Work

Enhancement of De‐Solvation Kinetics on V 5 O 12 •6H 2 O Cathode Through a Bi‐Functional Modification Layer for Low‐Temperature Zinc‐Ion Batteries

Year: 2024

Type: article

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.

Source: Advanced Functional Materials

DOI: 10.1002/adfm.202420686