Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

mikeray

macrumors regular
Original poster
Jan 17, 2006
216
72
Brooklyn, NY
Just got my new MacBook. the Battery is at 70%. Does it matter whether I charge it now to full, or wait until it is fully drained to charge it?
 
Just got my new MacBook. the Battery is at 70%. Does it matter whether I charge it now to full, or wait until it is fully drained to charge it?

I'm no expert but I've read in many places that its a good idea to not let your Mac fully discharge : plug in at 30% would be ideal ...and extend battery life ... :)
 
Charge it all the way out of the box, you can still use it while its charging. Than use it off the charger and let it get down to a low amount for the first time. Somewhere around 15%-20%. Charge her back up and try to get it on a charger before it drops below 50% from there on out if you can.

Once a month roughly let it drop down to a low percent to allow the battery to get exercise if you have it plugged in a lot. Same thing, around 15%-20%-ish, just once a month.

I have never had a battery fail on me, hell never had a battery in any macbook go below 90% health. This is how you exercise Lithium-ion batteries ;)
 
  • Like
Reactions: hc_mty
What I would do is pretty simple.

Set the low battery warning at 20%.

Than charge the laptop to full whenever I get warned.

Then unplug.
 
I would charge it when it came and keep it plugged in if power is available. Use it off battery when no power is available and forget the discharge crap.

You want to avoid cycles to extend battery life. If you use your device all the time just charge it when you want and move on with more important things in life;)
 
I would charge it when it came and keep it plugged in if power is available. Use it off battery when no power is available and forget the discharge crap.

You want to avoid cycles to extend battery life. If you use your device all the time just charge it when you want and move on with more important things in life;)

This is really the best advice. If you can use it staying plugged in, do that. It will make the battery last as long as it possibly can. Otherwise, just use it!
 
If you can use it staying plugged in, do that.


I know there is a lot of back and forth on this subject, but as far as that specific technique goes, don't people advise against having it connected continuously while at 100%?
 
I know there is a lot of back and forth on this subject, but as far as that specific technique goes, don't people advise against having it connected continuously while at 100%?

It actually is the best thing for the battery. If you keep it charged 24/7 apple recommends to let it drain once a month. It was bad for "old school" batteries.
 
How do you change the low battery warning?


I am guessing you would need an app of some kind. Maybe "Low Battery Saver." Says it can provide an extra battery warning of your choosing on lifehacker

----------

It was bad for "old school" batteries.


Ahhh that makes since, especially considering I am currently on a 2008, so that advice might have been stored subconsciously as I am most definitely on an "old school" battery. Thanks for clearing that up
 
I know there is a lot of back and forth on this subject, but as far as that specific technique goes, don't people advise against having it connected continuously while at 100%?

No...
Not if those people understand a little about how the charger operates.
It stops charging when the battery is fully charged.
If you choose to use your Macbook while it is still connected and fully charged, then do it - there's no tech reason to unplug.
Same thing for idle, or sleeping. There's no particular advantage to unplugging at a full charge - it is your choice.
 
from what ive read, you dont want to leave it plugged in and ideally you dont want to charge above 80%..... but im no expert and people seem to have differing opinions. will see if i can find the link to this theory

EDIT:
On the other hand, you can read articles online that;ll say:

"When plugged in, the battery is not in use. The laptop’s power circuitry bypasses the battery unless it’s needed. Depending on how smart the charger is, it may occasionally poll and “top off” the battery if its charge decreases to a certain threshold below 100%, but this is rarely needed in practice."
 
from what ive read, you dont want to leave it plugged in and ideally you dont want to charge above 80%..... but im no expert and people seem to have differing opinions. will see if i can find the link to this theory

That was more advice for old laptops. Think of all the people who use clamshell mode, the laptop has to be plugged in. I have been doing this for a few years and have never had a battery go bad on me :)
 
No...
Not if those people understand a little about how the charger operates.
It stops charging when the battery is fully charged.
If you choose to use your Macbook while it is still connected and fully charged, then do it - there's no tech reason to unplug.
Same thing for idle, or sleeping. There's no particular advantage to unplugging at a full charge - it is your choice.

What you're saying is true. But do you know that as you fill a battery, the more charge it has, more power is necessary to charge it, and that heats up the battery more.
 
What you're saying is true. But do you know that as you fill a battery, the more charge it has, more power is necessary to charge it, and that heats up the battery more.

eh, yes? Are you trying to convince users that batteries should never be fully charged (heat is our enemy :D )
In my experience, the temperature increases because of the charging process. It is consuming energy, which will be partly converted to heat. The charger will also heat up. Longer charging time equals more heat.
When fully charged, the battery will cool back down, and the charger will also run somewhat cooler from that point, as it is no longer providing as much current.
 
eh, yes? Are you trying to convince users that batteries should never be fully charged (heat is our enemy :D )
In my experience, the temperature increases because of the charging process. It is consuming energy, which will be partly converted to heat. The charger will also heat up. Longer charging time equals more heat.
When fully charged, the battery will cool back down, and the charger will also run somewhat cooler from that point, as it is no longer providing as much current.

If heat is the major enemy of the new MB battery it is doomed as with no fan to vent the heat, the case and batteries must get very warm.:(
 
Okay this topic is confusing me. I thought it was optimal to use it until the battery drains completely at 0% and charge it up back to 100% in order to keep the battery lasting longer?

Now you guys are saying to use it while unplugged and let the battery drain down to about 15%-20% before charging it up again. So which one is it?

I also heard that its also bad to use the computer plugged in while the battery is at 100%. Is this true? So that means I should never use my computer plugged when the battery level is at 100%?

I am treating this laptop like a mobile device such as my iPad and iPhone. So does this mean the battery will last forever if we always use this thing while plugged in? That means preventing it from draining by plugging it in once it hits 15%-20%. That way it will never cycle.
 
Last edited:
New MacBook - Should i let my battery drain fully or charge it all the way.

Ok to clarify things, and it's really simple:
Plug it in when you can. Use the battery as you need. Don't let it drop to 0%.

Use your MacBook as a tool, not a burden.

Technical info:
Older NiCd batteries had a "memory" effect. Cycling batteries to prevent that no longer applies.

The current Lithium batteries do not take deep discharges (<20%) well. Shallow charges (90%) create less wear than deep cycles charges because wear is cumulative.

Oh and tapatalk sucks because half my post was truncated in posting.
 
Okay this topic is confusing me. I thought it was optimal to use it until the battery drains completely at 0% and charge it up back to 100% in order to keep the battery lasting longer?

Now you guys are saying to use it while unplugged and let the battery drain down to about 15%-20% before charging it up again. So which one is it?

I also heard that its also bad to use the computer plugged in while the battery is at 100%. Is this true? So that means I should never use my computer plugged when the battery level is at 100%?

I am treating this laptop like a mobile device such as my iPad and iPhone. So does this mean the battery will last forever if we always use this thing while plugged in? That means preventing it from draining by plugging it in once it hits 15%-20%. That way it will never cycle.


Draining a battery completely is the best way to permanently kill your battery. A mac will shut down before it drains completely to prevent this from happening, but if you forget to charge it right away it will slowly drain to zero and kill the battery. I would never go much lower than 20%.

Best advice is to plug it in whenever practicable.
 
What you're saying is true. But do you know that as you fill a battery, the more charge it has, more power is necessary to charge it, and that heats up the battery more.

Most of the new devices actually DECREASE the charging voltage as the battery reaches close to being full. Many devices today will charge quickly to like 80% but take much longer to go from 80 to 100%. It is a battery saving feature.

This is why we still keep having battery threads. So much cr^p posted here.
 
Just got my new MacBook. the Battery is at 70%. Does it matter whether I charge it now to full, or wait until it is fully drained to charge it?
Unfortunately, there is a lot of misinformation being posted in battery threads, as too many people make up things as they go along, rather than read what the manufacturer has to say. Apple knows best how to care for the batteries in its products.

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.
The link below should answer most, if not all, of your battery/charging questions, including tips for maximizing battery performance. If you haven’t already done so, I highly recommend you take the time to read it.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.