The Ultimate Guide for Dewalt Flexvolt


Dewalt Flexvolt Batteries

I have to admit, Dewalt Flexvolt confused me.

I know I shouldn’t say that, particularly in my line of work, but for complete transparency, it did. Despite all the bumf and blurb from Dewalt, I couldn’t find a simple one-line explanation of what it was. I know what it offers, I know what it is used for, but there isn’t a genuinely simple explanation as to what it is.

Is it a battery? Is it a feature on tools? Is it a system or a range?

Well, the answer is simply, yes, to all of the above.

Dewalt has developed an impressive range of incredibly powerful tools that operate 54V. These power tools not only require impressively high power batteries but also needed a new way for the batteries to control the power output to the tools.

According to Dewalt, the Flexvolt System offers the same, if not more, power than corded power tools.  

Instead of being restricted and limited in terms of movement due to cables, you can have the complete freedom of movement that Cordless power tools offer with the same power level and performance.


Dewalt Flexvolt Technology

With most Li-Ion batteries, inside there are a series of power cells, that look like ordinary AA batteries, all tied up together. When they’re used, the power is taken from all the batteries in one go. The Flexvolt battery is completely different – instead of power being drawn out in one instance, the Flexvolt technology allows the cells to be used in sequence, or series, from 1 upwards.

The result is that you will see under certain conditions, that the same charge capacity in a 6Ah Flexvolt battery might provide for more runtime than the combined 6Ah of capacity in smaller battery packs.

The benefit of all of this is, for 54V power tools, is that the demands of the user for longer runtimes are met more efficiently. The health of the battery is maintained as the battery is run in series, instead of in parallel.


Flexvolt Battery Graphic

Now, this is where things get really clever. Simply put, it allows a FlexVolt battery to be put on an 18V power tool. It is backwards compatible meaning that it will work with any 18V power tool and can even be charged in the same charger.

It unlocks up to 77% more power when needed to complete more challenging applications.

This feature delivers additional power when needed on tougher jobs and increases the versatility and runtime of your equipment.

This is why….some 18V tools will proudly list the Flexvolt Advantage.

Flexvolt Batteries will show two power capacities – one for 18V, and the other for 54V.

So if you need a power tool that delivers market-leading power but DON’T want to get rid of the collection of 18V that you already have, the Dewalt 54V Flexvolt is the ONLY to go.


Dewalt 18V vs 54V

In short, beautifully.

The Flexvolt batteries have the same connection points as a standard 18V battery. This means you can put your 54V battery on an 18V power tool. If the 18v tool has Flexvolt advantage you it will also benefit from higher power output.

However, and this isn’t bad at all, you will need to multiply the capacity by 3.

DCB546: 2.0Ah 54V (now times by 3) = 6.0Ah 18V

DCB547: 3.0Ah 54V (now times by 3) = 9.0Ah 18V

DCB548: 4.0Ah 54V > 12.0Ah 18V

DCB549: 5.0Ah 54V > 15.0Ah 18V

This means that even if you buy a 54V power tool, the battery can be used on your 18V tool as well.

The Flexvolt battery is possibly one of the more important developments from Dewalt. Not only does it display an increased flexibility across two power tool platforms, but it really does deliver the power when needed.

Yes, there are competitors in other brands, but the Dewalt Flexvolt battery along with the Flexvolt tool range outperforms these by quite a bit. I would even go so far as to say that the Flexvolt range, in all aspects epitomises and even personifies the promise that Dewalt tools are guaranteed tough.

Frequently asked questions

What is the advantage of a Flexvolt battery?

To put it simply, with a Flexvolt Battery, the amount of power available lasts longer thanks to the way the battery has been designed. Even as a side-by-side comparison, you might find that a 2.0Ah Flexvolt Battery will last longer than a standard 2.0Ah battery. This is a result of the power cells being used one at a time rather than all in one go.

What’s the difference between Flexvolt and XR?

XR has become the standard for Dewalt batteries and tools, particularly for their 12V and 18V ranges. XR simply means eXtended Running. However, for those Flexvolt batteries are aimed at those on the 54V and 18V platform delivering longer times and the power of a corded machine with the flexibility of cordless freedom.

Can I use 18V battery on Flexvolt?

18V Batteries wont work on Flexvolt tools as they require a 54V battery to operate.

Can I use Flexvolt in XR tools?

Your Flexvolt Batteries will work in 18V XR tools. They won’t work in 12V XR Tools. When using a 54V battery in an 18V tool you will tend to see 3x longer use time. 54V batteries will use an 18V array so if you have a 2Ah Flexvolt battery it will act as a 6Ah 18v battery. With Flexvolt advantage your tool will use more power than normal and give better performance too.

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