Self-Healable Hydrogel Electrolyte toward High-Performance and Reliable Quasi-Solid-State Zn-MnO₂ Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Zinc-ion batteries offer potential for energy storage but face challenges like zinc dendrite formation and interfacial side reactions.
• These issues hinder the practical application and long-term stability of zinc-ion battery systems.

Purpose of the Study:

• To develop a self-healable hydrogel electrolyte to overcome the limitations of zinc dendrite growth and side reactions in zinc-ion batteries.
• To evaluate the electrochemical performance and reliability of a quasi-solid-state Zn-MnO2 battery utilizing the novel hydrogel electrolyte.

Main Methods:

• Fabrication of a self-healable hydrogel electrolyte using carboxyl-modified poly(vinyl alcohol) cross-linked by COO-Fe bonds.
• Incorporation of Zn(NO3)2 and MnSO4 into the electrolyte formulation.
• Testing of a quasi-solid-state Zn-MnO2 battery with the hydrogel electrolyte under cycling conditions.
• Assessment of battery performance, including specific capacity, cycle retention, and robustness after physical damage.

Main Results:

• The hydrogel electrolyte effectively suppressed zinc dendrite growth and interfacial side reactions.
• The quasi-solid-state Zn-MnO2 battery achieved a specific capacity of 177 mAh g-1 after 1000 cycles with 83% retention.
• The battery demonstrated autonomous recovery of energy-storage functions after physical damage, indicating excellent robustness.

Conclusions:

• The self-healable hydrogel electrolyte presents a viable strategy to enhance the performance, reliability, and durability of zinc-ion batteries.
• This approach addresses critical challenges in light-metal battery systems, paving the way for more practical applications.