(53e) Effects of Nanocarbon Buffer Layers On the Anodic Performance of Copper Oxide and Ball-Milled Graphite Composites

Graphite has been used as an anode active material in lithium ion batteries (LIBs) owing to its stable reversibility for a long cycle life, despite of its low capacity (372 mAh g^-1). In order to increase capacity in LIB, tremendous research works have recently given to high capacity 3d metal oxides (MOs) such as Co₃O₄, CuO, NiO, and Fe₂O₃. However, these metal oxides undergo a significant volumetric change during charge/discharge processes, leading to materials pulverizations and ultimately rapid electrode degradation. The MOs were anchored on two-dimensional graphene sheets or on one-dimensional carbon nanotubes (CNTs) to alleviate volume expansion and the agglomeration of MO particles. However, CNT and graphene supports are easily aggregated in electrode manufacturing processes. They also have high irreversible capacities due to the formation of solid electrolyte interface (SEI) film on their large surfaces. Unfortunately, detailed investigations of nanocarbons (graphene or CNT) as buffer layers in anodes have not been performed.

In this presentation, nanocarbon papers will be thoroughly compared as buffers for the volume changes of nano-sized CuO/ball-milled graphite (BMG). Morphological and electrochemical characterization techniques will be used for comparison. In addition, the van der Waals forces between CNT layers or graphene layers will be theoretically calculated and their effect on the performance of the buffer layers will be discussed.