Scalable synthesis of ant-nest-like bulk porous silicon for high-performance lithium-ion battery anodes

• Published in: Nature communications 2019-03, Vol.10 (1), p.1447-1447, Article 1447
• Main Authors: An, Weili, Gao, Biao, Mei, Shixiong, Xiang, Ben, Fu, Jijiang, Wang, Lei, Zhang, Qiaobao, Chu, Paul K., Huo, Kaifu
• Format: Article
• Language: English
• Subjects: 140/133; 140/146; 147/135; 147/143; 639/301/299; 639/4077/4079; 639/925/357/551; Anodes; Anodic coatings; Chemical synthesis; Electrode materials; Electrodes; Flux density; Humanities and Social Sciences; Lithium; Lithium-ion batteries; Magnesium; multidisciplinary; Porosity; Porous silicon; Rechargeable batteries; Retention; Science; Science (multidisciplinary); Silicon; Silicon base alloys; Swelling
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-019-09510-5

Although silicon is a promising anode material for lithium-ion batteries, scalable synthesis of silicon anodes with good cyclability and low electrode swelling remains a significant challenge. Herein, we report a scalable top-down technique to produce ant-nest-like porous silicon from magnesium-silicon alloy. The ant-nest-like porous silicon comprising three-dimensional interconnected silicon nanoligaments and bicontinuous nanopores can prevent pulverization and accommodate volume expansion during cycling resulting in negligible particle-level outward expansion. The carbon-coated porous silicon anode delivers a high capacity of 1,271 mAh g −1 at 2,100 mA g −1 with 90% capacity retention after 1,000 cycles and has a low electrode swelling of 17.8% at a high areal capacity of 5.1 mAh cm −2 . The full cell with the prelithiated silicon anode and Li(Ni 1/3 Co 1/3 Mn 1/3 )O 2 cathode boasts a high energy density of 502 Wh Kg −1 and 84% capacity retention after 400 cycles. This work provides insights into the rational design of alloy anodes for high-energy batteries. Silicon is a promising anode material for lithium-ion batteries but experiences large volume changes during cycling. Here the authors report a scalable method to synthesize porous ant-nest-like silicons. The unique structure of this anode solves the swelling problem and enables impressive performance.