Availability of grid-scale electric energy storage systems with response rates on the order of seconds plays a key role in wide implementation of renewable energy sources. Here, a new concept called the electrochemical fl ow capacitor (EFC) is presented. This new concept shares the major advantages of both supercapacitors and fl ow batteries, providing rapid charging/discharging while enabling the decoupling of the power and energy ratings. Like in supercapacitors, energy is stored in the electric double layer of charged carbon particles. A fl owable carbon-electrolyte mixture is employed as the active material for capacitive energy storage, and is handled in a similar fashion to fl ow or semi-solid batteries (i.e., for charging/discharging, it is pumped into an electrochemical cell, and for storage, it is pumped into reservoirs). This study presents the proof-of-concept of this technology and reports initial EFC performance data obtained under static and intermittent fl ow operations. Adv. Energy Mater. 2012, 2, 895-902 896 www.MaterialsViews.com www.advenergymat.de

No abstract

No abstract

No abstract

The electrochemical flow capacitor (EFC) described by E. C. Kumbur, Y. Gogotsi, and co‐workers utilizes a flowable slurry of capacitive carbon particles in an aqueous or organic electrolyte. The proposed concept combines the scalability of flow batteries with the high power density and long lifetime of electrochemical capacitors. EFC technology also decouples energy and power ratings, which is important for storage and use of energy from highly fluctuating sources. The proof‐of‐concept study presents promising initial performance data and discusses further development steps for this technology. Flow cell design by the Materials Research Center (Ukraine) and cover design by Kristy Jost (USA).