Initial
Coulombic efficiency (ICE) is critical for determining
the energy density of lithium-ion batteries (LIBs) used for practical
applications; however, it is typically disregarded in anode research.
We used SiO
x
and graphite composite anodes
for commercial lithium-ion batteries in our preliminary research to
achieve a balance between ICE, capacity, and cycling life. ICE reached
88%; however, it needs further improvement for commercial applications.
Prelithiation is a process that involves the introduction of extra
lithium ions into LIBs during their manufacturing to enhance the overall
performance of the LIBs. We applied a chemical prelithiation method
on our SiO
x
/graphite composite anodes,
which comprised 95 wt % of the active material mass loading on the
electrode. The ICE increased from 88% to 98% using an aryllithium
reagent impregnation method within 2 min of prelithiation. The anode’s
specific capacity density, rate, and cycle performance also significantly
improved. Scanning electron microscopy (SEM) imaging enhanced by an
osmium tetroxide staining method indicated that the P-anode contained
a stable solid electrolyte interface (SEI) layer after the prelithiation
process and cycling electrochemical test. The P-anode’s stable
charge differential peak over 500 cycles also showcases a robust artificial
SEI layer that was generated by the prelithiation procedure. This
prelithiation process has significant potential for adoption in the
LIB industry’s current electrode manufacturing process.