> it dies [...] while thinking it's at 20% battery
This is definitely a manufacturing defect with your battery and you should take it in for warranty repair. It should never do that unless the battery is severely degraded (1000+ cycles)
Yep. Constantly says "service battery", too. I've made and cancelled a couple of service appointments due to Seattle basically shutting down for the snowstorms, hopefully I'll get it there at the next one and they will not wave me off with "oh just reset the nvram, also reboot your computer every week or so!" like they did the first time.
This is definitely a manufacturing defect with your battery and you should take it in for warranty repair. It should never do that unless the battery is severely degraded (1000+ cycles)