ELECTROLYTIC CAPACITOR EMPLOYING PASTE ELECTRODES

• US 3,634,736 A
• Filed: 09/14/1970
• Issued: 01/11/1972
• Est. Priority Date: 09/14/1970
• Status: Expired due to Term

• Current Assignee: Richardson-Vicks, Inc. (The Procter & Gamble Company)
• Original Assignee: Donald L. Boos, Joseph E. Metcalfe
• Inventors: Boos, Donald L., Metcalfe, Joseph E.
• Primary Examiner(s): Kallam, James D.
• Application Number:
  US05/071,852
• Time in Patent Office: 484 Days
• Field of Search: 317/230,231,233,237
• US Class Current: 361/502
• CPC Class Codes: H01G 11/04 Hybrid capacitors
• CPC Class Codes: H01G 11/24 characterised by structural features of the materials making up or comprised in the electrodes, e.g. form, surface area or porosity; characterised by the structural features of powders or particles used therefor
• CPC Class Codes: H01G 11/32 Carbon-based
• CPC Class Codes: H01G 11/58 Liquid electrolytes
• CPC Class Codes: H01G 11/78 Cases; Housings; Encapsulations; Mountings
• CPC Class Codes: H01G 11/84 Processes for the manufacture of hybrid or EDL capacitors, or components thereof
• CPC Class Codes: Y02E 60/13 Energy storage using capacitors

Abstract

A high-capacitance, low-voltage electrolytic capacitor consists essentially of a pair of paste electrodes and a separator saturated with electrolyte which functions as an electronic insulator and an ionic conductor. One of said electrodes is composed of active carbon and the opposing electrode is composed of refractory hard boron carbide or a refractory hard metal carbide or boride wherein the metal may be tungsten, titanium, tantalum, niobium or zirconium, said electrodes being prepared by mixing finely divided particulate material of the above compositions with electrolyte to form a viscous paste and compressing the paste to form the electrodes.

Claims

2. Capacitor of claim 1 wherein said carbon paste electrode comprises activated carbon material having a surface area in the range of 100-2,000 meters2/g., admixed with said electrolyte.

3. Capacitor of claim 1 wherein said separator is a porous separator saturated with an electrolyte.

4. Capacitor of claim 3 wherein said saturated porous separator includes a wetting agent facilitating saturation of said separator with said electrolyte.

5. Capacitor of claim 1 including an electrically conducting member on the surface of each of said electrodes facing way from the separator-contact surface, said member functioning as a current collector and as an impervious barrier to the passage of said electrolyte.

6. Capacitor of claim 5 including an annular insulating flexible means for confining the periphery of said electrodes held captive by said member.

7. The capacitor of claim 6 wherein the capacitor assembly of the component parts is compressed under a pressure of at least 240 p.s.i. to render said capacitor a compact unit.

8. An electrolytic capacitor comprising a plurality of cells connected in series, each cell consisting essentially of a pair of paste electrodes, an ionically conducting separator means interposed between and electronically separating said electrodes, and a conducting current collector member forming an impervious barrier to the passage of said electrolyte disposed between said cells, one of said electrodes containing activated carbon material having a surface area in the range of 100-2,000 meters2/g. and the opposing electrode consisting of a refractory hard carbide or boride selected from the group consisting of boron carbide, tantalum carbide, zirconium carbide, tungsten carbide, titanium carbide, niobium carbide, tantalum boride, zirconium boride, tungsten boride, titanium boride, and niobium boride, said electrode materials being mixed with an electrolyte forming a viscous paste.

9. Capacitor of claim 8 wherein said separator is saturated with said electrolyte and said activated carbon material has a surface area in the range of 500-1,500 meters2/g.

10. Capacitor of claim 9 including an insulating flexible annular means held captive by said members for confining periphery of said electrodes.