title: Photothermally reduced graphene as high-power anodes for lithium-ion batteries.
abstract: Conventional graphitic anodes in lithium-ion batteries cannot provide high-power densities due to slow diffusivity of lithium ions in the bulk electrode material. Here we report photoflash and laser-reduced free-standing graphene paper as high-rate capable anodes for lithium-ion batteries. Photothermal reduction of graphene oxide yields an expanded structure with micrometer-scale pores, cracks, and intersheet voids. This open-pore structure enables access to the underlying sheets of graphene for lithium ions and facilitates efficient intercalation kinetics even at ultrafast charge/discharge rates of >100 C. Importantly, photothermally reduced graphene anodes are structurally robust and display outstanding stability and cycling ability. At charge/discharge rates of ~40 C, photoreduced graphene anodes delivered a steady capacity of ~156 mAh/g(anode) continuously over 1000 charge/discharge cycles, providing a stable power density of ~10 kW/kg(anode). Such electrodes are envisioned to be mass scalable with relatively simple and low-cost fabrication procedures, thereby providing a clear pathway toward commercialization.
authors.affiliation: Department of Mechanical, Rensselaer Polytechnic Institute, Troy, New York 12180, United States.
authors.forename: Rahul
authors.initials: R
authors.lastname: Mukherjee
authors.forename: Abhay Varghese
authors.initials: AV
authors.lastname: Thomas
authors.forename: Ajay
authors.initials: A
authors.lastname: Krishnamurthy
authors.forename: Nikhil
authors.initials: N
authors.lastname: Koratkar
mesh_terms: D011211:Electric Power Supplies; D004566:Electrodes; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite / Q000737:chemistry* / Q000528:radiation effects; D006358:Hot Temperature; D008027:Light; D008094:Lithium / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010084:Oxidation-Reduction / Q000528:radiation effects
chemical_list: D006108:Graphite; D008094:Lithium