| abstract |
Positive electrodes for secondary batteries formed with a plurality of substantially aligned flakes within a coating. The flakes can be formed from metal oxide materials and have a number average longest dimension of greater than 60 μm. A variety of metal oxide or metal phosphate materials may be selected such as a group consisting of LiCoO 2 , LiMn 2 O 4 , Li(M1 x1 M2 x2 Co 1-x1-x2 )O 2 where M1 and M2 are selected from among Li, Ni, Mn, Cr, Ti, Mg, or Al, 0≦x1≦0.5 and 0≦x2≦0.5, or alternatively, LiM1 (1-x) Mn x O 2 where 0<x<0.8 and M1 represents one or more metal elements. Methods for making positive electrode materials are also provided involving the formation of structures with a desired longest dimension, preferably polycrystalline flakes. A cathode coating containing polycrystalline flakes may be deposited onto a conductive substrate and pressed to a desired final electrode thickness. |