Charging Levels & Standards
What are the three main EV charging levels?
Level 1, Level 2 and DC fast charging
Is AC or DC charging normally used for fast charging?
DC
What does EVSE stand for?
Electric Vehicle Supply Equipment
An EV has a 60 kWh battery and charges at 10 kW. Approximately how long does it take to charge?
6 hours
Name one good charging habit that can help protect an EV battery.
Avoid keeping the battery at 100% for long periods.
Which connector is commonly used for AC charging in Europe?
Type 2
What is the main difference between AC and DC charging?
AC charging uses the vehicle's OBC to convert AC to DC; DC charging supplies DC directly to the battery.
What do OBC and kW mean?
On-Board Charger and kilowatt
A 50 kWh battery is charged with a 25 kW charger. Approximately how long will a full charge take?
2 hours
A customer always charges their EV to 100%. What would you recommend?
For daily use, avoid charging to 100% unless necessary; follow the manufacturer's recommended limit.
What is CCS and why is it important for EV charging?
Combined Charging System; it supports AC and DC charging through the same connector system.
Why can a DC charger charge an EV battery faster than a typical AC charger?
DC charging bypasses the vehicle's OBC, allowing high-power DC to reach the battery directly.
What is the difference between kW and kWh?
kW measures power; kWh measures energy/capacity.
An EV has a 75 kWh battery. The charger provides 50 kW. Ignoring losses, how long would a full charge take?
1.5 hours
An EV is connected to a charger but charging does not start. Give two things you would check first.
For example, cable/connector connection, charger status, vehicle charging settings, fault messages or power supply.
A vehicle has a Type 2 socket and a CCS connector. What is the practical difference between the two for charging?
Type 2 is used for AC charging; CCS adds DC fast charging capability.
During AC charging, what component converts AC electricity into DC for the battery?
The OBC
Q: A technician says, “The charger is 150 kW, so the car will always charge at 150 kW.” Is this correct?
No. Actual charging power depends on the vehicle's maximum charging capability, battery state/temperature, charger and other conditions.
A 64 kWh battery is at 25% and needs to reach 85%. A charger supplies 32 kW. Ignoring losses, approximately how long will charging take?
1.2 hours / 72 minutes
A customer reports that DC charging becomes much slower after the battery reaches a high state of charge. Is this necessarily a fault? Explain.
No. Charging power normally decreases at higher states of charge to protect the battery and manage heat.
A technician finds an EV with a CHAdeMO connector and a Type 2 connector. What charging functions would you expect each connector to support?
CHAdeMO for DC fast charging; Type 2 for AC charging.
An EV accepts 11 kW AC but 150 kW DC. Why can the same vehicle have such different charging powers?
AC charging is limited by the OBC, while DC charging can supply much higher power directly to the battery, subject to the vehicle's DC charging limits and conditions
Explain the relationship between EVSE, OBC, CCS, kW and kWh in one technically correct explanation.
EVSE supplies/manages electrical power; the OBC converts AC to DC during AC charging; CCS provides the charging interface for AC/DC; kW measures charging power; kWh measures stored energy.
An 80 kWh battery is at 20%. The charger supplies 100 kW, but the vehicle can only accept 60 kW. Ignoring losses, approximately how long would it take to reach 100%?
64 minutes.
A customer says: “I only use fast DC charging because it's convenient.” Give two pieces of professional advice about charging habits and battery health.
Use DC fast charging when useful, but avoid relying on high-power DC charging unnecessarily; use slower AC charging for routine charging when appropriate, and follow the manufacturer's recommendations for SOC and temperature.