Metal-halide perovskites offer exceptional potential for next-generation photovoltaics, but their long-term stability under realistic operating conditions remains a major challenge. In particular, partial shading of series-connected solar cells and modules can cause high reverse voltages, leading to degradation and potentially catastrophic failure. In this talk, I will present how an understanding of resistive switching in perovskites can be translated into a new device concept that directly addresses this reliability challenge.
I will first discuss the fundamental mechanisms governing resistive switching in perovskite devices. Through detailed device investigations, we show that switching is not mediated by distributed conductive nanofilaments, as commonly assumed, but instead occurs within highly localized regions that form during initial device operation. By introducing a light-assisted patterning approach to precisely define these regions, we eliminate the need for an energy-intensive electroforming step and demonstrate perovskite memristors with low operating voltages, extremely low leakage currents, long data-retention times, and stable operation over millions of switching cycles. These insights provide the basis for exploiting resistive switching as an intrinsic functionality within photovoltaic devices.
Building on this understanding, I will introduce the Memsol concept: a perovskite solar cell with an integrated memristive element that functions simultaneously as a self-regulating protection and bypass mechanism. Under reverse-bias conditions caused by partial shading, the integrated memristor automatically switches to a low-resistance state, protecting the solar cell from degradation. Under normal photovoltaic operation, it returns to a high-resistance state, thereby preserving the solar cell’s performance. Reverse-bias and shading experiments confirm robust and autonomous protection without the need for conventional external bypass components.
Together, these results demonstrate how fundamental insights into ionic and electronic processes in perovskites can be translated into innovative photovoltaic device architectures. The Memsol concept provides a pathway toward intrinsically protected perovskite solar cells and modules and illustrates how multifunctional device concepts can address critical reliability challenges in next-generation photovoltaics.