calculators
Battery Capacity Calculator
Estimate required nominal battery capacity from load, runtime, depth of discharge, efficiency, and optional system voltage.
Frequently Asked Questions
How is capacity calculated?
Required nominal Wh = load W x hours / (depth of discharge x efficiency). Required Ah = required Wh / system voltage.
Should I include depth of discharge?
Yes. Depth of discharge changes the nominal battery capacity needed for the same usable energy target.
What voltage should I use?
Common small system voltages are 12V, 24V, and 48V. Higher voltage usually means lower current for the same power.