New solar cells of various shapes

Protection of the environment and the development of renewable resources are major problems related to the national economy and people's livelihood. In particular, more and more attention is being paid to the use of inexhaustible solar energy. Solar cells, devices that could effectively transform solar energy into electrical energy, have attracted much interest in recent years both in academic and industrial circles. The flat silicon solar cells in wide use today are faced with high cost, heavy weight, rigidity and environment problems, and their deformation flexibility is poor. Much research effort has therefore been devoted to improving the fabrication process, including reducing the cost and increasing the flexibility.This article reviews the works published in recent years on the structure characteristics, history, and status of various types of solar cells according to their shapes: rigid flat, flexible flat, mesh-based, and fiber-shaped. Various technical problems and possible solutions are also mentioned. The fiber-shaped solar cells, newly developed in recent years, are described in detail; they are light in weight, bendable, not restricted to flat substrates, and so have wide applications.