Understanding Electric Vehicle Charging Times: A Simple Guide

The Key Factors in EV Charging
To calculate an EV's charging time, we need to consider four main factors:
1.Battery Capacity: How much energy can your EV's battery store? (measured in kilowatt-hours or kWh)
2. EV's Maximum Charging Power: How fast can your EV accept a charge? (measured in kilowatts or kW)
3. Charging Station Power Output: How much power can the charging station deliver? (also in kW)
4. Charging Efficiency: How much of the electricity actually makes it into your battery? (typically around 90%)

The Two Phases of EV Charging
EV charging isn't a constant process. It typically occurs in two distinct phases:
1.0% to 80%: This is the fast phase, where your EV can charge at or near its maximum rate.
2.80% to 100%: This is the slow phase, where charging power decreases to protect your

Estimating Charging Time: A Simple Formula
While real-world charging times can vary, here's a simplified way to estimate:
1.Calculate time for 0-80%:
(80% of battery capacity) ÷ (lower of EV or charger max power × efficiency)

2.Calculate time for 80-100%:
(20% of battery capacity) ÷ (30% of the power used in step 1)
3.Add these times together for your total estimated charging time.

A Real-World Example: Charging a Tesla Model 3
Let's apply this to a Tesla Model 3 using our Rocket series 180kW charger:
•Battery Capacity: 82 kWh
•EV Max Charging Power: 250 kW
•Charger Output: 180 kW
•Efficiency: 90%
1.0-80% time: (82 × 0.8) ÷ (180 × 0.9) ≈ 25 minutes
2.80-100% time: (82 × 0.2) ÷ (180 × 0.3 × 0.9) ≈ 20 minutes
3.Total time: 25 + 20 = 45 minutes
So, in ideal conditions, you could expect to fully charge this Tesla Model 3 in about 45 minutes using our Rocket series charger.