| 초록 |
Flexible batteries that can tolerate large mechanical stress are of considerable interest in portable electronics. However, most designs employ thin film batteries, which are not practical because of their low energy capacity and structural limitations of the sheet-like architecture. Here we report a cable-type structure for lithium-ion batteries with exceptional mechanical flexibility. The batteries comprise several anode strands coiled into a hollow-spiral core, which is surrounded by a heat-resistive separator wetted with liquid electrolyte and a tubular outer cathode, and finally enclosed in a heat-shrinkable packaging tube. The multi-helical anode structure is critical to the robustness under mechanical stress and facilitates electrolyte wetting of battery components. A prototype showed stable discharge characteristics regardless of bending strain and successfully powered an LED screen and MP3 player under severe twisting and bending. The proposed battery design will free product designers from conventional constraints and might facilitate breakthroughs in flexible and wearable electronics. |
