Flexible Perovskite Solar Cells Perovskite is a crystalline material with the general molecular formula ABX3, in the shape of an octahedron. It is widely used in photovoltaics, LEDs and other fields because of high photoelectric conversion efficiency. Perovskite solar cells (PSCs) are utilized perovskite structural materials as light-absorbing materials, and are representative of the third generation of high-efficiency thin-film cells. Perovskite solar cells, as the current global research and development hotspot, are known as the next-generation energy sources as the lowest-cost photovoltaic cells. Compared with traditional crystalline silicon cells, flexible perovskite solar cells have the following features and advantages: 1. Good soft light performance and good light transmittance. 2. High efficiency. The conversion efficiency of perovskite cells is significantly higher than that of crystalline silicon solar cells. 3. Low cost, it means material cost and production cost. (1).Low material cost. The raw materials are all basic chemical materials, do not contain rare elements, are easy to obtain and have lower purity requirements than silicon materials. In addition, the use of perovskite materials is small, and the total thickness is about 1um. (2).Low production cost. Perovskite solar cells mainly use coating process and PVD process, and the production process is greatly simplified, which is suitable for large-scale production. 4. Flexible perovskites solar cells can be produced in roll-to-roll. It is very light in weight, which can save transportation and labor costs. 5. It can be made into color and translucent films, which can achieve different color effects. 6. The flexible perovskite solar cells can be directly attached to the surface of the building structure, and the installation cost is low. Application Flexible perovskite solar cells (FPSCs) have shown great potential in the field of wearable power supply and integration with architectures in the future due to their advantages of high flexibility, light weight, portability, and compatibility with irregular electronic products. The applications are included BIPV , BAPV, Portable Applications, 3C Applications, Active tag& 5G Communication (Sensor + Photovoltaic), Smart Bus Stations and Billboards, Light Boxes, etc.