Apparent activation energy of multicomponent transition metal oxalates to probe synthesis of battery precursor materials

In this study the apparent activation energy of pure and multicomponent transition metal oxalate coprecipitation reactions were experimentally measured via time dependent extinction of light passing through the reaction solution. These measurements provide a quantitative descriptor of the influence of the relative transition metal composition on the nucleation and growth processes of the precipitates. The resulting crystal structures of the synthesized precursors were also determined and put into the context of the measured coprecipitation apparent activation energies, revealing that the apparent activation energy may indicate impurity or secondary phase formation before it was detectable with X-ray diffraction. This paper is the first report of using apparent activation energies to investigate battery precursor coprecipitation reactions, and these methods should be extendable to chemistry for coprecipitation of many multicomponent transition metal particles which have applications in multiple fields including energy storage materials. Coprecipitation induction periods were measured quantitatively by tracking extinction of light as a function of time at different temperatures. Calculated apparent activation energies from the induction times were then used to provide insights into the synthesis process for multicomponent particles commonly used as battery material precursors. [Display omitted] •Activation energy study conducted on metal oxalate coprecipitation reactions.•Apparent activation energies measured via time dependent extinction of light.•New phase formation possibly indicated by local minimum of activation energies.•Activation energy was quantitative descriptor for multicomponent coprecipitation.