Power Electronic Enabled Active Hybrid Energy Storage System and its Economic Viability

This paper examines the technology and value proposition for the active combination of the power dense ultracapacitor with an energy optimized lithium-ion battery. Aspects of the respective technologies that can be altered for the benefit of the active parallel energy storage system are noted. Energy management control strategies are investigated that show promise for dramatic reduction in lithium-ion peak and rms currents leading to improvements in regenerative energy storage system life, efficiency, thermal performance and packaging. A new cost reduced ultracapacitor cell design is introduced and a value proposition is made showing that energy optimized lithium can "pay" for the dc-dc converter and ultracapacitors now.