Comment by marcan_42

If it's literally dying at 30% with no warning, it's either the battery polling being too slow (keep in mind the UI will usually only refresh once a minute or so for these things; the power management system has faster stats), or the charge estimation being way off. There's very little reason for a battery to drop from true 30% SoC to completely dead, without first going into a power draw spiral of doom which you can revert if you stop consuming as much power.