Have a question that has been bugging me. How to best preserve my Macbook Pro's battery life...................
Hello - as you can imagined this has been an oft asked question ad nauseum - a little searching on this site & some googling on the web (especially for Apple support articles) will likely provide you w/ plenty of information.
I have a MBPro (early 2013) - overall battery health is most dependent on the number of recharging cycles your battery has experienced (a cycle is defined as a nearly complete discharge & complete recharge; of course, this could be done at one time or over a number of partial discharges/recharges) - your battery should be in pretty good shape after even hundreds of complete recycles (won't be specific since varies w/ the computer), and then declines - look
Here (and the links) for more information.
You can check the number of 'cycles' that your battery has gone through and also the relative health by viewing the 'System Report' - attached is a screen capture from my laptop showing the battery's condition - notice the blue arrows showing the number of cycles, reported condition, and a ratio of mAh that can be calculated that will provide a percentage of remaining health of your battery; after 18 months, my battery is in pretty good shape. I also have a battery app that reports similar information that I've tabulated in Notes - so yet, another screen capture showing only 204 cycles and a 97% battery health - easy to track.
NOW, for an answer to your question - my advice is to keep your laptop plugged in as much as possible (mine sits by my den chair and rarely is unplugged) - now occasionally running down the battery is suggested to re-adjust the battery monitoring - I do this about twice a month when our maids show up and I sit on my 4-season porch. BUT, regardless of your practices the battery is likely going to outlast the useful like of the laptop if you want a new one every 3-5 years - computer owners really seem too worry to much about this issue - but hey, just my 2 cents, but I've thought about it!

Dave
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