How long it takes to charge an electric vehicle is an important question when considering which electric car to purchase and your main method of charging.  

The speed at which you can charge an electric car depends on various factors, including the car’s efficiency, the type of EV charger used and – if wondering how long it would take to fully charge – the battery capacity. 

This guide explains everything you need to know about electric vehicle charging, from how long it takes to charge an EV, to different types of chargers and the factors that impact charging speed.

How to work out how long it takes to charge an electric car

To work out the time it will take to fully charge a specific EV, look at its battery size (kWh) and divide this by how powerful the charger is.

Charging Time (in hours) = Battery Size (kWh) ÷ Charging Power (kW)

So the time it would take to fully charge the average 40kwh car using a standard 7kw home charger, would be 5 hours and 42 minutes.  

In practice, it is unlikely that you would be charging a car from 0% – 100%. Manufacturers recommend that you don’t charge your electric car to more than 80% of its full battery capacity, nor let it fall below 20% (and it will not arrive empty). 

To work out how long it would take to recharge your car to a specific percentage, work out how much energy you’re adding by multiplying the percentage by the battery size, and then divide this by the power of the charger. 

Charging Time (in hours) = Energy Added (kWh) ÷ Charging Power (kW)

So to charge the average 40kw electric car from 20% to 80%, would take 3 hours and 26 minutes – if using a 7KW charger.

Different types of chargers and their charging speeds

The actual speed at which you can charge an electric car or van will depend on the method used for charging. The more powerful the charger, the more quickly it will charge.

• Domestic socket (2.4kW): The slowest way to charge electric cars is by plugging them directly into domestic sockets at home. Using this method, it would take 10 hours to charge the average car to 80%.  This is not recommended for fire safety reasons.
• 7kW Fast Charger:These are the most popular choices for home and workplace charging, and as noted above, would take 3 hours and 26 minutes to charge an average car. 
• 22kw Rapid charger: A speedier option that is normally found at service stations, supermarkets and public car parks. This would take 1 hour and 5 minutes to charge the average 40kw electric car.
• Rapid charging point (50kW): Usually found at motorway service stations, these offer even faster charging times for EVs. This would take 29 minutes to charge the average 40kw car
• Ultra-rapid charging point (100kW to 150kW): The fastest method to charge electric cars, with top-up charges taking as little as 10 minutes for certain models. It would take 9 – 14 minutes to charge the average 40kw car, using this method of charging.

Efficiency and Battery Size

Above we gave you the charging times based on an average 40 kWh car, however in reality the battery size of electric cars can vary from as little as 15 kWh to over 100kWh. Larger batteries tend to provide a larger driving range (the number of miles they can cover), but will take more time to fully charge. Smaller batteries will take less time to charge in full, but may have a much shorter range.

The table below outlines how long it would take to charge different electric car batteries from 20% to 80%, using several different speed chargers.

Similar to petrol and diesel cars, an electric car’s efficiency is based on how much energy the car requires in order to travel. A small, energy efficient car will be able to travel a further distance per kilowatt-hour (a unit used to measure energy), and therefore would take less time to charge per mile than a larger, more energy consuming car.  

As well as knowing how long it would take to fully charge your EV, it is worth considering how long it would take to give you ample power to get from A to B.  

The majority of journeys the average driver makes in the UK are under 10 miles. So let’s look at how long it would take to charge your car to give 30 miles range – so you can do a circular journey with ample battery spare.

What is top-up charging?

As the number of electric cars on the roads grow, more and more charging points are popping up in supermarkets and public spaces across the UK. It makes sense to use these to top-up your charge while parked, as this supplements overnight charging. Many workplaces now offer EV charging points too, which is a great opportunity to keep your battery topped up while you’re busy working. If your workplace doesn’t currently have an EV charging point, Pro EV can help to install commercial charging points. 

Why can't electric cars charge faster?

As it stands, it takes significantly longer to charge an electric car’s battery than it does to fill up a petrol or diesel car with fuel. But the technology is still relatively new, and improving all the time.  

Ultra-rapid charging points are already available for certain EV models, such as the Tesla Model 3, with charging times taking from 10 to 20 minutes. 

In the years to come, charging speeds could improve even further.

What factors impact charging speed?

There are several factors that can affect charging speed. These include:

• Battery capacity:The size of your EV’s battery (measured in kWh) will impact its charging speed. The bigger the battery, the longer it takes to fully charge. 
• Remaining charge: How much charge is left on an EV battery will also affect charging time. If you’re charging an empty battery, it will take longer than if you’re topping up a battery that’s already 60% full.
• Type of charger: The speed at which your EV charges also depends on the type of charger used. A home 7kW charger will take longer to charge an EV than an ultra-rapid 100 kW charging station.
• Charging rate of vehicle: Every EV has a different maximum charging rate, meaning you can’t charge them at a faster rate than what’s specified. For example, an EV with a max charging rate of 22kW wouldn’t charge any faster using an ultra-fast 50 kW charging point.
• Colder temperatures: EV batteries take longer to charge when the air temperature is colder, even when using rapid chargers. This may affect the efficiency of your EV and make charging more expensive, as less miles are added per time charging.

Top Tips

• Battery Life: To optimise your EVs battery life, don't let your battery fall below 20% and only charge it up to 80%
• Top-up charging: Charge your EV whenever you park next to a charging point, whether at the supermarket or work. Short bursts of charge also optimises battery life