I tried looking around but was unable to find a source tha prove the above is true. Do you mind providing a link to your source?
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New MacBook - Should i let my battery drain fully or charge it all the way.
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I tried looking around but was unable to find a source tha prove the above is true. Do you mind providing a link to your source?
Ah thank you found that link
Here's the passage I've found that seemed relevant:
"When it reaches a full charge, the light on your MagSafe adapter will turn green. This indicates that it has stopped charging your battery and you are now running on A/C power with a fully charged battery."
I'm not sure if this paragraph meant that the Mac will switch to ac power only or that it's not using ac power at all. Does the charge for your battery ever drop to 99% after using it?
Actually, the text you're looking for is just before what you quoted:Ah thank you found that link
Here's the passage I've found that seemed relevant:
I bolded the text that answers your question.
Yes, if you use the battery, it can certainly drop to 99% or lower. I'm not sure what you mean by this.
No, Lipos and Lions do NOT like being continuously kept at 100%. Li-ion hybrid cars like to keep their batteries around 20-80% and never keep them continuously charged.
Below is a screen capture of my MBP 13. It's prior owner kept it at 100% charged for it's first year of it's life as when I got it it only had 10 cycles at over it's first 400 days of life. When I got it, the battery pack was already down to 87%. In the 2 years I've had it I've made it a point to not keep it plugged in continuously and it's only dropped 3% after adding a 100 cycles to it. OTOH, my rMBP regularly get 'exercised' and I usually charge them when they hit 20% or so. My 3 year old rMBP 15 with over 300 cycles still has 94% of it's total battery capacity while my same vintage MBP 13 has only 84% left of it's original capacity.
I see this all the time as I race electric RC cars with lipo batteries for fun along with 700 Class RC Heli's that use 12 cell lipo battery packs with a total capacity of 5000 mah for each cell. The battery packs that I've abused and leave at 100% capacity for weeks/months at a time have severely diminished total capacity and peak power output vs. the same model of battery packs that I've kept at 50-60% while in storage.
If you think I'm just blowing smoke out of you know where, Lenovo has a nifty app for their Thinkpads that's designed to keep the battery at <80% while plugged in to prolong it's life for laptops that are continuously plugged in which is common in the corporate world.
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87% battery health after a year is pretty standard. I had around 85% left after 3 years on an air I kept plugged in mon-fri for work in clamshell mode.
There are two possibilities in which that can happen. First, if you have a heavy enough workload that the AC adapter can't provide all the power required (such as during extreme gaming), your Mac can draw power from both AC and the battery, which would drain the battery to some degree. Second, any battery loses charge over time, even if not used. This can happen while plugged in, because it is not constantly being charged once it's full. The battery would have to lose enough charge to drop below the roughly 93% threshold before charging would resume. This process would take a while, as the battery doesn't lose charge quickly if it's not being used.
After reading all the posts in this thread I'm still confused on whether I should unplug my mac after it fully charges to 100% or leave it plugged in. Is there a simple and straight for this instead of all these different theories and stuff?
I just want to know whats the best and safest way to prolong my battery life. I am hearing conflicting answers to this matter.
I just want to know whats the best and safest way to prolong my battery life. I am hearing conflicting answers to this matter.
Once your Mac battery is fully charged, it stops charging, even if you leave it plugged in. That is a fact which is not subject to debate or interpretation. As has been stated many times, run on battery whenever you need to and plug it in whenever you can. You can plug or unplug any time you need to, regardless of the charged percentage, and you never need to completely drain your battery.
New MacBook - Should i let my battery drain fully or charge it all the way.
You are not exactly asking to solve a math equation. There is room for lots of interpretation. That said, many people that argue a certain side are using science to back up their theories. That said, many people here are convinced that newer batteries require no such action for preservance.
You are not exactly asking to solve a math equation. There is room for lots of interpretation. That said, many people that argue a certain side are using science to back up their theories. That said, many people here are convinced that newer batteries require no such action for preservance.
Leave it plugged in for 6 days out of a week. Take out the charger and run it down to about 20-30% and then charge it up again. Lipos like exercise. If you're going to leave it plugged in 24/7, I wonder why you even got this class of laptop.
I switch between my 2 rMBP for my job and if I'm not going to use one for several weeks while I'm on a trip, I'll drain the battery down to about 50% and then turn off the laptop (not sleep). Your battery will be much happier to be at that charge for an extended amount of time instead of 0% or 100%.
For everyone else just treat it like you would your iPhone. I doubt everyone has their iPhone plugged in 24/7.
Simple answer: plug it in often enough that you won't run out of power when you absolutely will need battery power. Don't leave it unplugged and draining for no reason. Do a "full discharge followed by full recharge" once every 20-30 charge cycles, or once every 3-4 months if you don't go through that many cycles that often.
A "charge cycle" is a set of 100% discharge/100% charge. Whether that is discharging in one go followed by charging in one go or discharging 10%, then recharging 5%, then discharging 25%, then recharging 30%, then discharging 50%, then recharging 10%, then discharging 15%..... Every time the battery has gone through 100%-worth of discharge/recharge, you have gone through "one cycle."
Modern Lithium Ion and Lithium Polymer batteries can handle "uneven charge/discharges" just fine. No reason to do anything special. The only reason to do a full discharge and full recharge is to have the computer recalibrate its state-of-charge sensor. You shouldn't need to do that very often.
A "charge cycle" is a set of 100% discharge/100% charge. Whether that is discharging in one go followed by charging in one go or discharging 10%, then recharging 5%, then discharging 25%, then recharging 30%, then discharging 50%, then recharging 10%, then discharging 15%..... Every time the battery has gone through 100%-worth of discharge/recharge, you have gone through "one cycle."
Modern Lithium Ion and Lithium Polymer batteries can handle "uneven charge/discharges" just fine. No reason to do anything special. The only reason to do a full discharge and full recharge is to have the computer recalibrate its state-of-charge sensor. You shouldn't need to do that very often.
Go here for instructions on maintaining the battery in your device:
https://www.apple.com/batteries/
End of thread. Nothing else to say, move on.
https://www.apple.com/batteries/
End of thread. Nothing else to say, move on.
To preserve the battery, your Macbook should be immersed in blood overnight at least once a month. Use human blood if available, and do not use the blood of any variety of drug addict. For best results, the blood should be kept at body temperature constantly.
New MacBook - Should i let my battery drain fully or charge it all the way.
I must have missed that one while reviewing the Apple battery health guide.
I must have missed that one while reviewing the Apple battery health guide.
You need access to the Dark Guide of True Apple Lore, which can only be grasped by reaching through the RDF without fear but with malice aforethought.
Sadly, that's been recently updated and in their excitement to tell us all about watch batteries they've removed the bits about extending battery lifespan.
Battery tech is basically the same as it was 5 years ago, so the way to treat the battery is unchanged. Run on battery when you need to and plug it in when you can. That's it. You don't have to drain it intentionally, drain or charge to any particular level, or any other special procedure. Just use it and enjoy your new Mac.