凯发

Energy conversion and storage are two of the grand challenges that our society is facing. New materials and processes can improve the performance of existing devices or enable new ones that are also environmentally benign. In this talk we will start by reviewing recent progresses on the large-scale production of graphene, two-dimensional crystals and related composites for industrial applications. We will then focus on energy conversion and storage and, particularly, on our recent developments of graphene-based ink battery that displays an estimated energy density of about 200 Whkg-1 and a stable operation for over 80 charge-discharge cycles. These properties are linked to the graphene nanoflake anode displaying crystalline order and high uptake of lithium at the edges. We also discuss the role of the graphene nanoflake morphology on the mechanism of lithium uptake highlighting the impact of the number of graphene layers and nanoflake lateral sizes on irreversible/reversible capacities. Our approach, compatible with any printing technologies, is cheap and scalable and opens up new opportunities for the development of high-capacity Li-ion batteries.