Effect of Cr3+ doping on morphology evolution and electrochemical performance of LiNi0·5Mn1·5O4 material for Li-ion battery

Enhanced Electrochemical Performance of 5V LiNi0.5Mn1.5‐xZrxO4 Cathode Material for Lithium‐Ion Batteries

“…The greater exposure of higher‐surface‐energy facets is believed to be conductive to Li + ions transport kinetics during charge/discharge process, [41,46] thus ensuring higher specific discharge capacity and better rate capability, in consistence with the rate capability results in Figure 4(c). Our previous work on Cr 3+ doping in LNMO material also found that appropriate Cr 3+ doping gave rise to the appearance of higher‐surface‐energy {110} and {311} facets [14] . The Al‐doped LiMn 2 O 4 truncated octahedron reported by Fu et al [29] .…”

“…Our previous work on Cr 3 + doping in LNMO material also found that appropriate Cr 3 + doping gave rise to the appearance of higher-surface-energy {110} and {311} facets. [14] The Al-doped LiMn 2 O 4 truncated octahedron reported by Fu et al [29] also exhibited greater exposure of higher-surfaceenergy {110} and {311} facets, which exhibited enhanced discharge capacity and rate capability.…”

“…This phenomenon is in accordance with our previous work on Cr 3 + doping in LNMO material. [14] The formation of ZrÀ O bond with higher bonding strength than NiÀ O and MnÀ O bonds during high-temperature calcination process may absorb more energy, thus mitigating the phenomena of reducing system energy by the agglomeration of primary particles to some extent. Therefore, the agglomeration gradually abates until complete breakdown with the increase of Zr 4 + doping contents.…”

“…In addition, the stronger ZrÀ O bond can lengthen LiÀ O distance, making Li + ions extraction from the framework much easier, as the same case with Cr 3 + doping. [14,49] On the other hand, the surface orientation also plays an important role in the kinetics of Li + ions diffusion during charge/discharge process. [41,50] It has been reported that the higher-surface-energy {110} and {311} facets are more favorable to Li + ions diffusion during charge/ discharge process compared with {111} and {110} facets, [41] thereby the spinel material with a higher proportion of highersurface-energy facets generally exhibits better rate capability.…”

“…[4,9] Among them, element doping is a widely adopted method to enhance the electrochemical performance of LiNi 0.5 Mn 1.5 O 4 material due to simple techniques and low equipment requirements. [10] A series of elements, including Mg, [11] V, [12] B, [13] Cr, [14] Al + Cu, [15] Sc, [16] Ti, [17] Si, [18] and Co, [19] have been used to substitute partial Ni or/and Mn to improve the electrochemical performance of LiNi 0.5 Mn 1.5 O 4 material. The enhanced electrochemical performances are generally ascribed to elimination of impurities, regulation of cation ordering and Mn 3 + content, promotion of structural stability, and so on.…”