The PV cell manufacturer Q-Cells SE, based in Germany, has notched up what is beleived to be a new world record for polycrystalline solar cell efficiency after testing of a high-performance cell based on its new Q.ANTUM concept. The independent calibration laboratory Fraunhofer ISE (Institute for Solar Energy Systems) in Freiburg confirmed the new efficiency rating of 19.5% measured on a cell of area 243 sq cm, open circuit voltage 652 mV and short-circuit current density 39.0 mA/sq cm. ‘We have already managed to significantly improve the cell efficiency rating thanks to our new cell concept Q.ANTUM, and we will further optimise this technology to achieve efficiencies of more than 20%,’ said Peter Waver, the company’s senior vp for technology.

In the company’s research centre at its Thalheim site in Germany, a polycrystalline, 180 µm thick silicon wafer was metallised and passivated with functional nanolayers on the reverse side. This new type of structure for the reverse side, consisting of dielectric layers combined with local contacts, improves the solar cell’s optical and electrical characteristics and significantly boosts output as compared to the previous standard technology, which uses a completely aluminum-metallised back structure.

At the beginning of 2011 Q-Cells broke the same world record, achieving a cell efficiency rating of 18.45% with their design. The European Solar Test Installation (ESTI) confirmed a total module output of 268 W and a module efficiency rating of 17.84% at the aperture area.

The innovative cell structure is said to be suitable for a range of silicon qualities and for very thin wafers, which suggests a potential for further cost savings in the industrial production of solar cells.

The state of Sachsony-Anhalt and the German federal government, among others, provided funds for the development. Some development was carried out as part of the top cluster Solarvalley Central Germany framework.