For most home charging setups, a Level 2 charger fully recharges an electric vehicle in roughly 4 to 10 hours, which is why so many EV owners simply plug in overnight and wake up to a full battery. The exact time depends on a few things: how powerful the charger is, how big the battery is, how empty it is, and how fast your car can accept a charge.
Here is how to estimate charging time and what affects it.
The simple math
You can estimate charging time with one basic formula:
Charging time (hours) = battery size (kWh) divided by charging power (kW)
Level 2 charging runs on 240 volts, and the power depends on the amperage:
- 32 amps is about 7.7 kW
- 40 amps is about 9.6 kW
- 48 amps is about 11.5 kW
So a 60 kWh battery charged from empty on a 9.6 kW charger takes roughly 6 to 7 hours in theory. Real-world charging runs a bit longer because of charging losses and the way charging slows as the battery nears full.
How much range you gain per hour
Another helpful way to think about it is miles of range added per hour of charging:
| Charger output | Approx. power | Range added per hour |
|---|---|---|
| 32 amps | 7.7 kW | About 25 to 30 miles |
| 40 amps | 9.6 kW | About 30 to 37 miles |
| 48 amps | 11.5 kW | About 37 to 44 miles |
These figures assume a typical efficiency of roughly 3 to 4 miles per kWh. A more efficient car gains more range per hour, and a larger or less efficient vehicle gains less.
Your car’s onboard charger sets a ceiling
Here is a detail that surprises many new EV owners. Your vehicle has an onboard charger that limits how fast it can accept AC power. If your car tops out at 7.7 kW, then installing an 11.5 kW charger will not charge it any faster, because the car, not the charger, is the bottleneck.
Common onboard charger limits fall around 7.2, 7.7, 9.6, and 11.5 kW. Before paying for a higher-amperage charger, it is worth checking what your vehicle can actually accept, since a faster charger only helps if the car can use the extra power.
What else affects charging time
A few other factors influence how long charging takes:
- Starting charge level. Charging from 20 percent to 80 percent is faster than a full 0 to 100 percent, and most daily charging is just a top-up.
- Charging taper. Charging slows as the battery approaches full to protect the cells.
- Temperature. Cold weather can slow charging until the battery warms.
- Battery size. A larger battery simply holds more energy and takes longer to fill.
Do most people really charge overnight?
For the majority of drivers, yes, and they rarely start from empty. If you drive an average amount each day, a Level 2 charger replaces that energy in a couple of hours, and a full overnight window is more than enough. Level 1 charging, which uses a standard 120-volt outlet, is far slower at roughly 3 to 5 miles of range per hour, which is why most owners upgrade to Level 2 for daily charging.
A Level 2 charger typically charges an EV in about 4 to 10 hours for a full charge, adding roughly 25 to 44 miles of range per hour depending on the charger’s amperage and your car’s onboard charger. To estimate your own time, divide your battery size in kWh by your charging power in kW, and remember the car’s onboard limit sets the maximum speed. For most drivers, an overnight charge is plenty.
Stella Electric installs Level 2 EV chargers sized to your vehicle and your home’s electrical capacity, serving homeowners across the Baltimore area and throughout Maryland with flat-rate pricing and no overtime charges. We will help you match the charger to your car so you are not paying for speed you cannot use. Financing is available on qualifying projects.
