Solid electrolytic capacitor

Patent metadata

Field	Value
Publication number	US-2018211787-A1
Application number	US-201815861523-A
Country	US
Kind code	A1
Filing date	Jan 3, 2018
Priority date	Jan 20, 2017
Publication date	Jul 26, 2018
Grant date	—

Abstract

In a capacitor element of a solid electrolytic capacitor, a solid electrolytic layer has an edge portion near a root of a lead-out portion. An anode terminal is connected to the lead out portion at a position away from the root of the lead out portion. An ion trapping member includes a first resin and an ion trapping agent dispersed in the first resin. The ion trapping member covers the whole periphery of at least a part of the lead out portion directly or via the dielectric layer between the edge portion of the solid electrolytic layer and the anode terminal. An external insulation member includes a second resin having a high affinity for the first resin. The external insulation member envelops the capacitor element and covers at least a part of the ion trapping member, a part of the anode terminal and a part of a cathode terminal.

First claim

What is claimed is:

1 . A solid electrolytic capacitor comprising a capacitor element, an anode terminal, a cathode terminal, an ion trapping member and an external insulation member, wherein:
the capacitor element comprises an anode body, an anode lead wire extending outward from inside the anode body, a dielectric layer and a cathode layer including a solid electrolytic layer; the dielectric layer is positioned between the anode body and the solid electrolytic layer; the anode lead wire has a lead out portion protruding outward from the anode body; the lead out portion is covered with the dielectric layer at least in part; the solid electrolytic layer has an edge portion near a root of the lead out portion; the anode terminal is connected to the lead out portion at a position away from the root; the cathode terminal is connected to the cathode layer; the ion trapping member comprises a first resin and an ion trapping agent dispersed in the first resin; the ion trapping member covers a whole periphery of at least a part of the lead out portion directly or via the dielectric layer between the edge portion of the solid electrolytic layer and the anode terminal; the external insulation member comprises a second resin which has a high affinity for the first resin; and the external insulating member envelops the capacitor element and covers at least a part of the ion trapping member, a part of the anode terminal and a part of the cathode terminal.

2 . The solid electrolytic capacitor as recited in claim 1 , wherein the ion trapping member is provided to shut a metal ion passing path which is possible to be formed along a surface of the capacitor element between the edge portion of the solid electrolytic layer and anode terminal.

3 . The solid electrolytic capacitor as recited in claim 1 , wherein the ion trapping member envelops a part of the lead out portion that is closer to an end of the lead out portion than the edge portion of the solid electrolytic layer.

4 . The solid electrolytic capacitor as recited in claim 1 , wherein the ion trapping member has the ion trapping agent of 1 weight % or more and 20 weight % or less.

5 . The solid electrolytic capacitor as recited in claim 1 , wherein the ion trapping agent comprises a negative ion trapping agent.

6 . The solid electrolytic capacitor as recited in claim 1 , wherein the ion trapping agent comprises a positive ion trapping agent.

7 . The solid electrolytic capacitor as recited in claim 1 , further comprising a connection member which connects the lead out portion with the anode terminal electrically, wherein the ion trapping member covers the connection member.

Assignees

• Tokin Corp

Inventors

• Saito Kazuaki
• Yoshida Yuji
• Araki Kenji

Classifications

• H01G9/0032

  formation of the dielectric layer · CPC title

• H01G9/0036

  Formation of the solid electrolyte layer · CPC title

• H01G9/0003 Primary

  Protection against electric or thermal overload; cooling arrangements; means for avoiding the formation of cathode films (H01G9/12 takes precedence) · CPC title

• H01G9/012

  specially adapted for solid capacitors · CPC title

• H01G9/07

  Dielectric layers · CPC title