Hierarchical MnCo2O4 nanosheet arrays/carbon cloths as integrated anodes for lithium-ion batteries with improved performance

Abstract

To solve the reduced output voltage caused by the high lithium redox potential of Co₃O₄ when applied as an anode material in full cells, an effective strategy is to partially replace Co by Mn to form MnCo₂O₄ without changing the original crystal structure. Herein, 3D hierarchical MnCo₂O₄ nanosheets arrays grown via a hydrothermal method on carbon cloths, as binder-free anodes for lithium-ion batteries, exhibit a high areal capacity of 3.0 mA h cm⁻² at a current density of 800 μA cm⁻², excellent cycling stability, good rate performances and a discharge voltage plateau of 0.25 V which is lower than that of their Co₃O₄ nanosheet counterparts. Due to the increased output voltage of the full cell induced by the introduction of Mn species with a lower lithium extraction potential, MnCo₂O₄ based full cells display higher or comparative capacity in a certain voltage range compared with Co₃O₄, while still retaining the excellent conductivity of Co₃O₄ electrodes. Our work here paves the way for the design of high performance full cells with Co-based oxide electrodes.