A Rechargeable Li-CO₂ Battery with a Gel Polymer Electrolyte

Area of Science:

• Electrochemistry
• Materials Science
• Energy Storage

Background:

• Lithium-CO2 batteries offer high theoretical energy density but suffer from poor rechargeability and low current density.
• Conventional Li-CO2 batteries using liquid electrolytes face challenges with discharge product morphology and stability.

Purpose of the Study:

• To develop a rechargeable Li-CO2 battery with enhanced electrochemical performance using a gel polymer electrolyte (GPE).
• To investigate the impact of GPE on the formation and morphology of discharge products in Li-CO2 batteries.

Main Methods:

• Fabrication of a rechargeable Li-CO2 battery employing a GPE composed of a polymer matrix and a tetraglyme-based liquid electrolyte.
• Utilization of a carbon nanotube-based gas electrode.
• Characterization of the discharge product morphology and crystallinity.

Main Results:

• The GPE-based Li-CO2 battery demonstrated significantly improved electrochemical performance compared to conventional systems.
• The discharge product (Li2CO3) in the GPE-based battery exhibited a particle-shaped morphology with poor crystallinity.
• The battery achieved a cycle life of 60 cycles and a maximum applied current density of 500 mA g-1.

Conclusions:

• The developed GPE is effective in enhancing the performance of rechargeable Li-CO2 batteries.
• Altering the discharge product morphology through GPE is crucial for improving battery cycle life and rate capability.
• This work presents a promising strategy for developing high-performance Li-CO2 batteries.