Stacked solid electrolytic capacitor

Abstract

A stacked solid electrolytic capacitor has a substrate, a capacitor element, and a metal cap. The substrate has electrical conductivity. The capacitor element is provided on the substrate. The metal cap is coupled to the substrate, covers the capacitor element and is electrically conducted to the substrate. A cathode of the capacitor element is electrically conducted to the substrate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention will be described in detail with reference to the following drawings, wherein:

FIG. 1A through FIG. 1C illustrate a stacked solid electrolytic capacitor in accordance with a first embodiment of the present invention;

FIG. 2 illustrates a cross sectional view of a capacitor element taken along a line A-A of FIG. 1A;

FIG. 3A through FIG. 3C illustrate a solid electrolytic capacitor in accordance with a second embodiment of the present invention;

FIG. 4A through FIG. 4C illustrate a shape of an anode foil and a cathode foil; and

FIG. 5 illustrates a cross sectional view taken along a line B-B of FIG. 4A.

Claims

1. A stacked solid electrolytic capacitor comprising: a substrate having electrical conductivity;a capacitor element provided on the substrate; anda metal cap that is coupled to the substrate, covers the capacitor element and is electrically conducted to the substrate,wherein a cathode of the capacitor element is electrically conducted to the substrate.

2. The stacked solid electrolytic capacitor as claimed in claim 1, wherein the metal cap is welded to the substrate.

3. The stacked solid electrolytic capacitor as claimed in claim 1, wherein:the substrate is composed of a metal or a ceramics having a metal formed on a surface thereof, has a cathode terminal and has at least a through hole; andthe stacked solid electrolytic capacitor further comprises an anode terminal extracted outside from an anode of the capacitor element through the through hole.

4. The stacked solid electrolytic capacitor as claimed in claim 3, further comprising an insulating material provided between the substrate and the anode terminal in the through hole.

5. The stacked solid electrolytic capacitor as claimed in claim 4, wherein the insulating material is composed of a glass or a rubber.

6. The stacked solid electrolytic capacitor as claimed in claim 3, further comprising an insulating layer provided between the anode terminal and the cathode terminal at a bottom face of the substrate.

7. The stacked solid electrolytic capacitor as claimed in claim 1, further comprising an insulating layer formed on an inner face of the metal cap.

8. The stacked solid electrolytic capacitor as claimed in claim 1, wherein:the capacitor element has a unit element in which an electrolyte layer having a separator, a carbon paste and an extractor cathode layer are formed on a surface of an anode foil in order,the anode foil being composed of a valve metal; andthe substrate is electrically conducted to the extracting cathode layer.

9. The stacked solid electrolytic capacitor as claimed in claim 8, wherein:the capacitor element has a structure in which a plurality of the unit elements are stacked; andthe extractor cathode layer of the bottom one of the capacitor elements is electrically conducted to the substrate.

10. The stacked solid electrolytic capacitor as claimed in claim 1, wherein:the capacitor element having a structure in which an electrolyte layer having a separator and a cathode foil are formed on both faces of an anode foil composed of a valve metal in order,the cathode foil holding carbide grain on a face thereof on the side of the solid electrolyte layer; andthe substrate is electrically conducted to the cathode foil.

11. The stacked solid electrolytic capacitor as claimed in claim 10, wherein the cathode foil of each unit element is electrically conducted to each other.

12. The stacked solid electrolytic capacitor as claimed in claim 10, wherein:the capacitor element has a structure in which a plurality of the unit elements are stacked; andthe cathode foil of each unit element is electrically conducted to each other.