How Long Does It Take To Charge An Electric Car?

Charging time is a hot topic when it comes to electric cars. 

Here we look at all the methods and what are the best approaches to keep you going.

Slow Charging 

As the name suggests, this method results in the longest charging times. With some larger EVs needing up to 24 hours to replenish their batteries when charged this way. Normally running at about 3kW, these chargers are occasionally still found at public charging points. But are more often than not the portable type that feature a three-pin plug for use with a domestic electricity supply. 

Most electric cars get one of these units as standard. But the ever increasing size of battery packs mean that most manufacturers recommend using them only when no other charging method is available. Of course, if you don't cover many miles a day, then slow charging allows you an easy way to top-up the car's cells overnight. While the slow rate of charge means less heat is generated in the battery, which can help prolong its useful life.

Fast charging 

This is quickly becoming the most popular method of charging, particularly for domestic use. Fast charging runs at either 7kW or 22kW, with the latter usually being reserved for public charging points. 

Most dedicated domestic wallboxes run at the lower 7kW rate, which roughly halves the time it takes for a full charge compared to a slow charger. So for example, you can expect a car with a 40kW battery to be fully recharged in about six hours. While a car with a 75kW battery will require about 12 hours. 

22kW requires a three-phase electricity supply, meaning they are a rare and expensive solution at home. They also require a car that can accept Direct Current (DC) charging as well as the more prevalent Alternating Current (AC) method. If your car can accept this rate of charge, then expect charging times to be slashed by around half compared to the 7kW unit. Therefore a 75kW car with DC electric charging will be charged in under six hours.

Rapid charging

On paper, this is by far the fastest way of topping up the batteries in your EV. With some chargers able to deliver a significant amount of power within just 20 minutes. Charging at anything from 50kW to up to 350kW, these units are usually found at motorway service stations and dedicated charging hubs. For the best results, you'll only charge up to 80 percent of the battery's capacity. This is because beyond this point the rate of charge slows significantly to protect the cells from the high temperatures involved in such high electrical currents. 

Of course, to make use of this capability you'll need a car with a charging system that can accept rapid charging. Most entry-level models are available with an optional upgrade that allows DC charging of up to 100kW, while more expensive models can charge at a rate of 250kW. Some newer variants now use an 800-volt electrical system that can handle up to 270kW.

To give an idea of speed, a 40kW vehicle using a 50kW charger (currently the most popular in the UK).  Can be charged to 80 percent of its capacity in as little as an hour. However, regardless of the power of the charger itself, your car will only be able to charge at the maximum rate of its onboard system. So for example, a vehicle with a 50kW charging capability will receive current at this rate even when plugged into a 350kW charger 

Top up charging 

 This is the method that most EV drivers take advantage of, which is to plug in and charge whenever you get an opportunity. Usually at a public charger on the street or in the supermarket car park. So rather than waiting for the battery to run flat completely, it's actually easier and quicker to simply keep the cells topped up. This means you'll usually have plenty of charge and so rarely suffer from range anxiety. Owners usually combine this technique with a full charge overnight using a domestic slow or rapid charger. 

How much range do you get per hour of charging? 

As you'd expect, the answer to this depends on the charger you're using, and to a lesser extent your car (not all are capable of rapid charging). However, as a guide, you can expect a standard 3kW slow charger to add 10 miles of range after an hour. 

Step up to a fast charger with a delivery of 7kW, which is the rate most domestic wall boxes charge at. Then after 60 minutes, you'll have added up to 30 miles. 

By contrast, a 50kW rapid charger can theoretically add 175 miles of range in this time. Although you'll need a large battery to achieve this. As with smaller units, you'll be getting into the last 20 percent of capacity when charging slows. It's a similar case with 150kW chargers, but as an indication of how effective they are, you can add 100 miles of range in as little as 10 minutes.