A High Power Electrochemical Double Layer Capacitor for Hybrid Operations

Feasibility of double layer capacitors (DLC) utilizing two types of molten salts as electrolytes will be investigated. These double layer capacitors involve two high surface area carbon electrodes, a separator and molten salt electrolytes. They will operate in the range of temperatures from room temperature to 260oC. A high single cell voltage and low cell resistance are anticipated for these double layer capacitors; a high energy density and power are also expected. A single cell voltage as high as 4.4 V is expected for one type of DLC. Energy density calculated for one of the DLC's is 4 times greater than for the C/H2SO4/C capacitor; the maximum power achieved will also be 4 times greater. A prototype of the capacitor will be designed, built and evaluated during the Phase I program. Anticipated Benefits: These capacitors may be utilized in a variety of applications demanding a high power and a high energy density including the hybrid systems for electric traction.