Water-Capture Filter Paper Separator Realizing Ambient Li-Air Battery

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-air batteries (LABs) show great promise for energy storage but face challenges with lithium metal anode stability.
• Dendrite growth and water crossover are critical issues hindering practical LAB development.

Purpose of the Study:

• To investigate cellulose-based filter paper (FP) as a separator for ambient lithium-air batteries.
• To suppress lithium dendrite growth and prevent water crossover using FP.

Main Methods:

• Utilized cellulose-based filter paper (FP) as a separator in ambient Li-air batteries.
• Employed thermogravimetric analysis and molecular spectroscopy to characterize FP.
• Evaluated battery performance, including cycle life and electrolyte requirements, compared to glass fiber separators.

Main Results:

• FP effectively suppresses dendrite growth and H2O crossover in ambient Li-air batteries.
• Cellulose's surface functional groups enhance ion conductivity and mitigate anode corrosion by capturing water.
• FP separators require less electrolyte and achieve prolonged, stable cycle life compared to commercial glass fiber separators.

Conclusions:

• Cellulose-based filter paper is a cost-effective, renewable, and environmentally friendly separator for practical lithium-air batteries.
• Capturing water on the separator surface is a viable strategy for enhancing LAB stability and performance.
• This study offers insights for designing advanced separators for commercializing lithium-air batteries.