A 1.5 mm amplitude of lateral oscillation was used for the sieving. Sieving was considered complete when the mass of powder in the lowest pan increased by <5% in 10 min, which resulted in approximately 30 min of total sieving time. The appropriately sized Li 2 CO 3 and the TM (oxy)hydroxide precursors were mixed using a tube mill (IKA Tube Mill control) at 5,000 rpm for three runs of one min, with manual agitation performed in between tube mill runs. A mass ratio of 0.5542g Li 2 CO 3 per 1g of TM (oxy)hydroxide precursor was used, corresponding to a very small (<2%) molar Li excess. This mixture was placed in an alumina combustion boat and calcined in a tube furnace under controlled gas atmosphere obtained by mixing Ar and O 2 to achieve the desired p O2 and flow rate, typically 21% O 2 and 200 sccm in a tube with an outer diameter of 4 cm. Calcination involved a ramp at 1.5 °C/min to 900 °C, a 5 hour hold at 900 °C, and natural cooling.