit and a secondary battery. Also, FIG. 4 is a basic circuit diagram of the secondary battery, and FIG. 5 is a charge / discharge characteristic diagram of the secondary battery. This capacitor unit has a configuration in which the capacitor device A shown in FIG. 1(a) is multi-cylindrically wound. With such a configuration, a large-capacity and small-sized capacitor unit can be obtained. The secondary battery B is configured to include two or more capacitor devices A and a charge / discharge control circuit C. The charge / discharge control circuit C is a device that makes the rapid charging and rapid discharging, which are general characteristics of capacitors, gentle like those of general secondary batteries, and can be composed of a DC-DC converter or the like. Such a secondary battery B can replace conventional lead, nickel-cadmium storage batteries, lithium-ion storage batteries, etc. Note that a secondary battery B may be configured by combining the capacitor device A shown in FIG. 2 and the charge / discharge control circuit C as described above.

[0014] Also, according to the present invention, by magnetizing or superconducting the metal used for the current collecting layer 2, that is, by enhancing the electron fluidity of the current collecting layer 2, further high performance of the capacitor device A and the secondary battery B can be expected.

Explanation of Reference Numerals

[0015] A Capacitor device B Secondary battery C Charge / discharge control circuit 1 Electrode 2 Current collecting layer 2a Conductive fine particles 2b Nano-picocarbon fiber 2c Ceramic coating 3 Dielectric layer 4 Insulating sheet base material

Claims

1. In a large-capacity capacitor device in which a dielectric layer is sandwiched between first and second electrodes, and a current collector layer is provided at the interface between the first and second electrodes and the dielectric layer, Regarding the lamination of conductive material nanoparticles in current collectors, the coating with a non-conductive material such as ceramic is used to prevent disorder and dispersion of the conductive material nanoparticle lamination structure caused by pressure compression and bending. The current collecting layer is characterized by having a structure in which nanocarbon particles and nano-sized carbon fibers are composite-laminated on the surface of a titanium electrode, and are interconnected three-dimensionally by ceramic coating and fusion, with voids between the conductive nanoparticles.

2. In a large-capacitance capacitor device in which a dielectric layer is sandwiched between first and second electrodes, and a current collector layer is provided at the interface between the first and second electrodes and the dielectric layer, the capacitance is significantly increased by compounding nano and pico carbon fibers into the conductive material nanoparticle laminate of the current collector. The dielectric is characterized by being a material selected from a mixture of ceramic and ceramic fine powder and plastic, or from plastic alone.

3. In claim 1 or 2, The large-capacity capacitor device is characterized in that it is formed on one side of an insulating sheet substrate and is wound in multiple cylindrical sections to form a cylindrical capacitor unit.

4. In claim 1 or 2, The aforementioned large-capacity capacitor device is a large-capacity capacitor device that is stacked in multiple layers and connected in parallel.

5. A secondary battery comprising a large-capacity capacitor device according to any one of claims 1 to 4 and a charge / discharge control circuit.

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