Short answer: A unit measuring electrical pressure that pushes current through the charging cable and into your battery.
Explanation
Voltage is the electrical pressure that drives current through a circuit. Think of it as water pressure in a pipe. Higher voltage pushes more energy through the same cable, enabling faster charging without needing thicker wires. In Europe, your home outlet runs at 230 volts, while DC fast chargers operate at 400 to 1000 volts.
You see voltage on charger screens during DC fast charging, and sometimes on your car's dashboard in the charging details. Most EVs today use either a 400V or 800V battery architecture, and this directly affects how fast they can charge.
The voltage at the charger must match what your car can accept. A 400V car plugged into an 800V charger will still charge, but at 400V, which limits the maximum current and therefore the peak speed. This is why 800V cars like the Hyundai Ioniq 5 and Porsche Taycan can charge faster than most 400V cars at the same station.
Where you'll see this
- On the charger screen
- On your car dashboard
- In vehicle specifications
Common confusion
Some people think voltage alone determines charging speed, but speed depends on voltage multiplied by current (amps). A charger might show high voltage but limited amps, resulting in moderate power.
Example
A Porsche Taycan operates at up to 800V and can accept up to 270 kW. A Renault Zoe operates at around 400V and maxes out at 50 kW DC.
Related terms
See a term you don't recognize? Scan it.
Point your phone at any charger screen. Coming soon.
Stuck at the charger? Open the app.
Step-by-step help for real charging problems. Log the experience. Free on iOS and Android.
Free to download · Available on iOS and Android