IBM ups efficiency 40 percent for low-cost solar cell formulation

Thin-film solar cells hold the promise of a cheap, renewable energy source that could make fossil fuels obsolete, but thus far the cells’ reliance on rare elements and expensive vacuum deposition manufacturing has impeded their progress. IBM Research has proposed solutions to both stumbling blocks by demonstrating a photovoltaic cell that uses common, abundant elements and is produced using an inexpensive nanoparticle- and spin-coat-based “printing” technique.

With 9.6 percent efficiency, the so-called kesterite solar cell beats the previous efficiency record of 6.8 percent for similar structures, bringing kesterite closer to the efficiency of established solar cell formulations, IBM said.

IBM plans to optimize the architecture further, in hopes of raising its efficiency above 11 percent in order to beat both CIGS and CdTe formulations. The team will also experiment with alternative to spin coating, such as dip coating, spray coating and slit casting.