Synthesis and characterization of LiNi_(0.5)Mn_(1.5)O_4 cathode materials for lithium ion batteries by solid state method

LiNi0.5 Mn1.5O4 cathode materials were synthesized by solid state method using Ni( CH3 COO) 2·4H2O,Mn( CH3 COO) 2·4H2O as starting materials,then decomposed to get nickel manganese oxides at 400 and 500℃ for 3 or 7h,joined and mixed the source of lithium Li2CO3. The sample was calcined in air at 800℃ for 12h and then annealed at 600℃ for 24h. XRD,SEM,EIS and charge-discharge performance tests showed that LiNi0.5Mn1.5O4 delivered the best electrochemical performance by used precursor made at 400℃ for 7h. Its initial specific discharge capacity was 141.5mAh/g when 0.1C charge-discharge at room temperature,and after 30 cycles the capacity retention was 98. 59%; when charged-discharged at 1C initial capacity was 120.34mAh / g,and after 30 cycles the capacity was 112.09mAh/g.