Exploring Propylene Carbonate as a Green Solvent for Sustainable Lithium-Ion Battery Cathode Manufacturing

Abstract

This study pioneers the use of propylene carbonate (PC) as a green solvent alternative to N-methyl-2-pyrrolidone (NMP) for Li-ion battery cathode manufacturing, addressing a critical gap in sustainable electrode fabrication. Unlike prior research focused on half-cell evaluations of alternative solvents, this work uniquely extends to both half-cell and full-cell configurations across multiple cathode chemistries, offering a comprehensive assessment of PC's viability. Electrodes prepared using PC exhibit comparable coating quality and morphological characteristics, including uniform particle distribution and structural integrity, to NMP-processed counterparts. Electrochemical assessments indicate that PC-based electrodes provide superior first-cycle Coulombic efficiency and closely match the electrochemical performance of NMP electrodes at lower active material (AM) loadings, including stable capacity retention and minimal polarization even at higher C-rates. However, at higher AM loadings, the PC-based electrode exhibits increased interfacial and contact resistance, possibly due to incomplete PC solvent removal, leading to reduced capacity retention and increased polarization at higher C-rates. These limitations suggest that while PC is a promising sustainable alternative, its practical application requires further optimization, including refining drying processes to enhance solvent removal and interfacility stability.