Improved cycle stability and high-rate capability of Li3VO4-coated Li[Ni0.5Co0.2Mn0.3]O2 cathode material under different voltages

Enhanced cycling stability and rate performance of Li[Ni 0.5 Co 0.2 Mn 0.3 ]O 2 by CeO 2 coating at high cut-off voltage

“…In Fig. 9a, the anodic/cathodic peaks of sample-0 in the first cycle are centered at 3.82/3.70 V, which respectively correspond to the delithiation/lithiation process coupled with the oxidation/ reduction of Ni 2þ /Ni 4þ couple [29]. The anodic peaks shift to lower voltage which is generally related to the activation process of the electrode in the initial cycle [24] and the corresponding cathodic peaks remain relatively steady in the subsequent cycles.…”

“…In addition, Li þ diffusion coefficient (D Liþ ) is calculated using the following equation [29,30]:…”

Improving the electrochemical properties of high-energy cathode material LiNi0.5Co0.2Mn0.3O2 by Zr doping and sintering in oxygen

“…According to previous studies [21], R s is the solution resistance, R ct is the charge transfer resistance, CPE is the corresponding constant phase element, and W is related to the solid-state diffusion of lithium ions in active materials corresponding to the straight line at low frequencies.…”

Multifunctional Li2O-2B2O3 coating for enhancing high voltage electrochemical performances and thermal stability of layered structured LiNi0.5Co0.2Mn0.3O2 cathode materials for lithium ion batteries

“…In general, small interrupt corresponds to the impedance of solution (R s ), the first semicircle in high frequency is attributed to the diffusion resistance of lithium ions (R sf ) through the solid electrolyte interface layer, the semicircle later emerged in high to medium frequency represents the charge transfer resistance (R ct ) between the electrode and electrolyte and a sloping line at low frequency which corresponds to the diffusion of lithium ions in the solid electrode (Z w ). [46,47] The obtained EIS spectra are simulated using the equivalent circuit displayed in Fig. 10b and the fitting resistance values are listed in Table 3.…”