Dual-Carbon Battery Using High Concentration LiPF6in Dimethyl Carbonate (DMC) Electrolyte

The effects of LiPF6 concentration in ethylene carbonate (EC)–dimethyl carbonate (DMC) on PF6− intercalation into graphitic carbon were studied for a high-energy-density dual-carbon battery. The capacity as well as potential for PF6− intercalation decreased with increasing LiPF6 concentration when EC–DMC was used as an electrolyte. Low-viscosity carbonate was found to be suitable as a high-concentration LiPF6 electrolyte, and DMC is thus a promising electrolyte for high-concentration LiPF6. The PF6− intercalation capacity as well as the intercalation potential in 3.7 M LiPF6/DMC (100 mAh g−1) were almost the same as those in 1 M LiPF6/EC–DMC (89 mAh g−1). Considering the anode capacity, 3.1 M LiPF6 is suitable for the full cell. Using 3.1 M LiPF6 in DMC, the energy density of the dual-carbon battery could be significantly increased.