Developing cathode materials integrating good rate performance and sufficient cycle life is the key to commercialization of aqueous zinc-ion batteries. The hyperstable Zn 0.52 V 2 O 5-a ⋅1.8 H 2 O (ZVOH) cathode with excellent rate performance has been successfully developed via an in situ self-transformation from zinc-rich Zn 3 V 3 O 8 (ZVO) in this study. Different from the common synthetic method of additional Zn 2+ pre-insertion, ZVOH is obtained from the insertion of structural H 2 O and the removal of excess Zn 2+ in ZVO, ensuring the lattice structure of ZVOH remains relatively intact during the phase transition and rendering good structural stabilities. The ZVOH delivers a reversible capacity of 286.2 mAh g -1 at 0.2 A g -1 and of 161.5 mAh g -1 at 20 A g -1 over 18 000 cycles with a retention of 95.4 %, demonstrating excellent rate performance and cyclic stability. We also provide new insights on the structural self-optimization of Zn x (CF 3 SO 3 ) y (OH) 2x-y ⋅n H 2 O byproducts and the effect on the mobility of Zn 2+ by theoretical calculations and experimental evidence.