Don't buy cheap cordless drills for occasional use, the batteries will die after a couple of years. I have casually tested plenty of cheap Chinese Li-ion cells, they fail rapidly and reliably.
Don't buy expensive cordless drills for occasional use, the cost of high quality Li-ion packs is a silly way to spend money.
Again: Don't give advice in areas that you clearly have no experience with. Leave the University of Google stuff to Arrynfield, it just makes you look foolish at best, and at worst results in someone wasting time, money, or blowing up equipment.