Nanofluid Electrolyte with Fumed Al2O3 Additive Strengthening Zincophilic and Stable Surface of Zinc Anode toward Flexible Zinc-Nickel Batteries

Flexible zinc-nickel batteries (FZNBs) have been considered as a promising power supply for wearable electronics due to the intrinsic safety, high operating voltage and superior rate performance. However, the serious self-corrosion of zinc and the redistribution of dissolved [Zn(OH)(4)](2-) on the electrode surface limit the electrochemical performance of FZNBs. Herein, the nanofluid electrolyte with fumed Al2O3 additive is introduced into FZNBs and a protective layer is formed due to the adsorption of Al2O3 on the electrodeposited zinc anode. The protective layer strengthens the zincophilicity of the anode and homogenizes the deposition of [Zn(OH)(4)](2-), avoiding the dendrite formation and the shape change of electrode. Meanwhile, by suppressing the [Zn(OH)(4)](2-) diffusion from the anode surface to the bulk electrolyte, the interface stabilization is effectively promoted, thereby improving zinc utilization rate and inhibiting the corrosion. Hence, the FZNBs assembled with Al2O3-nanofluid electrolyte and electrodeposited zinc anode demonstrates superior energy density of 210 Wh L-1 with a stable cycling of 575 h. Furthermore, FZNBs modified with Al2O3-nanofluid electrolyte have a promising future in the field of wearable and portable electronics.

Automated summary

By introducing a nanofluid electrolyte with aluminum oxide additive, a protective layer is formed on the electrodeposited zinc anode, which enhances its zincophilicity and homogenizes the deposition of zinc hydroxide to prevent dendrite formation and electrode shape change. Additionally, the diffusion of zinc hydroxide from the anode surface to the bulk electrolyte is suppressed, promoting interface stabilization, improving zinc utilization rate, and inhibiting corrosion. As a result, the flexible zinc-nickel batteries assembled with aluminum oxide-nanofluid electrolyte and electrodeposited zinc anode exhibit superior energy density of 210 Wh L-1 and stable cycling for 575 hours, showing promising potential in the field of wearable and portable electronics.