High performance aqueous zinc battery enabled by potassium ion stabilization

Abstract

Aqueous zinc ion batteries (AZIBs) are highly competitive in the energy storage systems due to their feature with operation safety and environmental friendliness. However, the sluggish diffusion kinetics of Zn2+ and inferior cathode circulation hinder their widespread application. Herein, we assemble a highly durable zinc ion battery by intercalating K+ into V2O5 nanolayers. The K+ pre-intercalation can buffer the lattice expansion of the electrode materials and reduce the internal stress. In addition, the stable K+ acts as a “pillar” to protect the layered structure of V2O5 materials from collapse during operation cycling. It delivers a reversible capacity of 479.8 mAh g−1 at 0.2 A g−1 and achieves excellent cyclic stability with a retention rate of 91.3% (10 A g−1) after 3000 cycles. The cell still maintains excellent specific capacity at high work temperature.