Multiphase LiNi 0.33 Mn 0.54 Co 0.13 O 2 Cathode Material with High Capacity Retention for Li‐Ion Batteries

An integrated layered‐spinel LiNi 0.33 Mn 0.54 Co 0.13 O 2 material was synthesized through a self‐combustion reaction (SCR), characterized by using X‐ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), and Raman spectroscopy. It was studied as a cathode material for Li‐ion batteries and its electrochemical performance was compared with that of the layered cathode material LiNi 0.33 Mn 0.33 Co 0.33 O 2 when operated over a wide potential window. The Rietveld analysis of LiNi 0.33 Mn 0.54 Co 0.13 O 2 indicated the presence of monoclinic Li[Li 1/3 Mn 2/3 ]O 2 (31 %) and rhombohedral (LiNi x Mn y Co z O 2 ) (62 %) phases as the major components, and the spinel (LiNi 0.5 Mn 1.5 O 4 ) (7 %) as a minor component, which is supported by TEM and electron diffraction analyses. A discharge specific capacity of about 170 mAh g −1 is obtained in the potential range of 2.3–4.9 V versus Li at low rate (C/10) with excellent capacity retention upon cycling. On the other hand, LiNi 0.33 Mn 0.33 Co 0.33 O 2 (NMC111) synthesized through SCR exhibits an initial discharge capacity of about 208 mAh g −1 in the potential range of 2.3–4.9 V, which decreases to a value of 130 mAh g −1 after only 50 cycles. In turn, the multiphase structure of LiNi 0.33 Mn 0.54 Co 0.13 O 2 seems to stabilize the behavior of this cathode material, even when polarized to high potentials. LiNi 0.33 Mn 0.54 Co 0.13 O 2 shows superior retention of the average discharge voltage upon cycling, as compared to that of LiNi 0.33 Mn 0.33 Co 0.33 O 2 when cycled over a wide potential range. Overall, LiNi 0.33 Mn 0.54 Co 0.13 O 2 can be considered as a promising low‐cobalt‐content cathode material for Li‐ion batteries.