The Effect of Commercialized Binders on Silicon Oxide Anode Material for High Capacity Lithium ion Batteries

The lithium insertion/extraction properties of silicon oxide (SiO x ) composite electrode are investigated using polyvinylidene fluoride (PVDF), LA132 (which major copolymerization chain is polyacrylonitrile-polyacrylic acid (PAN-PAA)) and polyacrylic acid (PAA). Electrochemical cycling tests show that SiO x electrode with conventional binder PVDF results in rapid capacity fading, while aqueous binders LA132 and PAA remarkably improve the cycle performance of SiO x at a current density of 80 mA·g -1 . SiO x electrode with PAA delivers a reversible capacity up to 1090 mAh·g -1 after 50 cycles. All of the electrodes after 10 cycles exhibiting a huge expansion of surface morphology, and some crevices are observed in SiO x -PVDF electrode. Results of Fourier Transform Infrared Spectroscopy (FTIR) and X-ray diffraction (XRD) show that amorphous or little crystalline grain structure and ester-like bonds are the key factors of adhesion property for binders in SiO x composite electrode. With cycling, impendence of the SiO x electrodes with different binders is increasing severely. In addition, the differential capacity plots are used to explain the capacity fading mechanism, the kinetics of electrode process of SiO x are not affected by applying different binders.