Hidden Buffer & “Zero” Is Not Actually Empty
- Almost every EV reserves a small amount of energy below the 0% gauge reading (“floor buffer”) so you can’t truly run the cells to zero and damage them.
- When your dash shows 0%, you still have maybe 2–4 miles of “hidden” range—enough to limp to a charger or a safe place to stop.
Car’s Behavior at 0%
- Limited performance warnings: “Low battery” alerts and a forced “limp” mode that reduces power output and turns off non-essential systems (heated seats, aggressive acceleration) to conserve what’s left.
- Automatic shut-off: Once that hidden buffer is consumed, propulsion shuts down entirely—you cannot continue driving. Lights, climate, and infotainment usually go dark too, though some residual capacity may keep hazard flashers or minimal lighting alive for a short time.
Why Draining That Buffer Is Bad
- Pushing cells to their absolute minimum voltage can harm long-term battery health, causing cell imbalance or irreversible capacity loss.
- The battery management system (BMS) enforces the buffer and won’t let you drive “until empty” in the literal sense.
What to Do If You Reach 0%
- Plan ahead: Treat the “0%” reading as your signal to stop for a charge immediately—don’t count on that hidden few miles.
- Roadside assistance or tow: If you run completely out of energy, you’ll need a tow or mobile charger to reach a proper station.
When the indicated state-of-charge hits zero, you still have a tiny reserve but once that’s gone the car will not let you drive any further. Treat “0%” as your final warning to plug in.