High-performance all-solid-state thin-film lithium microbatteries based on wet-chemistry-prepared 3D CuO electrodes

3D electrode design is proposed as an attractive approach to simultaneously increasing energy and power densities for all-solid-state thin film lithium microbatteries (TFBs). However, currently reported TFBs based on 3D electrodes prepared by atomic layer deposition or physical vapor deposition suffer from relatively low areal capacity and high fabrication cost. In this work, a 3D CuO nanowire array electrode with controllable thickness is directly prepared on a conductive substrate by a facile wet chemistry route, based on which a high-performance CuO/LiPON/Li TFB is efficiently constructed. Possessing abundant electrode/electrolyte interface contact, shortened ion diffusion length, and accommodation capability for volume change, the CuO/LiPON/Li TFB exhibits a large areal capacity (92 μAh cm −2 at 15 μA cm −2 ), high rate capability (11 μAh cm −2 at 960 μA cm −2 ), and good cycle performance (nearly no capacity loss after 70 cycles). This work establishes the great potential of preparing 3D electrodes by wet chemistry routes for realizing high-performance TFBs. Graphical Abstract