LiNi0.5Co0.2Mn0.3O2-LiMn0.6Fe0.4PO4 Mixture with Both Excellent Electrochemical Performance and Low Cost as Cathode Material for Power Lithium Ion Batteries

LiNi0.5Co0.2Mn0.3O2 (NCM) and LiMn0.6Fe0.4PO4 (LMFP) mixtures are prepared and intensively investigated in a practical level. The 18650 full batteries that are assembled with NCM-LMFP mixtures as cathodes exhibit better rate capability than cells that are utilized LMFP material as the cathode. Moreover, energy densities of 18650 batteries that are fabricated with NCM-LMFP mixtures as cathodes are not largely reduced with the reduced amount of NCM because of the high voltage plateau of LMFP material, but contrary, the cost of cathode materials is remarkably decreased. The cycling stability of batteries that are prepared with NCM-LMFP mixtures as cathodes is better than cells that are assembled with NCM as the cathode. In addition, the low/high-temperature performance of cells that are fabricated with mixture materials as cathodes is superior to batteries that are assembled with LMFP as the cathode. These electrochemical test results demonstrate that NCM-LMFP mixtures combined the advantages of the two materials, implying good synergetic effects between NCM and LMFP materials. Therefore, lithium ion batteries fabricated with NCM-LMFP mixtures as cathodes with high energy density, superior rate capability, long lifetime, excellent temperature adaptability and low cost would be a promising candidate batteries for electric vehicles. (C) 2018 The Electrochemical Society.