Silicon-based anodes have received widespread attention
because
of their high theoretical capacity, which, however, still faces challenges
for practical applications due to the large volume changes during
repeated charge/discharge processes, despite being developed for many
years. Herein, we explore an electrolyte additive, allyl phenyl sulfone
(APS), to enhance the interfacial stability and long-term durability
of the SiO
x
/C electrode. It is revealed
that additive APS contributes to forming a dense and robust solid
electrolyte interphase film with high mechanical strength and favorable
lithium-ion diffusion kinetics, which effectively suppresses the parasitic
side reactions at the electrode-electrolyte interface. Meanwhile,
the strong interaction between APS and trace water/acid in the electrolyte
is further beneficial for enhancing the interfacial stability. By
incorporating 0.5 wt% APS, the cycling stability of the silicon-based
electrode is significantly improved, reserving a capacity of 777 mAh
g–1 after 200 cycles at 0.5C and 30 °C (79.3%
capacity retention), which well exceeds that of the baseline electrolyte
(57.8% capacity retention). More importantly, additive APS effectively
promotes the cycling performance of the corresponding SiO
x
/C||NCM90 (LiNi0.9Co0.05Mn0.05O2) full battery. This work provides valuable
understanding in developing new electrolyte additives to enable the
commercial application of high-energy density lithium-ion batteries
using silicon-based anodes.