Ultrahigh loading dry-process for solvent-free lithium-ion battery electrode fabrication

Area of Science:

• Materials Science
• Electrochemistry
• Sustainable Manufacturing

Background:

• Current lithium-ion battery (LIB) electrode fabrication relies on wet coating using N-methyl-2-pyrrolidone (NMP), an expensive and toxic solvent.
• NMP solvent requires energy-intensive drying and recycling, increasing production costs and environmental impact.
• The limitations of NMP necessitate the development of sustainable and cost-effective electrode manufacturing processes.

Purpose of the Study:

• To introduce an industrially viable and sustainable dry press-coating process for LIB electrodes.
• To evaluate the performance and mechanical properties of electrodes fabricated using the dry press-coating method.
• To demonstrate a greener alternative to conventional NMP-based wet coating techniques.

Main Methods:

• Development of a dry powder composite using multiwalled carbon nanotubes (MWNTs) and polyvinylidene fluoride (PVDF).
• Utilization of etched aluminum foil as a current collector for the dry press-coated electrodes (DPCEs).
• Fabrication and characterization of LiNi0.7Co0.1Mn0.2O2 (NCM712) electrodes using the novel dry press-coating technique.

Main Results:

• DPCEs exhibited superior mechanical strength and electrochemical performance compared to conventional slurry-coated electrodes (SCEs).
• Achieved high electrode loading of 100 mg cm⁻² (17.6 mAh cm⁻²).
• Demonstrated impressive specific energy of 360 Wh kg⁻¹ and volumetric energy density of 701 Wh L⁻¹.

Conclusions:

• The dry press-coating process is a sustainable and industrially scalable alternative for LIB electrode fabrication.
• This method significantly enhances electrode performance, mechanical integrity, and energy density.
• Eliminating NMP solvent reduces environmental impact and production costs in battery manufacturing.