Toward Tailorable Zn-Ion Textile Batteries with High Energy Density and Ultrafast Capability: Building High-Performance Textile Electrode in 3D Hierarchical Branched Design

Small. 2018 Sep;14(36):e1802320. doi: 10.1002/smll.201802320. Epub 2018 Aug 14.

Abstract

Rechargeable Zn-ion batteries are promising candidates for wearable energy storage devices. However, their performance is severely restricted by the low conductivity and inferior mass loading. Herein, a new type of the textile based electrodes with 3D hierarchical branched design is reported. Both Ni nanoparticles and carbon nanotubes are used to build conductive coatings on the textiles. The 3D hierarchical nanostructures, consisting of the vertical-aligned nanosheets and the fluffy-like small flakes, grow on the conductive textiles to form the self-supported electrodes. It ensures fast electron/ion transport and high mass loading, and maintains the structure stability during cycling. Two textile electrodes with the NiCo hydroxide and MnO2 self-branched nanostructures are constructed. Their faster kinetics, higher capacity and better rate capability than the solitary nanosheets based counterpart demonstrate the superiority of the hierarchical architecture. Moreover, the solid-state Zn-MnO2 and Zn-NiCo batteries are fabricated based on the textile electrodes and the polymer electrolytes. The high energy density, superior power density and good long-term cycling stability confirm their excellent energy storage ability and fast charge/discharge capability. Particularly, the high safety under various conditions enable them promising candidates for wearable electronics.

Keywords: 3D hierarchical branched structure; Zn-ion textile battery; high energy density; high rate capability.