A Si-based
negative electrode for lithium-ion batteries (LIBs)
is produced from methanol solutions of single-nanometer-size B and
P co-doped Si nanoparticles (NPs) by drop-coating the solution on
a substrate in air without using binders and conductive additives.
Stable charge–discharge cycles are observed for films produced
from Si NPs in the size range from less than 2 to 12.5 nm in diameter.
It is shown that the performance and stability of the electrodes
depend strongly on the size. The initial capacity increases with the
size, while the stability decreases. The optimum diameter is ∼7
nm. In the electrode made from 7 nm diameter B and P co-doped Si NPs,
the capacity is ∼3300 mAh/g and the Coulombic efficiency is
∼97% at a charge–discharge rate of 0.2C rate.