Fig. 1

Comparison of various battery performance indicators"

Fig. 2

(a) Structure and working principle of Li/CF x primary batteries; (b) Schematic of the "core-shell" model of Li/CF x primary battery discharge; (c) Schematics of the formation of SI-CF and thus CF L product (SI-CF and COV-CF refer to the semi-ionic and covalent CF bonds, respectively), (d) Schematics for the formation and growth processes of LiF crystal nuclei and grains in solid and liquid states batteries[28]; (e) Schematic of the Li+ edge-propagation mechanism for the lithiation process of CF x[29]; (f) The schematic of the Li/CF x system mechanism through the depth of discharge[30]"

Fig. 3

(a) SEM image of fluorinated hard carbon, (b) Discharge curves of fluorinated hard carbon at different current densities, High-resolution (c) C1s and (d) F1s XPS spectra of fluorinated hard carbon[34]"

Fig. 4

(a) Schematic of the discharge of fluorinated graphite，fluorinated carbon nanotubes，fluorinated fullerenes，and fluorinated graphene; (b) Comparison of specific capacities of (CF0.25) n and FG at different current rates，SEM photographs of (c) (CF0.25) n and (d) FG； (e) Schematic representation of lithiation of fluorinated graphite polymer and fluorinated graphene[41]"

Fig. 5

(a) Schematic drawing of the plasma treatment on CF x powders (CF y denotes the highly fluorinated layer formed in the high-temperature fluorination process); (b) CF y discharge curve after modification by plasma[63]; (c) Schematic diagram of electronic paths for pristine and modified CF x during discharge; (d) Discharge curve of CF x after modification[64]"

Fig. 6

(a) Schematic representation of the synthesis of a typical conducting polymer and CF x composite cathode material; (b) TEM and HRTEM images of CF x @PTh composites with various PTh content (8.66%, 22.94%, and 33.80 %); Galvanostatic discharge curves at different rates of (c) CF x, (d) 8.66% PTh/CF x, (e) 22.94% PTh/CF x, and (f) 33.8% PTh/CF x[67]"

Fig. 7

(a) Schematic of several conductive metals compounded with CF x; (b) XRD patterns of CF x and CF x -Pt; (c) TEM images of CF x -Pt; The galvanostatic discharge curves of (d) CF x and (e) CF x -Pt[70]"

Fig. 8

(a) The schematic arrangement diagrams of four kinds of CF x -MnO2 composite cathodes with different configurations (CF x @MnO2, CF x ⊕MnO2, CF x ⊕MnO2, and CF x //MnO2), accompanied with the charge transfer mechanism in CF x //MnO2[72]; (b) Schematic of electron and lithium ion pathways for CFx and CF x @MnO2-nanowire composites; (c) Ragone plots and of pristine CF x and CF x @MnO2-nanowire composites; (d) High and low temperature discharge curves of CF x /MnO2-nanowire composites at 0.1 C[74]; (e) Schematic of the reaction mechanism between CF x and SiO2; (f) Gravimetric energy densities of various CF x -based cathodes at different current densities，and high-resolution C 1s XPS spectra of (g) CF x, (h) CF x -TEOS and (i) CF x -mSiO2[75]"

Fig. 9

(a) Schematic of the mechanism of action of BF3 additive on CF x positive electrode; Discharge curves (b) without BF3 and (c) with BF3 additive[77]"

Fig. 10

Stable adsorption configurations and adsorption energies of DMSO/1, 3 DO molecules on different LiF crystal planes[79]"

Fig. 11

Li/CF x primary batteries discharge mechanism and main optimization strategies"