What is the fastest way to drain all the charges of battery?
I mean can this design is fastest way to discharge it?


No, the current taken by the load resistor gets less and less as battery terminal voltage drops. This is because the effective series resistance of the battery increases as it loses charge (generalism alert!).

So, to discharge safely at the maximum rate you need a constant current load similar to this: -



Vin sets the voltage across Rsense and that determine how much current flows into the BJT collector. 

But you need to ensure that you don't go past the point of no-return for the battery or damage may occur. So, use a comparator to switch off the discharge circuit when the battery terminal voltage reaches the lowest point recommended by the manufacturer.