TY - JOUR

T1 - Dichlorosilane-derived nano-silicon inside hollow carbon spheres as a high-performance anode for Li-ion batteries

AU - Jaumann, Tony

AU - Gerwig, Maik

AU - Balach, Juan

AU - Oswald, Steffen

AU - Brendler, Erica

AU - Hauser, Ralf

AU - Kieback, Bernd

AU - Eckert, Jürgen

AU - Giebeler, Lars

AU - Kroke, Edwin

PY - 2017/5

Y1 - 2017/5

N2 - A novel and cost-effective synthesis of silicon nanocrystallites (<10 nm) sealed in hollow carbon spheres (nc-Si@HCS) is developed as a promising anode material for high-performance Li-ion batteries (LIBs). The preparation method involves dichlorosilane (H2SiCl2) as widely available feedstock, to form a hydrogen-rich polysiloxane as a precursor for the production of large quantities of silicon nanoparticles. The final electrode material is composed of agglomerated 5 nm sized silicon nanoparticles encapsulated within hollow micro-sized carbon structures. A high specific capacity of 1570 mA h gelectrode−1 at 0.25 A g−1 with a capacity retention of 65% after 250 deep discharge cycles and a reversible high areal capacity of up to 4 mA h cm−2 at a total mass loading of 3.2 mg cm−2 impressively demonstrate the excellent features of this novel anode material. We performed a detailed structural as well as electrochemical characterization in different electrolytes. Post mortem investigations help to understand the degradation mechanism in our material. The study herein heralds a new approach to structurally design advanced negative electrode materials with the potential to increase the specific energy of LIBs and to boost future electro-mobility technology.

AB - A novel and cost-effective synthesis of silicon nanocrystallites (<10 nm) sealed in hollow carbon spheres (nc-Si@HCS) is developed as a promising anode material for high-performance Li-ion batteries (LIBs). The preparation method involves dichlorosilane (H2SiCl2) as widely available feedstock, to form a hydrogen-rich polysiloxane as a precursor for the production of large quantities of silicon nanoparticles. The final electrode material is composed of agglomerated 5 nm sized silicon nanoparticles encapsulated within hollow micro-sized carbon structures. A high specific capacity of 1570 mA h gelectrode−1 at 0.25 A g−1 with a capacity retention of 65% after 250 deep discharge cycles and a reversible high areal capacity of up to 4 mA h cm−2 at a total mass loading of 3.2 mg cm−2 impressively demonstrate the excellent features of this novel anode material. We performed a detailed structural as well as electrochemical characterization in different electrolytes. Post mortem investigations help to understand the degradation mechanism in our material. The study herein heralds a new approach to structurally design advanced negative electrode materials with the potential to increase the specific energy of LIBs and to boost future electro-mobility technology.

U2 - 10.1039/C7TA00188F

DO - 10.1039/C7TA00188F

M3 - Article

VL - 5.2017

SP - 9262

EP - 9271

JO - Journal of Materials Chemistry A

JF - Journal of Materials Chemistry A

SN - 2050-7488

IS - 19

ER -