Battery energy runtime
Estimate runtime from rated energy, usable fraction, and steady load.
How this works
Runtime = rated Wh × usable fraction × efficiency / load watts.
Example
Using the example inputs, estimated runtime is 6 hours.
- Rated battery energy
- 500 Wh
- Usable energy fraction
- 80 %
- Delivery efficiency
- 90 %
- Constant load
- 60 W
- Estimated runtime
- 6 hours
Scope and assumptions
Approximate energy budget, not wiring, charging, discharge-current or battery-safety advice. Temperature, aging and cutoff behavior affect runtime.
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