Electrolytic capacitor and method for producing electrolytic capacitor

Patent metadata

Field	Value
Publication number	US-12444546-B2
Application number	US-202118020417-A
Country	US
Kind code	B2
Filing date	Aug 24, 2021
Priority date	Aug 28, 2020
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

An electrolytic capacitor with improved connectivity between a cathode body including a carbon layer and a lead terminal, and a production method thereof are provided. The electrolytic capacitor 1 includes an anode body 2 having a dielectric oxide film 5 on a surface thereof, a cathode body 3 having a cathode foil 31 and a carbon layer 32 formed on the cathode foil 31 , electrolytic solution 6 interposed between the anode body 2 and the cathode body 3 , and a lead terminal 7 connected to each of the anode body 2 and the cathode body 3 by cold pressure welding. A maximum static friction coefficient of a surface of the carbon layer of the cathode body is 0.6 or more.

First claim

The invention claimed is:

1. An electrolytic capacitor comprising:
an anode body having a dielectric layer on a surface thereof;
a cathode body having a cathode foil and a carbon layer formed by pressing on the cathode foil;
an electrolyte interposed between the anode body and the cathode body; and
a lead terminal connected to the anode body and the cathode body by cold pressure welding,
wherein a maximum static friction coefficient of a surface of the carbon layer of the cathode body is 0.6 or more.

2. The electrolytic capacitor according to claim 1 , wherein the carbon layer includes graphite at ratio of 18 wt % or less relative to the total amount of all carbon material in the carbon layer, including none.

3. The electrolytic capacitor according to claim 2 , wherein the carbon layer includes spherical carbon as the carbon material.

4. The electrolytic capacitor according to claim 1 , wherein the carbon layer includes spherical carbon as the carbon material.

5. The electrolytic capacitor according to claim 4 , further comprising:
a cold pressure welded region at a boundary surface between the cathode body and the lead terminal,
wherein the cold pressure welded region has a flat surface and an inclined surface with an inclination angle of 120 degrees or more relative to the flat surface.

6. The electrolytic capacitor according to claim 1 , further comprising:
a cold pressure welded region at a boundary surface between the cathode body and the lead terminal,
wherein the cold pressure welded region has a flat surface and an inclined surface with an inclination angle of 120 degrees or more relative to the flat surface.

7. A production method of an electrolytic capacitor in which an anode body having a dielectric layer on a surface thereof and a cathode body face each other via an electrolyte, the method comprising:
a cathode body production process of forming a carbon layer on a cathode foil and pressing the carbon body having the cathode foil and the carbon layer, and
a cold pressure welding process of connecting the cathode body having the carbon layer formed thereon to a lead terminal by cold pressure welding, wherein a maximum static friction coefficient of a surface of the carbon layer being 0.6 or more.

8. The production method of the electrolytic capacitor according to claim 7 , wherein:
in the cold pressure welding process, the cathode body and the lead terminal are laminated and pressed by a pressing component, and
the pressing component has a flat surface and a side surface with an inclination angle of 120 degrees or more relative to the flat surface.

9. The production method of the electrolytic capacitor according to claim 8 , wherein, in the cold pressure welding process, the carbon layer includes graphite at ratio of 18 wt % or less relative to the total amount of all carbon material in the carbon layer, including none.

10. The production method of the electrolytic capacitor according to claim 8 , wherein, in the cold pressure welding process, the carbon layer includes spherical carbon as the carbon material.

11. The production method of the electrolytic capacitor according to claim 7 , wherein, in the cold pressure welding process, the carbon layer includes graphite at ratio of 18 wt % or less relative to the total amount of all carbon material in the carbon layer, including none.

12. The production method of the electrolytic capacitor according to claim 7 , wherein, in the cold pressure welding process, the carbon layer includes spherical carbon as the carbon material.

Assignees

• Nippon Chemicon

Inventors

• Fukushima Kouta
• Tanabe Keisuke

Classifications

• H01G9/012

  specially adapted for solid capacitors · CPC title

• H01G9/0029

  Processes of manufacture · CPC title

• H01G9/06

  Mounting in containers · CPC title

• H01G9/15

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

• H01G9/055

  Etched foil electrodes · CPC title