Question 1

How is battery energy measured?

Accepted Answer

Watt-hours (Wh) or milliamp-hours (mAh) × voltage. A 3000 mAh battery at 3.7V = 11.1 Wh.

Question 2

What is battery capacity vs energy?

Accepted Answer

Capacity (mAh) is charge. Energy (Wh) = capacity × voltage. Compare Wh for batteries at different voltages.

Question 3

What's the difference between energy and power?

Accepted Answer

Energy (joules, kWh) is total work done. Power (watts) is energy per unit time. A 100W bulb for 10 hours = 1 kWh of energy.

Question 4

Why are there so many energy units?

Accepted Answer

Different fields developed their own: BTU for heating, calories for nutrition, joules for physics, kWh for electricity billing.

Battery Energy Converter

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