Niranjanmurthi Lingappan, Lingxi Kong and Michael G. Pecht
Center for Advanced Life Cycle Engineering, University of Maryland, College Park, MD 20742, USA
The demand for safer and cost-effective lithium-ion batteries with higher energy density and longer life requires thorough investigation into the structural and electrochemical behavior of cell components. Binders are a key component in an electrochemical cell that function to interconnect the active material and conductive additive and adhere firmly to the current collector. The characteristic changes in binders during device operation can result in desquamation of active materials from the current collector and induce capacity degradation. Here we provide a comprehensive evaluation of the pros and cons of the traditional polyvinylidene fluoride (PVDF) binder, the correlation between PVDF and capacity loss, and the research progress of aqueous-based binders. Although aqueous-based slurry technology has spurred widespread interest across myriad topics, the purpose of this study is to examine whether aqueous binders can facilitate breakthroughs in future battery technology from the commercialization perspective. By critically analyzing the electrochemical performance of commercially viable anodes and cathodes, we address the key advantages as well as disadvantages of aqueous-based binders. Although aqueous binders outperform the low expandable graphite anode and metal oxide cathodes, their efficiency for largely expandable silicon anodes is unsatisfactory. Thus, aggressive effort is required to develop high-performance binders for future battery technology.