Best practices for my MacBook Pro 13" Retina's battery life/health

It is always good to at least once a month drain the battery completely then charge it back up to 100% to save the longevity of your battery.

https://www.apple.com/batteries/maximizing-performance/

Conventional wisdom from Nickel-Cadmium batteries was to discharge completely (or do so periodically to "condition" the battery and avoid the "memory effect".

With today's Lithium batteries, there is no memory effect, and deep discharge will shorten the battery's lifetime.

The MacBook is a tool to make your life easier. Use it the way it is most helpful to you, and do not be a slave to the wall outlet. It will run most of a day on battery, if that is what you need it to do.

Yes, there is a lot of conflicting info because there are different battery technologies. But lithium-ion in laptops over the past few years now tend to be the same, although there are different implementations of charge/discharge at the firmware level. In other words, some machines will automatically cut off charging around 80%, and stop the machine around 20% of capacity. This 80/20 rule is because it reduces the number of 'cycles' (and therefore reduces wear and tear).

The main thing is: relax. The Apple firmware and hardware looks after this, and you shouldn't worry too much. Personally, I too have a retina MacBook Pro 13, and I try not to let the battery discharge completely before recharging. But I wouldn't leave it charging overnight - always unplug it when it's charged.

I connect my Macbook to an external monitor, keyboard and mouse. This only works by keeping it plugged in to the power. But when I've finished working in this way, I will always unplug from the power to reduce wear and tear on battery. Even so, I have noticed a decline in battery life, from around 11 hours when I bought it (in late 2013) to 6-7 hours now. But that's still pretty respectable. I often take the machine into work, have a full day of working and browsing and some media playback, and it doesn't run out of juice - that's pretty amazing in my book.

Averythomas wrote:

It is always good to at least once a month drain the battery completely then charge it back up to 100% to save the longevity of your battery.

To totally discharge a battery in a MBP WILL shorten the battery life. That should be avoided.

Ciao.

marcopolomint wrote:

. But I wouldn't leave it charging overnight - always unplug it when it's charged.

That is not necessary. The OSX controls battery charging so the battery cannot be overcharged. Once the battery has been fully charged, the charger will supply power to the MBP but not the battery. As far as the battery is concerned, it would be the same as if the MBP were disconnected from the charger, ie: No incoming power.

Ciao.

Here is a list of all Apple support articles regarding power and batteries.

https://www.apple.com/support/macbookpro/batteries_power/

My rule of thumb is to use the MBP under battery power at least once per month to about the 40% charge level. When in portable mode, there will be times when the charge level becomes low. When you see a low battery warning, do terminate the session and find AC power. Do avoid the MBP from shutting down due to battery exhaustion. For technical information, refer to Battery University articles available in the Internet.

roebkerj wrote:

What about shutting down vs. sleeping if it isn't going to be used all day? All week?

Which ever you prefer will be fine. I shut down my MBP when I have finished a session. If you like to put the MBP to sleep, I would suggest a restart on occasion, perhaps weekly.

When in travel mode I suggest shutting the MBP down. There have too many instances where the user thinks the MBP is sleeping, only to find that not to be the case and the result is an overheated MBP.

Ciao.

Thanks Oglethorpe for the clarifications. I also have used and recommend Battery University, although there is a lot of technical information to sort through for the novice.

OGELTHORPE wrote:

marcopolomint wrote:

. But I wouldn't leave it charging overnight - always unplug it when it's charged.

That is not necessary. The OSX controls battery charging so the battery cannot be overcharged. Once the battery has been fully charged, the charger will supply power to the MBP but not the battery. As far as the battery is concerned, it would be the same as if the MBP were disconnected from the charger, ie: No incoming power.

I would err on the side of caution with this, as batteries are now built-in and non user-removable in all MacBooks. With a previous generation MBPro (2007) I was able to easily order and install a replacement battery when the original got to end of life (number of charge cycles). Of course, that is no longer possible, and could end up being very expensive to get Apple replacements. Over the 18 or so months I have had my Retina MBPro, the battery life has measurably degraded, so any opportunities to ameliorate that are worth taking, I think.

roebkerj wrote:

What about shutting down vs. sleeping if it isn't going to be used all day? All week?

Which ever you prefer will be fine. I shut down my MBP when I have finished a session. If you like to put the MBP to sleep, I would suggest a restart on occasion, perhaps weekly.

When in travel mode I suggest shutting the MBP down. There have too many instances where the user thinks the MBP is sleeping, only to find that not to be the case and the result is an overheated MBP.

Yeah, it's up to you: personally, I do the opposite, hardly ever shut it down (maybe once a week) and usually just put it to sleep at the end of a session and also overnight. The 'deep' sleep really helps with battery life, but I have instances like Ogelthorpe says where the battery has drained completely, but this is rare; and I have never had the overheating problem (that suggests background processes that might need shutting down).