You probably shouldn’t try this, but it’s nice to know you can in a pinch. Your car battery is dead and you like a boost to jump start? Maybe you can use AA batteries to crank the engine…, While the internal resistance of a car battery can be less than 10 mOhm, the resistance of a AA battery is around 250 mOhm. This means if you draw 2 A from the battery, its voltage drops by 0.5V out of its total 1.5V.