Abstract：Multiwalled carbon nanotubes(MWCNTs) were fluorinated to get the material of MWCNTs fluoride with different atomic ratio. The ratio of fluorine and carbon was 0.28(CF0.28), 0.56(CF0.56) and 0.78(CF0.78) respectively. The fluoride MWCNTs were used as cathode active material to coat on aluminum foil, lithium metal foil as counter electrode in Li/CFx batteries. The structures and properties were characterized by thermal gravimetric analyzer(TGA), scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction(XRD), and X-ray photoelectron spectroscopy(XPS). The electrochemical performance was tested by galvanostatic discharge test. The results show that the battery with CF0.78 has the best electrochemical performance. At the current density of 39mA/g, the battery displays high discharge specific capacity of 724mAh/g and appears with a more stable platform for the discharge process. At the current discharge rate of 0.05C, the utilization of three kinds of MWCNTs fluoride electrodes is 73.4%, 89.6%, 92.9%. When the discharge rate is 2C, batteries with three different MWCNTs fluoride have discharge specific capacity attenuation rate of 68.8%, 34.1%, and 39.6%. It indicates that the discharge specific capacity attenuation rate can be mitigated to a certain extent with the improved level of fluoridation. Although the discharge capacity attenuation rate of CF0.78 is higher than that of CF0.56, CF0.78 has the most stable discharge curve at the same discharge rate.
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