Higher Voltage Cordless Tools: You Are Buying a Battery Platform, Not a Number
Volts do not measure power. They are one half of a multiplication. The energy in a pack is volts times amp hours, and DeWalt’s own FlexVolt page proves it: the same battery is 12Ah at 18V or 4Ah at 54V, and 216Wh either way. What changed since we last wrote this is that brushless motors made 18V enough for almost everything a UK DIYer does — and that the battery you cannot swap between brands is now the expensive part of the decision.
The short answer
Decision one: stop reading the voltage and start reading watt-hours and the word “brushless”. Voltage on its own tells you almost nothing, because the energy in a battery is volts multiplied by amp hours. DeWalt spell this out on their own XR FlexVolt page: one pack, wired as “5 cells in a series (5 x 3.6V = 18V) 3 string in parallel (3 x 4Ah = 12Ah) = 216Wh” or as “15 cells in a series (15 x 3.6V = 54V) 1 string in parallel (1 x 4Ah = 4Ah) = 216Wh”. Identical cells, identical energy, three times the voltage. If voltage were power that battery would be a miracle; it is arithmetic. What decides whether a drill drives a 100 mm screw into a joist is the motor, and Makita claim their brushless motors are “up to 50% more efficient than a comparative model”, a charged 18V pack lasting “almost twice as long as a product running on a standard motor”. A brushless 18V drill out-works a brushed one of any voltage — the single biggest change since we last published this page in 2021.
Decision two — the one that costs real money — is which battery platform you marry. Nothing fits anything else. Makita’s own 18V LXT and 40V max XGT packs do not fit each other’s tools, and on the day we checked, a Makita LXT 5.0Ah pack was £69.99 at Screwfix while an XGT 2.5Ah pack was £129.99 — both holding 90 watt-hours by our own arithmetic. Nearly twice the price for the same stored energy, because you are paying for the newer platform, not for more of anything. Spread across the three or four tools most people end up owning, the packs cost more than the tools do. Choose the system you can afford to feed.
What we would actually buy for a UK house. An 18V brushless combi drill with two batteries, from whichever big system you are likely to keep buying into. The DeWalt DCD778D2 at £99.99 (4.9/5 from 425 reviews at Screwfix, 8 September 2026) is the honest benchmark: brushless, 65 Nm, two 2.0Ah packs, 1.6 kg. Two small packs beat one big one, because the drill that works is the one with a charged battery on it. A 12V kit is genuinely better if your work is flat-pack, sockets and shelves — 1.2 kg with the battery on, and 30 Nm drives every screw a flat-pack contains. A 36V or 40V max drill is a professional purchase being sold to you as an upgrade.
And one piece of plain marketing to see through: “20V MAX” is 18V. Pro Tool Reviews quote the asterisk from DeWalt’s own website — “20 volts initial maximum measured without load, 18 volts nominal”. Five lithium cells are 3.6V each nominal and just over 4V each fresh off the charger. The same trick turns 10.8V into “12V max” and 36V into “40V max”. It is not a lie, but it is not a different battery either.
Six cordless drills across 12V, 18V and 40V max, on the retailer's own listing
| Drill | Price | Motor | Max torque | Weight | Buyer rating |
|---|---|---|---|---|---|
| Makita HP333DZ 12V CXT combi, bare Screwfix | £41.98 no battery or charger | Brushed | 30 Nm | 0.9 kg (without battery) | 4.8/5 from 4 |
| DEWALT DCD778D2-SFGB 18V XR combi, 2 x 2.0Ah Screwfix | £99.99 | Brushless | 65 Nm | 1.6 kg (with battery) | 4.9/5 from 425 |
| Makita DHP484Z 18V LXT combi, bare Screwfix | £107.99 no battery or charger | Brushless | 54 Nm (Makita UK: 54/30 Nm hard/soft) | 1.2 kg (without battery) | 4.7/5 from 23 |
| Erbauer ERI1107COM 18V EXT combi, 2 x 5.0Ah Screwfix | £159.99 | Brushless | 150 Nm | 5.25 kg as listed — that is the boxed kit, not the drill | 4.9/5 from 8 |
| Milwaukee M12 BDDX-202C 12V drill driver, 2 x 2.0Ah Screwfix | £174.99 | Brushed | 32 Nm | 1.2 kg (with battery) | 4.9/5 from 17 |
| Makita HP003GZ01 40V max XGT combi, bare Screwfix | £214.99 no battery or charger | Brushless | 180 Nm | Not published on the listing | None — not yet rated |
Every price, rating and sample size read off Screwfix’s own product pages on 8 September 2026; the DHP484 torque split is from Makita UK’s own spec page. Two figures we are not going to launder: Screwfix give the Erbauer’s weight as 5.25 kg, which is plainly the kit in its case rather than the tool, and they list the Milwaukee M12 as 12V where Makita call the same cell count “12V max”. Also on the shelf: the DEWALT DCD996X1-GB 18V/54V FlexVolt combi at £289.99, not yet rated. Professional Electrician (16 March 2026) reported the HP003G’s 180 Nm as the most powerful combi drill in Makita’s range.
What the 2021 version of this page got wrong
The original post is no longer on the site at all — the URL returns a 404 and the Wayback Machine copy would not open for us — so we cannot quote our own old wording back line by line, and we are not going to pretend we can. What we can tell you is what the 2021-era answer looked like, and why it is now wrong.
It treated volts as a power rating
The old framing was a ladder: 12V for light jobs, 18V for real jobs, 36V for serious jobs. That was a reasonable shorthand when motors were brushed and packs were 1.5–3.0Ah. It stopped being true when brushless motors and bigger cells arrived, because a brushless 18V tool with a 5.0Ah pack now does work that used to need a 36V brushed one. The number on the badge did not change; what it buys did.
It ignored platform lock-in, because in 2021 there was less of it
Makita’s XGT is the clearest example: a separate 40V max platform with no battery compatibility with the 18V LXT tools Makita has sold for years. ToolGuyd, reporting the launch, put it bluntly — “ZERO compatibility between Makita XGT and 18V tools and batteries”, only a one-way charging adapter, and Makita declined to say why. A DIYer with a shed full of LXT who buys an XGT drill has started a second collection.
It did not put a price on a spare battery
The number that decides the purchase, and nobody printed it. Our costs table below does: a spare 5.0Ah 18V pack runs £44.99 to £69.99 depending on the badge, and a 2.5Ah XGT pack is £129.99.
What voltage actually tells you (and what it does not)
Voltage is electrical pressure, and higher-voltage platforms exist for a real reason on genuinely heavy tools — breakers, mitre saws, chainsaws. But on a hand tool it is one term in a multiplication, and the marketing leans hard on the term it can print largest.
Nominal versus maximum: the “20V MAX” question
A lithium cell sits at about 3.6V nominal and just over 4V when it comes off the charger with nothing drawing from it. Five in series is 18V nominal and 20V for the moment before you pull the trigger. Pro Tool Reviews quote DeWalt’s own asterisk verbatim: “20 volts initial maximum measured without load, 18 volts nominal”, and ToolGuyd’s account matches — “There is no functional difference between 20V Max and 18V”, the naming adopted at the June 2011 launch to separate the new lithium tools from DeWalt’s legacy 18V nickel-cadmium range. In Britain you mostly meet the same tools badged 18V XR. It matters when you buy from a US-facing marketplace and think you have found something more powerful. You have found the same battery.
The same trick, one rung down and one rung up
“12V max” tools are three cells: 10.8V nominal, 12V off the charger. “40V max” is ten cells: 36V nominal, 40V off the charger. Makita badge CXT and XGT with the max figure; older listings for the same tools say 10.8V and 36V. Two names, one battery. Said plainly: we have DeWalt’s statement in writing for the 18V/20V case and have extended the same cell arithmetic to the other two ourselves. We did not find the equivalent footnote from Makita.
The two specs that replaced voltage: watt-hours and brushless
Watt-hours: how much work is in the pack
Multiply the nominal volts by the amp hours. An 18V 5.0Ah pack is 90 watt-hours; a 36V (“40V max”) 2.5Ah pack is also 90 watt-hours; a 12V 4.0Ah pack is about 48. That is our arithmetic rather than anyone’s data sheet, and it is the only way to compare a Makita pack with a DeWalt one. It is also the fastest way to spot when you are being sold air: the XGT 2.5Ah pack at £129.99 and the LXT 5.0Ah pack at £69.99 hold the same 90 watt-hours.
DeWalt make the point better than we can. Their FlexVolt battery physically rewires itself, and their own page gives both configurations of one pack: 18V at 12Ah, or 54V at 4Ah, and 216Wh either way. If you take one thing from this page, take that line.
Brushless: where the power actually went
A brushed motor drags carbon blocks against a spinning commutator. That friction is heat, the heat is wasted battery, and the brushes wear out. A brushless motor switches electronically instead. Makita’s own claim for their BL motors is “up to 50% more efficient than a comparative model”, a charged 18V pack lasting “almost twice as long as a product running on a standard motor”, and lower housing temperatures under hard use. That is a maker marketing its own technology, so treat “up to” as the weasel it is — but the whole trade moved this way, which tells you something.
Practically: given two drills at the same price, take the brushless one at the lower voltage over the brushed one at the higher voltage. In our table, the £99.99 brushless 18V DeWalt makes 65 Nm; the £174.99 brushed 12V Milwaukee makes 32 Nm. The gap is not the volts.
The platform is the purchase: what each UK system locks you into
Every one of these packs is a different shape with a different latch. Nothing crosses. Here is what you are signing up to.
Makita: LXT 18V and XGT 40V max, and they do not mix
LXT is the huge, mature, everywhere-in-Britain system; XGT is the newer high-power one. They are separate platforms with no battery interchange — the adapters in Screwfix’s 40V listing are charging adapters, not a way of running an LXT tool from an XGT pack. If you already own LXT, adding XGT is starting again. Makita have said they will keep launching LXT tools, which ToolGuyd report they “strongly emphasise”.
DeWalt: 18V XR, and FlexVolt as the bridge
The most DIY-friendly answer to the voltage problem. FlexVolt packs switch themselves between 54V and 18V and DeWalt state they are “backwards compatible with the entire XR 18V range, so any tool or charger you have can be powered by XR FLEXVOLT batteries”. Buy 18V XR now, and if you ever need a 54V mitre saw you do not restart your collection. Note the asymmetry: a plain 18V pack will not run a 54V tool.
Bosch: 18V Professional (blue), 12V, and AMPShare
Screwfix’s listing for the GBA 18V 5.0Ah says it fits all tools and chargers in the Bosch Professional 18V System and the AMPShare Alliance — a cross-brand arrangement, and the one thing here pushing against lock-in. Bosch also run a separate green DIY line; blue and green are not the same system, and that is the commonest Bosch mistake.
Ryobi ONE+ and Einhell Power X-Change: breadth, cheaply
Ryobi ONE+ is sold in Britain mainly through B&Q and the pitch is breadth — one 18V pack across drills, garden kit, cleaners, lights. Einhell claim “over 300 tools and appliances” on one battery, and a press release dated 8 September 2025 says they took a Guinness World Record running more than 300 of them from a single pack without a recharge. A stunt, but the catalogue behind it is real, and an Einhell battery-and-charger starter kit is £39.98 at Screwfix. If your ambitions include a strimmer and a pressure washer, these two cost least to extend.
Milwaukee M12 and M18, and Erbauer EXT
M12 is the best small system on the market and M18 the heavy one; they do not share packs, and both are priced for people whose tools earn money. Erbauer EXT is the opposite end: the cheapest route into a coherent 18V platform in Britain, with a 5.0Ah pack at £44.99, 4.9/5 from 34 reviews, a third less than the Makita equivalent. The catch is that it is a retailer’s own brand at one chain, with a one-year guarantee on the battery where Makita and Milwaukee list two.
Twin 18V, and the halfway houses
Two 18V packs, wired in series by the tool
Makita call it 18Vx2 LXT: the tool takes two of the 18V batteries you already own and runs at 36V. Screwfix’s listing for the DLM382Z 36V mower (£234.99, 3.8/5 from 17 reviews) says it plainly — “Runs on 2 x 18V lithium batteries from Makitas LXT battery platform”. For a DIYer this is usually the right way to buy 36V: the higher-voltage tool without a second charger, a second pack shape or a second set of spares. The trade-off is that it eats both your batteries at once.
One pack, two voltages
DeWalt’s FlexVolt does the same job from the other end — the battery rewires itself rather than the tool combining two. Both exist because the makers know that asking people to fund a second battery platform is the thing most likely to lose the sale.
Where genuinely higher voltage does earn its money
Not drills. It is sustained, high-draw work: cordless mitre saws, table saws, breakers, chainsaws, big mowers. Makita’s 180 Nm XGT combi is a real tool for people fixing structural timber all day. If your hardest job of the year is a 6 mm hole in a brick wall for a hanging basket, an 18V brushless combi will not notice.
And if you already own a platform
Stay on it unless the tool you need genuinely does not exist there. A bare unit on a system you already feed beats a complete kit on a new one, nearly every time — that is the whole argument on this page in one sentence. If someone is selling you 40V max for a house, ask what it is for; if the honest answer is “drilling and screwing”, you are paying a £60 premium on every battery for headroom you will never use.
What a spare battery costs on each platform
| What | Figure | What it means |
|---|---|---|
| Erbauer EXT 18V 5.0Ah | £44.99 ≈ 90Wh · £0.50/Wh | ERI1100BAT at Screwfix, 4.9/5 from 34 reviews. Fits “all Erbauer 18V EXT products”. One-year guarantee, and a Screwfix-only platform. |
| Bosch Professional 18V 5.0Ah | £49.99 ≈ 90Wh · £0.56/Wh | GBA CoolPack at Screwfix, 5/5 from 16 reviews. Listed as fitting the Bosch Professional 18V System and the AMPShare Alliance. One-year guarantee. |
| DeWalt 18V XR 5.0Ah | £54.99 ≈ 90Wh · £0.61/Wh | DCB184-XJ at Screwfix, 4.9/5 from 276 reviews — the biggest sample of any battery we checked bar the Milwaukee. One-year guarantee. |
| Milwaukee M18 5.0Ah | £59.99 ≈ 90Wh · £0.67/Wh | M18 B5 at Screwfix, 4.9/5 from 185 reviews. Two-year guarantee on registration; rated to work at −20°C. |
| Makita LXT 18V 5.0Ah | £69.99 ≈ 90Wh · £0.78/Wh | BL1850B at Screwfix. Two-year guarantee, 0.6 kg, 45-minute charge. Ratings disagree: 4.9/5 from 11 reviews on the product page, from 8 on the category listing, same day. |
| Makita XGT 40V max 2.5Ah | £129.99 ≈ 90Wh · £1.44/Wh | 191B36-3 at Screwfix, not yet rated. Same 90 watt-hours as the £69.99 LXT pack by our arithmetic, at 1.9 times the price — and it will not fit an LXT tool. |
| DeWalt FlexVolt 18V/54V 6.0Ah | £94.99 watt-hours disputed | DCB546-XJ at Screwfix, 4.9/5 from 29 reviews. We could not settle its energy. Screwfix and DeWalt’s own spec table both say 6.0Ah at 54V, which is 324Wh; DeWalt’s FlexVolt page works its example at 3:1 (4Ah at 54V = 12Ah at 18V), which makes this 108Wh. Both are DeWalt’s. We are not picking. |
| Ryobi ONE+ 18V, 4.0Ah plus 2.0Ah | £99.99 ≈ 108Wh the pair · £0.93/Wh | Toolstation, no reviews on the listing. Two packs, not one. B&Q is the main UK Ryobi seller but their pages would not render figures for us, so this is Toolstation’s price. |
| Einhell Power X-Change 18V 4.0Ah plus charger | £39.98 battery ≈ 72Wh | Starter kit at Screwfix, 4.9/5 from 14 reviews, one-year guarantee, 75-minute charger. Not comparable per watt-hour with the bare packs above — you are getting the charger too. |
| Milwaukee M12 4.0Ah | £39.95 ≈ 48Wh · £0.83/Wh | M12 B4 at Screwfix, 4.5/5 from 8 reviews. Cheapest pack here in pounds, second dearest per watt-hour. That is the real cost of a 12V platform: small packs run out sooner and you buy more of them. |
Before you buy, check
- Is it brushless? If the listing does not say so, assume brushed. That one word matters more than any voltage figure on the box.
- Work out the watt-hours yourself. Volts times amp hours. It is the only number that compares a Makita pack to a DeWalt one, and no UK retailer prints it.
- What does a spare battery cost on this platform? Look it up before you buy the tool. Ours run from £39.95 to £129.99 for a single pack.
- Kit or bare unit? A bare drill is £40–70 cheaper — but only a saving if you already own charged batteries of the right shape.
- Two small packs or one big one? Two, for almost everyone.
- One-year guarantee or two? Erbauer and Bosch listed one year on their batteries; Makita and Milwaukee listed two. On the part that wears out, that matters.
- Are you being sold “20V MAX”? It is 18V, on DeWalt’s own asterisk. Do not pay a premium for the bigger number.
- If you want 36V, can you get it as twin 18V? Makita’s 18Vx2 tools run on two LXT packs you already own, which keeps you on one platform.
- Check the weight with the battery fitted. Listings mix bare and kit weights freely — one of ours said 5.25 kg, which is the case, not the drill.
Where this came from
- DEWALT UK — XR FlexVolt system page The 18V/54V switching and backwards-compatibility claims, and the worked example: 12Ah at 18V or 4Ah at 54V, 216Wh either way · checked 8 September 2026
- Pro Tool Reviews — 20V Max vs 18V DeWalt’s own footnote quoted verbatim, and the cell arithmetic · checked 8 September 2026
- ToolGuyd — DeWalt 20V Max vs 18V No functional difference between the two, and the June 2011 launch context for the naming · checked 8 September 2026
- ToolGuyd — Makita LXT and XGT are not compatible Zero LXT/XGT battery compatibility, the one-way charging adapter, and Makita’s commitment to LXT · dated 1 April 2021, checked 8 September 2026
- Makita UK — brushless motors Up to 50% more efficient, almost twice the run time, lower housing temperature · checked 8 September 2026
- Makita UK — DHP484 specification The 54/30 Nm hard/soft torque split and 0–500/2000 rpm · checked 8 September 2026
- Screwfix — DEWALT DCD778D2-SFGB £99.99, 4.9/5 from 425 reviews, 65 Nm, 1.6 kg, brushless · checked 8 September 2026
- Screwfix — Makita DHP484Z bare unit £107.99, 4.7/5 from 23 reviews, 54 Nm, 1.2 kg · checked 8 September 2026
- Screwfix — Makita HP333DZ 12V CXT bare unit £41.98, 4.8/5 from 4 reviews, 30 Nm, 0.9 kg, brushed · checked 8 September 2026
- Screwfix — Milwaukee M12 BDDX-202C £174.99, 4.9/5 from 17 reviews, 32 Nm, 1.2 kg, brushed · checked 8 September 2026
- Screwfix — Erbauer ERI1107COM 18V EXT combi £159.99, 4.9/5 from 8 reviews, 150 Nm, the listed 5.25 kg, one-year guarantee · checked 8 September 2026
- Screwfix — Makita combi drill listing The 40V max XGT HP003GZ01 at £214.99, 180 Nm, no rating yet · checked 8 September 2026
- Screwfix — DEWALT combi drill listing The DCD996X1-GB FlexVolt combi at £289.99 unrated; DCD778M2T £139.99, 4.8/5 from 785 · checked 8 September 2026
- Screwfix — Makita 40V XGT battery listing The 191B36-3 2.5Ah XGT pack at £129.99, no reviews; refurbished £103.99 · checked 8 September 2026
- Screwfix — Makita BL1850B 18V 5.0Ah £69.99; 4.9/5 from 11 reviews here against 8 on the listing; two-year guarantee · checked 8 September 2026
- Screwfix — DEWALT DCB184-XJ 18V 5.0Ah £54.99, 4.9/5 from 276 reviews, one-year guarantee · checked 8 September 2026
- Screwfix — DEWALT DCB546-XJ FlexVolt battery £94.99, 4.9/5 from 29 reviews, and the 6.0Ah-at-54V labelling · checked 8 September 2026
- DEWALT — DCB546 product specification The maker’s spec table: capacity 6 Ah, voltage 54 V, no 18V-mode figure, no watt-hours · checked 8 September 2026
- Screwfix — Erbauer ERI1100BAT 18V 5.0Ah £44.99, 4.9/5 from 34 reviews, one-year guarantee · checked 8 September 2026
- Screwfix — Bosch GBA 18V 5.0Ah £49.99, 5/5 from 16 reviews, and the AMPShare Alliance claim · checked 8 September 2026
- Screwfix — Milwaukee M18 B5 battery £59.99, 4.9/5 from 185 reviews, two-year guarantee on registration · checked 8 September 2026
- Screwfix — Milwaukee M12 B4 battery £39.95, 4.5/5 from 8 reviews — the 12V line in our costs table · checked 8 September 2026
- Screwfix — Einhell Power X-Change starter kit Battery and 75-minute charger, £39.98, 4.9/5 from 14 reviews · checked 8 September 2026
- Einhell — press release on the 300-tool record One battery running over 300 tools, and the Guinness record behind it · released 8 September 2025
- Toolstation — Ryobi 18V ONE+ battery pair A 4.0Ah and 2.0Ah pair at £99.99, no reviews on the listing · checked 8 September 2026
- Screwfix — Makita DLM382Z twin-18V mower £234.99, 3.8/5 from 17 reviews, and the twin-18V wording · checked 8 September 2026
- Professional Electrician — Makita 40V max combi The HP003G’s 180 Nm, and the most-powerful-in-range claim · published 16 March 2026
What we could not check
- We could not read our own old page. The 2021 original 404s at its own URL and the Wayback copy would not open for us, so the section on what it got wrong describes the 2021-era consensus rather than quoting our own sentences back.
- Every watt-hour figure here is our own arithmetic, not a published specification — nominal volts times stated amp hours. Nobody prints watt-hours on a UK retail listing.
- The FlexVolt DCB546’s energy is unresolved. Screwfix and DeWalt’s own spec table say 6.0Ah at 54V; DeWalt’s FlexVolt page works its example at 3:1. That is 324Wh against 108Wh. We have quoted both and picked neither.
- No manufacturer footnote for “12V max” or “40V max”. The nominal-versus-maximum point is documented for DeWalt’s 18V/20V case; we extended the cell arithmetic to 10.8V and 36V ourselves.
- No independent testing of any of these drills. Every torque, weight and speed is the maker’s or the retailer’s own, and torque is not measured to a common standard between brands — 65 Nm from one and 54 Nm from another are not comparable.
- The brushless efficiency claims are Makita’s own marketing, and we found no independent test of “up to 50%”.
- Two of the six drills have thin or no review samples — the XGT has none and the 12V Makita has four. A 4.8 from four buyers is not evidence of anything.
- B&Q’s pages would not give us prices or ratings, so Ryobi ONE+ is priced from Toolstation, and one retailer listed the Ryobi drill we looked at as delisted. Ryobi is the weakest set of figures on this page.
- We have not verified the AMPShare cross-brand claim beyond Screwfix repeating it on a Bosch listing, nor checked who is in that alliance today.
- Prices are from 8 September 2026 at Screwfix and Toolstation, both trading and fetched live on the day. Several were promotional and they will have moved.
Prices and specifications change constantly. Every figure here is dated — check the one in front of you before spending.