▎ 摘 要
We report experimental evidence for the specific Li-storage at turbostratic graphene edges of a well-known and cheap Super 1D carbon black (Csp) material, which is usually used as a conductive additive in composite electrodes. Indeed, operand XRD and HR-TEM consistently demonstrate Li insertion occurs with zero expansion of graphene layer up to a composition of Li0.4C6 (150 inA h/g) that is reached at 0.01 V vs. Li+/Li. Li-7 NMR substantiates these results and suggests that the weak electronic transfer from the carbon host to the intercalant could help local reorganization of the layer order as suggested by the unexpected reversible changes of the (002) Bragg peak intensity during the charge-discharge process. Our observations also indicate this insertion mechanism is kinetically favored resulting in remarkable cycling stability over 1000 cycles and power capability allowing to sustain 110 inA h/g at 8 A/g (21 C) in half cell. The capability of Csp as an efficient anode is ultimately demonstrated in a lithium hybrid capacitor against a positive electrode of activated carbon, The full cell delivers a maximum energy of 120 Wh/kg (4.3-2 V) and remarkable capacity retention over 1800 cycles.