: A flexible, light weight and high conductivity current collector is the key
element that enables fabrication of high performance flexible lithium ion battery. Here
we report a thin, light weight and flexible lithium ion battery that uses graphite paper
enhanced with a nano-sized metallic layers as the current collector, LiFePO4 and
Li4Ti5O12 as the cathode and anode materials, and PE membrane soaked in LiPF6 as a
separator. Using thin and flexible graphite paper as a substrate for the current collector
instead of a rigid and heavy metal foil enables us to demonstrate a very thin LithiumIon
Battery into ultra-thin (total thickness including encapsulation layers of less than
250 μm) that is also light weight and highly flexible.