This guy has a few videos on his channel dedicated to the batteries.
The videos at the bottom of the article have most of the details, since those dive into the communications protocols as opposed to the raw schematics.
The M12s have the pins too for voltage sensing in the charger (and tool maybe?), but they have 1 mega ohm resistors in line so cannot be used for balancing.
We have about 10 of the M12 batteries, about half are the 3 cell ones and half the 6 cell larger capacity ones. And every single one has gone completely out of balance within 2 years of use.
I plug them into a balancer and they last another solid 6 months or so.
There's also the risk that tool prices could go up as I suspect some tools are currently sold as a loss-leader to get you into "the system".
I have seen 3rd party battery accessories so anyone looking to make money might wind up making adapters to retrofit tools. Good for the environment too.
That will drain the battery by itself over time. So you then must make sure to remove the battery from the adapter as per instructions.
That is just so dumb, it's beyond my understanding.
Also: I want that regulation :)
I tried to standardize on one system (Hikoki 18/36V). This was great as they use the same battery across consumer and pro products. But I moved from Japan to Europe and they are far less available, and more expensive. Now I buy Parkside stuff (Lidl brand) and they are probably a tier lower but better value and also use the same battery across consumer and pro products.
Anyway I felt lucky that I could buy both low and high(er) end cordless tools in two countries/brands and also find adapters to use both batteries in both sets of tools. Both systems don't have any sort of data handshake between tool and battery. Going forward, this will probably increasingly be the case so I would love for a standard to be enforced.
Some listings go so far as to be worded like “electric drill for Makita battery”.
And then not as any sort of special deal, just the standard retail bundle, the lawnmower with four batteries included costs $700. So that's $560 of batteries and $140 of lawnmower.
It's funny how lithium ion cell prices have absolutely cratered everywhere else, but the price of tool batteries just keeps going up.
I wish there was somebody making reputable quality compatible tool batteries instead of mystery brand counterfeit trash.
No company actually wants to make it easier for people to buy other tool brands.
With brandless batteries, it's luck-of-the-draw, but overall, as much as I do wish there were some way to know what you're getting, I've had good luck more often than not.
What's also been nice is the rise of adapters. My Bosch blue batteries now fit many places they didn't used to.
Some of these brandless Chinese makes are really solid, high quality products, but you can't easily tell which ones because they're visually indistinguishable from the bad ones.
Seems like the tool batteries might be the new ink cartridges.
Tool batteries as a general rule don't do anything fancy internally, so they are easily substituted. I suspect it's mostly a matter of the main buyers being tradies/workers who use them to make money and thus don't care that much about the expense of the batteries - they probably aren't replaced that often.
Would be nice if there was a 3rd-party seller known to use quality cells though, rather than unknown off brands.
It feels like there is a segment the tool co's are selling toward, that leaves another segment underserved.
Eip if this is something you want to hobby-horse on.
Batteries which are used regularly and spend more time between 20–80 percent full might be less "abused" than batteries which are used infrequently, and stored in a room which sometimes gets hot.
As a homeowner I’ve had Ryobi lithium batteries for over a decade. Other than having added a couple battery packs from deals and a couple batteries from tools, I’ve not had a single one of my batteries fail. All are being stored at the maximum charge. Some don’t last quite as long these days, to be expected with age, but not one has actually failed even from being dropped off ladders onto concrete. I did, however, have a Dewalt at work that died from falling 4 feet to the carpet floor. I’ve only had one Ryobi tool fail in that time, and those circumstances were questionable since someone had borrowed it.
Experiences are localized and subjective.
I was a little annoyed that some of the Milwaukee tools require you to go with the M12 battery (the "bandfile" is what sucked me in) so now I've got 2 battery ecosystems for the tools, but I guess that's not the end of the world.
I almost went with Ryobi when I did my recent refresh. But I've changed to doing way, way more with the tools, I'm basically using them every weekend now. And the Milwaukees are just a joy to use, though you do pay for that. One benefit I didn't realize when I bought the hammer drill: It will detect if it grabs and the tool starts spinning. I was using a mini auger to break up some soil and the Porter Cable I nearly broke my wrist when it grabbed. I got the Milwaukee partly because it had a second handle you could add, but the accelerometer worked even better than that.
Where it gets fun are the "buy a battery pack and get a tool free" deals. I had a bunch of text typing this out, but the stickied Reddit post covers it better[1]. You can typically get the tool you want for 40-60% off when/if it goes on sale using the "Home Depot Hack". Most common tools do at least once a year - the esoteric items are more hit or miss.
I rarely pick up a tool now at full price. Once I know I want one, I simply add it to a list and note when it goes on sale in one of those combo deals. I've also picked up way more batteries than I ever will need due to other sales as well.
The Milwaukee "buy more save more" event also works well if you need what is going on sale at the time.
Reddit /r/milwaukeetool is a good place to check in from time to time for sales. Slickdeals is great for setting up an alert, but the exceptional deals get sold out quickly once it hits that site. There are also Discord groups out there as well if you go deep down the rabbit hole.
Warning: Once you learn about Packout this becomes somewhat of an addiction for certain personalities.
[0] https://old.reddit.com/r/MilwaukeeTool/comments/1gwhvi9/the_...
Sadly one of the best ways to get cheap Milwaukee M18 tools is the “hackable” sales from Home Depot: when 2 SKUs bought together makes them both cheaper, but if you buy them online and have the 2 SKUs sent to different HomeDepo stores, you can cancel one of the SKUs later and the non-cancelled one is deeply discounted. It’s probably a violation of ToS, but customer service reps allow it and support it, so maybe it’s not actually a violation… ? It feels like corporate may eventually ban users who abuse that and cost more money than they are worth.
Milwaukee doesn’t sell via Amazon or eBay and there are notoriously good Chinese clones on those sites.
I did get 3 decent Milwaukee (mostly M18) deals on Woot.com, but you have to jump on those quickly.
There is a great website that does good price history + price comparison between HomeDepo, Lowe’s, and WalMart but I can’t find the link. If anyone has it, please share.
I've done this at least a few dozen times over the past 4-5 years now. I have way more tools than is reasonable for my use-case. No problem so far.
From what I can tell HD doesn't seem to care much - the margin on these things has to be insane, so they are likely still making money on the transaction. Given how the discount is pro-rated across both SKUs you apply the deal to they likely did that on purpose. Who knows what rebates they are getting on the backend from Milwaukee on such promos, but I'd be surprised if there were none.
I imagine if you did this a dozen times in a given month they might ban you for outright suspected return fraud - but for most folks I don't think it's a major concern.
This is true of all modern lithium ion consumer hardware, because if you don't get this part right, the battery explodes and burns down your house the first time.
Their batteries, at least in my experience, have also been similarly long-lived and reliable over years. And yeah - like some others have said - I also get all my batteries from 'battery included' tools/deals. I don't think I've ever bought one by itself.
After that, neither pack would hold a charge long enough to be useful. Which I thought was pretty disgusting. Come to find out, this was basically the normal standard to which Craftsman had finally sunk. Rather than do the rational thing and throw it out, I held onto it with with a grudge and a goal of actually making it useful again one day.
A few years back, I found a decent deal on brand-new 18650 high-current LiFePo4 batteries from a reputable supplier ($2.50 each, sadly NLA) and bought up a bunch to remake the packs for this drill and a couple others I had laying around for similar reasons. I added an inexpensive but well-made BMS (which I tested thoroughly before implementing) and the voltage was upped to 16V nominal for a little extra kick. Don't ask how I spot-welded the tabs to the batteries.
4.5 years later and these drills are still going strong, I use them at least once a week on both small and large projects. They are not speed demons or torque monsters, but they drill all the holes I ask them to. Would I have been better off economically throwing these ones in the garbage and just buying the cheapest thing from Harbor Freight? Maybe.
But spite, it turns out, is its own reward and I would do it all over again a heartbeat.
In my case, Craftsman just used REALLY bad cells, Plus there was no BMS, AND they wired them all in series so that if one or a few develop high internal resistance, basically the whole pack was shot. Very bad design + very cheap cells = designed obsolescence.
Pretty amazing compared to what all batteries were like growing up in the 90s.
There are vanishingly few AC-DC power supplies that can push 600W (that’s 50 amps at 12V), let alone 1620W (90 amps at 18V) or 3240W (180 amps!!) and definitely none with a USB-C plug on them. You’d realistically be limited to ~1500W on standard household receptacles, and you’d need some hefty cables on the output side of your power supply, especially if you want them to be jobsite-safe. For reference, 180 amps is in the same ballpark as EV fast charging stations; that’s a rough estimate on the size your cord would have to be plugged in to the bottom of the tool.
For the super light duty stuff like an M12 dremel, sure it’s doable. But for any tools that need high burst or sustained power, either a battery or just running the tool on 120V AC directly (or compressed air) is easier, cheaper, and probably safer.
[0] https://docs.google.com/spreadsheets/u/1/d/e/2PACX-1vRghl-44...
For perspective my DC welder is rated at 10000 watts of input. The efficiency is really poor however so I'd only see something like 4000 watts out in the best conditions.
For automotive Milwaukee is the clear winner.
DeWalt's lighting options are terrible, compared to Milwaukee. Low run time and bad ergonomics.
In contrast, Milwaukee lights run much longer and have some neat solutions for disaster scenarios (lamp + USB charger).
Am I in danger?
Liftyee•1d ago
Interesting to see a microcontroller (and quite a classic one...) as well as an ASIC for battery management. I imagine it's for communication purposes. The battery management chips I've been looking at have built in I2C interfaces to let me avoid firmware.
alnwlsn•1d ago
thephyber•1d ago
rapjr9•21h ago