Inward lithium-ion breathing of hierarchically porous silicon anodes
Date Published |
05/2015
|
---|---|
Publication Type | Journal Article
|
Authors | |
---|---|
DOI |
10.1038/ncomms9844
|
Abstract |
Silicon has been identified as a highly promising anode for next-generation lithium-ion batteries (LIBs). The key challenge for Si anodes is large volume change during the lithiation/delithiation cycle that results in chemomechanical degradation and subsequent rapid capacity fading. Here we report a novel fabrication method for hierarchically porous Si nanospheres (hp-SiNSs), which consist of a porous shell and a hollow core. On charge/discharge cycling, the hp-SiNSs accommodate the volume change through reversible inward Li breathing with negligible particle-level outward expansion. Our mechanics analysis revealed that such inward expansion is enabled by the much stiffer lithiated layer than the unlithiated porous layer. LIBs assembled with the hp-SiNSs exhibit high capacity, high power and long cycle life, which is superior to the current commercial Si-based anode materials. The low-cost synthesis approach provides a new avenue for the rational design of hierarchically porous structures with unique materials properties. |
Journal |
Nature Communications
|
Volume |
6
|
Year of Publication |
2015
|
Pagination |
8844
|
Short Title |
Nat Comms
|
Refereed Designation |
Refereed
|
Organizations | |
Research Areas | |
Download citation |