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Power & Battery

Battery Life & Runtime Calculator

Estimate real-world operating time of battery powered systems factoring in discharge derating.

Lab Gear (Amazon (voltcraft-20))

USB-C Intelligent Li-ion 18650/21700 Battery Charger & Capacity Tester

Tested and recommended for reliable hardware prototyping and accurate measurements.

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Formula & Theory

T = \frac{\text{Capacity} \times \eta}{I_{load}}

Frequently Asked Questions

Q: Why apply an 85% discharge factor?

Chemical batteries suffer from self-discharge, voltage sag, and temperature variations, rarely delivering 100% rated capacity.