calc.engineer / Solar & Power / Battery Life

Battery Life v1.0.0

Calculates battery runtime and energy capacity given cell capacity in mAh, nominal voltage, and average current draw. Accounts for real-world discharge efficiency (Peukert-adjacent derating) to produce effective capacity, total energy in Wh, and runtime in hours and days. Useful for IoT sensor node planning, portable device design, UPS hold-up estimation, and solar battery bank cycling analysis. Outputs feed into solar_sizing (battery_kwh) and ups_runtime (battery_wh) for system-level calculations.

feeds solar_sizing →feeds ups_runtime →
Battery capacity in milliamp-hours (mAh)
Nominal battery voltage (V), default 3.7 for Li-ion
Average current draw in milliamps (mA)
Discharge efficiency factor (0-1), accounts for conversion losses and derating, default 0.85
Fill in the inputs and Compute to see the structured result.

From an agent (MCP) or the API

curl -X POST https://calc.engineer/api/battery_life \
  -H "Content-Type: application/json" \
  -d '{"capacity_mah": …, "voltage": …, "current_draw_ma": …}'

MCP: connect to https://calc.engineer/mcp and call battery_life.

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