Electrochemical behavior of surface-fluorinated graphite

Surface fluorination of the cathode active materials for lithium secondary battery

“…In contrast, the M-F bond is unable to be attacked by HF and hence the www.elsevier.com/locate/fluor Journal of Fluorine Chemistry 125 (2004) 1657-1661 active materials having the fluorinated surface are expected to be stable in the electrolyte solution containing LiPF 6 . Several papers on the fluorination of anode carbon materials reported that both the hydrophilic and hydrophobic surfaces can be generated by fluorination under the controlled conditions [12][13][14]. In our previous papers, it was reported that fluorine is introduced to the surface of metal oxides by the reactions with NF 3 , ClF 3 , etc.…”

Green Fluorination of Natural Graphite and its Application in Rechargeable Magnesium Ion Transfer Battery

“…The surface area of the electrode material is increased, with a subsequent increase of metal-ion intercalation and/or adsorption in the electrode. This latter property may be due to two factors: (i) an increase in the structural disorder caused by fluorination which probably diminishes the length of the graphitic domains and induces the formation of surface nanopores in which excess metal can be accommodated.Graphite fluorides have been studied as cathode materials in lithium 5-8 or aluminum batteries 9 Nakajima et al 10 had shown that a low fluorination of graphite can improve the capacitance of C-F in Li battery system during the insertion into the resulting materials in comparison with graphite. As a matter of fact the treated graphite samples, which contain small amounts of fluorine (0.5-3.7 atom %), exhibit discharge capacities of about 380 mAh/g.…”

Performance enhancement of spherical natural graphite by phenol resin in lithium ion batteries

“…A larger R-value shows that the D-band intensity is more obvious with the added phenol resin. This is a standard index of the amount of carbon coating [20][21][22]. This picture demonstrates that the R-value is 0.07 when the phenol resin approaches 10 wt%.…”

“…Therefore, the surface modification of spherical graphite has recently become a subject of research. For instance, graphite is mildly oxidized by catalytic oxidation [1][2][3], air [4][5][6], oxygen, carbon dioxide [7], solution of H 2 O 2 , Ce(SO 4 ) 2 [8,9], or fluorinated by fluorine gas [10][11][12]. It has other uses, such as epoxy resin coating [13], ionic conductive copolymer [14], oxidative solutions [15,16], silver deposition [17] or mechanical milling [18].…”