The battery system in hybrid cars is recharged from the car itself. One way is through the braking system. Electric hybrid motors can take the kinetic energy that comes from applying the brakes and charge the battery. This system is called a regenerative braking system. Working with inertia and torque, magnets on the motor shaft move past the electric coils on the stator eventually producing electricity. This electricity becomes electrical energy that recharges the battery pack.
Another difference about hybrid cars is the tires. The tires are inflated higher to make them stiffer. This reduces drag. After the car stops, the gasoline motor can shut off to save fuel, leaving the electric motor and battery running the car.
Hybrid cars also have two batteries. They have a conventional car battery and a rechargeable battery. Both batteries are rechargeable but they are designed to perform different tasks. A conventional battery is designed to contain enough energy to generate torque to turn over an engine, around 300 RPMs. The colder the temperature is, the more current that is required from the battery to start the engine. There are some minor requirements for the battery when the car is not running like the security system. When the alternator is running, it recharges the conventional battery. If this type of battery is repeatedly drained to empty, its ability to store energy is ruined.
The second battery that a hybrid car has is called a deep cycle battery. It too is rechargeable but is constructed for a very different use. The Nickel-Metal-Hydride (NiMH) batteries are really an array of smaller batteries hooked together. These batteries are designed to be fully drained and recharged repeatedly without damage to the storage capability. Today's NiMH batteries are lighter in weight and deliver more energy than the batteries from previous generations of electric cars. Warranties on these batteries tend to run from eight to ten years or up to 200,000 miles before needing to be replaced.
Currently there are tax breaks for persons purchasing a hybrid vehicle
. There are federal tax breaks but they are being reduced and phased out by 2007. U.S. energy policy can always change though. Several states such as California have deductions and exemptions for hybrid owners. They vary by state so you will have to look them up. In addition, some states, a hybrid car can be driven in High-Occupancy Vehicle (HOV) lanes, even if there is just one person. Hybrid cars are as safe as any other vehicle in their class. They are given the same crash tests and scored the same.
