Extended-range electric vehicle with supercapacitor range extender

Abstract

A vehicle includes an engine, fraction motor, final drive assembly, battery pack, and a supercapacitor module electrically connected to the battery pack. The vehicle also has first and second clutches and a controller. The clutches have opposite apply states. The first clutch connects an engine driveshaft to the motor to establish a neutral-charging mode. The second clutch connects an output shaft of the motor to the final drive assembly to establish a drive mode. The controller selects between the drive and neutral-charging modes in response to input signals. The drive mode uses energy from the supercapacitor module and battery pack to power the traction motor. The neutral-charging mode uses output torque from the engine to charge the supercapacitor module and battery pack. The clutches may be pnemauically-actuated, and the vehicle may be characterized by an absence of planetary gear sets.

Description

TECHNICAL FIELD[0001]The present disclosure relates to an extended range electric vehicle having a supercapacitor range extender.BACKGROUND[0002]An extended-range electric vehicle powertrain provides one or more electric-vehicle (EV) modes. In an EV mode, a high-voltage electric traction motor is powered via a rechargeable battery pack. Output torque from the electric traction motor is typically delivered to a transmission having one or more planetary gear sets. Braking energy may be recovered during a regenerative braking event to recharge the battery pack. When a state of charge of the battery pack is depleted, the EV range of the vehicle may be extended by selective operation of a small internal combustion engine, with engine torque used to generate additional electricity as needed.SUMMARY[0003]An extended-range electric vehicle is disclosed herein. The vehicle includes a powertrain having reduced cost relative to conventional designs. The powertrain makes selective use of a stor...

AI Technical Summary

Benefits of technology

The patent is about a new powertrain design for electric vehicles that includes a battery pack and a supercapacitor module. The supercapacitor module helps preserve the battery pack's charge by using its stored energy to prevent the battery from getting fully discharged. This helps extend the battery's useful lifespan. The design also allows the engine to operate at its best efficiency point and provides power to various electrical loads such as air conditioning. The controller selects between a drive mode and a neutral-charging mode, depending on the vehicle's needs. Overall, the invention improves the powertrain's energy efficiency and performance.

Problems solved by technology

Lead acid batteries are typically less efficient at recovering regenerative braking energy relative to lithium ion and nickel metal hydride batteries.

Similarly, lead acid batteries may not provide the required power as effectively or efficiently as these other common battery types, particularly during periods of peak vehicle acceleration.

As with most battery types, frequent charging and discharging may serve to reduce the useful operating life of the battery pack.

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