3D-Printing Water-Soluble Channels Filled with Liquid Metal for Recyclable and Cuttable Wireless Power Sheet
2026-04-10 • Human-Computer Interaction
Human-Computer Interaction
AI summaryⓘ
The authors made a special wireless power transfer sheet that can still work even if you cut it or bend it. They used a tree-like wiring design and filled water-soluble channels with liquid metal to make the sheet reusable. When the sheet is cut, the remaining parts still function, and the liquid metal can be recovered by dissolving the channels in water. The sheet was tested to be strong, flexible, and efficient at transferring power, and it can be recycled multiple times with minimal loss. This technology could help power everyday devices reliably over a long time.
wireless power transferH-tree wiringliquid metalpolyvinyl alcoholQ-factorbendabilityrecyclabilityIoTambient computing3D printing
Authors
Takashi Sato, Ryo Takahashi, Kento Yamagishi, Takao Someya, Michinao Hashimoto, Eiji Iwase, Yoshihiro Kawahara, Junya Kurumida, Wataru Iwasaki
Abstract
A recyclable and cuttable wireless power transfer (WPT) sheet is proposed, enabled by H-tree wiring and water-soluble channels filled with liquid metal (LM). Conventional 2D WPT systems lose their functionality when physically damaged or modified. The H-tree wiring pattern maintains the operation of the remaining coils even after the outer region of the sheet is cut away. The LM can be recovered by dissolving 3D-printed polyvinyl alcohol (PVA) channels in water. The sheet dimensions were experimentally optimized, and a Q-factor over 55 was achieved at 6.78 MHz. The sheet maintained its bending stiffness and electrical resistance during 100 bending cycles. After four dissolution-refabrication cycles, 98 percent of the LM was recovered with stable electrical properties. The WPT sheet can be integrated into everyday objects and enables long-term, continuous operation of surrounding electronic devices, contributing to IoT applications and ambient computing.