Surface fluorination and electrochemical behavior of petroleum cokes graphitized at medium and high temperatures for secondary lithium battery

Surface modification of carbon anodes for secondary lithium battery by fluorination

“…Potential curves for original petroleum coke (PC) gradually decreased and increased with intercalation and deintercalation of lithium ion, respectively. However, the profile of potential curves for petroleum cokes heat-treated at 2100-2800 8C was rather similar to that for natural graphite [11][12][13]. First coulombic efficiencies of non-fluorinated petroleum cokes varied depending on the heat-treatment temperatures, that is, the crystallinity of petroleum coke samples.…”

“…The larger discharge capacities than the theoretical value of graphite, 372 mAh/g were obtained for surface-fluorinated graphite samples [6][7][8][9][10]. Since synthetic graphites are often used as anodes of secondary lithium batteries, petroleum coke and those heat-treated at 1860-2800 8C were fluorinated by F 2 , ClF 3 and NF 3 and their surface structure changes and electrochemical behavior were recently investigated [11][12][13]26]. The present paper summarizes the results recently obtained for the petroleum coke samples.…”

“…Some methods of surface modification have been already applied. They are surface oxidation [3][4][5], surface fluorination [6][7][8][9][10][11][12][13][14][15], metal or metal oxide coating [16][17][18][19] and carbon coating [20][21][22][23][24][25]. It has been shown that surface fluorination increases the discharge capacities of natural graphite samples with different particle sizes [6][7][8][9][10].…”

Electrochemical cell studies on fluorinated natural graphite in propylene carbonate electrolyte with difluoromethyl acetate (MFA) additive for low temperature lithium battery application

“…Some effective methods are, surface fluorination, surface oxidation, metal coating, carbon coating, polymer coating…etc. [6][7][8][9][10][11][12] Surface fluorination is one of the most effective way to modify the surface. Some selective enhancements by surface fluorinations are surface disorder, reaction kinetics, mesopore's expansion of graphite material, which can accommodate more lithium ions, surface area and decomposition potential shift.…”

Direct fluorination of Twaron fiber and investigation of mechanical thermal and morphological properties of high density polyethylene and Twaron fiber composites

“…[16][17][18][19][20][21] Direct fluorination and oxy-fluorination have emerged a premier physicochemical surface modification technique, as this process does not need any initiation proceeding at practically appreciable rates at ambient temperatures for exothermic nature of this reaction. Fluorinated polymers possess a set of unique properties such as enhanced mechanical properties, thermal stability, good barrier and membrane properties, printability, and adherence properties.…”