Question 1

How is charging time calculated?

Accepted Answer

The base formula is `Time = Energy Needed (kWh) / Charger Power (kW)`. The tool calculates the energy needed based on your start and end State of Charge (SoC). It then applies an efficiency factor (since some energy is lost as heat) and simulates a 'tapering' effect for DC fast charging, where charging speed slows down after 80% to protect the battery.

Question 2

How accurate is this charging time calculator?

Accepted Answer

This tool provides a reliable estimate. The calculation is based on the simple formula `Time = Energy Needed / Charger Power`. We add a dynamic buffer to this result to create a more realistic estimate, as it accounts for the natural slowdown in charging speed as the battery approaches full (the 'charging curve') and minor energy losses during transfer. The buffer starts at 15% and increases to ~35% for a 100% charge.

Question 3

What are the main assumptions used in the calculation?

Accepted Answer

The calculator assumes the charger can deliver its rated power consistently and that the vehicle can accept it. In reality, the charging speed can be limited by either the charger's output or the vehicle's maximum intake rate (e.g., a car with a 100kW max charge rate will not charge any faster at a 350kW charger). Our dynamic time buffer helps account for these real-world charging curve effects.

Question 4

Why should I only charge to 80% on a road trip?

Accepted Answer

EV batteries charge much faster at lower states of charge. The charging rate, especially for DC fast charging, slows down significantly after the battery reaches about 80% State of Charge (SoC). This is to protect the battery from overheating and degradation. It is almost always quicker to make two shorter stops charging to 80% than one long stop to charge to 100%.

Question 5

What's the difference between AC and DC charging?

Accepted Answer

AC (Alternating Current) is the type of power from the grid and is used for home and workplace charging (up to 22kW). Your car's onboard charger converts this to DC to fill the battery. DC (Direct Current) is used for public rapid chargers (50kW+) and bypasses the car's onboard converter to charge the battery directly, allowing for much faster speeds.

Cost & Savings

Range & Battery

AI & Insights

Community

Knowledge Hub

Company

Cost & Savings

Range & Battery

AI & Insights

Community

Knowledge Hub

Company

EV Charging Time Calculator

Frequently Asked Questions

About Our Data & Calculations