Lithium-Rich Cathode Precursor Uniformity via Co-Precipitation

The patent applies preliminary action by uniformly distributing transition metals (Ni, Co, Mn) in the precursor particle before the electrochemical charging process. This is achieved through controlled co-precipitation during manufacturing, ensuring that the composition is homogeneous from the start. As a result, when the material is subsequently charged at high voltage to extract lithium and oxygen, the uniform initial distribution prevents localized structural collapse, maintaining both high capacity and composition uniformity throughout the particle.

The patent applies local quality by creating a uniform distribution of transition metals throughout the particle structure, ensuring that each region of the particle has the same compositional characteristics. This homogeneous local environment prevents localized instability that would otherwise lead to manganese elution at high temperatures. The uniform distribution ensures that high capacity can be achieved through high-voltage charging without creating hotspots or weak points where manganese would preferentially leach out.

The patent applies parameter changes by modifying the compositional parameters of the lithium transition metal oxide to create a lithium-rich formulation. Specifically, the material contains excess lithium beyond the stoichiometric amount needed for the conventional layered structure. This compositional parameter change enables the material to achieve reversible capacity greater than 200 mAh/g while still maintaining a manufacturing process based on conventional co-precipitation methods, thus preserving ease of manufacture.