Compact Vs. Thick DeWalt 20V 4Ah Batteries: What's The Difference?

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Oddly enough, DeWalt's 20V MAX 4Ah batteries are available in both compact and thick sizes. At their core, they make the same basic promise: 20 volts of power and 4-amp-hours (Ah) of capacity. That said, their differences prove there are two distinct ways to deliver on that promise.

If you were to hold one in each hand, the first thing you'd notice is that the compact model weighs just over a pound while the thick version weighs nearly three times that. One feels small and light enough for work in tight spaces, while the other feels like it'd give you a sturdier, more durable performance given its size. But how do they compare beyond their physical appearance? Let's take a look at their measurements and their performance specs, as well as their individual warranties and price points, to really see what sets the compact and thick DeWalt 20V 4Ah batteries apart.

Despite its smaller size, measuring up to 3.5 inches wide and 7.375 inches long, the compact 20V 4Ah battery from DeWalt has a lot in common with its thick counterpart. It has the same capacity, the same LED state-of-charge indicator, and the same 3-year limited warranty, 1-year free service, and 90-day satisfaction guarantee. It's also just as compatible with the rest of the 20V MAX line, same as the thicker one.

However, the charge time for this compact version comes in at 45 minutes. That's a whole 15 minutes faster than the thick version's charge time. It's also just 1.15 pounds, which means carrying three of these compact batteries would weigh just barely more than one of the thick versions. Home Depot has it priced at $129, while Lowe's has it at $133.21.

At 3 pounds, there's no denying that the thick version of DeWalt's 20V 4Ah battery is much heavier. But it's also sturdier: Measuring 6.7 inches wide and 6 inches long, this model's denser build may just give you the increased stability you need for heavier tools. The extra pounds also come with a more rugged casing and better temperature management (meaning it can stay cooler during longer uses). Home Depot lists it at $76.65, while Lowe's has it priced the same as the compact: $133.21.

For most of us, choosing between the compact and the thick battery will depend on what we do more of. Are you looking for more lightweight handling and better agility? (Such as HVAC technicians, assembly workers, or anyone who's going to be holding the drill or driver for long periods of time?) Any one of these folks might prefer the compact version. Its smaller build fits better in tight spaces, and the reduced weight means less strain during long days. Plus, its faster charge time means you're back to 100% even quicker.

On the other hand, those who work with high-torque or otherwise very power-intensive tasks (like cutting, grinding, or demolition) may need the thicker battery. The extra thickness and added weight might make you feel like you're working with a tougher power tool overall. And the slightly longer charge time could be a perfectly reasonable tradeoff for that extra heft that heavy-duty jobs sometimes need. In either case, it's still part of DeWalt's 20V MAX system — If you have the budget, you very well could go with both and switch back and forth depending on the job.