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How to limit the maximum charge to 70%?
- Thread starter thulium
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Oh how I wish Apple would really warranty the battery for 3 years 1000 cycles without dropping almost $300 on the AppleCare extended warranty. Apple will only warranty your battery for 1 year here in the US. After that it's all on the owner.
By definition, the requirement was for the batteries to be at 50% SOC which would obviate any significant difference in the two cases. Further, I'm not sure where you would get the idea that "automatic" battery maintenance would be any better than leaving it alone. Let's look at what happens over the warranty period (1 year) under identical ambient conditions.
Case#1 - Battery initial condition is 50% SOC. Over the year, at an ambient of 20 Deg. C it will self-discharge to a lower state of charge - say 35%. This is almost ideal for maintaining battery capacity. The only way it could be better is if the ambient temperature was lower. At year end, the battery is capable of a very high proportion of its original capacity - say 97%.
Case#2 - Battery initial condition is 50% SOC and the battery management system is programmed to maintain this SOC. Over the year, with the computer turned on, it will operate on AC power exclusively until a drop in the SOC due to self-discharge exceeds a threshold of, say, 5%. So after perhaps a few weeks or month a charge cycle will initiated to bring it back to 50%. By the end of the year the battery will have gone through several of these very shallow charge cycles and at the end of the year the SOC of the battery will be between 45 and 50%. Again, this is very good for maintaining battery capacity. But it is NOT as good as Case #1 because inside the computer the battery is exposed to a higher temperature. The situation is as good as it can be though and the capacity at the end is still very good. 95% might be a reasonable guess.
No doubt!
If the BMS (battery management system) in the computer was removed and battery management was replaced by the average user, the battery problems would do more than skyrocket. I doubt the batteries would last one cycle!
If not removed, the BMS protects against almost anything bad that a user can do. The only exception is a user who discharges it down to 0% and leaves it unused. Then the battery will eventually be damaged by over discharge due to natural self-discharge.
It is a falsehood that Apple's BMS will be programmed to provide the maximum possible life. This wouldn't make any sense. It wouldn't be their design goal because it sacrifices too much run time on a charge. Rather, their design goal would be a compromise between battery life and discharge cycle run time. They would want to keep warranty claims and bad publicity to a manageable level whilst maximizing the run time they can put in their advertising literature. Therefore, a knowledgeable user can EASILY improve on the battery life. And doing this isn't rocket science. The easiest way to do this is to stop the charge cycle at a lower SOC - say 80%. But it is silly to ask a user to do this - there should be a settable option for the BMS to do this automatically!
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It depends on what you mean by "near-optimal battery treatment". If by this, you mean Apples design goals for the desired compromise between battery life and single discharge cycle capacity, then yes. If by this you mean maximum possible battery life alone, then no.
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You are right. Apple (or anyone else) can call 100% whatever cell termination voltage they want. 100% can be the normal 4.2V/cell. Or it can be 4.15 or 4.1 to prolong battery life. Depending on cell construction, it can even be as high as about 4.35V/cell to increase available discharge capacity. Along with reduced life, this comes with greater risk of catastrophic failure. But never lose sight of the penalty for reducing the SOC at charge termination - it is a huge blow to the marketing of the device due to the shorter run time!
An interesting data point here is an electric car. Here, a lithium ion battery must last through a much longer warranty period. What do they do? Well, they do several things, and guess what? One of them is to reduce the actual SOC at "full charge". In this case, sacrificing range (aka run time) is mandatory to avoid a warranty claim disaster.
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Since we are sharing anecdotes. I use my Mac portable very similar to you. Attached to an external monitor and running 24/7. Probably six or eight times a year I use it as a portable on battery for a trip.
I used a 2012 MacBook for two years like this with zero problems and good battery capacity when I sold it. Then I used a 2014 rMBP the same way for two years and it also had good battery capacity when I sold it a couple weeks ago.
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Battery bloat is not normal. That should be replaced under warranty.
Even if this would work, why would you want to do this? What are you trying to save the battery capacity for? Say you spend the next 2-3 years intentionally keeping the battery at 70% capacity? Say it managed to maintain 95% capacity. Are you going to suddenly use your computer to it's full capacity or are you going to continue to only allow yourself to have a 70% charge to keep it alive longer? You're basically artificially limiting the amount of usage you get out of it so, later on down the line, you might not have to deal with limitations. What's the point of that?
Battery bloat is expected if the battery has been used for some time in deteriorated state (that's why there is a service your battery warning). But I certainly agree that it shouldn't happen after 1.5-2 years...
what should or shouldnt happen is a matter of opinion. The fact is lithium batteries do not like to be sitting on full charge, plugged in all the time. And i dont like dealing with bloated batteries every 2.5-3 years, which has already happened to me twice in a row, on two separate macbook pros. So I would much like an app or way to prevent the battery from being charged, as an OPTION (for the new macbook pros with TB3 at least, since a workaround exists for magsafe MBPs) for people like myself. I hardly think i am being unreasonable. Those of you who are 'just fine' with the way things already work are more than welcome to keep doing what you do. But there is nothing wrong with some of us who want greater control, and I'm sure a decent number besides me would like this feature as well, hence the reason why this thread exists. And like I said before, if someone designs a hardware hack or app that does it, I will buy it
My macbook pro 2011 lived a similar life (between mid 2011 and early 2016) until it died of discrete GPU death (and i didn't bother getting it repaired).
Last i powered it up it had a battery health of about 90-91 percent (what's weird is i can still actually use it via remote desktop
)No battery swelling, etc. I live in a hot climate (Perth, Western Australia) and heat kills batteries as well.
[doublepost=1483377110][/doublepost]additionally.... i used that 2011 machine for 3d gaming for some time also. so it did spend a significant portion of its life on AC, running the CPU and GPU pretty hard, generating a lot of heat. CPU/GPU temps were often above 80-90 degrees for hours at a time.
This references the work of Jeff Dahn previously mentioned in this thread.
"Unfortunately I don’t know of any cell phones or laptop manufacturers that make 80-90% charging easy, likely because they’d rather just sell you a new product in a couple of years. But if you won’t be using the device for a while, make sure it isn’t charged all the way up before your turn it off and stick it in a drawer. Your battery will thank you."
https://electrek.co/2018/05/04/are-you-killing-your-lithium-batteries/
"Unfortunately I don’t know of any cell phones or laptop manufacturers that make 80-90% charging easy, likely because they’d rather just sell you a new product in a couple of years. But if you won’t be using the device for a while, make sure it isn’t charged all the way up before your turn it off and stick it in a drawer. Your battery will thank you."
https://electrek.co/2018/05/04/are-you-killing-your-lithium-batteries/
Been touting this stuff for years on this forum, but get told I'm just blowing bull poop. Thanks for the link. My old Lenovo laptop has this and the battery is still going strong after 5 years. Not bad for <$500 cheapie from best buy...
Wow cool - a battery thread! . I'm a huge OCD battery fan - hobbyist only. I've created detailed excel spreadsheets of my battery usage on my iPhones and been part of coconutBattery for years and years. I even participated in this: http://www.ifweassume.com/2013/08/the-de-evolution-of-my-laptop-battery.html for years. I've read Isidor's book several times and even conversed with him via email a few times - http://batteryuniversity.com/buy http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
Batteries are meant to be used - Apple does an above average job at managing batteries versus most companies. My Dell Laptop had a setting where I could turn off charging the battery at 80%. Problem is, Windows went nuts with that and although it said 80% charge, I'd pull out the charger and poof laptop would shut off because it was really at 0% but Windows power management and Dell's power management software were so poorly talking to each other. So, I had to turn that off.
Yes, doing 40-80% charge usage will extend the life of a battery. Keeping a battery at 100% all the time isn't optimal but Apple does do the 95%-100% thing that Weaselboy was talking about - that helps.
I personally would love some way to just use 40-80% of my Macbook Pro's battery. But in reality? My Macbook Air 2015 was used almost every day and spent most of its life plugged in - only had 100 cycles and still had 97% capacity left.
So I'm not going to worry about my Macbook Pro that I just got because by the time I'm going to sell it back, it should have near no battery capacity loss. For $200 I can get a new battery if I decide to keep it for more than 5+ years.
Love how my Macbook Pro is right now sitting at 96% and running off of the charger completely, not touching the battery. Would love the ability to put it at 50% and run off charger only - but I'm not too sad about that. Apple won't waste time just making a tiny segment of customers happy. Simplicity is key.
Hints: To those who plug in their laptops all the time - drain it down to 40% every now and then to keep the cells healthy and active. Isidor's book shows how doing this can restore some lost capacity from non-use.
. I'm a huge OCD battery fan - hobbyist only. I've created detailed excel spreadsheets of my battery usage on my iPhones and been part of coconutBattery for years and years. I even participated in this: http://www.ifweassume.com/2013/08/the-de-evolution-of-my-laptop-battery.html for years. I've read Isidor's book several times and even conversed with him via email a few times - http://batteryuniversity.com/buy http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteriesBatteries are meant to be used - Apple does an above average job at managing batteries versus most companies. My Dell Laptop had a setting where I could turn off charging the battery at 80%. Problem is, Windows went nuts with that and although it said 80% charge, I'd pull out the charger and poof laptop would shut off because it was really at 0% but Windows power management and Dell's power management software were so poorly talking to each other. So, I had to turn that off.
Yes, doing 40-80% charge usage will extend the life of a battery. Keeping a battery at 100% all the time isn't optimal but Apple does do the 95%-100% thing that Weaselboy was talking about - that helps.
I personally would love some way to just use 40-80% of my Macbook Pro's battery. But in reality? My Macbook Air 2015 was used almost every day and spent most of its life plugged in - only had 100 cycles and still had 97% capacity left.
So I'm not going to worry about my Macbook Pro that I just got because by the time I'm going to sell it back, it should have near no battery capacity loss. For $200 I can get a new battery if I decide to keep it for more than 5+ years.
Love how my Macbook Pro is right now sitting at 96% and running off of the charger completely, not touching the battery.
Would love the ability to put it at 50% and run off charger only - but I'm not too sad about that. Apple won't waste time just making a tiny segment of customers happy. Simplicity is key.Hints: To those who plug in their laptops all the time - drain it down to 40% every now and then to keep the cells healthy and active. Isidor's book shows how doing this can restore some lost capacity from non-use.
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Dang. My Note 8 battery is at 89% and only 8 months old
[doublepost=1525759602][/doublepost]IF battery is an issue I would just get Apple care which I would do anyways and just use it as intended and replace battery right before the expiration of apple care and you'll be fine for years
I think it is safe to assume there is no software for this. I've had Dell and Lenovo laptops that have this built into them, but it is poorly managed and implemented. As far as I know, there isn't a real trusted way or any way that I know of, of doing this on a Mac.
Yep...definitely not yet. Still doesn't mean there couldn't be software in the future. Since Hackintoshs are a thing I don't see why it couldn't be done on a MacBook. It would most like involve clover and require a bit of knowledge patching, but not impossible.
I sure would use it if there was one out there. I’d even pay for it. Hope it happens!
Yeah macrumours is the wrong place to ask any technical questions. 99% of the people who have no detailed tech knowledge but still will chime in to tell you their opinions. Lithium Ion batters don't like being fully discharged or fully charged, avoiding both of these extremes extends your battery life. There is no discussion or argument on this fact but here we are an entire thread arguing that point..
Yeah macrumours is the wrong place to ask any technical questions. 99% of the people who have no detailed tech knowledge but still will chime in to tell you their opinions. Lithium Ion batters don't like being fully discharged or fully charged, avoiding both of these extremes extends your battery life. There is no discussion or argument on this fact but here we are an entire thread arguing that point..
The moral of the story is: if you want to have full manual control and micromanage your machine, don’t buy a Mac. Nothing to do with “technical” questions. It’s plainly dumb to pay a lot of money für hardware that comes with all these automated sophisticated management features and then want to turn them off because of paranoia. And of course, this is a waste of time anyway since the battery controller is smarter than the user and will make sure that the battery is kept at optimal health.
To some extent. True optimal health would be only charging to ~70% capacity, and then slowly raising that capacity as the cells wear, as done in electric cars, but for a small portable consumer device, I don't think any manufacturer would want to take the battery life hit and be seen to be a worse product on 'spec sheet'
I agree and so does this pot smoking guy below...Yeah macrumours is the wrong place to ask any technical questions. 99% of the people who have no detailed tech knowledge but still will chime in to tell you their opinions. Lithium Ion batters don't like being fully discharged or fully charged, avoiding both of these extremes extends your battery life. There is no discussion or argument on this fact but here we are an entire thread arguing that point..
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I am working for electronic engineer with experiment of apply li-poly battery on products.
As Apple use 3.8v charge up to 4.35v HV battery and designed it for 1000 cycles @80%,
If you can discharge-change to 20% - 80% you get double life of battery which extend to 2000 cycles.
If you 30%-70% you can extend the life to above 5000 cycles.
It the tactic of automotive and aeroplane industrial for enhance battery lifespan.
However, you can not control the charging level by software as it controlled by the firmware on charging IC unless you rewrite the firmware of battery control IC.
For MacBook, avoid discharge the battery lower that 20%,
running the battery at least few hours for every week is enough to maintain lifespan of battery.
Battery will degrade fast when operate temp higher that 40C (100F), avoid use MacBook on very hot environment.
The worst case is remain battery full charge and use the AC power forever, the battery chemical will fading fast and swollen.
As Apple use 3.8v charge up to 4.35v HV battery and designed it for 1000 cycles @80%,
If you can discharge-change to 20% - 80% you get double life of battery which extend to 2000 cycles.
If you 30%-70% you can extend the life to above 5000 cycles.
It the tactic of automotive and aeroplane industrial for enhance battery lifespan.
However, you can not control the charging level by software as it controlled by the firmware on charging IC unless you rewrite the firmware of battery control IC.
For MacBook, avoid discharge the battery lower that 20%,
running the battery at least few hours for every week is enough to maintain lifespan of battery.
Battery will degrade fast when operate temp higher that 40C (100F), avoid use MacBook on very hot environment.
The worst case is remain battery full charge and use the AC power forever, the battery chemical will fading fast and swollen.
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Yeah macrumours is the wrong place to ask any technical questions. 99% of the people who have no detailed tech knowledge but still will chime in to tell you their opinions. Lithium Ion batters don't like being fully discharged or fully charged, avoiding both of these extremes extends your battery life. There is no discussion or argument on this fact but here we are an entire thread arguing that point..
Ya agreed, it's a public forum after all. Anyone can join and write as they please. I wonder how many people who say, 'just use it, don't worry about it' have the technical background to give that kind of advice. I would dismiss that kind of advice.
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