Highly robust zinc metal anode directed by organic–inorganic synergistic interfaces for wearable aqueous zinc battery

Abstract

Flexible aqueous zinc batteries (FAZBs) with high safety and environmental friendliness are promising smart power sources for smart wearable electronics. However, the bare zinc anode usually suffers from damnable dendrite growth and rampant side reaction on the surface, greatly impeding practical applications in FAZBs. Herein, a composite polymer interface layer is artificially self‐assembled on the surface of the zinc anode by graft‐modified fluorinated monomer (polyacrylic acid‐2‐(Trifluoromethyl)propenoic acid, PAA‐TFPA), on which an organic–inorganic hybrid (PAA‐Zn/ZnF2) solid electrolyte interface (SEI) with excellent ionic conductivity is formed by interacting with Zn2+. Both the pouch cell and fiber zinc anode exhibit excellent plating/stripping reversibility after protecting by this organic–inorganic SEI, which can be stably cycled more than 3000 h in symmetric Zn||Zn cells or 550 h in fiber Zn||Zn cells. Additionally, this interface layer preserves zinc anode with excellent mechanical durability under various mechanical deformation (stably working for another 1200 h after bending 100 h). The corresponding PAA‐Zn/ZnF2@Zn||MnO2 full cell displays an ultra‐long life span (79% capacity retention after 3000 cycles) and mechanical robustness (85% of the initial capacity for another 3000 cycles after bending 100 times). More importantly, the as‐assembled cells can easily power smart wearable devices to monitor the user's health condition.

Activating and Stabilizing a Reversible four Electron Redox Reaction of I−/I+ for Aqueous Zn‐Iodine Battery

“…[1][2][3] The emerging aqueous zinc ion batteries have received intense attentions, [4][5][6][7] and great efforts have been made to improve the electrochemical performance of aqueous zinc ion batteries. [8][9][10][11] However, the energy density of aqueous zinc ion batteries is greatly affected by the low energy density, low potential and low power density of cathode materials in comparison to the zinc anode. [12,13] Compared with the Zn 2 + de/intercalation cathode material (including V-based, Mn-based and PBA etc.…”