The present invention is directed to an electrolyte for an electrolytic capacitor. The capacitor has an electrolytic anode and an electrochemical cathode. The electrolyte has water, a water soluble organic salt, and a relatively weak organic acid. This electrolyte is chemically compatible to aluminum and tantalum oxide dielectrics and withstands higher voltage while maintaining good conductivity. This makes the electrolyte especially useful for high voltage applications, such as occur in an implantable cardiac defibrillator.
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0. 70. An electrolyte for a capacitor comprising a tantalum anode, the electrolyte consisting of:
a) water;
b) ammonium isobutyrate and isobutyric acid; and
c) 4-nitrophenol (p-nitrophenol),
d) wherein the electrolyte has:
i) a conductivity in the range of 6.9 to 11.5 mS/cm;
ii) a ph in the range of 4.9 to 6.7;
iii) an anode breakdown voltage in the range of 370 to 400 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode; and
iv) does not generate gas at 105° C.
0. 71. A capacitor, which comprises:
a) an anode of tantalum;
b) an electrochemical cathode of ruthenium oxide; and
c) an electrolyte for the anode and the cathode, the electrolyte consisting of:
i) water;
ii) an organic solvent;
iii) ammonium isobutyrate and isobutyric acid; and
iv) 4-nitrophenol (p-nitrophenol),
v) wherein the electrolyte has:
A) a conductivity in the range of 6.9 to 11.5 mS/cm;
B) a ph in the range of 4.9 to 6.7;
C) an anode breakdown voltage in the range of 370 to 400 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode; and
D) does not generate gas at 105° C.
0. 44. An electrolyte for a capacitor comprising a tantalum anode, the electrolyte consisting of:
a) water;
b) an organic acid and an ammonium salt of the organic acid, wherein the ammonium salt and its corresponding acid are selected from the group consisting of: ammonium isobutyrate and isobutyric acid, ammonium butyrate and butyric acid, ammonium propionate and propionic acid, ammonium valerate and valeric acid, ammonium methylbutyrate and methylbutyric acid, and ammonium trimethylacetate and trimethylacetic acid; and
c) a nitroaromatic compound selected from the group consisting of 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 2-nitrobenzonic acid, 3-nitrobenzonic acid, 4-nitrobenzonic acid, 2-nitroacetophenone, 3-nitroacetophenone, 4-nitroacetophenone, 2-nitroanisole, 3-nitroanisole, 4-nitroanisole, 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2-nitrobenzyl alcohol, 3-nitrobenzyl alcohol, 4-nitrobenzyl alcohol, 2-nitrophthalic acid, 3-nitrophthalic acid, 4-nitrophthalic acid, and mixtures thereof,
d) wherein the electrolyte has:
i) a conductivity in the range of 6.9 to 11.5 mS/cm;
ii) a ph in the range of 4.9 to 6.7;
iii) an anode breakdown voltage in the range of 370 to 400 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode; and
iv) does not generate gas at 105° C.
0. 58. An electrolyte for a capacitor comprising a tantalum anode, the electrolyte consisting of:
a) water;
b) an organic solvent selected from the group consisting of glycols, glycol ethers, polyethylene glycols, amides, esters, nitriles, linear carbonates, cyclic carbonates, and mixtures thereof, wherein:
i) the glycol is selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, trimethylene glycol, and mixtures thereof;
ii) the glycol ether is selected from the group consisting of ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol methyl ether, diethylene glycol methyl ether, dipropylene glycol methyl ether, glycol monobutyl ether, and mixtures thereof;
iii) the amide is selected from the group consisting of formamide, dimethyl formamide, diethyl formamide, ethyl formamide, dimethyl acetamide, methyl acetamide, and mixtures thereof;
iv) the ester is selected from the group consisting of γ-butyrolactone, γ-valerolactone, N-methyl-2-pyrrolidone, and mixtures thereof;
v) the nitrile is selected from the group consisting of acetonitrile, propionitrile, and mixtures thereof; and
vi) the linear and cyclic carbonates are selected from the group consisting of dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, dipropyl carbonate, ethyl propyl carbonate, methyl propyl carbonate, propylene carbonate, ethylene carbonate, butylene carbonate, vinylene carbonate, and mixtures thereof; and
c) an organic acid and an ammonium salt of the organic acid, wherein the ammonium salt and its corresponding acid are selected from the group consisting of: ammonium isobutyrate and isobutyric acid, ammonium butyrate and butyric acid, ammonium propionate and propionic acid, ammonium valerate and valeric acid, ammonium methylbutyrate and methylbutyric acid, and ammonium trimethylacetate and trimethylacetic acid; and
d) a nitroaromatic compound selected from the group consisting of 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 2-nitrobenzonic acid, 3-nitrobenzonic acid, 4-nitrobenzonic acid, 2-nitroacetophenone, 3-nitroacetophenone, 4-nitroacetophenone, 2-nitroanisole, 3-nitroanisole, 4-nitroanisole, 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2-nitrobenzyl alcohol, 3-nitrobenzyl alcohol, 4-nitrobenzyl alcohol, 2-nitrophthalic acid, 3-nitrophthalic acid, 4-nitrophthalic acid, and mixtures thereof,
e) wherein the electrolyte has:
i) a conductivity in the range of 6.9 to 11.5 mS/cm;
ii) a ph in the range of 4.9 to 6.7;
iii) an anode breakdown voltage in the range of 370 to 400 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode; and
iv) does not generate gas at 105° C.
0. 59. A capacitor, which comprises:
a) an anode of tantalum;
b) an electrochemical cathode of ruthenium oxide; and
c) an electrolyte for the anode and the cathode, the electrolyte consisting of:
i) water;
ii) an organic solvent selected from the group consisting of glycols, glycol ethers, polyethylene glycols, amides, esters, nitriles, linear carbonates, cyclic carbonates, and mixtures thereof, wherein:
A) the glycol is selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, trimethylene glycol, and mixtures thereof;
B) the glycol ether is selected from the group consisting of ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol methyl ether, diethylene glycol methyl ether, dipropylene glycol methyl ether, glycol monobutyl ether, and mixtures thereof;
C) the amide is selected from the group consisting of formamide, dimethyl formamide, diethyl formamide, ethyl formamide, dimethyl acetamide, methyl acetamide, and mixtures thereof;
D) the ester is selected from the group consisting of γ-butyrolactone, γ-valerolactone, N-methyl-2-pyrrolidone, and mixtures thereof;
E) the nitrile is selected from the group consisting of acetonitrile, propionitrile, and mixtures thereof; and
F) the linear and cyclic carbonates are selected from the group consisting of dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, dipropyl carbonate, ethyl propyl carbonate, methyl propyl carbonate, propylene carbonate, ethylene carbonate, butylene carbonate, vinylene carbonate, and mixtures thereof; and
iii) an organic acid and an ammonium salt of the organic acid, wherein the ammonium salt and its corresponding acid are selected from the group consisting of: ammonium isobutyrate and isobutyric acid, ammonium butyrate and butyric acid, ammonium propionate and propionic acid, ammonium valerate and valeric acid, ammonium methylbutyrate and methylbutyric acid, and ammonium trimethylacetate and trimethylacetic acid;
iv) a nitroaromatic compound selected from the group consisting of 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 2-nitrobenzonic acid, 3-nitrobenzonic acid, 4-nitrobenzonic acid, 2-nitroacetophenone, 3-nitroacetophenone, 4-nitroacetophenone, 2-nitroanisole, 3-nitroanisole, 4-nitroanisole, 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2-nitrobenzyl alcohol, 3-nitrobenzyl alcohol, 4-nitrobenzyl alcohol, 2-nitrophthalic acid, 3-nitrophthalic acid, 4-nitrophthalic acid, and mixtures thereof;
v) an additive selected from the group consisting of phosphoric acid, trimethylphosphate, triethylphosphate, and triisopropylphosphate; and
vi) wherein the electrolyte has:
A) a conductivity in the range of 6.9 to 11.5 mS/cm;
B) a ph in the range of 4.9 to 6.7;
C) an anode breakdown voltage in the range of 370 to 400 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode; and
D) does not generate gas at 105° C.
1. An electrolyte for an electrical energy storage device, the electrolyte consisting essentially of:
a) water;
b) an organic acid; and
c) an ammonium salt of the organic acid.
2. The electrolyte of
3. The electrolyte of
4. The electrolyte of
5. The electrolyte of
6. The electrolyte of
7. The electrolyte of
8. An electrolyte for a capacitor, the electrolyte comprising:
a) water;
b) an organic solvent;
c) an organic acid; and
d) an ammonium salt of the organic acid.
9. The electrolyte of
10. The electrolyte of
11. The electrolyte of
12. The electrolyte of
13. The electrolyte of
14. The electrolyte of
15. The electrolyte of
16. The electrolyte of
17. The electrolyte of
18. A capacitor, which comprises:
a) an anode of a valve metal;
b) an electrochemical cathode selected from the group consisting of a transition metal oxide, a transition metal nitride, a transition metal carbide and a transition metal carbon nitride; and
c) an electrolyte for the anode and the cathode, the electrolyte comprising:
i) water;
ii) an organic solvent;
iii) an organic acid; and
iv) an ammonium salt of the organic acid.
19. The capacitor of
20. The capacitor of
21. The capacitor of
22. The capacitor of
23. The capacitor of
24. The capacitor of
25. The capacitor of
26. The capacitor of
27. The capacitor of
28. The capacitor of
29. The capacitor of
30. The capacitor of
31. The capacitor of
32. The capacitor of
33. A method for providing an electrolyte, consisting essentially of the steps of:
a) providing water;
b) providing an organic acid; and
c) providing an ammonium salt of the organic acid.
34. The method of
35. The method of
36. The method of
37. The method of
38. The method of
39. The method of
40. The method of
41. The method of
42. The method of
43. The method of
0. 45. The electrolyte of claim 44, wherein the water is present in a range of, by weight, about 1% to about 80%.
0. 46. The electrolyte of claim 44, wherein the acid is present in a range of, by weight, about 1% to about 80%.
0. 47. The electrolyte of claim 44, wherein the ammonium salt is present in a range of, by weight, 0.5% to about 50%.
0. 48. The electrolyte of claim 44, wherein the ammonium salt and its corresponding acid are ammonium isobutyrate and isobutyric acid; and
wherein the electrolyte having a ph of 4.9 and an anode breakdown voltage of 395 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode.
0. 49. The electrolyte of claim 48, having a conductivity of 7.1 mS/cm.
0. 50. The electrolyte of claim 44, wherein the ammonium salt and its corresponding acid are ammonium isobutyrate and isobutyric acid; and
wherein the electrolyte having a ph of 5.4 and an anode breakdown voltage of 400 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode.
0. 51. The electrolyte of claim 47, having a conductivity of 6.9 mS/cm.
0. 52. The electrolyte of claim 44, wherein the ammonium salt and its corresponding acid are ammonium isobutyrate and isobutyric acid; and
wherein the electrolyte having a ph of 5.2 and an anode breakdown voltage of 388 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode.
0. 53. The electrolyte of claim 52, having a conductivity of 7.9 mS/cm.
0. 54. The electrolyte of claim 44, wherein the ammonium salt and its corresponding acid are ammonium isobutyrate and isobutyric acid; and
wherein the electrolyte having a ph of 5.7 and an anode breakdown voltage of 380 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode.
0. 55. The electrolyte of claim 54, having a conductivity of 11.5 mS/cm.
0. 56. The electrolyte of claim 45, wherein the ammonium salt and its corresponding acid are ammonium isobutyrate and isobutyric acid; and
wherein the electrolyte having a ph of 6.7 and an anode breakdown voltage of 370 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode.
0. 57. The electrolyte of claim 56, having a conductivity of 10.8 mS/cm.
0. 60. The capacitor of claim 59, wherein the ammonium salt and its corresponding acid for the electrolyte are ammonium isobutyrate and isobutyric acid; and
wherein the electrolyte has a ph of 4.9 and an anode breakdown voltage of 395 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode.
0. 61. The capacitor of claim 60, wherein the electrolyte has a conductivity of 7.1 mS/cm.
0. 62. The capacitor of claim 59, wherein the ammonium salt and its corresponding acid of the electrolyte are ammonium isobutyrate and isobutyric acid; and
wherein the electrolyte has a ph of 5.4 and an anode breakdown voltage of 400 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode.
0. 63. The capacitor of claim 62, wherein the electrolyte has a conductivity of 6.9 mS/cm.
0. 64. The capacitor of claim 59, wherein the ammonium salt and its corresponding acid of the electrolyte are ammonium isobutyrate and isobutyric acid; and
wherein the electrolyte has a ph of 5.2 and an anode breakdown voltage of 388 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode.
0. 65. The capacitor of claim 64, wherein the electrolyte has a conductivity of 7.9 mS/cm.
0. 66. The capacitor of claim 59, wherein the ammonium salt and its corresponding acid of the electrolyte are ammonium isobutyrate and isobutyric acid; and
wherein the electrolyte has a ph of 5.7 and an anode breakdown voltage of 380 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode.
0. 67. The capacitor of claim 66, wherein the electrolyte has a conductivity of 11.5 mS/cm.
0. 68. The capacitor of claim 59, wherein the ammonium salt and its corresponding acid of the electrolyte are ammonium isobutyrate and isobutyric acid; and
wherein the electrolyte has a ph of 6.7 and an anode breakdown voltage of 370 volts when the electrolyte is at room temperature and the breakdown voltage is measured using a tantalum anode.
0. 69. The capacitor of claim 68, wherein the electrolyte has a conductivity of 10.8 mS/cm.
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This application is a reissue of application Ser. No. 10/354,324, filed on Jan. 30, 2003, now U.S. Pat. No. 6,687,117, which claims priority from U.S. provisional application Ser. No. 60/353,895, filed on Jan. 31, 2002.
This invention is directed to an electrolyte for electrolytic capacitors. More particularly, the present invention relates to an electrolyte for high voltage wet tantulum or aluminum capacitors.
The present electrolyte is suitable for an electrolytic capacitor and includes water and an organic solvent having an ammonium salt of a relatively weak organic acid dissolved therein. The organic acid is used to achieve an appropriate pH, conductivity, and breakdown voltage for a particular capacitor application.
An exemplary capacitor includes an anode of a valve metal such as aluminum or tantalum provided with an oxide film on the surface as a dielectric. The oxide film is typically formed by an anodizing process. The anode is kept from contacting a cathode by a separator disposed there between. The separator is impregnated with the present electrolyte. The electrolyte has a relatively high conductivity and breakdown voltage, which ensures that the capacitor exhibits low series resistance while withstanding high voltage. As such, the electrolyte impregnated separator provides the conductivity between the anode and the cathode while supporting the rated voltage. The electrolyte impregnated separator also helps heal the dielectric oxide film on the anode during operation.
These and other aspects and advantages of the present invention will become increasingly more apparent to those skilled in the art by reference to the following description.
An electrolyte according to the present invention preferably contains the following constituents, by weight: about 1% to about 80% de-ionized water and 0% to about 80% of an organic solvent along with about 1% to about 80% isobutyric acid and about 0.5% to about 50% of concentrated ammonium salt (28%). The organic solvent includes, but is not limited to, glycols, glycol ethers, polyethylene glycols, amides, esters, nitriles, linear carbonates, cyclic carbonates, and mixtures thereof.
Suitable glycols include, but are not limited to, ethylene glycol, diethylene glycol, propylene glycol, trimethylene glycol, and mixtures thereof.
Suitable glycol ethers include, but are not limited to, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol methyl ether, diethylene glycol methyl ether, dipropylene glycol methyl ether, glycol monobutyl ether, and mixtures thereof.
Suitable amides include formamide, dimethyl formamide, diethyl formamide, ethyl formamide, dimethyl acetamide, methyl acetamide, and mixtures thereof.
Suitable nitriles include acetonitrile, propionitrile, and mixtures thereof.
Cyclic esters such as γ-butyrolactone, γ-valerolactone and N-methyl-2-pyrrolidone are also useful solvents or co-solvents as are carbonates, both linear and cyclic. Suitable linear and cyclic carbonates include dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, dipropyl carbonate, ethyl propyl carbonate, methyl propyl carbonate, propylene carbonate, ethylene carbonate, butylenes carbonate, vinylene carbonate, and mixtures thereof.
Isobutyric acid can act as both a solvent and a solute. While isobutyric acid is preferred, other relatively weak organic acids of the general formula of cnH2+nO2 (where n=2 to 7) are acceptable. Examples are butyric acid, propionic acid, valeric acid (pentanoic acid), methylbutyric acid, trimethylacetic acid, and mixtures thereof, among others coming under the purview of the above formula.
Ammonium hydroxide is added to react with the acid to form an ammonium salt in situ that provides electrical conductivity. Electrolyte pH and conductivity can be adjusted by the amount of ammonium hydroxide. Ammonium hydroxide can be substituted by an ammonium salt of the corresponding acid constituent. Examples of these salts are ammonium isobutyrate, ammonium butyrate, ammonium propionate, ammonium valerate, ammonium methylbutyrate, ammonium trimethylacetate, and mixtures thereof.
The electrolytes of the present invention are useful for not only conventional electrolytic capacitors, but also those of the electrolytic/electrochemical hybrid type. Capacitor cathodes commonly used in electrolytic capacitors include etched aluminum foil in aluminum electrolytic capacitors, and those commonly used in wet tantalum capacitors such as of silver, sintered valve metal powders, platinum black, and carbon. The cathode of hybrid capacitors include a pseudocapacitive coating of a transition metal oxide, nitride, carbide or carbon nitride, the transition metal being selected from the group consisting of ruthenium, cobalt, manganese, molybdenum, tungsten, tantalum, iron, niobium, iridium, titanium, zirconium, hafnium, rhodium, vanadium, osmium, palladium, platinum, and nickel. The pseudocapacitive coating is deposited on a conductive substrate such as of titanium or tantalum. The electrolytic/electrochemical hybrid capacitor has high energy density and is particularly useful for implantable medical devices such as a cardiac defibrillator.
The anode is of a valve metal consisting of the group vanadium, niobium, tantalum, aluminum, titanium, zirconium and hafnium. The anode can be a foil, etched foil, sintered powder, or any other form of porous substrate of these metals.
A preferred chemistry for a hybrid capacitor comprises a cathode electrode of a porous ruthenium oxide film provided on a titanium substrate coupled with an anode of a sintered tantalum powder pressed into a pellet. The cathode and anode electrodes are segregated from each other by a suitable separator material impregnated with the present working electrolyte. Such a capacitor is described in U.S. Pat. Nos. 5,894,403, 5,920,455 and 5,926,632. These patents are assigned to the assignee of the present invention and incorporated herein by reference.
Electrolytes of present invention may also contain phosphoric acid, an inorganic phosphate or an organic phosphate as an additive to improve anode stability. The examples of organic phosphates are trimethylphosphate, triethylphosphate, triisopropylphosphate, and mxtures thereof.
Finally, electrolytes of present invention may contain a nitroaromatic depolarizer to prevent cathodic gassing during operation. Suitable nitroaromatic compounds include, but are not limited to 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, 2-nitrobenzonic acid, 3-nitrobenzonic acid, 4-nitrobenzonic acid, 2-nitroace tophenone, 3-nitroacetophenone, 4-nitroacetophenone, 2-nitroanisole, 3-nitroanisole, 4-nitroanisole, 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2-nitrobenzyl alcohol, 3-nitrobenzyl alcohol, 4-nitrobenzyl alcohol, 2-nitrophthalic acid, 3-nitrophthalic acid, 4-nitrophthalic acid, and mixtures thereof.
The present electrolyte is useful for capacitors having an operating range of about 175 volts to about 400 volts while maintaining high conductivity. The preferred ruthenium oxide/tantalum hybrid capacitor provides high energy density at voltages of at least about 175 volts, such as is required in an implantable medical device, for example, a cardiac defibrillator. For this reason, it is important that the electrolyte have a high breakdown voltage, high conductivity, suitable pH and good chemical stability over the operating life of the device.
The present electrolyte is chemically compatible over time with the other capacitor components and capacitor materials, even at temperatures of about 105° C. This means that the electrolyte does not generate gas or promote corrosion of the other capacitor components at that temperature.
The following examples describe the manner and process of a capacitor according to the present invention, and they set forth the best mode contemplated by the inventors of carrying out the invention, but they are not to be construed as limiting.
One exemplary electrolyte according to the present invention consists of the constituents listed in Table 1. The anode breakdown voltage measurements set forth in the below tables were conducted using a tantalum anode at room temperature.
TABLE 1
Components
Wt. %
Amount
ethylene glycol
39.17
89.8
(ml)
deionized water
52.88
135.0
(ml)
isobutyric acid
6.0
16.1
(ml)
ammonium hydroxide (28%)
1.5
4.3
(ml)
phosphoric acid (85%)
0.06
0.09
(ml)
p-nitrophenol
0.4
1.0
(g)
It was determined that the above electrolyte had the physical characteristics listed in Table 2.
TABLE 2
pH
4.9
Conductivity
7.1
mS/cm
Anode Breakdown
395
volts
Another exemplary electrolyte according to the present invention consists of the constituents listed in Table 3.
TABLE 3
Components
Wt. %
Amount
ethylene glycol
39.71
359.4
(ml)
deionized water
55.6
560.0
(ml)
isobutyric acid
3.0
31.6
(ml)
ammonium hydroxide (28%)
1.3
14.0
(ml)
phosphoric acid (85%)
0.06
0.36
(ml)
p-nitrophenol
0.4
4.0
(g)
It was determined that the above electrolyte had the physical characteristics listed in Table 4.
TABLE 4
pH
5.4
Conductivity
6.9
mS/cm
Anode Breakdown
400
volts
Another exemplary electrolyte according to the present invention consists of the constituents listed in Table 5.
TABLE 5
Components
Wt. %
Amount
ethylene glycol
18.2
18.0 (ml)
deionized water
9.1
10.0 (ml)
isobutyric acid
64.5
74.7 (ml)
ammonium hydroxide (28%)
8.2
10.0 (ml)
phosphoric acid (85%)
0.09
0.06 (ml)
It was determined that the above electrolyte had the physical characteristics listed in Table 6.
TABLE 6
pH
5.2
Conductivity
7.9
mS/cm
Anode Breakdown
388
volts
Another exemplary electrolyte according to the present invention consists of the constituents listed in Table 7.
TABLE 7
Components
Wt. %
Amount
deionized water
44.88
100.0
(ml)
isobutyric acid
13.5
31.6
(ml)
ammonium hydroxide (28%)
3.2
8.0
(ml)
phosphoric acid (85%)
0.04
0.06
(ml)
ethylene glycol
38.2
91.4
(ml)
monomethyl ether
It was determined that the above electrolyte had the physical characteristics listed in Table 8.
TABLE 8
pH
5.7
Conductivity
11.5
mS/cm
Anode Breakdown
380
volts
Another exemplary electrolyte according to the present invention consists of the constituents listed in Table 9.
TABLE 9
Components
Wt. %
Amount
deionized water
4.69
10.0
(ml)
isobutyric acid
37.5
84.2
(ml)
ammonium hydroxide (28%)
10.6
25.0
(ml)
phosphoric acid (85%)
0.05
0.06
(ml)
ethylene glycol
46.9
107.5
(ml)
monomethyl ether
It was determined that the above electrolyte had the physical characteristics listed in Table 10.
TABLE 10
pH
6.7
Conductivity
10.8
mS/cm
Anode Breakdown
370
volts
It is appreciated that various modifications to the present inventive concepts described herein may be apparent to those of ordinary skill in the art without departing from the spirit and scope of the present invention as defined by the herein appended claims.
| Patent | Priority | Assignee | Title |
| Patent | Priority | Assignee | Title |
| 2089687, | |||
| 2749487, | |||
| 3638077, | |||
| 4476517, | Oct 07 1983 | Sprague Electric Company | Aluminum electrolytic capacitor |
| 4559581, | Jul 18 1983 | U S PHILIPS CORPORATION, A DE CORP | Electrolytic capacitor |
| 4762630, | Mar 28 1986 | Nippon Chemi-Con Corporation | Electrolyte for electrolytic capacitor |
| 4774011, | May 20 1986 | Mitsubishi Petrochemical Co., Ltd. | Electrolyte for aluminum electrolytic capacitor |
| 4885115, | Mar 12 1987 | Nippon Chemi-Con Corporation | Liquid electrolyte for use in electrolytic capacitor |
| 5111365, | Jun 20 1991 | BC COMPONENTS HOLDING B V ; BC COMPONENTS HOLDINGS B V | Electrolytic capacitor provided with a low resistivity electrolyte |
| 5369547, | Mar 22 1993 | Evans Capacitor Company, Incorporated | Capacitor |
| 5496481, | Dec 21 1994 | Boundary Technologies, Inc. | Electrolyte for electrolytic capacitor |
| 5507966, | Mar 22 1995 | Boundary Technologies, Inc. | Electrolyte for an electrolytic capacitor |
| 5629829, | Sep 14 1994 | Kabushiki Kaisha Toshiba | Electrolytic solution for electrolytic capacitor and electrolytic capacitor |
| 5870275, | Aug 25 1995 | Sanyo Chemical Industries, Ltd.; Matsushita Electric Industrial Co., Ltd. | Electrolyte and electronic component using same |
| 6219222, | Aug 28 1998 | GREATBATCH, LTD NEW YORK CORPORATION | Electrolyte for use in a capacitor |
| 6261434, | Oct 19 1999 | Kemet Electronics Corporation | Differential anodization process for electrolytic capacitor anode bodies |
| 6285543, | Dec 01 1998 | RUBYCON CORPORATION | Electrolytic solution for use in electrolytic capacitor and electrolytic capacitor |
| 6368485, | Nov 18 1997 | Mitsubishi Chemical Corporation | Forming electrolyte for forming metal oxide coating film |
| 6687117, | Jan 31 2002 | Greatbatch Ltd | Electrolytes for capacitors |
| 20030142464, | |||
| EP989572, | |||
| WO33338, |
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