Amorphous Li2 O2 : Chemical Synthesis and Electrochemical Properties

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Aprotic lithium-oxygen (Li-O2) batteries are a promising next-generation energy storage technology.
• The discharge product, lithium-2-oxide (Li2 O2), can exist in crystalline or amorphous morphologies.
• The morphology of Li2 O2 significantly impacts Li-O2 cell performance, but amorphous Li2 O2 is poorly understood due to synthesis challenges.

Purpose of the Study:

• To synthesize pure amorphous Li2 O2.
• To investigate the electrochemical properties of amorphous Li2 O2.
• To compare the performance of amorphous Li2 O2 with crystalline Li2 O2 in Li-O2 batteries.

Main Methods:

• Rapid synthesis of amorphous Li2 O2 using tetramethylammonium superoxide and LiClO4 in solution.
• Characterization of amorphous Li2 O2 using various analytical techniques.
• Electrochemical testing of Li-O2 cells utilizing amorphous Li2 O2 as the discharge product.

Main Results:

• Amorphous Li2 O2 was successfully synthesized and its structure confirmed.
• Amorphous Li2 O2 exhibited enhanced charge-transport properties compared to crystalline Li2 O2.
• Increased electro-oxidation kinetics were observed for amorphous Li2 O2.

Conclusions:

• Amorphous Li2 O2 is a viable and desirable discharge product for advanced Li-O2 batteries.
• The unique properties of amorphous Li2 O2 offer a pathway to improved energy efficiency and rate capability.
• Further research into amorphous Li2 O2 could unlock new possibilities for high-performance lithium-oxygen battery designs.