Highly reversible lithium storage in hierarchical Ca₂Ge ₇O₁₆ nanowire arrays/carbon textile anodes

Aligned Ca₂Ge₇O₁₆ nanowire arrays were successfully grown on carbon textiles to form hierarchical 3D structures by using a facile hydrothermal method on a large scale. Typical Ca ₂Ge₇O₁₆ nanowires are single crystals that show preferred growth along the [001] direction. The 3D hierarchical structures were used as binder-free anodes for lithium-ion batteries, which showed the features of highly reversible capacity (900-1100 mA h g^-1 at a current density of 300 mA g^-1), remarkable cycling stability, even over 100 cycles, and good rate capability, with a capacity of about 500 mA h g ^-1 at 3 A g^-1. Furthermore, highly bendable full cells were also fabricated, which showed high flexibility, with little voltage change after bending 600 times, and superior temperature tolerance within the range 4-60 °C, thus demonstrating their promising potential for applications in high-performance lithium-ion batteries. Batteries not included: A hierarchical flexible electrode that consisted of aligned Ca₂Ge₇O ₁₆ nanowire arrays on carbon textile (see figure) exhibited a highly reversible capacity, remarkable cycling stability, and good rate capability.