Electrochemical behavior of surface-modified petroleum cokes in propylene carbonate containing solvents

Surface modification of carbon anodes for secondary lithium battery by fluorination

“…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.…”

“…The increase in the first discharge capacities was mainly observed for many PC1860, PC2300 and PC2800 samples fluorinated by ClF 3 and NF 3 as given in Table 8 [26]. Surface fluorination increased the first discharge capacities by $52 mAh/ g ($24.0%) and $63 mAh/g ($29.6%) at 150 mA/g for PC2300 and PC2800, respectively.…”

“…Fluorination mechanism by ClF 3 and NF 3 is different from that by F 2 because no surface fluorine was detected by XPS except one sample as given in Table 6 [26]. In addition, small amounts of chlorine were detected in the samples fluorinated by ClF 3 .…”

“…3) [27]. PC2800 fluorinated by ClF 3 and NF 3 show etched surface and opened edge [26]. The closed edge surface was thus destroyed and opened with carbon-carbon bond rupture.…”

Surface Modification of Carbon Anodes for Lithium Ion Batteries by Fluorine and Chlorine

“…They are carbon coating [1][2][3][4][5][6][7][8][9][10][11][12][13][14], metal or metal oxide coating [15][16][17][18][19][20][21][22][23][24][25], surface oxidation [26][27][28][29][30][31][32][33], surface fluorination and chlorination [34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52], and polymer, Si or Sb coating …”