The Device Itself is the Battery
Researchers at the Imperial College in
London are also working on flexible battery prototypes. Their approach is
fascinating: the casing of a smartphone, notebook or tablet itself becomes the
battery. Electric vehicles would also be an exciting application field.
"The car of the future would be able to receive its energy from the roof,
the engine hood or the door, thanks to our composite material" explains
project coordinator Dr. Emile Greenhalgh.
The researchers would also be able to
increase the range of cars by about 130km in combination with conventional
batteries. That would be double the performance of the latest electric cars
which normally only go up to 150km in one charge. With the new technology, it
would be possible to have smaller and simpler cars for city traffic, where one
could easily afford to operate a normal battery for short distances.
Super condensors are the basis of the
research project as they have a higher capacity compared to normal condensers;
and in comparison to batteries, can emit more energy in short bursts, for
example while accelerating a vehicle. Researchers are using carbon fiber as an
electrode material. The electrolyte is a polymer gel and its isolator is glass
fiber. The major advantage is that battery behaves like normal carbon and can
be used in the exact same way. As of now there are already a couple of
prototypes, but the researchers cannot predict when the material will be
released in the market.
A Full Car Battery in Five Minutes
For vehicles, an interesting new type of
battery called Redox Flow is being researched in Pfinztal at the Fraunhof
Institute for Chemical Technology (ICT). The idea is to be able to charge not
only small batteries but any large ones just as quickly. This is not possible
with conventional batteries: if you want to charge big batteries in a short time,
the charging station requires a lot of energy. On the other hand, the battery
would overheat without a cooling system.
The Redox Flow battery is a type of mixture
of a fuel cell and an accumulator. A car designed using this technology can be
charged in 5 to 10 minutes, but with an energy density that is lower than that
of a lithium ion battery. The trick to charge quickly lies in the fluid
electrolytes that are stored in two tanks. A pump rinses the electrolyte in the
converter cell, and ions in both liquids are exchanged through the membrane. If
the electrolyte does not generate any more energy, the tanks can be simply by
evacuated and refilled eye. A human hair, with its 100,000 nanometer width, is
gigantic in comparison.
The anode of this battery is made from
nickel and tin and the cathode from polyanilin. A gel-type polyethylene oxide
(PEO) is used as a conductor that also insulates nano wires. Aluminum and
copper are put in wires to close the current circulation. At the moment,
researchers are working on the stability of the battery because even the latest
versions diminish in energy capacity after roughly 20 charging cycles.
Transparent Batteries for New Devices
Batteries are not
only performing better, but are also getting smaller and more flexible.
Researchers have been doing work even on their visual appearance. As a rule,
today's ugly batteries disappear somewhere inside the chasses of devices, which
is fine because the devices are not transparent. However prototypes of
transparent displays are already being researched and researchers are also
working on transparent tablets that can curl up like a newspaper. A research
team of the SLAC National Accelerator Laboratory at Stanford University in
California has manufactured the first transparent lithium ion battery, so that
the user does not have to stare at a battery block. As none of the existing
materials can be made transparent nor are transparent alternatives available,
the designers are trying to reinvent the battery and make its elements smaller.
For the electrodes, a latticed framework was developed for which every rod is
only 35 micrometers long "Something smaller than 50 micrometers is not
visible to the naked eye" explains researcher Yuan Yung. The base material
is PDMS (Polydimethylsiloxane), a silicone that is used among other things in
cosmetic products. According to the researchers, the battery should be close to
60 percent transparent and very flexible, even when layers are placed over one
another to increase the capacity. This is necessary because at the moment, the
concept battery has only half the power of a lithium ion battery. Although the
manufacturing process is complicated, the costs should not be much higher than
that of today's lithium ion batteries.
Wi-Fi Upgrades Prolong Battery Life
Researchers are not only working on
batteries but also on energy-efficient technologies. One of the large energy
consumers in mobile devices is Wi-Fi, for which Duke University in Durham, USA
has found a solution which could as much as double a device's battery capacity.
Especially in networks with many users, the connection consumes a lot of energy
as the devices compete with each other for data transfer, and that too for
prolonged periods. "SleepWell" technology developed at the university
helps manage the devices' communications not only with the router but also
amongst each other. The clients observe whether or not another device is
loading data: if that is the case, the client takes a break. The data is
distributed in small packets so that the transfer capacity splits up equally.
The process helps only in networks which are used frequently—someone who does
not use Wi-Fi much does not benefit from it.
As "SleepWell" does not require
any change in Wi-Fi standards, the technology can be integrated in all devices
immediately via a simple firmware upgrade. The developers hope to demonstrate
these capabilities to device manufacturers as soon as the test phase is
completed.
Longer Performance Through Normal Usage
A larger application field offers a
technology is one which aims to help the battery charge when keys on the
keyboaii of a notebook or the touch screen of a tablet are pressed. The faster
and more frequently the user taps at his device, the faster the battery could
charge. What sounds like a paradox should soon become a reality thanks to a
pressure-sensitive sheet. The idea is that when a user types a text on his/her
notebook, the released kinetic energy while typing should generate small
amounts of electricity for the battery. This piezoelectric effect develops when
crystals like quartz are formed —at least in theory. The practical
implementation in of such a technique is not easy at all. Researchers at the
Royal Melbourne Institute of Technology (RMIT) in Australia have succeeded in
measuring the pressure and voltage arising out of normal typing activity in
field of 10 to 100 nanometers. For comparison, a blood corpuscle is about 8,400
nanometers.
The electricity produced by pressing keys
could increase the life of a charged battery by up to 10 percent. The
researchers want to accommodate such sheets in mobile devices but also in
medical applications. Pacemakers, for example, could be charged solely by
harnessing the patient's blood pressure.
Taste of the Future
Industry veterans and researchers are
working intensively on solutions to the battery problem. This is, after all,
the weakest and oldest technology inside many of our gadgets. Everything is
shrinking today, but batteries are in fact becoming disproportionate large.
When even a single one of these techniques it is good for mass production and
adoption, mobile technology will be much more free and easy—without the
annoying need to search for another power point!
