I intentionally bought an older generation Milwaukee slow-chargwr. It charges both m18 and m12, and i use both. I have a fast charger, but I never use it. I am a diy guy who uses Milwaukee tools to fix stuff on my house and car. I used some of my Milwaukee tools when I built a deck on my house last year. When you charge batteries with a high current, you generate more heat, and it tends to decrease the life of the batteries. I just have a few batteries. When i am using a tool and a battery is low, i put it on my slow charger and use a fresh one. Generally i am not using one single tool for such a long stretch that i need to go through all my batteries in a day. Even my 6ah batteries charge in a few hours, and then i put them away and charge the next one over night. It works fine. I also use makita 18v tools. I prefer some Milwaukee tools and other makita tools. So when i was building my deck, I would use my makita circular saw and a Milwaukee impact. That means that I didn’t go through my Milwaukee batteries all at once. So i am generally charging both Milwaukee and makita spare batteries when i am doing a big project.
So for anyone who missed it or wants the shorter version. Standard charger 3amp charge rate. Rapid charger 6amp. Original super charger 13.5 amp and new super charger dual port is 18 amp.
My preference is to use a trickle charger on my automotive battery and for the same reason my preference is to use the standard charger on my battery powered tools. My .02 Btw, …. Thank you for a great channel and the information that you put out. 👊🏻
100%. At the very least, it can't hurt. All batteries like to charge slowly. Some like it more than others. Even if the difference in lifespan is minuscule, any battery will last longer the slower it's charged. So if there's no need to charge it quickly, don't. If we're talking about your job and waiting for a bettery will cost you money, of course charge more rapidly.
@@roots4x Total agreement with you, including all the points that you make. The one part that I don’t get is if you’re a professional technician my god you should have at least a battery for every tool, and in some cases like myself, I have a dedicated power strip with multiple chargers that allows me to easily cycle in battery charging time. I know times are tough but it should be part of your investment in your trade to have a back up battery which is very easily done if you have multiple tools and the same battery platform.
@@russellpottenger8584 I'm running under the assumption that the pro has a backup battery and that somehow they can burn through a battery in less than the time it takes to recharge another. I know it's easy with something like a circular saw or blower. For mechanics it might be more difficult to do.
You bring up a fair point. Because most of my tools are automotive related, they don’t have the same demands as a circular saw on a job site that’s running all day.
I just use the standard charger, I have so many battery's and I have no reason to charge anything fast if it's gonna sit on the charger all night anyway
So my thing is does Milwaukee make these super chargers to help the consumer or themselves. The reason I say this is because the faster you charge a battery and the hotter it gets basically affects the life of the battery compared to the chargers that charge batteries slower. So by doing this batterries could possibly have a decreased life which would cause a consumer to have to buy batteries more often.
The charge rate it can tolerate is based on the cell configuration, amount of cells, and chemistry. The high output batteries are capable of higher current flow in and out, and are meant to handle the higher currents. Older standard output batteries will only charge at their max charge speed no matter how much current the charger is capable of supplying. a standard output 6.0 will charge at fastest, 70 minutes on a rapid or super charger. The high output will charge at 65 and 35 minutes respectively despite the capacity being the same. Its due to the chemistry differences and what the batteries are meant to handle. As for longevity, charging Lithium ion batteries fully is the worst thing you can do to them for longevity. Ideally you'd want to keep them below 80%, but without that option being baked into the battery architecture, threre's nothing you can do about that. Charging from 80 to 100 is already slowed down anyways and the peak current drops like a brick
Part of the reason why they charge faster is because they have a cooling system that keeps the temperature down. it’s not like it’s just pushing more volts into the battery. the rapid chargers and superchargers on any platform do push more volts, but that’s mitigated by the cooling system in the superchargers case. if you were to put your battery on a regular charger in a controlled temperature and put a fan directly on it you would see faster charge times. With a regular rapid charger, you are risking reducing the amount of charge cycles. But most of us know that and for someone like me that is constantly cycling batteries at work the benefits outweigh the potential negatives. So I would say yes, they are making them for the consumers that use their products professionally.
I have the new 2 bay super charger I charged up a 6 and a 12 after draining them down they stayed in the 70s Temp the whole time never hit 80. Because the fans on that charger are legit. But yes heat will hurt your batterys. Also the fans stay on for a while after they are fully charged to keep them cool after charging.
I have the standard charger. 2 6a batts and one 5 a. I am going to grab at least 2 more milwaukee tools and one of those tools will have the 12v batt. I am fine with the standard with what I use them for. But great video anyways. I was a bit confused on the different chargers. Glad you made this video to clarify.
I just reasenty bought the new m18 1\2 router amazing tool. I got a second 6ah battery right away because it runs down fast. I bought the forge today. I've been waiting for your video on the new charger. Im thinking of getting a dual charger this will make it easier to pick one
Thank a million for such informative video, now finally I understand the difference between the milwaukee chargers. Nobody thinks about clarifying our mind, thanks again my friend and God bless you and your love ones.
@@Stefan_Van_pellicom is the other way around, the people that ask many questions are the ones that end up confused. The wise people don't ask many questions.
All rapid chargers do. There are things that can be done to minimize wear, and to be honest some battery chemistries and layouts can have minimal deterioration from rapid charging. So while it does make a difference, it might be such a small one that you'd barely notice. The slower the charge, the longer the lifespan. Charging strategy is dictated by balancing out lifespan and convenience. Charging a battery for 12 hours is usually untenable and would provide virtually no benefit over charging one at 2 hours. If you don't need rapid charging, there's no need to worry about it. Just don't do it. If you do need it for any reason, you should do it. If my profession relied on quickly charging batteries, I'd buy the fastest charger I could find. However, I'm a hobbyist and I've only needed a rapid charger maybe twice. The thing is, if you're using the batteries too quickly that a charger can't keep up with your rotation, you're likely heating up your batteries and it's very unhealthy to charge hot batteries. So it's a bit of a vicious cycle.
I bought three dual rapid chargers M18/M12 from eBay for $30 each. They arrived looking brand new since it's listed as an open box. I compare it to another brand new one from Home Depot, it matches everything even the weight of the charger. So I'm confident that it's legit. I say having three chargers is good enough for home DIY and small professional jobs. I want to get a Super Charger, but I learned that supercharging batteries will wear it down quickly. I don't need that unless I'm using a chainsaw and cutting trees daily and I want to have the next battery ready right away. Or just buy many batteries and have enough to last you a day.
Great content Super informative. Thanks for all the great videos. I'm a big fan of shop tool reviews. Thanks for all your hard work In making these. God bless
They should make a balancing cell charger ! It’s all well and good making batteries charge faster . But if you don’t have a Balanced battery what’s the point .
Thanks a lot. Very informative. They should consider several modes like: charge up to 80%, don't charge if percentage is bigger than 90%, etc. But the way it's interesting how much time battery could be plugged to charger so that it will not lose its efficiency Thanks
One to consider for those looking out there is the 6 port rapid packout charger. You can get a wall mount for it easy, and get a shelf or something for the other half. Much cleaner solution that you can take with you to the work site. Because we all know all the batteries die at once seemingly at the worst time. 6 M18 ports rapid charging enables you to make sure you have an open port as soon as one goes an you never have a charge queue.
Sounds like if you have the time to do so, the standard charger is king for long-term battery life cycles. But if you run them down rapidly, say for certain jobs/trades, the rapid and supercharger may be more necessary.
I have 3 rapid chargers for at home use. Only use 1, the other 2 are never plugged in. After 2 years, it started smoking and smelled funny when I was using it last week. I switched to a normal m18/m12 charger
What kind of rack do you use for hanging your tools, referring to that black mat hanging on the wall. plus where did you get the rack for hanging your milwaukee m12 drills
I have the fast chargers but I don’t use them because I noticed if I fast charge batteries they discharge fast and if I slow charge they discharge slow
On the 48-59-1802, it's actually 6A output PER SIDE, for a total of 12A output at 18V since it's a simultaneous charger. Same thing with the 48-59-1807, it's 6A per bank for 18A total output at 18V, or 4.5A at 12V for each of the 3 M12 bays.
Have the regular 18v charger which charges fine,but would not fully charge 8AH battery.I would need to remove and put back on to finish charging.I bought the rapid charger which charges fully but it is so loud with that transformer whine(?)I have to put it outside to use it.For the money iI spent on it just for 1 battery type makes me not very happy.
i have a auto repair shop have couple extra batteries and the charger that came with the kit i never run out of batteries the dead one always charges before my extra runs out. i don't think charging batteries real fast is a good idea don't really know
I like useing the slowest charger available because i belive if it gets charged slow it will discharge slow plus i think i will get more charge cycles, idk
Milwaukee product listings show charts saying these charters will charge batteries faster: Rapid charger: All batteries including M12 Super charger 6.0 HO and larger. New dual charger Super charger is not any faster, but shows 80% charged on chart.
@Shoptoolreviews. I am a big fan frequent user mechanic and farm owner of Milwaukee M18 and now M12 Fuel tools. Can you please answer me what the M in M18 and M12 mean? What does it stand for? Ans what happened to their older M28V and other battery platforms they use to have back in the day? I watch the channel and subscribe so I hope you have the answer.
Bosch power boost charger via bluetooth can be set to charge with power boost,max.lifetime (charge battery up to 80%) or conservation mode for storing battery.
The new supercharger charges my high output 8.0ah and 6.0ah older style batteries faster than any other Milwaukee charger i own..and of course it charges the forge fast af...
There has to be something very wrong with their ratings, otherwise it implies these chargers run at anywhere from 20 to 50% efficency which is horrendous. Ryobi's chargers are more like 80-90% efficient, which is weird because they're both TTI brands. That kind of efficiency loss can add up quick if you're using these every day. Just think of using these in the 175w inverter, and you're using all 175w. It takes 350-875w to charge the battery. You've increased your power usage by 2-5x. I truly hope these are some weird math error and these units draw a fraction of their rated power from the wall. Maybe make a follow up video testing the regular, rapid and super charger in how efficiently they charge a battery, and what kind of losses you see using each one. The rest are just variations and multi-port configs of the same chargers so not worth testing
Thank you for another excellent review! I have read that fast charging lithium ion batteries is not good in terms of battery life. Therefore I’ll stay with my old school/OG Milwaukee charger and wait a little longer for the battery to charge.
That's really not the case. Heat kills batteries, and also running them completely dead all the time hurts them as well. These new chargers safely analyze the data from each cell in the battery while it's charging, so it can safely charge them at a higher rate. Also, they will typically charge them really quick to 80-85%, then back off on the charging power for the last 15-20%. Thanks for watching.
Cant stand the fact that the super charger does not have a handle for christ sakes. Who wants to carry a charger with both hands!?!?!?!??!?!?!?! I mean seriously does noone walk into facility and think hey maybe we should put a handle on this........
Heat is the reason any electronic fails overtime. Faster charging has higher temperature than normal charging so rapid chargers do reduce the lifespan of the batteries compared to normal chargers. Rapid chargers for the job site when needed. Normal chargers at home to charge everything overnight is recommended.
Very impressive video. All killer, no filler. Thanks for making it easy for many of us to understand. I especially like the math portion.
I intentionally bought an older generation Milwaukee slow-chargwr. It charges both m18 and m12, and i use both. I have a fast charger, but I never use it. I am a diy guy who uses Milwaukee tools to fix stuff on my house and car. I used some of my Milwaukee tools when I built a deck on my house last year.
When you charge batteries with a high current, you generate more heat, and it tends to decrease the life of the batteries. I just have a few batteries. When i am using a tool and a battery is low, i put it on my slow charger and use a fresh one. Generally i am not using one single tool for such a long stretch that i need to go through all my batteries in a day. Even my 6ah batteries charge in a few hours, and then i put them away and charge the next one over night. It works fine.
I also use makita 18v tools. I prefer some Milwaukee tools and other makita tools. So when i was building my deck, I would use my makita circular saw and a Milwaukee impact. That means that I didn’t go through my Milwaukee batteries all at once. So i am generally charging both Milwaukee and makita spare batteries when i am doing a big project.
So for anyone who missed it or wants the shorter version. Standard charger 3amp charge rate. Rapid charger 6amp. Original super charger 13.5 amp and new super charger dual port is 18 amp.
Now THAT’s a summary ! 👍
That's all I really wanted to know 😂 I appreciate you
That 18A is shared so 6A simultaneous. It uses 12+6 when supercharging
Is the regular 3 amp (M12 and M18 combo) charger compatible with the XC batteries?
@@squatch545 yes the standard or regular just charges slower but it is compatible
My preference is to use a trickle charger on my automotive battery and for the same reason my preference is to use the standard charger on my battery powered tools.
My .02
Btw, …. Thank you for a great channel and the information that you put out. 👊🏻
100%. At the very least, it can't hurt. All batteries like to charge slowly. Some like it more than others. Even if the difference in lifespan is minuscule, any battery will last longer the slower it's charged. So if there's no need to charge it quickly, don't. If we're talking about your job and waiting for a bettery will cost you money, of course charge more rapidly.
@@roots4x
Total agreement with you, including all the points that you make.
The one part that I don’t get is if you’re a professional technician my god you should have at least a battery for every tool, and in some cases like myself, I have a dedicated power strip with multiple chargers that allows me to easily cycle in battery charging time. I know times are tough but it should be part of your investment in your trade to have a back up battery which is very easily done if you have multiple tools and the same battery platform.
@@russellpottenger8584 I'm running under the assumption that the pro has a backup battery and that somehow they can burn through a battery in less than the time it takes to recharge another. I know it's easy with something like a circular saw or blower. For mechanics it might be more difficult to do.
You bring up a fair point. Because most of my tools are automotive related, they don’t have the same demands as a circular saw on a job site that’s running all day.
I just use the standard charger, I have so many battery's and I have no reason to charge anything fast if it's gonna sit on the charger all night anyway
That's perfectly legit. You nailed it. Keep a backup battery and let the other charge. No need to spend extra money. Thanks for watching.
So my thing is does Milwaukee make these super chargers to help the consumer or themselves. The reason I say this is because the faster you charge a battery and the hotter it gets basically affects the life of the battery compared to the chargers that charge batteries slower. So by doing this batterries could possibly have a decreased life which would cause a consumer to have to buy batteries more often.
That’s why I charge with the standard charger.
The charge rate it can tolerate is based on the cell configuration, amount of cells, and chemistry. The high output batteries are capable of higher current flow in and out, and are meant to handle the higher currents. Older standard output batteries will only charge at their max charge speed no matter how much current the charger is capable of supplying. a standard output 6.0 will charge at fastest, 70 minutes on a rapid or super charger. The high output will charge at 65 and 35 minutes respectively despite the capacity being the same. Its due to the chemistry differences and what the batteries are meant to handle.
As for longevity, charging Lithium ion batteries fully is the worst thing you can do to them for longevity. Ideally you'd want to keep them below 80%, but without that option being baked into the battery architecture, threre's nothing you can do about that. Charging from 80 to 100 is already slowed down anyways and the peak current drops like a brick
Part of the reason why they charge faster is because they have a cooling system that keeps the temperature down. it’s not like it’s just pushing more volts into the battery. the rapid chargers and superchargers on any platform do push more volts, but that’s mitigated by the cooling system in the superchargers case. if you were to put your battery on a regular charger in a controlled temperature and put a fan directly on it you would see faster charge times. With a regular rapid charger, you are risking reducing the amount of charge cycles. But most of us know that and for someone like me that is constantly cycling batteries at work the benefits outweigh the potential negatives. So I would say yes, they are making them for the consumers that use their products professionally.
I have the new 2 bay super charger I charged up a 6 and a 12 after draining them down they stayed in the 70s Temp the whole time never hit 80. Because the fans on that charger are legit. But yes heat will hurt your batterys. Also the fans stay on for a while after they are fully charged to keep them cool after charging.
That's not how battery works. If you don't know, shut it
I have the standard charger. 2 6a batts and one 5 a. I am going to grab at least 2 more milwaukee tools and one of those tools will have the 12v batt. I am fine with the standard with what I use them for. But great video anyways. I was a bit confused on the different chargers. Glad you made this video to clarify.
I just reasenty bought the new m18 1\2 router amazing tool. I got a second 6ah battery right away because it runs down fast. I bought the forge today. I've been waiting for your video on the new charger. Im thinking of getting a dual charger this will make it easier to pick one
Thank you for covering all these chargers with an explanation of the differences. Very helpful.
Thank a million for such informative video, now finally I understand the difference between the milwaukee chargers. Nobody thinks about clarifying our mind, thanks again my friend and God bless you and your love ones.
As a religious person you probably don’t ask enough questions, that may be why your mind isn’t clarified. 😉
@@Stefan_Van_pellicom is the other way around, the people that ask many questions are the ones that end up confused. The wise people don't ask many questions.
@@Stefan_Van_pellicom The more questions you ask, the more confused you end up.
I charged a 12ah on the dual port super charger in 45min , 2 12ah in 1h15 , 1 forge in 20 min , i love the new supercharged its very quick
Do the Rapid Chargers put extra stress/wear on the Batteries ?
All rapid chargers do. There are things that can be done to minimize wear, and to be honest some battery chemistries and layouts can have minimal deterioration from rapid charging. So while it does make a difference, it might be such a small one that you'd barely notice. The slower the charge, the longer the lifespan. Charging strategy is dictated by balancing out lifespan and convenience. Charging a battery for 12 hours is usually untenable and would provide virtually no benefit over charging one at 2 hours.
If you don't need rapid charging, there's no need to worry about it. Just don't do it. If you do need it for any reason, you should do it. If my profession relied on quickly charging batteries, I'd buy the fastest charger I could find. However, I'm a hobbyist and I've only needed a rapid charger maybe twice. The thing is, if you're using the batteries too quickly that a charger can't keep up with your rotation, you're likely heating up your batteries and it's very unhealthy to charge hot batteries. So it's a bit of a vicious cycle.
Fantastic video! What chargers would you recommend for using 3 M12 tools simultaneously and having half a dozen m12 batteries on hand?
Never have been a fan of red tools but I sure can appreciate the math brakedown. Good job Tim. 👍
I bought three dual rapid chargers M18/M12 from eBay for $30 each. They arrived looking brand new since it's listed as an open box. I compare it to another brand new one from Home Depot, it matches everything even the weight of the charger. So I'm confident that it's legit. I say having three chargers is good enough for home DIY and small professional jobs.
I want to get a Super Charger, but I learned that supercharging batteries will wear it down quickly. I don't need that unless I'm using a chainsaw and cutting trees daily and I want to have the next battery ready right away. Or just buy many batteries and have enough to last you a day.
Great content
Super informative.
Thanks for all the great videos. I'm a big fan of shop tool reviews. Thanks for all your hard work In making these. God bless
They should make a balancing cell charger ! It’s all well and good making batteries charge faster . But if you don’t have a Balanced battery what’s the point .
Thanks a lot. Very informative. They should consider several modes like: charge up to 80%, don't charge if percentage is bigger than 90%, etc.
But the way it's interesting how much time battery could be plugged to charger so that it will not lose its efficiency
Thanks
I'm a Milwaukee guy and found this informative. Thanks.
Glad it was helpful! Thanks for watching.
One to consider for those looking out there is the 6 port rapid packout charger. You can get a wall mount for it easy, and get a shelf or something for the other half. Much cleaner solution that you can take with you to the work site. Because we all know all the batteries die at once seemingly at the worst time. 6 M18 ports rapid charging enables you to make sure you have an open port as soon as one goes an you never have a charge queue.
Thank you for this video. I did not know that there was a difference in their charger. Except the new forge battery platform.
Excellent breakdown! Helped me make the decisions I was trying to make. Much appreciated!
Sounds like if you have the time to do so, the standard charger is king for long-term battery life cycles. But if you run them down rapidly, say for certain jobs/trades, the rapid and supercharger may be more necessary.
I have 3 rapid chargers for at home use. Only use 1, the other 2 are never plugged in. After 2 years, it started smoking and smelled funny when I was using it last week. I switched to a normal m18/m12 charger
What kind of rack do you use for hanging your tools, referring to that black mat hanging on the wall. plus where did you get the rack for hanging your milwaukee m12 drills
I have the fast chargers but I don’t use them because I noticed if I fast charge batteries they discharge fast and if I slow charge they discharge slow
On the 48-59-1802, it's actually 6A output PER SIDE, for a total of 12A output at 18V since it's a simultaneous charger. Same thing with the 48-59-1807, it's 6A per bank for 18A total output at 18V, or 4.5A at 12V for each of the 3 M12 bays.
Thank you!
I have rapid charge and super charge for home use only, the rapid charge gets the job done I barely use my super charge
I have ryobi and use their regular chargers, the fast ones have no benefits and just wear the batteries out faster
Thanks for sharing!! Much needed info
Have the regular 18v charger which charges fine,but would not fully charge 8AH battery.I would need to remove and put back on to finish charging.I bought the rapid charger which charges fully but it is so loud with that transformer whine(?)I have to put it outside to use it.For the money iI spent on it just for 1 battery type makes me not very happy.
For the dual port rapid charger which is 6amp, when two batteries into the slot to charge, is it divide into two 3amp for each slot?
i have a auto repair shop have couple extra batteries and the charger that came with the kit i never run out of batteries the dead one always charges before my extra runs out. i don't think charging batteries real fast is a good idea don't really know
The "Milwaukee 48-59-1811 M12/M18 Super Charger $149:" is no longer listed on Acme Tools.
I like useing the slowest charger available because i belive if it gets charged slow it will discharge slow plus i think i will get more charge cycles, idk
Do you have a dc 12v charger
Milwaukee product listings show charts saying these charters will charge batteries faster:
Rapid charger: All batteries including M12
Super charger 6.0 HO and larger.
New dual charger Super charger is not any faster, but shows 80% charged on chart.
It charges to 80% and 15 minutes are you saying that that’s untrue? because it’s not I have one and it charges the forge battery to 80% in 15 minutes.
@18:40 diy needs more than one battery at a time. Saw, drill, mulitool, grinder, vac, blower......... ain't nobody got time to change or change.
@Shoptoolreviews. I am a big fan frequent user mechanic and farm owner of Milwaukee M18 and now M12 Fuel tools. Can you please answer me what the M in M18 and M12 mean? What does it stand for? Ans what happened to their older M28V and other battery platforms they use to have back in the day? I watch the channel and subscribe so I hope you have the answer.
😂 Milwaukee 12v Milwaukee 18v (m12) (m18) 😅
M28 is discontinued along with the old NiCad platforms
Bosch power boost charger via bluetooth can be set to charge with power boost,max.lifetime (charge battery up to 80%) or conservation mode for storing battery.
Something is off with that last set of specs. 4 amps in seams super low for that output.
Sweet, glad to watch your videos
Glad you like them!
The new supercharger charges my high output 8.0ah and 6.0ah older style batteries faster than any other Milwaukee charger i own..and of course it charges the forge fast af...
Thank you very much for the useful information bud
Another informative video! 👏
Big fail that the new charger doesn't accept m12 in my opinion. Id rather use the 6slot charger
Thank you for the information.
There has to be something very wrong with their ratings, otherwise it implies these chargers run at anywhere from 20 to 50% efficency which is horrendous. Ryobi's chargers are more like 80-90% efficient, which is weird because they're both TTI brands. That kind of efficiency loss can add up quick if you're using these every day. Just think of using these in the 175w inverter, and you're using all 175w. It takes 350-875w to charge the battery. You've increased your power usage by 2-5x. I truly hope these are some weird math error and these units draw a fraction of their rated power from the wall.
Maybe make a follow up video testing the regular, rapid and super charger in how efficiently they charge a battery, and what kind of losses you see using each one. The rest are just variations and multi-port configs of the same chargers so not worth testing
I’ll only use the regular chargers.
Thank you for another excellent review! I have read that fast charging lithium ion batteries is not good in terms of battery life. Therefore I’ll stay with my old school/OG Milwaukee charger and wait a little longer for the battery to charge.
That's really not the case. Heat kills batteries, and also running them completely dead all the time hurts them as well. These new chargers safely analyze the data from each cell in the battery while it's charging, so it can safely charge them at a higher rate. Also, they will typically charge them really quick to 80-85%, then back off on the charging power for the last 15-20%. Thanks for watching.
Rapid is all thats necessary, super is overkill.
Love your channel! I'm thinking of doing one for tools, but in Spanish
For the dual bay rapid charger of 6A, is it divide by 2 of 3A each slot when two batteries are charge at the same time?
LET'S GO TJ 🏁
I need Makita
Cant stand the fact that the super charger does not have a handle for christ sakes. Who wants to carry a charger with both hands!?!?!?!??!?!?!?! I mean seriously does noone walk into facility and think hey maybe we should put a handle on this........
14:37
Shocked there's no m12 ultra basic charger, I have one and I own zero Milwaukee tools.😬
👍🤘🤙
I've heard rapid chargers may reduce the overall lifespan of the battery. Has anyone else had that concern?
Heat is the reason any electronic fails overtime. Faster charging has higher temperature than normal charging so rapid chargers do reduce the lifespan of the batteries compared to normal chargers. Rapid chargers for the job site when needed. Normal chargers at home to charge everything overnight is recommended.
Flex tools have the best chargers
Too bad flex tools are trash
Best charger on the market is the Flex 4 port simultaneous charger.