fig5

Figure 5. (A) Crystal structures of tavotite and triplite-type LiFeSO₄F and triplite-type type NaFeSO₄F. This figure is quoted with permission from Ati et al.^[59]. and Tripathi et al.^[60]. (B) The tavorite LiFeSO₄F has a stable cycling performance. Charge/discharge profile of LiFeSO₄F cells cycled between 2.5 and 4.2 V at 15 mA g^-1. This figure is quoted with permission from Recham et al.^[61]. (C) Charge and discharge profiles for triplite-type NaFeSO₄F discharge at 0.01 C (1C = 138 mA g^-1). This figure is quoted with permission from Kim et al.^[62]. (D) a-LiFeSO₄F shows a different charge/discharge mechanism compared to tavotite and triplite-type LiFeSO₄F. dQ/dV profile of a-LiFeSO₄F (blue), tavorite (green), and triplite (orange). This figure is quoted with permission from Heo et al.^[64]. (E) Cycling performance of a-LiFeSO₄F at different temperatures measured at a current density of 40 mA g^-1. This figure is quoted with permission from Heo et al.^[64].