Integration of a Flexible Thin-Film Lithium-Ion Battery with a Wireless Charging System and a Flexible Micro-LED Array

The development of wearable devices has been significantly hindered by limitations in flexible power solutions. Addressing this challenge, we introduced a novel flexible Li-ion battery, featuring a partitioned cathode and anode film into an electrode array on flexible composite current collectors. This innovative "battlet" design not only exhibits superior electrochemical performance under mechanical stress but also minimizes the package form factor and enhances safety features. Further, we showcased a fully functional wearable device integrating this flexible battery with a wireless charger and a UV microLED array, employing the flexible Fan-Out Wafer-Level Packaging Technology. This comprehensive approach offers a promising avenue for flexible energy storage and charging, poised to revolutionize wearable and biomedical applications by combining high performance, safety, and form factor advantages. Our findings lay the groundwork for future advancements in the integration and optimization of power solutions for wearable technologies.