Theoretical insights into the electrochemical potential of Cu3Si as an electrode material for lithium-ion batteries

Lithium-ion batteries (LIBs) are a promising alternative to lead–acid batteries, offering environmental benefits and cost effectiveness. Their performance depends on the development of anode materials with high theoretical capacities and rapid ion diffusion. In this study, we investigated the potential of copper silicide (Cu3Si) as an anode material for LIBs using first-principles calculations. The energy versus volume plot and phonon dispersion analysis confirm its structural stability, further supported by a negative formation energy of –1901.8[Formula: see text]eV. Electronic structure analysis revealed that Cu3Si is a semiconductor with an indirect bandgap of 1.71[Formula: see text]eV. Elastic property calculations, including the bulk modulus, Young’s modulus, shear modulus, Zener anisotropy factor, [Formula: see text] ratio and Poisson’s ratio, indicate strong mechanical stability with a soft and flexible nature compared to conventional electrode materials. Electrochemically, Cu3Si exhibits excellent cyclic and electrochemical stability, maintaining a relatively stable voltage profile with minimal polarization, good reversibility, and low overpotential. Among the calculated electrode materials, the Cu3Si composite exhibited superior cycling stability, maintaining over 70% of its initial capacity after 500 cycles. This enhanced performance is attributed to its ability to effectively buffer volumetric changes during lithiation, outperforming both silicon and commercial graphite electrodes. Similarly, voltage–capacity analysis revealed that Cu3Si offers a stable voltage profile with minimal polarization, outperforming silicon and graphite in terms of electrochemical reversibility and cycling stability. These characteristics underscore its potential as a high-performance anode material for next-generation LIBs.