Scientists at the Massachusetts Institute of Technology are developing new long-lasting power cells that they say will be capable of charging to full power in a matter of seconds.

Using nanotechnology, MIT's Professor Joel E. Schindall has laid the groundwork for what he calls a "synthetic battery," a power cell that, instead of the chemical reactions used in standard units, stores charge in a forest of tiny carbon "nanotubes."

Elsewhere, some innovators are experimenting with devices that draw power from the human body's kinetic energy. Such technology is already used to power watches, but scaling this up to the level required by smartphones is difficult.

But one team from the Georgia Institute of Technology have created a new technique that uses bodily movement, such as footfalls, to generate static electricity that can then be harnessed in quantities that could viably charge larger devices.

Such solutions are clearly some way off commercial development, but with Apple rumored to be designing its hotly-anticipated iWatch around a power source based on kinetic and solar power, a battery-free world isn't such a distant dream.