Two types of lithium cobalt oxides (LiCoO2) as cathode materials for lithium ion batteries are synthesized from two cobalt sources of different facial-shapes (octahedral and truncated-octahedral Co3O4) and Li2CO3 using solid state synthesis. From X-ray diffraction and scanning electron microscopy measurements, the reaction mechanism of the formation of LiCoO2 is investigated. It is revealed that LiCoO2 from octahedral Co3O4 with only {111} surfaces grows in one direction whereas the crystal orientation of LiCoO2 from truncated-octahedral Co3O4 with {111} and {100} surfaces is not unique and the spinel intermediates of Li x Co2O4 are formed during synthesis. They show largely unequal rate and cycling performances for lithium ion battery, even though their outer appearances are nearly identical. Almost single-crystalline LiCoO2 from octahedral precursors shows much better electrochemical performances than LiCoO2 from truncated-octahedral precursors as a lithium ion battery cathode. By studying crystal orientation, it is shown that the poor electrochemical performances of LiCoO2 from truncated-octahedral Co3O4 are originated by crystal-mismatch between crystallites.