As the demand for safe, low-cost energy storage continues to grow, the limitations of traditional lithium-ion batteries in terms of cost, safety, and resource availability become more pronounced. Now, researchers from Nanjing University of Science and Technology and Nanyang Technological University, led by Professor Wenyao Zhang and Professor Jong-Min Lee, have presented a comprehensive review on rational electrolyte structure engineering for highly reversible zinc metal anodes in aqueous zinc-ion batteries. This work offers valuable insights into the development of next-generation battery technologies that can overcome these limitations.
Why Rational Electrolyte Engineering Matters
· Dendrite Suppression: Rational electrolyte design can effectively suppress zinc dendrite growth by regulating Zn2+ nucleation and deposition behavior, addressing the "dendrite" problem in zinc metal anodes.
· Hydrogen Evolution Reaction (HER) Inhibition: By reconstructing the solvation structure and reducing free water activity, electrolyte engineering can significantly suppress parasitic hydrogen evolution reactions and improve battery safety.
· Interface Stability: Rational electrolyte design enables the formation of stable solid electrolyte interphase (SEI) layers, enhancing the long-term cycling stability and reversibility of zinc metal anodes.
Innovative Design and Features
· Zinc Salt Optimization: The review covers various zinc salts including Zn(CF3SO3)2, Zn(TFSI)2, and high-concentration ZnCl2 systems. Each salt type offers unique properties for different applications, with high-concentration systems showing superior performance in suppressing side reactions.
· Functional Additives: The review discusses five categories of electrolyte additives including electrostatic shielding agents, surface adsorption additives, desolvation modulators, SEI formers, and crystal plane regulators. These additives work synergistically to improve anode performance.
· Advanced Electrolyte Systems: Two common types of advanced electrolytes, hydrated eutectic electrolytes and gel polymer electrolytes, are introduced. These systems offer enhanced stability and reduced water activity for improved battery performance.
Applications and Future Outlook
· Grid-Scale Energy Storage: Rational electrolyte engineering enables aqueous zinc-ion batteries to achieve long cycle life (>25,000 cycles) and high capacity retention, making them suitable for large-scale energy storage applications.
· Flexible Electronics: Gel electrolytes with enhanced mechanical properties and ionic conductivity enable the development of flexible and wearable zinc-ion batteries for portable electronics.
Challenges and Opportunities
The review highlights remaining challenges such as dynamic interface reconstruction, AI-guided additive screening, and extreme condition adaptability. Future research will focus on developing multi-functional synergistic strategies and application-specific electrolyte systems.
This comprehensive review provides a roadmap for the development and application of rational electrolyte structure engineering in aqueous zinc-ion batteries. It highlights the importance of interdisciplinary research in electrochemistry, materials science, and computational modeling to drive innovation in this field. Stay tuned for more groundbreaking work from Professor Wenyao Zhang and Professor Jong-Min Lee's teams!
