Decoding the Superior Lithium-Ion Storage Capabilities of Oligoaniline-Derived Anodes

The development of high-performance anodes is critical for advancing lithium-ion battery (LIB) technology, and oligoaniline-based materials, such as tri-aniline (T3) and tetra-aniline (T4), have emerged as promising candidates due to their unique electrochemical properties. These materials offer multiple redox-active sites, enabling efficient charge storage and reversible lithium-ion intercalation, while their intrinsic conductivity facilitates rapid electron transport. T3 demonstrates better cycling stability and delivers the outstanding specific capacity of 964.14 mAh g−1 at 100 mA g−1 and 721.09 mAh g−1 at a high current density of 1 A g−1, alongside a higher specific capacity compared to T4. The galvanostatic intermittent titration technique (GITT) reveals enhanced diffusion coefficients of 10−11 cm2 s−1 for T3 and 10−12 cm2 s−1 for T4. In situ electrochemical impedance spectroscopy (EIS) and distribution of relaxation times (DRT) analysis indicate a thinner solid-electrolyte interphase (SEI) layer, reduced charge transfer resistance, and a lower Li+ activation energy in T3, attributed to its higher electrical conductivity. These features collectively result in better transport properties, positioning T3 as a competitive anode material. To further support the experimental findings, density functional theory (DFT) calculations were conducted on both materials. This paper provides a comprehensive evaluation of T3 and T4, highlighting their potential to address key challenges in high-performance LIBs.