Lithium super-battery with a functionalized nano graphene cathode

摘要

An electrochemical energy storage device, lithium super-battery, comprising a positive electrode, a negative electrode, a porous separator disposed between the two electrodes, and a lithium-containing electrolyte in physical contact with the two electrodes, wherein the positive electrode comprises a plurality of chemically functionalized nano graphene platelets (f-NGP) or exfoliated graphite having a functional group that reversibly reacts with a lithium atom or ion. In a preferred embodiment, a lithium super-battery having a f-NGP positive electrode and Li4Ti5O12 negative electrode exhibits a gravimetric energy ˜5 times higher than conventional supercapacitors and a power density ˜10 times higher than conventional lithium-ion batteries. This device has the best properties of both the lithium ion battery and the supercapacitor.

主权项

1. A lithium super-battery or lithium-exchanging battery device comprising a positive electrode, a negative electrode, a porous separator disposed between the two electrodes, and a lithium-containing electrolyte in physical contact with the two electrodes, wherein the positive electrode comprises a plurality of chemically functionalized nano graphene platelets or exfoliated graphite having a functional group that reversibly reacts with a lithium atom or ion wherein said nano graphene platelets or exfoliated graphite contain an oxygen amount of at least 1% by weight or have a platelet less than 10 nm in thickness or having no greater than 20 graphene planes.