Non-spherical Ni_1/3Co_1/3Mn_1/3OOH and spherical Ni_1/3Co_1/3Mn_1/3(OH)₂ precursor powders were synthesized using a two step drying method and a co-precipitation method, respectively. And then high tap-density non-spherical and spherical Li(Ni_1/3Co_1/3Mn_1/3)O₂ powders were prepared from their precursors, which were sintered with LiNO₃. XPS studies indicated that the predominant oxidation states of Ni, Co and Mn in the non-spherical precursor were ＋2, ＋3 and ＋4, respectively. However, those in the spherical precursor were all ＋2. And the XRD studies showed that the activity of non-spherical Ni_1/3Co_1/3Mn_1/3OOH was higher than that of spherical Ni_1/3Co_1/3Mn_1/3(OH)₂, and furthermore, the non-spherical Li(Ni_1/3Co_1/3Mn_1/3)O₂ could be synthesized at a low temperature, which had a well-ordered layered α-NaFeO₂ structure with a small amount of cation mixture. SEM showed that the synthesized non-spherical particles are uniform in size. The tap-density is up to 2.95 g•cm^－3, which is higher than that of spherical powders (2.35 g•cm^－3). Charge and discharge capacity experiments showed that the non-spherical cathodes delivered higher discharge capacity and better charge-discharge cycling property than the spherical powders.

Key words: lithium ion battery, cathode material, LiNi_1/3Mn_1/3Co_1/3O₂, high tap-density