A comparative study of polyacrylic acid and poly(vinylidene difluoride) binders for spherical natural graphite/LiFePO4 electrodes and cells

摘要: Abstract Anodes containing spherical natural graphite (SNG12) and cathodes LiFePO4, both from HydroQuebec, were prepared with aqueous-based polyacrylic acid (PAAH), its neutralized derivatives (PAAX) (X = Li, Na, K), conventional poly(vinylidene difluoride) (PVDF) binders. A comparison of electrode performance was made between these three binder systems. The electrodes optimized by adding elastic styrene butadiene rubber (SBR) conductive vapor grown carbon fiber (VGCF) in the place some PAAX. Initially, SNG12 LiFePO4 characterized half cells Li as counter electrode. electrochemistry results show that use PAAX binders can significantly improve initial coulombic efficiency, reversible capacity, cyclability anodes compared to based on a PVDF binder. By using an composition for anode cathode, SNG12/LiFePO4 full PAALi cycled 847 times 70% capacity retention, which significant improvement over (223 cycles). This study demonstrates possibility manufacturing Li-ion batteries cycle longer water processing, instead hazardous organic solvents like NMP, thereby improving performance, reducing cost, protecting environment.