Enhanced energy storage performance in polyetherimide composites via oriented one-dimensional BZCT@BT core-shell...

Area of Science:

• Materials Science
• Electrical Engineering
• Polymer Science

Background:

• High voltage and high power density dielectric capacitors require materials with superior insulation and energy storage capabilities.
• Existing polymer dielectrics often face limitations in achieving optimal performance due to dielectric mismatch and breakdown strength issues.

Purpose of the Study:

• To construct a novel polymer dielectric composite for enhanced energy storage performance.
• To investigate the effects of calcium barium zirconate titanate (BZCT) and barium titanate fiber (BT) fillers on polyetherimide (PEI) matrix properties.

Main Methods:

• Fabrication of a polymer dielectric composite using polyetherimide (PEI) as the matrix and a composite filler of calcium barium zirconate titanate coated by barium titanate fiber (BZCT@BT).
• Systematic variation of BZCT@BT filler content (0.5%-10%) within the PEI matrix.
• Characterization of dielectric properties, including discharge energy density (Ue) and charge/discharge efficiency (η), and breakdown strength.

Main Results:

• The optimized (0.5% BT, 10% BZCT@BT/PEI) composite achieved a discharge energy density (Ue) of 6.66 J/cm³ and a charge/discharge efficiency (η) of 93.29%.
• BZCT addition increased the relative dielectric constant (εr), while BT addition mitigated electric field distortion caused by dielectric mismatch.
• Oriented fiber fillers significantly enhanced the breakdown strength of the polymer dielectric.

Conclusions:

• The developed BZCT@BT/PEI polymer dielectric composite demonstrates excellent energy storage performance.
• The composite offers a promising new strategy for designing high-performance energy storage polymer dielectrics.
• The synergistic effect of BZCT and BT fillers, along with oriented fiber structure, is crucial for improved dielectric and energy storage characteristics.