Synergistic Coupling of High Capacity Li1.2Mn0.54Ni0.13Co0.13O2 and High Voltage LiMn1.6Ni0.4O4 Lithium-Ion Battery Cathodes

Manganese−based cathode materials are good alternatives to nickel-based layered cathodes in lithium-ion batteries due to the much cheaper cost of manganese ores. Coprecipitation is a popular method to produce precursor materials for lithium-ion batteries since its versatility enables the synthesis of a wide range of compositions with various architectures. In this study, spherical 2-µm to 4-µm-diameter binary Mn0.8Ni0.2CO3 and ternary Mn4/6Ni1/6Co1/6CO3 precursor materials were synthesized by tuning synthesis conditions including temperature, feeding mode and reagent quantity. The binary and ternary precursor materials were mixed and reacted with Li2CO3 at 800°C to obtain LiMn1.6Ni0.4O4 and Li1.2Mn0.54Ni0.13Co0.13O2 cathode materials, respectively. LiMn1.6Ni0.4O4 had a discharge capacity of 132 mAh g−1 and exhibited excellent cycle life and voltage retention. On the other hand, 221 mAh g−1 discharge capacity was achieved with Li1.2Mn0.54Ni0.13Co0.13O2 , but it showed a fast capacity and voltage decay. A hybrid electrode made of 50:50 wt% of both cathodes yielded 166 mAh g−1 capacity and 3.95 V average discharge voltage with much reduced voltage decay and capacity fading rate, thereby mitigating each other’s weakness in the process.