The Fraunhofer Institute for Solar Energy Systems ISE has set a new efficiency record for silicon solar cells. For the first time, an efficiency of 25.1 percent has been measured for a both sides-contacted silicon solar cell. Having a simple rear side contact without any patterning, this type of solar cell converts one quarter of the incident sunlight into electricity. The new concept for the solar cell rear side holds great potential for further increases in efficiency.
This record achieved by Fraunhofer ISE is the highest efficiency achieved to date for both sides-contacted silicon solar cells, characterized by having metal contacts on both the front and rear sides. This solar cell at 25.1 percent efficiency features a novel concept, namely a full-area passivated back contact. “To improve the solar cell efficiency, the focus has been on increasingly complex solar cell structures up to now,” explains Dr. Martin Hermle, Head of the High Efficiency Solar Cells department at Fraunhofer ISE. “The biggest advantage of our new concept is that we can now contact the entire rear cell surface without patterning. Compared to the high-efficiency solar cell structures presently in use, we offer both a simplified manufacturing process and higher efficiencies at the same time,” says Hermle.
