Charging an Electric Car isn’t as straightforward & easy as filling a petrol/diesel tank. Refuelling a conventional car takes just a few minutes. A driver just has to visit a petrol pump. On the other hand, there’s a list of factors that a driver needs to keep in mind before recharging a car’s battery.

Fully charging an electric car can take as little as a few minutes, or it may take as long as a day. Charging time depends on the type of charging station, car’s battery size, onboard charger capacity, battery status, weather, driving habits, charging habits, etc.

Ignoring some of the lesser variables, let us have a look at the 3 main factors which affect an e-car’s charging time:

1. Type of Charging Station

The time it takes to charge an e-car is dependent on the charging rate of the ChargePoint one is using. AC charging is typically less energy-intensive which makes it much slower. When you charge at home using a conventional plug or a wall box, or even at some public stations, you are using AC. Fast DC charging can be completed in under an hour & is typically found only at public charging stations.

There are three levels of EV charging; Level 1, Level 2 & Level 3. Level 3 is broken into DC Fast Charging & (Tesla) Supercharging. The higher the level of charging, the faster the charging process, as more power is delivered to the vehicle. The typical charging time for a Level 1 charger is 11-20 hrs to fully charge while the Level 2 charger takes around 3-8 hrs. DC fast charging takes up to an hour & Tesla Superchargers take 40 mins.

2. Battery Size

The bigger your car’s battery capacity (measured in kWh), the longer it will take to charge. Battery manufacturers are trying hard to reduce the charging time and make it possible to charge a battery pack as fast as possible.

The battery capacity differs for each car. The Nissan Leaf, for example, has a battery capacity of 40 kWh, while the Tesla Model S has a capacity of 75 kWh. Using a 7 kW charging point for both the cars gives a 0-100% charge for the Leaf in 6 hrs & the Tesla in 11 hrs.

But this viewpoint is very narrow as it ignores a huge factor involving the onboard charger capacity which totally turns the tables when it comes to rapid charging.

3. On-Board Charger Capacity

You can only charge a car’s battery at the maximum charge rate the car can accept. There’s an onboard charger in e-cars that convert AC electricity into DC to charge the battery. On-board chargers trickle power into the battery pack and have their own power ratings (in kW).

For example, a Tesla Model 3 has an 11.5 kW charger & an 80.5 kWh battery, which would take roughly 7 hours to charge fully. However, the typical electric vehicle offers a standard 6 kW charger, which would more than double that car’s charging time.

Tata Motors is understood to have consciously restricted the onboard charger’s capacity to 3.2kW instead of a higher rating, for instance, 7.2kW, as customers would then need a three-phase AC supply, which is not readily available across India.

On the other hand, in Europe, Mercedes Benz has upgraded the 7.4 kW charger in its EQC electric SUV to an 11 kW one since more-and-more public charging stations in Europe are upgrading to 11-22 kW grid connection. This will considerably decrease the EQC’s charging time.

You’ll also experience slower charging when the weather is cold.

Tesla Supercharger Network:

A broad network of proprietary charging stations developed & implemented by Tesla, the Supercharger network was introduced in September 2012. Superchargers aren’t called super for nothing; these ultra-powerful 480-volt charging stations allow Tesla owners to charge their car in under an hour.

Tesla has been working aggressively on its India debut plans. While the electric vehicle manufacturer is yet to come out with an official timeline of its first product launch, several vehicles were spotted testing in real-life road conditions in India. Tesla’s supercharger was also reportedly spotted in India for testing purposes.

Conclusion:

Manufacturers will someday settle on a single metric for expressing charging times. But for now, charging an EV's battery still takes considerably longer than refuelling a conventional car's fuel tank no matter how or where you do it.

Israeli company StoreDot has begun production of its extreme fast-charging (XFC) batteries. StoreDot’s aim is for these batteries to be able to gain 100 miles of charge in only 5 minutes by 2025. That’s twice as fast as a 150kW charger can manage today. They have attracted investment from Daimler & BP.

In 5 to 10 years, though, far faster charging might be possible. Companies are developing new lithium-ion battery prototypes, as well as new “solid-state” batteries, which are more stable at faster-charging speeds. They could place recharge rates of 10-20 minutes or less within reach.