Na-ion batteries (NIBS) and Na-ion capacitors (NICs) have tremendous potential in many large-scale energy storage applications. Here, NIBs based on TiO2 nanorods/carbon fiber cloth (TiO2/CFC) flexible anode materials are introduced. The as-prepared flexible anode exhibited a notable rate performance and high specific capacity of 148.7 mAh g(-1) after 2000 cycles at 1 A g(-1). Furthermore, we demonstrate a highly flexible NIC system employing the TiO2/CFC anode and carbon fibers (CFs) as the cathode material. The flexible TiO2/CFC//CFs NIC device achieved a high energy density of 73.8 Wh kg(-1) and high power density of 13,750 W kg(-1), as well as long-term cycling stability over 4000 cycles with a capacity retention of similar to 90%. (C) 2017 Elsevier B.V. All rights reserved.