Paper-based composite separator for high-rate lithium-ion batteries application by highly-connected pore structure...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Accelerating charging speed is crucial for lithium-ion battery (LIB) applications.
• Separator design presents challenges for fast lithium-ion flux during high-rate battery operation.

Purpose of the Study:

• To design a highly-connected pore structure for LIB separators to enhance fast-charging capabilities.
• To develop a novel paper-based composite separator using bagasse pulp and Al2O3 nanoparticles.

Main Methods:

• Fabrication of a composite separator by blending bagasse pulp with Al2O3 nanoparticles.
• Reverse-coating with polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) for particle adhesion.
• Characterization of pore structure using multi-range X-ray nano-computed tomography (CT).

Main Results:

• The composite separator exhibited a highly connected pore structure with an average of 8 throats per pore and a pore-to-throat ratio of 2.32.
• Al2O3 nanoparticle coating promoted homogeneous Li+ ion deposition.
• The assembled LIB showed good fast-charging performance with 88% capacity retention after 2000 cycles.

Conclusions:

• The developed separator design offers a novel approach for enhancing fast-charge LIB applications.
• Highly connected pore structures are beneficial for fast lithium-ion flux and battery performance.
• The composite separator demonstrates potential for improving LIB charging speeds and cycle life.