A new cordless platform launch is a rare event, and it changes the math for every tool buyer who pays attention. When a major brand announces a 40V Max system, the announcement carries more than a new logo: it signals new battery packs, new chargers, new tool designs, and a new answer to the question of which platform will still be supported in a decade. The launch also shows what happens to a cordless tool system when power tool platforms change battery design: packs get bigger or smaller, voltages shift, and compatibility questions replace shopping questions.
What a New Voltage Class Actually Changes
The headline number is 40V Max, a deliberate step above the 36V rating the same brand has used for years. The jump exists to separate the new tools and batteries from the older platform in the market, not because the motors demand exactly 40 volts. In practice, Max voltage is a measurement taken at full charge, and the working voltage under load is lower. What matters for the buyer is what the packs are built from and what they weigh.
The new system starts with two battery sizes: a 2.5Ah pack and a 4.0Ah pack. The smaller one is built from ten lithium-ion cells, which means it should not be physically larger than a ten-cell 18V pack of the same cell type. Cell size drives the difference between the two packs. The 2.5Ah pack appears to use 18650-sized cells, the long-standing standard, while the 4.0Ah pack likely uses 21700-sized cells, which are fatter and hold more capacity per cell. That distinction matters because 21700 cells usually start around 3.0Ah each; a 2.5Ah pack built on 21700 cells would be unusual.
| Battery | Nominal capacity | Cell count | Likely cell size | Energy stored |
|---|---|---|---|---|
| New 40V pack, small | 2.5Ah | 10 | 18650 | about 100 Wh |
| New 40V pack, large | 4.0Ah | more, larger cells | 21700 | about 160 Wh |
| Typical 18V pack | 5.0Ah | 10 to 15 | 18650 or 21700 | about 90 Wh |
The energy math is straightforward: 40 volts times 2.5 amp-hours is about 100 watt-hours, 40 times 4.0 is about 160, and a typical 18V 5.0Ah pack stores about 90. The new packs carry more energy per pound only if the cells and packaging hold the weight down, which is exactly what the ten-cell design is trying to do. Both packs carry a four-position LED fuel gauge, a small detail that matters on the job: a battery that shows its charge level without a tool display saves a trip to the charger.
Higher voltage tends to mean bigger motors and heavier tools, and the new reciprocating saw and circular saw in the launch look built for heavy duty. That weight shifts storage decisions too. A kit that rides in a truck every day needs a different home than a kit that lives in a shop, and the choice between tool box storage versus tool bags follows the size and weight of the tools.
Cells, Not Just Volts
Cell choice decides how a battery performs. The 18650 cell is the workhorse of the industry: proven, cheap, and available everywhere. The 21700 cell is roughly 40 percent larger by volume and stores more energy per cell, which lets a pack reach higher capacity without doubling the cell count. A pack built on 21700 cells can also deliver higher current for the same internal resistance, which helps tools that draw hard, such as circular saws and reciprocating saws. The tradeoff is weight and cost, which is why brands often mix cell sizes across a battery lineup.
Reading the Amp-Hour Rating
Amp-hours measure how long a pack lasts at a given current draw, not how much power it can deliver. Two packs with the same amp-hour rating can behave very differently if one is built from high-current cells and the other is not. When comparing a new platform against an old one, compare watt-hours per pound and the cell type, not the number printed on the side of the pack.
Voltage Is Not the Whole Story
Voltage describes the platform, not the tool. Two tools on the same battery can deliver very different power because motors, electronics, and gearing decide how much of the battery’s energy becomes cutting force or driving torque. The same 18V system can include two tools with different power levels, such as a rivet tool line where one model pulls harder than the other despite sharing the same battery.
Brushless motors changed the baseline. A brushless motor replaces the carbon brushes of a traditional motor with electronic commutation, which lets the tool software manage torque, speed, and efficiency in real time. The new 40V tools are all brushless, and the brand calls the system smart, meaning the tools and batteries communicate with each other. That communication enables features such as overload protection, runtime reporting, and settings that persist between jobs.
What Brushless Motors Changed
- Longer runtime per charge because the motor wastes less energy as heat.
- Higher peak power in a smaller motor package.
- Electronic speed and torque control instead of mechanical switches.
- Regenerative braking in some tools, which returns energy to the pack.
How a Platform Launch Unfolds
New systems do not appear fully formed. The rollout starts with teasers, then a partial reveal of batteries and a few tools, then a year or more of additional tool releases. One brand showed its hand in stages: first a hint that a new system existed, then the 40V Max announcement with two batteries and a handful of tools, with the promise of more to come. This is the standard pattern for how professional tool brands plan and launch new cordless power tool systems: batteries and chargers first, because nothing else works without them, then flagship tools, then the long tail of specialty tools.
What to Watch in the First Year
- How many tools arrive in the first 12 months; a slow ecosystem is a risk.
- Whether additional battery sizes appear, especially a high-capacity pack.
- What the chargers do: charge time, dual-voltage support, and smart features.
- Whether the brand keeps the older platform alive in parallel, which it usually does.
Building a Collection That Works Together
Platform decisions compound. Every battery and charger you own commits you a little further to one ecosystem, and the cost of switching later is replacing everything at once. The practical version of the question is not which brand won this launch, but which system will still serve a professional tool collection in five years. That favors platforms with broad tool lines, consistent battery support, and a history of keeping old tools running when new ones arrive.
Compatibility rules to check before buying into a new platform:
- Do the new batteries fit the brand’s existing tools, and vice versa?
- Do the new chargers charge the old packs?
- Does the platform cover the specific tools you use, not just the headline saws and drills?
- Is the voltage jump real performance or mostly branding? Compare watt-hours per pound, not the number on the label.
Voltage Ratings and the Battery Ecosystem Over Time
Platforms evolve, and the voltage number on the side of the pack drifts further from the working voltage with each generation. The useful measure is the ecosystem: how voltage ratings and battery ecosystems evolve together determines whether your packs keep working as new tools arrive. The 40V launch exists partly because the 36V platform had run its course; the new system gives the brand room to grow power and runtime without confusing the two product lines in the market.
For the buyer, evolution cuts both ways. A new platform usually means better tools and batteries, and it sometimes means the older platform stops getting new tools. The older system rarely dies overnight, but support slows. That is the moment to decide: stay on the mature platform and buy at clearance prices, or move early to the new one and pay full price.
Modular Systems and Interchangeable Power Heads
The most affordable way to grow a collection is not always a new platform; sometimes it is a new head on a motor you already own. Systems built around interchangeable power heads let one power unit drive a drill, a driver, a saw, and a grinder, which cuts the cost of adding capability to the price of the attachment. That approach fits naturally beside a battery platform: the battery ecosystem supplies power, and the modular heads supply versatility.
A platform launch is the right moment to take stock. List the tools you own, the batteries that power them, and the jobs they do. If the new system answers a need your current one cannot, the early price is worth paying. If it only looks newer, the mature platform on sale is the better deal. Either way, the decision comes down to watt-hours per pound, tool coverage, and how long the ecosystem will keep growing.