| CPC C01G 51/04 (2013.01) [H01M 4/0471 (2013.01); H01M 4/525 (2013.01)] | 5 Claims | 

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               1. A cobalt oxide precursor powder for use in preparing a positive electrode active material, wherein the precursor composition comprises particles having a formula Co1-yAyOx, wherein 1<x≤4/3, 0≤y≤0.05, A comprising at least one element selected from the group consisting of Ni, Mn, Al, Mg, Ti, and Zr, wherein the particles composition has a Fd-3m crystal structure and wherein the particles have a D50≥15 μm and a compressive strength of at least 100 MPa and at most 170 MPa. 
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