The answer for me has turned out to be exactly 6 years.
As you can see from the table above, my MacBook Pro is right at the cusp of reaching 1,000 charge cycles coincidentally on the same day (November 18th, 2016) that it was manufactured 6 years earlier. The battery is depleting right now as I type this post so the 1000th cycle will surely occur within the next few hours.
My MacBook Pro gets used very often and based on my rough calculations, I tend to discharge the battery every other day, on average. Fortunately, my battery is still in good health for the most part. The useable capacity has noticeably declined in comparison to the days when the battery was brand new. This is to be expected. Overall, for a six year old battery, I think this one is holding up pretty well! The battery is still capable of storing over 80% of its original design capacity. That’s not bad!
For those of you who have ever wondered how long a MacBook battery will last, feel free to use this six year timeframe as a rough estimate. Keep in mind I am a full time student, work two jobs that rely on a laptop, and travel with my laptop frequently (requiring me to work away from a desk with the laptop unplugged.) Your own mileage may vary.
Tips to Extend the Useful Life of a Lithium-Ion Battery
- Perform shallow discharges (Do not drain the battery to 0%)
- Avoid leaving it fully charged (100% isn’t great either, surprisingly)
- To calibrate the battery, fully discharge it once a month.
- Keep it cool (hot batteries degrade in health much quicker.)
- Recognize that lithium-ion batteries degrade with time regardless.
The reason I included the 5th tip in specific is because I think a lot of people make the common mistake of believing that if you take great care to only partially charge and discharge a battery, you think you will somehow dramatically extend its useful life. Personally, I have followed all of these tips with great care and as you can see with my MacBook Pro, the battery inside still functions well. Despite my efforts, it still lost 20% of its original capacity from age/usage alone and that difference has been extremely noticeable. Furthermore, I have experienced additional age-related hiccups with the batteries inside my netbook, camera, e-reader, and cell phone this year too. (ALL OF MY BATTERIES ARE FAILING ME AT ONCE!!! Where have I gone wrong???) 🙁
In all seriousness, I really try to follow the battery “rules” as best as I can but all of my batteries are starting to deteriorate very quickly! They are getting old, it isn’t their fault. Cycle after cycle, each one becomes weaker and weaker with use. Most of my gadgets were purchased between the years of 2010 to 2013 so the age of each battery is starting to show. It may seem unreasonable but in my head, I never fully processed that “rechargeable batteries” had a limited useful life. I guess I thought they would be endlessly rechargeable for years to come so this sudden drop in performance definitely came as a surprise to me. The change in performance is noticeable as time goes on.
BY THE WAY… I recently discussed the possibility of upgrading my Mac. If this thing’s declining battery performance wasn’t reason enough, check out what’s now happening to all of my charging cables. I thought Apple’s claim to fame was high quality products?