For their 2.25×1.7mm chip-scale flexible lithium-ion battery, they report an energy density of 200mWh/cm3 for a microcell weighing only 236µg. Because the cells are so thin, they withstand a bending radius of 1mm and could conform to the inside curvature of the dental arch when embedded into a dental brace.
The aim is to boost the efficacy of dental braces by combining orthodontics with phototherapy, speeding up the process of bone regeneration for tooth correction, cutting therapy time and overall costs. Advances in panoramic X-ray imaging, intra-oral imaging scanners and biocompatible dental materials now allow the manufacture of personalized dental braces with a better and slimmer fit which could embed near infrared LED arrays for non-invasive oral phototherapy. To date, only bulky external equipment are available, with a programmable controller and an external power supply or battery. Often limiting battery integration is their form factor, due to a rigid encapsulation ensuring proper insulation from corrosive toxic materials.