This work presents a novel binder-free nitrogen-doped carbon paper electrode (NCPE), which was derived from a N-rich polypyrrole (PPy)/cellulose-chopped carbon filaments (CCFs) composite, for Li-O-2 batteries. The fabrication of NCPE involved cheap raw materials (e.g., Cladophora sp. green algae) and easy operation (e.g., doping N by a carbonization of N-rich polymer), which is especially suitable for large-scale production. The NCPE exhibited a bird's nest microstructure, which could provide the self standing electrode with considerable mechanic durability, fast Li+ and O-2 diffusion, and enough space for the discharge product deposition. In addition, the NCPE contained N-containing function groups, which may promote the electrochemical reactions. Furthermore, binder-free architecture designs can prevent binder-involved parasitic reactions. A Li-O-2 cell with the NCPE displayed a cyclability of more than 30 cycles at a constant current density of 0.1 mA/cm(2). The 1st discharge capacity for a cell with the NCPE reached 8040 mAh/g at a current density of 0.1 mA/cm(2), with a cell voltage around 2.81 V. A cell with the NCPE displayed a coulombic efficiency of 81% on the 1st cycle at a current density of 0.2 mA/cm(2). These results represent a promising progress in the development of a low-cost and versatile paper based O-2 electrode for Li-O-2 batteries. (C) 2015 Elsevier B.V. All rights reserved.