Mihai Duduta1 Sebastien de Rivaz1 David Clarke1 Robert Wood1

1, Harvard University, Cambridge, Massachusetts, United States

Existing fabrication technologies cannot be used to make lightweight, high power density lithium ion batteries (>300mg). The need is increasing for these small, powerful batteries, as advances in fabrication techniques push the limits of miniaturization in robotics, haptics, wearable and biomedical technologies, and mobile computing for the Internet of Things. Unfortunately, current fabrication methods for lithium ion cells force the end user to make a choice between high energy density and lightweight batteries. Supercapacitors can provide even higher power density (>10 kW/kg), but have very short discharge times (0.1- 5s) which limits the range of potential applications. To push the limits of performance, we have developed a hybrid manufacturing approach which uses commercially available lithium ion materials and a laser micro machining method to build lightweight (10-200 mg) high power density (>1 kW/kg) batteries.