The synergism of nanoplates with habit-tuned crystal and substitution of cobalt with titanium in Ni-rich LiNi_0.80Co_0.15Al_0.05O₂ cathode for lithium-ion batteries

LiNi_0.80Co_0.15Al_0.05O₂ (NCA), as a kind of commercial Ni-rich cathode material, draws significant attention due to its outstanding advantage of high capacity. Here, we synthesize layer LiNi_0.80Co_0.15-xTi_xAl_0.05O₂ (x = 0, 0.03, 0.06, 0.09) nanoplates with {010} electrochemical planes through a facile and versatile approach to improve their cycling life and rate capability. Among all the samples, LiNi_0.80Co_0.09Ti_0.06Al_0.05O₂ nanoplates (NCA-T2) has the most {010} planes exposure. As cathode for Li-ion batteries, NCA-T2 displays the largest discharge capacity of 190.2 mAh g⁻¹ corresponding to the capacity retention of 92.9% after 100 charge/discharge cycles at 0.1 C between 2.7 and 4.3 V. The capacity retention of NCA-T2 is much larger than 80.8% of the pristine NCA nanoplates with no Ti-substitution (NCA-T0). The Ti-substituted NCA-T2 sample displays the capacity retention of 90.6% at 5 C during 500 charge/discharge cycles. It suggests that the synergism of nanoplates with {010} electrochemical active planes and Ti in the Co sites can stabilize the structure and improve the rate capability. In addition, the density functional theory (DFT) calculation illustrates Ti doping can suppress the structure variation of NCA-T2.