Uniform Li Deposition Formed by Lithophilic SiO2 Dopped Porous 3D Carbon Host for High Energy Density Li Metal Anode
Sara Hamed
Aalto University
The SiO2/CNT composite coated on carbon paper (CP) have been rationally designed as materials for Li metal anodes through a magnesiothermic reduction of silica. The SiO2 particles afford a critical effect compared to previous Li metal “host” frameworks. They serve as nucleation seeds for metallic Li deposition. This suppresses Li deposition outside the framework and facilitates better protection of Li deposited into the “host”. While the CNTs could ensure a rapid electron transport in conductive networks and facilitate the Li+ diffusion through accessible electrolyte infiltration, SiO2 particles would efficiently transfer lithophobic CNTs to a lithophilic. In the well-designed SiO2/CNT@CP host, the dendrite formation is effectively suppressed. As a result, the SiO2/CNT@CP host delivers a favorable CE of above 99.99%, a low hysteresis voltage (∼40 mV) and smooth voltage profiles after continuous plating/stripping for more than 1250 h at 1 mA cm–2.
