This proposal discusses a novel approach to drastically reduce the interface resistance at the collector metal-electrode material interface which normally is the dominant component in the equivalent series resistance. When the resistance is high, the power performance is poor. We grow multiwalled carbon nanotubes (MWCNTs) in tower-like structures directly on metal alloy substrates without any catalyst or binder material to prepare the electrode. Other innovations include a plasma-based clean and efficient treatment to eliminate any oxygen functional groups which add to the resistance. Phase I project will provide design guidelines to achieve the metrics set forth by the Air Force and also include construction of a test cell to provide preliminary measurements demonstrating the concepts proposed in this innovation.
Benefit: Ultracapacitors find numerous applications where high power and long cycle life are needed but not met by conventional batteries. These include electric/hybrid vehicles, cold-starting assistance, catalytic converter preheating, delivery vans (FedEx, others) with a lot of stop and go routines, golf carts, go-carts, cell phones, PDAs, pagers, UPS (uninterruptible power supply) for computers, standby power systems, copy machines (speeding of warmup mode, minimizing standby mode), car stereo amplifiers, and many others.
Keywords: Ultracapacitors, Supercapacitor, Multiwall Carbon Nanotube, Tower Electrodes, Metal Alloysubstrate, Plasma-Based Cleaning, Long Cycle Life.
