A giant leap forward in battery and charger design, Lithium Ion (Li-Ion) technology powers the newest generation of cordless tools, and it’s more than marketing jargon on the box. Compared with its predecessors, Nickel Cadmium (NiCd) and Nickel Metal Hydride (NiMH), the Li-Ion platform delivers more power and lasts longer yet weighs less. It even holds a charge better between uses.
There’s a lot to like about this technology, and because it’s more versatile than NiCd, it’s being used to power many different tools — already on the shelves and soon to be released. Here’s how your shop can benefit from the Li-Ion power boon.
Li-Ion’s advantages
Some tool users think of power as the ability to countersink a deck screw, hog through a joist or chip concrete, whereas others view it as the ability to set lots of screws, make miles of cuts or drill a zillion holes on a single charge. Li-Ion tools offer the best of both — brute force and endurance — more effectively than any other cordless platform, taking us a broad-jump closer to a fully cordless worksite and shop.
Nevertheless, Li-Ion is technically no more powerful than NiCd. Although different platforms use cells of different sizes, the measure of power — volts — is the same. Any 18-volt battery delivers 18 volts; the difference is in the size of the package. Li-Ion is essentially a higher-capacity fuel than NiCd. It delivers the same amount of force yet takes up less space.
Because of their chemical composition and advanced monitoring circuitry that protects them from overcharging, over-draining and heat, Li-Ion batteries operate for a longer time. In addition, the power-delivery profile for Li-Ion batteries is more even than for NiCd and NiMH. You know what it feels like when your battery starts to fade at the end of the charge: Screws take a little longer to set, holes are a little tougher to drill and saws bog down. But Li-Ion tools offer constant power (which some companies call “fade-free performance”) from the first cut to the last.
If you’re using these tools in heavy-duty applications — building a deck, cutting plywood, fastening lots of drywall — this is a real boon to production because you don’t have to swap out batteries nearly as many times during a project. And if you’re using the tools only occasionally, the batteries don’t lose their charge, so you can pull a tool out of its box and get right to work. Manufacturers are also claiming that Li-Ion batteries have incredible cycle life (the number of times you can charge and discharge a battery before it’s spent). NiCd batteries can be charged about 450 times, depending on use. But Li-Ion batteries can be charged 1,500 to 2,500 times. This enormous improvement increases the amount of time — and the number of projects — for which a tool is useful.
There’s more good news if you’re investigating an upgrade to Li-Ion tools: The tools themselves have been improved. One almost universal upgrade involves the battery pack. Because of how Li-Ion cells are bundled and their on-board usage circuitry, they slide on. Their lack of stems has allowed manufacturers to design better battery-release tabs.
Now for the bad news: Li-Ion tools cost more. And because they’re new to the market, they often come only in kits. With a little hunting or special-ordering you may be able to find a single tool and save money initially, but kits seem to offer the most bang for the buck because you get both tools and batteries in one package. As more tools enter the production pipeline, as the technology proves itself in the market, and as users’ older tools wear out, more kits — some larger, some smaller — are providing more choices.
For buyers who aren’t ready to make a major switch, several companies offer Li-Ion tools that are backward-compatible with other battery platforms, so you can buy a tool-battery combo and use your old NiCd batteries with the new tool. Or you can upgrade to Li-Ion batteries and use them in existing NiCd tools. Compatibility features vary according to the brand of tool you choose.
Buyers’ choices
Li-Ion’s higher output enables manufacturers to pack more power into smaller tools. This has created stratification in the market between 3.6- and 36-volt tools, with several companies playing the middle ground at 18 volts.
Bosch plays at both ends of the voltage spectrum. You can look at the company’s 10.8-volt Pocket Driver as a miniature 12-volt drill or as a tiny cordless screwdriver — on steroids. The tool weighs 1.8 pounds and delivers 80-ft.-lbs. of torque. On the 36-volt end is the Bulldog 1-in. SDS rotary hammer. The company says that its vented batteries dissipate heat best, providing up to five times the cycle life of other brands. The tool itself is as fast as (or even faster than) the corded Bulldog. As a result of this success, the company has more Li-Ion tools in the works.
Craftsman’s 20.8-volt tools are branded with the Diehard moniker and include a 7-1/4-in. circular saw with magnesium housings, a 1/2-in. drill/driver and an adjustable work light. The batteries feature Craftsman’s SmartChip technology that optimizes the charge and protects the batteries.
DeWalt entered the market at 36 volts and aims to compete with corded tools by offering light, powerful cordless versions. The company introduced seven new tools and combo kits in what it claims is the most extensive platform of tools available in 36-volt power.
Hitachi is taking the 18-volt route into the market with tools that are lighter but offer longer run time than NiCd versions. Its HXP Li-Ion tools are also backward-compatible with some of its existing cordless tools, enabling owners of those tools to upgrade gradually as needed without sacrificing battery packs. Hitachi also offers a 3.6-volt screwdriver for light duty.
Makita hit the market hard at the 18-volt platform with tools redesigned from the bottom up. The company offers a very full line that ranges from impact drivers to concrete vibrators to circular saws. It has upgraded ergonomics, lowered the weight of the tools and even redesigned some of the motors from two-pole to four-pole. For users ready to make a switch or an upgrade, Makita’s suite is complete.
Metabo has introduced five new Li-Ion tools: an 18-volt 1-in. SDS-Plus rotary hammer, an 18-volt reciprocating saw, an 18-volt drill/driver, a 14.4-volt drill/driver and a 12-volt drill/driver along with a four-piece combo kit. The batteries and universal charger are backward-compatible with tools in Metabo’s NiCd line. The 12-volt drill/driver is one of the smallest available — and sometimes small is just what you need for woodworking or cabinetry projects. Another nice touch: The batteries have fuel-gauge lights so you know how much charge is left.
Milwaukee opened the Li-Ion floodgates in 2005 with 28-volt tools and has continued to develop its very full line with both 28- and 18-volt models. The company’s V-28 line includes high-draw tools such as a rotary hammer, a portable band saw and a circular saw. The V-18 line — which is backward-compatible with some Milwaukee NiCd tools — also includes a wide variety of 18-volt versions of the more powerful 28-volt models. The company also offers a five-year/2,000-charge warranty, which is nice guarantee of its cycle-life claims.
Ridgid’s Max Select tool system is the first line of tools that can run on two voltages and two different battery chemistries, making this one versatile system. Tool buyers can use existing 18-volt NiCd batteries in the 24-volt Max Select tools and upgrade to Li-Ion when the time is right. Ridgid is the only company that sells the tool without the battery, and its warranty offers a lifetime service agreement on parts and service, including batteries.
As manufacturers continue to introduce new Li-Ion tools, prices should fall and your choices will only get better.
Mark Clement is a carpenter, author and tool tester.