Autocatalytic Eutectic Gel Electrolyte for Quasi-Solid State Zn-Ion Cells

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Hydrated eutectic electrolytes show promise for zinc-ion batteries but suffer from electrode reactivity, leading to dendrite growth and cathode dissolution.
• Existing gelation methods often leave reactive residues, further degrading battery interfaces and performance.

Purpose of the Study:

• To design a novel, initiator-free gel electrolyte for zinc-ion batteries that overcomes the limitations of traditional methods.
• To enhance the stability and longevity of zinc-ion batteries by preventing electrode interface degradation.

Main Methods:

• Developed an autocatalytic acrylamide eutectogel electrolyte, eliminating the need for traditional initiators.
• Investigated the in situ conversion of residual acrylamide into a protective nitrogen-containing interphase during battery cycling.
• Tested the performance of Zn||NaV3O8·1.5H2O cells using the novel electrolyte.

Main Results:

• The initiator-free gel electrolyte significantly reduced residual monomers and initiators.
• The in situ formed interphase suppressed hydrogen evolution and cathode dissolution.
• Tested cells achieved a capacity of 172.7 mAh g⁻¹ with 98.5% retention over 2450 cycles at 1.0 A g⁻¹.
• Stable cycling was observed across a wide temperature range (-20°C to 65°C).

Conclusions:

• The autocatalytic polymerization strategy offers a scalable approach for developing high-performance, long-life quasi-solid zinc batteries.
• This method effectively mitigates interfacial instability and enhances electrochemical performance.
• The strategy shows potential for application with other polymer monomers and Lewis acid salts in advanced battery systems.