I definitely understand your concern with your battery on your MacBook Pro. I found a couple of resources that I think might help with this.
The first thing I recommend is resetting the System Management Controller (SMC) when the battery does not appear to be charging properly:
Resetting the SMC on portables with a battery you should not remove on your own
Note: Portable computers that have a battery you should not remove on your own include MacBook Pro (Early 2009) and later, all models of MacBook Air, and MacBook (Late 2009).
- Shut down the computer.
- Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
- On the built-in keyboard, press the (left side) Shift-Control-Option keys and the power button at the same time.
- Release all the keys and the power button at the same time.
- Press the power button to turn on the computer.
Note: The LED on the MagSafe power adapter may change states or temporarily turn off when you reset the SMC.
You can find the full article here:
I also recommend reviewing the following resources for more information about prolonging your battery life:
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