MacBook Pro rapid battery degradation I recently acquired a second-hand (new, for me) MacBook Pro Retina Mid-2012 model. Also, in the near past, I upgraded it to El Capitan, and it is currently on OS X 10.11.1 (15B42).

Last week, it worked flawlessly, and ran for several hours on its battery— until its battery suddenly stalled out charging at 59%, and it started immediately losing power when the the cord is disconnected.

In summary:


The battery suddenly stopped charging, and was stuck at 59%, which has since decreased to 56%. 
If I disconnect the charger, it shuts down immediately. 
The battery status is "Replace now" even though it worked nominally last week and only reports having had 65 cycles. I believe it briefly read "Service battery" before that.


I have reset both the NVRAM and the SMC twice apiece. I am going to try to scare up another charger next. Does anyone have any further suggestions to try before paying the money for a battery replacement?

My previous experience with old MacBook batteries has been that they have slowly degraded to the point that they would only hold a charge for a few minutes, rather than suddenly dropping from nominal performance to complete inability to charge the computer, so I suspect the issue is not an old battery, and paying to replace it may not fix the problem.

I share the same problems with this question, however I don't have a warranty to fall back on:
New MacBook Pro slow performance, battery not working
Most likely, the battery is the issue. However, there is no way a battery should last only 65 cycles before it died. Most likely you have a defective battery. 

Even if you don't have a warranty, Apple will probably give you a new battery if you complain, since the current battery died way before it should have. They usually cover obvious defects even if the computer is out of warranty.

The other possibility is that the previous owner had something done to the battery at some point, and the work was done incorrectly. 65 cycles seems abnormally low for a 2012 laptop, unless the previous owner never used the computer.