Micro-patterned 3D Si electrodes fabricated using an imprinting process for high-performance lithium-ion batteries

To overcome the volumetric expansion of Si used as an anode in lithium-ion batteries (LIBs), we propose 3D Si electrode structures formed on patterned Cu current collectors designed from metal molds fabricated using wire electrical discharge machining (WEDM). The line- and check-patterned Cu current collectors with microscale periods for LIBs are prepared using an imprinting technique with patterned metal molds fabricated using the WEDM process. The line- and check-patterned Si thin-film and powder-type electrodes as anodes are fabricated using radio frequency magnetron sputtering deposition method and conventional slurry casting process, respectively. The morphology of the Si electrodes before and after the cycling process is characterized using optical microscopy and scanning electron microscopy. The electrochemical properties of the Si electrodes are evaluated using a multi-channel battery tester and electrochemical impedance analyzer. In particular, the check-patterned Si electrodes exhibit relatively high-capacity and enhanced cycling performance due to the stress relief of the Si anode.