Stack capacitor having high volumetric efficiency
An improved capacitor and method of making an improved capacitor is set forth. The capacitor has planer anodes with each anode comprising a fusion end and a separated end and the anodes are in parallel arrangement with each anode in direct electrical contact with all adjacent anodes at the fusion end. A dielectric is on the said separated end of each anode wherein the dielectric covers at least an active area of the capacitor. Spacers separate adjacent dielectrics and the interstitial space between the adjacent dielectrics and spacers has a conductive material in therein.
1. A method of making a capacitor comprising:
providing planer anodes wherein each anode of said anodes comprises a fusing end and a separated end wherein each said anode comprises a dielectric covering at least a portion of said separated end;
applying a matrix to said dielectric of at least a portion of said anodes wherein said matrix comprises a binder and a spacer;
forming a layered stack of said anodes wherein at least one matrix is between adjacent dielectrics;
fusing said anodes at said fusing end;
partially removing said binder thereby forming interstitial spaces between said adjacent dielectrics with said adjacent dielectrics separated by said spacers;
inserting a conductive material in said interstitial spaces and over an exterior of said layered stack;
electrically attaching an anode lead to said fused anodes; and
electrically attaching a cathode lead to said conductive material.
2. The method of forming a capacitor of claim 1 further comprising:
forming a conductive carbon layer on said conductive coating over said exterior of said layered stack prior to said electrically attaching said cathode lead.
3. The method of forming a capacitor of claim 2 further comprising:
forming a metal layer on said conductive carbon layer prior to said electrically attaching said cathode lead.
4. The method of forming a capacitor of claim 1 wherein said removing of said binder includes heating said binder.
5. The method of forming a capacitor of claim 1 wherein said anode comprises a material selected from the group consisting of Ta, Nb, Al, NbO, Ti, Zr and alloys thereof.
6. The method of forming a capacitor of claim 1 wherein said conductive material is selected from intrinsically conductive polymers, charge transfer conducting compounds or conductive oxides.
7. The method of forming a capacitor of claim 6 wherein said conductive material comprises a polythiophene.
8. The method of forming a capacitor of claim 7 wherein said conductive material comprises poly 3,4-ethylene dioxythiophene.
9. The method of forming a capacitor of claim 6 wherein said conductive material comprises manganese dioxide.
10. The method of forming a capacitor of claim 6 wherein said inserting said conductive polymer comprises introduction of an oxidizer and a monomer into said interstitial spaces.
11. The method of forming a capacitor of claim 10 wherein said monomer is introduced into said interstitial space prior to introduction of said oxidizer.
12. The method of forming a capacitor of claim 6 wherein said inserting said conductive polymer comprises introduction of a slurry comprising said polymer to said interstitial space.
13. The method of forming a capacitor of claim 1 wherein said spacer comprises carbonized fibers.
14. The method of forming a capacitor of claim 13 wherein said fibrous materials have an average cross-sectional size at least 1 to no more than 100 μm along the diameter direction.
15. The method of forming a capacitor of claim 13 wherein said carbonized fibers have a length of at least 1 to no more than 150 μm.
16. The method of forming a capacitor of claim 1 wherein adjacent dielectrics are separated by at least 1 to no more than 100 μm.
17. The method of forming a capacitor of claim 1 further comprising carbonizing a polymer to form said spacer.
18. The method of forming a capacitor of claim 17 wherein said polymer comprises hydroxy or carboxylic groups.
19. The method of forming a capacitor of claim 17 wherein said polymer comprises at least one material selected from cellulose and pentosan.
20. The method of forming a capacitor of claim 19 wherein said polymer comprises 25-85 wt % cellulose.
21. The method of forming a capacitor of claim 19 wherein said polymer comprises 15-75 wt % pentosan.
22. The method of forming a capacitor of claim 1 wherein said binder comprises a material selected from the group consisting of fibrin, cellulose, glucose, protein and gelatin.
23. The method of forming a capacitor of claim 22 wherein said binder is starch.
24. The method of forming a capacitor of claim 1 wherein said inserting said conductive material comprises applying vacuum to said layered stack.
25. The method of forming a capacitor of claim 1 wherein said fusing said anodes comprises welding.
26. The method of forming a capacitor of claim 1 comprising at least 2 planer anodes to no more than 80 planer anodes.
27. The method of forming a capacitor of claim 1 wherein said forming said stacked layer comprises alternating anodes comprising said matrix coating with anodes not comprising said matrix coating.