whatever way around it is the higher AH means i can drill out a lock without the battery going flat on the first hole , a 15.6v 3.5ah hilti drill will drill much more than an 18v 1.7ah dewalt with the dewalt not having the torque behind it to manage 22mm or higher auger bits.
you get cheap b+q drills for £30 that are allegedly 18v but dont have the power to screw a single 100mm screw home.
but you pay the price for that at the checkout with the best stuff costing £250-£350.