Determining the shunt resistance of individual subcell in Tandem Perovskite solar cells

Tandem solar cells can be described as two solar cells electrically connected in series. Thus, given that the two subcells share the same current, the consequence output current is limited by the subcell delivering the lower current. If one of the subcells strongly underperforms, the global efficiency of the tandem devices is compromised. In this paper, the limiting properties of the underperforming subcell is exploited to extract its shunt resistance. An analytical approach to evaluate open circuit voltage and shunt resistance of each subcell is presented in the work. A numerical model, built in Sentaurus TCAD, able to describe I-V characteristic of a tandem solar cell is also performed in this work.