Fig. 5
Electrochemical analysis of the origin of the improved cycling performance upon fluorine substitution. a Voltage profiles obtained upon first-cycle and second-charge: Li1.15Ni0.375Ti0.375Mo0.1O2 (LN15: red dot), Li1.2Ni0.333Ti0.333Mo0.133O2 (LN20: blue dash), and Li1.15Ni0.45Ti0.3Mo0.1O1.85F0.15 (LNF15: black solid). b First discharge voltage profiles of LN20 (blue) and LNF15 (black) from galvanostatic intermittent titration tests (GITT) after initial charge to 270 mAh g–1: the inset shows the voltage–time GITT profiles around 120 mAh g–1. Each step in GITT curve corresponds to a galvanostatic (dis)charge of an additional 10 mAh g–1 at a rate of 20 mA g–1 and is followed by a five-hour relaxation step. c Discharge profiles of shaker-milled LNF15 (S-LNF15), when charged at 20 mA g–1 and discharged at different rates of 10, 20, 40, 100, 200, and 400 mA g–1 (1.5–4.6 V, 298 K)
