A facile
and effective method to modify Li anode for Li–S cells by exposing
Li foils to tetrahydrofuran (THF) solvent, oxygen atmosphere and trimethylsilyl
chloride ((CH<sub>3</sub>)<sub>3</sub>SiCl) liquid in sequence is
proposed. The results of SEM and XPS show the formation of a homogeneous
and dense film with a thickness of 84 nm on Li metal surface. AC impedance
and polarization test results show the improved interfacial stability.
The interfacial resistances as well as polarization potential difference
have obviously decreased as compared with that of a pristine Li anode.
CV and charge–discharge test results demonstrate that more
reversible discharge capacity and higher Coulombic efficiency can
be achieved. Specific capacity of 760 mAh g<sup>–1</sup> and
an average Coulombic efficiency of 98% are retained after 100 cycles
at 0.5<i>C</i> without LiNO<sub>3</sub> additive. Additionally,
the Li–S cell with a modified Li anode displays a greatly improved
rate performance with ∼425 mAh g<sup>–1</sup> at 5<i>C</i>, making it more attractive and competitive in the applications
of high-power supply
