To
conquer inherently low conductivity, volume swelling, and labile solid electrolyte interphase (SEI) films of
Si anode in lithium ion battery (LIBs), it is widely accepted that
appropriate structure design of Si-C hybrids performs
effectively, especially for
nanosize Si particles.
Herein, inspired by the sturdy construction of high-rise buildings, a
mansion-like 3D structured
Si@SiO
2/PBC/RGO
(SSPBG) with separated rooms is developed based on 0D core-shell Si@SiO
2,
1D
pyrolytic bacterial cellulose (PBC) and 2D reduced graphene oxide (RGO).
Therefore, these hierarchical protectors operate
synergistically to inhibit the inevitable volume changes during electrochemical
process. Specifically, tightly coated SiO
2shell as the first
protective layer could buffer the volume expansion and reduce detrimental
pulverization of Si NPs. Furthermore, flexible spring-like PBC and ultra-fine RGO sheets perform as securer barriers and skeleton which will counteract the microstructure
strain and accelerate electron transfer at the same time. Remarkably, the
self-supporting electrode realizes a distinguished performance of 901 mAh g
-1at 2 A g
-1 for 500 cycles. When matched with LiFePO
4 cathodes, high stability
of more than 100 cycles has been realized for the
full batteries.