Recent advance in new-generation integrated devices for energy harvesting and storage

Energy harvesting and storage devices, including lithium-ion batteries (LIBs), supercapacitors (SCs), nanogenerators (NGs), biofuel cells (BFCs), photodetectors (PDs), and solar cells, play a vital role in human daily life due to the possibility of replacing conventional energy from fossil fuels. However, these isolated devices only have limited performance and/or sole applicability, and cannot provide enough energy for application with long-term run and the ever-changing working positions. This suggests that it is urgent to develop the fine self-powered systems to meet the growing demand of energy for long-term use in different environment scenes. Developing integrated power pack, combining energy harvesting and storage, is an effective path to obtain a small size, light weight, high density and high reliability energy system. In this review, eight types of multifunctional integrated devices, such as LIB&SC, LIB&NG, BFC&NG, PD&BFC, SC&PD, SC&solar cells, NG&SC&solar cell, and LIB&solar cells, for energy harvesting and storage are reviewed in a broad sense, and a comprehensive summary of the recent development trends and highlights in the integrated device fields is given. Finally, the challenges and future outlooks for their successful commercialization are featured based on the recent advances and important findings.