One-step electrochemical in-situ Li doping and LiF coating enable ultra-stable cathode for sodium ion batteries

Using Highly Electronegative Zn to Regulate the Superlattice Structure for the Na-Ion Layered Oxide Cathode with Superior Electrochemical Performance

“…In addition, the characteristic peaks of unmodified LNM at 390 and 651 cm –1 disappear when the solution is charged to high voltage. The peak at 651 cm –1 belongs to the characteristic peak arising from the Na + /vacancy ordering transition, with the peak at 390 cm –1 representing the Li/Mn superlattice structure . The high-spin Mn 3+ will cause Jahn–Teller distortion during charging and discharging, which will destroy the Li/Mn superstructure and lead to the deterioration of its structural stability.…”

“…The peak at 651 cm −1 belongs to the characteristic peak arising from the Na + /vacancy ordering transition, with the peak at 390 cm −1 representing the Li/Mn superlattice structure. 45 The high-spin Mn 3+ will cause Jahn− Teller distortion during charging and discharging, which will destroy the Li/Mn superstructure and lead to the deterioration of its structural stability. The characteristic peaks of Zn0.03-LNM are stable throughout the charge−discharge process.…”

Enhancing the Integral Structural and Thermal Stability of Ultrahigh-Ni Cathodes via Morphology Refinement and In Situ Interfacial Engineering

“…The initial (dis)charge curves of single modified samples with different concentrations at 1 C are shown in Figure S6a, which indicates that the discharge capacity of NCM-F is higher than that of NCM. The in situ epitaxially generated LiF coating layer is a fast electron transfer and lithium-ion diffusion channel, which is conducive to the conductivity of the electrolyte and cathode interface, 35 thereby accelerating the (de)solvation of lithium ions and improving discharge specific capacity. In Figure 4a, the cyclic performance of NCM-W is better than the original sample.…”

Enhancement of the reversible capacity and cycling stability of sodium cathode materials by Li+ reversible migration

“…The recent study also suggests that the synergistic effect of Li ions and transition metals is important for this irreversible structural transition. 27–29…”

“…The recent study also suggests that the synergistic effect of Li ions and transition metals is important for this irreversible structural transition. [27][28][29] In this study, P2-Na 0.7 Mg 0.2 Mn 0.8 O 2 (NMMO) with a high theoretical capacity was rst synthesized as a cathode material. However, it faces a large challenge in cycling stability due to an irreversible phase transition.…”