High fuel efficiency.

Decreased emissions.

No need of fossil fuels.

Less overall vehicle weight.

Regenerative braking can be used.

Toyota Prius Honda Insight Honda Civic(hybrid

ThermalManagementsystemHybridPower unitTractionmotorEnergyStorageunitAccessoriesFuel tankBody chassisEnergy management& system control

HEVs will contain a mix of aluminum, steel, plastic, magnesium, and composites (typically a strong, lightweight material composed of fibers in a binding matrix, such as fiberglass).

Ultra capacitors are higher specific energy and power versions of electrolytic capacitors devices that store energy as an electrostatic charge.

Lead acid batteries, used currently in many electric vehicles, are potentially usable in hybrid applications. Lead acid batteries can be designed to be high power and are inexpensive, safe, and reliable.

Flywheels store kinetic energy within a rapidly spinning wheel-like rotor or disk. Ultimately, flywheels could store amounts of energy comparable to batteries. They contain no acids or other potentially hazardous materials. Flywheels are not affected by temperature extremes, as most batteries are.

Fuel cells offer highly efficient and fuel-flexible power systems with low to zero emissions for future HEV designs. There are a variety of thermal issues to be addressed in the development and application of fuel cells for hybrid vehicles.

Spark ignition engine mixes fuel and air in a pre-chamber. Throttle and heat losses, which occur as the fuel mixture travels from pre-chamber into the combustion chamber.

A Compression Ignition engine achieves combustion through compression without use of sparkplug. It becomes CIDI engine when it is enhanced with direct injection.

Motors are the "work horses" of HEV drive systems. In an HEV, an electric traction motor converts electrical energy from the energy storage unit to mechanical energy that drives the wheels of the vehicle. Unlike a traditional vehicle, where the engine must "ramp up" before full torque can be provided, an electric motor provides full torque at low speeds. This characteristic gives the vehicle excellent "off the line" acceleration.

As emissions standards tighten and exhaust control technologies improve, the issue of evaporative emissions becomes increasingly important. Thermal management of fuel tanks is one approach to reducing these emissions.

60% to 80% of amiss ions in an autos typical driving cycle comes from cold start emissions, that is, pollutants that are emitted before the catalytic converter is hot enough to begin catalyzing combustion products.

Heat recovered from any of the above sources can be used in a variety of ways. For winter driving, heat recovery from HEV sources such as the power unit exhaust, propulsion motors, batteries, and power inverter can significantly improve cabin warm-up.

HEVs are now at the forefront of transportation technology development. Hybrids have the potential to allow continued growth in the automotive sector, while also reducing critical resource consumption, dependence on foreign oil, air pollution, and traffic congestion.