Brain-like manganese monoxide (MnO) microspheres were synthesized by simple precipitation method with subsequent heat treatment. MnO with polyacrylonitrile (PAN) as a binder delivers an initial reversible specific capacity of 976.1 mAh g(-1) and it remains at 912.3 mAh g(-1) after 30 cycles. The excellent cyclic performance is attributed to the effective conductive network of cross-linked PAN that formed during the thermal treatment. FTIR, ex situ XRD and XAS were performed to investigate the excess reversible capacity of MnO. The results show that the excess capacity is partially ascribed to the interfacial lithium storage between nanosized Li2O and Mn which is formed during the conversion reaction. The porous microspheres with large surface area also provide some active sites for lithium storage. (C) 2017 Published by Elsevier B.V.