JP5212906B2 - Whisker forming body, electrode for electrochemical device, and production method thereof - Google Patents

Description

The present invention relates to a whisker-forming body, an electrode for an electrochemical device, and a method for producing the same, and more specifically, a predetermined whisker base material layer disposed on a predetermined base material, and the whisker base material layer. The present invention relates to a whisker-forming body having a whisker-forming layer formed of predetermined whiskers disposed on the electrode, an electrode for an electrochemical device to which the whisker-forming body is applied, and a manufacturing method thereof.
Moreover, the electrode for electrochemical devices can be used suitably for electrochemical devices, such as a lithium ion battery, a redox capacitor, a gas sensor, and a solar cell.
Furthermore, these electrochemical devices can be combined with other components into modules.
Furthermore, these electrochemical devices and modules can be suitably used for moving bodies such as automobiles, motorcycles, railways, airplanes, and ships.

  Conventionally, as a method for producing high-purity, large-sized and uniform-shaped tin dioxide whiskers with high efficiency, in a reaction furnace in which a gas containing oxygen is supplied from outside the system by forced feeding or the like, metallic tin is contained in the reaction furnace. A crucible for evaporating the raw material is disposed, and the raw material is supplied to the crucible, and tin vapor exists while maintaining the temperature range of 1000 ° C. to 1350 ° C. in which the tin vapor is generated in the reaction furnace. A method for producing a tin dioxide whisker in which an inert gas is intermittently fed into the atmosphere has been proposed (see Patent Document 1).

Japanese Patent Laid-Open No. 5-17145

As a method for producing highly conductive fibrous conductive tin oxide (IV) with a high yield in a relatively short time, a mixture of a tin compound, an antimony compound, and a reducing agent is heated at a predetermined temperature in a crucible. In the manufacturing method of fibrous conductive tin oxide (IV) in which SnO gas is generated, saturated, and oxidized to precipitate and grow fibrous conductive SnO ₂ , theoretically from the mixture introduced into the crucible When the maximum number of moles of SnO that can be produced is A mole, the crucible volume is Bcc, the crucible opening area is C square cm, and the crucible heating temperature is D ° C., X = C × 10 ¹⁰ / {AB (D -1000) ³ } A manufacturing method of fibrous conductive tin (IV) oxide is proposed in which the crucible is heated so that the opening ratio X defined by ³ } is maintained at 300 or less (see Patent Document 2).

Japanese Patent Laid-Open No. 6-172099

  On the other hand, a whisker-forming body in which whiskers are formed on the surface of a raw material substrate, the raw material substrate comprising at least one selected from the group consisting of metals, alloys and ceramics, the whisker Is an inert gas comprising a whisker-forming body comprising an oxide of at least one element contained in the raw material substrate, and a raw material substrate comprising at least one member selected from the group consisting of metals, alloys and ceramics. There has been proposed a method for manufacturing a whisker forming body in which a whisker composed of an oxide of at least one element contained in the raw material substrate is formed on the surface of the raw material substrate by heat treatment in an atmosphere and in the presence of a trace amount of oxygen. (See Patent Document 3).

JP 2006-1826 A

However, the tin dioxide whisker manufacturing method and the fibrous conductive tin oxide (IV) manufacturing method described in Patent Document 1 and Patent Document 2 are not appropriate as methods for causing whiskers to grow densely on the surface of the substrate. Moreover, there is a problem that it is difficult to form whiskers on the surface of the base material other than tin.
Furthermore, in the manufacturing method of the whisker formation body of the said patent document 3, although the densely formed whisker can be formed in the tin surface or the surface of the alloy containing tin, it is uniform in base materials other than tin. In order to form densely formed whiskers, the base material must be alloyed, and there is a problem that the form of the base material is restricted. Furthermore, a method of forming a film on the surface of the base material is also conceivable, but there are problems with the contact between the base material and the whisker-forming layer, such as the uniformity of the coating of the film on the surface and cracks and peeling that occur during heat treatment. There is.

  The present invention has been made in view of such problems of the prior art, and an object thereof is to provide a predetermined whisker base material layer disposed on a predetermined base material, and the whisker base material. It is an object of the present invention to provide a whisker-forming body having a whisker-forming layer formed of predetermined whiskers disposed on the layer, an electrode for an electrochemical device formed by applying the whisker-forming body, and a method for producing the same.

The inventors of the present invention have made extensive studies to achieve the above object.
As a result, a precursor layer containing tin or zinc as a precursor of the whisker base material layer is formed, and then the precursor layer is melted in an inert atmosphere, and the melted precursor layer is further dissolved in a trace oxygen atmosphere. It was found that the above-mentioned object can be achieved by heating the precursor layer, and then heating the precursor layer at a higher temperature in a trace oxygen atmosphere, thereby completing the present invention.

That is, the whisker-forming body of the present invention comprises a base material, a whisker base material layer disposed on the surface of the base material, and a whisker-forming layer formed of whiskers disposed on the surface of the whisker base material layer. And the whisker of the whisker forming layer is made of an oxide of tin or zinc , the whisker base material layer contains the tin or zinc , and the base material has a melting point higher than that of tin or zinc. It is a predetermined base material having a melting point.

  Moreover, the electrode for electrochemical devices of the present invention is characterized by applying the whisker forming body of the present invention.

Furthermore, the manufacturing method of the whisker forming body or the electrode for an electrochemical device of the present invention is the manufacturing method of the whisker forming body of the present invention or the electrode for an electrochemical device of the present invention, and includes the following steps (1) to (1) to (4) is included.
(1) A step of forming a precursor layer containing tin or zinc serving as a precursor of a whisker base material layer (2) A step that is performed after the step (1) and melts the precursor layer in an inert atmosphere (3) Performed after the step (2) and heating the melted precursor layer in a trace oxygen atmosphere (4) Performed after the step (3) and the precursor layer in a trace oxygen atmosphere And heating at a higher temperature than the step (3)

  Moreover, the lithium ion battery of this invention has the electrode for electrochemical devices of the said invention, It is characterized by the above-mentioned.

  Furthermore, the redox capacitor of this invention has the electrode for electrochemical devices of the said invention, It is characterized by the above-mentioned.

  Moreover, the gas sensor of this invention has the electrode for electrochemical devices of the said invention, It is characterized by the above-mentioned.

  Furthermore, the solar cell of the present invention has the electrode for an electrochemical device of the present invention, and the base material of the electrode has translucency.

  The module of the present invention includes the lithium ion battery of the present invention, the redox capacitor of the present invention, the gas sensor of the present invention, or the solar battery of the present invention.

  Furthermore, the mobile body of the present invention includes the lithium ion battery of the present invention, the redox capacitor of the present invention, the gas sensor of the present invention, the solar cell of the present invention, or the module of the present invention. .

According to the present invention, a precursor layer containing tin or zinc serving as a precursor of the whisker base material layer is formed, and then the precursor layer is melted in an inert atmosphere. Heating in a trace oxygen atmosphere, and then heating the precursor layer at a higher temperature in a trace oxygen atmosphere, the base material and the whisker base material layer disposed on the surface of the base material And a whisker forming layer formed of whiskers disposed on the surface of the whisker base layer, the whisker of the whisker forming layer is made of an oxide of tin or zinc , and the whisker base layer is A whisker-forming body comprising tin or zinc and the base material having a melting point higher than that of tin or zinc , an electrode for an electrochemical device formed by applying the whisker-forming body, and a method for producing the same To provide It can be.

  Hereinafter, whisker formers according to an embodiment of the present invention, electrodes for electrochemical devices, manufacturing methods thereof, electrochemical devices such as lithium ion batteries, redox capacitors, gas sensors, solar cells using the electrodes for electrochemical devices, A module using an electrochemical device and a mobile body using the electrochemical device and module will be described in detail.

First, the whisker former according to one embodiment of the present invention will be described in detail.
The whisker forming body of this embodiment includes a base material, a whisker base material layer disposed on the surface of the base material, and a whisker forming layer formed of whiskers disposed on the surface of the whisker base material layer. It is what has.
And the whisker of this whisker forming layer consists of a compound of metal A whose melting point of a simple substance is 300 [K] or more and 1000 [K] or less, this whisker base material layer contains metal A, and such a substrate is It has a melting point higher than that of metal A.
By setting it as such a structure, a desired whisker formation body can be obtained.
Here, “whisker” refers to a fibrous or needle-like structure having an aspect ratio of 5 or more or 10 or more.

When the melting point of the metal A is 1000 [K] or less, the metal A can be melted during the formation of the whisker, the surface coverage is improved, and even if there is a crack or the like, the substrate It is possible to cover the surface. Therefore, a desired whisker forming body can be obtained. In addition, a metal that melts near room temperature such that the melting point of the metal A is less than 300 [K] is difficult to handle, and a desired whisker forming body cannot be obtained.
The whisker base material layer is composed of metal A or the like melted during whisker formation. Therefore, the whisker base material layer and the whisker have substantially the same composition. Furthermore, the base material needs to have a melting point higher than the melting point of the metal A because it is necessary not to melt during the formation of the whisker base material layer.

The compound of metal A is not particularly limited, but for example, it is desirable to have conductivity. In the case of conductivity, it is possible to control the oxidizing atmosphere and reducing atmosphere on the surface, to detect these, and to improve the applicability. For example, application to electrochemical devices such as gas sensors and batteries becomes possible.
The conductivity range is not particularly limited as long as the conductivity is equal to or higher than that of a semiconductor. For example, a resistance of 100000 Ωcm or less is preferable.

  Further, the metal A is not particularly limited, but it is desirable that the metal A can take a plurality of oxidation states, for example. The metal A that can take a plurality of oxidation states easily causes an oxidation-reduction reaction, and can be suitably used for a catalyst or an electrode.

  Further, the compound of metal A is not particularly limited, and examples thereof include metal oxides. The whisker of the metal A oxide can be produced relatively easily by bringing an oxygen stream into contact with the metal A, for example.

Furthermore, the compound of the metal A is not particularly limited, but for example, tin (Sn), antimony (Sb), zinc (Zn), indium (In), lead (Pb) or selenium (Se). Examples thereof include mixed oxides or complex oxides according to oxides or any combination thereof.
These metal oxides are particularly desirable because they have the above-described performance and can be suitably used for electrodes.

On the other hand, the substrate is not particularly limited, and for example, a plate-like body such as a foil can be applied.
When such a substrate is used, mass production can be performed at a relatively low cost.

The substrate is not particularly limited, and examples thereof include porous bodies such as a mesh body, a foamed body, and a punching processed body. These can be used individually by 1 type or in combination of multiple types.
Such a base material can increase a specific surface area and can improve functionality.

Next, the electrode for an electrochemical device according to an embodiment of the present invention will be described in detail.
The electrode for an electrochemical device of this embodiment is formed by applying the above-described whisker forming body according to one embodiment of the present invention.
By setting it as such a structure, the high performance electrode for electrochemical devices can be obtained.

The whiskers constituting the whisker forming layer in the electrode for an electrochemical device can be obtained in a larger amount than in the past by a method for producing a whisker forming body according to an embodiment of the present invention described later in detail. Therefore, it is possible to increase the surface area as an electrode, and the sensitivity is improved. In addition, by applying a conductive whisker, it is not necessary to use a conductive auxiliary agent or a binder, diffusion within the electrode occurs very quickly, and the reactivity is improved. Furthermore, in the case of an electrode that causes an oxidation-reduction reaction, diffusion in a solid usually becomes resistance. However, the electrode for an electrochemical device according to the present embodiment has a short diffusion distance in solid, so that the resistance can be lowered. .
As described above, by applying the above-described whisker forming body according to the embodiment of the present invention, an electrode for an electrochemical device having an extremely small resistance component can be obtained.

Although a base material is not specifically limited, For example, it is desirable to have electroconductivity.
The conductivity range is not particularly limited as long as it has a conductivity higher than that of a semiconductor. For example, the resistance is preferably 100,000 Ωcm or less, and more preferably 1 Ωcm or less.

Further, the base material is not particularly limited. For example, the base material does not cause oxidation and reduction reaction at the operating potential of the electrochemical device electrode and does not cause reaction with the electrolyte of the electrochemical device. It is desirable.
By adopting such a configuration, for example, expansion, contraction, dissolution and the like hardly occur, and the electrode has excellent durability.

Further, the substrate is not particularly limited, but for example, one containing nickel (Ni), chromium (Cr), cobalt (Co), tungsten (W), iron (Fe) or manganese (Mn), or The compound or mixture which concerns on these arbitrary combinations can be mentioned.
Such a substrate is desirable because it has a particularly high melting point and low resistance.

On the other hand, the substrate is not particularly limited, but for example, it is desirable to have translucency.
For example, a dye-sensitized solar cell can be mentioned as a kind of electrochemical device, but also in the present invention, it can be realized by making the substrate transparent. Since the dye can be supported on a wide surface and the diffusion of the electrolyte is not hindered, a large current, high output solar cell can be obtained.
In addition, as such a base material, oxides, such as indium (In), tin (Sn), zinc (Zn), calcium (Ca), can be mentioned, for example.

Next, the manufacturing method of the whisker formation body or electrode for electrochemical devices of this invention is demonstrated in detail.
The manufacturing method of the whisker forming body or the electrode for an electrochemical device according to the present embodiment is the manufacturing method of the whisker forming body according to the above-described embodiment of the present invention or the electrochemical device electrode according to the above-described embodiment of the present invention. And it is a manufacturing method including the following process (1)-(4).
(1) A step of forming a precursor layer containing metal A as a precursor of a whisker base material layer (2) A step of performing the step (1) after melting the precursor layer in an inert atmosphere (3) Performed after step (2), heating the molten precursor layer in a trace oxygen atmosphere (4) Performed after step (3), and the precursor layer is higher in the trace oxygen atmosphere than step (3) Heating process at temperature

By setting it as such a procedure, the desired whisker formation body and the electrode for electrochemical devices with high adhesiveness and uniformity can be obtained.
Hereinafter, an example of the manufacturing method of the whisker formation which concerns on one Embodiment of this invention is demonstrated concretely for every process.

First, in step (1), a precursor layer containing metal A, which is a precursor of a whisker base material layer, is formed on a substrate by, for example, chemical vapor deposition (CVD) or physical vapor deposition (PVD). To do.
In addition, since the metal A becomes a raw material of a whisker to be formed later, a precursor layer containing the metal A as a main component can be suitably used.
Here, the “main component” means that the mass percentage in the total amount of the constituent members (for example, the precursor layer) is 50% by mass or more.

Next, in the step (2), for example, the precursor layer is melted by heating or the like under an inert atmosphere such as argon to spread the metal A on the surface of the base material.
Note that the inert gas that forms the inert atmosphere is not limited to argon. For example, a mixed gas of nitrogen, helium, neon, krypton, xenon, or radon, and any combination thereof may be used. it can.
Further, the heating temperature is not particularly limited as long as it is lower than the melting point temperature of the substrate and higher than the melting point of the metal A, but it is, for example, 200 to 2000 ° C, preferably 200 to 800 ° C.

Further, in the step (3), whisker growth nuclei are formed on the surface of the liquid metal A by heating in an atmosphere containing a trace amount of oxygen of 1% by volume or less, for example.
The “trace oxygen” can be a raw material for the formed whisker, and is not particularly limited as long as a desired whisker-forming layer is obtained. However, for example, 1 to 10,000 ppm is preferable.

Thereafter, in step (4), the growth of whiskers is promoted by heating at a higher temperature than in step (3) in an atmosphere containing a trace amount of oxygen of 1% by volume or less, and predetermined whiskers are formed on the surface of the substrate. A base material layer and a whisker forming layer are formed to obtain a desired whisker forming body.
In addition, about a process (3) and a process (4), it can also carry out as a continuous temperature rising process.

Next, a lithium ion battery according to an embodiment of the present invention will be described in detail.
The lithium ion battery according to this embodiment has the electrode for an electrochemical device according to one embodiment of the present invention described above.
With such a configuration, resistance factors such as the electrode-electrolyte interface, electrolyte internal diffusion, and solid diffusion in the lithium ion battery can be greatly improved, and a high-power lithium ion battery can be obtained.

Next, a redox capacitor according to an embodiment of the present invention will be described in detail.
The redox capacitor according to this embodiment has the electrode for an electrochemical device according to one embodiment of the present invention described above.
With such a configuration, resistance factors such as an electrode-electrolyte interface and electrolyte internal diffusion in the redox capacitor can be greatly improved, and a high-power redox capacitor can be obtained.

Next, a gas sensor according to an embodiment of the present invention will be described in detail.
The gas sensor which concerns on this embodiment has the electrode for electrochemical devices which concerns on one Embodiment of this invention mentioned above.
By adopting such a configuration, it is possible to detect a resistance change due to adsorbed molecules on the surface with high sensitivity, and it is possible to obtain a highly sensitive gas sensor.

Next, a solar cell according to an embodiment of the present invention will be described in detail.
The solar cell according to this embodiment has the electrode for an electrochemical device according to one embodiment of the present invention described above.
With such a configuration, resistance factors such as the electrode-electrolyte interface and electrolyte internal diffusion in the solar cell can be greatly improved, and a high-output solar cell can be obtained.

Next, a module according to an embodiment of the present invention will be described in detail.
The module according to the present embodiment includes the above-described lithium ion battery, redox capacitor, gas sensor, or solar battery according to an embodiment of the present invention.
With such a configuration, a module with high output or high sensitivity can be obtained.

Next, the moving body according to the embodiment of the present invention will be described in detail.
The moving body according to the present embodiment includes the above-described lithium ion battery, redox capacitor, gas sensor, solar cell, or module according to the embodiment of the present invention.
With such a configuration, a high-power lithium-ion battery, redox capacitor, solar battery, or highly sensitive gas sensor, or a module having these, can be used for rapid energy consumption and regenerative movement. You can get a body.

  Hereinafter, the present invention will be described in more detail with reference to some examples and comparative examples.

(Example 1-1)
<Preparation of whisker forming body>
A tin precursor layer (thickness 20 μm), which is a precursor of the whisker base layer, was formed by plating on a nickel plate (thickness 100 μm) as a base material.
Next, the base material on which the precursor layer was formed was placed in an electric furnace capable of controlling the atmosphere, and heated to 400 ° C. at a rate of temperature increase of 20 ° C./min in an argon stream.
Subsequently, it heated to 800 degreeC with the temperature increase rate of 20 degree-C / min in oxygen-containing argon (oxygen concentration: 400 ppm) airflow, and also hold | maintained at 800 degreeC for 1 hour.
Thereafter, it was naturally cooled to room temperature to obtain a whisker-forming body of this example.

The whisker forming body of this example was observed with a scanning electron microscope (SEM). SEM photographs are shown in FIGS. 1 (a) and (b). Note that FIG. 1B shows an enlargement ratio higher than that in FIG.
Moreover, the whisker former of this example was evaluated by energy dispersive X-ray fluorescence analysis (EDX). The EDX analysis diagrams are shown in FIGS. 2A is an EDX analysis chart of tin (Sn) distribution, FIG. 2B is an EDX analysis chart of oxygen (O) distribution, and FIG. 2C is a nickel (Ni) distribution chart. It is an EDX analysis figure.

From FIG. 1A and FIGS. 2A to 2C, it can be seen that the surface is covered with Sn and O even if some cracks are present, and Ni of the base material is not exposed.
Moreover, FIG.1 (b) shows that the base-material surface is covered with the tens of nm whisker.

<Production of lithium ion battery>
Furthermore, a lithium ion battery was produced by the following operation using the whisker former of this example as an electrode for an electrochemical device.
As a negative electrode, a metal lithium plate (thickness: 100 μm) punched out with a diameter of 16 mm was prepared.
Moreover, what punched out the electrode for electrochemical devices of this example by (phi) 15mm was prepared as a positive electrode.
Furthermore, quartz filter paper (thickness 300 μm) was prepared as a separator.
Furthermore, an electrolytic solution prepared by dissolving lithium tetrafluoroborate (LiBF ₄ ), which is a lithium salt, at a concentration of 1 mol / L in an equal volume mixture of ethylene carbonate and propylene carbonate was prepared.
These were sealed in a 2032 type coin cell to obtain a lithium ion battery of this example.

(Example 1-2)
<Preparation of whisker forming body>
A zinc precursor layer (thickness: 20 μm) serving as a whisker base material layer precursor was formed on a nickel foam (thickness: 500 μm) as a base material by plating.
Next, the base material on which the precursor layer was formed was placed in an electric furnace capable of controlling the atmosphere, and heated to 400 ° C. at a rate of temperature increase of 20 ° C./min in an argon stream.
Subsequently, it heated to 800 degreeC with the temperature increase rate of 20 degree-C / min in oxygen-containing argon (oxygen concentration: 400 ppm) airflow, and also hold | maintained at 800 degreeC for 1 hour.
Thereafter, it was naturally cooled to room temperature to obtain a whisker-forming body of this example.

  The whisker forming body of this example was observed with SEM. A SEM photograph is shown in FIG.

<Production of lithium ion battery>
Furthermore, a lithium ion battery was produced by the following operation using the whisker former of this example as an electrode for an electrochemical device.
As a negative electrode, a metal lithium plate (thickness: 100 μm) punched out with a diameter of 16 mm was prepared.
Moreover, what punched out the electrode for electrochemical devices of this example by (phi) 15mm was prepared as a positive electrode.
Furthermore, quartz filter paper (thickness 300 μm) was prepared as a separator.
Furthermore, an electrolytic solution prepared by dissolving lithium tetrafluoroborate (LiBF ₄ ), which is a lithium salt, at a concentration of 1 mol / L in an equal volume mixture of ethylene carbonate and propylene carbonate was prepared.
These were sealed in a 2032 type coin cell to obtain a lithium ion battery of this example.

(Comparative Example 1-1)
<Preparation of whisker forming body>
A tin precursor layer (thickness 20 μm), which is a precursor of the whisker base layer, was formed by plating on a nickel plate (thickness 100 μm) as a base material.
Next, the base material on which the precursor layer was formed was placed in an electric furnace capable of controlling the atmosphere, and heated to 800 ° C. at a heating rate of 20 ° C./min in an argon stream.
Subsequently, it hold | maintained at 800 degreeC for 1 hour in oxygen containing argon (oxygen concentration: 400 ppm) airflow.
Thereafter, it was naturally cooled to room temperature to obtain a whisker-forming body of this example. In addition, in the whisker formation body of this example, it confirmed that the whisker was not formed.

<Production of lithium ion battery>
Furthermore, the same operation as the production of the lithium ion battery of Example 1-1 was repeated except that the whisker-forming body of this example was used as an electrode for an electrochemical device, to obtain a lithium ion battery of this example.

(Comparative Example 1-2)
<Preparation of whisker forming body>
A zinc precursor layer (thickness: 20 μm) serving as a whisker base material layer precursor was formed on a nickel foam (thickness: 500 μm) as a base material by plating.
Next, the base material on which the precursor layer was formed was placed in an electric furnace capable of controlling the atmosphere, and heated to 800 ° C. at a heating rate of 20 ° C./min in an argon stream.
Subsequently, it hold | maintained at 800 degreeC for 1 hour in oxygen containing argon (oxygen concentration: 400 ppm) airflow.
Thereafter, it was naturally cooled to room temperature to obtain a whisker-forming body of this example. In addition, in the whisker formation body of this example, it confirmed that the whisker was not formed.

<Production of lithium ion battery>
Furthermore, the same operation as the production of the lithium ion battery of Example 1-2 was repeated except that the whisker-forming body of this example was used as an electrode for an electrochemical device, to obtain a lithium ion battery of this example.

(Comparative Example 1-3)
<Preparation of whisker forming body>
A tungsten precursor layer (thickness 20 μm) serving as a whisker base layer precursor was formed on a nickel plate-like body (thickness 100 μm) as a base material by plating.
Next, the base material on which the precursor layer was formed was placed in an electric furnace capable of controlling the atmosphere, and heated to 400 ° C. at a rate of temperature increase of 20 ° C./min in an argon stream.
Subsequently, it heated to 800 degreeC with the temperature increase rate of 20 degree-C / min in oxygen-containing argon (oxygen concentration: 400 ppm) airflow, and also hold | maintained at 800 degreeC for 1 hour.
Thereafter, the sample was naturally cooled to room temperature to obtain a sample of this example. In the sample of this example, an oxide layer was present on the surface, but it was confirmed that no whiskers were formed.

<Production of lithium ion battery>
Furthermore, the same operation as the production of the lithium ion battery of Example 1-1 was repeated except that the whisker-forming body of this example was used as an electrode for an electrochemical device, to obtain a lithium ion battery of this example.

[Performance evaluation]
The lithium ion batteries of the above examples were evaluated by a cyclic voltammetry test. Specifically, the maximum current was measured when scanning was performed at a potential range of 0.5 to 2.5 V vs Li / Li ⁺ at 10 mV / second. The obtained results are shown in Table 1.

From Table 1, the lithium ion batteries of Examples 1-1 and 1-2 belonging to the scope of the present invention are compared with the lithium ion batteries of Comparative Examples 1-1 to 1-3 outside the present invention. It can be seen that the maximum current is remarkably high.
Therefore, it can be seen that the electrode for an electrochemical device formed by applying the whisker forming body of the present invention is an electrode that can provide a high-power lithium ion battery when applied to a lithium ion battery.

( Reference Example 2-1)
<Preparation of whisker forming body>
On a glass substrate (size: 10 × 10 × 1 mm) with a fluorine-doped tin oxide layer (thickness 100 μm) as a base material, a zinc precursor layer (thickness 20 μm) that becomes a precursor of a whisker base layer by plating Formed.
Next, the base material on which the precursor layer was formed was placed in an electric furnace capable of controlling the atmosphere, and heated to 400 ° C. at a rate of temperature increase of 20 ° C./min in an argon stream.
Subsequently, it heated to 800 degreeC with the temperature increase rate of 20 degree-C / min in oxygen-containing argon (oxygen concentration: 400 ppm) airflow, and also hold | maintained at 800 degreeC for 1 hour.
Thereafter, it was naturally cooled to room temperature to obtain a whisker-forming body of this example.

<Production of solar cell>
Furthermore, a solar cell was produced by the following operation using the whisker-forming body of this example as an electrode for an electrochemical device.
The electrode for an electrochemical device of this example was put into a solution in which 1 mmol / L EosinY dye (manufactured by Aldrich) was dissolved in ethanol. Then, immersion and drying were repeated 5 times, and further, heat treatment was performed at 100 ° C. Was adsorbed. In addition, a 20 μm platinum foil was stacked on the 1 mm width of this electrode to form a current extraction terminal.
Further, a counter electrode was prepared by punching a platinum plate (thickness: 100 μm) with a diameter of 20 mm.
Furthermore, quartz filter paper (thickness 300 μm) was prepared as a separator.
Furthermore, an electrolyte solution prepared by dissolving 0.05 mmol / L iodine and 0.5 mmol / L lithium iodide in propylene carbonate was prepared.
The liquid injection was impregnated into a separator to obtain a solar cell of this example as an open cell.

(Comparative Example 2-1)
<Preparation of whisker forming body>
On a glass substrate (size: 10 × 10 × 1 mm) with a fluorine-doped tin oxide layer (thickness 100 μm) as a base material, a zinc precursor layer (thickness 20 μm) that becomes a precursor of a whisker base layer by plating Formed.
Next, the base material on which the precursor layer was formed was placed in an electric furnace capable of controlling the atmosphere, and heated to 800 ° C. at a heating rate of 20 ° C./min in an argon stream.
Subsequently, it hold | maintained at 800 degreeC for 1 hour in oxygen containing argon (oxygen concentration: 400 ppm) airflow.
Thereafter, the sample was naturally cooled to room temperature to obtain a sample of this example. In the sample of this example, an oxide layer was present on the surface, but it was confirmed that no whiskers were formed.

<Production of solar cell>
Furthermore, except having used the whisker formation body of this example as an electrode for electrochemical devices, operation similar to preparation of the solar cell of Reference Example 2-1 was repeated, and the solar cell of this example was obtained.

[Performance evaluation]
The short circuit current was measured by irradiating 100 mW / cm ² of artificial sunlight on the electrode side for an electrochemical device to which the whisker forming body in the solar cell of each of the above examples was applied. The obtained results are shown in Table 2.

From Table 2, the solar cell of Example 2-1, as compared to the solar cell ratio Comparative Examples 2-1, it can be seen that the short-circuit current is significantly higher.

  As mentioned above, although this invention was demonstrated with some embodiment and an Example, this invention is not limited to these, A various deformation | transformation is possible within the range of the summary of this invention.

It is a SEM photograph (a) and (b) of the whisker formation body of Example 1-1. It is an EDX analysis figure (a)-(c) in Example 1-1. It is a SEM photograph of the whisker formation object of Example 1-2.

Claims (14)

A base material or glass base material containing at least one selected from the group consisting of nickel, chromium, cobalt, tungsten, iron and manganese, a whisker base material layer disposed on the surface of the base material, and the whisker base material A whisker-forming layer formed of whiskers disposed on the surface of the layer,
The whisker of the whisker forming layer is made of an oxide of tin ,
The whisker base material layer contains the tin ,
The substrate, have a higher melting point than the melting point of tin,
The whisker-forming body , wherein the substrate is a plate-like body or at least one porous body selected from the group consisting of a mesh body, a foamed body, and a punched body. A base material containing at least one selected from the group consisting of nickel, chromium, cobalt, tungsten, iron and manganese, a whisker base material layer disposed on the surface of the base material, and a surface of the whisker base material layer A whisker-forming layer formed of disposed whiskers,
The whisker of the whisker forming layer is made of an oxide of zinc,
The whisker-forming layer contains the zinc;
The substrate has a melting point higher than that of zinc;
The substrate is at least one porous body selected from the group consisting of a plate-like body, a mesh body, a foamed body, and a punched body.
The whisker formation characterized by the above-mentioned. A glass substrate, a whisker base layer disposed on the surface of the base, and a whisker forming layer formed of whiskers disposed on the surface of the whisker base layer,
The whisker of the whisker forming layer is made of an oxide of zinc,
The whisker base material layer includes the zinc;
The substrate has a melting point higher than that of zinc;
The base material is at least one porous body selected from the group consisting of a mesh body, a foamed body, and a punched body.
The whisker formation characterized by the above-mentioned. An electrode for an electrochemical device, wherein the whisker-forming body according to any one of claims 1 to 3 is applied. The electrode for an electrochemical device according to claim 4 , wherein the substrate has conductivity. 6. The substrate according to claim 4 or 5 , wherein the base material does not cause oxidation and reduction reaction at the operating potential of the electrochemical device electrode and does not cause reaction with the electrolyte of the electrochemical device. Electrodes for electrochemical devices. The electrode for an electrochemical device according to any one of claims 4 to 6 , wherein the substrate has translucency. It is a manufacturing method of the whisker formation object as described in any one of Claims 1-3, or the electrode for electrochemical devices as described in any one of Claims 4-7, Comprising: The following process (1) ~ (4)
(1) A step of forming a precursor layer containing tin or zinc which becomes a precursor of the whisker base material layer,
(2) A step that is performed after the step (1) and melts the precursor layer under an inert atmosphere;
(3) A step performed after the step (2) and heating the melted precursor layer in a trace oxygen atmosphere,
(4) A step that is performed after the step (3) and heats the precursor layer at a temperature higher than the step (3) in a trace oxygen atmosphere.
The manufacturing method of the electrode for whisker formation bodies or electrochemical devices characterized by including these. A lithium ion battery comprising the electrode for an electrochemical device according to any one of claims 4 to 6 . A redox capacitor comprising the electrode for an electrochemical device according to any one of claims 4 to 6 . A gas sensor comprising the electrode for an electrochemical device according to any one of claims 4 to 6 . A solar cell comprising the electrode for an electrochemical device according to claim 7 . A module comprising the lithium ion battery according to claim 9 , the redox capacitor according to claim 10 , the gas sensor according to claim 11 , or the solar battery according to claim 12 . A lithium ion battery according to claim 9 , a redox capacitor according to claim 10 , a gas sensor according to claim 11 , a solar battery according to claim 12 , or a module according to claim 13. Moving body.

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