Electrolytic capacitor and method for producing same

Patent metadata

Field	Value
Publication number	US-2023078283-A1
Application number	US-202117795802-A
Country	US
Kind code	A1
Filing date	Jan 29, 2021
Priority date	Jan 31, 2020
Publication date	Mar 16, 2023
Grant date	—

Abstract

Disclosed is an electrolytic capacitor including a capacitor element. The capacitor element includes an anode body having a dielectric layer formed at a surface of the anode body, and an electrolyte layer disposed adjacent to the dielectric layer. The electrolyte layer contains a conductive polymer doped with a dopant, conductive particles, and a non-aqueous solvent.

First claim

1 . An electrolytic capacitor, comprising a capacitor element, wherein
the capacitor element includes an anode body having a dielectric layer formed at a surface of the anode body, and an electrolyte layer disposed adjacent to the dielectric layer, and the electrolyte layer contains a conductive polymer doped with a dopant, conductive particles, and a non-aqueous solvent.

2 . The electrolytic capacitor according to claim 1 , wherein
the dopant is a polymer dopant containing an acidic group, and the electrolyte layer contains an electrolyte solution including the non-aqueous solvent and a base component dissolved in the non-aqueous solvent.

3 . The electrolytic capacitor according to claim 2 , wherein a content of the base component in the electrolyte solution is 0.1 mass % or more and 20 mass % or less.

4 . The electrolytic capacitor according to claim 1 , wherein a total mass of the conductive polymer and the dopant contained in the electrolyte layer is larger than a mass of the conductive particles contained in the electrolyte layer.

5 . The electrolytic capacitor according to claim 1 , wherein the conductive particles are particles of a conductive carbon material.

6 . The electrolytic capacitor according to claim 1 , wherein the conductive particles include at least one kind of particles selected from the group consisting of carbon black particles, carbon nanotube particles, graphite particles, and graphene particles.

7 . The electrolytic capacitor according to claim 1 , wherein
the anode body has a porous portion at the surface, an average particle diameter of the conductive particles is larger than an average pore diameter of the porous portion, the conductive polymer is in a particle form, and an average particle diameter of the conductive polymer is smaller than the average pore diameter of the porous portion.

8 . The electrolytic capacitor according to claim 1 , wherein
the electrolyte layer includes a polymer layer constituted of the conductive polymer, the polymer layer includes a first polymer layer formed on the dielectric layer, and a second polymer layer formed on the first polymer layer, and a content (mass %) of the conductive particles in the second polymer layer is larger than a content (mass %) of the conductive particles in the first polymer layer.

9 . The electrolytic capacitor according to claim 1 , wherein
the dopant is polystyrene sulfonic acid, and the conductive polymer is poly(3,4-ethylenedioxythiophene).

10 . A method for producing an electrolytic capacitor, the method comprising:
a step (i) of preparing a capacitor element precursor including an anode body having a dielectric layer formed at a surface of the anode body, a step (ii) of forming a polymer layer containing a conductive polymer doped with a dopant, and conductive particles, so as to be adjacent to the dielectric layer, by an impregnation treatment, and a step (iii) of impregnating the polymer layer with a non-aqueous solvent.

11 . The method according to claim 10 , wherein
the dopant is a polymer dopant containing an acidic group, and the step (iii) is a step of impregnating the polymer layer with an electrolyte solution including the non-aqueous solvent and a base component dissolved in the non-aqueous solvent.

12 . The method according to claim 10 , wherein the impregnation treatment in the step (ii) is an impregnation treatment (x) of impregnating the capacitor element precursor with a dispersion including the conductive polymer doped with the dopant and the conductive particles.

13 . The method according to claim 10 , wherein
the impregnation treatment in the step (ii) includes an impregnation treatment (y) of impregnating the capacitor element precursor with a first dispersion including the conductive polymer doped with the dopant, and an impregnation treatment (z) of impregnating the capacitor element precursor with a second dispersion including the conductive particles.

14 . The method according to claim 10 , wherein
the dopant is polystyrene sulfonic acid, and the conductive polymer is poly(3,4-ethylenedioxythiophene).

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Arima Hiroyuki
• Kobayashi Takehiro

Classifications

• H01G9/145

  Liquid electrolytic capacitors (H01G11/00 takes precedence) · CPC title

• H01G9/15

  Solid electrolytic capacitors (H01G11/00 takes precedence) · CPC title

• H01G9/0036

  Formation of the solid electrolyte layer · CPC title

• H01G9/035

  Liquid electrolytes, e.g. impregnating materials (H01G11/54 takes precedence) · CPC title

• H01G9/028 Primary

  Organic semiconducting electrolytes, e.g. TCNQ · CPC title