Carbon nanofibers can be used to add conductive structural integrity that extends the cycle life of electrodes.
There are several unique characteristics of graphitized vapor grown carbon fibers that enhance their usefulness as constituents in electrodes of lithium-ion batteries, including:
Top table: Basic properties for submicron vapor grown carbon fibers.
Bottom left graph: Charge-discharge curve of graphitized submicron vapor grown carbon fiber batteries during the first cycle. After contact is made, the potential decreases immediately to 0.8 V and the curve shows a shoulder around 0.7 V only during the first discharge process, as is also observed in other carbon materials. The discharge capacity is 283 mAh/g, and the cycle efficiency is about 77%.
Bottom right graph: Good cyclic efficiency was observed up to above 200 cycles, possibly because of its superior bulk properties, such as higher resiliency and lower volume resistivity.
The process of graphitization involves the motion and rearrangement of carbon-layer planes. As heat-treatment temperature increase, the surface layers tend to straighten out. This process indicates that atomic rearrangement of carbon atoms is taking place within the carbon fibers.