Log Woodworking Tools

Maxwell: Battery test on cordless tools yields surprising results

Cordless power tools succeed or fail on their batteries, and right now battery technology has improved to the point where there’s virtually no need to use plug-in tools for most home improvement jobs.

Entire houses can even be built without being tethered to an outlet or generator, but only if you choose the right equipment. That’s the challenge. These days there’s such a wide performance difference between visually similar cordless tools, it’s easy to buy new equipment that’s substantially inferior to leading-edge technology. You have to be careful.

Even tools that have the same voltage rating can perform very differently in the real world. That’s why I tested the loudest and most blatant cordless tool performance claim out there right now. It has to do with one particular kind of battery, and what I discovered during my tests indicate that improvements in battery technology continue to happen and accelerate.

The Claim

Milwaukee is one of a handful of international power tool manufacturers and they claim to have developed a proprietary battery technology that beats everything else on the market in a big way. Figures like 40 per cent longer run time between charges and 20 per cent more power than the best competing batteries are being quoted — and this sounds like typical advertising hype to me because those gains are so huge. That’s why I put these numbers to a very rigorous, real-world test.

The Test

Milwaukee’s RedLithium batteries are the source of all the talk, and to test them I used an 18-volt impact wrench to drive ½-inch diameter by 6-inch long lag bolts into and out of predrilled holes in the side of a red oak test log as many times as possible on a full charge. I used the identical tool to test two batteries — one was Milwaukee’s regular 18-volt and the other a RedLithium 18-volt.

To make the test as accurate as possible, I ran each lag bolt in and out of a 3/8-inch diameter pilot hole only 10 times, before moving onto a new hole. More drives than this and the holes got too large to maintain consistent friction. Fresh holes mean tough driving, and that’s what I wanted. To measure claims for increased power, I also timed how long it took to drive each batch of test bolts from start to dead battery.

One of the unexpected surprises of the test was just how hot the lag bolts became. After 15 or 20 drives into and out of the wood, the entire lag bolt was way too hot to touch. The oak log I used was still fresh enough to contain lots of sap, which boiled away vigorously around each bolt as it went into and out of the steaming wood. When the bolts got really hot, it even caused audible puffs of steam to come out of the hole as the metal pulled away from the wood.

The Rockwell 3RILL™ & Transformer™ at the Woodcraft Vendor Trade Show

, A cordless drill that does it all AND it comes with a LIFETIME REPLACEMENT BATTERY program. The 3RILL™ is an impact driver, two-speed drill, and screwdriver—three awesome tools in one! Never before has a tool of this size been able to cover such a wide range of drilling and driving applications. In impact mode, the 3RILL™ pounds out 800 inch pounds of torque driving force. When used as a drill, the driving speed tops out at 2,200 RPM. The 1/4″ quick-change hex chuck makes changing from drilling to driving bits a snap. In screwdriver mode, the clutch can be set as low as 3 inch pounds of torque. This means the 3RILL™ can drive even the smallest, most delicate brass screws without damage, and then instantly change and drive a huge lag bolt without a problem. , is both a time-saver and a money-saver. The three-in-one cordless tool functions as a drill, screwdriver and impact driver, plus it comes with a lifetime replacement battery program.

The 12-volt 3RILL™ weighs only 2.7 pounds but delivers 800 inch pounds of torque driving force in impact mode, a top driving speed of 2,200 RPM in the two-speed drill mode, and a minimum 3 inch pounds of torque in the screwdriver mode (22 clutch settings). A quick-change hex chuck makes switching from drilling to driving a snap. Whether you need to drill holes in wood and metal, drive small screws with controlled torque, or fasten bolts or screws with high speed, the 3RILL™ can do it quickly. The 12-volt lithium-ion battery charges 100% in 30 minutes, virtually eliminating downtime.

For Andrew Bondi, Woodcraft power tool sales manager, the battery program is a major selling point for the 3RILL™. “With the high price of replacement batteries, the Rockwell lifetime replacement battery program eliminates any added expense of spending money for replacement batteries after a few years of use. That means more money in the customer’s pocket.”  The 3RILL™ weighs less than three pounds and is well balanced, allowing the user to perform all applications comfortably. This TORQUE ON DEMAND Li-Ion 12 volt all-in-one drill and drive machine will lead the pack with its efficient design and performance. Charging time is only 15 minutes for a 75% charge and 30 minutes for a 100% charge, so downtime is virtually eliminated. Includes: 3RILL™, two 12V Li-Ion Batteries, Charger, Carry Case, Assorted selection of drills and driver bits and LIFETIME REPLACEMENT BATTERY program.