A cordless drill is a type of electric drill which uses rechargeable batteries. These drills are available with similar features to an AC mains-powered drill. They are available in the hammer drill configuration and most also have a clutch setting which allows them to be used for driving screws. Also available now are Right Angle Drills, which allow a worker to drive screws in a tight space. These are currently less useful than the corded version however, as one of the main functions is drilling holes through joist and studs to run electrical and plumbing. While recent battery innovation allows significantly more drilling, the large diameter holes required (typically 1/2"-1" or larger) drain current cordless drills quickly.

 

For continuous use, a worker will have one or more spare battery packs charging while drilling, so that he or she can quickly swap them, instead of having to wait an hour or more for recharging, although there are now Rapid Charge Batteries that can charge in 10-15 minutes.

 

Early cordless drills started with interchangeable 7.2 V battery packs, and over the years available battery voltages have increased, with 18 V drills being most common, and 24V drills are available. This allows these tools to produce as much torque as some mains-powered drills. The drawback of most current models is the use of nickel-cadmium (NiCd) batteries, which have limited life, self-discharging and eventually internally short circuiting due to dendrite growth. This severely limits battery life, and poses a hazardous materials disposal problem. A lot of drill manufacturers, including DeWalt, Ryobi, and RIDGID, are now using lithium ion batteries. The main advantages are very short charging time, longer life, and lighter battery weights. Instead of charging a tool for an hour to get 20 minutes of use, 20 minutes of charge can run the tool for an hour. Lithium-ion batteries also have a constant discharge rate. The power output remains constant until the battery is depleted, something that nickel-cadmium batteries also lack, and which makes the tool much more versatile. Lithium-ion batteries also hold a charge for a significantly longer time than nickel-cadmium batteries, about two years if not used, vs. 1 to 4 months for a nickel-cadmium battery.

 

The handles of cordless drills are usually made from polymorph which is easy and quick to mold to a comfortable shape for holding. The main body of the drill is usually made from polythene as it is able to withstand the high temperatures which the drill reaches.Plus it cuts wood,metal and plastic.