The Extreme Hybrid™ technology represents a groundbreaking advancement in plug-in hybrid vehicle drivetrains. Unlike conventional hybrids, which rely solely on lithium-ion batteries, the Extreme Hybrid™ utilizes a unique two-part energy storage system combining lithium-ion batteries with ultracapacitors. This innovative approach maximizes the benefits of both technologies: lithium-ion batteries offer high energy density but are prone to deep discharges, while ultracapacitors provide high power density and cycle life.
By integrating ultracapacitors into the system, the Extreme Hybrid™ achieves rapid acceleration and top speeds in electric-only mode, comparable to conventional hybrids. This design also allows for a smaller internal combustion engine while maintaining high vehicle performance. For daily commutes of up to 40 miles round trip, the Extreme Hybrid™ operates entirely on electric power, without utilizing its internal combustion engine.
The Extreme Hybrid™ drivetrain consists of five primary subsystems: advanced lithium batteries recharged from the grid at night, Fast Energy Storage™ utilizing ultracapacitors for acceleration and regenerative braking, advanced power electronics and control software, an internal combustion engine, and electric traction motors and generators. The result is an impressive fuel efficiency of 150 miles per petroleum gallon (MPPG) for the XH-150™ plug-in hybrid SUV.
One key difference between the Extreme Hybrid™ and conventional hybrids lies in the increased battery capacity and the ability to recharge from the electric grid. Additionally, the presence of a second Fast Energy Storage™ component enables rapid acceleration and enhanced regenerative braking capability.
AFS Trinity selected lithium-ion battery technology for its lightweight and high energy storage capacity. To mitigate battery life concerns due to high current discharges, ultracapacitors buffer the battery, extending its lifespan to a remarkable ten years or 150,000 miles in an Extreme Hybrid™ SUV. The advancement of battery and power electronics technologies, coupled with decreasing prices, contributes to the affordability and viability of Extreme Hybrid™ vehicles, expected to reach maturity by 2010.