DeWALT’S New Impact Driver & Battery Tech Cause Conflicting Comparison Results!

We got conflicting results when testing Dewalt's new PowerStack Stacked Lithium battery in a comparison with dewalt old technology 20V max lithium ion cylindrical cell battery packs. While comparing PowerStack to 2AH 4AH 6AH and 8AH we used Dewalt's (DCF850P1)
ATOMIC 20V MAX 1/4 IN. BRUSHLESS CORDLESS 3-SPEED IMPACT DRIVER and as our comparison continued DeWALT’S New Impact Driver & Battery Tech (DCBP034) 20V MAX DEWALT POWERSTACK COMPACT BATTERY Caused Conflicting Comparison Results!

[gorillalover]

what do I always get the feeling that this dude wants dewalt to fail hard??

[deanolivas]

The one variable on all these tests was that you never switched the bits the tool that kept winning was using the same sharp bit. Vince in one of your previous reviews I believe it was with flex tools you stated how the accessories were more important than the tool you said it's where the rubber meets the road. If I had to guess it's all in the bit the major benefit of this battery is it size. Thanks for doing the review though much appreciated 👍

[generation-x]

As DeWalt has mentioned the powerstack has improved the contact points of the battery pouch cells "allowing more current to flow", as well as my assumption of the new battery composition allows for less internal resistance vs the round cells. In theory the less of a restriction out of the battery means more power into and out of the tool which in turn means a depleted powerstack battery faster since its able to flow more power but it will work harder till depleted. The result should be higher density battery = smaller form factor at the same capacity "not runtime". There shouldn't be any increased voltage gains between the pouch/round cells 18/20v overall. To me if you were truly getting more power out of the powerstack at 1.7ah vs to 2ah round cells the powerstacked tool should always finish first but run out of power first as well. If I had to take a guess there is some sort of "battery/tool power management tech in the battery/tool that is skewing the results, which is clearly at play when your squeezing the trigger but the tool stops running. Just my 2 cents.

[JT-lqyd]

Great testing.
It is good to see Dewalt's continued support by making this new battery type compatible with their 20 volt system, I started building my cordless Dewalt tool collection this year and seeing them doing this makes me happy.

[samiches]

Great videos, guys! Inconsistencies may be coming from the wood. Wood is a natural product and effort is affected by the grain density and direction, knots (even small ones). We've all been there. We're an inch deep drilling a hole with a spade or Forstner bit as our progress slows temporarily. We look inside the hole only to find nothing out out of the ordinary other than grain orientation. We start drilling again and break through that grain and the rest of the hole drills just fine. Does this matter in regards to this test? Probably not a whole lot. Also, a run of 10 screws instead of 1 may be more consistent.

[pc]

It's cool seeing what drills are faster and all but as someone in the construction field it comes down to durability and battery life both usage and charge time.

[rcud]

The impressive thing to me is how well it works with the old 2AH battery. For most things the DCF850 performs well with any battery.

[bobbyclarkston]

Who’s to say which gentleman is putting more force into driving THEIR screw into the wood? I highly doubt their both using the same amount on the reg, so how can they possibly compare each test to the previous one?

[realreviews]

Thanks for your videos, really helps me make my purchasing decisions. If the power stack can live up to the twice as many charges before it needs replaced deal, it’ll be the way to go.

[duncdunc]

Another great VCG tool test👍👍👍 I think when I upgrade from the 885s I will be going with the 840 since in my line of work I dont really use or need the speed modes and I do have one 887 for the finesse work. The consistency of that 850 has got me scratching my head. However, those power stack batteries on the other hand look pretty promising for us professionals that use our impacts all day long.

[biffdotorg]

Why do so many feel that Ah is a measure of the amount of power a tool will get and perform better? When in actuality, an electrical engineer and DeWalt will tell you that is more of a measure of how long the battery should last when charged.. So many act like an 8ah battery will perform better than a 2ah, when the only performance gain one should expect is longer run time.. Here is a 22 min video that proved nothing at all. Other than there are more variables than you guys expected. Although, it is a great video on what this new impact drive can do for it’s size. It is amazing! Thank you.

[runnerdude]

I have about every dewalt tool they make. I just got this impact and I’m thinking about taking it back. The trigger inconsistencies drive me nuts. When I pull the trigger I want it to spin. Every time.

[Biaanca]

I'm not unboxing my personal DCF850 until I get the powerstack. :)
I completed my "teeny tiny tool" collection by the way:
ryobi bid10XR. 10.6cm
ryobi bid11XR. 9.9cm
Dewalt DCF850. 10.08cm

All three of these can run on a powerstack because they all have XR bayonets. They take dewalt batteries :D

From what I've seen of others though: I think your problem with speed one on those 850s is that it's an automatic-stop mode for driving drywall screws, not actually a "speed 1"

[jporreca]

Really enjoyed running that power stack. All the power of 8 AH and half the size.

[raymondsloan]

I'm wondering how does the DCF850 hold up to the 887 and 888 Impacts using only the power stacks in one test. Then another test using all three impacts with the 4ah compact battery. This way a consumer could see what are the advantages of both the differences in battery power and tools?

[KnKn-rrri]

My 850 cuts out power as well. But only when i compress the trigger slightly for a moment before pulling the trigger all the way.

[MegaBuster]

The glass shattering at the drop of the plastic bag made me laugh. Props. Lol

[Nobody-urp]

I’ve been using the Powerstack batteries for about 3 weeks already and they aren’t great. I know the people are going to hate me for it and say I don’t know what I’m talking about but the Powerstack form factor and fitment is great and the power is definitely there. The run time is the issue. I know it’s only a 1.7ah but I have 1.5ah and 2.0ah 12v DeWalt and Milwaukee batteries that last longer. I have 4 Powerstack batteries and went through three, fully charged packs, using the 850 impact and the 4 1/2” circular saw. All I was doing was removing screws (it was around 60-70) from the frame of a wooden fence gate and making two cuts in 4x6 and one cut in 2x4 PT lumber. For the other odds and ends stuff, the run time is ok. But trying to use these for an extended period of time, forget it. Has anyone else experienced anything similar? Is anyone using these exclusively on the day to day.

[FangOfTruth]

The one tool does seem to be lower in power. But to me dimensional lumber has varying density even in a small area. Maybe some tests in some more densely consistent materials?Just a thought.

[dilbertgilbert]

I got that new driver. I have already snapped off three fasteners, including lag bolts. She'll get the job done, and then some.