Tailoring the Interfacial Behavior to Stabilize Iron Oxalate Anode for Boosting Ultrahigh Lithium Storage

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Iron (II) oxalate is a promising anode material for lithium-ion batteries due to its low cost and high capacity.
• Poor electronic conductivity and active material loss during cycling limit its performance.

Purpose of the Study:

• To develop a surface functionalization strategy for iron (II) oxalate to improve lithium storage performance.
• To mitigate active component loss and enhance stability during battery cycling.

Main Methods:

• Surface functionalization of iron (II) oxalate using carbonized carboxymethyl cellulose (CMC).
• Generation of a carbon layer enriched with carbonyl functional groups.
• Analysis of the effect of the carbon layer on SEI formation and reaction intermediates.

Main Results:

• The optimized composite exhibits a high reversible capacity of 1652 mAh g^-1 at 0.5 A g^-1.
• A capacity of 517 mAh g^-1 is retained at an ultrahigh current density of 15 A g^-1.
• The carbonyl-rich layer effectively regulates SEI formation and improves adsorption of reaction intermediates.

Conclusions:

• The proposed surface functionalization strategy significantly enhances the lithium storage capability of iron oxalate.
• This approach provides a general method for improving oxalate-based materials for electrochemical energy storage.