Electric cars are a trending topic we hear often and it is noticeable how people get interested in them day by day. This article hence provides the technology behind the electric cars to enhance your knowledge on all whatnot.
The term electric vehicle is referred to a wide range of vehicles which includes,
Hybrid-electric vehicles
A type of electric vehicle where the combustion engine is combined with an electric motor, and battery.
Plug-in hybrids
A type of electric vehicle that has a battery that can be charged by plugged-in and is enough for short-range travel on battery power alone. In longer-travels, the combustion engine kicks in when the battery runs out.
Battery electric cars
These type of electric vehicles runs entirely on battery power and they can be recharged.
Fuel cell vehicles
This uses hydrogen gas to power the electric motor.
Of the Electric cars, it is noticeable that In battery electric cars mainly contains a motor and a battery pack to power the motor. There are two types of motors used in electric battery cars now.
In these Induction motors and Permanent Magnet, motors are used especially for new designs. Induction motors and Permanent motors consume AC power and in those cars, there are inverts to convert DC power to Ac power before reaching the motor. For example, Nissan Leaf has a Permanent Magnet motor and Tesla Model S uses an Induction motor.
Even though The Permanent Magnet motor provides high power density and high efficiency, these motors are very expensive. As for the Induction motor, they are cheaper to manufacture and maintain compared to Permanent Magnet motors but the efficiency and power density are lower.
The speed of the motor depends on the frequency of the power supply, so we can easily control the speed of the motor by varying the frequency of the power supply. Varying the frequency of the power supply is done by the inverter, so through the inverter, the speed of the car can be easily and effectively managed.
The battery pack is one of the most important parts in the battery electric car. Battery packs provide DC power so as mentioned before the inverter converts the DC power to AC power. If the battery pack has more power capacity then we have more travel time. So the electric car companies pay great attention to this and they constantly try to increase the capacity of the battery pack.
Tesla Model S has one of the most effective and efficient battery packs in the industry. Here Tesla uses small lithium-ion cells rather than larger batteries and these are similar to the batteries we use daily. The reason behind using smaller cells is it enables the efficient temperature control which increases the lifespan of the battery pack. As you can see in the picture the coolant goes through the gap between the ion cells.
In most of the battery electric cars, the battery pack is situated close to the ground, so the center of gravity of the car pulls towards the ground which improves the stability of the car and also provides structural support.
In some battery electric cars, they include systems to regenerate electric power. For example in Tesla Model S, it has a technology called regenerating braking system. Here when the driver tries to slow down the car he takes his foot off the acceleration paddle and at that time the regenerating braking system activated and the Induction motor inside the car acts as a generator and that generated power can be stored in the battery pack for future use.
The Advantages of Using a battery electric cars
- Cheaper to run (There is no need to buy gasoline)
- Cheaper to maintain (There is no need for services required in petrol/diesel vehicles but we need to replace the battery pack when the time comes.)
- Compared to combustion engine vehicles, safety is improved in battery electric cars.
- Pollution free.
In conclusion, all we could think of is that the advancement of these electric cars will have a larger impact on the world with the above-listed advantages.
On behalf of team LiveRoom, written by Ruchira Ruwantha
