Electric cars have been around for years, in fact that are as old as the car itself. Back in the early days of car design there was a lot of debate over the best way to power a car and many people tried electricity. Eventually the internal combustion engine would win out but the electric car is now making a comeback.
The basic technology behind electric vehicles has been around for well over a hundred years. Electric vehicles run on a fairly simple electric motor. There are a lot of advantages to using an electric motor; the biggest of these is that there are fewer 
moving parts than there are on an internal combustion engine. That means that it is far less likely to break. The other obvious advantage is that by not having to use an internal combustion engine there are no green house gases emitted, at least not by the motor itself. Pollution caused by powering the electric motor is another matter.
Although the idea of an electric motor is fairly simple the challenge is in supplying power to the motor. The earliest attempts at this involved using batteries to hold an electrical charge that could power the motor. This works up to a point but the batteries have a very short lifespan which limits how far you can drive. The batteries that are currently being used can be recharged but this is time consuming. The other problem with batteries is that they are heavy and bulky which makes it necessary to design the car around them. There has been considerable progress at developing batteries that hold a charge that allows for long distance driving and at reducing the size. Nevertheless there is still a fairly long way to go before this becomes a practical option.
Another approach that is being used to build electric cars is the use of a fuel cell. This is a fairly simple technology that combines hydrogen and oxygen to produce water. One of the side effects of this reaction is that it produces electricity which can be used to power a motor. This is one of the more promising approaches to electric cars but there are still some hurdles that have to be overcome. The biggest of these is the difficulty in handling hydrogen which makes it difficult for the average driver to use.
The approach to electric cars that we have had the best success with so far are hybrid vehicles. These work like regular electric cars in that a battery is used to power an electric motor. However there is also an internal combustion engine that is used to charge the battery. This is a long way from the goal of the electric car as originally envisioned but it does allow for vehicles that are more fuel efficient and produce less pollution than regular vehicles.