Friday, January 25, 2013

Super Capacitors and Super Batteries

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New Hopeful
in the Hunt for a
Safe Super Battery

Boeing Dream-Liner Burned-out Battery

I have written fairly extensively over the years about the universal world need for a quantum leap in battery design. The recenty reported battery electrical problems that grounded the entire stock of Boeing's Dreamliner has again brought into sharp focus the urgent need for safer, lighter, and higher-capacity batteries.

BATTERIES

Batteries are essentially CHEMICAL FACTORIES. Electricity is both stored and retrieved by changing the chemistry of the substances inside the battery. These chemical reactions cause the release of both heat and gasses. As Boeing have to their great expense now fully realised, heat and gasses are very much not wanted in an enclosed space.

Another disadvantage to batteries is that they take a long time to charge up, and cannot release the charge very quickly either. If you try to charge or discharge a battery too quickly - they go on fire or blow up, as Boeing are only too painfully aware.

The reason the all-electric car has not taken off is because the batteries are:

(1) Way too expensive.
(2) Don't hold enough electricity for long journeys.
(3) Take WAY too long to charge.
(4) Are too bulky and heavy.
(5) Are too Short lived - a few years - where a capacitor could out-live the car twice over.
(6) Are prone to overheat or blow up.

CAPACITORS

By contrast, capacitors, to date, have only TWO of the above disadvantages - bulk and weight, and charge capacity.

The other way to store electricity is by the use of a CAPACITOR. A capacitor stores energy in a very different way to a battery. It is a charge device - meaning it does not generate ANY chemical reactions, heat or gasses. This is a huge advantage.

The problem with capacitor storage has been the charge capacity to size/weight ratio. In other words, you needed tens if not hundreds of times more space and or weight to hold the same amount of electrical charge.

In recent years nano technology has made great advances in the development of Super Capacitors. But till now they still need to be too large for many uses, for instance, as a main power source in electric cars.

FAILED PROMISES

In posts to this blog ranged over years, I have outline some of the many hopeful contenders in the race for a better battery. To date all have failed to produce the holy grail of energy storage, and many would appear to be no more than "vapour ware".

There are lots of hopefuls out there ferreting away trying to develop viable batteries but nothing much has actually been delivered in more than 5 years of development.



THE NEW HOPE

Now on the horizon appears a new hopeful, it is based on a cheap, natural, safe, non toxic, and plentiful substance. The form of this substance was only discovered some five years ago.

Graphene, a form of carbon, is what I speak of. The above picture is the form of graphine first produced using almost a school boy low tech method of Scotch Tape to peel and peel and peel layer after layer of graphite to arrive at the all important single layer.


Graphene is a matrix of carbon atoms in a single layer - looking something like chicken wire. It has some truly amazing properties, one of these properties may lend it to the development of a compact and efficient Ultra-Capacitor. Developers have come up with new ways of producing graphene in usable quantities.

STORAGE CAPACITY DEMONSTRATED

Graphine is known to have amazing electrical properties. A tiny but viable capacitor has been demonstrated that can hold electrical charge many many times greater than anything previously demonstrated in a capacitor.

Now the development chase is on full-speed - to learn to produce industrial quantities of graphene and turn it into amazingly high capacity capacitors.

Mobile phones that would charge in seconds and last a week, electric cars that could re-charge in 10 minutes and travel 300 - 400 miles before re-charging. We will hopefully wait and see.

This - at last - is looking hopeful.


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