EVOLUTION ELECTRIC STATION - Solutions for Electric Mobility (Part 4)
The charging time of an electric car depends on the power (kW) at which the charging takes place and on the type of charger used (AC or DC).
Ideally, taking into consideration a car with a 40 kW / h battery pack for a full charge requires these times for an AC charge:
3.7 kW (16A 230V): about 10 hours
7.4 kW (32A 230V): approximately 5 hours and 30 minutes
11 kW (16A 400V): approx. 3 hours and 30 minutes
22 kW (32A 400V): about 1 hour and 40 minutes
While for a 50kW DC recharge: about 50 minutes (increasing the power, the times decrease, for example: 100 kW, 25 minutes)
Be careful though: complete refills are only rarely performed. Those who have an electric car, in fact, are used to making partial recharges ("topping up"), so the real time of occupation of the column is less (this is because whoever arrives at the column does not have the car completely discharged and must not restart fully charged ).
The charging power (kW) is not the only factor that determines the charging times, the other factors are:
• Maximum power accepted (power of the On Board Charger) from the vehicle: some cars accept a maximum of 3.7 kW, others 7.4 kW, others still reach 22 kW (for charging in AC);
• Vehicle battery pack size: electric cars that have a larger capacity battery take longer, those with a smaller battery take less time.
• The cable used for recharging: on the cable socket there is a component that communicates to the column what is the maximum current it can support, the column detects this data and automatically sets itself to deliver the maximum current value.
This means that a 22 kW Mode 3 AC column will not always actually recharge to 22 kW. Two of these three factors are not limits for DC charging because:
• The power is no longer limited by the OBC;
• The cable is integrated in the column, therefore sized for the maximum power supply of the charger itself.