Low-cost energy storage for stationary applications is essential to increase the use of renewable power sources.

J. F. Whitacre, Carnegie Mellon University and Aquion Energy, both Pittsburgh, PA, USA, and colleagues have developed a large-format electrochemical energy storage device. It contains an activated carbon/NaTi₂(PO₄)₃ composite anode. Blending activated carbon with NTP in a thick-format electrode, and making devices that are anode limited from a capacity perspective, results in a system that can be cycled thousands of times without significant loss in function.

The use of this composite with a λ-MnO₂-based cathode results in an energy storage device that is low cost, robust, and of sufficient energy density to be implemented in stationary applications.

• A Polyionic, Large-Format Energy Storage Device Using an Aqueous Electrolyte and Thick-Format Composite NaTi₂(PO₄)₃/Activated Carbon Negative Electrodes,
  J. F. Whitacre, S. Shanbhag, A. Mohamed, A. Polonsky, K. Carlisle, J. Gulakowski, W. Wu, C. Smith, L. Cooney, D. Blackwood, J. C. Dandrea, C. Truchot,
  Energy Technol. 2015.
  DOI: 10.1002/ente.201402127