It sounds like your battery is in bad shape. Your MBP goes to sleep and when it runs out of juice it simply dies.
If that's not the case - meaning the battery got's juice after a hard reset (holding power button for 5+ secs) without hanging to power supply then: First check if there are any Firmware updates. Then try the following:
Open up a Terminal in /Applications/Utilities/Terminal and to disable hibernation type:
sudo pmset -a hibernatemode 0
then remove any trace of previous hibernations:
rm /private/var/vm/sleepimage
After that reset the SMC aka System Management Controller:
MBP with removable battery:
- Shut down the computer.
- Disconnect the power adapter
- Remove the battery.
- Press and hold the power for at least for 5 seconds.
- Release the power button.
- Reconnect the battery
- Turn on the computer.
MBP with non removable battery:
- Shut down the computer.
- Plug in the MagSafe power adapter if not already connected.
- Press the Shift-Control-Option left side keys and the power button at the same time.
- Release all the keys and the power button at the same time.
- Turn on the computer.
The LED on the MagSafe may change states - if so it means your SMC reset was successfull. To enable Safe Sleep again open Terminal and sudo pmset -a hibernatemode 3
. Hope that help's.
Update
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