Authors: Haiping Jia, Xiaolin Li, Junhua Song, Xin Zhang, Langli Luo, Yang He, Binsong Li, Yun Cai, Shenyang Hu, Xingcheng Xiao, Chongmin Wang, Kevin M. Rosso, Ran Yi, Rajankumar Patel, Ji-Guang Zhang
Published: 2020-03-19
DOI: 10.1038/s41467-020-15217-9
Source: Full article
AbstractPorous structured silicon has been regarded as a promising candidate to overcome pulverization of silicon-based anodes. However, poor mechanical strength of these porous particles has limited their volumetric energy density towards practical applications. Here we design and synthesize hierarchical carbon-nanotube@silicon@carbon microspheres with both high porosity and extraordinary mechanical strength (>200 MPa) and a low apparent particle expansion of ~40% upon full lithiation. The composite electrodes of carbon-nanotube@silicon@carbon-graphite with a practical loading (3 mAh cm−2) deliver ~750 mAh g−1 specific capacity, <20% initial swelling at 100% state-of-charge, and ~92% capacity retention over 500 cycles. Calendered electrodes achieve ~980 mAh cm−3 volumetric capacity density and <50% end-of-life swell after 120 cycles. Full cells with LiNi1/3Mn1/3Co1/3O2 cathodes demonstrate >92% capacity retention over 500 cycles. This work is a leap in silicon anode development and provides insights into the design of electrode materials for other batteries.