A standard hand drill with good power is required to screw the fence rails to the posts and for the construction of a gate. If you use a rechargable, you are going to need a very high powered drill. The treated wood that the fence posts are made of require a large screw and much force to drive the screws. Small drills may not be up to the duty. Electric cord drills tend to have much greater power so stick with these if a power supply is available.
Don’t Forget The Driver Set
A driver set will be needed to convert the drill into a powered screw driver. I suggest a high quality set because of the high amount of force used to drive the screws into treated wood.