Fig. 1

(a) Schematic diagram of the reaction mechanism of rechargeable Li-Cl2 batteries; (b) Initial galvanostatic discharge curve of the Na-Cl2 battery; (c) Initial galvanostatic discharge curve of the Li-Cl2 battery; (d) Reversible galvanostatic charge-discharge curves of the Na-Cl2 battery; (e) Reversible galvanostatic charge-discharge curves of the Li-Cl2 battery"

Fig. 2

(a) TEM image of the aCNS cathode[15]; (b) Initial discharge curve of the aCNS cathode[15]; (c) Cycling performance of the aCNS cathode[15]; (d) SEM image of and DGr_ac cathode[27]; (e) Initial discharge curves of the DGr and DGr_ac cathode[27]; (f) Cycling performance of the DGr_ac cathode[27]; (g) TEM and HAADF images of the Bi-NC cathode[29]; (h) Initial galvanostatic discharge curves of the Na-Cl2 battery with bare C, NC and Bi-NC[29]; (i) Cycling performance of the Na-Cl2 battery with bare C, NC and Bi-NC[29]"

Fig. 3

(a) Reaction mechanism graph of the UiO-66-NH2 cathode[30]; (b) Charge/discharge curves for different cut-off capacity of UiO-66-NH2[30]; (c) Structure of COF-NH2[31]; (d) COF-NH2 assembled battery working diagram[31]; (e) Crystal structure of the CC3-POC[32]; (f) Chlorine adsorption by CC3-POC[32]; (g) Cycling performance graph of CC3-POC assembled battery at -20 ℃[32]"

Fig. 4

(a) Performance comparison chart of different cathode materials in terms of first discharge capacity, maximal reversible capacity, maximal cycle number, specific surface area, maximal current density and operating temperature; (b) Comparison diagram of first discharge capacity of different cathode materials; (c) Comparison diagram of surface area of different cathode materials"

Fig. 5

(a) Schematic diagram of the reaction mechanism in the electrolyte system of LiAlCl4, SOCl2 and I2[33]; (b) Optical diagrams of the reaction between SOCl2 and H2O with and without DCE and optical diagrams of lithium metal immersed in SOCl2 with and without DCE for 3 days[34]"

Fig. 6

(a) Schematic diagram of Li metal and Li-Si alloy surfaces after cycling[34]; (b) Comparison of Li metal and Li-Si alloy anodes in terms of discharge voltage, energy density, multiplier performance, cost and safety[34]; (c) SEM image of Li metal after 20 cycles[34]; (d) SEM image of Li-Si metal after 20 cycles[34]"