A transparent battery could replace the glass windows of the houses.
The newly developed clear batteries still have a low power level, but may already add autonomy to the batteries of the Smart glass (like the outgoing Apple one) or electric cars.
Most battery research focuses on increasing power or energy density - that is, how much energy can be stored in a given volume.
Hironobu Minowa and his colleagues at the Japanese communications giant NTT thought instead of focusing on making a battery as inconspicuous as possible.
The team created new versions of all battery components to reduce light absorption and reflection. The result is a transparent battery the size of an A4 sheet of paper - it looks just like glass.
The capacity of the transparent battery still has very little capacity, one thousandth of conventional batteries: 1 milliampere (mAh) against more than 1000. On the other hand, it lets 69% of the light through.
The transparent battery capacity is enough, however, to power an LED or digital clock, says Minowa. And since its creation, in just 11 months it has already doubled its capacity and tripled its transparency: we can well hope.
A hand to the internet of things
The more homes are filled with sensors and devices (to optimize lights, temperature and any other aspect), the more this transparent battery technology can help clean up plugs and cables everywhere.
Transparent batteries, the limits to be overcome
Currently the team has not been able to make transparent batteries wider than an A4 sheet, but obviously already now it is possible to put various panels together to cover larger surfaces.
However, such transparent batteries will be very useful for all devices that need the two key factors: energy and transparency.