3D-Printing Water-Soluble Channels Filled with Liquid Metal for Recyclable and Cuttable Wireless Power Sheet
This enables recyclable and durable wireless power sheets for IoT and ambient computing applications, though it is incremental in improving existing WPT technology.
The paper tackled the problem of conventional 2D wireless power transfer systems losing functionality when damaged, by proposing a recyclable and cuttable sheet using H-tree wiring and water-soluble channels filled with liquid metal, achieving a Q-factor over 55 at 6.78 MHz and recovering 98% of the liquid metal after four cycles.
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.