To synthesise NMC from the leached solution, the amount of dissolved spinel was gravimetrically determined and additional molar quantities of M(SO4)•xH2O (where M = Co, Ni) were added to the solution to obtain the target NMC composition. To remove sulphates from the solution, barium acetate (Ba(C2H3O2)2) was added to trigger the precipitation of BaSO4 (amount determined from the molar ratio of the metals used). The BaSO4 was removed through filtration and the remaining solution was dried at 150°C overnight. The precipitate was retrieved and ground before heating at 350 °C (1h/30°C h -1 /air) with the required amount of LiOH•H2O. NMC materials required a higher final annealing temperature of 850°C (12h/100°C h -1 /O2).