Ultra‐Lightweight, High Power Density Lithium‐Ion Batteries

Current fabrication methods for lithium‐ion batteries impose a limit on how light a high power battery can be made. The lack of lightweight (<300 mg), high power batteries is a significant constraint to the development of untethered micro‐robots, wearable haptics, mobile computing, and biomedical applications. We have developed a laser micro‐machining and assembly process which can produce batteries up to 30 times lighter than the lightest high power commercial cell, at comparable power densities (>1 kW/kg). Our process is versatile and can be adapted to make custom geometries, miniature high voltage cells, and more, all while using a broad range of starting materials. We see this technology as a path to highly versatile miniature power sources, that will enable a wide range of small‐scale applications.