4.8 Article

Unraveling the high Energy efficiency for Zn||metal hexacyanoferrate batteries in a zinc-potassium hybrid configuration

Journal

NANO ENERGY
Volume 104, Issue -, Pages -

Publisher

ELSEVIER
DOI: 10.1016/j.nanoen.2022.107990

Keywords

Energy efficiency; Voltage difference; Charge voltage; Desolvation; Fast diffusion

Funding

  1. National Key R & D Program of China
  2. GRF
  3. ITC of Hong Kong
  4. [2019YFA0705104]
  5. [CityU11212920]

Ask authors/readers for more resources

By selecting a stable cathode framework and suitable tunnels, high energy efficiency for the storage of Zn2+ ions can be achieved. The use of K+ ions as charge carriers also contributes to the reduction of overpotential. This research demonstrates the potential for improving energy efficiency of aqueous zinc batteries and suggests further research directions.
Aqueous zinc batteries suffer from high overpotentials due to the sluggish diffusion of Zn2+ in the host and low potential of the cathode partially owing to the high desolvation energy for the hydrated Zn2+ cations, which lead to the unsatisfactory Energy efficiency although high Coulombic efficiency can be achieved in most cases. Here we achieved a high Energy efficiency up to 89% for the energy storage of Zn2+ ions through selecting cathode with stable frameworks and suitable tunnels. Furthermore, through screening different metal ions, K+ ion stands out due to its weak hydration structure and smallest charge/radius ratio. The overpotential for both Zn2+ and K+ ions were researched, and the dominated factor is the small diffusion barrier of charge carriers in the selected cathode structure. Based on the pre-built cathode and screened charge carrier of K+, a high discharge voltage plateau around 1.9 V was obtained, with a small overpotential (< 0.12 V), thus an extraordinary Energy effi-ciency around 93% that is almost irrelevant to the current density was obtained. We wish our research can arouse attention of community on Energy efficiency of aqueous electrolyte batteries.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.8
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available