STTR Phase I: Supercapacitors for Power Supplies

The broader impact/commercial potential of this project is the first time commercial development of a copper cable which can transmit and store energy. Currently, copper cables are used for transmitting electricity. Adding energy storage capability to these cables is transformative and has the potential to be employed in a myriad of electrical and electronic applications. Making these cables into spools of wires and custom sliced into a certain length to achieve a required capacitance will be very attractive to commercial applications. The proposed study enables to understand how energy transmission and storage can be simultaneously performed without mutual interference. These cables can find niche applications in the automotive, energy, defense, and IT industries. Moreover, when made into thin wires, it can be weaved into a matrix which can be used to charge wearable devices. For example, currently, a soldier carries about 30-40 pounds of battery for a three-day mission. However, if energy storage devices like the one proposed here can be made into an advanced textile form and can be worn as a uniform, the weight currently carried by the soldiers can be considerably reduced. A cable energy storage device developed can also be beneficial for storing energy for clean-energy technologies such as wind and solar. This Small Business Technology Transfer (STTR) Phase I project fills the gap of a cable-type capacitor which saves space and fits well with electrical and electronic devices. The objective of this proposal is to use nanotechnology-based fabrication techniques to grow nanowhiskers with a high surface area on a copper cable to make cable-type capacitors. These nanostructures considerably enhance the surface area necessary for the storage of electrical charges. Since nanostructures are developed only on the outside of the electrical cable to store energy, the inner part of the cable can still be used for electrical transmission. The focus of the proposed research is to develop the processes which can be used to make these nanostructured electrodes into a cable capacitor. The fabrication techniques for growing nanostructures will be so designed that making long lengths of the cables are feasible. The performance of the cable-based capacitors will be tested in terms of capacitance, cycle life, voltage output, etc. In addition, the flexibility of the cable will be tested at different bend-angles to evaluate its applications in flexible energy storage applications.