Multiple morphology composite cathode materials providing high energy and long cycle life and cells employing the same

Abstract

Provided are electrochemically active composite materials that include a first particle comprising a first composition optionally of LiMO(Formula I) where −0.3≤a≤0.3 and −0.3≤b≤1.3 and where M optionally includes 30 at % to 80 at % Mn and 30 at % to 75 at % Ni, the first particle formed of a polycrystalline morphology having a plurality of crystallites and a grain boundary between adjacent crystallites; and a second particle comprising a second composition optionally of LiM'O(Formula II) where −0.1≤c≤0.3 and −0.2≤d≤0.2, wherein M′ comprises Mn at about 75 at % to about 100 at %, wherein said second composition or a portion thereof with a spinel structure and in the form of a three dimensional polyhedron; and wherein said second particle is within, on or about a surface of said first particle.