Calculators and formulas for calculating the battery capacity
This function calculates the capacity of a battery and the relationship between capacity, energy and voltage.
To perform the calculation, use the radio button to select which value should be calculated. Then enter the required values and click the 'Calculate' button.

The unit of measure of energy is watt hours(Wh) or kilojoules (kJ)
\( 1\; Wh = 3,6\; kJ \)
The unit of capacity is milliamp hours (mAh) or coulombs (C)
\( 1\; mAh = 3,6\; C \)
The unit of measurement for voltage is the volt (V)
\(\displaystyle energy= capacity · voltage\) \(\displaystyle E= C · U\)
\(\displaystyle capacity =\frac{energy}{voltage}\) \(\displaystyle C= \frac{E}{U}\)
\(\displaystyle voltage =\frac{energy}{capacity}\) \(\displaystyle U= \frac{E}{C}\)
