I am using the capacitor in a battery powered device but unable to find the leakage current. They have mentioned the insulation resistance minimum as 10 GOhms.
Can I take this into ohms law to find out the leakage current?
Yes, you can assume R > 10G ohms, so the leakage current is less than Vtest/10G.
You should make sure that the voltage you care about is equal or less than the test voltage the manufacturer uses.
If your circuit is sensitive enough to care about that small a leakage, it will likely be troublesome in other ways.
Yes you can but that would be useless in my opinion. The 10 GOhms is what the manufacturer guarantees, so it can be 20 GOhms but also 100 GOhms.
In general you do not need to worry about capacitor leakage current provided you observe the polarity (for electrolytic types).
In general your battery will have significantly larger internal leakage !
Insulation Resistance is a measure of the ability of the dielectric to withstand the passage of electrons through itself. Insulation resistance is usually expressed as a value of "ohms x farads". Please be sure that whether the given value is "10Gohm.uF" rather than simply 10Gohm. Then you can use these equations to calculate the leakage current. -->
DCL = (Voltage(V))/(Insulation Resistance(IR)) = V/IR
IR = Internal Resistance Spec./Capacitance
Take this example, 47µF commercial X7R MLCCs for power-rail filtering, at a working voltage of 5V. Insulation resistance specification of 500MΩ.µF
IR = 500MΩ.µF/47uF = 10.6MΩ
DCL = 5v/10.6MΩ = .47uA