Enhancement of De‐Solvation Kinetics on V<sub>5</sub>O<sub>12</sub>•6H<sub>2</sub>O Cathode Through a Bi‐Functional Modification Layer for Low‐Temperature Zinc‐Ion Batteries
Xiaodi Jiang, Tongde Wang, Mingze Ji, Donghwan Ji, Shengyuan Deng, Guohua Gao, Jun Shen, Guangming Wu
Abstract
Abstract Zinc‐ion batteries (ZIBs) show great promise for next‐generation energy storage, but their performance at low temperatures is severely hindered by sluggish desolvation kinetics at cathode‐electrolyte interface. To address this limitation, a zincophilic‐hydrophobic poly(3,4‐ethylenedioxythiophene) (PEDOT) modified layer is proposed on V 5 O 12 •6H 2 O cathode. Ab initio molecular dynamics simulations indicate that this modification strategy promotes Zn 2 ⁺ adsorption and reduces the free energy for dissociating hydrated Zn 2+ to form Zn 2+ at the cathode‐electrolyte interface, across the temperature of 280 to 240 K. As a result, this PEDOT‐modified cathode exhibits significantly improved Zn 2 ⁺ diffusion and desolvation kinetics, delivering superior rate performance with a remarkable capacity of 226.5 mAh g⁻¹ at 40 A g⁻¹. Notably, even at −30 °C, this cathode maintains a high capacity of 268.3 mA g⁻¹ at 0.2 A g⁻¹ and exhibits robust capacity retention (92.4%) over 1,000 cycles at 1 A g⁻¹. This approach markedly improves low‐temperature capacity retention and operational efficiency, highlighting the potential of cathode‐electrolyte interface engineering to advance zinc‐ion batteries performance in cold environments.