High–Power Electrodes for Lithium-Ion Batteries

For novel 3-D anodes made of sheets of carbon (graphene) and silicon nanoparticles, transport studies found much shorter lithium diffusion paths throughout the electrode and fast lithiation/delithiation of the nanoparticles.

This anode design holds a greater charge than conventional lithium-ion anodes and charges/discharges more rapidly while maintaining mechanical stability.

• Electrochemical studies: 83% of theoretical capacity (3200 mAh g^-1) retained after 150 charge/discharge cycles at high power (1 A g ^-1).
• Anode material is prepared by a process expected to be scalable to commercial quantities.

3-D graphenic scaffold with in-plane defects and Si nanoparticles between sheets: A novel method of synthesis creates an anode with a stable structure of holey graphene layers propped up by intermixed Si nanoparticles

Reference: Xin Zhao, Cary M. Hayner, Mayfair C. Kung, and Harold Kung, In-Plane Vacancy-Enabled High-Power Si-Graphene Composite Electrode for Lithium-Ion Batteries, Adv. Energy Mater., 1, 1079-1084 (2011) [DOI: 10.1021/ja200595f].

Support: Work was performed at Northwestern University and supported by the Center for Electrical Energy Storage (CEES),an EFRC led by Michael Thackeray at Argonne National Laboratory.