Claims
- 1. A conductive electrolyte for high voltage electrolytic capacitors, comprising:ethylene glycol; a polar organic solvent; boric acid; a dicarboxylic acid; and an amine.
- 2. An electrolyte according to claim 1, wherein said polar organic solvent is an alcohol, an alkoxyalcohol or a glycol.
- 3. An electrolyte according to claim 1, wherein said polar organic solvent is 2-methoxyethanol.
- 4. An electrolyte according to claim 1, wherein said polar organic solvent is 2-ethoxyethanol.
- 5. An electrolyte according to claim 1, wherein said polar organic solvent is 2-butoxyethanol.
- 6. An electrolyte according to claim 1, wherein said polar organic solvent is hexyl alcohol.
- 7. An electrolyte according to claim 1, wherein said polar organic solvent is di(ethylene glycol).
- 8. An electrolyte according to claim 1, wherein said dicarboxylic acid is an aliphatic dicarboxylic acid of carbon chain length from eight to thirteen (C8 to C13).
- 9. An electrolyte according to claim 8, wherein said aliphatic dicarboxylic acid is selected from the group consisting of suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid and brassylic acid.
- 10. An electrolyte according to claim 1, wherein said dicarboxylic acid is a dicarboxylic acid where the acid functional groups are separated by 34 carbons (dimer acid).
- 11. An electrolyte according to claim 1, wherein said amine is selected from the group consisting of ammonia, dimethylamine, trimethylamine, diethylamine, triethylamine, ethanolamine, diethanolamine, triethanolamine and diisopropylethylamine.
- 12. An electrolyte according to claim 1, further comprising hypophosphorous acid.
- 13. An electrolyte according to claim 1, further comprising a colloidal suspension of silica in ethylene glycol.
- 14. An electrolyte according to claim 1, further comprising a cathode depolarizer.
- 15. An electrolyte according to claim 12, wherein said cathode depolarizer is a nitro-substitute aromatic compound.
- 16. An electrolyte according to claim 13, wherein said nitro-substituted aromatic compound is selected from the group consisting of: nitrobenzene, nitrotoluene, nitrophenol, nitroacetophenone, nitrobenzyl alcohol and nitroanisole.
- 17. An electrolyte according to claim 1, wherein said electrolytic capacitor has a working voltage of greater than 400 V.
- 18. A conductive electrolyte for high voltage electrolytic capacitors, comprising ethylene glycol, 2-ethoxyethanol, boric acid, azelaic acid, 3-nitroacetophenone, a colloidal silica in ethylene glycol, hypophosphorous acid, ammonium hydroxide and water.
- 19. An electrolyte according to claim 18, comprising about 40% to about 80% by weight ethylene glycol, no more than about 40% by weight 2-ethoxyethanol, no more than about 2% by weight boric acid, about 3% to about 6% by weight azelaic acid, no more than about 2% by weight 3-nitroacetophenone, no more than about 10% by weight of a colloidal silica in ethylene glycol, no more than about 2% by weight hypophosphorous acid, no more than about 5% by weight ammonium hydroxide and about 1% to about 10% by weight water.
- 20. An electrolyte according to claim 18, comprising 54.8% by weight ethylene glycol, 23.4% by weight 2-ethoxyethanol, 0.9% by weight boric acid, 5.3% by weight azelaic acid, 0.9% by weight 3-nitroacetophenone, 9.7% by weight colloidal silica (20%) in ethylene glycol, 0.1% by weight hypophosphorous acid (50% in water), 1.4% by weight ammonium hydroxide (30% in water) and 3.5% by weight water.
- 21. An electrolytic capacitor impregnated with the conductive electrolyte of claim 1.
- 22. An electrolytic capacitor impregnated with the conductive electrolyte of claim 18.
- 23. An implantable cardioverter defibrillator (ICD) comprising an electrolytic capacitor impregnated with the conductive electrolyte of claim 1.
- 24. An implantable cardioverter defibrillator (ICD) comprising an electrolytic capacitor impregnated with the conductive electrolyte of claim 18.
- 25. A method of making a conductive electrolyte for high voltage electrolytic capacitors, comprising:(1) mixing an ethylene glycol solvent, a polar organic solvent, boric acid, and a dicarboxylic acid to form a first solution; and (2) adding an amine to said solution to neutralize the pH of said solution.
- 26. A method according to claim 25 wherein step (1) is performed in the following order:(a) mixing an ethylene glycol solvent with boric acid and a dicarboxylic acid; and (b) adding a polar organic solvent.
- 27. A method according to claim 25 further comprising the step of:(3) adding a hypophosphorous acid.
- 28. A method according to claim 25 further comprising the step of:(3) adding a colloidal suspension of silica in ethylene glycol.
- 29. A method according to claim 25 further comprising the step of:(3) adding a cathode depolarizer.
- 30. A method according to claim 25, wherein step (2) achieves a final pH of said solution of about 6.0 to about 10.0.
- 31. A method according to claim 25, wherein step (2) achieves a final pH of said solution of about 6.5 to about 7.5.
Parent Case Info
This application is related to copending application Ser. No. 10/154,569, filed on May 23, 2002, now U.S. Pat. No. 6,587,329.
US Referenced Citations (9)