Lithium-ion (Li-Ion) and nickel-metal-hydride (NiMH) batteries are helping cordless drills add power and run time, with less weight for Li-Ion.

Greener design is also a plus, since Li-Ion and NiMH batteries don't contain toxic cadmium, which can leach into groundwater if spent nickel-cadmium (NiCd) batteries are thrown out with trash instead of recycled.

While most drills with these new-tech batteries still sell for $200 or more, you'll find more lower-priced models as more brands make the switch. At as little as $100, however, capable NiCd drills still cost far less. You’ll also see more impact drivers, which emphasize tightening and loosening power over speed, courtesy of a spinning internal hammer. But their striking action makes them loud enough to require hearing protection.

WHAT’S AVAILABLE

Black & Decker and Craftsman (Sears) are the major brands; like Ryobi and Skil, they’re aimed primarily at homeowners. Bosch, DeWalt, Hitachi, Makita, Milwaukee, Porter-Cable, and Ridgid offer pricier drills designed for pros and serious do-it-yourselfers. Most 9.6-volt models cost less than $100; at about 3 pounds, they weigh half as much as some 18-volt models, the typical voltage these days. You’ll even find small, lightweight Li-Ion drills in that price range. But unless you’re handling strictly light-duty tasks, you’re likely to be disappointed with most sub-$100 drills. Price: about $40 to $100 for 9.6-volt drills, $50 to $130 for 12-volt drills, $60 to $200 for 14.4-volt models, and $100 to $300 for 18-volt models; $150 or more for most impact drivers.

IMPORTANT FEATURES

A "smart" charger recharges a drill’s battery in 15 to 60 minutes, compared with three to five hours or more for conventional chargers. They also extend battery life by adjusting the charge as needed. Some models have a dual charger that charges two batteries at once, and a battery meter that shows remaining charge while in use. Many cordless drills have two speed ranges: Low for driving screws with added torque, high for drilling with added speed. Low speed provides more torque, or twisting, force. Most also have a variable speed trigger to make starting holes easier, and an adjustable clutch for lowering maximum torque to avoid driving a screw too far into softwood or wallboard. And all are reversible. Most drills have a 3⁄8-inch chuck, but some higher-voltage models have a 1⁄2-inch chuck for drill bits up to 1⁄2-inch. (Large-diameter bits with a reduced shank will fit smaller chucks.) Some models have a hammer mode that pulses the chuck and bit forward and back to punch through masonry. Some have a second handle that attaches to the side for two-handed drilling. All but the least-expensive drills come with two batteries, letting you use one while the other charges.

Some drills are bundled with other cordless tools and sold as kits that typically include circular and reciprocating saws, a flashlight, and a carrying case. Some kits are a relatively good deal, while others are a collection of mediocre tools.

HOW TO CHOOSE

Not everyone needs maximum power and run time; nearly any drill will do for hanging pictures and other easy tasks. Most lighter-duty drills are lighter in weight. Decide how much speed and power you need. Then keep these tips in mind:

Don’t go by voltage. Several 18-volt drills were bested by models with 14.4 and even 12 volts.

Check battery prices. Some NiCd replacement cells cost as little as $25 compared with $90 or more for many Li-Ion and NiMH cells. While you can’t share batteries between brands, some let you buy their 18-volt drills, saws, and other tools with or without batteries and chargers, letting you build a collection à la carte for less.

Put your hands on it. Besides checking a drill’s weight, check its balance by gripping it firmly and then lifting it to the wall as if you were about to drive a screw. The drill’s chuck should point straight ahead and not tilt up or dip down.

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