Large-Scale Spherical Silicon Solar Cell for Advanced Light Management

In order to realize a high power conversion efficiency, a solar cell should effectively utilize most of the incoming photons. Here, we demonstrate a spherical shaped solar cell that is capable of capturing direct, diffuse and background reflected light without the need for a mechanical sun-tracking tool. The spherical cell is based on monocrystalline silicon with an efficiency of 19% ad is developed using a corrugation technique to achieve flexibility in otherwise rigid silicon. The obtained spherical cell is large scale with a diameter of around 4 cm. Theoretical calculations in addition to experimental results confirm the merits of the spherical solar cell which shows an increase in instantaneous power output by 14.8% and 39.7% with respect to a traditional flat cell with the same ground area when sand and white paper are used as reflective background materials, respectively. Finally, the spherical shaped cell shows advantages in terms of lower dust accumulation rate due to its downward orientation.