0Jack A Lopez 4 years ago Meany, meany, miney, mah.Catch a tagger by its tah.If it hallah, let it gah.;-)Seriously though, capacitors and batteries are not exactly the same thing, so there is not an obvious conversion between the units of,current capacity, or charge, 1 ma*h = (10^-3 A)*(3600 s) = 3.6 A*s = 3.6 C= 3.6 ampere*seconds = 3.6 coulombs, used for rating the current capacity of a battery,versus capacitance, a ratio of charge (on a capacitor) to voltage (measured across the same capacitor). The SI unit for capacitance is the farad, F.1 F = (1 C)/(1 V)1 farad = (1 coulomb)/(1 volt)The actual amount of charge stored on a 1 microfarad capacitor, at ordinary voltages, e.g. 10 volts or 20 volts, the actual amount of charge is small.Q = C*V = (1 uf)*(10 V) = 10 uC = 10 microcoulombs = 10 uCQ = C*V = (1 uf)*(20 V) = 10 uC = 20 microcoulombs = 20 uCA comparison in terms of energy maybe makes more sense, and other answerers here have mentioned this.The usual naive calculation for energy in a battery is just the current capacity multiplied by the battery voltage, e.g. for a 10 or 20 volt battery with a current capacity of just 1 ma*h,U = (1 ma*h)*(10 V) = (10*3.6 C)*(10V) = 36 JU = (1 ma*h)*(20 V) = (10*3.6 C)*(20V) = 72 JEnergy stored in a capacitor depends on the square of the voltage, as the formula, U = 0.5*C*V^2So, for example, a 1 uF capacitor, charged to a voltage of 10 V, or 20 V, has stored energy:U = 0.5*C*V^2 = 0.5*(1 uF)*(10 V)^2 = 50 microjoules = 50 uJU = 0.5*C*V^2 = 0.5*(1 uF)*(20 V)^2 = 200 microjoules = 200 uJSo it kind of looks like a 1 ma*h battery beats a 1 uF capacitor, by a factor of roughtly a million = 10^6, in terms of energy storage, at ordinary voltages, 10 or 20V or so.I mean the numbers might get better at higher voltages, like 100s or 1000s, of volts, since there's that dependence on voltage squared, but you know that might be problematic too, because high voltage things tend to be dangerous.