Probing Enhanced Electrochemical Performance of Poly (3,4‐ethylenedioxy Thiophene) Encapsulated 5.3 V Spinel LiCoMnO ₄ Cathode for Li‐ion Batteries

Abstract Herein, the effect of poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT) coating is reported on the electrochemical properties of high voltage, 5.3 V lithium cobalt manganese oxide (LiCoMnO ₄ , LCMO) cathodes. Scalable precipitation followed by a wet coating method is employed for the synthesis of LCMO@PEDOT. Various analytical studies are performed to validate the performance of the cathode. The cycling profile exhibits an enhanced electrochemical performance among the LCMO@PEDOT compared to that of pristine LCMO in a half‐cell configuration. Also, the LCMO@PEDOT: 0.5–3 wt.% is optimized to show better electrochemical performance. The diffusion coefficient calculated from both cyclic voltammetry and electrochemical impedance spectroscopy (EIS) exhibits an increase in the magnitude from PEDOT coating of 0.5 to 3 wt.% in the order of ≈10 ⁻¹² cm ² s ⁻¹ . An in‐operando X‐ray diffraction and in‐situ EIS are performed to validate the electrochemical activity. The full‐cell assembly is also fabricated with spinel Li ₄ Ti ₅ O ₁₂ (LTO) anode under balanced loading conditions. The LCMO@PEDOT (1–3 wt.%)/LTO exhibits better electrochemical performance compared to pristine LCMO/LTO. In addition, a temperature study of full‐cell is carried out within the range of −10 to 20 °C and compared.