Robust Biomass Hydrogel Electrolyte via Cytoplasm Reconstruction for Ah-Level Aqueous Batteries

Area of Science:

• Materials Science
• Electrochemistry
• Sustainable Energy

Background:

• Developing sustainable and economic biomass hydrogel electrolytes is crucial for solid-state aqueous batteries.
• Current challenges include achieving robust mechanical strength and high ion conductivity.

Purpose of the Study:

• To propose a biomass-cytoplasm reconstruction strategy for creating high-performance hydrogel electrolytes.
• To demonstrate the fabrication of a novel biomass hydrogel electrolyte using an energy-efficient brining technique.

Main Methods:

• Utilized a facile and energy-efficient brining technique for biomass hydrogel electrolyte fabrication.
• Employed a biomass-cytoplasm reconstruction strategy involving polysaccharide/protein cytoplasm rearrangement.
• Tested kombu-based hydrogel electrolytes in zinc metal batteries and aluminum metal batteries.

Main Results:

• Achieved a biomass hydrogel electrolyte with 11.6 MPa mechanical strength, 20.27 mS cm⁻¹ ion conductivity, and 1.4 × 10⁻⁵ cm² s⁻¹ diffusion coefficient.
• Demonstrated high current discharge (100 mA cm⁻²) and ultra-wide working temperatures (-60°C to 80°C) in zinc metal batteries.
• Verified universality in aluminum metal batteries, achieving threefold cost reduction and enhanced sustainability compared to petroleum-based electrolytes.

Conclusions:

• The biomass-cytoplasm reconstruction strategy provides a new prototype for designing high-performance hydrogel electrolytes for aqueous batteries.
• This approach offers significant cost reductions and sustainability advantages, aligning with green development principles.
• The developed hydrogel electrolytes enable stable cycling life and practical energy storage system integration.