Best Battery Strategy

Kayan

macrumors 6502
Original poster
Jul 7, 2010
467
5
CA
This thread applies to any electronic device, but I’m talking specifically about the MBP. In terms of battery longevity, there are a few general things that I know will help preserve life:
  1. Batteries last longer when their charge is not extreme (maintained between, say, 30-80% charge)
  2. They last longer at cooler temperatures (not too cold, I’m not recommending a freezer)
  3. The less you use draw power from them, the less cycles put on, so they will last longer
I’ve seen many other tips, but most of them can be derived from these more basic principles. What I’d like to do is explain my strategy for preserving battery life, and see what all the battery baristas on here think about it. Note, my strategy only works if you have more of a desk job where you can generally dictate when to charge or not. People on the go will need a different approach.

Based on these things, my strategy is I never charge my device overnight. It’s pointless to me: why charge the battery to extreme full charge when I’m not using my device? It makes much more sense to not charge it overnight, take it to work, then plug it in when I’m at my desk actually using it. When I do this, it means that I am using the outlet instead of the battery for power as well as I am charging the battery at a slower rate, so I maintain more time in the middle range of the battery. Then when the battery is approaching 80-90%, I just unplug it, use it a little more, then go home. This way I’ve shifted the main power load from my battery to the outlet.
 

Howard2k

macrumors 68030
Mar 10, 2016
2,564
1,827
I just use it. $250 every three of four years is just not worth that much worry.

I like your strategy. You're also using your employer's electricity over your own too, so that's probably going to save you $4 or $5 over the term too. :)
 

juano

macrumors newbie
Nov 16, 2018
4
0
Hello,

Your strategy seems nice. I would like to add some some details on battery ageing behaviors:

1)As you mentioned, batteries last longer when they are used in small states of charge intervals (40-60%). Using the battery at high
deep of discharge (0-100%) considerably increases the ageing rate.

2) Best temperature for a battery is 25C. For a same applied current, low temperatures have a higher impact on capacity loss than higher
temperatures (low temp=<10C, high temp>35C). However, in a storage condition(no current applied), high temperatures have a
considerable higher impact.

3) Concerning the point of charging while using laptop against when it is turned off, the answer is not easy. If your laptop temperature is
high when you are charging it, the combination on high temperature+ low current can have a bigger impact on the capacity loss than
charging at lower temperature(lets say 25) and higher current.

4) Finally, a thing to avoid is charging the battery when the temperature is low.
 

Conutz

macrumors regular
Oct 24, 2014
203
113
Joburg
I just use it.
I agree with this, don’t over-analyze. Do what is most logical at the time and go from there. Besides, to discharge and charge every day for the sake of it is going to take more out of your battery than keeping it on the charger. If you’re running 25% per day, that’s a cycle every four days.

Apple will have designed the charging system to keep the battery in good shape - you’ll probably find that a good number of notebooks spend most of their lives on mains power, so they will have designed for this. Also, your workflow doesn’t seem to require significant time on battery, so it’s almost a moot point. Just use and chill!

I agree with unplugging when not in use though (zero benefit, unless it needs a charge) and also with keeping the battery cool (this is one of the reasons I never use clamshell mode).
 
  • Like
Reactions: BigMcGuire

alecgold

macrumors 65816
Oct 11, 2007
1,100
546
NLD
Just use the bloody tool until it needs service, repair or replacement.

I use it daily, hard and long to earn money. Micromanaging on this level will make my life miserable and cost me more money than it will ever save.

Just one more thing: if you plan to use it daily at your desk only, why care about the battery at all? Or why not buy a Mac mini?
 
  • Like
Reactions: gnasher729

Conutz

macrumors regular
Oct 24, 2014
203
113
Joburg
Just one more thing: if you plan to use it daily at your desk only, why care about the battery at all? Or why not buy a Mac mini?
That’s the thing about a desktop vs. a portable: a small decision at purchase time conditions you for the life of the product. Yes, obvious, I know - but having a portable & battery-powered device comes in really handy, and if not today, tomorrow it will. No need to worry about power dips, can decide to work from anywhere, anytime and so on. Unless one has a specific need for a desktop and doesn’t already have a portable device, I’d say careful consideration is required.