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Nanoparticles
A patent was filed in March 2005 by the
inventor, Dr. Sung H. Choi. All rights have been
assigned to Enable IPC Corporation. The patent is still in review at the
US Patent Office.
As of May 2007, the Company had not heard from the patent office (we are
told that the
time lag is not unusual these days, especially for a
nanotechnology-related patent
application). Foreign rights under the PCT have also been filed.
Capacitors, which used to be known as “condensers” are
devices that store energy electric charges and
release them when they are needed. They are very similar to batteries,
except for one major difference:
batteries are good at storing energy, but not so good at
releasing power. Capacitors can release a lot of power at
once, but are poor at storing energy. Capacitors were first
developed in 1745 by a German inventor named Ewald George
von Kleist. They consist of two plates and a separator. The
plates are charged by a power source and, when the power is
needed, they can send out their entire charge almost
instantaneously.
In May 2007, Enable IPC entered into a license option agreement with the
University of Wisconsin that
leads to an exclusive license of the ultra capacitor technology for the
consumer electronics market.
Using Nan wires (i.e., tiny poles that stand on end) can increase the
surface area of a
battery's electrode. This allows for a greater amount of power.
As engineering innovations continue to advance ultracapacitors, their
enhanced performance capabilities are expected to hasten the convergence
of batteries and ultracapacitors—strengthening the combination of both
specific energy storage and pulse power design in future applications.
Electric double-layer capacitors, also known as super
capacitors, electrochemical double layer capacitors EDLCs or ultra
capacitors are electrochemical capacitors that have an unusually high
energy density when compared to common capacitors, typically on the
order of thousands of times greater than a high-capacity electrolytic
capacitor. For instance, a typical D-cell sized electrolytic capacitor
will have a capacitance measured in microfarads, while the same size
electric double-layer capacitor would have a capacitance of several
farads, an improvement of about four orders of magnitude in capacitance,
but usually at a lower working voltage. Larger commercial electric
double-layer capacitors have capacities as high as 5,000 farads.
How an Ultracapacitor Works
An ultracapacitor, also known as a double-layer capacitor, polarizes an
electrolytic solution to store energy electrostatically. Though it is an
electrochemical device, no chemical reactions are involved in its energy
storage mechanism. This mechanism is highly reversible, and allows the
ultracapacitor to be charged and discharged hundreds of thousands of
times.
An ultracapacitor can be viewed as two nonreactive porous plates, or
collectors, suspended within an electrolyte, with a voltage potential
applied across the collectors. In an individual ultracapacitor cell, the
applied potential on the positive electrode attracts the negative ions
in the electrolyte, while the potential on the negative electrode
attracts the positive ions. A dielectric separator between the two
electrodes prevents the charge from moving between the two electrodes.
Diagram 2 depicts an ultracapacitor, its modules, and an ultracapacitor
cell.
Schematic of an ultracapacitor module, module schematic, and an
ultracapacitor cell.
Once the ultracapacitor is charged and energy stored, a load (the
vehicle's motor) can use this energy. The amount of energy stored is
very large compared to a standard capacitor because of the enormous
surface area created by the porous carbon electrodes and the small
charge separation (10 angstroms) created by the dielectric separator.
However, it stores a much smaller amount of energy than does a battery.
Since the rates of charge and discharge are determined solely by its
physical properties, the ultracapacitor can release energy much faster
(with more power) than a battery that relies on slow chemical reactions.
Advantage:
The barrier to market has historically been cost. Our initial products
are being designed
to meet specific cost and performance targets established by our
potential customers --
select OEMs that plan to integrate our product in their devices.
Commercial applications:
Low power, specialized applications (e.g., "smart" cards, RFID tags,
remote sensors,
MEMs/NEMs, etc.)
Development status:
The product is in the early development stage. Since we began work on
the technology
we have made much technical progress. A lot of design, testing and
evaluation remains
to be done, however, and we do not have a specific date for production.
We believe that
we are at least 18-24 months away from actual product sales.
In December 2007, Enable IPC and the University agreed to firm up the
license and expand it to grant
exclusivity to Enable IPC for all consumer and industrial applications.
Researchers at the University of Wisconsin have separated
capacitor development into the following categories:
Traditional electrolytic capacitors (first generation) work by
utilizing two conducting plates (usually made of metals that are
capable of being charged) and a thin film dielectric (insulating
material) as a separator. The amount of capacitance that can
be achieved is described in this simple equation:
The first ultra capacitors (also known as "super capacitors") were
probably developed in the late 1950s.;
These came to be known as an Electric Double Layer (or EDL)
capacitor (second generation). They had the ability to store
more energy than standard capacitors but still suffer (in terms
of energy) when compared to batteries. These devices also
employ two conducting plates and a separator. Both plates
have a certain geometric size (thickness and surface area).
However, they are usually made of a conducting carbon which
generally has a much greater surface area than a metal. When
one of the plates is charged, the ions, which compensate for
the charge on the carbon, are stored in the electrical double
layer near the surface of the pores of the carbon. This distance
is on the order of angstroms. Therefore, distance goes way
down in the formula and capacitance goes way up. Now both
pieces of carbon are effectively each capacitors as one is
storing charge with captions and the other with anions.
In a conventional capacitor, energy is stored by the removal of charge
carriers, typically electrons, from one metal plate and depositing them
on another. This charge separation creates a potential between the two
plates, which can be harnessed in an external circuit. The total energy
stored in this fashion is a combination of the number of charges stored
and the potential between the plates. The former is essentially a
function of size and the material properties of the plates, while the
latter is limited by the dielectric breakdown between the plates.
Various materials can be inserted between the plates to allow higher
voltages to be stored, leading to higher energy densities for any given
size.
In contrast with traditional capacitors, electric double-layer
capacitors do not have a conventional dielectric, as such. They are
based on a structure that contains an electrical double layer. In a
double layer, the effective thickness of the "dielectric" is exceedingly
thin—on the order of nanometers—and that, combined with the very large
surface area, is responsible for their extraordinarily high capacitances
in practical sizes.
Pseudo capacitors (third generation) work by EDL means but
also take advantage of oxidation/reduction reactions at an interface.
These oxidation reduction reactions are
like those of batteries. Most pseudo capacitors have been constructed of
two transition metal oxides such as
RuOx, NiOx, etc. (the "x" here is meant to imply that the system can be
either oxidized or reduces). These
oxides are conductive.
The UW / SolRayo / Enable IPC ultra capacitor is a fourth generation
system, combining EDL and an
insulating oxide on top of the carbon. We have some EDL capacity
developed because of the porous carbon
supports as well as the potential that is developed on the insulating
oxide. The difference here is that most of
our charge is stored by the insulating film of nanoparticulate
insulating oxides. Here the charge on the oxide
is developed by a potential determining ion, such as the proton.
In an electrical double layer, each layer by itself is quite conductive,
but the physics at the interface where the layers are effectively in
contact means that no significant current can flow between the layers.
However, the double layer can withstand only a low voltage, which means
that electric double-layer capacitors rated for higher voltages must be
made of matched series-connected individual electric double-layer
capacitors, much like series-connected cells in higher-voltage
batteries.
Ultra capacitor Products
There are three basic market areas where ultra capacitors are used:
consumer electronics, industrial
applications and transportation.
Consumer electronics
Applications in the consumer electronics area include VCRs, CD players,
electronic toys, security systems,
computers, scanners, smoke detectors, microwaves, coffee makers, power
tools and memory backup.
Several companies are targeting future applications, including laptop
and desktop computers (awakening
from sleep mode) and cell phones with added features could require the
use of ultra capacitors.
Industrial
Applications in this area include power supplies, industrial automation
equipment, power transmission and
distribution and wind turbines.
Transportation
Applications in transportation include hybrid automobiles, aircraft door
actuators and rail systems.
By combining Nanoparticles with common carbon sheets in a very
inexpensive process,
researchers have been able to assemble ultra capacitors that -- in the
lab-- have matched
many of the performance specifications of commercial devices.
Commercial applications:
We have an existing agreement with the patent application owners (the
University of
Wisconsin) to exclusively license the product for use in consumer
electronics applications
(which, according to a third party market research firm, represents the
largest market
niche) and industrial markets.
Ultracapacitors, also known as supercapacitors, offer an alternative
source that promises to circumvent the battery scramble and extract
greater efficiency from existing power sources. Because of high price
and manufacturability issues, this electric double layer capacitor (EDLC),
also known as a pseudo capacitor, isn't popular among engineers.
However, it offers boundless growth potential because it responds to key
market and societal needs: It's environmentally friendly, helps conserve
energy, and enhances the performance and portability of consumer
devices. Ultracapacitors also are free from characteristic battery
problems, such as limited cycle life, cold intolerance and critical
charging rates.
Development status:
We are working at the University of Wisconsin to develop α units and ß
units for select
potential customers and we now hope to accomplish this in 2008. We will
keep our
shareholders posted on our progress.
Will ultra capacitors replace batteries?
Batteries utilize a chemical reaction to create power. Ultracapacitors
do not do this; they simply store
electricity and have the ability to charge and discharge very quickly.
In many applications, where charging can
come from another source, they possibly could replace batteries. But
they would not replace batteries where
the power generation is required.
Electric double-layer capacitors have a variety of commercial
applications, notably in "energy smoothing" and momentary-load devices.
Some of the earliest uses were motor startup capacitors for large
engines in tanks and submarines, and as the cost has fallen they have
started to appear on diesel trucks and railroad locomotives. More
recently they have become a topic of some interest in the green energy
world, where their ability to quickly soak up energy makes them
particularly suitable for regenerative braking applications, whereas
batteries have difficulty in this application due to slow charging
times. If the LEES or EEStor devices can be commercialized, they will
make an excellent replacement for batteries in all-electric cars and
plug-in hybrids, as they combine quick charging, temperature stability
and excellent safety properties.
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Ultracapacitor Technology Powers Electronic Circuits
By Youngho Kim, Director of Product Development, NESSCAP Co. Ltd., Korea
As engineering innovations continue to advance ultracapacitors, their
enhanced performance capabilities are expected to hasten the convergence
of batteries and ultracapacitors—strengthening the combination of both
specific energy storage and pulse power design in future applications.
Ultracapacitors are very good at efficiently capturing electricity from
regenerative braking, and can deliver power for acceleration just as
quickly. With no moving parts, they also have a very long lifespan.
An ultra capacitor, also known as a double-layer capacitor, polarizes an
electrolytic solution to store energy electro statically. Though it is
an electrochemical device, no chemical reactions are involved in its
energy storage mechanism. This mechanism is highly reversible, and
allows the ultra capacitor to be charged and discharged hundreds of
thousands of times.
Once the ultra capacitor is charged and energy stored, a load (the
electric vehicle's motor) can use this energy. The amount of energy
stored is very large compared to a standard capacitor because of the
enormous surface area created by the porous carbon electrodes and the
small charge separation created by the dielectric separator.
As the market strives for lighter, more compact wireless and portable
devices with more ingenious features crammed into an ever-tighter space,
a related quest ensues for the next power supply innovation — a
powerful, compact, long-lasting, economical and safe battery. Although
progressing toward this end, current battery technology often
compromises the desired space and weight specifications without properly
satisfying peak power requirements.
Ultracapacitors, also known as supercapacitors, offer an alternative
source that promises to circumvent the battery scramble and extract
greater efficiency from existing power sources. Because of high price
and manufacturability issues, this electric double layer capacitor (EDLC),
also known as a pseudo capacitor, isn't popular among engineers.
However, it offers boundless growth potential because it responds to key
market and societal needs: It's environmentally friendly, helps conserve
energy, and enhances the performance and portability of consumer
devices. Ultracapacitors also are free from characteristic battery
problems, such as limited cycle life, cold intolerance and critical
charging rates.
Why Ultracapacitors?
Ultracapacitors are being developed as an alternative to pulse
batteries. To be an attractive alternative, ultracapacitors must have at
least one order of magnitude higher power and a much longer shelf and
cycle life than batteries. Ultracapacitors have much lower energy
density than batteries, and their low-energy density is, in most cases,
the factor that determines the feasibility of their use in a particular
high-power application.
Available for decades, a conventional electrolytic capacitor is an
energy-storage device that can be compared to a container that gradually
fills with electrical energy and then delivers it when needed in a
sudden burst. Offered just recently, an ultracapacitor is a high-energy
version of a conventional capacitor, holding hundreds of times more
energy per unit volume or mass than the latter by using state-of-the-art
materials and high-tech microscopic manufacturing processes. When fully
charged, these robust devices deliver instant power in an affordable,
compact package.
Long considered an enigma because of price, the advent of inexpensive,
compact ultracapacitors, characterized by an exceptionally high surface
area, excellent conductivity, and superior chemical and physical
stability, herald a new era of practical usage.
A disadvantage of an ultracapacitor is that currently
they store a smaller amount of energy than a battery does.. which makes
them larger. |
