Effects of lithium excess amount on the microstructure and electrochemical properties of LiNi0.5Mn1.5O4 cathode material

The Synergetic Effect of LiMg0.5Mn1.5O4 Coating and Mg2+ Doping on Improving Electrochemical Performances of High‐Voltage LiNi0.5Mn1.5O4 by Sol‐Gel Self‐Combustion Method

“…As shown in Table , the peak intensity ratios of LNMO and LNMO@LMgMO‐1% are 0.94 and 0.97, respectively, which infers that LNMO@LMgMO‐1% possesses the better stability of structure. Additionally, in spinel structure, the I 111 / I 311 intensity ratio is an important implication for the cation mixing extent between Li + and transition metal ions in LNMO and the higher the I 111 / I 311 intensity ratio, the lower the cation mixing extent . The I 111 / I 311 intensity ratio of LNMO@LMgMO‐1% (2.46) is higher than that of LNMO (2.25), indicating the lower cation mixing extent of the former.…”

“…[29,39] Moreover, previous reports showing that I 311 /I 400 peak intensity ratio can reflect the structural stability of the [Mn 2 ]O 4 spinel frame-work, and metaldoped LiMn 2 O 4 and LNMO with I 311 /I 400 ratios between 0.96 and 1.1 have shown better electrochemical properties. [11,35,40] As shown in Table 1, the peak intensity ratios of LNMO and LNMO@LMgMO-1% are 0.94 and 0.97, respectively, which infers that LNMO@LMgMO-1% possesses the better stability of structure. Additionally, in spinel structure, the I 111 /I 311 intensity ratio is an important implication for the cation mixing extent between Li + and transition metal ions in LNMO and the higher the I 111 /I 311 intensity ratio, the lower the cation mixing extent.…”

“…The reason is related to the ionic radius of Mg 2 + (0.72 Å) being larger than that of Mn 4 + (0.53 Å) and Ni 2 + (0.59 Å). [6,11,31,35] The Mg 2 + ordering is in 16d sites of the Fd-3 m structure, as described in the literature. [29,39] Moreover, previous reports showing that I 311 /I 400 peak intensity ratio can reflect the structural stability of the [Mn 2 ]O 4 spinel frame-work, and metaldoped LiMn 2 O 4 and LNMO with I 311 /I 400 ratios between 0.96 and 1.1 have shown better electrochemical properties.…”

“…Additionally, in spinel structure, the I 111 /I 311 intensity ratio is an important implication for the cation mixing extent between Li + and transition metal ions in LNMO and the higher the I 111 /I 311 intensity ratio, the lower the cation mixing extent. [11,41] The I 111 /I 311 intensity ratio of LNMO@LMgMO-1% (2.46) is higher than that of LNMO (2.25), indicating the lower cation mixing extent of the former. In summary, XRD results confirm that LMgMO and LNMO have the same crystal structure.…”

Synthesis of LiNi0.5Mn1.5O4 via Ammonia‐free Co‐precipitation Method: Insight in the Effects of the Lithium Additions on the Morphology, Structure and Electrochemical properties

“…As for the followed calcination process, one of the main factors is lithium additions. Yunxian Qian et al, Jianling Guo et al and Yuan Xue et al confirmed the importance of lithium additions on morphology, structure and electrochemical properties, but there still exists some inconsistences such as the phase structure changes. Moreover, these factors are also dominated by the precursors to a large extent.…”