...used an oxidised bamboo filament in an oxygen-depleted environment until Edison got hold of it and gave us the expensive, short-lived, and inefficient incandescent using a coiled coil of wire - designed to burn out.
This was followed by the Fluorescent, also modified to give it a lifespan of a few years by the same technology. Without that cheeky little starter plug, and the coils in each end, that tube would outlast its owner - it only needs them because that's how it was designed. To be replaced, for a fee.
So many technologies are returning to their roots and their makers proclaiming themselves clever for it. All I see is a long list of failed technologies and money-spinners that preceded them, that they cant sell any more.
This brilliant idea too, is also very unfortunately destined for the dustbin, or at least modification to make it a repeat-seller unless we change the industry that will provide us with it. Simply because that industry is designed to make as much money as possible, not provide us with cheap and abundant goods, services OR freedoms.
Its a side-effect of capitalism, or of any ism you choose. You want free power? I cant invent it, I'd have to invent free before I can add power to it - and ironically that's the easy part, we're surrounded by free power. What we aren't allowed is the means to get to it.
By the way, Charlie, you could do with proof-reading your article. I'm not one to troll punctuation, but there were a few figments of imaginary English in there...
Cotton that holds a charge — could this be the next big development in flexible batteries?
Flexible devices are already in development, from e-reader screens to bendy laptops. In the world of smart textiles, flexible battery systems are also part of this change — but making the full leap from the solid to fluid has remained out of our scientists’ grasps.
Perhaps not for too much longer. The journal Advanced Materials has reported a new technique, led by the University of South Carolina’s Xiaodong Li, which allows cheap, flexible fabrics to store large amounts of energy.
In the published research report, the experimental subject is a plain, cotton T-shirt. Within the following university release, Li, a professor of mechanical engineering, said:
“We wear fabric every day. One day our cotton T-shirts could have more functions; for example, a flexible energy storage device that could charge your cell phone or your iPad.”
Li developed a process that converts basic, cotton material into “highly conductive and flexible activated carbon textiles.” The fibres in the cotton are altered and made into wires and capacitors capable of storing large amounts of energy — transformed through soaking the material in flouoride and then heated in an oxygen-free environment.
Once the T-shirt was treated, dried and baked, Li’s team found the fibers were converted from cellulose to activated carbon. The oxygen-free environment prevented the material from burning or combusting during the process.
Remaining as flexible as before, by using infrared spectroscopy, the researchers discovered the carbonized material now worked as a repository for electrical current. Testing the material, small swatches were used to function as an electrode, and as a result the fibre worked well as a capacitor.
Termed “activated carbon textile”, Li reports that the material went beyond original predictons; and acts more like double-layer capacitors — also known as supercapacitors — due to the particularly high levels of energy storage possible.
However, this wasn’t enough for the team. The individual fibres were then coated with “nanoflowers” of manganese oxide. Just over a nanometre thick, these thin layers of manganese oxide enhanced the energy-storage capacities of the material even further.
“This created a stable, high-performing supercapacitor,” said Li.
According to the team, even after thousands of test charge-discharge cycles, performance didn’t diminish more than 5 percent. The T-shirts function as a pliable battery, but no longer resemble a normal, white shirt after the process, turning black as one side effect.
However, if these supercapacitors can be stacked up, there may be a future in these kinds of smart textiles - perhaps running out of battery for your smart phone while on the move may end up being a figment of the past.
Li is particularly enthusiastic about improving on the means that carbon fibres are usually created.
“Previous methods used oil or environmentally unfriendly chemicals as starting materials,” he said. “Those processes are complicated and produce harmful side products. Our method is a very inexpensive, green process.”
