2024/04/19 by Jayashree Pati, Pati, Jayashree, R. S. Dhaka +1
Engineering · Materials Science · #Advanced Battery Materials and Technologies #Advancements in Battery Materials #Chemical Physics (physics.chem-ph) #Conducting polymers and applications #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci)
paper · pdf · doi:10.48550/arxiv.2404.12822
openalex publication_date 2024/04/19 · openalex created_date 2024/04/23 · openalex updated_date 2026/07/28
We report the electrochemical sodium-ion kiinetics and distribution of relaxation time (DRT) analysis of a newly designed mixed polyanionic NaFe1.6V0.4(PO4)(SO4)2@CNT composite as a cathode. The specific capacity of 104 mAhg-1 is observed at 0.1~C with the average working voltage of ∼3~V. Intriguingly, a remarkable rate capability and reversibility are demonstrated up to very high current rate of 25~C. The long cycling test up to 10~C shows high capacity retention even after 2000 cycles. The detailed analysis of galvanostatic intermittent titration technique (GITT) and cyclic voltammetry (CV) data reveal the diffusion coefficient of 10-8--10-11 cm2s-1. We find excellent stability in the thermal testing between 25--55^∘C temperatures and 80% capacity retention up to 100 cycles at 5~C. Further, we analyse the individual electrochemical processes in the time domain using the novel DRT technique at different temperatures. The \it ex-situ investigation shows the stable and reversible structure, morphology and electronic states of the long cycled cathode material. More importantly, we demonstrate relatively high specific energy of ≈155 Wh kg-1 (considering the total active material loading of both the electrodes) at 0.2~C for full cell battery having excellent rate capability up to 10~C and long cyclic stability at 1~C.