DeWalt XR vs FlexVolt vs POWERSTACK UK: Which Battery Should You Buy?
DeWalt sells three kinds of battery for its 18V range in the UK: standard XR, FlexVolt and POWERSTACK. They all slide onto 18V XR tools, but they are built differently and only one of them runs DeWalt’s 54V tools. Here is how DeWalt XR vs FlexVolt vs POWERSTACK compares, and which one to buy.
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Buy POWERSTACK for drills, drivers and most everyday 18V tools, as DeWalt says its 5Ah pack gives more power and longer life than the standard 5Ah XR battery. Buy FlexVolt if you own or plan to buy 54V tools such as big saws and grinders, or want the longest runtime on high-draw 18V tools. Buy standard XR batteries if you want the cheapest way to add capacity.
XR vs FlexVolt vs POWERSTACK at a Glance
| Feature | XR (e.g. DCB184 5Ah) | FlexVolt (e.g. DCB547 9Ah) | POWERSTACK (e.g. DCBP518 5Ah) |
|---|---|---|---|
| Voltage | 18V | 18V or 54V, switches automatically | 18V |
| Cell type | Cylindrical cells | Cylindrical cells | Stacked pouch cells |
| Fits 18V XR tools | Yes | Yes (runs at 18V) | Yes |
| Fits 54V FlexVolt tools | No | Yes | No |
| Example capacity | 5.0Ah | 9.0Ah at 18V / 3.0Ah at 54V | 5.0Ah |
| DeWalt’s claim vs DCB184 | Baseline | Not stated | 50% more power, up to 2x runtime in demanding jobs, 2x lifetime |
| Size and weight | Standard | Largest and heaviest | Compact; DeWalt lists 0.747 kg for the 5Ah |
The Key Differences
What fits what
All three slide onto DeWalt 18V XR tools. A FlexVolt battery runs at 18V in an XR tool and switches to 54V in a FlexVolt tool. DeWalt’s 54V FlexVolt tools only take FlexVolt batteries, so standard XR and POWERSTACK packs will not run them. If you have any 54V tools, you need at least some FlexVolt batteries.
POWERSTACK
POWERSTACK batteries use stacked pouch cells rather than the cylindrical cells in XR and FlexVolt packs. DeWalt says the 5Ah POWERSTACK delivers 50% more power than its DCB184 5Ah XR battery, up to twice the runtime in demanding applications and twice the lifetime in charge cycles, based on its own tests. DeWalt lists the 5Ah POWERSTACK at 0.747 kg.
FlexVolt
FlexVolt batteries are the biggest and heaviest of the three, but they hold the most energy. The DCB547 is rated 9.0Ah at 18V or 3.0Ah at 54V. On high-draw 18V tools such as circular saws, grinders and SDS drills, a FlexVolt pack gives long runtime, but it makes a small drill or impact driver heavy and badly balanced.
Standard XR
Standard XR batteries such as the DCB184 5Ah are usually the cheapest per amp hour, and are widely available in twin packs and kits. They are a sensible way to add spare capacity if you already own DeWalt 18V tools and do not need the extra power of POWERSTACK.
The Three Batteries
1. DeWalt DCBP518H2 POWERSTACK 5Ah (twin pack)
Best for most 18V toolsTwo 18V 5Ah POWERSTACK batteries with stacked pouch cells. DeWalt claims 50% more power and twice the lifetime of its DCB184 5Ah XR battery, in its own tests. Fits all 18V XR tools.
2. DeWalt DCB547 FlexVolt 9Ah
Best for 54V tools and high-draw 18V tools18V/54V FlexVolt battery, rated 9.0Ah at 18V or 3.0Ah at 54V. Runs DeWalt 54V FlexVolt tools and works in 18V XR tools.
3. DeWalt DCB184 XR 5Ah
Best budget spare batteryStandard 18V XR 5Ah lithium-ion battery with a fuel gauge. Fits all 18V XR tools, and usually the cheapest way to add capacity.
Which Should You Buy?
- Electricians, plumbers and second-fix trades with drills and drivers: POWERSTACK.
- Carpenters, groundworkers and builders with 54V saws or grinders: FlexVolt, at least one or two packs.
- Want cheap spare capacity: standard XR.
- Choosing a drill to go with them: see our DeWalt DCD796 vs DCD805 comparison.
- Still choosing a brand: see our DeWalt vs Makita vs Milwaukee guide.
Frequently Asked Questions
Can I use a FlexVolt battery in an 18V XR tool?
Yes. FlexVolt batteries switch to 18V in DeWalt 18V XR tools. They are heavier than standard XR or POWERSTACK packs, so they suit high-draw tools better than small drills.
Can I use POWERSTACK batteries in FlexVolt 54V tools?
No. DeWalt 54V FlexVolt tools only run on FlexVolt batteries. POWERSTACK and standard XR batteries are 18V only.
Is POWERSTACK better than XR?
DeWalt says its 5Ah POWERSTACK delivers 50% more power, up to twice the runtime in demanding applications and twice the lifetime of its DCB184 5Ah XR battery, in its own tests. POWERSTACK packs usually cost more.
Will DeWalt XR batteries fit my older DeWalt 18V tools?
XR, FlexVolt and POWERSTACK are slide batteries for DeWalt’s 18V XR range. Older DeWalt 18V tools with stem-style batteries need a different battery or an adapter, so check the battery type on your tool first.
Related Guides
- All Tool Comparisons UK
- DeWalt DCD796 vs DCD805 UK
- DeWalt DCF887 vs DCF809 UK
- DeWalt vs Makita vs Milwaukee UK
- Milwaukee M12 vs M18 UK
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