Here's why:
* Energy flow: Electric cars use the same battery to power both the motor and the charging system. When the car is running, all the energy from the battery is directed towards the motor to keep it moving.
* Safety: Charging an electric car while it's running would create a dangerous electrical overload. The high voltage and current involved could damage the car's electrical system, the charging station, or even cause a fire.
* Charging system design: Electric cars are designed to charge only when they are stationary and the engine is off. This allows the battery to receive maximum charging power without any interference from the car's other electrical systems.
In short, you need to stop your electric car and turn off the engine before you can plug it in for charging.