Battery Bank Sizing Calculator

Determine the right battery bank capacity for your off-grid energy system based on your daily consumption, desired autonomy, and battery type.

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Results

Enter your values and click Calculate to see results.

How Battery Bank Sizing Works

The required battery capacity depends on your daily energy usage, how many days you want to run without charging (autonomy), and how deeply you can safely discharge your batteries.

Required Capacity = (Daily Consumption × Days of Autonomy) / Max DoD

Depth of Discharge by Battery Type

  • Lithium Smart (LiFePO4) — 80% DoD recommended (can handle deeper cycles)
  • AGM / Gel — 50% DoD for longevity
  • Lead Acid — 50% DoD maximum

Lithium (LiFePO4) batteries offer significantly more usable capacity per Ah rating compared to lead-acid alternatives.

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