Gasoline-powered vehicles utilize an internal combustion engine.  Electric vehicles are powered using a battery that is charged by plugging it in.  Hybrid electric vehicles are a combination of both of these.  Hybrid electric vehicles have not only an internal combustion engine, as well as a battery-powered electric motor.  Unlike the fully electric vehicles, these batteries are not charged by plugging in, but by capturing excess energy with regenerative braking and from the internal combustion process.  The electric battery takes over powering the auxiliary load as well as reducing idling while braking.  The internal combustion engine in a hybrid electric car can be smaller than traditional gasoline powered vehicles because the electric motor takes on some of the load.

Let’s discuss some of the important parts in a hybrid electric car. 

Auxiliary Battery – The auxiliary battery in a hybrid electric vehicle provides energy to the vehicle accessories as well as the energy to start the vehicle initially before the traction battery is started.

DC/DC Converter – The traction battery uses higher-voltage electricity than the auxiliary battery.  The DC/DC converter converts the higher-voltage DC of the traction battery to the lower-voltage needed to recharge the auxiliary battery.

Electric Generator – When the wheels of an electric hybrid vehicle go from rotating to braked, the energy is captured and converted into electricity by the electric generator.  

Electric Traction Motor – The electric traction motor powers the wheels of the vehicle.  Sometimes this is combined with the electric generator for a single motor generator that both drives the wheels and captures the energy from braking.

Exhaust System – Exhaust systems focus the vehicle’s exhaust and funnel it out by the tailpipe.  Hybrid electric vehicles have a three-way catalyst that reduces the emissions from the exhaust system.

Fuel Filler – The tank is filled with this nozzle from a high-pressure dispenser.

Fuel Tank – The tank where the gasoline is stored inside the vehicle before it is pumped into the engine.

Spark Ignited Internal Combustion Engine – The fuel is fed into the combustion chamber or manifold and mixed with air.  The fuel and air mixture is ignited by a spark (spark plug).

Power Electronics Controller – This system controls the flow of electricity as it heads into the electric traction motor.

Thermal System – The temperature of the engine, motor, and all related systems is controlled and kept at the optimal temperature by this system.

Traction Battery Pack – This battery stores the electrical energy used by the electric traction motor.

Transmission – The mechanical power coming from the engine or electric power from the traction motor is transferred by the transmission to turn the wheels.