Carbon-based supercapacitors (SCs) have limited energy density due to sluggish mass diffusion and restricted charge accumulation. To increase the energy density of carbon-based SCs

attention must be paid to the factors of specific capacitance and electrochemical stability window. This review summarizes recent signs of progress in carbon-based materials

including specific surface area

pore structure regulation

heteroatom doped

and carbon composites. In addition

we discuss aqueous

organic

and ionic liquid electrolytes that affect the electrochemical stability window of SCs. Finally

the possibilities for achieving synergy in electrode/electrolytes are summarized via enhancing the pseudocapacitance contribution and developing high-voltage window electrolytes.