A Prussian Blue-Derived Dual-Functional Precursor for High-Performance LFP/C Cathodes

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Olivine lithium iron phosphate (LFP) is a promising cathode material for lithium-ion batteries due to its safety and environmental benefits.
• However, LFP suffers from poor electrical conductivity and slow lithium-ion transport, limiting its use in high-power applications.

Purpose of the Study:

• To develop a novel, efficient method for synthesizing carbon-coated LFP (LFP/C) with enhanced electrochemical performance.
• To utilize Prussian blue (PB) as a dual-functional precursor for both iron and carbon sources in a one-step process.

Main Methods:

• A one-step sintering process was employed using Prussian blue (PB) as a precursor to synthesize carbon-coated LFP (LFP/C).
• Electrochemical evaluations, including discharge capacity, rate performance, and long-term cycling stability tests, were conducted.

Main Results:

• The synthesized LFP/C exhibited an initial discharge capacity of 160.3 mAh·g^-1 at 0.2C, with excellent retention (119.1 mAh·g^-1 at 6C) and capacity rebound.
• Exceptional long-term cycling stability was demonstrated, with 96.7% and 84.3% capacity retention after 500 cycles at 1C and 5C, respectively.
• The performance improvements are attributed to an in situ formed carbon layer and a highly ordered structure derived from the PB precursor.

Conclusions:

• Prussian blue serves as an effective dual-functional precursor for synthesizing high-performance LFP/C materials.
• This approach offers a straightforward and efficient pathway for developing advanced LFP/C cathodes for high-power lithium-ion batteries.