Charging an electric car is a fundamental part of ownership. With ‘full’ batteries, you won’t be hit by range anxiety so severely, and you’ll have more confidence in your car. However, the amount of time it takes to charge an EV depends highly on various factors.
Generally, a Level 2 charger will take about six or seven hours to charge from 20% to 80%. A DC Fast Charger might take half an hour to do the same thing.
What factors can affect charging time? How do you speed up charging or keep the batteries at a relatively high level most of the time?
Read this guide at Electrly to learn more!
There are three charging levels you could use to charge your EV. The higher the ‘level’, the faster your car will charge.
- Level 1 (household AC)
- Level 2 (AC)
- DC Fast Charger (DCFC, colloquially ‘Level 3’)
Level 1 AC EV chargers run off the 120 volts coursing through your home. By simply plugging into an outlet and running the cord out to the connector and car, you’ll use your household’s electrical setup to charge the batteries.
Although this is the most convenient option (it doesn’t usually require additional setup or costs), it’s by far the slowest. Charging a standard EV to 100% will often take up to three days.
Level 2 chargers are the most common and probably what you picture when you think of charging EV. Wall chargers fitted to homes are examples of Level 2 units.
Level 2 EV chargers use 240 volts. They can be used in residential settings, provided they’re installed by a qualified electrician. These chargers are much faster than Level 1 models and typically take five to ten hours to charge an EV from empty to full.
The last option is DC Fast Chargers (DCFCs). Often referred to as Level 3 chargers, these units are incredibly powerful. They have their own built-in AC/DC converter and use a separate circuit to bypass the one in your car.
The result can be a charging power of up to 350 kW. In a new EV with a high acceptance rate (‘charging capacity’, below), you could be fully charged in half an hour.
The third-generation Tesla Supercharger is an example of a Level 3 charger. It is a DC fast charger with a charging power of 250 kW. This allows for faster charging times compared to Level 2 chargers. For instance, it can add 75 miles of range to a Tesla Model 3 in just 5 minutes.
Charging Capacity of the Car
No matter how powerful the charging station is, your car has its own charging capacity and acceptance rate. This will have a significant impact on the charging speed.
The charging capacity refers to the power of the car’s onboard AC/DC converter (which is technically the battery charger, powered by the grid after you plug it in).
For example, new Teslas (apart from the Model 3 RWD) have an 11.5 kW converter. In other words, they’ll always top up at a maximum of 11.5 kWh per hour when plugged into an AC source.
The acceptance rate refers to using DC fast chargers. It’s the maximum amount of power your car can convert into chemical energy in the battery, no matter how powerful the charging station itself is.
For example, a car with a 50 kW acceptance rate will top up its batteries at a maximum rate of 50 kWh per hour, even if you’re plugged into a 250 kW Tesla Supercharger.
The newer your EV, the more likely you’ll have a more significant acceptance rate. Most new electric cars come with 200 to 250 kW acceptance rates. However, older models might have a 50 kW DC limit, and the oldest probably aren’t compatible with DC fast chargers at all.
Size of the Battery
The battery size also makes a difference. The greater the capacity, the more charge needs to be added.
Battery capacities are measured in kWh. The Tesla Model 3, for instance, has a 57.5 kWh capacity. The largest we’re currently seeing are around 120 kWh, although that’s likely to increase in the near future.
Of course, you don’t need to constantly top an EV battery up to 100%. In fact, many studies suggest 80% is the optimal point. But, if you charge it to the maximum at every opportunity, note that it’ll take longer (and cost more).
Top-up charging is an effective way to ensure you always have enough in your batteries.
Most EVs spend almost all their time parked. This presents an opportunity to keep the batteries topped up.
Instead of waiting for the charge level to get low, consider plugging your car in whenever you have the opportunity. When you get home at night, overnight charging will ensure your car’s always at optimal capacity.
Consider combining top-up charging with a charge limit of 80% to maximize your battery’s longevity.
All these other factors will also make a difference concerning how long an electric car takes to charge:
- Weather - batteries and charge points are happiest in a particular temperature range. They really start to struggle in sub-zero weather patterns. Charging will therefore take longer and, in extreme cases, actually won’t work at all.
- Battery condition - over time, the sad end of all lithium-ion batteries is that they deteriorate. Modern advances mean they last much longer than they used to, though. However, it might be time for a new set if your car’s batteries are 10 years old or older. Poor-condition batteries won’t hold charge as long and will impact the charging time.
- Other electrical loads - when charging, you might be drawing current to power other loads in the car. Some minor circuits, such as the alarm and the central locking, are always active. You may also use cabin pre-conditioning or the radio while waiting. All these increase how long it’ll take to charge your EV.
- Time of day - the more EVs we have on the roads, the greater the demand from the electrical grid. Thus, it might take longer when the load is stretched at specific points of the day.
In summary, a Level 2 charger is plenty to top your battery up over a few hours. ‘Level 3’ DCFCs can charge to 80% in a matter of 30 minutes but should only be used for a quick top-up in emergencies. There’s no need to spend extra to use them regularly.
Setting an 80% charge limit is an effective way to protect the long-term health of your batteries. Combine this with the top-up charging method, and you’ll rarely have to worry about range.
As you get used to your EV and its charging requirements, you’ll learn how to allocate time effectively.