Our needs for portable power keep growing. Electrical and electronic devices
are great, and the features and functionality they provide continues to expand.
But none of these devices are worth anything without the power to make them work.
In addition to some of the other new battery technologies we've recently
featured, there are some portable power generation methods. First, nano-engines could generate electricity efficiently from small amounts of fuel. And second, small fuel cells can producing power from hydrogen gas. Both of these use some kind of
fuel (hydrogen, alcohol, or hydrocarbon in liquid or gas form) to run the
system and generate electric power.
The miniature engine is the project of a group of researchers at MIT. They recently
announced that they have fabricated all the components necessary to
produce micro scale gas-turbine engine that could provide 10 times longer life
than a comparable weight of batteries (storage per kilogram.)
Creating these micro-turbines uses the same etching technology used to create computer chips. While the individual components have
been developed, the next step is to get all of the components working together
to demonstrate the abilities and effectiveness of the device.
Simultaneously, development is continuing on
micro fuel cells as another promising avenue of development. Like larger
scale fuel cells being developed for automotive use, these systems produce
electricity directly when fuel is supplied to a catalyst. There are already some fuel-cell projects in the works, including cell phone chargers, and portable lights.
The move from power storage to power generation could be a powerful shift for portable electronics as well as for the automotive industry. Creating fuel-powered electric cars might seem like a step backward, but not when the fuel is hydrogen, and the power per kilogram is so very high.
Lithium ion batteries are great. They've taken us miles beyond
traditional non-rechargeable batteries. But, and you might have heard
about this, they sometimes explode. They're also reaching the limit of
their capacity per kilogram. One hundred fifty watt-hours per kilogram
is a great number for a Li-Ion battery, but in the tech world,
everything needs to double every few years, and if we're not going to
do it with Li-ion batteries, we need to find something new.
And thin film batteries are certainly something new. The batteries are
actually composed of flat layers of pure lithium electrodes and an
electrolyte bonded to a glassy surface. The batteries never lose
charge, can withstand extremes of heat and cold, can charge quickly and
discharge slowly or quickly an infinite number of times, can pack a ton of power into a small
space, and will not explode in your lap if you dent them.
Increasing the power to kilogram ratio is extremely important, not just
in mobile computing, but also for electric driving, where the weight of
batteries is a huge problem. Lighter electric batteries
means less electricity is needed to power the car, and so the car can
go further, faster, and weigh less.
Thin film batteries are, of course, currently far to expensive for
retail. But if Silicon Valley has taught us anything, it's that a
technology in demand never stays expensive for too long.
Bateries are electrochemical cells that have an ion gradient between
two chemical compounds. Capacitors are two pieces of metal placed very
close to one another so that a charge can store up between them.
Capacitors charge and discharge extremely quickly. Batteries are slow
to re-charge, if they re-charge at all, but can discharge slowly and
under control. Capacitors can hold a large amount of power per square
inch, batteries cannot. Capacitors are usually made of environmentally
benign substances, batteries usually are not.
By combining the quick-charge and large storage capability of a
capacitor, with the slow controlled discharge of a battery, we could
have an entirely new class of battery that is much more environmentally
sound. That's what researchers at Brown University say they've done.
It's no simple matter, I won't try to explain it (head to physorg
for more info,) but I can explain the effect it would have
on consumer electronics. Smaller batteries, extremely rapid charge
time, and, get this, it's flexible and about the thickness of an
overhead transparency. No more poisonous power packs that occasionally
explode. No more overnight charging and "CRAP I forgot to charge my
cell phone!" moments.
There are some obstacles still to overcome, the capatery holds less and
less charge each time it is re-charged. But it's a new technology, and
there will be hundreds of solutions to each problem they encounter. I
expect one to be in my ultra-slim phone within the decade.
The Millennium Prize
is given out every two years and is, basically, technology's equivalent of the Nobel. Professor
Shuji Nakamura was awarded the 1m euro prize for his invention of
white, blue, and green LEDs as well has his invention of the blue laser
diode. LEDs, if you haven't been paying attention, promise to provide
a low-cost, highly efficient and non-toxic alternative to Edison's light bulb.
Eschewing traditional Japanese modesty, Nakamura
said, "I hope the award of this prize will help
people to understand that this invention makes it possible to improve
quality of life for many millions of people." He refers here to the
ability of blue LEDs to sterilize water efficiently and also to solar
powered lighting initiatives to which he has pledged to donate part of
his award money.
As an example of how big a deal LEDs (and Nakamura's works) are, the
only other Millennium prize ever was given to Tim Berners-Lee, who
invented the Internet.