May 12 2017
A recent research reveals that in a battery system, electrodes containing porous graphene scaffolding deliver a considerable improvement in both the retention and transport of energy. Typically, methods to increase the density of stored charge conflict with those that aim to enhance the speed at which ions can travel through a material.
Nanostructured materials have displayed surprising potential for electrochemical energy storage, but these materials are generally restricted to laboratory cells with ultrathin electrodes and very low mass loadings. Hongtao Sun overcame this difficulty by adding holey graphene into a niobium pentoxide electrode. The nanopores enable fast ion transport. By "fine-tuning" the size of the nanopores, the researchers were able to accomplish high mass loading and better power capability, while still sustaining the higher charge transport.
An unprecedented combination of high areal capacity and current density at practical mass loadings (10 to 20 mg cm-2) marks a critical step toward the use of high-performance electrode materials in commercial cells.
Hui-Ming Cheng and Feng Li
Source: http://www.aaas.org