# What defines the maximum charge a capacitor can store?

The formula for a capacitor discharging is $Q=Q_0e^{-\frac{t}{RC}}$ Where $Q_0$ is the maximum charge. But what property defines the maximum charge a capacitor can store?

If it depends on capacitance then that means it depends on the voltage you put across the capacitor, but how can any capacitor "cope" with any voltage?

The maximum charge a capacitor stores depends on the voltage $V_0$ you've used to charge it according to the formula:
$$Q_0=CV_0$$
However, a real capacitor will only work for voltages up to the breakdown voltage of the dielectric medium in the capacitor. So in reality, for every capacitor there is a maximum possible charge $Q_{max}$ given by:
$$Q_{max}=CV_{max}$$
where $V_{max}$ is the breakdown voltage of the dielectric medium in the capacitor.
• I don't think this answers the whole question. $C$ may be the constant for a given capacitor but there are factors like the surface area of the plates in the capacitor that affect $C$. – Brandon Enright Apr 4 '13 at 23:23