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Battery is at 100%. I start using the laptop and then I feel the back right side start to feel warm on my lap. Fans are not running. The Battery starts to drop fairly quickly. I will use it for awhile and then shut it down. The next time I use it this does not happen. Once when the battery was at 50% and I was using it .It got hot dropped to 30% and shut off. I charged it up to 100% and the issue did not happen again for a couple of days. Battery health says my battery has 558 cycles. It is a mid 2012 MacBookPro retina.
Sounds like your battery is going. download this app: CoconutBattery and paste a snapshot of the main window so we can see the batteries condition Adding images to an existing question
