DeWalt currently has three PowerStack (PS) batteries on the market: the 1.7 Ah (DCBP034), the 3.5 Ah (DCBP320), and the 5 Ah (DCBP520). This article will discuss whether PS batteries are worth the extra cost over regular 20V XR/MAX batteries.
Note: DeWalt has recently rebranded the PowerStack batteries with the XR logo on the side, while removing the XR logo from the side of regular XR batteries.
The main selling point of PowerStack batteries is DeWalt’s claim that they deliver 50% more power, provide 50% more work per charge, and offer twice the rechargeable lifespan of their 20V MAX equivalents.
Runtime
In our video review, the 5Ah PS and 5Ah MAX had the same runtime on a shop vac. However, after running two more vac tests we found the 5Ah MAX ran 2-4 minutes longer. So, I’d bet on the MAX battery keeping the lights on longer.
50% More Power
DeWalt claims that both the 3.5Ah and 5Ah PowerStack batteries deliver 50% more power than a 5Ah MAX battery.
As I understand it, compared to MAX batteries, PowerStacks lose less energy as heat, allowing more energy to be used for work.
In our testing (see video below), the 3.5Ah and 5Ah PowerStacks ran faster than the 5Ah MAX. It’s a clear difference you can feel. But, the 3.5 did not run cooler.
50% more work per charge
In our video review, we saw the 5Ah PS cut 78 feet of 2x lumber compared to the 5Ah MAX’s 56 feet. That’s not quite the ‘50% more work per charge’ claimed in DeWalt’s original marketing, but it’s still impressive. The 5Ah PS also ran much cooler.
The 3.5Ah PS cut 45 feet of 2x lumber, compared to the 5Ah MAX’s 53 feet. So, the 3.5 performed about 80% of the MAX’s work.
Longer Lifespan
DeWalt originally marketed the PS as having twice the lifespan of the MAX. They’ve adjusted that on their site to ‘longer lifespan,’ which could mean a couple of different things.
It could mean that, for example, if a 5Ah MAX drops to 80% of its original charge capacity after 300 recharges—which is roughly my experience—then a 5Ah PS should retain about 80% at 600 recharges.
Or maybe they mean that if the MAX recharges until it drops to, say, 60% of its original capacity before it won’t recharge anymore, the PS batteries recharge down to 30%.
All I know for sure is that full charge bars in year one don’t deliver the same runtime as full bars in year three. I also know heat is the enemy of runtime and probably reduces rechargeable lifespan.
The 1.7
The 1.7Ah PowerStack was the first PS model released, and we saw many reviews showing it outperforming DeWalt’s massive 15Ah FlexVolt battery in screw-drilling tests. In our testing, however, while the 1.7Ah was impressive, it ran slower than the 9Ah FlexVolt.
The 1.7Ah PS also ran hotter than any battery we’ve tested so far. If running cool is a key factor in DeWalt’s claim that PowerStack batteries last longer than MAX batteries, this isn’t a good sign for the 1.7Ah.
FYI: The 6 and 15Ah Flexvolt batteries use 18650 cells, whereas the 9 and 12Ah Flexvolts run 21700 cells. However, it’s not all about the cells. For example, DeWalt’s 4Ah compact battery uses 21700 cells but runs slower than the 5Ah MAX, which uses 18650 cells.
Bottom Line
For small 20V tools like wrenches, I think the 1.7Ah PowerStack is a good fit. For more power and work capacity compared to a 5Ah MAX, the 5Ah PS seems like the best bet if you can find them on sale and don’t mind the clown-shoe fit on your impact driver.
With the 3.5Ah, I ask myself: if it and the 5Ah MAX were the same price, would I trade 15% more work capacity for more power in a smaller, slightly lighter package, given the 3.5 does not run cooler than the MAX? Maybe, if they cost the same.
Let us know your thoughts in the comments and check out this review to see these bad boys in action. See ya!
