Solar batteries, solar panel windows, battery recharging screens, all these key words keep popping up once in a while, bringing up the hopes for a solar revolution, yet that precious invention is still more of a fictional character than a real thing. Or at least that was until some time ago. Back in 2013, when a team of researchers from Kogakuin University first presented their translucent Li-ion battery, no one thought that this invention will see commercial realization, or it will turn into a truly remarkable product.
But the deniers were wrong. In 2015, this same team of researchers, led by Mitsunobu Sato, president of Kogakuin University and professor at the Department of Applied Physics, School of Advanced Engineering, showed their first prototype of a translucent Li-ion battery that can be recharged by the sun. The first transparent solar battery, which turned from a fictional character to a real thing in just two years was showcased at the Innovation Japan 2015 even, which took place in Tokyo on 27-28 August.
The rechargeable solar battery is comprised of the same elements and materials used in regular Li-ion batteries. Two years ago, the team presented the transparent Li-ion battery, which had super thin electrodes- just 80-90 nm, making it transparent and realizng high light transmittance. This year, however, the materials have been changed, so that the translucent Li-ion battery can be recharged by incoming sunlight. The team provided a demo that showed five charge-recharge cycles using near-ultraviolet light.
The prototype is a remarkable innovation that serves as a stepping stone to many more exciting new developments. And although it is still in development stage and it still requires quite a number of tweaks, it did bring light and hope for solar windows, and solar-recharging smartphones and laptops to become a reality sooner than everyone expects.
Image (c) Nikkei Technology