3D MnCo₂O4.5 Nanorod Arrays on Ni Foam as Binder-Free Anodes for Li-Ion Batteries.

It is a key to develop novel electrode materials with high energy and power density for advanced batteries to meet the demand of electric vehicles (EVs). Manganese cobalt oxides which can react with a large number of ions from the electrolyte for electrochemical energy storage are developing into the promising electrode materials. In this work, well-ordered MnCo2O4.5 nanorod arrays (MCO NRAs) are prepared on Ni foam by a general route of hydrothermal growth and low-temperature annealing treatment. The samples deliver a high initial capacity of 1402.6 mAh g-1 at the current density of 100 mA g-1 and rate capacity of 528 mAh g-1 when the current density is improved 10 times as binder-free anodes for Li-ion batteries (LIBs). After 60 cycles at the current density of 200 mA g-1, the MnCo2O4.5 nanorods still achieve 603 mAh g-1 with capacity retention of 66% (compared with the second discharge capacity). The superior electrochemical properties are due to the fascinating architecture which increases the reaction area and structural stability, reduces ion and electron transport distance and provides good strain release. Hence, MnCo2O4.5 nanorod arrays are promised as advanced anodes for future LIBs with completely meeting the demand of EVs.