Everything you need to know about estimating your electric vehicle’s charging time.
An EV’s charging time depends on two major factors: how much charge (kWh) is needed, and how much power (kW) the EV charging station provides. Divide the charge needed by the power provided to get the estimated hours of charge time required.
A Tesla Model 3 with an 80 kWh battery size parks at a 7.68 kW Level 2 charging station with 20% battery left. They would like to charge their EV to 80%.
Find charge needed in kWh:
80% – 20% = 60% needed
80 kWh (battery size) x 0.6 (charge needed) = 48 kWh needed
The temperature of your EV battery can significantly affect charging speed. While most EVs are equipped with thermal management systems to help regulate battery temperature, extreme cold and heat can still slow down a charge. A slower charge in extreme temperatures helps preserve battery health, maintain performance, and ensure safety.
There are three primary levels of EV chargers, each offering different power levels that impact charging speeds:
Some charging stations support load sharing or load management technology, which distributes available electrical power across multiple vehicles charging simultaneously. This distribution can be done equally to all charging vehicles, or on a first-come, first-served basis. Both methods can lead to extended charge times for users. However, these distribution systems are essential for many properties to ensure power usage stays within the grid’s limitations.
Each EV has a maximum charging rate, which is the highest amount of power a vehicle can pull from a charger at a given moment. For instance, plugging into a 50 kW fast charger doesn’t ensure your vehicle will charge at that speed, it can only draw as much power as it’s designed to handle. Some EVs allow you to manually adjust this rate, while others may have lower limits set automatically to help preserve long-term battery health.
Over time, EV batteries may begin to lose some of their ability to hold and utilize charge, a process known as battery deterioration. Factors such as battery age, frequent use of DC fast charging, and exposure to extreme temperatures can accelerate this process. A deteriorated battery will take longer to charge and provide less range than when it was new.
State of charge indicates how full your EV battery is. Charging doesn’t happen at a constant speed, it’s faster when the battery is low and slows down as it approaches full capacity. This is why charging from 10% to 80% is often quicker than topping off from 80% to 100%. This tapering process helps protect the battery but can increase total charging time if aiming for a full charge.