A reader brought up a good point in reply to our post on the new Milwaukee M18 dual port Rapid Charger.
As with all Li-ion batteries I’m familiar with the charge cycle rate seems to effect the actual battery life span.
Slow(er) recharging seems to prolong their useful life while faster recharging tends to shorten the actual useful battery life.
Has anything changed with all these newer power tool commodity cells?
That’s a great question! Will faster charging rates, as with Milwaukee’s M18 Rapid Charger or Super Charger, shorten the life of M18 Li-ion batteries?
I touched upon this in my Milwaukee M18 Super Charger post, as it came in the comments section. I also followed up with Milwaukee, who provided the following insights:
This [super] charger does not have a negative impact on battery life. This is why packs outside of High Output will not charge faster vs rapid. The high output packs can handle this faster rate without degrading life due to the chemistry and mechanical design of the cell tech.
I would assume that the same considerations were made when they designed the Rapid Charger, which preceded the Super Charger, and this dual port Rapid Charger which came later.
They also provided the following:
No, there won’t be a difference in lifespan of batteries between standard, rapid, and super charger. Packs outside of High Output have a ‘cap’ where they simply will not charge faster on this charger. That ‘cap’ is comprised of many things, like cell chemistry. The high output packs can handle this faster rate without degrading life due to the chemistry and mechanical design of the cell tech.
How do they know? How can they be sure?
Here is where a smile comes to my face. A couple of years ago, my visit to Milwaukee HQ, as part of a past new tool media event, we toured the battery lab. I looked around and took note of all the testing setups and battery charge-discharge stations.
Then, for the NPS19 tour of Milwaukee Tool headquarters, we got to visit the battery lab again. Unfortunately, we didn’t see the battery failure and explosion-proof lab, which was moved to the other building. Maybe that’ll be a treat for next time.
I asked (begged) for permission to walk around the lab during the usual “intro to Milwaukee M18 battery pack technologies” presentation, which was at the front of the room, and with my wish granted I did a few laps through the room with my hands firmly down at my sides or behind my back.
I asked a couple of questions about what I saw, and filled in other details based on prior knowledge and familiarity with lab and test equipment.
I can’t share details, out of concern that some of what I saw could be construed as industry secrets they’d like to protect from competitors. Well, I could, but I’d like to be invited back, and brands are more likely to lift curtains if I am discreet about what I see and how much of it I understand.
But I can say this – I was not expecting the level of sophistication that I saw.
Some readers have argued in the past that they believe cordless power tool brands all order some off-the-shelf cells, slap them in a plastic box with a circuit board and call it a fancy battery pack that’s priced a lot higher than the sum of their parts.
Nope. They have ability to control and test the performance and capabilities of their battery packs, down to the finest details possible.
Milwaukee’s cordless battery engineers and product managers would only need a fraction of the floor space to run the equipment needed to verify their charging rates don’t diminish battery pack longevity.
Is it still possible that their faster chargers might affect cell longevity? Sure. But will it be measurable or perceivable to the end user? Batteries are consumable and charge capacity will be diminished regardless of charging rate. But, let’s say there is a slight but measurable different that becomes apparent or even compounded over time. Would all the cycles of faster charging have been worth it? For someone buying a faster charger, the answer is most likely “yes.”
And for the users that receive faster chargers in their combo kits, that’s usually because they’re being paired with higher capacity or next-gen High Output batteries that were designed and launched in tandem with or following the chargers.
Consider smartphone battery tech. What was true for smartphone batteries from 2010 no longer holds for batteries in 2020. Standards and practices evolve over time, as does battery technology.
One might argue that while smartphone batteries have evolved over the past few years, the Li-ion cells in Milwaukee battery packs have not, at least not the 18650-sized cells in most of their non-High Output batteries. That’s true, but keep in mind that it’s still all about controlling the heat and thermal dissipation.
The same designs that help to keep batteries cooler during discharge as they’re put to work will help keep them cooler during charging, and charger tech, sensors, and cooling can aid in this.
Heat is usually the biggest enemy to Li-ion battery cells. Control the charging rate, and you control the heat. I’d bet they worked to dial things in and with a large enough safety margin to ensure that the faster chargers can improve performance without sacrificing battery pack longevity.
Milwaukee Tool knows their stuff when it comes to cordless power tool batteries. If Milwaukee says their faster chargers won’t have negative impacts on battery life, I trust it’s accurate and true.
There’s also the absence of anyone here (or in other online communities and forums that I’ve seen) complaining about Rapid Chargers killing their M18 batteries. There are enough M18 users and enthusiast users that wouldn’t we have heard of any issues with battery longevity by now?
There are downsides to the faster chargers. I came across a battery or two that were neglected for some time and drained too far. The Rapid Charger dismissed them as defective and wouldn’t charge them due to the voltage being too long. But, the voltage sensor in the standard charger has a lower threshold and was able to refresh the batteries, bringing them back up to full capacity and regular use.
The charging rates, safety measures, thermal sensors – everything that goes into these battery packs and chargers are deliberate. Milwaukee knows how far their batteries can be pushed, and they fine-tuned their chargers and batteries accordingly.
Taking Milwaukee at their word (they’ve never given me reason not to) and the lack of of anecdotal complaints has me believing their stance on the Rapid or Super chargers not negatively affecting battery life. And that’s ignoring the level of attention I know they put into their battery pack development and testing, thanks to what I saw during NPS19.
Sure, we *could* verify this for ourselves, but lower-cost testing would involve years of daily A vs. B testing, and accelerated charge-discharge cycling would involve a sizable investment in test equipment, at the least. We don’t exactly have an industrial space where I can build an automated set-and-forget lab bench, let alone the capital needed for the necessary equipment.
I am all for experimentation and third party verification of facts, but I have visited the idea before and high-performing 18V-class battery packs are simply too powerful for the equipment I have available or can reasonably budget for.
It seems contrary to what has been true in the past, that faster charging rates won’t negatively affect battery life, but in the absence of users who have experienced otherwise, it seems fair to take Milwaukee’s claims at face value.
If anyone has ideas on how to test for this without an inordinate time commitment, or a 5-figure test bench, I’m open to ideas.
A bit off topic – but ToolNut seems to have some decent battery deals right now:
That has been the quarter 4 offer, going since November and expires Feb 2 at Home Depot. If you buy in store the 12 will ring out at $107, and the 8 at $91. Keep what you want
So, what’s to prevent any one of the companies from becoming a one-stop for all battery packs? I know, to sell more tools – but if the central component becomes the batteries and their chargers and the tools are instead seen as the “add on”, then we might see a whole shift in the marketplace.
I dunno, it just seems dumb to have all these duplicate silos. And so many questionable non-OEM batteries out there too. Some market consolidation seems like an opportunity.
Every major company that makes power tools would want *their* battery design to be the standard for what all other companies would use, because of patents and licensing.
You aren’t going to get the tool companies to cooperate and work together on on single battery design to rule them all and share the profits equally, and that’s probably a good thing.
If the tool companies did do something like that, I’m pretty sure it’d turn out the opposite of what you’re thinking of. They might as well just all agree on standardized pricing for their batteries, also known as price fixing.
You *want* competition so one company can offer the batteries at a lower profit margin and attract customers who are sick of buying overpriced batteries, and then companies have to find the balance between making a profit and losing customers.
I dunno, Metabo has a lot of brands lined up for the one battery platform in Europe. If it works there, the only reason it wouldn’t here is being stupid.
It’s still in its infancy, but will be interesting to see how it goes and how many other brands join up over there.
That’s apples to oranges. It’s not like Dewalt, Milwaukee, and Makita sharing a battery platform. It’s more like Dewalt licensing their batteries to Graco. Most of the other companies in the Alliance make one or two cordless tools and don’t want to bother with the R&D and the patent issues (see previous article) that come with creating their own battery system.
It wouldn’t shock me to see the European Union mandate a common cordless tool battery form-factor. There are rumblings that they’re going to mandate a common charging porth for all cellphones so it doesn’t seem like much of a stretch for EU to turn its attention at some point towards the plethora of mutually-incompatible battery form-factors.
I think a lot of it has to do with locking people into a platform. If I have Makita batteries and I see a good deal on a Makita bare tool, I’m more likely to buy it.
I think the other potentially bigger issue is liability.
The batteries do not have the ability to shut themselves off like people think they do. The cells are wired directly to the terminals (with the exception of FlexVolt which has a mechanical switch for 20V, 60V, and separating the banks).
The only thing keeping people from smoking the tools or batteries is the communication between them. The batteries have anything between a thermistor and a micro processor that “talks” to the tool, and tells it not to draw current from the battery if there is too much heat or a fault condition (like low cell voltage). Some low draw tools like lights are able to get away with not having this communication, but the problem with this is that if you run the light until the battery is totally dead to many times you’ll degrade the cells.
This is also why you need to be very careful with battery adapters, they do not translate the communications between the brands, they simply allow you to pull as much current from the battery as you can.
Do you think Dewalt is going to trust a Ryobi tool to communicate properly with their battery? By locking down the tools and batteries, they are saving themselves from the potential liability.
Ron E G
You are incorrect sir. All Lithium Ion batteries are required to be fused to prevent too much current draw. This is to prevent them from going into thermal runaway which then results in fire. Most (if not all) of these fuses are the resettable type. Every lithium ion battery pack that is sold in a consumer type device also has a microcontroller in the battery pack to monitor/regulate it.
There are charging systems for LI component batteries that sample and test the capability of the battery and then charge them accordingly. I would assume for the costs of the batteries and the chargers that tool makes or atleast the big pro tool makes are using some of that tech in their chargers.
SO Dewalt but not necessarily Craftsman or Black and decker. Milwaukee and maybe ridgid but not necessarily Ryobi. etc etc.
So I don’t worry so much that charging my tools batteries as fast as the charger allows is hurting their capacity. I do agree however that full 100% capacity charging on most LI batteries is bad for them and more detrimental than stopping ar or around 80%, and currently no tool platform system does this today. I would like to see a system that let me set the charge depth of my tool batteries but when a 18V-4AH battery costs less than the replacement for my cell phone. I have to say it’s not a top worry.
This is certainly what I normally do with my Li-ion powered car.
And it’s certainly one car manufacturer’s recommendation I’m okay with.
Though I deliberately override the concept sometimes. Partly because I have a (personal?) Level 2 charger where I usually park it.
Bosch has the best batteries and 6 year warranty on it. No other company has a better battery technology. I’ll stick to my Bosch tools, never had any issues.
Yes any fast charging to where there is heat build up WILL shorten the life span. And just fast charging will shorten the lifespan of the battery. When I use the rapid charger everything gets really hot and its not good for the life of the battery. Faster is not always good.
Has anyone else experienced problems with the RedLithium USB batteries?
I have several and they have all died (strobe red & green) unable to charge.
Most of the guys at my work have had this issue as well.
We all jumped on the rechargeable headlamps when they came out, but are slowly switching back to other brands, because the Milwaukee USB batteries haven’t held up.
While I haven’t had any die and refuse to charge, I have gotten what seems like short run times from all of my 4v Red Lithium lights. Some have discharged completely while sitting unused.
While I’ve never owned or used the little Milwaukee USB charges batteries I wonder if their charger might not be as sophisticated as the 12 and 18V versions regards protecting them from overcharging?
Plus the cells are likely very different as is their “container”?
I’ve had this happen several times with the redlithium USB and found if I take them out of the holder for a few seconds and pop them back in they seem to work like normal.
I’m not saying it’s acceptable, but at least in my case there’s been an easy fix.
From everything that I remember from when I used to be into rc helicopters a faster charge rate is always going to do more damage than a slower one. Of course the difference a single cycle makes to a battery is so small that in then end the difference between the two charge rates might not make that much of a difference compared to the overall age of the batteries.
For rc helicopters the common rate of charge for batteries is 1 C which is one amp per amp hour of the battery, so so if discharged all the ways to 0% capacity (which you never do) it would take 1 hour to charge your battery. Since you never really discharge a lithium battery below 20% capacity, the actual charge time is around 45 to 50 minutes.
Even with the small packs the super charge won’t really charge them in less than 30 minutes, which would be around a 2 C charge rate, which is normally the upper limit that the rc helicopter people would charge at when they are in a rush, because anything above that is viewed as doing more damage to the battery than is worth it to them.
So while fast charging the smaller packs probably does do some damage to them its not enough to be noticeable except for maybe after a bunch of charge cycles which you would still loose some capacity with the standard charger anyways. I don’t know what the exact numbers are for Milwaukee batteries, but lets say that its being used by a professional and they put 250 cycles on them over a year, lets say with the normal charger they’ll loose 5% of their capacity by the end of the year and 10% with the super charger. That still isn’t that much of a difference and while it would be noticeable if you had two packs to compare like that its small enough that if you don’t have a direct A/B comparison I don’t think it would be noticeable that the faster charging is damaging the batteries
Disclaimer: It’s been quite a few years since I’ve been involved with the rc helicopter community so that some of that information has changed. Also I doubt that Milwuakee is using the same battery chemistry as the rc ones are, and I don’t know exactly how that would change how the Milwaukee batteries behave
18650 cells come in a variety of charge and discharge rates..the current premium samsung cells are rated at 30c.
Older ones were rated at 20c and 25c and these can still be found in lesser capacity packs.
Sort of like ” binning” in the chip industry.
Metabo battery system is being used now by 10 different companies, mostly German. This is forward thinking.
This is the first I have heard this not owning any Metabo. Who else uses their batteries?
Mostly very small european companies with very narrow specialties.
But they look very similar to M18 batteries lol.
They are up to 17 now.
I myself have a hard time believing Samsung is building specific Milwaukee batteries or DeWalt specific etc…
The 21700 batteries being used in the packs now all look the same, same color and same numbers on them
They are not milwaukee or dewalt specific. Its the same cell as far as being the 4000 mah cell or the 3000 mah cell. Samsung is making them. The 21700 is 4000 or 3000 mah. And the 18650 is 3000 mah. The 21700 has a 40 amp discharge and the 18650 has a 30 amp discharge. Anyone can buy any of these cells thus they are not milwaukee or dewalt specific.
Samsung likely makes a cell that appeals to power tool applications (a balance between high discharge and mid-upper capacity.) But they’re not making cells specifically tuned for a particular manufacturer.
ex: Milwaukee 12.0/8.0 + Dewalt 12.0/8.0/4.0 + Metabo HPT 8.0 + Bosch 12.0/8.0/4.0 all use the exact same Samsung 40T 21700.
I believe Sony/Murata has a comparable 4.0 Ah 21700 as well. But I’m not aware of anyone who uses it. Maybe Makita XGT.
Furthermore the Milwaukee HO 3.0/6.0 and DeWalt 3.0/6.0XR/9.0all use the same Samsung 30T 21700.
The cell manufacturers arent making custom cells fkr each brand.
Each company is testing cells either individually or as random samples batch by batch and qualifying the batteries for use.
Its “binning”..the same as in chip manufacturing and certification.
If a Pentium II failed at 500mhz they would test it at 400 and then 300.. Until they found what speed it ran stablely and with the correct results ( mathmatically).
Great article! I believe you too since no way Milwaukee would offer a three year guarantee on their batteries if their own systems were ruining them. Pay more now for Milwaukee but it lasts forever.
Well, sure. Batteries designed for faster charging in a Super Charger probably won’t degrade much if any more at their maximum charge rate than a battery designed for a Rapid Charger would at their maximum charge rate.
All things being equal, though, the faster you charge a battery and the faster you drain it and repeat those fast charge/discharge cycles, the shorter the battery life compared to a battery that only sees light use and slow charging.
The thing is though, the purpose of the batteries isn’t to stick around for decades. They’re designed to be able to deliver that juice to the electric motors in the power tools and move the bits and blades that get the work done.
Really, it’s quite impressive how far batteries in cordless tools have come, where you now have high-capacity Li-ion packs that can deliver more than enough power to get the job done, often with advantages in size and weight over corded tools.
I have mostly milwaukee tools and they are simply the best when it comes to warranty going by date of manufacture, no receipt needed The fuel line is awesome .the tool line extensive and just about indestructible and they have some 120/12 volt input car chargers that will charge18 volt packs thus giving you superb charging options.
0f course you can’t go wrong with the Ridgid line for the lifetime SA, just remember to register . that’s where Ridgid makes MONEY people forget to register like i have so no warranty. READ THE FINE PRINT!
I had charged a Milwaukee 9 amp hr battery on their rapid charger, it killed the battery. Now only has 1/3 capacity . I blame the rapid charger. The battery was fairly new. Normally I only use reg chargers and the six pack charger. I will never use the rapid one again.
If it was fairly new, it might be defective. The types of longevity concerns we’re talking about wouldn’t/shouldn’t be observable in fairly new batteries.
Regarding whether charging rates affect cordless power tool batteries: I was pleasantly surprised when researching the topic of reviving dead batteries on YouTube & elsewhere. After watching a half dozen or more videos and reading the comments sections, one thing became glaringly apparent: Almost all major brand batteries have built in obsolescence. A common practice among many manufacturers that produce rechargeable battery devices. It occurs when the batteries where run too low after so many charges with frequent use. Truth is, all these allegedly dead batteries can in fact be revived by using simple battery to battery jumps using common electrical wires. The procedure is simple and works. Now ask yourselves why all these major manufacturers make chargers that won’t recharge batteries that measure below the threshold they set in their rechargers?
I did my own experiment by taking a few batteries from the disposal bins at my local Lowe’s. Every single one when jump wired to another fully charged battery and then put into their chargers went on to take a full charge and worked just fine.
And BTW, the largest number of allegedly dead batteries were DeWalt. I found much fewer Milwaukee, Makita or Bosch batteries, but likely since Lowe’s only sells certain Bosch cordless tools.
What all this research shows me is that the chargers have a False threshold at which the user thinks the battery is dead forever. Truth is, they are not. But many get forced to buy new batteries. Guess who benefits by this false obsolete signal? That’s right, all the major brands. It’s not hard to see through this scheme to sell more batteries, especially when you see sales where the cost of the replacement batteries equals or exceeds the bare tool only prices.
I would urge my fellow tradesmen here to check out these YouTube videos yourselves and read all the positive comments posted under each video.
Bottom line? The false recharging thresholds are set in the chargers and not the batteries themselves. Otherwise, how could I have recharged so many supposedly dead worthless batteries and had them work and recharge just fine many times over? Answer: It’s rigged obsolescence when the batteries simply have too low of remnant charge that the chargers refuse to recharge them.
Just research under search terms “reviving dead cordless drill batteries”. Last time I checked, there were over a dozen YT videos all showing the exact same jump techniques and the exact same positive results. The game is always rigged at some point, no matter who the manufacturer is.
I was only wondering about rapid chargers effects on battery life the other day. Thanks for your article.
My dream Milwaukee accessory would be a narrow trench digging add on to put on the chainsaw instead of the bar.
Everything you would want to know about batteries. No matter what a manufacturer says they wont get away from the physics of batteries and battery charging. If you want specific degradation rates of Milwaukee batteries you will have to test that yourself but the principals are still the same.
The discussion here is not about theory but about measurable effects. Lift your foot and then stop down on the ground. You’re applying force to the Earth, but does this mean you’re going to throw the planet off its axis? Of course not. If you don’t like that analogy, consider gravitational force. In theory, you have a gravitational pull. In reality, objects aren’t going to start orbiting you.
If Milwaukee says their faster chargers won’t negatively impact the life of their batteries, you can certainly doubt it and argue against it, but right now, there’s no contradictory empirical proof, nor has there been any trend of user complaints that I’ve received, seen, or heard about.
If you go to the link you will see the data that the website offers. Tests were done and empirical data was measured and recorded. I’m pretty sure I remember seeing data on lithium batteries and since lithium batteries haven’t really changed too much since then we should be able to apply that data to lithium powertool batteries with reasonable enough accuracy.
You can extend conclusions about tested Li-ion cells to form a hypothesis about M18 Li-ion battery packs.
When talking about unrelated testing, you can certainly make assumptions about M18 Li-ion battery tech, but you can’t say those assumptions completely invalidate Milwaukee’s claims and statement of facts.
You have extended generalizations or assumptions on one side, and marketing claims on the other.
If we start off with the scale balanced, my stance is that we need user data and information or battery pack (not cell) testing to seek out independent truth. Testing would very time consuming or very pricey. If there was an issue with battery pack longevity, I would/should have heard about it by now. Users complain when there are patterned failures, and the lack of such complaints could mean the absence of issues.
For Milwaukee to say that their faster charging rates don’t negatively affect battery longevity, such claims are usually legally-backed. In this case, the information was provided via email and not in their advertising, and so it might not be, but I’m still very confident they did the necessary testing to back up the claims they are making.
Milwaukee absolutely has the means and internal motivations to know how their battery packs can be pushed.
So when it comes to generalizations vs. what are presented as facts, I’m inclined to give Milwaukee’s claim of negative impact greater weight.
I had been skeptical in the past, regarding their 9Ah batteries, but testing proved their claims. On paper, 3x 3.0Ah cells shouldn’t out-perform 2x 2.5Ah cells, but in practice the 9Ah battery packs did best XC batteries. The XC batteries over-temped but the 9Ah batteries didn’t, where on-paper there shouldn’t have been much of a difference for the cells.
The statements “This [super] charger does not have a negative impact on battery life.” and “No, there won’t be a difference in lifespan of batteries between standard, rapid, and super charger.” are ABSOLUTELY FALSE.
Faster charge rates increases heat in cells. Increased heat means decreased life. This is the laws of physics, people. There’s no free lunch.
If they were to insert the word “significant” or “noticeable” into those statements they might be true, but to outright state that faster charging has zero impact on battery life is 100% pure Grade-A B.S.
This is Milwaukee marketing at its finest. They want you to believe their “Red Lithium” batteries are different and better than everyone else’s. They’re not. They use the same commodity cells as everyone else. Charge any Lithium Ion battery faster and it will live a shorter life.
Actively cooling the battery while charging is THE ONLY WAY to charge a battery faster without degrading its performance. Makita has been doing this since 2005, and others have started (like Ego for example).
Stuart, Milwaukee might give you a fancy tour of their labs but I guarantee they’ll never show you the data they collect as a result of these tests. Why? Because even if the batteries showed 1% more degradation from Rapid Charging their statements above would be considered lies. They are lies, BTW, as no company has ever designed a battery that’s not negatively affected by higher charge rates.
Milwaukee used commodity cells, they don’t make their own, so they’re bound by the same rules as everyone else. I would even go as far as to say, the main reason they have such an impressive looking battery lab is so they can show off an impressive looking battery lab. With influencers impressed, all that extra marketing and customer confidence that comes from advertisements like this surely pays for all that flashy looking equipment.
Joseph Galli is no idiot; he knows how to market things, and Milwaukee’s NPS media gatherings are proof of this.
Stuart should ask Milwaukee for an all expense paid visit to their factory in the People’s Republic of China. Then he can give us verification that their tools are in fact “professionally made” in the PRC as is stated in the super small fine print on all the labels on their tools that bear the model & serial numbers.
The express implication of this claim is that all their Chinese workers are in fact very highly trained and skilled assembly line workers, and presumptively paid professional level wages.
Ironically, none of their batteries also state this claim, but also do NOT say Made in USA. Hmm
The reason I pose this question is that I’ve bought some of their XC 5.0 batteries which were dead out of the package, i.e. they would not take a charge at all. I had to return them to HDepot for new replacements.
I wonder how many others who frequent this blog have also experienced this same problem. If you have, please post a reply.
And BTW. TECHTRONIC Industries, a Chinese corporation, bought out Milwaukee in 2004, 15 years ago. I can’t figure out why so many tradesmen still think Milwaukee is an American owned company just because they still have operations & offices in Wisconsin. Go to www. ttigroup.com
Bosch uses 80/20 for their newer chargers. 80% fast and then the last 20% was they call long life mode. Is this type of thing what other manufacturer s are doing as well in their fast chargers? I have tons of batteries so I’m not to concerned about speed so I’ve been using the duel 12v/18v charger which charges slow and to my knowledge doesn’t use the 80/20. If I did need a battery charged faster I would just use the faster charger without worrying about it.
This is actually the nature of all but super advanced lithium-ion chargers (like Tesla super chargers). They charge at constant current until a voltage is reached, then constant voltage which makes the current progressively drop until it’s fully charged.
I do know newer Milwaukee chargers blink green when 80%, then solid when full. So you can pull them off early to be a little easier on the battery.
Bosch batteries are the best and have 6 year warranty!
Right on!! Can’t figure out why some tradesmen bash Bosch, other than the fact they are DeWalt cult followers. The warranty says it all. DeWalt batteries have consistent early failure rates, but DeWalt die hards never want to admit it. Ditto for other brands with wimpy warranties and poor customer service excuses for batteries and tools that die just AFTER the warranties expire. Come on, guys. Get wise to this game to get further into your wallets
Of course, charging at a higher rate degrades Li-Ion cells faster. Of course, Milwaukee will tell you it doesn’t.
The real answer is in the details. As mentioned, degradation is minimal in higher grade cells charged at higher rates. The question here is, how much “minimal” is acceptable? 10 cycles? 50 cycles? 75 cycles? Until we know that, I’m keeping my 4a and 3a chargers tucked away, using my 1.5a charger on all my DeWalt battery packs. If I need a honking big charger, perhaps I’m better off buying 1 more battery instead.
Is heat the enemy of cells, or is fast charging the real enemy, for which heat is just a symptom? I think both. Again, the real answer is in charge cycles. The answer is out there, it’s going to be hard to find.
If someone can tell me charging at a high rate only costs me 10-15 cycles over the life of a battery, I will feel fine using my higher rate chargers.
I agree that it’s good to have a balance – standard charger when time isn’t as important, and rapid in the field.
I tend to over-use the 6 port M12/M18 charger because of its 3 simultaneous ports and single plug, but if I only have one battery to charge and it’s not a high capacity HO charger I go with the first standard charger I find.
If there was evidence that fast charging impacts battery longevity do you think we would every hear about that?
., companies WANT to see highly profitable batteries. People are impatient and don’t want to wait if at all possible.
With the exception of Ridgid which offers lifetime warranty on their batteries companies have no advantage to be honest about this.
Can confirm for Milwaukee rapid charge at least that the charger charges above the actual cells fast charge rate, 4.5a on their 12v gear. Samsung 30q and LG hg2 are only rated at 4a fast charge. 100% would not buy.