Your complete guide to EV charging speeds: slow, fast, and rapid charging explained

19 January 2021 | Matt Mostyn

One of the most common questions for EV drivers is how long it takes to charge an electric car. After all, nobody wants to be waiting around for their battery to power up before they can hop in and dash to the shops.

In this article, we’ll look at the 3 main options for EV drivers – including slow, fast and rapid charging. We’ll tell you the pros and cons of each method, as well as the amount of power used, and how long it usually takes to charge up.

EV charging speeds

There’s one easy way to get a rough idea of how long it takes to charge up your EV. Just check the power rating of the charger you’re using. A charger that’s around 3kW will give a slow charge, averaging around 10-14 hours. Meanwhile, a charger with 7kW – 22kW will give your EV a “fast” charge – usually in around 4 to 6 hours. And finally, a 50kW – 120kW charger is classed as a “rapid charger”, and will give you a full charge in about an hour.

Here’s some further detail on each:

Slow charging an electric car

They might take a little longer – but slow chargers are arguably the simplest, most convenient method for charging your EV.

Slow charging is ideal for using at home – and slow charging points are also the type usually found at workplaces.

Slow charging units are what’s called “untethered”. That means you’ll need a cable to connect your car to the charge point. Most EVs come with a cable, which you just plug into your normal socket, and these have a charging rate of 3kW.

Slow charging rates range between 2.3 kW and 3 kW, depending on the location. If you’re charging at home,  via a 3-pin plug, your car will usually draw 2.3 kW (10A). But if you’re using a lamp-post charger, they’re often rated at 5.5 kW – though you’ll likely also find some 3 kW lamp-post chargers.

Charging times on a slow charge

For slow charging, the time it takes to reach 100% can vary, depending on the charging unit, and EV being charged – but a full charge on a 3 kW unit will typically take around 10-14 hours. And for cars with a larger battery, it could take even longer, especially if you’re charging it from empty.

Why choose slow charging for your EV?

Because it takes a bit longer, slow charging is the ideal option for charging an EV at home overnight. And while it’s possible to slow charge your vehicle using a standard 3-pin socket, it’s a better idea to get yourself a dedicated EV charging unit installed by an accredited installer. That’s because EVs need to be plugged in for quite a while, and they also need a higher current – so a proper charging unit can handle the heavy use more efficiently.

Read our guide to find out more about the different EV connectors and plugs, and how to choose the best for you.

Fast charging an electric car

Fast charging an EV

One step up from slow charging is the appropriately-named fast charging option. You’ll find these types of chargers at numerous urban locations, from supermarket car parks to shopping centres, cinemas and retail parks – in fact, anywhere you might want to park your vehicle and leave it for a while.

You can also get a fast charger installed at home – and you can also take advantage of a Government grant to help fund the installation.

Charging times on a fast charge

A 7kW fast charger will power up your EV battery in around 4-6 hours, while a 22kW unit could do the job in a couple of hours. 

Most fast chargers are untethered – though some home and workplace units come with cables attached.

If your charger is tethered (ie with a cable attached), you can only charge a car model that’s compatible with that connector type. This is down to the plug type at the end of the cable being used. For instance, a Type 1 tethered cable could be used by a first-generation Nissan Leaf, but not a second-generation Leaf, which uses a Type 2 inlet. 

Find out more about the various types of cables and plugs you can use to change your EV by checking out our blog on the subject.

Why choose fast charging for your EV?

Fast charging is, of course, a lot quicker than slow charging. And if you’re out somewhere anyway, and intending to leave your car parked for a while, it really is the ideal solution for charging up while your EV is idle.

Having said that, there is some research to suggest that regular fast DC charging can reduce the lifespan of lithium-ion batteries. But the good news is that EVs automatically limit the power to its maximum capacity, to minimise wear on the battery. And the rate of charge is also automatically lowered if the car thinks too much power is being supplied to the battery too often.

Read our guide to find out more about EV batteries, and how long they can last.

Rapid charging an electric car 

Rapid chargers use a high-power direct or alternating current to recharge a car in the quickest possible time. They can charge an electric car to 80% full in as little as 20 to 30 minutes (with the final 20% usually taking another 20 minutes). Pretty speedy!

It’s worth pointing out that they use a huge amount of power – so you won’t be able to get one installed at home. Instead, you’ll find them at motorway service stations and other public charging hotspots. 

Rapid AC chargers give 43 kW of power (three-phase, 63A) and use the Type 2 charging standard. Find out more about Type 1 and Type 2 cables in our guide to charger cables and plugs.

Charging times on a rapid charge

While rapid chargers can take an EV battery to as much as 80% in as little as 20 minutes, an average new EV would take around an hour on a standard 50 kW rapid charge point. 

Ultra-Rapid DC chargers use as much as 100 kW of power (or sometimes even more). These are the next-generation of rapid charge points, and they help to minimise recharging times, in spite of the increasing battery capacity of newer EVs. 

For EVs capable of accepting 100 kW or more, charging time can still be as short as 20-40 minutes for a typical charge – even for those with a large battery capacity. And if your EV can only accept a maximum of 50 kW DC, you’ll still be able to use ultra-rapid charge points, because the power is restricted to whatever your car can handle. 

Why choose rapid charging for your EV?

When you use a rapid charger, even just 15 minutes of charging would usually give you a 30-40 mile range – often more than enough to get you home. That makes them super-convenient, reducing “range anxiety” and making the idea of having an EV much more appealing for many of us.

You’re also much more likely to use a rapid charger on a long journey than a shorter one… so it’s a great opportunity to stretch your legs, grab a hot drink, and nip to the loo while you wait.

All rapid charge devices are tethered to the unit, so you’ll need to make sure your EV is compatible with the charger you want to use. Plus, rapid charging can only be used on vehicles with rapid-charging capability. Most rapid chargers use either the CHAdeMO or CCS charging standards. But luckily, these are the most common types, so it’s likely that your EV can use them.

To help protect the battery, the charging speed is reduced as the battery gets closer to full charge. This means that (as with fast charging), the battery’s lifespan is protected as much as possible, even with regular use.