AC vs DC EV Charging: What Actually Changes
The difference is where the current is converted. Batteries only store direct current (DC), but the grid supplies alternating current (AC). In AC charging, the conversion happens inside your car using its onboard charger — which is small, so the speed is capped at roughly 3.7–22 kW. In DC fast charging, a much larger converter inside the station does the work and feeds the battery directly at 50–350 kW.
Side by side
| AC charging | DC fast charging | |
|---|---|---|
| Converter location | In the car (onboard charger) | In the charging station |
| Power range | 3.7 – 22 kW | 50 – 350 kW |
| Limited by | Your car's onboard charger | The station and the battery's accepted rate |
| Connector (Europe) | Type 2 | CCS Combo 2 |
| Cable | Usually yours, carried in the car | Always tethered to the station |
| Cost per kWh | Lower | Typically 1.5 – 3× higher |
| Battery impact | Gentlest | Slightly more thermal stress |
| Typical use | Overnight, workplace, long stays | Motorway stops, quick top-ups |
Why your car, not the charger, usually sets AC speed
Every EV has an onboard charger with a fixed maximum: commonly 7.4 kW (single-phase) or 11 kW (three-phase), sometimes 22 kW. Plug that car into a 22 kW post and it will still draw only its own maximum. This is normal and is not a fault.
It also means that paying for a faster AC installation at home is pointless if your car cannot use it. Check your car's onboard charger rating before specifying a home unit.
Why DC charging slows down as you fill up
A DC charger does not deliver its headline power for the whole session. The battery management system requests a rate that falls as the state of charge rises — the charging curve. A car that peaks at 150 kW at 20% might be down to 70 kW at 60% and under 40 kW at 85%.
The practical consequence: charging from 10% to 80% is usually much faster than 80% to 100%. On a long journey, two stops to 80% almost always beat one stop to 100%.
Which to use, and when
- Use AC whenever the car is going to be parked for hours anyway — overnight at home, all day at work, during a hotel stay. It is cheaper and easier on the battery.
- Use DC when the charge itself is the reason you have stopped — motorway journeys, or when you need range quickly.
Most EV drivers end up doing roughly 80–90% of their charging on AC and only a handful of DC sessions a month.
What about "Level 1, 2 and 3"?
That is the North American naming for the same idea: Level 1 is a domestic 120 V socket (about 1.4–1.9 kW), Level 2 is 240 V AC (3.7–19.2 kW), and "Level 3" is an informal name for DC fast charging. European documentation generally uses AC/DC and the kW figure instead, which is less ambiguous.
Finding the right one
Because the two modes serve completely different purposes, filtering matters. In Voltika you can set a minimum power — for example only show chargers of 50 kW or more when you are on a journey, or only AC posts when you are looking for somewhere to leave the car overnight. Browse by city in the station directory.