A method of preparing insoluble transition metal compound particles is described, comprising: providing a transition metal salt solution having the formula (TM)(S) wherein TM is one or more of Mn, Ni, Co, Mg, Zn, Ca, Sr, Cu, Zr, P, Fe, Al, Ga, In, Cr Ge or Sn; providing a source of a carbonate-, hydroxide-, phosphate-, oxyhydroxide- or oxide-based anionic compound wherein the anionic component, represented by S′, is reactive with TM to form the particles; adding the transition metal salt solution and anionic compound to a reaction chamber; and subjecting the chamber to sonication at an intensity of about 0.1 to about 50 W/mL. In an exemplary embodiment, MnCO3 particles are formed from: MnSO4; and Na2CO3 and/or NH4HCO3, wherein the ratio of MnSO4 to Na2CO3 and/or NH4HCO3 is from about 1:1.5 to 1.5:1. The particles may have narrow size distribution and a tap density of about 1.7-2.3 g/mL.