Very true, batteries are temperamental things at the best of times ... as Samsung have found out to their cost – at least my MacBook hasn't caught fire!
Many thanks for your support all!
David
Hi Hogster, I will let you know my 2012 Macbook Pro Retina had the same issue even after a battery replacement. Back in June of this year I replaced my battery in my 2012 Macbook 15" Retina because it too was shutting off between 20-40%. I replaced it but I had the same problem with new battery but shutting off between 5 to 12%.
I tried the SMC and PRAM with both the original battery and the new battery. I tried disconnecting the battery too.
I also tried draining the battery from 100% to when ever it would spontaneously shut off then charging it back up after 5 hours of it being dead and not touching it. That was not successful either.
So I contacted iFixit where I got the new battery and they gave me these instructions and now my problems seem to have been fixed as of the last 2 days.
My battery with 58 cycles will drain to 0% and I also get the low battery warning too.
What's odd is I did the SMC and PRAM reset before with the old battery and the new battery with no success.
However two things I did not do previously, which may be why it worked this time, is the 'First Aid' treatment to the disk, and doing SMC with the PRAM one after the other. I also installed Coconut battery and ran activity monitor as per instructions below from iFIXIT.
I also, u
ninstalled 'battery logger' which I was using prior to coconut battery. I removed Apple's battery bar from the menu bar under Energy Saver in settings. I just did these two additional things as a side precaution.
Anyway read below and try the following out.
NOTE: Do the SMC and right after do the PRAM reset. So have your machine OFF, do the SMC, and while the machine is still OFF, do the PRAM next. But before you do any those, do the FIRST AID treatment under disk utility for your Mac's SSD.
I hope this helps because there are many people here who have had this issue and there doesn't appear to be one solution. Some have gone through multiple batteries, logic boards, AC adapters, and etc to fix this problem.
Read the email below from iFixit:
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Thanks for your order.
I'm sorry to hear about the trouble. I'm here to help! What was the original reason for the replacement and does the issue go away with the original battery reinstalled? Additionally, what version of MacOS are you running?
The good news is that we tested that battery in our bench, so it has the potential to be a well behaving battery. But, it just needs a swift kick.
To see if we can't get you up and running sooner than later, please try all of the following for me (even if you have done some of them already) in this order:
Please Note: For an extended version of these instructions please checkout our
Basic Maintenance page that may help eliminate the issues with your battery, and are just plain good practice for any Mac.
Please let me know if this was able to fix the issue. Please note that it may take
2-3 days before any behavior changes are visible.
If the above steps do not fix the issue, please reply with the following screenshots:
- Screenshot 1: Run CoconutBattery for me and send me a screenshot of the results.
- Screenshot 2: Open Activity Monitor and go to the Energy Tab, then take a screenshot after 1 full discharge (100% to 10%) of routine use. You'll need to leave Activity Monitor open for the entire time the computer is discharging from 100% to 10% so Activity Monitor can accurately log energy use for the full duration of the discharge.
