It isn't. Everything described in the article is consistent with graphene supercapacitors, although the article gives no technical details about what she actually did.
It is too good to be true. It's not a graphene supercapacitor it's a H::TiO2 with a PANI core based supercapacitor, which is quite difficult to synthesize, especially mass produced. Every reagent required is considerably more expensive than a comparable Li-Ion battery. They also have a significantly lower energy, so while they may be faster to charge and have longer life spans they wouldn't fit in modern phones.