What’s in a Hybrid Car?

Hybrid cars are designed with one task in mind – getting the best possible fuel efficiency. They use low friction tires, less air-con usage and a power train that is precisely tuned to achieve the best mpg.


They are most efficient in stop-and-go city traffic where the electric motor does much of the work. The petrol engine only kicks in when the battery is running low.

Regenerative braking

When you step on the brake pedal in a hybrid car, the vehicle’s electric motors run backwards, using the friction of their wheels against the road to slow and stop the car. But instead of wasting that energy by simply converting it into heat, the system captures this kinetic energy and feeds it back into the battery pack to help replenish its energy.

It’s estimated that regenerative braking can add hundreds of miles to your EV or hybrid driving range throughout the course of a year. However, the amount of kinetic energy that is captured and fed back into the battery depends on a variety of factors, including driver style. Drivers who slam on the brakes can lose as much as 70 percent of the system’s potential efficiency.

Hybrid cars use regenerative braking most often when driving at lower speeds, in stop-and-go traffic, and while climbing hills. For higher speed highway travel or extended periods of uninterrupted idling, most hybrids rely on conventional hydraulic brakes to stop the vehicle. This means that hybrid drivers tend to replace their brakes far less frequently than regular car owners do. The system can also change the way your brake pedal feels, which might take some getting used to for new EV or hybrid drivers. The pedal may feel less firm or might depress farther down toward the floor than you’re used to when the regenerative system activates.


The battery in a hybrid car is central to its fuel efficiency. It stores energy that’s captured during braking and drives the electric motor, reducing the load on the gas engine and cutting down on emissions. The battery in a hybrid vehicle can be made from lead-acid, nickel-metal hydride, or lithium-ion. Lead-acid is the most common, but it’s highly toxic and heavy, reducing some of the fuel economy gains. Nickel-metal hydride is less toxic, but it still contains carcinogenic materials and the mining process is considered hazardous. Lithium-ion is the most advanced battery type, with superior durability and cooling performance, resulting in better fuel efficiency and lower costs than nickel-metal hydride and lead-acid batteries.

The battery pack in a hybrid vehicle can be repaired by replacing damaged cells and modules. However, it’s a specialized job and should be performed by a qualified technician with access to the necessary OEM-approved testing, diagnostic, and charging equipment.

Fully electric vehicles (EVs) use a rechargeable battery instead of a gasoline engine and can travel long distances on pure electric power alone. However, they require a long charging time at home or public chargers and can be inconvenient for drivers who don’t live near an EV charging station or take many long road trips. Hybrid cars, on the other hand, are ideal for commuters who want cheap, convenient urban transportation without any tailpipe pollution.

Electric motor

The electric motor in a hybrid car converts electrical energy into physical motion that moves the vehicle. When used in reverse as a generator, it can recapture energy that would otherwise be lost to friction when the brakes are applied (regenerative braking). It also helps recharge the battery.

Depending on how the vehicle is driven and where you live, an electric motor can sometimes do all the work and eliminate fuel consumption. However, recharging an all-electric vehicle can take much longer than filling up with gas. And you’ll have to find public charging stations to use on long road trips.

Most hybrid cars rely on their gasoline engine to supplement the electric motor’s power. This combination is most effective for city driving, where both the IC and electric motors can operate together to reduce emissions and noise. It’s less efficient on highway stretches and climbing hills, where the gasoline engine must do most of the work.

In the most common hybrid design, a parallel hybrid has an electric motor and gasoline engine connected with a single transmission that blends both drives. The transmission type and size influence how the car accelerates, sounds, and feels. Some parallel hybrids, such as the Toyota Prius and Chevrolet Volt, have a continuously variable transmission, while others use an electronic CVT called a power split-CVT.

Gas engine

Hybrid cars use two power sources: a gasoline engine and an electric motor. This allows them to operate more efficiently and reduce emissions. Hybrid vehicles are often more expensive to purchase than traditional gas-powered vehicles, but many save you money on fuel costs over time.

Most hybrid cars have a small electric motor that can help the car accelerate and generate power on deceleration (regenerative braking). This helps to reduce the demands on the gasoline engine, which in turn lowers fuel consumption. Some models also have a feature called “idle-off” that shuts off the engine when you stop at red lights or in traffic, saving even more fuel.

Unlike conventional brakes, which waste kinetic energy as friction heat, hybrid vehicles’ regenerative braking systems capture some of that kinetic energy and transform it into electricity to charge the battery. This not only improves the vehicle’s range and efficiency, but it also reduces noise emissions.

There are many different types of hybrids, and the most popular model is the Toyota Prius. These hybrids run primarily on the electric motor up to 15 mph, which makes them most efficient in city driving. They use the gasoline engine to drive the wheels during high speeds and when more power is needed, such as accelerating and climbing hills. Full hybrids use both the gas and electric engines to drive the wheels, and can be recharged using regenerative braking or by plugging into an outlet at home.