Enhancing the low-temperature performance in lithium ion batteries of Nb2O5 by combination of W doping and MXene addition

The negative electrode working safely at low temperature can guarantee the safe use of lithium ion battery in cold climate. However, currently used graphite negative electrode suffers the potential danger of lithium dendrite growth especially at low temperature. Herein, a series of W-doped Nb2O5/MXene composites are designed to boost the electrochemical performance of Nb2O5 at low temperature. As negative electrode in lithium ion batteries, the designed nanocomposites displayed boosted electrochemical performance at −10 and −20 °C. At −20 °C, the Nb2O5/MXene with 3% W doping displays high reversible capacity (160.7 mAh g−1 at 0.1 A g−1), excellent rate capability (108.6 mAh g−1 at 1 A g−1) and good cycling performance (∼96.3% within 500 cycles), showing significant boost in electrochemical performance. The combination of MXene addition and W doping play a vital role in boosting the electrochemical performance of Nb2O5 at low operation temperature. In consideration of the inherent safety, improved cycling stability, and enhanced rate capability at low operation temperature, the as-designed Nb2O5/MXene can be promising negative electrode for lithium ion batteries to overcome the safety issue at low temperature. •W-doped Nb2O5/MXene nanocomposites are prepared via a facile method.•MXene and W doping improve the electrical conductivity of Nb2O5 electrode.•The optimized electrode delivers 108.6 mAh g−1 at 1 A g−1 at −20 °C.•Nb2O5/MXene anode retains 96.3% of capacity after 500 cycles at −20 °C.