When you had the computer taken apart and cleaned, what was the status of the battery?
If the battery has seen too many (one or more) 'run-flat scenarios' where the battery is ran
until the computer can barely be shut down, or reverts to sleep by itself; the end is nearer
than if you were to leave 30% life in the battery and just top it off, instead of running it flat.
• About Mac notebook batteries - Apple Support
• Apple Portables: Troubleshooting MagSafe adapters - Apple Support
Depending on how the computer is handled, the settings and user habits, and how often
the battery is cycled (charge-discharge-recharge) will directly cause shortness of its life.
A lower-power setting for the display, is one of the easiest things to save battery life; in
more than just one sitting, every thing you can do to conserve, helps. And some items
will also keep the computer running cooler, with several components lasting longer.
Some processor-intensive applications, or streaming video/music by wireless, can use a
fair amount of energy resources since some of them also invite temporary swap file use
that cycle data files to and from the storage drive. Less energy in that, with an SSD; still
a fair amount of energy if using the battery as primary source of power for those tasks.
The Console utility system logs may hold some clues about the battery and power status;
or what has been happening (cryptic language) that may be difficult to understand. The
Activity Monitor is an OK thing to look into at times; earlier versions seemed easier to see
what was happening. OS X has changed a bit; system resources still demand quite a lot.
There probably are some low-footprint apps that can show how the power reserves are
used; like those widget or graphic representations. In older OS X I'd preferred iStat Pro
since it had several handy references; the last versions weren't the same.
Conflicting software or mis-matched bits from older systems no longer supported may be
slowing down the computer, and items such as scanning antivirus or other poor utilities
can be using resources to help drain the battery unnecessarily & without an advantage.
Be sure to maintain additional backups of your computer contents to archives sustained
off-computer; and in addition to TimeMachine in external storage drive. To learn how &
use clones as an additional backup (alongside other methods) is a good idea. To reduce
odds of losing your content should the computer completely fail, and allow data recovery.
Good luck & happy computing! 🙂
