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

The effects of LiPF 6 concentration in ethylene carbonate (EC)–dimethyl carbonate (DMC) on PF 6 − intercalation into graphitic carbon were studied for a high-energy-density dual-carbon battery. The capacity as well as potential for PF 6 − intercalation decreased with increasing LiPF 6 concentration when EC–DMC was used as an electrolyte. Low-viscosity carbonate was found to be suitable as a high-concentration LiPF 6 electrolyte, and DMC is thus a promising electrolyte for high-concentration LiPF 6 . The PF 6 − intercalation capacity as well as the intercalation potential in 3.7 M LiPF 6 /DMC (100 mAh g −1 ) were almost the same as those in 1 M LiPF 6 /EC–DMC (89 mAh g −1 ). Considering the anode capacity, 3.1 M LiPF 6 is suitable for the full cell. Using 3.1 M LiPF 6 in DMC, the energy density of the dual-carbon battery could be significantly increased.