Many 14.4-volt drill/drivers pack all the power you need for a wide variety of chores. And higher-voltage drills can cost little more than less capable, lower-voltage models.

Battery packs with higher voltage and capacity allow today's cordless models to run longer and more powerfully per charge. The best can outperform corded drills and handle decks and other big jobs with minimum battery recharging. Recent tests also show that you don't have to spend $200 or more to get very good performance. Models in the 14.4- to 18-volt range that cost as little as $110 perform nearly as well as the most expensive drills.

You'll also see more impact drivers. While similar to conventional drill/drivers, impact drivers emphasize added tightening and loosening power, courtesy of a spinning internal hammer that strikes an anvil attached to the chuck to boost twisting force. Besides being lighter and smaller (most use 12- or 14.4-volt batteries), impact drivers don't twist in your hands under load. But they tend to be slower at drilling and require special drill bits for that task. Those we've tested have also been loud enough to require hearing protection.

WHAT'S AVAILABLE

Black & Decker and Craftsman (Sears) are the major brands. Along with Ryobi and Skil, they're aimed primarily at homeowners. Bosch, DeWalt, Hitachi, Makita, Milwaukee, Ridgid, and Porter-Cable offer pricier drills designed for professionals.

Most 9.6-volt models cost less than $100. At about three pounds, they weigh half as much as some 18-volt models. But unless you value low weight and low cost over performance, you're likely to be disappointed with a 9.6-volt drill. Many 12- and 14.4-volt models also sell for less than $100, and are more capable.

Price ranges: Figure on 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 about $100 to $300 for 18-volt models.

Cordless impact drills are made by the same manufacturers who make conventional drill/drivers. While many cost $200 or more, you'll find capable models for around $100.

IMPORTANT FEATURES

A "smart" charger recharges a drill's battery in about an hour or less, compared with three to five hours or more for a conventional charger. Smart chargers also extend battery life by adjusting the charge as needed. Most smart chargers switch into a maintenance or "trickle-charge" mode as the battery approaches full charge. One drill has a dual charger that charges two batteries at once.

Most cordless drills 12 volts and more have two speed ranges: low for driving screws, high for drilling. Low speed provides more torque, or turning power, than the high-speed setting, which is useful for drilling holes. Most models also have a variable speed trigger, which can make starting a hole easier, and an adjustable clutch, which lowers maximum torque to avoid driving a screw too far into softwood or wallboard, or mangling its head.

Most drills have a 3/8-inch chuck, but some higher-voltage models have a 1/2-inch chuck, which can accommodate drill bits up to 1/2 inch. (Large diameter bits with a reduced shank will fit in smaller chucks.) Today's models are also reversible, letting you more easily remove a screw or back a drill bit out of a hole.

Still other features make some drills easier to use than others. Some models have a second handle that attaches onto the side of the drill so you can use two hands for better control when driving large screws, for example. All but the least expensive drills come with two batteries, letting you use one while the other charges.

Most cordless drills run on nickel-cadmium (NiCad) batteries, which can be recharged hundreds of times. Once they're depleted, though, NiCads must be recycled, since cadmium is toxic and can leach out of landfills to contaminate groundwater if disposed of improperly. Incineration can release the substance into the air and pose an even greater hazard. A few models run on nickel-metal-hydride (NiMH) batteries, which don't contain cadmium and are friendlier to the environment. In recent tests, Consumer Reports found that some NiMH-powered models ran longer than many 18-volt and 14.4-volt NiCad-powered models, yet weighed about the same.

Some drills are bundled with other cordless tools and sold as kits. The package typically includes a circular saw, a reciprocating saw, and--often--a flashlight and carrying case. Some kits are a relatively good deal. But as our reports have shown, cordless circular saws tend to be far weaker than corded models. And some kits are merely a collection of mediocre tools.

HOW TO CHOOSE

High value in the 14.4- to 18-volt category means there's little reason to buy a 12- or 9.6-volt drill/driver. You won't save much money, and power and run time are lower. You'll also find lower-voltage drills that combine ample drilling and screwdriving power for larger household projects without being too heavy for smaller ones.

Determine how much voltage you're likely to need for the drilling and screwdriving tasks you do most. Then ask yourself these questions while you're shopping for a new drill:

Are high-end brands worth it? High voltage isn't the only mark of a capable drill. You can purchase an 18-volt drill with a 1/2-inch chuck for thicker bits, versus the usual 3/8-inch chuck, letting you drill larger holes. But you may not want to pay the $200 or more typical for most cordless drills with that feature if your home to-do list doesn't include larger projects or heavier-duty drilling.

How much are replacement batteries? A cordless drill's battery can be discharged and recharged roughly 500 times before it must be replaced. While batteries can last five years or more, frequent use can deplete them sooner. At $20 to $80 each for many of the batteries that power drills, replacing them can cost as much as buying a new cordless drill.

Battery replacement may be less of a concern if you're buying a $250 drill you plan to keep for a while. And for models that cost less than $100, simply replacing the drill may make more sense than buying a new pair of batteries. Otherwise, consider battery cost along with the drill.

Are you buying other cordless tools? You're likely to be tempted by multi-tool kits, which cost far less than you'd pay for the tools separately, since the tools in each kit are powered by the same batteries and charger. But these kits can be less of a bargain than they seem; performance of some of the tools they include, particularly circular saws, has been mediocre in our tests, and you may not use all of them.

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