A continuous process for producing a material of a battery cell using a system having a mist generator, a drying chamber, one or more gas-solid separators and a reactor is provided. A mist generated from a liquid mixture of two or more metal precursor compounds in desired ratio is dried inside the drying chamber. Heated air or gas is served as the gas source for forming various gas-solid mixtures and as the energy source for reactions inside the drying chamber and the reactor. One or more gas-solid separators are used in the system to separate gas-solid mixtures from the drying chamber into solid particles mixed with the metal precursor compounds and continuously deliver the solid particles into the reactor for further reaction to obtain final solid material particles with desired crystal structure, particle size, and morphology.