Three-Dimensional Metal Scaffold Supported Bicontinuous Silicon Battery Anodes
详细信息 查看全文
- 作者：Huigang Zhang ; Paul V. Braun
- 刊名：Nano Letters
- 出版年：2012
- 出版时间：June 13, 2012
- 年：2012
- 卷：12
- 期：6
- 页码：2778-2783
- 全文大小：368K
- 年卷期：v.12,no.6(June 13, 2012)
- ISSN：1530-6992
文摘
Silicon-based lithium ion battery anodes are attracting significant attention because of silicon鈥檚 exceptionally high lithium capacity. However, silicon鈥檚 large volume change during cycling generally leads to anode pulverization unless the silicon is dispersed throughout a matrix in nanoparticulate form. Because pulverization results in a loss of electric connectivity, the reversible capacity of most silicon anodes dramatically decays within a few cycles. Here we report a three-dimensional (3D) bicontinuous silicon anode formed by depositing a layer of silicon on the surface of a colloidal crystal templated porous nickel metal scaffold, which maintains electrical connectivity during cycling due to the scaffold. The porous metal framework serves to both impart electrical conductivity to the anode and accommodate the large volume change of silicon upon lithiation and delithiation. The initial capacity of the bicontinuous silicon anode is 3568 (silicon basis) and 1450 mAh g鈥? (including the metal framework) at 0.05C. After 100 cycles at 0.3C, 85% of the capacity remains. Compared to a foil-supported silicon film, the 3D bicontinuous silicon anode exhibits significantly improved mechanical stability and cycleability.