Short answer: Your battery's current charge level shown as a percentage, like a fuel gauge for your EV.
Explanation
State of charge is simply your battery percentage. When your car dashboard shows 65%, that means 65% of the usable battery capacity has energy in it. You will see SoC on your car's dashboard, on the charger screen during a session, and in most charging apps.
SoC is important because charging speed changes depending on where your battery percentage sits. Most EVs charge fastest between 10% and 50% SoC, then the speed gradually decreases as the battery fills up. Charging from 80% to 100% can take almost as long as charging from 10% to 80%. This is why most charging advice says to charge to 80% on road trips and move on.
Your car may show a slightly different SoC percentage than the charger screen. This is normal. The car and charger communicate constantly, but they may calculate and display the percentage differently. Trust your car's reading as the primary source.
Where you'll see this
- On the charger screen
- On your car dashboard
- In charging network apps
Common confusion
People often think their car is broken when charging slows down above 80%. This is completely normal. The battery management system reduces power to protect the battery as it fills up.
Example
A Tesla Model Y charges at about 250 kW at 10% SoC, but only about 50 kW at 80% SoC. That slowdown is your BMS protecting the battery.
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