Fondsites Labs
Methodology
Battery Runtime Benchmark Method
A practical runtime method for measuring loads before trusting battery capacity claims.
Method goal
Measure real load behavior and usable runtime under a controlled, safe, repeatable setup.
This page describes a method. It does not claim test results unless results are actually present.
What to measure or document
- Battery model, rated capacity, starting charge, ending charge, and reserve setting.
- Device watts, surge behavior if observed, and hours connected.
- Temperature, inverter mode, and whether loads cycle on and off.
Equipment needed
- Portable power station or home battery display.
- Plug-in watt meter where appropriate.
- Timer or log sheet.
- Only loads that are safe to test under supervision.
Step-by-step method
- Charge the battery according to the manual.
- Connect one known load or a small essentials group.
- Record starting charge, watts, and time.
- Check at regular intervals without leaving unsafe loads unattended.
- Stop at the planned reserve and calculate usable watt-hours.
Data table template
| Battery | Start % | End % | Load | Watts | Hours | Estimated Wh | Notes |
|---|---|---|---|---|---|---|---|
Common mistakes
- Testing a cycling appliance once and assuming it represents every day.
- Ignoring inverter losses, startup surge, and battery reserve limits.
- Using unsafe wiring, extension cords, or generator connections.
Limitations
Runtime varies with temperature, load cycling, inverter efficiency, battery age, and reserve settings.
Electrical safety, medical-device suitability, and permanent wiring need qualified guidance.
This page describes a method. It does not claim test results unless results are actually present.