Add Samsung to the list - TabPro S sets to 85% 0r 100%. I only set it to 100% when on the road.
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How to limit the maximum charge to 70%?
- Thread starter thulium
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It does help a little that it lets it drop a bit. 60-80% SOC would be much better.
I disagree. All that would do is add unnecessary charge cycles and likely shorten battery life.
Apple used to have some business on their battery support page about exercising the battery by periodically running it on battery, and a year or so ago Apple removed that and no longer suggests the exercise routine.
Honestly, I think everybody obsesses a little too much over battery care. Just use it on battery when you need to be portable and plug it in and leave it alone when you don't. There is no need to fuss around otherwise.
Yes, no one is pointing a gun at our heads to improve battery management. Even knowing the benefits of better battery management isn't enough. If it is inconvenient, most people won't care. But considering what better battery management can save in money and recycling, it is wasteful.
If the computer is used on battery power a lot, it is a common misconception that more cycles would reduce life. I hinted at why in Post #22. Here's a simple (admittedly fictitious but correct in concept) example to illustrate.
Say you have a battery of 10Ah capacity and it is rated for 1000 cycles to 80% SOC. Average capacity is 9Ah. Multiply this by 1000 cycles and this equates to 9000Ah useable capacity.
Now let's handle the battery differently. We'll only charge to 80% SOC. The number of cycles to 80% of this reduced capacity increases dramatically to, say, 3000 cycles. Average capacity is 7.2Ah. Multiply this by 3000 cycles and this equates to 21600Ah. You can run the computer years longer on the same battery! The penalty is shorter run time between charges.
But even the above example is over-simplistic. It totally ignores the benefit of maintaining a lower average SOC. Batteries deteriorate with time without any cycling. The rate of this deterioration is greatly increased at higher SOC. So this adds to the benefit of shallow cycling.
You are way overcomplicating all this and what you are saying is the opposite of what Apple says.
Quote/excerpt from here:
Seriously, the quote doesn't contradict anything I have said and Apple is dumbing this down.
In case it wasn't clear, the life of the battery depends not just on the number of cycles but on the depth of the cycles and the time spent at high SOC.
And if you still have doubt on this, an excellent real-world example is how electric car manufacturers manage to provide an 8 year battery warranty on their cars using 18650 Li-Ion cells.
The quote directly contradicts what you said. I give up and I'll not reply further. If anybody wants to know what to do with their MacBook battery, they should follow Apple's recommendations at these links.
http://support.apple.com/kb/HT1446
http://www.apple.com/batteries/
I'm sorry. I'm at a loss to see where anything in your references contradicts the science or what I have said.
What you are missing is that Apple's recommendations are for maximizing the length of a discharge cycle, not for maximizing the useful life of the battery.
Apple will be telling you what to do in order to minimize warranty claims. They will be programming their controller to maximize battery life when running on AC.
I have a 2011 macbook pro battery with 90% charge that has had zero special treatment, spent most of its life living on AC, with no BS faffing about with trying to reduce charge, or try leave it at 80 percent, etc.
That machine is 5 going on 6 years old. Battery is fine.
Just use the machine and stop worrying about it. The hardware will probably die or be outdated long before the battery is significantly worn.
Good point about battery life generally coinciding with hardware obsolescence. Companies like Apple will use algorithms to get them through the warranty period and provide generally adequate life. They will ABSOLUTELY NOT use algorithms to maximize life as this is a trade off for run time which is a major selling point.
Sadly, I have a 2008 MacBook Pro with 0% of its original capacity and an early 2011 MacBook Pro with about 30% of its original capacity.. The dead battery in the 2008 MacBook is almost irrelevant because it is too old and slow anyways. But I'm in the category of people who would would rather have the longer run time at this stage in my 2011 MacBook's life. So Apple, provide this option for me and others in the same boat.
Good point about battery life generally coinciding with hardware obsolescence. Companies like Apple will use algorithms to get them through the warranty period and provide generally adequate life. They will ABSOLUTELY NOT use algorithms to maximize life as this is a trade off for run time which is a major selling point.
Sadly, I have a 2008 MacBook Pro with 0% of its original capacity and an early 2011 MacBook Pro with about 30% of its original capacity.. The dead battery in the 2008 MacBook is almost irrelevant because it is too old and slow anyways. But I'm in the category of people who would would rather have the longer run time at this stage in my 2011 MacBook's life. So Apple, provide this option for me and others in the same boat.
What was the usage profile for your early 2011? Mine has 88-90% battery capacity and is an early 2011 15" purchased in June-ish 2011. I gave it zero special treatment....
The other thing that blows my mind with people who get super paranoid about battery is this: if you're not using your battery for fear of wearing it out, why do you have a laptop?
If you can use your machine in AC power all the time or whatever, you're probably better off with an iMac or Mini...
If you need battery, use it. If you don't, don't.
Kinda like buying a nice car and putting it in the shed and never using it, but instead driving everywhere in a heap.... don't get it...
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It was used at home and at work - MacOS at home, Windows at work. At work, it was a desktop replacement. The 2011 MBP was rated at up to 7 hours on battery when new so it never had enough run time to avoid AC power over a work day. So at work it was plugged in most of the time. Limiting SOC to 60-80% in this application would have been much better for extending battery life.
The other thing that blows my mind with people who get super paranoid about battery is this: if you're not using your battery for fear of wearing it out, why do you have a laptop?
For me, it isn't a case of not wanting to use the battery. It is a case of not wanting to have it deteriorate prematurely due to being kept at an inappropriate SOC on AC power at my desk.
The situation improves a bit with the new MBP because of its longer run time. Using it at work without a connection to AC power will be more practical. It will be interesting to see how long in runs in Win10.
Well, I have always thought that moder batteries are just use-and-forget, but got suprised today when I checked the battery on my 2015 13" rMBP (bought April 2015) - 260 cycles and 84.9% capacity - to be honest I have expected less wear.
I use it connected to AC lots of time, tried to disconnect the power when not in use in the past, but because of stupid El Capitan bugs I often found the laptop losing 50-80% charge overnight (even when I shut down all the apps, nothing scheduled etc.)... So to be able to use the laptop on the road next day, I just kept the AC plugged in all the time, also when in standby. But apparently this is not that good in the long run.
I use it connected to AC lots of time, tried to disconnect the power when not in use in the past, but because of stupid El Capitan bugs I often found the laptop losing 50-80% charge overnight (even when I shut down all the apps, nothing scheduled etc.)... So to be able to use the laptop on the road next day, I just kept the AC plugged in all the time, also when in standby. But apparently this is not that good in the long run.
Yep. The longer this type of battery spends near 100% SOC, the more it will deteriorate. No charge/discharge cycles are required. Refer to Apple's own documentation here:
https://support.apple.com/en-us/HT201725
Even though they add to cycle count, shallow charge/dischange cycles will cause less deterioration in capacity over time than the extended high charge state.
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Nothing in Apple's documentation says this. If you don't need to be on battery, just leave it plugged it. It won't hurt anything.
You are just contradicting without supporting evidence. Here is some information for others.
Here is a direct quote from the referenced document that indicates the benefit of keeping a lower SOC for long periods:
"For computers that have non-removable batteries, you should either charge or drain the battery until 50% of the charge remains. If you plan to store the computer for longer than six months, charge it to 50% every six months that it remains in storage."
This is because of the more rapid deterioration that occurs at 100% SOC.
For a brief explanation, you can refer to this:
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
Note the effect of SOC, cycle depth and temperature on battery life. There are literally hundreds of other references available.
As it is a topic of interest for me due to my use of batteries in electric powered vehicles, I attended a lecture at McMaster University by Jeff Dahn of Dalhousie University on the topic in this video "Why do Li-ion batteries die and can they be immortal?" They do research on batteries for companies like GM. If you want to know more about what causes lithium chemistry cells to age and die, you will find this of interest.
You are quoting information about "storing" the computer (battery) and that has nothing to do with what is being discussed here. What is being discussed is how to treat a battery in a Mac portable that is being used.
This quote is right at the top of the Apple document you linked.
Readers should follow Apple's recommendations on how to use your MacBook's battery and not some random web site.
Again, you are just trolling. Apples recommendation here is not to keep the battery at 100% SOC. Listen to the lecture and read the references. In case you are confused, when you "store" a battery at a certain SOC it is no different than using it at the same SOC. So if you "use" it or "store" it always at 50% SOC it will last a lot longer than if you "use" it or "store" it at 100% SOC. It is that simple.
I am neither confused nor trolling. Read the link you posted for an explanation of what "store" means. I already posted the quote for you. Using your MacBook, whether plugged in or not is not storing it.
You are advocating people who are using their MacBook should somehow attempt to keep the battery at 50%. That is just absolutely ridiculous to even try and accomplish and is not recommended by Apple in any of their support documentation.
There isn't any difference between usage and storage from the battery's point of view when the battery is kept at the same SOC.
You are misrepresenting my position. What I am saying is that it is easy to increase the life of lithium ion batteries with different handling and that at least one of these options (lower SOC state option under AC power) should be made available to the user to suit their usage profile. Whether you or anyone else chooses to take any steps to increase the life of your batteries is totally up to you.
Actually there is, because the system will maintain the battery as required automatically.
People are lazy. People forget. People make bad judgement calls.
I guarantee that if Apple permitted/required that end users maintain their battery charge level manually the number of battery problems they would have to repair would skyrocket.
Apple have a battery charge retention policy of something like 1000 cycles / 3 years they will warrant the battery for. They program their controllers to meet this as best they can based on decades of experience with battery tech.
An end user is not going to do any better than this, guaranteed.
The power controller in modern Apple laptops is smart enough to offer near-optimal battery treatment without any user interaction. It will try to keep the battery at optimal charge levels and also cycle it slightly when used with power brick in order to prolong its life. I doubt it very much that you can do much better with manual micro-management.
Besides.
What's to say what apple call "100%" in the OS is not in fact actually closer to 80% of how far the battery could be pushed? For all we know apple is limiting battery to 80% of its actual capacity by design for battery longevity guarantees.
What's to say what apple call "100%" in the OS is not in fact actually closer to 80% of how far the battery could be pushed? For all we know apple is limiting battery to 80% of its actual capacity by design for battery longevity guarantees.
Just use the machine. Charge the battery when it's empty and use some more. Micromanaging will not provide any real-world benefit.
I have owned 2 macbook pros, and use both on the power brick, permanently connected 99% of the time. They function as desktop replacements.
The first one, a 2010, had the battery bloat badly, warping the case, in about 2 years. The keyboard and trackpad wouldnt work anymore but i had external input devices and kept using it till about the 3.5 year mark and retired it
The second one, a late 2013 model, had its battery bloat and interfere with the trackpad after 2.5 years. At the 3 year mark, i replaced the battery with a new one. I originally wanted to upgrade to the new macbook pro this year but was too disappointed with the nee model. So with the new battery, i will use my 2013 another year or so until apple gets their act together.
I only use the original apple charger which comes with the laptop and nothing else. My laptops have a relatively easy life plugged in, switched on, and running light loads 24/7
Like it or not, i do NOT believe simply leaving it plugged in is fine if you spend most of your time plugged in and used like a desktop replacment
I have since found a hack where if you block the middle pins on the magsafe connector, the charger will power the laptop but will not charge the battery. My battery was charged to 80% and is slowly draining down over time. Its been about 2 months and its sitting at just over 60% now.
The fact that i wont be able to hack the usb-c connection on the new macbook pros makes me less willing to buy them because i am quite sick of wasting time and money to replace bloated batteries or living with the consequences of not replacing then (losing the trackpad and sometimes even the keyboard due to bloat)
Sorry, but with my experience. I'm not simply letting apple manage my battery. Its obvious they're not doing everything we expect. After all, having a defective battery after a few years is a great way to get someone thinking about buying a new computer isnt it?
I will be the first person to throw money at any dev who can create an app or device that blocks charging to an MBP battery while still allowing the charger to power the laptop. If anyone knows of such a thing, please let me know where i can get one. Thanks
The first one, a 2010, had the battery bloat badly, warping the case, in about 2 years. The keyboard and trackpad wouldnt work anymore but i had external input devices and kept using it till about the 3.5 year mark and retired it
The second one, a late 2013 model, had its battery bloat and interfere with the trackpad after 2.5 years. At the 3 year mark, i replaced the battery with a new one. I originally wanted to upgrade to the new macbook pro this year but was too disappointed with the nee model. So with the new battery, i will use my 2013 another year or so until apple gets their act together.
I only use the original apple charger which comes with the laptop and nothing else. My laptops have a relatively easy life plugged in, switched on, and running light loads 24/7
Like it or not, i do NOT believe simply leaving it plugged in is fine if you spend most of your time plugged in and used like a desktop replacment
I have since found a hack where if you block the middle pins on the magsafe connector, the charger will power the laptop but will not charge the battery. My battery was charged to 80% and is slowly draining down over time. Its been about 2 months and its sitting at just over 60% now.
The fact that i wont be able to hack the usb-c connection on the new macbook pros makes me less willing to buy them because i am quite sick of wasting time and money to replace bloated batteries or living with the consequences of not replacing then (losing the trackpad and sometimes even the keyboard due to bloat)
Sorry, but with my experience. I'm not simply letting apple manage my battery. Its obvious they're not doing everything we expect. After all, having a defective battery after a few years is a great way to get someone thinking about buying a new computer isnt it?
I will be the first person to throw money at any dev who can create an app or device that blocks charging to an MBP battery while still allowing the charger to power the laptop. If anyone knows of such a thing, please let me know where i can get one. Thanks