What To Know About DeWalt Interchangeable Batteries (There's A Small Catch)

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DeWalt has an enviable reputation for the quality and durability of the cordless equipment they offer and regularly come out on top when you check on the best power tools ranked. One of the keys to their success is producing batteries in different formats to serve a variety of users. In addition to the usual 20V models, there are high-performance 60V options for some tools.

While voltage defines the amount of power a battery delivers, there is also a choice of Amp hour (Ah) capacity across DeWalt's batteries. This is important because Ah is a bit like fuel: if you have two batteries of the same voltage, the one with higher Ah will run longer before it needs to be charged. DeWalt batteries range from 2Ah as supplied with the DeWalt 20V Max Drill/Driver Kit, which is hugely popular with DIYers, to the 12Ah Flexvolt designed for heavy-duty professional applications.

Whether you bought one of the cordless DeWalt tools under $100 or you've paid several times that for contractor-grade equipment, it's likely you'll need at least one spare battery. They aren't cheap, so you'll want to maximize your investment by grabbing a battery that works on as many different DeWalt tools as possible. Normally, interchangeability is excellent, but there is a small catch: some older tools may not work with the most recent batteries, and because of DeWalt's near legendary reliability, there's likely to be plenty of those tools still around. Let's look at the issue in more detail.

Let's start with 12V tools. DeWalt introduced the 12V Max system in 2010. From that date, all 12V batteries are interchangeable with all 12V tools, including the latest Xtreme range. It may be obvious, but just to be clear, you cannot use 12V batteries in 20V tools or vice versa.

DeWalt 20V battery names can be confusing. To simplify: 20V Max, 20V Max Powerstack, and 20V Max XR all have slightly different technologies inside (and you may want to check out what XR stands for), but they are all interchangeable with any DeWalt 20V Max tool. DeWalt also has the clever Flexvolt system with batteries that are clearly marked 20V/60V. Although designed for high-performance 60V tools, these batteries will automatically drop down to 20V if plugged into a 20V Max model, thus giving outstanding versatility. DeWalt's 60V Max and 120V Max tools require either one or two Flexvolt batteries. There is no way to combine the 20V Max batteries to power these models.

The 20V Max range has been around since 2011. Before that, DeWalt used an 18V system, and unfortunately none of DeWalt's current batteries are interchangeable. However, there are a number of very affordable 18V to 20V adapters available, and while they do add a little bulk, they will allow you to use current DeWalt battery technology in older tools that are still going strong today.