A flexible self-charged power panel is integrally designed and fabricated to simultaneously harvest solar and mechanical energy and convert and store in electric energy. The flexible amorphous silicon solar cell, the transparent triboelectric nanogenerator (TENG), and lithium (Li)-ion batteries are coherently integrated into one thin panel with the encapsulating materials, ethylene-tetra-fluoro-ethylene (ETFE) for the solar modules. The flexible self-charged power panel exhibits good performance to directly convert solar and mechanical energy into electricity that was directly stored in Li-ion battery without excessive energy loss. The integrated device also greatly minimizes the usage of current collectors, substrates and packaging materials. Moreover, such a power panel can compensate for the absence of solar cells and prolongs the time of energy supply and improve the energy density of the whole device.