DeWalt PowerStack 1.7Ah 20V Max Battery Review: More Power in a Smaller Pack

Introduction

Battery technology rarely gets this interesting. DeWalt’s PowerStack line abandons the traditional cylindrical cells found in almost every cordless tool pack and instead uses stacked lithium pouch cells, allowing the battery to pack more power into a smaller, lighter footprint. The debut model, the PowerStack 1.7Ah 20V Max battery, is the clearest example of what that shift makes possible.

The pitch is simple: DeWalt claims PowerStack batteries provide more power with less weight and size. That is a bold claim for a pack with slightly lower capacity than the standard 2Ah battery it goes up against, so it is worth looking closely at how it actually performs.

What Makes PowerStack Different

The core change is inside the case. Instead of rows of cylindrical lithium-ion cells, PowerStack uses stacked lithium pouch battery cells. Pouch cells can be arranged flat and stacked, which lets DeWalt reshape the pack itself. The result is a battery that is noticeably smaller and lighter than a conventional pack of similar output.

DeWalt claims the PowerStack technology provides more power and less weight and size than previous designs. That matters most when the battery is paired with compact, lightweight tools, where every gram and every bit of driving force is felt directly in the hand.

How It Performed in Testing

The PowerStack 1.7Ah was stacked up against DeWalt’s existing 2Ah 20V Max battery using a compact impact driver and a compact cordless drill. In the impact driving test, the PowerStack finished more than two seconds faster on average, a clear and repeatable advantage.

The drilling tests made the gap even more obvious. The compact 2Ah battery failed to complete most of its tests on high speed, while the PowerStack pushed through without a problem. A follow-up run at low speed answered any remaining question: the smaller pack with slightly lower capacity clearly produces more power than the 2Ah battery.

Where It Falls Short

To put the results in perspective, the PowerStack was also run against a 5Ah battery in several tests. Here the story flips: the 5Ah pack was a little bit faster. The PowerStack’s advantage is specifically over smaller and similarly sized compact packs, not over the larger high-capacity batteries in DeWalt’s lineup.

That said, the comparison itself highlights the point. A pack this small, with less capacity than a 2Ah, keeping pace anywhere near a 5Ah is impressive, and the trade-off in runtime is worth it for anyone running compact lightweight tools.

Who Should Buy It

The PowerStack 1.7Ah makes the most sense for users of compact and lightweight tools. When you are driving fasteners or drilling with a compact impact driver or drill, the extra power this pack delivers compared to smaller standard packs makes a real, noticeable difference in day-to-day work.

It is also a good fit for anyone who values a smaller, lighter battery on the tool. The reduced weight and size are felt over a full workday, particularly for overhead work or prolonged one-handed use.

Things to Consider Before Buying

The obvious trade-off is capacity. At 1.7Ah, the PowerStack holds slightly less charge than the 2Ah pack it outperforms, so runtime between charges is marginally shorter. If your priority is maximum runtime per charge, a larger pack remains the better choice.

It is also worth remembering that the power advantage narrows against DeWalt’s bigger 5Ah-class batteries, where the standard pack edges ahead in speed. Buy the PowerStack for compact tool performance and reduced weight, not as a replacement for a high-capacity pack.

Conclusion

The DeWalt PowerStack 1.7Ah 20V Max battery backs up its headline claim. In testing with a compact impact driver and compact cordless drill, it delivered more than two seconds faster driving on average, completed drilling tests the 2Ah battery could not finish on high speed, and did it all in a smaller, lighter pack. If you run compact tools, it genuinely makes a difference. If you need maximum runtime or the absolute fastest output, a larger pack still has its place.