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Kylebrod
10-12-2017, 01:25 PM
On all of my windows machines, I would set the laptop not to charge passed 80%. This had an amazing result on the lifespan of the batteries. Is there a way I can do this on OSX?

ManoaHi
10-12-2017, 03:42 PM
I've never tried that. Have you tried http://fruitjuiceapp.com which is available from the App Store. It doesn't limit the charge but notifies you when it gets to some limit that you set. But that app is $10.

pigoo3
10-12-2017, 03:57 PM
Interesting question. Not one we hear very often!;)

In the "old days" with older battery technology...you would probably never consider this sort of thing due to the "memory effect".

- Nick

IWT
10-12-2017, 03:59 PM
On all of my windows machines, I would set the laptop not to charge passed 80%. This had an amazing result on the lifespan of the batteries. Is there a way I can do this on OSX?

A warm welcome to Mac-Forums.

I intend no offence, but may I ask where you learnt that charging Lithium-ion batteries only up to 80% extended their lifespan?

This is contrary to the advice from Apple and most battery manufacturers.

Ian

Kylebrod
10-13-2017, 02:37 AM
Windows 10 by default now with most laptops will prevent it from charging passed 90% when plugged in. I'm not sure if it's to prevent overcharging; Although tesla's cars do the same thing. They only charge to 80% unless you set it not to. Apparently it does extend the lifespan. In my own experience it seemed to help too :)

IWT
10-13-2017, 04:12 AM
Windows 10 by default now with most laptops will prevent it from charging passed 90% when plugged in. I'm not sure if it's to prevent overcharging; Although tesla's cars do the same thing. They only charge to 80% unless you set it not to. Apparently it does extend the lifespan. In my own experience it seemed to help too :)

Well, one lives and learns; but what one learns isn't always the final word on a subject.

Wonder what other members here think? I suspect most charge their batteries over night, or whenever, up to 100% each time - iPhones, iPads, even Notebooks.

Now, there is some debate about how far one should let a battery discharge - views from "rarely below 50-60 per cent" to "wait till it gets into the red at 20 per cent" - which usually implies that there is no definitive answer!


Ian

Kylebrod
10-13-2017, 11:13 AM
From what I've heard, the battery is under the most stress when it's at a very low and very high percentage. I try not to let mine dip below 40. Strange how there's so much controversy over it.

MacInWin
10-13-2017, 11:26 AM
The LiIon battery in modern laptops is designed to take a full charge. That said, holding off a few percent of 100 might extend the battery life a very short time, but also means that each individual use of the battery is shorter than designed. And all LiIon batteries start to decay over time, accelerating at two years after manufacture (not service date, manufacture date). So while one could theoretically extend the battery life by only charging to 80% (that's overkill, in my book, but we can use it since it's been mentioned), the extension of the life will be relatively immaterial as the battery will start to decay anyway, just based on time since manufacture. The current batteries in Macs are rated for about 500-1000 cycles (100-0-100), so even if you pressed the battery hard by doing that every day, the life of the battery would be about two years. If you stay in the 100-50-100 range, the battery will last about 4 years, but in that four years you get the same "battery time" overall. Using the numbers Kylebrod suggested (80-40-80) the battery should last about 5 years, but again, the "battery time" is about the same. So it's a wash, really. Use the Mac the way you need to, the battery will most likely not be any better or worse for wear unless you really abuse it, and if that's what you need to do, that's what a portable is all about and you should be ready to invest in replacing the battery when it's no longer functional for you.

pigoo3
10-13-2017, 01:59 PM
...the extension of the life will be relatively immaterial as the battery will start to decay anyway, just based on time since manufacture.

Definitely agree with you Jake. The personal experience being...my 2011 17" MacBook Pro is now 6 years old...has a very low battery cycle count...and I know that my battery is swelling since my trackpad is getting harder & harder to physically click all the time. Just part of the experience of owning a laptop computer.:)

- Nick

Raz0rEdge
10-13-2017, 02:25 PM
From what I've heard, the battery is under the most stress when it's at a very low and very high percentage. I try not to let mine dip below 40. Strange how there's so much controversy over it.

Not necessarily, especially with the latest batteries. Windows had this silly feature where they would charge the battery fully and then if the mains was plugged in, would run off the battery till it dropped down to 75% or so and then charge again. They figured constantly cycling the battery would somehow make it last long. Every Dell machine I ever got from work needed a new battery within 8months to a year because I constantly had the thing plugged in.

One of the things a about certain machines is that they always draw power from the battery, so if the mains was plugged in, it was charging the battery and then power was going to the computer. Macs don't do that. THey charge the battery and work off the mains. If the battery is 100% charged, they stop charging (no trickle charging or anything) and work purely off the mains power. They seamlessly switch to battery when the power plug is pulled and just as seamlessly go back to mains when the cable is plugged in again..

Long story short, don't bother with anything that changes the behavior of your Mac, it's been designed by darn smart people who know what they are doing..

Kylebrod
10-13-2017, 04:39 PM
This right here is actually really useful information. My battery is a big concern to me because back in the day I had a laptop which the battery died, and even when plugged in it wouldn't power on until I replaced the battery. Hopefully that isn't a concern on a macbook. Also, I was expecting apple to charge even more than just $199 to replace the battery in a notebook. Guess there's not much sense in worrying :)
Thank you to everyone who responded.