When charging with a DC charging unit, the primary factors determining the charging speed are as follows:
- Charging Unit Power
- Your Vehicle's DC Charging Speed
- Maximum Current Passing Through the Charging Unit's Cable
- Your Vehicle's Voltage Architecture
Charging Unit Power:
The power of the charging unit is a fundamental factor that determines how quickly it can charge an electric vehicle. A 120 kW charging unit can theoretically charge your vehicle at a rate of 120 kilowatts. However, this is under ideal conditions, and in reality, it may not be possible to receive the full power.
Your Vehicle's DC Charging Speed:
Every electric vehicle accepts DC charging at different speeds. This depends on the vehicle's battery management system and charging algorithm. For instance, some vehicles may accept high-power charging more quickly, while others charge at a slower rate.
Maximum Current Passing Through the Charging Unit's Cable:
The maximum current passing through the charging unit's cable determines the power delivered to the charging vehicle. For example, a charging unit with a 200 Ampere cable can provide a maximum of 200 Amperes of current. However, the vehicle's battery may not fully accept or manage this current.
Your Vehicle's Voltage Architecture:
The battery architecture of electric vehicles typically operates within a certain voltage range. The voltage of the charging unit must be compatible with the vehicle's battery voltage. For example, if your vehicle has a 400V architecture and the charging unit cannot provide the appropriate voltage, this can affect the charging speed.
Let's now see how these factors can interact with examples:
For instance, you have a vehicle with a 400V architecture and are using a 120 kW charging unit. However, if the maximum current passing through the charging unit's cable is only 200 Amperes, your vehicle can receive a maximum of 80 kW. This is because the power (P) formula is calculated as P = V x I (power = voltage x current). Therefore, if your vehicle can receive a maximum of 200 Amperes at 400V, you can receive 400V x 200A = 80 kW. Thus, the maximum current passing through the charging unit's cable determines the maximum power your vehicle can receive.
