Understanding the different effects of 4d-transition metals on the performance of Li-rich cathode Li₂MnO₃ by first-principles

Abstract

The poor cycle performance of Li-rich cathode Li2MnO3, a promising cathode of the next-generation Li-ion batteries, limits its commercial applications. Transition metal (TM) doping is widely applied to optimize the...

Understanding the electrochemical properties of Mg-doped Li2MnO3: first-principles calculations

“…The Li vacancy formation energy in undoped Li 2 MnO 3 is determined to be within the range of 4.53-4.70 eV, exhibiting excellent agreement with other computationally derived results. 21,58 For Mg-doped Li 2 MnO 3 , we observe a significant reduction in the formation energies of Li vacancies surrounding the Mg dopant. The lowest formation energy is found for the Li vacancies at the We then calculate the average delithiation voltage in different delithiation stages according to the following equation: 59…”

“…Elemental substitution or atomic doping has been commonly employed to enhance the cycling performance and maintain the capacity of Li-rich LIBs. 19,20 Transition metals are widely chosen as dopants and have been extensively studied, [21][22][23][24][25][26] but alkali earth metal doping has also received attention in recent years. It is generally recognized that adding Mg atoms into Li-rich cathode materials has a positive effect on the electrochemical performance.…”

“…31 To elucidate the impact of doping on the electrochemical properties of Li 2 MnO 3 , first-principles calculations have also been conducted. 21,22,[32][33][34][35][36] As for Mg doping, few investigations have been reported in the literature. In 2015, the influence of 10 cationic dopants (Mg, Ti, V, Nb, Fe, Ru, Co, Ni, Cu, and Al) at the Mn site on the phase stability, redox potential, ionic conductivity and electronic conductivity of Li 2 MnO 3 was investigated using density functional theory calculations.…”

Exploring the Phase Stability of Li2Mn1–xTMxO3 (TM = Ni, Co, Cr, Ru) Cathode Materials in Lithium-Ion Batteries via the Cluster Expansion Method

“…This work selected four transition metals, Ni, Co, Ru and Cr, for doping Li 2 MnO 3 at the Mn site. Extensive research has been done on the doping of Ni, 35−40 Co, 39−41 Ru, 38,40,42 and Cr 41,43,44 into LMO. A density functional theory (DFT) + U study presented by Lanjan et al 39 showed that replacing 50% Mn with Ni or Co reduces the band gap and consequently increases the conductivity of Li 2 Mn 0.5 TM 0.5 O 3 .…”

“…This work selected four transition metals, Ni, Co, Ru and Cr, for doping Li 2 MnO 3 at the Mn site. Extensive research has been done on the doping of Ni, − Co, − Ru, ,, and Cr ,, into LMO. A density functional theory (DFT) + U study presented by Lanjan et al .…”