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 injection of energy 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. You’ll need a car that can handle this type of DC charging, and for best results you’ll only charge up to 80 percent of the battery’s capacity, 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 such as the Tesla Model 3 and Model S can charge at a rate of 250kW. Some variants of the Porsche Taycan and closely related Audi e-tron GT use an 800 volt electrical system that can handle up to 270kW, as do the the Hyundai Ioniq 5 and Kia EV6, which can accept charge at up to 200kW. And when Lucid Motors Air goes on sale next year it will be able to charge at up to 300kW.
To give an idea of speed, a 40kW Nissan Leaf using a 50kW charger (currently the most popular in the UK, but more 150 and 350kW units are coming on stream all the time) can be charged to 80 percent of its capacity in as little as an hour, which is around the same time it takes to charge a 75kWh Tesla using a 150kW charger. On a 350kW charger the Taycan takes just over 22 minutes to go from five to 80 percent charge.
However, bear in mind that 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 a Leaf with a 50kW charging capability will receive current at this rate even when plugged into a 350kW charger.
What is 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, which 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.