thin-film Li-ion microbatteries for autonomous

Abstract—Autonomous MEMS require similarly miniatur-ized power sources. In this paper, we present the first working three-dimensional (3-D) rechargeable Li-ion thin-film microbat-tery technology that is compatible with MEMS requirements. The technology has been developed, and full 3-D cells have been manufactured on both glass and silicon substrates. Our 3-D mi-crobatteries have a sandwich-like structure of conformal thin-film electrodes, electrolyte and current collectors. The films are de-posited sequentially on all available surfaces of a perforated substrate (e.g., silicon or a glass microchannel plate or “MCP”) using wet chemistry. The substrate has thousands of high-aspect ratio holes per square cm, thereby providing more than an order of magnitude increase in surface area per given footprint (original 2-D substrate area). The full 3-D cell consists of a Ni cathode current collector, aMo