“How long does it take to charge an EV?” is one of the most common questions posed by both potential and current EV owners as EVs gain popularity. Giving a set number of hours isn’t the only way to answer the question. The time required to charge an EV is actually something that can fluctuate based on several different factors, battery capacity being perhaps one of the most essential of these.
Both daily users and fleet operators must understand the relation between the charging time of an EV and the size of its battery. Planning, efficiency, and user experience will all be affected regarding how the battery capacity of your EV relates to its charging time, whether at home, on the way to your destination, or while managing a commercial EV fleet. In the next section, we take a detailed look into the strength of this relationship and also share some recommendations to improve your charging practice.
Understanding Battery Capacity
Battery capacity expresses the amount of energy the battery can store and is given in kilowatt-hours (kWh). In simpler terms, it is much equivalent to the fuel tank size of a gasoline or diesel vehicle. A bigger battery can store more energy, which generally translates into a longer driving range but longer EV charging times too.
For example, the Hyundai IONIQ 5 boasts a sizable 72.6 kWh battery, the MG ZS EV has a 50.3 kWh battery, and the Tata Nexon EV has a 30.2 kWh battery. If everything else is equal, a larger battery will take longer to fully charge.
It’s crucial to remember that EV charging time is not solely determined by battery size. The maximum acceptance rate of the vehicle and the charger’s power output are also important factors. However, battery capacity is a key indicator of how EV charging times will differ when comparing EVs.
EV Charger Types and Power Output
The charger type has a significant impact on how long it takes to charge an EV. The four primary charger types and their effects on EV charging time are broken down as follows:
Level 1 AC (2.5 kW Standard Home Socket)
Incredibly slow
Increases range by about 8–10 km per hour.
Only appropriate for small battery EV overnight home charging
It takes about 16 hours to charge a 40 kWh battery
Level 2 AC (7.2 kW, wall box or pole-mounted)
A moderate pace
Increases range by 25–30 km per hour
Ideal for installations at home or at work
A 60 kWh battery takes about 8 to 9 hours to charge
50 kW DC Fast Charging
Options for rapid charging at public stations
Takes about 50 minutes to charge 20–80% of a 50 kWh battery.
Perfect for en route or highway top-ups
Ultra-Quick DC Charging (above 150 kW)
Primarily for high-end EVs, advanced chargers
Takes 20 to 25 minutes to charge 80% of a 70 kWh battery
To prevent overheating, thermal battery management is required
Optimizing EV charging time and preventing needless delays requires knowing which charger is appropriate for your EV’s battery capacity.
Comparison Table: Charger Type vs EV Charging Time
| Charger Type | Output Power | 30 kWh Battery | 50 kWh Battery | 70 kWh Battery |
|---|---|---|---|---|
| Level 1 AC | 2.5 kW | ~12 hrs | ~20 hrs | ~28 hrs |
| Level 2 AC | 7.2 kW | ~4.2 hrs | ~7 hrs | ~9.8 hrs |
| DC Fast Charger | 50 kW | ~36 mins | ~60 mins | ~84 mins |
| Ultra-Fast DC Charger | 150 kW | ~12 mins | ~20 mins | ~28 mins |
Understanding which charger suits your EV’s battery capacity helps optimize EV charging time and avoid unnecessary delays.
How to Determine Charging Time
The following is the fundamental formula for calculating EV charging time:
Battery Capacity (kWh) ÷ Charger Output (kW) = Charging Time (in hours)
This calculation is theoretical, though. Let’s use it in a few actual situations:
- A Tata Nexon EV powered by a 7.2 kW AC charger and a 30.2 kWh battery:
→ EV charging duration = 30.2 ÷ 7.2 ≈ 4.2 hours
- An MG ZS EV using a 50 kW DC fast charger and a 50.3 kWh battery:
→ EV charging duration = 50.3 ÷ 50 ≈ 1 hour
- With a 72.6 kWh battery and a 150 kW ultra-fast charger, a Hyundai IONIQ 5:
EV charging duration = 72.6 ÷ 150 ≈ 29 minutes
Keep in mind that most EVs don’t charge consistently. For example, in order to preserve battery health, fast charging usually occurs up to 80% capacity before decreasing. EV charging time can rise disproportionately above 80% due to this tapering effect.
Additionally, drivers hardly ever charge between 0% and 100%. In practice, EV charging times are shortened because most real-world charging is carried out in steps, such as 20% to 80%.
Factors in the Real World That Impact Charging Speed
In the real world, EV charging time is influenced by a number of factors, even with conventional chargers and specified battery capacities:
1. Health of the Battery
Batteries that are older or subjected to harsh environments may charge more slowly. Degradation of batteries can impact energy absorption efficiency, extending the time needed for EV charging.
2. The temperature of the surroundings
The ideal temperature range for batteries is between 20 and 25°C. Because lithium-ion cells have internal resistance, EV charging times may lengthen in colder climates.
3. Limitations of the Onboard Charger
There is a maximum charging acceptance rate for every EV. EV charging will take longer than anticipated if the EV’s onboard system only supports 11 kW, even if the charger has a 22 kW capacity.
4. The Charging Curve
The rate of charging is not constant. The majority of EVs charge quickly from 0 to 80% and more slowly in the final 20% to preserve the battery. This makes figuring out how long it takes to charge an EV more difficult.
Managing expectations and effectively organizing charging sessions require an understanding of these factors.
Top Techniques for Improving Charging Time
Use these wise tips to get the most out of your EV and cut down on charging time:
- Charge at Home Overnight: Make sure your EV is prepared every morning by using Level 2 AC chargers. Overnight charging provides consistent EV charging time and coincides with grid-friendly hours.
- Plan Long Trips Around Fast Chargers: To prevent last-minute stops and EV charging time delays, use navigation apps that display charger types and locations.
- Steer clear of frequent 100% charges as this can harm batteries and lengthen the time needed for long-term EV charging. Performance is maintained by adhering to 20–80% cycles.
- Precondition Battery: Preconditioning, or warming the battery before charging, helps cut down on the amount of time needed to charge an EV in the winter in colder climates.
These practices extend battery life in addition to saving time.
Prospects for the Future
It appears that EV charging times will become more intelligent and efficient in the future. A number of innovations are imminent:
- AI-Based Charging Optimization: To provide the quickest and least expensive charging possible, intelligent systems will evaluate your schedule, battery condition, and grid load.
- Solid-State Batteries: By enabling higher energy densities and quicker thermal management, these next-generation batteries promise a significant reduction in EV charging time.
- Bidirectional Charging (V2G): As Vehicle-to-Grid (V2G) becomes more popular, EVs will quickly charge as well as release energy back into the grid, changing our perception of EV charging duration and consumption.
Everyone will find EV charging faster, more intelligent, and more convenient as a result of the convergence of technological innovation, infrastructure advancements, and user awareness.
In conclusion
To maximize the effectiveness and usefulness of electric vehicles, it is crucial to comprehend how battery capacity and EV charging time interact. The battery size has a direct impact on how and when you charge, regardless of whether you drive a luxury SUV or a small city EV. EV users can significantly enhance their EV charging experience by selecting the appropriate charger, understanding practical considerations, and implementing best practices. Expect even faster EV charging times and more intelligent solutions as technology develops, making the EV lifestyle more affordable and environmentally friendly than it has ever been.