CAPACITOR AND METHOD FOR PRODUCING THEREOF

• US 20100165546A1
• Filed: 02/21/2007
• Published: 07/01/2010
• Est. Priority Date: 02/21/2006
• Status: Active Grant

• Current Assignee: Shin-Etsu Polymer Company Limited (Shin-Etsu Chemical Company Limited)
• Original Assignee: Shin-Etsu Polymer Company Limited (Shin-Etsu Chemical Company Limited)
• Inventors: Negishi, Mitsuaki, Yoshida, Kazuyoshi, Fujiki, Hironao, Ning, Tailu
• Granted Patent: US 8,339,770 B2
• Time in Patent Office: Days
• US Class Current: 361/525
• CPC Class Codes: H01G 11/48 Conductive polymers
• CPC Class Codes: H01G 11/52 Separators
• CPC Class Codes: H01G 11/56 Solid electrolytes, e.g. gels; Additives therein
• CPC Class Codes: H01G 9/0036 Formation of the solid electrolyte layer
• CPC Class Codes: H01G 9/028 Organic semiconducting electrolytes, e.g. TCNQ
• CPC Class Codes: H01G 9/042 characterised by the material H01G11/22 takes precedence
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

A capacitor having a high degree of electric strength, a high electrostatic capacity, and a low ESR, which can be readily downsized, is provided. The capacitor according to the present invention includes an anode made of porous valve metal, a dielectric layer formed by oxidizing the surface of the anode, and a solid electrolyte layer formed on the surface of the dielectric layer. The solid electrolyte layer includes a π conjugated conductive polymer, a polyanion, and an ion-conductive compound.

Claims

1. A capacitor comprising:

an anode made of a porous valve metal;

a dielectric layer formed by oxidizing a surface of the anode; and

a solid electrolyte layer formed on a surface of the dielectric layer,

wherein the solid electrolyte layer comprises π

conjugated conductive polymer, a polyanion, and an ion-conductive compound.

2. The capacitor according to claim 1, wherein the ion-conductive compound is a compound having a structure represented by the following Chemical Formula (I):

—

(R—

O)_n—

 

 

(I)

(in the Chemical Formula (I), R represents at least one selected from the group consisting of substituted or unsubstituted alkylenes, substituted or unsubstituted alkenylenes, and substituted or unsubstituted phenylenes, and n represents an integer of 1 to 2,000).

3. The capacitor according to claim 2, wherein the ion-conductive compound is a compound represented by the following Chemical Formula (II):

X—

(R—

O)_n—

Y 

 

(II)

(in the Chemical Formula (II), R represents at least one selected from the group consisting of substituted or unsubstituted alkylenes, substituted or unsubstituted alkenylenes, and substituted or unsubstituted phenylenes, X represents at least one selected from the group consisting of a hydrogen atom, a hydroxyl group, substituted or unsubstituted alkyl groups, substituted or unsubstituted alkoxyl groups, substituted or unsubstituted alkenyl groups, substituted or unsubstituted aryl groups, substituted or unsubstituted glycidyl groups, substituted or unsubstituted (meth)acryloyl groups, and substituted or unsubstituted oxycarbonyl groups, Y represents at least one selected from the group consisting of a hydrogen atom, substituted or unsubstituted alkyl groups, substituted or unsubstituted alkenyl groups, substituted or unsubstituted aryl groups, substituted or unsubstituted glycidyl groups, substituted or unsubstituted (meth)acryloyl groups, and substituted or unsubstituted carbonyl groups, and n represents an integer of 1 to 2,000).

4. The capacitor according to claim 1, wherein the solid electrolyte layer further comprises at least one conductive-enhancer selected from the group consisting of nitrogen-containing aromatic cyclic compounds, compounds having at least two hydroxyl groups, compounds having at least two carboxyl groups, compounds having both at least one hydroxyl group and at least one carboxyl group, compounds having an amido group, compounds having an imido group, lactam compounds, and compounds having a glycidyl group.

9. The capacitor according to claim 1, wherein the solid electrolyte layer further comprises an alkaline compound.

5. A capacitor comprising:

an anode made of a porous valve metal;

a dielectric layer formed by oxidizing a surface of the anode; and

a solid electrolyte layer formed on a surface of the dielectric layer,

wherein the solid electrolyte layer comprises;

a π

conjugated conductive polymer;

a compound having a sulfonic group; and

a water-soluble compound or a water-dispersible compound other than the compound having a sulfonic group.

8. The capacitor according to claim 5, wherein the water-soluble compound is a water-soluble polymer compound.

17. The capacitor according to claim 5, wherein the solid electrolyte layer further comprises an alkaline compound.

6. A capacitor comprising:

an anode made of a porous valve metal;

a dielectric layer formed by oxidizing a surface of the anode by performing a chemical conversion treatment; and

a solid electrolyte layer formed on a surface of the dielectric layer,

wherein a capacitance appearance ratio obtained in accordance with the following Numerical Formula (I);

capacitance appearance ratio(%)=(electrostatic capacity(F)/specific electrostatic capacity (F))×

100 

 

Numerical Formula (I)

is 70 to 100%, and a ratio “

electric strength (V)/formation voltage (V)”

is 0.5 to 1.0.

7. The capacitor according to claim 6, wherein the solid electrolyte layer comprises:

a π

conjugated conductive polymer;

a compound having a sulfonic group; and

a water-soluble compound or a water-dispersible compound other than the compound having a sulfonic group.

16. The capacitor according to claim 6, wherein the water-soluble compound is a water-soluble polymer compound.

18. The capacitor according to claim 6, wherein the solid electrolyte layer further comprises an alkaline compound.

10. A method for producing a capacitor, comprising:

a step in which a conductive polymer solution comprising a π

conjugated conductive polymer, a polyanion, an ion-conductive compound, and a solvent, is applied on a surface of a dielectric layer formed by oxidizing a surface of an anode made of a porous valve metal; and

a step in which the conductive polymer solution applied on the surface of the dielectric layer is dried.

13. The method for producing a capacitor according to claim 10, wherein a pH of the conductive polymer solution at 25°

C. is 3 to 13.

11. A method for producing a capacitor comprising:

a step in which a conductive polymer raw material solution comprising precursor monomers of a π

conjugated conductive polymer, a compound having a sulfonic group, a water-soluble compound or a water-dispersible compound other than the compound having a sulfonic group, and a solvent, is applied on a surface of a dielectric layer formed by oxidizing a surface of an anode made of a porous valve metal; and

a step in which the precursor monomers of the π

conjugated conductive polymer in the conductive polymer raw material solution applied on the surface of the dielectric layer is polymerized.

14. The method for producing a capacitor according to claim 11, wherein a pH of the conductive polymer raw material solution at 25°

C. is 3 to 13.

12. A method for producing a capacitor comprising:

a step in which a conductive polymer solution comprising a π

conjugated conductive polymer, a polymer having a sulfonic group, a water-soluble compound or a water-dispersible compound other than the polymer having a sulfonic group, and a solvent, is applied on a surface of a dielectric layer formed by oxidizing a surface of an anode made of a porous valve metal; and

a step in which the conductive polymer solution applied on the surface of the dielectric layer is dried.

15. The method for producing a capacitor according to claim 12, wherein a pH of the conductive polymer raw material solution at 25°

C. is 3 to 13.