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davekro

macrumors regular
Original poster
Mar 31, 2011
171
53
No. Calif.
The question I have is that during my work day using the laptop, and just now deciding to keep it plugged in all day, then unplug it and put it to sleep for the night, does it make any difference at all if I use my Apple 67W charger for this, or would a slower, lower watt charger be healthier as a "work day charger"? Could I get by using one of our 10W iPad chargers as a "work day charger"? I wonder if that would keep up, with my Excel, Outlook (and goof off web surfing) during a day. I am self-employed and work from home mostly. When I stop running my MBA on just one external monitor and add in the second monitor connected to my previous desktop Mac Mini, I will be getting a docking station Dell 6000 or similar. The Dell 6000 dock says it has 65W using USB-C. I guess 65 watts would be my "day charge" rate down the road...

How can I see how many watts I am currently using or on average during the day? Google was no help. Activity Monitor shows all kinds of "processes" options, none of which, that I can tell, show simply current wattage draw of the MBA. This and over time average watts use sure would be good to see. I guess I'll be springing for the iStat Menus 6 app ($12) sooner rather than later.

I opted for the 67W charger with my MBA M2 order. I know you are not supposed to leave the MBA on the charger full time (24/7). I mostly use my MBA M2 as my desktop computer at home. I am not sure how to manage the charging to not rack up charge, deplete, charge... cycles seemingly so quickly.

It may not be applicable to this newer technology, but I have it in my head that for example it is better, assuming time is not a factor obviously, to charge Li-ion devices slower as that is somewhat easier on the battery's health. I just watched a credible YouTube video that said it was good to leave your MBA (M1 in his case) plugged in while using it at work all day. I have been unplugging this new MBA M2 when it got to 100% and plugging back in when low. This method has me at 16 cycles in 23 days of use, so ≈ 0.7 cycles/ day. Besides the cycles seeming to rack up quickly, I often don't notice it at say between 10 or 20%, but much lower, which is not a good long term thing.


Thanks for any thoughts or links to educate myself on this topic.
 
I don't know what's better. What I do is I keep it plugged when it's at home all the time. It shouldn't be a problem because the battery is not working, so it's like if you were not using it (once it's full).

And actually I think this is better than just be filling up and emptying the battery all the time and wasting battery cycles.
 
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The question I have is that during my work day using the laptop, and just now deciding to keep it plugged in all day, then unplug it and put it to sleep for the night, does it make any difference at all if I use my Apple 67W charger for this, or would a slower, lower watt charger be healthier as a "work day charger"?

Thanks for any thoughts or links to educate myself on this topic.
Hi there.
The solution that I currently using is AlDente: https://apphousekitchen.com
I have configured it to stop charging at ~75%. That way I can use all day plugged
without damaging the battery.

I'm not sacrificing portability, so when I need to use it unplugged, I do.
In one month I have 7 cycles on the battery.

If you use AlDente, the wattage of the charger wouldn't matter as much. However if you need to unplug
the MBA often, charging of the battery back would happen at a higher speed. It's common belief that this is not
good for it (since faster charging also generates more heat).
 
"filling up and emptying the battery all the time and wasting battery cycles."
This is exactly what I want to avoid as much as possible. I'm trying to discern if keeping my MBA M2 plugged in through the work day to my current Apple 67W charger (or future Dell 6000 Dock 65W charge), has any negative effect on the battery or adds to battery cycles.

Today, the MBA has been plugged into the 67W charger for ≈ 6 hours or so up to now. It was at 23%, went to 100% where it has remained the whole time. It seems the 67W charger keeps battery topped off all day as I use VERY small amounts of power. How does this affect battery cycles? I really do not understand 'cycles' in this usage scenario. Is being plugged in all work day, unplugging from say 10pm to 9:00am 5 or so days a week, and unplugged days it is not in use the best way to extend my MBA's battery life? I plan to use this MBA M2 for hopefully ten years. My last MBA (mid 2013 13") was in part time use until I got the M2, so 9+ years. It was not my main machine. This M2 is taking over as my main machine from my late 2012 Mac Mini. (specs of current and retiring machines below).
 
Hi there.
The solution that I currently using is AlDente: https://apphousekitchen.com
I have configured it to stop charging at ~75%. That way I can use all day plugged
without damaging the battery.

I'm not sacrificing portability, so when I need to use it unplugged, I do.
In one month I have 7 cycles on the battery.

If you use AlDente, the wattage of the charger wouldn't matter as much. However if you need to unplug
the MBA often, charging of the battery back would happen at a higher speed. It's common belief that this is not
good for it (since faster charging also generates more heat).
I have a hard time figuring out these cycles. Ive plugged in my MacBook 5 times over 3 weeks now, always above 20% battery left and im somehow at 10 cycles
 
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Hi there.
The solution that I currently using is AlDente: https://apphousekitchen.com
I have configured it to stop charging at ~75%. That way I can use all day plugged
without damaging the battery.

I'm not sacrificing portability, so when I need to use it unplugged, I do.
In one month I have 7 cycles on the battery.

If you use AlDente, the wattage of the charger wouldn't matter as much. However if you need to unplug
the MBA often, charging of the battery back would happen at a higher speed. It's common belief that this is not
good for it (since faster charging also generates more heat).
I just downloaded the iStat Menus 6.62 14 day free trial. Does anyone know if this app has any capability to limit charge percentage (and maybe charge rate too?) as the AlDente APP that diego.caraballo is using?

Long term, I will need to get a docking station that allows two monitors to be used on my M2. Now I can see that if I can find one that has adjustable charging features similar to diego's AlDente, that would be extremely preferable to just another 65w charger. Also, once I can determine how to have iStat Menus tell me my current wattage use, then I'm thinking I could find an all day while working charger that charges close to my average use rate. I don't have the battery tech knowledge if even that strategy is a good one though. Hopefully, some here may have some ideas on this "charge rate during work day process" might best be handled. I do tend to overthink many things, so some perspective on the bell curve from best possible batt. health plan, middle of the road plan, worst long term battery health scenario, would be very helpful. :) If I can adopt a plan that is at least in the 65% to 80% of the Best long term battery health plan. I would be happy.
Having no clue is the worst case scenario for this OCD person. ;)
 
I also use the free version of AlDente, and I like it so far (about 2 months of use on new 14" MBP).

Keep in mind that most Li-Ion batteries have the best lifespan when not charged to 100% all the time, nor run down to 0% frequently. A good overall guide: Charge to 80%, discharge to 20%.

AlDente helps with the charging to 80% (or less) bit, which is the hardest to manage manually.

Does it help with cycle count? I have not tried to figure that out.

Battery info, for this machine running probably an average of plugged in about: once per day, 6 days a week, for about 100 days (but AlDente only on for about 60 days):

Battery Information:

Model Information:

Firmware Version: 0b00
Hardware Revision: 100
Cell Revision: 4814
Charge Information:
The battery’s charge is below the critical level: No
Fully Charged: No
Charging: No
State of Charge (%): 77
Health Information:
Cycle Count: 32
Condition: Normal
Maximum Capacity: 97%

System Power Settings:

AC Power:
System Sleep Timer (Minutes): 1
Disk Sleep Timer (Minutes): 10
Display Sleep Timer (Minutes): 30
Sleep on Power Button: Yes
Wake on LAN: Yes
Current Power Source: Yes
Hibernate Mode: 3
LowPowerMode: 0
PrioritizeNetworkReachabilityOverSleep: 0
Battery Power:
System Sleep Timer (Minutes): 1
Disk Sleep Timer (Minutes): 10
Display Sleep Timer (Minutes): 30
Sleep on Power Button: Yes
Hibernate Mode: 3
LowPowerMode: 0
 
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Hi there.
The solution that I currently using is AlDente: https://apphousekitchen.com
I have configured it to stop charging at ~75%. That way I can use all day plugged
without damaging the battery.
Diego,
Are you using the free or one of the Pro versions of the AlDente App? Doess the free version do all you need, or does the Pro version have significant pluses that you feel are worth the Pro subscription? ($9.69 Annual subscription, or $20.39 Lifetime subscription). Thanks
 
I have a hard time figuring out these cycles. Ive plugged in my MacBook 5 times over 3 weeks now, always above 20% battery left and im somehow at 10 cycles
This Apple Support page explains what battery cycle is: Why Lithium-Ion?

There is more to battery health than the number of cycles. Age of the battery matters and also how long the charge is held at above 80% or below 20%. Optimized battery charging can help with keeping your battery in a safe range until you need it. You can’t do much about the age of the battery—try not to overheat it since that will age it prematurely.
 
Battery cycles is only part of the picture. I've purchased MacBooks with low battery cycles (less than 100) that could barely hold a charge.

macOS manages battery health now. My 14-inch Pro hangs out around 80% all day. When I bring my Mac out into the wild, it'll charge back to 100% but after a few days it'll stop charging at 80% again.

For 99% of people there's no need to manage battery charging with 3rd party apps or have to worry about leaving your Mac plugged in anymore. Just unplug it once and awhile and get some fresh air or something.
 
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To answer OP's question: you can find out average watts with this tool:

My MBP rarely peaks above 15W unless I'm doing exports in FCPX. In fact my Mac will happily stay charged with an 18W charger. The 96W charger that came with my computer is overkill.
 
Diego,
Are you using the free or one of the Pro versions of the AlDente App? Doess the free version do all you need, or does the Pro version have significant pluses that you feel are worth the Pro subscription? ($9.69 Annual subscription, or $20.39 Lifetime subscription). Thanks
I use the Pro, lifetime version. The plus is to use the sailing mode and the temperature protection.
I also removed the Mac battery indicator and use the AlDente icon only (icon + percentage). To have a custom icon is a Pro feature as well.

But you can totally test the app before and decide if it’s working for you.
 
Love Aldente. I have total control and don't have to worry about Mac crappy algo charging to 100% every time the stupid cord gets disconnected.
 
OK, I just found out where my just installed iStat Menus app shows the "Total Power" usage. With the battery showing charged at 100%, looking at the last hour graph, 90% of the time it's using ≈ 7.4 watts, maybe eight spikes to 8.5W, two to 10W, and one to 12W. It looks like a 10W charger would maintain the battery and very slowly raise the charge percentage over a day of working with it plugged in.

I'll need to get an adapter from male USB-A to female USB-C so I can use one of our 10W iPad chargers (Output flat 5.1V at 2.1A). The 67W Apple charger that came w/ my M2 has 4 different outputs ranging from 5.2V/ 3.0A, up to 20.3V/3.3A. I wouldn't think using an older Apple iPad 10W charger as an "All Work Day" charger would cause any issues, but I am far from an electrical engineer. ;)

If anyone thinks any scenario of using a 10W, 5.1V, 2.1A charger as:
1) an "All Day while work" charger or
2) Overnight (or over a longer period as required) to raise the battery from say 20% from being out in the field, back up to 80%-ish, please let me know.

Am I correct in assuming correctly that keeping plugged in to essentially a trickle charge level that maintains the battery at a status quo charge level is a good strategy to reduce battery cycles? Obviously, this would heat the battery less than the 67W fast charge might do, not to drastic long term battery health, but not as gentle on the battery as a more steady lower wattage charge.

This would lower the battery's heat exposure over 10 years. Time's effect will be what it is. As long as the MBA is not used or stored in high ambient temperature environments, might this strategy be more optimal than using the 67W charger? I definitely will get the AlDente App and limit the charge % to say 75%, as Diego does.

Are there any apps that will give a settable low battery at "X%" banner notification, when battery reaches your chosen low limit? The Apple OS banner that pops out on my 2013 MBA at 5% was terrible. It just meant you had to turn it off before it was about to shut down anyway. The M2 gave me a banner warning at 10%. After I dropped the screen brightness as low as possible, seeing the warning, I was amazed at how long the battery lasted from there! Well, compared to my 9-year-old MBA from 10%. :p I need an app, as I am terrible about watching the battery level in the menu, especially if I am watching movies while away from power.

I am well past TLDR, but if you got here, thanks for hanging in. 🤙
 
To answer OP's question: you can find out average watts with this tool:

My MBP rarely peaks above 15W unless I'm doing exports in FCPX. In fact my Mac will happily stay charged with an 18W charger. The 96W charger that came with my computer is overkill.
That tool uses the powermetrics command line tool. It only shows the SoC package power. That doesn’t include things like the display or anything plugged in to theUSB-C ports.
 
I got confused about what USB-c to USB-a adapter would work to charge my MBA M2. So I decided to just buy a couple of highly rated Anker USB C Charger 20W, 511 Charger ( Nano ), PIQ 3.0 Durable Compact Fast Chargers $13.99. Look good w/ 4.8 stars and 79,363 ratings.
I also got the AlDente App and set it to 75%. Hey, my MBA is now at 54%. Crud, second time I have plugged the Magsafe3 cable into the 65W Apple charger.... but not all the way until it clicked. DOH!
Well now I will get to see it charge up to 75% and stop. :cool: Then I will unplug it and put it to sleep for the night. I'll report back with the charge rate on the new 20W Anker USB c chargers later this week.
 
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I’ve read somewhere that no matter what the wattage of a USB-A charger, the MBA will only charge at 5W max. To go higher than that, it needs USB-C PD to better determine what wattage to use. Guess there are smarter electronics involved with PD.

I tried this myself and connected a 1500mA (7,5W) USB-A phone charger. The MBA only charged at 5W.

EDIT: No, wait. I tried again with two other different USB-A chargers. One 10W (2A) iPad charger and one generic 12W (2.4A) charger. Both charged the MBA at 8 watts.
 
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I’ve read somewhere that no matter what the wattage of a USB-A charger, the MBA will only charge at 5W max. To go higher than that, it needs USB-C PD to better determine what wattage to use. Guess there are smarter electronics involved with PD.

I tried this myself and connected a 1500mA (7,5W) USB-A phone charger. The MBA only charged at 5W.

EDIT: No, wait. I tried again with two other different USB-A chargers. One 10W (2A) iPad charger and one generic 12W (2.4A) charger. Both charged the MBA at 8 watts.

Would an older tech non-smart charging, non-PD charger be better to get my desired result of charging at a lower rate (like closer to≈7.5W in my case) instead of a given charger max rated wattage?
Do PD smart chargers just have the tech to allow not throttling from the charger's higher volt/ amp capacities, as well as to allow limit charge rates as a battery approaches full SoC and drop to trickle at 100%.
But a few questions:
1) Would the MBA M2's software already do the similar thing, even when charging with a puny 20W spec charger?
2) Do older non-PD chargers already have the tech of reducing their watt output as the attached device's battery is approaching 100% SOC and PD just allows 'Fast Charge' (basically by not throttling from the charger's higher volt/ amp capacities)?
3) Would using such an under spec (20W) charger on a relatively very large capacity MBA M2 battery, just make an old or PD charger always out put its capacity ≈20W, but still reduce output as 100% SoC approaches?
4) For my desired rusult of very slow charging, it would seem I want to avoid a PD fast charger, but is there tech in these devices that still make them a better choice for my MBA M2, even thogh the MBA has its own charging safety software?

Don, since my MBA M2 seems to use ≈ 7.5 watts (per iStatMenu app installed yesterday afternoon) when being used working on Excel spreadsheets, I'd love it if my MBA/ charger combination throttled to charge a very low wattage!

The Anker USB C 20W, 511 Charger ( Nano ), PIQ 3.0 Compact Fast Charger that I ordered last night is PIQ.
The difference between the PD in a number of Anker chargers and their new powerIQ 3.0? "USB Power Delivery (USB PD) is an open fast charging standard. Developed and maintained by the same group that supports USB-C. Anker’s PowerIQ 3.0 is a proprietary fast charging standard that combines USB PD and PowerIQ 2.0 into a single USB-C port."
 

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"I tried this myself and connected a 1500mA (7,5W) USB-A phone charger. The MBA only charged at 5W.
EDIT: No, wait. I tried again with two other different USB-A chargers. One 10W (2A) iPad charger and one generic 12W (2.4A) charger. Both charged the MBA at 8 watts."
Don,
I am hoping you needed to use a female USB-c to male USB-a adapter to test your iPad charger to charge your MacBook Air. If so, what brand and specific adapter did you use (link would be very helpful)? Last night I wanted to initially buy one of these adapters, but some reading led to confusion if between which USB spec (USB 3.0 vs 3.1, or even 2.0) would work or not work for this charging scenario. I gave up researching when I could not find any definitive answers. So, if you have one that works... I want that specific one! :)

What MBA year, model did you test on?

:apple: A recommendation to anyone on any forum that you frequent: It is very helpful to always create a signature with info on what computer year, model, specs that you have (ex. 15 years of MBA's). That way, people reading your posts automatically know the context to which your comments may relate. Some even list prior machines they have had. Though maybe not relevant to a current discussion, it can give a reader a sense of that person's Mac experience level.
**(To create a signature: Click on your name in the upper right corner of the site and select 'Signature' from the drop-down, fill in your computer info and specs, Save.)

I have been active from time to time on a few automotive forums. Without knowing say what era of Bronco, year, full size or II, or Mustang, as well as the variation of specs like engine, auto. trans., convertible, etc, a reader may have little context to understand the relevance (to them) of a commenter's post. It is even worse, when the original poster does not supply info that gives context to their post. Many readers appreciate knowing your frame of reference. :)
 
Curious. My iPhone charging cube gets very warm when the phone is being charged from a depleted state. At 90% charge the cube becomes cool as the phone continues to 100% charge. Leaving the phone plugged in all the time it stays at 100% and the cube is cool to the touch. Phone is always cool while battery is on charge. Leads me to believe the microchip on the battery adjust the voltage according to the charge level. After 90% it keeps the charge in a trickle state.
Wondering if m2 mba wall cubes get very warm during charging yet get cool after 90% charge and remain cool if left plugged in at 100% charge.
 
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Honestly, using such a low power charger might actually do more harm than good in terms of battery cycle counts. If you have a 10W charger and the computer needs to pull 15W (even instantaneously, for a split second), it's going to pull that extra power from the battery. Even if you're using a tool such as Aldente to limit charging percentages, it's going to have to replenish that power back into the battery. This adds to cycle counts and uses the battery more.

Cycle counts themselves also aren't really a measure of the total wear of the battery. They are just a number. My old 2012 MacBook pro has over 1,860 cycles on the original battery and it's still at 87% battery health. Lithium Ion batteries love partial charges, especially in the range of 20% to 80%, so charges in that range do much less damage to the battery than states of charge that are outside of this range. Using such a low power charger is likely going to result in a lot of these tiny little partial charges, which won't do a ton of harm to your battery in those ranges, but it will still increase cycle counts over time and will likely still negate any benefits you get from using such as slow charger.

The best thing you can do for your battery health is honestly just to keep it in a healthy 20-80% range as much as possible. This is where the most benefits are in terms of protecting battery longevity. Tools like Aldente are great for this.
 
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Definitely something off with these cycle counts, I haven't plugged my MacBook in since Saturday and yesterday I was at 10 cycle counts, today im now at 11. Why are my cycle counts going up without ever plugging this thing in? Its been plugged in a total of 5 times, always above 20% charge and most the time unplugging around 80%.
 
Definitely something off with these cycle counts, I haven't plugged my MacBook in since Saturday and yesterday I was at 10 cycle counts, today im now at 11. Why are my cycle counts going up without ever plugging this thing in? Its been plugged in a total of 5 times, always above 20% charge and most the time unplugging around 80%.
Cycle counts are incremented on discharge. Lots of little partial charges will still add up and increment the total count (10 partial charges at 10% each = 1 cycle).

These partial charges are actually far better for the battery than full 0% to 100% charges are. Cycle counts themselves aren't really any direct indication of the state of the battery, plenty of batteries go well beyond 1000 cycles and still have well over 80% of their health left.
 
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Cycle counts are incremented on discharge. Lots of little partial charges will still add up and increment the total count (10 partial charges at 10% each = 1 cycle).

These partial charges are actually far better for the battery than full 0% to 100% charges are. Cycle counts themselves aren't really any direct indication of the state of the battery, plenty of batteries go well beyond 1000 cycles and still have well over 80% of their health left.
but ive only charged it 5 times and im at 11 now
 
but ive only charged it 5 times and im at 11 now
The battery probably had a few cycles on it from the factory during tests. If not, partial charges, even if you just put the charger on for a short period of time, will still increment those cycles over time.
 
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