We saw lots of new tools, technologies, and accessories at Milwaukee Tool’s NPS17 – their 2017 annual new tool media event.
There was one “reveal” during a tour of Milwaukee Tool’s headquarters that I wanted to bring up for discussion.
What direction will Milwaukee go in for their future next-generation Li-ion battery packs?
Some competing brands have come out with new higher capacity battery packs based on 20700 Li-ion battery cell size. This means the cylindrical cells are 20 mm wide and 70 mm long, compared to 18 mm wide and 65 mm long for today’s extremely popular 18650 battery cell form factor.
But we’ve reached the end of the road for 18650 battery cell development. The battery cells in today’s cordless power tool battery packs are as good as they’re going to get.
So what will Milwaukee do, if they want to make anything better?
Milwaukee has considered stepping up in size to 20700 or 20650 cells for their next generation of highest capacity battery packs, but decided against it.
They will be going with 21700 cells, which add an extra 1 mm in diameter to the 20700 cells some other brands have decided to go with.
It doesn’t seem very obvious, but I’m told that 21700 cells offers more desirable balance between power output, thermal behavior, and capacity, and will allow for a longer development roadmap.
Going to 20700 sized cells, or 20650, would still be a step up from 18650 cells, but Milwaukee wants to LEAP up. They said that they don’t want to take any “half steps.”
While a difference of 1 mm in diameter – around 0.0394″ – might not seem like a big difference, I’m told that it’s enough to allow for completely different battery technologies.
There seems to be a big difference in output potential as well, especially thermal considerations. When designing or using power tool battery packs, you want those battery cells to be as cool as possible. Heat is an archenemy of battery power.
With just a little research, I see that 21700 cells seem to be more favorable for upcoming electric vehicles, as least in comparison to 20700. This industry trend seems to have shifted quite recently.
21700 cells are 3 mm wider and 5 mm longer than 18650 cells. This means battery packs will probably be larger than those built with 18650 cells. How much larger? I really don’t know, but we have seen size and weight increases when comparing on-the-market 20700-based battery packs with those built with 18650 cells.
Will these next-gen packs replace the current lineup of M18 battery packs? I really don’t think that’s likely, at least not right away.
But the price of 18650 cells might contribute to this. I was told that 18650 cells are becoming more expensive, which I assume would be due to lower demand. The electronics industry has moved more towards custom-sized LiPo packs, and it seems that major players in the electric car industry want to head in a 21700 direction.
This has the potential to be huge. If the numbers I glimpsed on some web stories are directly analogous to power tool battery packs, we could be looking at a potentially large bump up in capacity and runtime.
Right now, there are a ton of questions.
One of my concerns is this: what happens if Milwaukee comes out with a new breed of more powerful battery packs? Of course they’ll want to build new tools that take advantage of it.
Milwaukee has made it very clear that they intend for M18 tools and batteries to FOREVER be forward and backwards compatible. Yes, Steven Richman, Milwaukee Tool’s President, used that word in his NPS17 kickoff. FOREVER.
But what happens if a tool is designed for a high capacity next-gen battery and is paired up with a compact pack or XC pack? Will it operate in “tortoise” mode, as opposed to “hare” mode?
As I expected, battery discussion wasn’t on the table for the main NPS17 event, at least not these new batteries. All we were shown was a single 21700 cell, for size comparison with an 18650 cell, and that was during the tour of Milwaukee’s headquarters.
But the takeaway for me is that Milwaukee is going to push forward with an even better M18 battery pack.
I suppose this should not come as a surprise. I found a 2015 Samsung press release that mentions:
The 21700 model can have various applications other than e-bike, such as in electric tools, laptops, and more. It is expected to become the new standard in small cylindrical battery usage.
Milwaukee showed restraint in not rushing to come out battery packs built with 20700 cells. Will going to 21700-equipped packs be the right choice?
I suppose that the answer to this depends on whether 21700-equipped batteries are as good as they’re being hyped up to be.
I had really thought we would see the introduction of a double-battery M18 cordless table saw, but we didn’t. I got the feeling that Milwaukee is hesitant to expand towards 2-battery tools.
They are coming out with a 2-battery LED site light, but that’s for greater runtime. Perhaps the One-Key software will “phone home” to tell Milwaukee whether users prefer to power it with 1 battery or 2 (for longer runtime).
How do you think Milwaukee will launch their next-generation battery pack? Will there just be one offering at the highest capacity end (10Ah? 12Ah?), or perhaps they will come out with all new battery packs with higher capacities across the board.
What do you WANT to see in Milwaukee’s next generation battery packs?
Is this the ‘not a secret, but not public,’ information your referenced in a post or comment the other day?
no mention of a 3ah compact m18 battery? that would have been nice
Yes. (He’s talking about a comment I made to this post – https://toolguyd.com/best-new-milwaukee-tools-from-nps17/ .)
This move to 21700 is something I was able to discuss in more detail. I confirmed multiple times, and it was okay to post about, presumably because the move to a larger battery cell is highly predictable.
When I asked them a while back about potentially moving to larger battery cells, I was told it’s something they are definitely exploring.
The XC batteroes are the 3.0 for the M18
20700 aren’t what I would characterize as a half step forwards. Metabo Li-HD, Bosch Core and Dewalt XR6.0 and FlexVolt 3.0/9.0 are all huge improvements over 18650 cell batteries. That Milwaukee wants to go with cells that are physically even larger than those mentioned is pretty wild. The Dewalt XR6.0 is basically the size of a Milwaukee HD9.0 and the FlexVolt 3.0/9.0 are almost comically large.
Showing up that late to the game I would anticipate Milwaukee launching with 4.0 slim packs, 8.0 XC packs and a HD12.0. That would blow me away; announce that at NPS18 alongside a plethora of M18x2 high demand tools like a 10″ table saw, 12″ mitre, etc. and I think you’d see a ton of happy faces. Imagine an M18 HD12.0 21700 cell battery pack attached to a new orbital Fuel Super Sawzall or a bigger, better grinder. A hypoid gear saw replacing corded worm drive. A Gen2 Fuel Super Hawg with higher torque and higher speeds (with the required electronic and mechanical clutches). Yes please.
Wow it’s like you picked the tool wish list right outta my head. Milwaukee will respond with something good I’m sure, but it’s just that when storage (which is important don’t get me wrong) is the most talked about item from your big event then you flopped. People should be talking about an awesome lighting solution or saw or hell anything that’s not storage or clothing. Milwaukee seems to be playing the waiting game instead of the leading game. Just hope they don’t start falling behind.
These are pretty great, the only issue with these are the battery life issue. I personally find that ACDelco has the best battery life when it comes to anything cordless. Check them out if you haven’ t already.
Koko the Talking Ape
Any idea why the 21700 cells have the advantages they do? Is it just from being larger? Larger cells have less surface area per mass, so they need less case material for the same mass, so presumably, they can be lighter and have more capacity for the same total weight.
But that also means they should have a harder time shedding heat (the same way large dogs do, for instance.) Do the 21700’s somehow generate less heat per unit mass?
The batteries have a foil wrapped up in them if I’m not mistaken…so a larger diameter cylinder can hold far more foil, so batteries can be much more energy dense, but the larger surface area of the battery dissipates heat more efficiently.
Yeah i think that’s right. Older chemistry batteries were typically had a cylinderical interface, whereas these have a jelly roll construction. A slightly larger cell provides much more surface area in that design, but the exterior surface area (and hence heat dissipation) would scale slower than the power growth so i’m not sure how that works. He did mention in the article that they said it enables entirely new chemistries so it may be a different lithium battery technology entirely. Some are better suited to high power, etc.
The larger surface area dissipates heat more efficiently at the same load, with the same number of cells, but otherwise you have it backwards.
For the same capacity, the larger cells have less surface area and so heat up more at the same load. If they then leverage the cells’ higher current capacity to power higher loads, they’ll heat up that much more.
However measuring temperature is not a terribly advanced topic, they would definitely factor this into the design so no thermal limits are exceeded in normal use.
But here’s the question: which is greater?
Thermal output reduction due to larger battery cell volume? Or Reduced thermal shell surface area compared to cell capacity?
If thermal output is reduced due to the larger cell volume, than having a larger but proportionally lower external heat dissipation surface area might not be as significant.
In other words, let’s say the cell generates less heat – not unexpected for a cell with the same capacity but larger reaction volume. More thermal dissipation should add to compounded benefits, rather than looking at it in terms of surface area compared to internal volume.
Ben and I were talking about this. Part of the reason could be the greater “skin” surface area, resulting in a higher thermal release, keeping the cells cooler.
Over drinks and dinner the next night, the product manager discussed the cell form factor a little more, and mentioned how the added space allows for different technologies and manufacturing, which gives the form factor greater potential than 20700 cells.
This not very obvious to me, and I will have to dig deep into scientific and engineering literature to understand it better.
I found a way to potentially understand it. Let’s say there’s a spreadsheet you’re trying to print, but a large column gets clipped off and pushed to a different page. A very small increase in page size or decrease in margin size can change everything, allowing that extra column to fit.
He suggested that there’s greater space for the electrochemical reactions, resulting in lower heat output to start.
Koko the Talking Ape
“Part of the reason could be the greater “skin” surface area, resulting in a higher thermal release, keeping the cells cooler.”
That would make sense, except that as the cells grow in volume, the amount of skin area PER VOLUME (or mass, as I said earlier) decreases.
So suppose I have a cubical cell with volume of 1 in^3 (for convenience). I have a cube of 1 in x 1 in x 1 in. The total surface area is 6 in^2 (six sides, each with an area of 1 cm^2.) So the area per unit volume is 6/1in, meaning that for each cubic inch of volume, there is 6 in^2 of surface area to radiate out whatever heat is created.
Then , suppose I increase the the volume 8 times (for convenience). Then, assuming the cell stays cubical, I have a cube that is 2in x 2in x 2in. The total surface area is 24in^2 (six sides, each 2 in x 2 in, or 4 in ^2). So the surface area per unit volume is 24/8, or 3/in. Meaning, now, there is only 3 in^2 of surface per unit volume to radiate heat out, instead of 6. It is now twice as hard to get rid of excess heat.
The effect grows as the volume grows. As the volume grows, the surface area grows, but MORE SLOWLY. As the volume gets larger and larger, there is less and less surface area PER VOLUME to get rid of heat. As I said, that is why large animals, like large dogs, have a hard time getting rid of excess heat.
If I had, say 12 in^3 of lithium chemistry to work with, I could divide it up into 3 larger cells, or 4 smaller cells. Four smaller cells might not last as long (depending on how the cells are connected, and other factors.) But they would be easier to cool.
Stuart, I think the product manager is still “marketing” a bit. Bigger cells (or more of them) are under less strain for a given load, so they shift towards “capacity” type chemistry from “output” type chemistry.
The physical size is the one thing they can hang their marketing on, and we all know Milwaukee love their marketing… give them an inch and they’ll make it look like a mile.
It could be.
But discussions with product category VPs, Product Managers, and engineers are as unfiltered as things can get.
It’s not rehearsed, polished by the marketing and communications teams, run through legal, or otherwise.
The move to 21700 cells is not something that is being announced or discussed yet. I double and triple checked it was okay to post about.
It started with “this is what we use now, and this is the direction we’re headed,” as part of a small general Milwaukee Li-ion presentation outside the battery research lab where this talk is generally given.
Ben and I started talking about it between ourselves, and then we asked some questions. The next day I asked some more questions.
I am thoroughly convinced that Milwaukee sought to vet multiple upgrade paths, and they settled on 21700 over the other options.
It’s not a numbers game, it’s one of performance and runtime.
When the new Milwaukee batteries are announced and released, whenever that might be, will they discuss how the battery cells are 5% larger than the ones in competing packs? I don’t know, but I don’t think so. I think their focus will be about “our new next-gen batteries are BETTER,” and they might very well be.
From what I understand, taking what Milwaukee told me to conduct some basic research online, the cells Milwaukee intends to use for their next-gen packs DO provide a competitive advantage compared to what other brands are using.
For all any of us are aware, Dewalt, Bosch, and other brands might ALSO be prepping to move in a 21700 direction. Maybe they’re just at 20700 so as to have a better product now, and they could have 21700 in mind as the NEXT step.
Those I spoke at Milwaukee called 20700 a half-step, and the product managers at Dewalt and other places looking towards the future might very well believe the same thing.
The question as to whether one should take a half step now, or full step later is a tough one.
All very true. I was just suggesting that, knowing Milwaukee, they will likely make more of it than what it is; a 10% increase in cell volume.
I’m not one for salesmanship, so terms like “Red Lithium” irk me. There’s absolutely nothing special about Red Lithium batteries (they use the same cells as everyone else) but Milwaukee devotees repeat this marketing material like it’s scripture.
Maybe the 21700 cell based batteries will be called “Blue Lithium” or some new nonsense.
Don’t get me wrong, I like Milwaukee tools, I just hate their marketing. DeWalt is even worse with their “max” battery voltage.
Looking at my email history, I received the RedLithium press release back in September 2010.
At the time, RedLithium batteries were better than those that preceded them, providing benefits in performance and durability.
· 40% More Run-Time
· 20% More Speed
· 20% More Torque
· Fade Free Power
· Operates Down to 0°F/-18°C
· Runs 20% Cooler
· Up to 50% More Recharges
· No Memory Effect
So at the time, RedLithium was a way to differentiate what was available, and what was emerging.
I guess the branding stuck.
They also have XC branding for their higher capacity battery packs, and HD for their new 9.0Ah.
But I can say this – their branding makes things easier to understand.
Dewalt changed the color of their battery packs – black I guess for basic, yellow for the newer and higher capacity ones.
The new FlexVolt batteries seem to have the same color scheme – black for basic, yellow for premium. I believe someone at Dewalt used the “basic” and “premium” labeling, I don’t remember.
That stuff was all true, compared to previous versions of their own batteries (NiMH maybe, or the abandoned lithium V12?). Those numbers were not true relative to their competition.
I guess their branding really did work! And my point is made. 😉
No, compared to their previous M12 and M18 Lithium battery packs.
” Fully compatible with all M12™ and M18™ cordless products currently available, the new REDLITHIUM™ batteries will provide up to 40% more run-time, 20% more power and 50% more recharges than other Lithium products. The new technology will also operate in extreme temperatures as low as 0°F/-18°C and will run 20% cooler with fade free power and no memory effect. In short, users are able to instantly upgrade the performance, run-time and durability of the M12™ and M18™ tools they already own, simply by switching to the REDLITHIUM™ battery packs.”
Maybe this when new Li-ion packs started to overcome cold weather limitations, I don’t really remember.
That’s a crafty piece of writing you’re working with there, Stuart!
“Fully compatible with all M12™ and M18™ cordless products currently available, the new REDLITHIUM™ batteries will provide up to 40% more run-time, 20% more power and 50% more recharges than other Lithium products.”
“other Lithium products” has no relation to M12 or M18 tools. See what they did there? Somewhere there existed some lithium product made by somebody that was crappy enough to allow them to make that statement. They were not talking about their existing batteries.
“users are able to instantly upgrade the performance, run-time and durability of the M12™ and M18™ tools they already own, simply by switching to the REDLITHIUM™ battery packs”
Here they are simply stating that the REDLITHIUM packs are better than their previous design, not stating by how much. They are not relating to the percentages given earlier.
These press release statements didn’t just happen in casual conversation, they were designed very carefully (as are most things of this nature these days) to deliver very specific information in a very specific, and misleading way. What’s funny is, they are STILL saying this same stuff all these years later! Check out the M18 battery page here:
You’ll see the original quote is pretty much unchanged! They now call it their “exclusive line of REDLITHIUM batteries” as if they somehow are the only ones privileged enough to have access to them. Wow… all these years later and REDLITHIUM is still up to 40% better? Nobody’s caught up yet? That “REDLINK intelligence” must be light years ahead of everything else to get 40% more juice out of the EXACT SAME Samsung/Sanyo/Panasonic/LG 18650 cells that everybody else is using. For the record there’s no such thing as a REDLITHIUM battery, it’s a Milwaukee trademark only.
Sorry Stuart, I don’t like being a hardass but the marketing foo is STRONG with this company. I’m looking forward to seeing how creative the marketing team can be with their next-gen batteries based on the 21700 cells. My bet is “BLUELITHIUM”, or without the “E” for “BLULITHIUM”, that way their tools can not only be even more “technically” superior but also more patriotic with a RED, WHITE and BLUE color scheme. LOL
I gotta say it again for clarity, I’m a BIG Milwaukee fan. I have a large collection of their M12 tools and I plan to grow it even further. They really are terrific tools and it’s the best 12V platform going right now by a long shot. I love my 18V Makita stuff even more, but a good friend of mine who had a few older Makita 18V tools just switched to the M18 stuff and he’s thrilled with it. Just gotta say that so I’m not seen as a hater, that’s all.
I don’t like marketing. I like to research and buy my tools, not have them sold to me. There’s a big difference. 🙂
I do hear what you’re saying.
All brands have marketing messages they want to spread, you just have to cut through it.
I don’t remember the last time I wrote “RedLithium.”
Bosch moved to 12V, but only in Europe. Here, it’s still supposed to be 12V Max.
I can’t tell you how annoying it is to have to write out 20V Max or 12V Max all the time. But what can you do?
At least it’s easier and neater to write FlexVolt than 60V Max and 120V Max.
Branding is important. It can be annoying, but so can the absence of clear branding and differentiation.
As a tool blogger you might have to resort to acronyms, lest you wear out your keyboards too quickly!
As someone else mentioned. As size increases. Relative surface area decreases. There must be more at work in the internals of how the cells are assembled that impacts thermal properties.
Maybe we’re not there yet – but we may need to start working out at the gym to build up our “Popeye-the-Sailor-Forearms”. At some point these batteries are going to get so heavy that they will only make sense for tools that have their weight supported by something other than your wrist and arm. For a new crop of cordless saws, belt sanders, stationary or benchtop tools and some OPE tools – added power may trump added weight – but a drill, omt, glue gun or other handheld tool may become unwieldy. How about a 120V fan-cooled backpack battery powering a plug-in tool?
An exoskeleton robotic assist arm with interchangeable tool heads? I have a feeling we won’t have to wait too long before we start seeing those. (;-D
All the battery backpacks I’ve seen so far seem to be aimed at absurd capacities for all-day OPE runtime. How about a smaller pack, even a belt pack, with a 15-20 Ah capacity and cable leads? Possibly even just an adapter unit to slide 2 or more M18 batteries on.
Especially if they added an 18-10.8V step-down circuit to power M12 tools, that could be HUGE! Especially for those of us already invested into both systems, but also for Milwaukee by encouraging people still happy with their M12 tools to buy into M18.
Fred, exactly! Ten years after 18650 lithium powered tools started storming the market the batteries all of a sudden start to grow by 50% in both size and weight? Where are all the smaller lighter more compact batteries that science has been promising? All of a sudden a 15 cell battery is OK to put on a drill?
OK, OK, I know the bigger batteries are aimed at the bigger more powerful tools, it just seems so backwards to go way up in size at this point. With the smaller tools like drills and impacts I’d rather have two smaller batteries than one big one.
The belt pack battery would be a perfect solution for those guys who absolutely need all day run time on a tool. Only then would a 9.0HD powered impact driver be practical, in my opinion.
Regarding OPE, the power tool battery platforms just aren’t up to the task. For light load tools maybe, like string trimmers and such, but for heavy hitters like blowers, mowers and snowblowers the big battery platforms are where it’s at.
No 10 or 15 cell power tool battery is ever going to compete with a 28 or 42 cell OPE-specific battery like you get with Ego for example, and their stuff is much cheaper than the Fuel OPE. This is one area where a larger battery platform just makes sense, both in price and performance.
Like anything else, when you have to use your muscles for a new task, you’ll be sore for a while but build up those muscles.
Besides I see it more as a change in direction from continuing to put more and more series of cells in parallel. Suppose they just use two series of 21700 in parallel instead of three series of 18650, or their intention is primarily to use these packs in stationary tools like saws, or lawn/garden and lighting, fans, radios, etc.
I have to admit, I was expecting a larger number of multi battery tools the way that Ridgid, Ryobi, and Makita have done. But, improving the battery itself is more in line with what Milwaukee can do to be leading edge, rather than simply copying other companies. Makes sense that they will keep this fairly quiet until it’s ready. Just enough information is released to keep consumers from jumping ship, but not enough to give away proprietary engineering information.
I also like their compatibility promise. So many positives for the company and consumers, it makes good business sense. It just comes down to giving consumers confidence that the tools they buy now will last them for a number of years. They also need to make a similar promise with OneKey. The more that cordless tools become connected devices, the more that software upgrades, patches, and ongoing support become required.
Going forward, as technology, both battery, and software, advances rapidly, it will come down to ensuring that a tool life cycle is determined by durability and performance, not unsupported batteries, or software.
This is exciting news though. This will allow companies to provide credible cordless options for a number of new tools, and improve performance on other common cordless tools. Both of these steps forward drive sales in a big way as well, so the market will continue to incentivize these developments.
Thanks again for bringing us this information.
Any speculation on what this means for the m12 series? Will those batteries get larger as well? More power? Or is the new battery tech not compatible with the 12 batteries?
I would guess the 21700 form factor, which is 3mm wider than the 18650 style, is incompatible with M12. M12 has 3 18650 cells in the stempack which inserts into the handle of the tools. Adding 1/4″+ to the diameter of the pack is likely a no-go.
M12 could use an empty stem as an adapter, and have the batteries in a flat plate pack at the bottom, if they want to keep that series compatible too.
The XC packs use 3 18650 packs in the stem and 3 more in the base; your suggestion either halves the number of cells in an XC pack, or gets M12 batteries closer in size to M18, in which case I would basically always grab the M18 with a slim pack.
That was beyond the scope of the conversation.
I don’t think they’re aiming for the M12 platform to be much more powerful.
I don’t think the 12v line needs more power. More tool and smaller tools is the way to go.
They actually need to get the grip in the 12v line a little smaller to be comfortable all day long. ……and i have large hands!
I mentioned it. I find the handles to be a little chunky.
My hope is that Milwaukee eventually moves to a slide pack, and also creates a slide pack to stem pack adapter.
I sincerely hope they don’t move to a slide pack! If they did, there would be a lot of unhappy people. The last thing I want is to have to use an adaptor. That’s just a bodge in my opinion.
I have medium sized hands (size 9 glove) and I don’t have any issue with the grips on the M12’s and I do use them daily for work. Sure, they are thicker than some but they are far from being terrible.
Not sure if it’s too late but what would have been nice to see is possibly a battery limiter or something for high end tools that wouldn’t run with say the compact or even the 4 and below XC packs. The larger ones would work with all of the tools but the lower packs wouldn’t fit into the high demand tools. 50/50 on this being a bad move because you wouldn’t be able to use all of your batteries with all of the tools but on the flipside you wouldn’t be plugging in a 1.5 pack and then complaining because it doesn’t have much power/runtime. Be a way for Milwaukee to guarantee performance. Also this could lead to them making giant packs for tools you wouldn’t notice the weight on. Like 15 26650 cells for a minimum of 16 amp hours for a table saw…
Also, why the odd size for new batteries? I would think 26650 would be the next natural step because the pack would stay the same length at least. With some more adoption those should easily hit into the 6+ amp hour ratings.
I was really hoping to see also some higher capacity compact packs but at least a rapid charger has helped with that. The fact that the 6.0 XC could be made easily into a 3.0 compact with almost no effort seems a little crazy they didn’t refresh those batteries. While longer runtime is always nice there’s a point where it’s just too big of a battery, like pointed out above.
Listed capacity range for a 26650 is only slightly wider than a 21700 (3300-5200 vs 4200-4800).
As for dimensions, the cells aren’t arranged longitudinally (in line with the long axis of the battery) but transverse (in line with the short axis). As such you’d either end up with a much taller battery (with more dead space in a basic 5-cell unit) or a much longer battery, with the same width as the current models. There’s a good illustration of Milwaukee’s battery layout at http://blog.steinerelectric.com/2015/02/milwaukee-tool-m18-fuel-line/
Yup, my bad. Was thinking battery length and pack length. But yeah, battery length = pack width, not pack length. The 26650 would create a longer pack but not a wider pack.
Wish the 26650’s had more density though since an 18650 is close to the capacities of the 26650 but really should be double the capacity. The volume of the 26650 is still 1.42 times more than a 21700 so imagine if the density was the same…I come out with 6800 mAh for a 26650. Battery would only need to be 1 3/4″ longer or somewhere taller than a slim but not as tall as the XC so you could offset the stacked configuration. Eh, just thinking out-loud here.
No changes to the m12 system, correct? I don’t see any way they can upgrade from the 18650s for the m12 tools, since the packs wouldn’t fit inside the tool handles.
I always thought their were 3 cells in a M12 compact battery. Would they be able to go down to 2 upgraded cells & still use the same form factor? probably not.
And as much as we are talking about more power, many of the tools don’t need it. So I am looking forward to more efficient compact batteries, rather than what’s the largest battery I want to lug around unnecessarily.
You wouldn’t want to go down to two cells because of the voltage penalty. Already I question the need for their M12 line, when they could just use 14500 cells for a smaller M18 pack.
The thing is, you don’t want massive current which you approach with lower voltage and the efficiency loss from more voltage drop as current increases, then there is also the battery impedance.
Generally you want the lowest current at highest voltage that can do the job, but there are the factors of safety, cell size vs # that make a pack high power density, and of course total cost.
On that front, don’t expect the 21700 packs to be inexpensive. The race to beat the competition will come with a high price tag.
14500 cells have a higher cost/capacity ratio than 18650’s, and they perform much worse. Mass-market power tool capable (read: high drain) 14500 cells don’t exist. They could be custom made just for Milwaukee, but they’d be incredibly expensive.
I wouldn’t think a change is possible either due to the configuration of the battery fitting inside the handle. Only upgrade will be top performing 18650 x number of stacks. So they could come out with a 9.0 but it the base would be double the current height. I see M12 as being built for light weight not massive batteries.
So my understanding was the tradeoff of 20700 vs21700 started off with who is your supplier. one company introduced the 20700 while another introduced the 21700
which is comical as it’s 1 mm different which if I recall correctly is also the max tolerance allowance on the cell envelope.
the battery pack that takes 6 20700’s probably also tolerates 6 21700’s. so the “advantage” won’t last long if any.
as far as being more energy dense, better throughput, etc – sure of course they are – they are bigger. But not that much bigger. 1/20 of scale.
I do applaud their thoughts and comment about keeping the M18 alive. I do however start to wonder if they will make the transition to another voltage line for larger tools – vs going the double battery route. Instead I see them going double battery – and putting in circuitry in the back to ident to the tool full capacity or lessor capacity.
I like the idea of “forever” compatibility. It’s ridiculous how much waste is generated through obsolete batteries and chargers. At least keep the interface the same if you’re going to change the cells. They should stick with a really good platform for at least ten years and then make a major upgrade…going two sizes up on the cells will keep competition at bay and will allow them to focus on the tools themselves; brushless motors and wifi/software will allow upgrades along the way.
As was mentioned, better cells means you can prob slim things down. The current m12 line is giant compared to other brands…so perhaps make a smaller form factor for a truly subcompact tool. I think they were onto something with the m4 size/form factor, it was unfortunately a third battery platform no one wanted to purchase.
Wait until you hear about the newest platform – RedLithium USB. =)
I have always wondered why tool batteries use cylindrical cells as opposed to flat cells like cell phones use. It seems like they could squeeze more capacity by filling up all the space. Apple does this in the MacBooks by using layers to fill every little spot so they can make a battery shaped like the enclosure that encapsulates it.
Durability and economics?
Plus, a brand can design a pack and have several potential sources for cells, such as Samsung, Panasonic, Sony, and I guess Tesla eventually.
The cylindrical batteries are more durable and safer for an application like a power tool that you know is going to be abused.
Lithium Polymer packs like you see in electronic devices are not nearly as durable and have higher risk of failure and explosion.
Big round of applause for “Milwaukee has made it very clear that they intend for M18 tools and batteries to FOREVER be forward and backwards compatible.”!
The context was about the mindset when they were first developing the M18 platform, but everything they say suggests that the “forever compatibility” mindset is here to stay.
I’ve heard from a very reputable source. That a m18 table saw is coming. Late this year or early next year. They are close to test phase. I hope to get a prototype to test for them. It wouldn’t surprise me that this saw would incorporate the “new” syle battery. While still being backwards compatible with the “older” m18.
I know it’s something they are definitely working on*, but I don’t think they’ve made decisions about its direction yet.
I thought it would have been announced at the media event, but I guess it’s just far too early in the development process.
*Nobody explicitly told me it’s something they’re working on – I’m presuming it’s something they’re working on. But knowing what I do about Milwaukee Tool and how they operate, I can’t imagine that this is a challenge they’re not already attempting to tackle.
I agree. My source also said that there was a chainsaw coming out in the same time frame. Having 2 tools that require more power can’t be easy with working the the current generation of batteries, which as you said. Has reached its peak. I’m red tool thru and thru. Being a Milwaukee native helps. I get to test alot of goodies before they are released. 🙂
Do you think they might be waiting on where the CPSC comes down on Active Injury Mitigation technology?
I think we’ll see higher capacity batteries with the new cell size along with dual battery tools from Milwaukee. This would allow for more tools that are typically corded, ie Ridgid’s air compressor, and other high load start up tools. Just my thoughts. …..
I think that’s going to be the big divide in the market for a long time. X2 tools from everyone else – and Flex Volt from Dewalt. And they they both have their pros and cons and I sort of think it’s a great thing for us. Keeps the innovation moving
This has been a great thread to read through – technical (geometry, algebra, physics, chemistry), functional (battery packs being larger than the tool itself just to get all day run time), light-hearted & foreboding (robotic arms), truthful (marketing is hype-deceptive BS).
Let me pretend to be a millenial (30+ years too late) – why do I have to wait 1.5 hours for my 40V Ryobi battery to re-charge? I can’t out tweet the twit, snap that many chats, insta that many grams and nobody faces that many books anymore! I want instant gratification – craft beer with my organic beef, craft cocktail with quinoa infused energy drink – I want these great advances in battery power and run time to charge QUICKLY!
Was that discussed at all – decreasing charge time so I can actually get some work done? Or do we maintain the current approach of forcing the consumer to buy multiple batteries (often more costly than the tool itself) just so they can complete the task at hand (not robotic hands mind you).
An outlet, a well made extension cord and my Makita corded tools keep looking better and better all the time. So far SoCal Edison hasn’t raised rates too much due to all the Tesla loving hipsters – which thankfully affords me luxuries like Justin Timberlake hats, tats and ‘stache wax! 🙂
Seriously – I’m off to HD to buy another Ryobi battery @_@
Heat is a battery pack’s greatest enemy. There are faster chargers out there, with active cooling, but there has to be a balance between speed and longevity.
I can say that milwaukee tools are one of the best (even 1#), but their ‘smart’ batteries are actually designed with the purpose to prevent you from replacing defective cells. If you disconnect the circuit board from the cells, an IC clears its content permanently and you end up with a useless battery.
As far as the cells go, I see that the 4Ah ones have Samsung 20Q or similar inside, while the 3Ah ones have Samsungs 15Q cells. So nothing special here. The circuit is theirs, not the cells, and it’s over-complex.