Different kinds of composite electrode materials containing copper boron oxide Cu3B2O6 as an active component are studied in Li-ion test cells. Cu3B2O6-based electrodes are modified by incorporating 10% w/w of either single-wall/double-wall (SW/DW), multi-wall (MW) carbon nanotubes (CNTs) or reduced graphene oxide (RGO). The studies show an increase of cycling performance for all composites in comparison to the standard mixture with 10% w/w amorphous carbon. The best improvement of specific capacity is achieved for the SW/DW CNT Cu3B2O6 composite. After 30 cycles the capacity is still over 152 mAh/g in comparison to 20 mAh/g for the standard mixture. Electrochemical impedance spectroscopy reveals a significant decrease of the resistivity of the Schottky contacts in the CNTs- and RGO- composites compared to the standard mixture. This supports the conclusion that the main mechanism for the capacity improvement is related to better electronic transport properties of the composites. (C) 2014 The Electrochemical Society. All rights reserved.