Role of carbon nanotube on preparation of spinel LiNi.sub.0.5Mn.sub.1.5O.sub.4 cathode

Spinel LiNi.sub.0.5Mn.sub.1.5O.sub.4 cathode materials have attracted intensive attention owing to their high operating potential, high theoretical energy density, low cost, and satisfactory safety. However, the practical application of LiNi.sub.0.5Mn.sub.1.5O.sub.4 is plagued by poor intrinsic conductivity and poor cycling stability. In this work, a target carbon nanotube-assisted LiNi.sub.0.5Mn.sub.1.5O.sub.4 is synthesized via the sol-gel method coupled with a two-step calcination process, and then the role of carbon nanotube in the LiNi.sub.0.5Mn.sub.1.5O.sub.4 crystallization is studied. It is shown that the introduction of inexpensive carbon nanotubes realizes an overall coordinating control of the key factors (particle size, crystal surface orientation, Mn.sup.3+ ion concentration, and so on) and thus enhances the electrochemical performances of LiNi.sub.0.5Mn.sub.1.5O.sub.4. This method will reduce the cost of material preparation and effectively promote the practical application of high-voltage spinel LiNi.sub.0.5Mn.sub.1.5O.sub.4.