Light-permeable, photoluminescent microbatteries embedded in the color filter of a screen

The battery and the screen are the two components occupying the largest volume in many electronic devices. Integrating them together will eventually engender a great reduction of device size. The current study demonstrates a promising strategy towards ultimate-compact electronic devices. Herein, a photoluminescent microbattery with reasonable light-permeability and hazing ability is developed. This aqueous Zn-MnO_x/polypyrrole based microbattery features a flat architecture with interdigitated electrodes and utilizes a photoluminescent gelatin based electrolyte by embedding colloidal CdTe quantum dots. Furthermore, borax is introduced into the electrolyte as an additive, which effectively prevents luminescence quenching of the quantum dots and simultaneously enhances the electrochemical performance of the microbattery. A high device energy density of 21 mW h cm^-3 is obtained. One step further, a three-primary-color (red-green-blue, RGB) photoluminescent microbattery array is assembled, endowing the battery with the function of a color filter and realizing a battery-in-screen configuration.