# US RE47,435 E1 · Electrolytes for use in a capacitor

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- Number: US RE47,435 E1
- Document ID: USRE47435E1
- Status: Granted
- Kind: E1
- Application number: 14/645,539
- Filed: 2015-03-12
- Granted: 2019-06-11
- Earliest claimed: 1998-08-28
- Assignees: Greatbatch Ltd.
- Applicants: Greatbatch Ltd.
- Inventors: Ashish Shah; Christina Scheuer; Lauren (Miller) Matyjas; Barry C. Muffoletto
- Web page: https://patentgrep.com/patent/USRE47435E1

## CPC

- H01G 9/022: Electrolytes; Absorbents
- H01G: CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE (selection of specified materials as dielectric H01B3/00; capacitors having potential barriers H10D1/62, H10K10/10)

## Abstract

An electrolyte for activating an electrolytic or electrochemical capacitor is described. The electrolyte preferably includes a mixed solvent of water and ethylene glycol having an ammonium salt dissolved therein. An acid such as phosphoric or acetic acid is used to provide a pH of about 3 to 6. The electrolyte is particularly useful for activating a ruthenium oxide/tantalum capacitor having an anode breakdown voltage in the range of 175 to 300 volts.

## Claims

### Claim 1

An electrolyte for an electrochemical energy storage device, the electrolyte consisting essentially of:
a) a mixed solvent of water and at least one second solvent selected from the group consisting of ethylene glycol, polyethylene glycol, formamide, dimethyl formamide, γ-butyrolactone, and mixtures thereof, wherein the water is present, by weight, up to about 85% and the second solvent is present, by weight, up to about 95%;
b) an ammonium salt dissolved in the mixed solvent; and
c) an acid.

### Claim 2 (depends on 1)

The electrolyte of claim 1 wherein the ammonium salt is selected from the group consisting of ammonium acetate, ammonium formate, ammonium hydrogen maleate, ammonium hydrogen phosphate, and mixtures thereof.

### Claim 3 (depends on 1)

The electrolyte of claim 1 wherein the acid is selected from the group consisting of citric acid, oxalic acid, formic acid, maleic acid, phosphoric acid, malonic acid, maltic acid, sulfuric acid, adipic acid, succinic acid, nitric acid, acetic acid, and mixtures thereof.

### Claim 4 (depends on 1)

The electrolyte of claim 1 having a pH between about 1 to about 7.

### Claim 5

An electrolyte for a capacitor, the electrolyte comprising:
a) a mixed solvent of water and ethylene glycol, wherein the water is present, by weight, up to about 85% and the ethylene glycol is present, by weight, up to about 95%;
b) a solute of ammonium acetate; and
c) a mixed acid of acetic acid and phosphoric acid.

### Claim 6 (depends on 5)

The electrolyte of claim 5 wherein the ammonium acetate is present, by weight, up to about 50%.

### Claim 7 (depends on 5)

The electrolyte of claim 5 wherein the acetic acid is present, by weight, up to about 80% and the phosphoric acid is present, by weight, up to about 6%.

### Claim 8 (depends on 5)

The electrolyte of claim 5 wherein the capacitor comprises a ruthenium oxide cathode and a tantalum anode.

### Claim 9 (depends on 8)

The electrolyte of claim 8 wherein the ruthenium oxide is provide on a titanium substrate.

### Claim 10

A capacitor, which comprises:
a) an anode of a valve metal;
b) a cathode of ruthenium oxide; and
c) an electrolyte activating the anode and the cathode, the electrolyte comprising:
i) a mixed solvent of water and ethylene glycol, wherein the water is present, by weight, up to about 85% and the ethylene glycol is present, by weight, up to about 95%;
ii) an ammonium salt dissolved in the solvent; and
iii) an acid.

### Claim 11 (depends on 10)

The capacitor of claim 10 including providing the electrolyte having ammonium acetate up to about 50%, by weight.

### Claim 12 (depends on 10)

The capacitor of claim 10 including providing the electrolyte having acetic acid up to about 80%, by weight, and phosphoric acid up to about 6%, by weight.

### Claim 13 (depends on 10)

The capacitor of claim 10 comprising a ruthenium oxide cathode and a tantalum anode.

### Claim 14 (depends on 10)

The capacitor of claim 10 wherein the ruthenium oxide is provide on a titanium substrate.

### Claim 15 (depends on 10)

The capacitor of claim 10 wherein the electrolyte includes, by weight, about 49.41% de-ionized water, about 19.45% ethylene glycol, about 15.55% ammonium acetate, about 0.31% phosphoric acid and about 15.28% acetic acid.

### Claim 16 (depends on 15)

The capacitor of claim 15 rated to about 175 volts.

### Claim 17 (depends on 10)

The capacitor of claim 10 wherein the electrolyte includes, by weight, about 44.46% de-ionized water, about 34.61% ethylene glycol, about 10.04% ammonium acetate, about 0,51% phosphoric acid and about 10.39% acetic acid.

### Claim 18 (depends on 17)

The capacitor of claim 17 rated to about 200 volts.

### Claim 19 (depends on 10)

The capacitor of claim 10 wherein the electrolyte includes, by weight, about 46.52% de-ionized water, about 36.05% ethylene glycol, about 8.29% ammonium acetate, about 0.44% phosphoric acid and about 8.70% acetic acid.

### Claim 20 (depends on 19)

The capacitor of claim 19 rated to about 250 volts.

### Claim 21 (depends on 10)

The capacitor of claim 10 wherein the electrolyte includes, by weight, about 46.59% de-ionized water, about 41.45% ethylene glycol, about 5.60% ammonium acetate, about 0.48% phosphoric acid and about 5.88% acetic acid.

### Claim 22 (depends on 21)

The capacitor of claim 21 rated to about 250 volts.

### Claim 23 (depends on 10)

The capacitor of claim 10 wherein the electrolyte includes, by weight, about 51.94% de-ionized water, about 40.29% ethylene glycol, about 3.54% ammonium acetate, about 0.59% phosphoric acid and about 3.64% acetic acid.

### Claim 24 (depends on 23)

The capacitor of claim 23 rated to about 300 volts.

### Claim 25

A method for providing an electrolyte, consisting essentially of the steps of:
a) mixing water and ethylene glycol to provide a solvent mixture, wherein the water is present, by weight, up to about 85% and the second solvent is present by weight, up to about 95%;
b) dissolving an ammonium salt in the solvent mixture; and
c) providing an acid in the solvent mixture.

### Claim 26 (depends on 25)

The method of claim 25 including selecting the ammonium salt from the group consisting of ammonium acetate, ammonium formate, ammonium hydrogen maleate, ammonium hydrogen phosphate, and mixtures thereof.

### Claim 27 (depends on 25)

The method of claim 25 including selecting the acid from the group consisting of citric acid, oxalic acid, formic acid, maleic acid, phosphoric acid, malonic acid, maltic acid, sulfuric acid, adipic acid, succinic acid, nitric acid, acetic acid, and mixtures thereof.

### Claim 28

A method for providing a capacitor, comprising the steps of:
a) providing an anode of tantalum;
b) providing a cathode of ruthenium oxide; and
c) activating the anode and the cathode with an electrolyte, the electrolyte comprising:
i) a mixed solvent of water and ethylene glycol, wherein the water is present, by weight, up to about 85% and the ethylene glycol is present, by weight, up to about 95%;
ii) an ammonium salt dissolved in the solvent; and
iii) an acid.

### Claim 29 (depends on 28)

The method of claim 28 including providing the electrolyte having ammonium acetate present, by weight, up to about 50%.

### Claim 30 (depends on 28)

The method of claim 28 including providing the electrolyte having acetic acid present, by weight, up to about 80% and phosphoric acid present, by weight, up to about 6%.

### Claim 31 (depends on 28)

The method of claim 28 comprising a ruthenium oxide cathode and a tantalum anode.

### Claim 32 (depends on 28)

The method of claim 28 wherein the ruthenium oxide is provided on a titanium substrate.

### Claim 33

An electrolyte for activating a capacitor, the electrolyte consisting essentially of:
a) a mixed solvent of water and ethylene glycol;
b) a solute of ammonium acetate present, by weight, up to about 50%; and
c) a mixed acid of acetic acid and phosphoric acid.

### Claim 34

An electrolyte for activating a capacitor, the electrolyte consisting essentially of:
a) a mixed solvent of water and ethylene glycol;
b) a solute of ammonium acetate; and
c) a mixed acid of acetic acid and phosphoric acid, wherein the acetic acid is present, by weight, up to about 80% and the phosphoric acid is present, by weight, up to about 6%.

### Claim 35

A capacitor, which comprises:
a) an anode of a valve metal;
b) a cathode of ruthenium oxide; and
c) an electrolyte activating the anode and the cathode, the electrolyte comprising:
i) a mixed solvent of water and ethylene glycol;
ii) an ammonium salt dissolved in the solvent, wherein the ammonium salt is ammonium acetate present in the electrolyte at a concentration up to about 50%, by weight; and
iii) an acid.

### Claim 36

A capacitor, which comprises:
a) an anode of a valve metal;
b) a cathode of ruthenium oxide; and
c) an electrolyte activating the anode and the cathode, the electrolyte comprising:
i) a mixed solvent of water and ethylene glycol;
ii) an ammonium salt dissolved in the solvent; and
iii) a mixed acid of acetic acid and phosphoric acid, wherein the acetic acid is present at a concentration up to about 80%, by weight, and phosphoric acid is present at a concentration up to about 6%, by weight.

### Claim 37

A capacitor, which comprises:
a) an anode of a valve metal;
b) a cathode of ruthenium oxide; and
c) an electrolyte activating the anode and the cathode, the electrolyte comprising, by weight, about 49.41% de-ionized water, about 19.45% ethylene glycol, about 15.55% ammonium acetate, about 0.31% phosphoric acid and about 15.28% acetic acid.

### Claim 38 (depends on 37)

The capacitor of claim 37 rated to about 175 volts.

### Claim 39

A capacitor, which comprises:
a) an anode of a valve metal;
b) a cathode of ruthenium oxide; and
c) an electrolyte activating the anode and the cathode, the electrolyte comprising, by weight, about 44.46% de-ionized water, about 34.61% ethylene glycol, about 10.04% ammonium acetate, about 0.51% phosphoric acid and about 10.39% acetic acid.

### Claim 40 (depends on 39)

The capacitor of claim 39 rated to about 200 volts.

### Claim 41

A capacitor, which comprises:
a) an anode of a valve metal;
b) a cathode of ruthenium oxide; and
c) an electrolyte activating the anode and the cathode, the electrolyte comprising, by weight, about 46.52% de-ionized water, about 36.05% ethylene glycol, about 8.29% ammonium acetate, about 0.44% phosphoric acid and about 8.70% acetic acid.

### Claim 42 (depends on 41)

The capacitor of claim 41 rated to about 250 volts.

### Claim 43

A capacitor, which comprises:
a) an anode of a valve metal;
b) a cathode of ruthenium oxide; and
c) an electrolyte activating the anode and the cathode, the electrolyte comprising, by weight, about 46.59% de-ionized water, about 41.45% ethylene glycol, about 5.60% ammonium acetate, about 0.48% phosphoric acid and about 5.88% acetic acid.

### Claim 44 (depends on 43)

The capacitor of claim 43 rated to about 250 volts.

### Claim 45

A capacitor, which comprises:
a) an anode of a valve metal;
b) a cathode of ruthenium oxide; and
c) an electrolyte activating the anode and the cathode, the electrolyte comprising, by weight, about 51.94% de-ionized water, about 40.29% ethylene glycol, about 3.54% ammonium acetate, about 0.59% phosphoric acid and about 3.64% acetic acid.

### Claim 46 (depends on 45)

The capacitor of claim 45 rated to about 300 volts.

### Claim 47

A method for providing a capacitor, comprising the steps of:
a) providing an anode of tantalum;
b) providing a cathode of ruthenium oxide; and
c) activating the anode and the cathode with an electrolyte, the electrolyte comprising:
i) a mixed solvent of water and ethylene glycol;
ii) an ammonium salt dissolved in the solvent, wherein the ammonium salt is ammonium acetate present, by weight, up to about 50%; and
iii) an acid.

### Claim 48

A method for providing a capacitor, comprising the steps of:
a) providing an anode of tantalum;
b) providing a cathode of ruthenium oxide; and
c) activating the anode and the cathode with an electrolyte, the electrolyte comprising:
i) a mixed solvent of water and ethylene glycol;
ii) an ammonium salt dissolved in the solvent; and
iii) a mixed acid of acetic acid and phosphoric acid, wherein the acetic acid is present at a concentration up to about 80%, by weight, and the phosphoric acid is present at a concentration up to about 6%, by weight.

### Claim 49 (depends on 33)

The electrolyte of claim 33, having a conductivity in the range of 13.7 to 47.5 mS/cm.

### Claim 50 (depends on 33)

The electrolyte of claim 33, having a resistivity in the range of 21.0 to 72.8 Ωcm.

### Claim 51 (depends on 33)

The electrolyte of claim 33, having an anode breakdown voltage in the range of 245 to 320 volts when the breakdown voltage is measured using a tantalum anode.

### Claim 52 (depends on 51)

The electrolyte of claim 51, wherein the anode breakdown voltage is measured when the electrolyte is at an operating temperature.

### Claim 53 (depends on 33)

The electrolyte of claim 33, wherein the electrolyte has:
a) a conductivity in a range of 29.6 to 47.5 mS/cm; and
b) an anode breakdown voltage in a range of 245 to 270 volts when the breakdown voltage is measured using a tantalum anode.

### Claim 54 (depends on 53)

The electrolyte of claim 53, wherein the anode breakdown voltage is measured when the electrolyte is at an operating temperature.

### Claim 55 (depends on 53)

The electrolyte of claim 53, having a pH in a range of 4.87 to 4.89.

### Claim 56 (depends on 53)

The electrolyte of claim 53, having a resistivity in a range of 21.0 to 33.8 Ωcm.

### Claim 57 (depends on 53)

The electrolyte of claim 53, wherein the electrolyte does not generate gas at 85° C.

### Claim 58 (depends on 33)

The electrolyte of claim 33, wherein the electrolyte has:
a) a conductivity in a range of 25.6 to 29.6 mS/cm; and
b) an anode breakdown voltage in a range of 270 to 275 volts when the breakdown voltage is measured using a tantalum anode.

### Claim 59 (depends on 58)

The electrolyte of claim 58, wherein the anode breakdown voltage is measured when the electrolyte is at an operating temperature.

### Claim 60 (depends on 58)

The electrolyte of claim 58, having a pH in a range of 4.83 to 4.87.

### Claim 61 (depends on 58)

The electrolyte of claim 58, having a resistivity in a range of 33.8 to 39.1 Ωcm.

### Claim 62 (depends on 58)

The electrolyte of claim 58, wherein the electrolyte does not generate gas at 85° C.

### Claim 63 (depends on 33)

The electrolyte of claim 33, wherein the electrolyte has:
a) a conductivity in a range of 18.8 to 25.6 mS/cm; and
b) an anode breakdown voltage in a range of 275 to 300 volts when the breakdown voltage is measured using a tantalum anode.

### Claim 64 (depends on 63)

The electrolyte of claim 63, wherein the anode breakdown voltage is measured when the electrolyte is at an operating temperature.

### Claim 65 (depends on 63)

The electrolyte of claim 63, having a pH in a range of 4.80 to 4.83.

### Claim 66 (depends on 63)

The electrolyte of claim 63, having a resistivity in a range of 39.1 to 53.3 Ωcm.

### Claim 67 (depends on 63)

The electrolyte of claim 63, wherein the electrolyte does not generate gas at 85° C.

### Claim 68 (depends on 33)

The electrolyte of claim 33, wherein the electrolyte has:
a) a conductivity in a range of 13.7 to 18.8 mS/cm; and
b) an anode breakdown voltage in a range of 300 to 320 volts when the breakdown voltage is measured using a tantalum anode.

### Claim 69 (depends on 68)

The electrolyte of claim 68, wherein the anode breakdown voltage is measured when the electrolyte is at an operating temperature.

### Claim 70 (depends on 68)

The electrolyte of claim 68, having a pH in a range of 4.70 to 4.80.

### Claim 71 (depends on 68)

The electrolyte of claim 68, having a resistivity in a range of 53.3 to 72.8 Ωcm.

### Claim 72 (depends on 68)

The electrolyte of claim 68, wherein the electrolyte does not generate gas at 85° C.

### Claim 73 (depends on 33)

The electrolyte of claim 33, wherein the electrolyte has:
a) a pH in a range of about 3 to 6;
b) a resistivity in a range of 21.0 to 72.8 Ωcm; and
c) an anode breakdown voltage in the range of 245 to 320 volts when the anode breakdown voltage is measured using a tantalum anode.

### Claim 74 (depends on 73)

The electrolyte of claim 73, wherein the electrolyte has said pH and said resistivity when the electrolyte is at an operating temperature.

### Claim 75 (depends on 33)

The electrolyte of claim 33, wherein:
a) water is in the range of about 44.46% to about 51.94%, by weight;
b) ethylene glycol is in the range of about 19.45% to about 41.45%, by weight;
c) ammonium acetate is in the range of about 3.54% to about 15.55%, by weight;
d) acetic acid is in the range of about 3.64% to about 15.28%, by weight; and
e) phosphoric acid is in the range of about 0.31% to about 0.59%, by weight.

### Claim 76 (depends on 75)

The electrolyte of claim 75, wherein the electrolyte has a pH in a range of 4.7 to 4.89.

### Claim 77 (depends on 75)

The electrolyte of claim 75, wherein the electrolyte has a conductivity in a range of 13.7 mS/cm to 47.5 mS/cm.

### Claim 78 (depends on 75)

The electrolyte of claim 75, wherein the electrolyte has a resistivity in a range of 21.0 to 72.8 Ωcm.

### Claim 79 (depends on 75)

The electrolyte of claim 75, wherein the electrolyte does not generate gas at 85° C.

### Claim 80

An electrolyte for a capacitor comprising a tantalum anode, the electrolyte consisting of:
a) a mixed solvent of water and ethylene glycol;
b) a solute of ammonium acetate; and
c) a mixed acid of acetic acid and phosphoric acid, wherein:
i) water is in a range of about 44.46% to about 51.94%, by weight;
ii) ethylene glycol is in a range of about 19.45% to about 41.45%, by weight;
iii) ammonium acetate is in a range of about 3.54% to about 15.55%, by weight;
iv) phosphoric acid is in a range of about 0.31% to about 0.59%, by weight; and
v) acetic acid is in a range of about 3.64% to about 15.28%, by weight.

### Claim 81

A capacitor, which comprises:
a) an anode comprising tantalum;
b) a cathode of ruthenium oxide; and
c) an electrolyte contacting the anode and the cathode, the electrolyte consisting of:
i) a mixed solvent of water and ethylene glycol, wherein the water is present, by weight, up to about 85% and the ethylene glycol is present, by weight, up to about 95%;
ii) a solute of ammonium acetate present, by weight, up to about 50%; and
iii) a mixed acid of acetic acid and phosphoric acid, wherein the acetic acid is present, by weight, up to about 80% and the phosphoric acid is present, by weight, up to about 6%.

### Claim 82 (depends on 81)

The capacitor of claim 81, wherein the electrolyte has a pH between about 1 to about 7.

### Claim 83 (depends on 81)

The capacitor of claim 81, wherein the electrolyte has a conductivity in the range of 13.7 to 47.5 mS/cm.

### Claim 84 (depends on 81)

The capacitor of claim 81, wherein the electrolyte has a resistivity in the range of 21.0 to 72.8 Ωcm.

### Claim 85 (depends on 81)

The capacitor of claim 81, wherein the electrolyte has an anode breakdown voltage in the range of 245 to 320 volts when the breakdown voltage is measured using a tantalum anode.

### Claim 86 (depends on 85)

The capacitor of claim 85, wherein the anode breakdown voltage is measured when the electrolyte is at an operating temperature.

### Claim 87 (depends on 81)

The capacitor of claim 81, wherein the electrolyte has:
a) a conductivity in a range of 29.6 to 47.5 mS/cm; and
b) an anode breakdown voltage in a range of 245 to 270 volts when the breakdown voltage is measured using a tantalum anode.

### Claim 88 (depends on 87)

The capacitor of claim 87, wherein in the electrolyte, the anode breakdown voltage is measured when the electrolyte is at an operating temperature.

### Claim 89 (depends on 87)

The capacitor of claim 87, wherein the electrolyte has a pH in a range of 4.87 to 4.89.

### Claim 90 (depends on 87)

The capacitor of claim 87, wherein the electrolyte has a resistivity in a range of 21.0 to 33.8 Ωcm.

### Claim 91 (depends on 87)

The capacitor of claim 87, wherein the electrolyte does not generate gas at 85° C.

### Claim 92 (depends on 81)

The capacitor of claim 81, wherein the electrolyte has:
a) a conductivity in a range of 25.6 to 29.6 mS/cm; and
b) an anode breakdown voltage in a range of 270 to 275 volts when the breakdown voltage is measured using a tantalum anode.

### Claim 93 (depends on 82)

The capacitor of claim 82, wherein in the electrolyte, the anode breakdown voltage is measured when the electrolyte is at an operating temperature.

### Claim 94 (depends on 82)

The capacitor of claim 82, wherein the electrolyte has a pH in a range of 4.83 to 4.87.

### Claim 95 (depends on 82)

The capacitor of claim 82, wherein the electrolyte has a resistivity in a range of 33.8 to 39.1 Ωcm.

### Claim 96 (depends on 82)

The capacitor of claim 82, wherein the electrolyte does not generate gas at 85° C.

### Claim 97 (depends on 81)

The capacitor of claim 81, wherein the electrolyte has:
a) a conductivity in a range of 18.8 to 25.6 mS/cm; and
b) an anode breakdown voltage in a range of 275 to 300 volts when the breakdown voltage is measured using a tantalum anode.

### Claim 98 (depends on 97)

The capacitor of claim 97, wherein in the electrolyte, the anode breakdown voltage is measured when the electrolyte is at an operating temperature.

### Claim 99 (depends on 97)

The capacitor of claim 97, wherein the electrolyte has a pH in a range of 4.80 to 4.83.

### Claim 100 (depends on 97)

The capacitor of claim 97, wherein the electrolyte has a resistivity in a range of 39.1 to 53.3 Ωcm.

### Claim 101 (depends on 97)

The capacitor of claim 97, wherein the electrolyte does not generate gas at 85° C.

### Claim 102 (depends on 81)

The capacitor of claim 81, wherein the electrolyte has:
a) a conductivity in a range of 13.7 to 18.8 mS/cm; and
b) an anode breakdown voltage in a range of 300 to 320 volts when the breakdown voltage is measured using a tantalum anode.

### Claim 103 (depends on 102)

The capacitor of claim 102, wherein in the electrolyte, the anode breakdown voltage is measured when the electrolyte is at an operating temperature.

### Claim 104 (depends on 102)

The capacitor of claim 102, wherein the electrolyte has a pH in a range of 4.70 to 4.80.

### Claim 105 (depends on 102)

The capacitor of claim 102, wherein the electrolyte has a resistivity in a range of 53.3 to 72.8 Ωcm.

### Claim 106 (depends on 102)

The capacitor of claim 102, wherein the electrolyte does not generate gas at 85° C.

### Claim 107 (depends on 81)

The capacitor of claim 81, wherein the electrolyte has:
a) a pH in a range of about 3 to 6, a resistivity in a range of 21.0 to 72.8 Ωcm, and an anode breakdown voltage in the range of 245 to 320 volts; and
b) the anode breakdown voltage is measured using a tantalum anode.

### Claim 108 (depends on 107)

The capacitor of claim 107, wherein the electrolyte has said pH and said resistivity when the electrolyte is at an operating temperature.

### Claim 109 (depends on 81)

The capacitor of claim 81, wherein in the electrolyte:
a) water is in the range of about 44.46% to about 51.94%, by weight;
b) ethylene glycol is in the range of about 19.45% to about 41.45%, by weight;
c) ammonium acetate is in the range of about 3.54% to about 15.55%, by weight;
d) acetic acid is in the range of about 3.64% to about 15.28%, by weight; and
e) phosphoric acid is in the range of about 0.31% to about 0.59%, by weight.

### Claim 110 (depends on 109)

The capacitor of claim 109, wherein the electrolyte has a pH in a range of 4.7 to 4.89.

### Claim 111 (depends on 109)

The capacitor of claim 109, wherein the electrolyte has a conductivity in a range of 13.7 mS/cm to 47.5 mS/cm.

### Claim 112 (depends on 109)

The capacitor of claim 109, wherein the electrolyte has a resistivity in a range of 21.0 to 72.8 Ωcm.

### Claim 113 (depends on 109)

The capacitor of claim 109, wherein the electrolyte does not generate gas at 85° C.

### Claim 114 (depends on 33)

The electrolyte of claim 33, having a pH between about 1 to about 7.

### Claim 115

A capacitor, which comprises:
a) an anode of tantalum;
b) a cathode of ruthenium oxide; and
c) an electrolyte contacting the anode and the cathode, the electrolyte consisting of:
i) a mixed solvent of water and ethylene glycol;
ii) a solute of ammonium acetate present, by weight, up to about 50%; and
iii) a mixed acid of acetic acid and phosphoric acid.

### Claim 116

A capacitor, which comprises:
a) an anode of tantalum;
b) a cathode of ruthenium oxide; and
c) an electrolyte contacting the anode and the cathode, the electrolyte consisting of:
i) a mixed solvent of water and ethylene glycol;
ii) a solute of ammonium acetate; and
iii) a mixed acid of acetic acid and phosphoric acid, wherein the acetic acid is present at a concentration up to about 80%, by weight, and phosphoric acid is present at a concentration up to about 6%, by weight.

### Claim 117

A method for providing a capacitor, comprising the steps of:
a) providing an anode of tantalum;
b) providing a cathode of ruthenium oxide; and
c) contacting the anode and the cathode with an electrolyte, the electrolyte consisting of:
i) a mixed solvent of water and ethylene glycol;
ii) a solute of ammonium acetate present, by weight, up to about 50%; and
iii) a mixed acid of acetic acid and phosphoric acid.

### Claim 118

A method for providing a capacitor, comprising the steps of:
a) providing an anode of tantalum;
b) providing a cathode of ruthenium oxide; and
c) contacting the anode and the cathode with an electrolyte, the electrolyte consisting of:
i) a mixed solvent of water and ethylene glycol;
ii) a solute of ammonium acetate; and
iii) a mixed acid of acetic acid and phosphoric acid, wherein the acetic acid is present at a concentration up to about 80%, by weight, and the phosphoric acid is present at a concentration up to about 6%, by weight.