Multimodal electrolyte architecting for static aqueous zinc-halogen batteries.

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Aqueous zinc-halogen batteries (AZHBs) are attractive for energy storage due to zinc's potential and abundance.
• Current AZHBs suffer from capacity decay caused by zinc corrosion and halogen shuttling, limiting their lifespan.
• Instability of high-valence halides restricts multi-electron reactions, hindering energy density.

Purpose of the Study:

• To review the fundamentals, challenges, and recent advancements in AZHBs.
• To emphasize the critical role of electrolyte design for simultaneous optimization of Zn anode and halogen cathode.
• To discuss effective testing and evaluation protocols for synchronous electrolytes.

Main Methods:

• Literature review of AZHB fundamentals and challenges.
• Analysis of electrolyte design strategies for synchronous electrode optimization.
• Discussion of proposed electrolyte approaches: biphasic, gradient hydrogel, and ionic liquid electrolytes.

Main Results:

• Identified zinc corrosion and halogen shuttling as primary limitations in AZHBs.
• Highlighted the necessity of electrolyte engineering for stable Zn metal anodes and efficient halogen cathodes.
• Proposed advanced electrolyte systems to address current challenges.

Conclusions:

• Synchronous electrolyte optimization is crucial for enhancing the reversibility and lifespan of AZHBs.
• Biphasic, gradient hydrogel, and ionic liquid electrolytes offer potential solutions for high-performance AZHBs.
• Further research in electrolyte design can pave the way for practical AZHBs with high energy density and longevity.