A MULTI-ELEMENT ELECTROCHEMICAL CAPACITOR
AND A METHOD FOR MANUFACTURINGTHE SAME
FIELD OF THE INVENTION
The invention relates to electrical engineering, in particular, to the manufacture of
electrochemical capacitors having a combined charge storage mechanism and other similar
rechargeable electric energy storages.
BACKGROUND OF THE INVENTION
A prior art multi-element capacitor (see: Application PCT WO 2009103661, cl. H01G
9/155, published on August 27, 2009, 34 pages) comprises at least two adjacent composite
electrodes separated by a spacing d and at least one composite electrode common for the
aforesaid electrodes and held apart therefrom by a separator, the composite electrodes being
coiled together into a roll.
This design gives rise to unavoidable problems in providing reliable low-resistance
contact between the electrode and the commutator. Furthermore, discontinuity of the electrode
material may cause undesirable reaction between the electrolyte and the commutator material
that may, in turn, reduce the operating voltage of the capacitor by the electrochemical
decomposition potential of the commutator. Absence of insulation between the adjacent
capacitor electrodes is another major deficiency of the design reducing voltage and, therefore,
specific energy of the capacitor. As a result, when capacitor sections are connected in series the
potential differentials of the electrodes may be double the operating voltage of the capacitor
elements. This is likely to initiate electrochemical electrode reactions limiting the lifetime of the
capacitor.
A prior art method for manufacturing a multi-element capacitor is described in
Application PCT WO 2009103661, cl. H01G 9/155, published on August 27, 2009, 34 pages.
According to the prior art method, an electrode is placed between two separators that are actually
separating bands, with two composite electrodes placed at a distance d between them on the top
band. The bands and the electrodes are then coiled into rolls.
The prior art invention is disadvantageous because the multi-element capacitor comprises
individual components in the form of spaced electrodes that are difficult to be combined into a
multi-element assembly, particularly in a continuous roll-making process. The use of a
multilayered composite structure comprising an electrode applied to the metal commutator
l
surface is another disadvantage of the prior art invention.
SUMMARY OF THE INVENTION
It is an object of the claimed invention to improve the structural elements of a device and
develop a sectional rolled multi-element electrochemical capacitor free of the deficiencies of the
closest prior art invention and capable of attaining specific characteristics making it a practicable
technological and economic option to use.
Improving the specific characteristics of the electrochemical electric energy storage,
maintaining stability of the specific characteristics, and extending the service life are the
common technical effect of both the method and the device.
The technical result of this invention is achieved in a multi-element electrochemical
capacitor that comprises at least one layer of electrical insulation film having alternating
electrode sheets of opposite polarities spaced apart by a porous ion-permeable separator that are
placed on the electrical insulation film, the film and the alternating sheets being coiled into a roll
and impregnated with electrolyte. Moreover, each electrode sheet is a substrate made of
nonwoven polymer material of a high pore ratio and provided with at least one electrode attached
to one side or both sides thereof, or therein, said electrode being an electrochemically active
layer containing nano-sized particles of metals or compounds thereof, or redox polymers.
Furthermore, the electrodes of the opposite polarity electrode sheets are made of nano-structured
carbon materials of different types. One of the nano-structured carbon materials has a maximum
possible specific surface area and a relatively low conductance, while the other material has a
relatively large specific surface area and a relatively high conductance. The capacitor further
comprises contact electrodes connectable to the central and peripheral electrodes.
The substrate may be made of an electron-impermeable, ion-impermeable material that is
chemically and electrochemically inactive in the material electrolyte.
Carbon nano-tubes of only a few layers may serve as one of the nano-structured
electrodes, and activated carbon, activated carbon black, carbon impregnated with metals, and
nano-porous carbon material based on carbides of metals such as Ti, B, and Si may be used as
the other nano-structured carbon material.
The material of the positive electrode of the electrode sheet may contain nano-sized
particles of metals such as manganese, mercury, silver, and nickel, and metal compounds such as
manganese oxide, manganese hydroxide, mercury oxide, silver oxide, lead oxide, lead sulfate,
nickel hydroxide, and lithium-cobalt oxide. The material of the negative electrode may contain
nano-sized particles of metals such as zinc, lead, cadmium, iron, and lithium, and metal
compounds such as zinc hydroxide, zinc chloride, lead sulfate, cadmium hydroxide, and iron
hydroxide.
The electrode sheet in contact with the electrical insulation film is placed with its
electrochemically active layer up with respect to the electrical insulation film, and the next
electrode sheet is placed thereon with a shift equal to half the width of the electrochemically
active layer thereof such that the electrochemically active layers of the electrode sheets are
facing each other and are interspaced by a porous ion-permeable separator.
The electrodes of the electrode sheet may be attached to the substrate in succession.
The outer surface of the roll may be connected to a peripheral electrode by a contact
electrode such that the roll is placed in the peripheral electrode that is a length of a metal rube.
The end faces of the peripheral electrode may be provided with covers.
The above technical effect is also achieved in a method for manufacturing a multi¬
element electrochemical capacitor that comprises preparing electrode mixtures containing nanostructured
carbon materials of various types. One of the nano-structured carbon materials has the
largest possible specific surface area and a relatively low conductance, while the other material
has a relatively large specific surface area and a relatively high conductance. The method also
comprises manufacturing opposite-polarity electrode sheets by applying an electrode mixture to
one side or both sides of, and placing it within, the substrate made of a nonwoven polymer
material of a high pore ratio, covering the substrate with an electrochemically active layer
containing nano-sized particles of metals or compounds thereof, or redox polymers. Oppositepolarity
electrode sheets interspaced by a porous ion-permeable separator are placed successively
on at least one layer of electrical insulation film, coiled into a roll around a central electrode, the
outer surface of the roll is connected to a peripheral electrode, and the roll is impregnated with
electrolyte.
According to the method, the electrical insulation film layers and alternating oppositepolarity
electrodes sheets interspaced by an ion-permeable separator placed on the film are
spread in parallel planes.
The outer surface of the roll may be connected to a peripheral electrode by a contact
electrode that serves as the outer surface of the roll, and the rolls is placed in the peripheral
electrode. Furthermore, after the roll has been impregnated with electrolyte, the end faces of the
peripheral electrode may be closed with covers made of an electrical insulation material. The
central and peripheral tube electrodes may be made of aluminum or alloys thereof, and the
covers are made of plastics.
Carbon nano-tubes of only a few layers are used in the claimed method as one of the
nano-structured carbon materials, and activated carbon, activated carbon black, metalimpregnated
carbon, and nano-porous carbon material on the basis of carbides, such as Ti, B, and
Si carbides, can be used as the other nano-structured carbon material.
The method also provides for the use of carbon nano-tubes of a few layers obtained by
pyrolysis of a mixture of a gaseous hydrocarbon and hydrogen and having a size of 5 to 50 nm, a
specific surface area of 500 to 1,000 m /g, and specific conductance of 10-100 Sm/cm. Pyrolysis
of the mixture of the gaseous hydrocarbon and hydrogen is carried out at a temperature
maintained within the range of 650 to 900°C and pressure within the range of 0. to .0 MPa, on
a catalyst such as compounds based on cobalt and molybdenum or nano-structured magnesium
oxide, and natural gas, or propane, or butane, or ethylene is used as the gaseous hydrocarbon.
The method may use carbon nano-tubes of a few layers obtained by pyrolysis of a
mixture of an aromatic hydrocarbon and alcohol. Pyrolysis of a mixture of an aromatic
hydrocarbon and alcohol is carried out at a temperature maintained within the range of 650 to
900°C and pressure within the range of 0.1 to 1.0 MPa, on a catalyst such as compounds based
on iron, nickel, and magnesium oxide, and benzene and toluene are used as an aromatic
hydrocarbon, with ethanol used as alcohol.
Furthermore, carbon nano-tubes of a few layers are further treated, following
manufacture, with oxidizing agents, ultrasound, or water in supercritical conditions.
The method may use activated carbons produced by forming a synthetic monomer in
fluid followed by carbonization and high-temperature vapor-gas activation at a temperature of
600 to 1,100°C.
The method may use nano-porous carbon materials produced from boron, titanium, and
silicon carbides. They are further subjected to high-temperature thermochemical treatment with
chlorine at a temperature of 600 to 1,200°C.
To prepare an electrode mixture, carbon nano-tubes of a few layers and activated carbon
are mixed at a ratio of 1:3 to 3:1 in ball mills until a grain size of 10 to 100 nm is achieved, sifted
on typical 100 nm mesh sieves, and treated by ultrasound to give maximum uniformity to the
electrode mixture.
The nano-tubes and carbon black are mixed by layer-by-layer centrifuging in a
centrifuge.
The positive electrode of the electrode sheet is manufactured from nano-sized particles of
metals such as manganese, mercury, silver, and nickel, and metal compounds such as manganese
dioxide, manganese hydroxide, mercury oxide, silver oxide, lead oxide, lead sulfate, nickel
hydroxide, and lithium-cobalt oxide. The negative electrode is manufactured from nano-sized
particles of metals such as zinc, lead, cadmium, iron, and lithium, and metal compounds such as
zinc hydroxide, zinc chloride, lead sulfate, cadmium hydroxide, and iron hydroxide.
An electrode sheet is obtained by covering a substrate with a suspension comprising an
electrode mixture dispersed by ultrasound in an organic solvent, which is isopropanol or ethanol.
The electrode mixture may also be applied to a substrate in powder form under the effect
of electrostatic forces.
Following the application of the electrode mixture, the resultant electrode sheet is placed
on a contact electrode such as graphite foil, whereupon it is heated to a temperature of 120 to
150°C and subjected to pressure ranging from 0.5 to 1.0 MPa. The contact electrodes are secured
to peripheral electrode sheets.
A porous separator of one to four layers thick may be provided by a track membrane
made of polymer film 3 to 5 mpi thick, with a pore ratio of 20 to 40% and pore size of 0.05 to
0.1 mpi, or a sheet of nonwoven material such as polypropylene 10 m h thick at a density of 15 to
40 mg/cm2, or an ion-permeable polymer membrane made of polybenzimidazole 10 to 15 mpi
thick, impregnated with electrolyte and containing 3 to 10 mass parts of electrolyte.
Organic electrolyte comprising an organic salt solution containing ammonium or
imidazole base cations and anions including tetrafluoroborate, hexafluorophosphate or
triflatimide, or bistriflatimide, or tris(pentafluoroethyl)trifluorophosphate, in acetonitrile, or
propylenecarbonate, or formamide, or a mixed electrolyte containing a solution of zinc chloride
in acetonitrile, or inorganic electrolyte as an aqueous solution of a potassium alkali. The roll may
be impregnated with electrolyte in a vacuum chamber under a residual pressure of 10 Pa.
The method may provide for coiling several parallel electrode sheets into a roll that is
placed in a container of parallelepiped or cylindrical shape.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic view of a multi-element electrochemical capacitor;
FIG. 2 is a diagrammatic view of the structure of a multi-element electrochemical
capacitor, showing diagrammatically the stacking of electrical insulation film and electrode
sheets, with a porous separator placed between them;
FIG. 3 is a diagrammatic view of the structure of a multi-element electrochemical
capacitor, showing the location of electrodes of an electrode sheet coiled into a roll;
FIG. 4 is a view of an electrode made of a composite nano-structured carbon material
consisting of activate FAS carbon and carbon nano-tubes;
FIG. 5 illustrates an example of a cyclic volt-amperogram of a three-element capacitor
manufactured by the claimed method and comprising two electrode sheets, each of them having
two electrodes of a composite carbon material attached thereto and spaced by a porous separator
made of PVDF track membranes impregnated with ionic fluid of l-butyl-3-methyl-imidazole
tetrafluoroborate;
FIG. 6 illustrates an exemplary charge-discharge cycle of a 60-element capacitor having
1M of KOH electrolyte (charge current 0.4 A); and
FIG. 7 illustrates an example of calculation of charge-discharge energy of a 15-element
capacitor having EMIM BF4 electrolyte.
DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION
The multi-element electrochemical capacitor (FIGs. 1 to 3) comprises a layer of electrical
insulation film 40, an electrode sheet 10, an electrode sheet 20, and a porous separator 30 placed
between electrode sheets 20 and 10. Electrode sheets 10 and 20 each consist of a substrate 11
and electrodes 1 and 2 attached thereto in succession. The thickness of substrate 11 in the
specific embodiments of the claimed electrochemical capacitor may be selected within the range
of 5 to 150 mh , preferably from 10 to 50 m , and the thickness of the electrochemically active
layers of electrodes 1 and 2 varies from 100 to 500 mp , preferably from 300 to 400 m .
FIG. 3 illustrates the principle of making a roll 50 by coiling a band around a central
electrode 13. Lengths of electrode sheets 10 and 20 are placed on the substrate with a shift of
one-half of the electrode width, their electrochemically active layers facing each other, so as to
produce an alternating pair of opposite-polarity electrodes 1 and 2. The resultant roll 50 is placed
in a peripheral electrode 14 provided with covers 60 at the end faces thereof. Covers 60 of
electrical insulation material are normally inserted after electrode roll 50 has been impregnated
with electrolyte. Electrode sheets 10 and 20 spaced by a porous separator 30 as described above
are placed on electrical insulation film 40 and are subjected to heat treatment under pressure
(lamination). The resultant band is coiled into roll 50 comprising one layer of electrical
insulation film 40 and lengths of electrodes sheets 10 and 20 placed thereon in opposite
directions and shifted relative to each other to half the width of electrodes 1 and 2 and having
porous separator 30 placed between them.
To obtain an electrode roll, contact electrodes 12 of the electrode sheet extend beyond the
endmost electrodes placed at the opposite ends of the resultant band. One contact electrode 12 is
connected to central electrode 13 by coiling it around central electrode 13 of the band. The other
contact electrode forms the outer surface of the roll and connects the outer surface of electrode
roll 50 to a peripheral electrode 14. This design provides reliable electrical contact with
peripheral electrode 14 and helps seal off the interior of the multi-element capacitor. The
outlying electrodes of the electrode sheet are brought into contact with contact electrodes 12
made of a conductive carbon material, for example, graphite foil.
Central electrode 13 and peripheral electrode 14 are made of metal tubing of, for
example, aluminum and its alloys, and covers 60 of electrical insulation material, for example,
plastics, are inserted from both end faces of the electrode roll between the central and peripheral
electrodes. Typically, covers 60 of electrical insulation material are inserted after electrode roll
50 has been impregnated with electrolyte. The contact between cover 60 and end face edges of
coiled electrode roll 0 are sealed, for example, with a compound based on epoxy resin.
Electrodes 1 and 2 are obtained by chemical and/or electrochemical deposition of a
dispersion of the aforesaid electrode mixture prepared in an organic electrolyte (ionic fluid) on
the polymer frame of the electrode sheet at a weight ratio of the electrode material to electrolyte
between 1:1 and 1:2 by ultrasonic dispersion, with or without solvents added, followed by
vacuum treatment of the dispersion prepared as above.
The electrochemically active surface material of the positively charged working part of
the electrodes is obtained by adding, in a chemical and/or electrochemical process, nano-sized
particles of metals, such as, for example, manganese, silver, nickel, and lead, or metal
compounds, for example, manganese oxide and nickel hydroxide, and redox polymers, to the
composite electrode mixture comprising, for example, carbon nano-tubes of a few layers and
activated carbon black.
The electrochemically active surface material of the negatively charged working part of
the electrodes is obtained by adding, in a chemical and/or electrochemical process, nano-sized
particles of metals, for example, zinc or iron, and metal compounds, for example, zinc
hydroxide, iron hydroxide, and lead dioxide, or redox polymers, to the composite electrode
mixture comprising, for example, carbon nano-tubes of a few layers and activated carbon black.
The aforesaid chemical and/or electrochemical treatment of an electrochemically active
material in the specific embodiments of the claimed electrochemical capacitor may be carried out
in aqueous solutions of sulfuric or phosphoric acid at a concentration of 1 to 30 mass %, in
aqueous and nonaqueous solutions of potassium, sodium or ammonium salts of organic and
inorganic acids, for example, sulfates, chlorides, fluorides, phosphates, diphosphates, acetates,
tartrates, and formates of alkaline metals, or ammonium, or complex compounds, and also in
aqueous or water-organic solutions of alkalis at concentrations of 1 to 70 mass %.
Addition of metals, their compounds, or redox polymers modifying the structure and
composition of the surface layer of the positively charged and negatively charged working parts
of the electrodes may improve the performance characteristics of the electrodes and the capacitor
as a whole, such as energy output growth as a result of reversible redox reactions, higher
operating voltage, and improved mechanical properties of the coating. The content of metals,
their compounds, or redox polymers is not, however, to go over a certain limit that, if exceeded,
causes the strength of the electrochemically active layer to decline. This limit is ascertained
experimentally in each specific case.
Organic electrolyte is added by applying an aerosol dispersion of organic electrolyte, with
or without solvent, to the electrode sheet prior to coiling, or by impregnating the composite
electrode material and porous separator 30 during the coiling process, or by preimpregnating the
composite electrode material in supercritical C0 2 conditions, or by placing the multi-element
capacitor coiled into roll 50 in an electrolyte bath, or by impregnating the composite electrode
material and porous separator 30 of the multi-element capacitor coiled into roll 50 in
supercritical C0 2 conditions.
The electrolyte used for impregnating electrode roll 50 is an organic electrolyte that is an
organic salt solution based on, for example, ammonium tetra-alkyl or dialkyl-imidazole
tetrafluoroborate, in an organic solvent, for example, acetonitrile, or a mixed electrolyte
comprising a solution of an inorganic salt, for example, zinc chloride, in an organic solvent, for
example, acetonitrile, or an inorganic electrolyte, for example, aqueous solutions of potassium
alkali. Electrode roll 50 is impregnated with electrolyte in a vacuum chamber, for example,
under residual pressure of 10 Pa.
The electrochemical capacitor may comprise one electrode sheet or several parallel
electrode sheets 10 and 20. One electrode sheet or several parallel electrode sheets 10 and 20
impregnated with electrolyte may be placed in a parallelepiped-shaped casing.
An electrochemical capacitor assembled as described above in ready for immediate use.
To improve the energy characteristics of the electrochemical capacitor, it is operated at elevated
temperatures within the range of 30 to 65°C, preferably at 60°C. The electrochemical capacitor is
charged with relatively high currents in the galvanostatic mode. Individual electrochemical
capacitors are connected into a battery in a parallel-series circuit that achieves optimal energy
and power output of the electric charge accumulated by the capacitor.
Furthermore, in contrast to the immediate prior art, the electrochemical capacitor
improves specific characteristics (specific energy output, energy density, current density, specific
power, specific charge, and voltage) in comparison with conventional electrochemical capacitors
having carbon electrodes and using a twin-layer charge accumulation mechanism, or chemical
current sources using reversible redox chemical reactions, at approximately equal material costs.
This helps achieve the claimed objective of developing an electrochemical capacitor having
practicable specific characteristics that make it a suitable technical and economic choice for use.
The feasibility of the claimed multi-element electrochemical capacitor is illustrated by the
following examples:
Example 1
Assembly of a three-element capacitor. Electrodes measuring 80 45 mm2 were made of
a mixture of activated FAS and UNT carbon by benzene pyrolysis on a catalyst containing
ferrocene, with ASCG silica gel added thereto, at a ratio of 1:1:1, of a total weight of 0.140 g.
Following ball mill grinding for 20 minutes and preliminary treatment of the carbon material
solution in ethanol for 10 minutes by a 10 W ultrasonic source, they were applied to GF-D
graphite foil by aerosol dispersion. The adjacent electrodes were spaced 5 mm apart. The
electrodes were spaced by a separator consisting of four layers of track membrane having a pore
ratio of 1.7% and a thickness of 23 m . The electrodes and membrane were impregnated with
EMIM BF4 (Merck) ionic fluid. FIG. 5 shows a cyclic volt-amperogram at a charge-discharge
rate of 50 mV/sec. The specific parameters calculated on the basis of CVA data were as follows:
charge voltage dU = 9 V, C = 0.4 F; Ech g = 47.7 W.hr/kg, and Edischar ge = 32.2 W.hr kg of the
weight of the active electrode material, and efficiency = 67.6%.
Example 2
Assembly of a 60-element capacitor. Electrodes measuring 200 * 85 mm2 were made of
activated carbon (coco base) and UNT obtained by toluene pyrolysis on a catalyst containing
ferrocene and carbon black added thereto at a ratio of 2:2:1. Following ball mill grinding for 20
minutes and preliminary treatment of the carbon material solution in ethanol for 10 minutes by a
10 ultrasonic source, they were applied to GF-D graphite foil by aerosol dispersion in a layer
140 m thick. The electrode material weighed 46.8 g. The adjacent electrodes were spaced 5 mm
apart. The electrode were spaced apart by a porous separator consisting of four layers of track
membrane having a pore ratio of 11.7% and thickness of 23 m h. The electrodes and membrane
were impregnated with electrolyte, 1 of KOH solution. When the specific parameters were
calculated on the basis of data of the voltage and current versus time dependence, the energy
stored was 2.7 W.hr/kg of active electrode mass.
Example 3
Assembly of a one-element capacitor. Electrodes measuring 40 40 mm were made of a
mixture of activated PFT and UNT carbon obtained by methane pyrolysis on a catalyst
containing cobalt and molybdenum at a ratio of 1:1, with Pb deposited on the anode and Pb0 2 on
the cathode. Following preliminary treatment of the carbon material solution in ethanol for 10
minutes by a 10 W ultrasonic source, they were applied to GF-D graphite foil by aerosol
dispersion in a layer 80 mp thick. The electrode material weighed 115 mg. The electrodes were
spaced apart by a porous separator consisting of one layer of track membrane having a pore ratio
of 11.7% and thickness of 23 mp . The electrodes and membrane were impregnated with
electrolyte, a 4.7 M aqueous solution of sulfuric acid. When charged with 2 V voltage, the
capacitor stored energy of 27.7 W.hr/kg of active electrode mass.
Example 4
Assembly of a 15-element capacitor. Electrodes measuring 40 85 mm2 were made of
activated PFT-0 and UNT carbon black obtained by methane pyrolysis on a catalyst containing
cobalt and molybdenum at a ratio of 5:1, to which 20% of GSM-2 graphite was added.
Following ball mill grinding for 20 minutes and preliminary treatment of the carbon material
solution in ethanol for 10 minutes by a 10 W ultrasonic source, they were applied to a nonwoven
polypropylene sheet by aerosol dispersion in a layer 90 mhi thick. The electrode material
weighed 1.1 g and was placed on lengths of GF-D graphite foil. The distance between the
adjacent electrodes was 5 mm. The electrodes were spaced apart by a porous separator consisting
of two layers of track membrane having a pore ratio of 11.7% and thickness of 23 m . The
electrodes and membrane were impregnated with electrolyte, EMIM BF4 (Merck) ionic fluid.
When the specific parameters were calculated on the basis of the data for voltage and current
versus time dependence, the discharge energy accumulated was 4 1 W.hr/kg of active electrode
mass for the electrode charge voltage of 45 V and 107 W.hr/kg of active electrode mass for the
electrode charge voltage of 60 V. The specific power on discharge was 13.5 kW/kg of active
electrode mass for the electrode charge voltage of 45 V, and 14.3 kW/kg of active electrode mass
for the electrode charge voltage of 65 V.

CLAIMS
What is claimed is:
1. A multi-element electrochemical capacitor comprising at least one layer of electrical
insulation film and alternating opposite-polarity electrode sheets placed thereon in succession
and spaced apart by a porous ion-permeable separator, the electrode sheets and porous separator
being coiled into a roll, each of the electrode sheets being a substrate of nonwoven polymer
material having a high pore ratio and provided with at least one electrode attached to one side or
both sides thereof, or embedded within the substrate in the form of an electrochemically active
layer containing nano-sized particles of metals or their compounds, or redox polymers, the
electrodes of the opposite-polarity electrode sheets being made of nano-structured carbon
materials of different types, one of the nano-structured carbon materials having the largest
possible specific surface area and a relatively low conductance, and the second nano-structured
materials having a relatively large specific surface area and a relatively high conductance, the
capacitor further comprising contact electrodes adapted to be connected to the central and
peripheral electrodes.
2. The capacitor as claimed in claim 1, wherein the substrate is made of an electronimpermeable
and ion-impermeable material that is chemically and electrochemically inactive in
electrolyte.
3. The capacitor as claimed in claim 1, wherein carbon nano-tubes of a few layers serve
as one nano-structured material, and activated carbon, activated carbon black, metal-impregnated
carbon, and nano-porous material based on carbides of metals such as Ti, B, and Si.
4. The capacitor as claimed in claim 1, wherein the material of the positive electrode of
the electrode sheet contains nano-sized particles of metals such as manganese, mercury, silver,
and nickel, metal compounds such as manganese dioxide, manganese hydroxide, mercury oxide,
silver oxide, lead oxide, lead sulfate, nickel hydroxide, and lithium-cobalt oxide, and the material
of the negative electrode contains nano-sized particles of metals such as zinc, lead, cadmium,
iron, and lithium, and metal compounds such as zinc hydroxide, zinc chloride, lead sulfate,
cadmium hydroxide, and iron hydroxide.
5. The capacitor as claimed in claim 1, wherein the electrode sheet in contact with the
electrical insulation film is placed with its electrochemically active layer facing up from the
electrical insulation film, and the next electrode sheet is shifted to half the width of its
electrochemically active layer, the electrochemically active layers of the electrode sheets facing
each other and being interspaced by a porous ion-permeable separator.
6. The capacitor as claimed in claim 1, wherein the electrodes of the electrode sheet are
attached to the substrate in succession.
7. The capacitor as claimed in claim 1, wherein the outer surface of the roll is connected
to the peripheral electrode by a contact- electrode, the roll being placed in the peripheral electrode
made of metal tubing, the end faces of the peripheral electrode being provided with covers.
8. A method for manufacturing a multi-element electrochemical capacitor, comprising
preparing electrode mixtures containing nano-structured carbon materials of different types, one
of the nano-structured carbon materials having the largest possible specific surface area and a
relatively low conductance, and the other nano-structured carbon material having a relatively
large specific surface area and a relatively high conductance; manufacturing opposite-polarity
electrode sheets by applying an electrode mixture to one side or both sides of, or embedding it
within, a substrate made of a nonwoven polymer material having a high pore ratio; producing on
said substrate an electrochemically active layer containing nano-sized particles of metals or their
compounds, or redox polymers; placing successively on at least one layer of the electrical
insulation film opposite-polarity electrode sheets spaced apart by a porous ion-permeable
separator; coiling the layers into a roll around a central electrode; connecting the outer surface of
the roll to a peripheral electrode; and impregnating the roll with electrolyte.
9. The method as claimed in claim 8, wherein the outer surface of the roll is connected to
the peripheral electrode by a contact electrode that forms the outer surface of the roll inserted
into the peripheral electrode, the end faces of the peripheral electrode being closed with covers
made of electrical insulation material after the roll has been impregnated with electrolyte.
10. The method as claimed in claim 9, wherein the central and peripheral electrodes are
made of tubing of aluminum and alloys thereof and the covers are made of plastics.
11. The method as claimed in claim 8, wherein carbon nano-tubes of a few layers are
used as one nano-structured carbon material, and activated carbon, activated carbon black, metalimpregnated
carbon, and nano-porous carbon material based on carbides of metals such as Ti, B,
and Si is used as the other nano-structured carbon material.
12. T e method as claimed in claim 11, using carbon nano-tubes of a few layers produced
by pyrolysis of a mixture of a gaseous hydrocarbon and hydrogen and measuring 5 to 50 nm,
specific surface area of 500 to 1,000 m2/g, and specific conductance of 10 to 100 Sm/cm.
13. The method as claimed in claim 1 , wherein pyrolysis of a mixture of a gaseous
hydrocarbon and hydrogen is carried out at a temperature maintained within the range of 650 to
900°C and pressure within the range of 0.1 to 1.0 MPa, compounds based on cobalt and
molybdenum are used as a catalyst, and natural gas or propane, or butane, or ethylene is used as
the gaseous hydrocarbon.
14. The method as claimed in claim 11, using carbon nano-tubes of a few layers produced
by pyrolysis of a mixture of an aromatic hydrocarbon and alcohol.
15. The method as claimed in claim 14, wherein pyrolysis of a mixture of an aromatic
hydrocarbon and alcohol is carried out at a temperature maintained within the range of 650 to
900°C and pressure within the range of 0.1 to 1.0 MPa, compounds based on iron and nickel and
magnesium oxide are used as a catalyst, benzene and toluene are used as an aromatic
hydrocarbon, and ethanol is used as alcohol.
16. The method as claimed in any of claims 1 to 15, wherein the carbon nano-tubes of a
few layers are subjected to further treatment by oxidizing agents, ultrasound, and water in
supercritical conditions.
17. The method as claimed in claim 11, further using activated carbons produced by wet
formation of a synthetic monomer followed by carbonization and high-temperature vapor-gas
activation at a temperature of 600 to 1,000°C.
18. The method as claimed in claim 11, further using nano-porous carbon materials
obtained from boron, titanium, and silicon carbides that are subjected to further high-temperature
thermochemical treatment with chlorine at a temperature to 600 to 1,200°C.
19. The method as claimed in claim 11, wherein an electrode mixture is prepared by
mixing carbon nano-tubes of a few layers and activated carbon at a ratio of 1:3 to 3:1 in ball
mills producing grains measuring about 10 to 100 nm that are sifted on screens with a typical
mesh size of 100 nm and treated with ultrasound to give maximum uniformity to the electrode
mixture.
20. The method as claimed in claim 8, wherein the positive electrode of the electrode
sheet is manufactured from nano-sized particles of metals such as manganese, mercury, silver,
and nickel, and metal compounds such as manganese dioxide, manganese hydroxide, mercury
oxide, silver oxide, lead oxide, lead sulfate, nickel hydroxide, and lithium-cobalt oxide, and the
negative electrode is manufactured from nano-sized particles of metals such as zinc, lead,
cadmium, iron, and lithium, and metal compounds such as zinc hydroxide, zinc chloride, lead
sulfate, cadmium hydroxide, and iron hydroxide.
21. The method as claimed in claim 8, wherein an electrode sheet is manufactured by
applying a suspension of an electrode mixture dispersed by ultrasound in an organic solvent to a
substrate.
22. The method as claimed in claim 21, wherein isopropanol or ethanol is used as an
organic solvent.
23. The method as claimed in claim 8, wherein the electrode mixture is applied in powder
form to the substrate under the effect of electrostatic forces.
24. The method as claimed in claim 8, wherein the resultant electrode sheet is placed,
after the electrode mixture has been applied thereto, on a contact electrode such as graphite foil
and heated to a temperature between 120 and 150°C and pressed at a pressure of 0.5 to 1.0 MPa.
25. The method as claimed in claim 8, wherein the porous separator made up of one to
four layers is a track membrane manufactured from polymer film 3 to 5 mp thick, at a pore ratio
of 20 to 40%, and pore size of 0.05 to 0.1 mp , or a sheet of nonwoven polymer material such as
polypropylene 10 m thick at a density of 1 to 40 mg/cm2, or ion-permeable polymer
membrane manufactured from polybenzimidazole 10 to 15 mh thick impregnated with
electrolyte and containing 3 to 10 mass parts of electrolyte.
26. The method as claimed in claim 8, wherein the electrolyte used for impregnating the
roll is an organic electrolyte comprising an organic salt solution containing cations based on
ammonium or imidazole, and anions including tetrafluoroborate, hexafluorophosphate or
triflatimide, or bistriflatimide, or tris(pentafluoroethyl)trifluorophosphate in acetonitrile, or
propylene carbonate, or formamide, or an inorganic electrolyte such as an aqueous solution of a
potassium alkali.
27. The method as claimed in claim 8 or 26, wherein the roll is impregnated in electrolyte
in a vacuum chamber under a residual pressure of 10 Pa.
28. The method as claimed in claim 8, wherein several parallel electrode sheets are coiled
into a roll and placed in a casing in the form of a parallelepiped or cylinder.