Spinel-Li3.5+xTi5O12 coated LiMn2O4 with high surface Mn valence for an enhanced cycling performance at high temperature

Improved elevated temperature performance of commercial LiMn2O4 coated with LiNi0.5Mn1.5O4

“…The A 1g bands of LMO@LNMO (9:1) calcined at various temperatures were appeared at ∼629 cm −1 and the F 2 2g bands of them were observed at ∼504 cm −1 , which also indicated that some Ni 2+ in LiNi 0.5 Mn 1.5 O 4 were diffused to LiMn 2 O 4 to form a LiNi x Mn 2-x O 4 (0 < x < 0.5) surface composition after calcination. This diffusing phenomenon upon high temperature annealing was also observed in other reports [25,26].…”

Synthesis and electrochemical properties of high performance polyhedron sphere like lithium manganese oxide for lithium ion batteries

“…Mn 2+ ion is either deposited as Mn oxide on the anode electrode blocking the Li + transport, which leads to a decreased ion conductivity, or forms metallic Mn clusters damaging the solid electrolyte interphase (SEI) layer [10,11]. Most reported approaches to mitigating the capacity fading are partial substitution of Mn 3+ through chemical doping [12][13][14] or surface coating [15][16][17]. Though doping and surface coating can indeed ameliorate the capacity fading of LiMn 2 O 4 spinel, this performance improvement is obtained at the expense of compromising theoretical capacity [18][19][20].…”

Electrochemical performance of layer–spinel composite cathode materials at elevated temperature and high rate

“…To restraint the manganese dissolution of LiMn 2 O 4 caused by the side reaction, many researchers have attempted to improve the high temperature cyclic performance by controlling surface feature of electrode materials. Up to now, the majority of the coating materials have been carbon [5], inert oxides (such as Al 2 O 3 [6], TiO 2 [7], SiO 2 [8] and CeO 2 [9]), lithium-ion solid electrolytes (such as LLTO [10,11], LATP [12], LLZO [13], LBSO [14] and LASO [15]) and electrode materials (such as Li 4 Ti 5 O 12 [16], LiFePO 4 [17], ZnMn 2 O 4 [18], LiCoO 2 [19] and LiNi 1/2 Mn 1/2 O 2 [20]). In the meantime, spinel LiMn 2 O 4 mixed with different types of insertion compounds [e.g., layered LiMO 2 (M = Ni, Co, and Mn)] exhibits better cycling performance and safety characteristics at high temperatures.…”