Method for improving the electrical parameters in capacitors containing PEDOT/PSS as a solid electrolyte by polyglycerol

Patent metadata

Field	Value
Publication number	US-9502183-B2
Application number	US-201214020311-A
Country	US
Kind code	B2
Filing date	Feb 24, 2012
Priority date	Mar 6, 2011
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

Capacitors comprising a dielectric at least partly covering the surface of an electrode material and forming an anode body are described. The anode body may be at least partly coated with a solid electrolyte comprising a conductive polymer. The capacitor comprises at least one polyglycerol, where the ratio of the amount of polyglycerol (M pg ) to the amount of conductive polymer (M polymer ) in the capacitor is M pg /M polymer >0.15, and the polyglycerol contains more than 50 wt. % of a mixture of tri- and tetraglycerol, based on the total weight of the polyglycerol. Processes for the production of a capacitor, an electronic circuit and use of a capacitor in a dispersion are also described.

First claim

The invention claimed is:

1. A capacitor comprising an electrode body of an electrode material, wherein a dielectric at least partly covers a surface of the electrode material and forms an anode body,
wherein the anode body is at least partly coated with a solid electrolyte which comprises a conductive polymer,
wherein the capacitor comprises at least one polyglycerol, and wherein for the ratio of the amount by weight of polyglycerol (M pg ) in the capacitor and the amount by weight of conductive polymer (M polymer ) in the capacitor:
M pg /M polymer >0.15,

wherein the polyglycerol contains more than 50 wt. % of a mixture of a tri- and tetraglycerol, based on the total weight of the polyglycerol.

2. The capacitor according to claim 1 , wherein for the M pg /M polymer ratio:
M pg /M polymer >0.2.

3. The capacitor according to claim 1 , wherein for the M pg /M polymer ratio:
M pg /M polymer is in a range of from 0.2 to 80.

4. The capacitor according to claim 1 , wherein for the M pg /M polymer ratio:
M pg /M polymer is in a range of from 2.5 to 30.

5. The capacitor according to claim 1 , wherein the capacitor is an aluminium capacitor.

6. The capacitor according to claim 1 , wherein the conductive polymer comprises a polythiophene.

7. The capacitor according to claim 6 , wherein the polythiophene comprises a poly(3,4-ethylenedioxythiophene).

8. The capacitor according to claim 6 , wherein the conductive polymer comprises a complex of poly(3,4-ethylenedioxythiophene) and polystyrenesulphonic acid.

9. The capacitor according to claim 1 , wherein the conductive polymer comprises a polythiophene with recurring units of the general formula (I) or (II)

wherein
A represents an optionally substituted C 1 -C 5 -alkylene radical,
R represents a linear or branched, optionally substituted C 1 -C 18 -alkyl radical, an optionally substituted C 5 -C 12 -cycloalkyl radical, an optionally substituted C 6 -C 14 -aryl radical, an optionally substituted C 7 -C 18 -aralkyl radical, an optionally substituted C 1 -C 4 -hydroxyalkyl radical or a hydroxyl radical,
x represents an integer from 0 to 8 and
in the case where several radicals R are bonded to A, these can be identical or different.

10. The capacitor according to claim 1 , wherein the conductive polymer comprises a polyanion.

11. The capacitor according to claim 10 , wherein the polyanion comprises a polystyrenesulphonic acid.

12. A process for the production of a capacitor, comprising the process steps:
a1) providing an electrode body of an electrode material, wherein a dielectric covers one surface of this electrode material at least partly to form an anode body;
b1) introducing a dispersion comprising
a conductive polymer,
at least one polyglycerol, and
a dispersing agent

into at least a part of the anode body;
c1) at least partially removing the dispersing agent to obtain a capacitor body;
or
a2) providing an electrode body of an electrode material, wherein a dielectric covers one surface of the electrode material at least partly to form an anode body;
b2) introducing a dispersion comprising
a conductive polymer, and
a dispersing agent

into at least a part of the anode body;
c2) at least partially removing the dispersing agent to obtain a capacitor body;
d2) bringing into contact at least one polyglycerol, as an impregnating agent, with the capacitor body;
or
a3) providing an electrode body of an electrode material, wherein a dielectric covers one surface of the electrode material at least partly to form an anode body;
b3) introducing a dispersion comprising
a conductive polymer,
at least one polyglycerol, and
a dispersing agent

into at least a part of the anode body;
c3) at least partially removing the dispersing agent to obtain a capacitor body;
d3) bringing into contact at least one polyglycerol, as an impregnating agent, with the capacitor body;
wherein the polyglycerol is employed in an amount such that for the ratio of the amount by weight of polyglycerol (M pg ) in the capacitor and the amount by weight of conductive polymer (M polymer ) in the capacitor:
M pg /M polymer >0.15,

wherein the polyglycerol contains more than 50 wt. % of a mixture of a tri- and tetraglycerol, based on the total weight of the polyglycerol.

13. The process according to claim 12 , wherein the polyglycerol is employed in an amount such that for the M pg /M polymer ratio:
M pg /M polymer >0.2.

14. The process according to claim 12 , wherein the polyglycerol is employed in an amount such that for the M pg /M polymer ratio:
M pg /M polymer is in a range of from 0.2 to 80.

15. The process according to claim 12 , wherein the conductive polymer comprises a polythiophene.

16. The process according to claim 15 , wherein the conductive polymer comprises a complex of poly(3,4-ethylenedioxythiophene) and polystyrenesulphonic acid.

17. The process according to claim 12 , wherein the conductive polymer comprises a polythiophene with recurring units of the general formula (I) or (II)

wherein
A represents an optionally substituted C 1 -C 5 -alkylene radical,
R represents a linear or branched, optionally substituted C 1 -C 18 -alkyl radical, an optionally substituted C 5 -C 12 -cycloalkyl radical, an optionally substituted C 6 -C 14 -aryl radical, an optionally substituted C 7 -C 18 -aralkyl radical, an optionally substituted C 1 -C 4 -hydroxyalkyl radical or a hydroxyl radical,
x represents an integer from 0 to 8 and
in the case where several radicals R are bonded to A, these can be identical or different.

18. The process according to claim 12 , wherein the conductive polymer comprises a polyanion.

19. The process according to claim 12 , wherein the impregnating agent is employed in process step d2) and d3) is in the form of a solution comprising a solvent and the impregnating agent and in a further process step e2) or e3) the solvent is at least partly removed from the electrode body.

20. A dispersion comprising a conductive polymer and at least one polyglycerol, wherein the polyglycerol contains more than 50 wt. % of a mixture of a tri- and tetraglycerol, in each case based on the total weight of the polyglycerol.

21. The dispersion according to claim 20 , wherein the dispersion comprises 0.4 to 40 wt.-% of the polyglycerol, based on the total weight of the dispersion.

22. The dispersion according to claim 20 , wherein the dispersion comprises 4 to 13 wt.-% of the polyglycerol, based on the total weight of the dispersion.

Assignees

• Saulter Armin
• Asteman Katrin
• Guntermann Udo
• Merker Udo
• Heraeus Precious Metals Gmbh

Inventors

• Saulter Armin
• Asteman Katrin
• Guntermann Udo
• Merker Udo

Classifications

• H01G9/025

  Solid electrolytes (H01G11/54 takes precedence) · CPC title

• H01G9/028 Primary

  Organic semiconducting electrolytes, e.g. TCNQ · CPC title

• H01G9/0036

  Formation of the solid electrolyte layer · CPC title

• H01G11/56

  Solid electrolytes, e.g. gels; Additives therein · CPC title

• H01G9/15

  Solid electrolytic capacitors (H01G11/00 takes precedence) · CPC title