Photo of ultracapacitor
Capturing and conserving kinetic energy as regen during vehicle deceleration is the sole contributor to energy used for the hybrid motor boost. No plug-in or engine assisted charging is used.
In applications with a start / stop intensive duty cycles, a deceleration from 30-35 mph to zero is completed in only 12-14 seconds. If the hybrid cannot store this quick burst of energy, hybrid efficiency and the resulting fuel and emissions savings are lost. Likewise, if sufficient amps are not available for boost torque ahead of the engine and transmission during launch, hybrid savings will be minimized.
Our research has found that even high technology batteries are deficient in both of these areas.
To achieve the most efficient hybrid to capture and conserve this deceleration energy, the VTM hybrid uses ultracapacitor energy storage instead of batteries.
Because the ultracapacitor avoids the electrical to chemical conversion required by batteries, rapid bursts of high amps can be readily stored during the regen cycle. Conversely, the available high amps in the ultracapacitor are instantly converted to launch torque to boost vehicle acceleration when torque converter slip is high and engine efficiency is at a minimum. The ultracapacitor in the VTM Hybrid readily provides 400 – 600 amps during launch and regen cycles.
The ultracapacitors also have an expected life of 2 million charge / discharge cycles. They are guaranteed for one million charge-discharge cycles. Given a typical duty cycle of seven stops per mile, this equates to over 140,000 miles.
Ultracapacitors are an extremely good fit for high duty cycle hybrid applications and they exceed the 1,000 cycle rating of high energy battery technology by a wide margin.
Total hybrid system weight, with ultracapacitors, is only 630 pounds. This is 1,000 pounds lighter than competitive systems using batteries.
Also, the lower voltage of the ultracapacitors, 60-94 volts, is a safety advantage over battery-powered hybrid systems using 300-500 volts.
