NREL's Cell and Module Performance group's asymptotic Pmax protocol for perovskite devices

Perovskite photovoltaic devices have demonstrated a very rapid rise in reported efficiencies. Potentially extreme artifacts which tend to manifest themselves as large hysteresis effects, depending an scan rates and directions and light bias exposure history are often seen. This can make characterization difficult and may have resulted in some exaggerated efficiency reports. NREL's Cell and Module Performance (CMP) group's approach to standardized measurements of perovskites is discussed.