Lezyne Mini Drive XL Charging and Battery Gauge Quirks

The Lezyne Mini Drive XL is a bright, 200 lumen, USB-rechargeable bike light that is small enough to throw in my pocket. I heard about it from a bike mechanic that I met while backpacking in Marin County. He was using it inside a clear nalgene-type bottle as a camp lantern and it was like a street lamp. I bought one as soon as I got back to civilization and it was great. Then one day I noticed that the battery indicator (constantly on; green/yellow/red/flashing red) was turning yellow minutes after a fresh charge. Weird, I thought; that’s supposed to indicate 50% or lower charge levels. I timed it from fully charged to dead and it lasted 2 hours and 40 minutes, which is 10 minutes past the manufacturer’s estimate. I carried on about my business for months, until one night I found myself far from home with a blinking-red, critical battery level. In this mode it reduces the power to save energy and ekes out half an hour of dim light. I plugged it into life support with my Anker Power Bank portable USB charger and gave it a full charge when I got back home. The next day the green battery indicator stopped coming on, instead replaced with a clear white light that I’ve never seen before because it doesn’t indicate any mode in the user manual. Although it still blinks green for charging, the ‘single button press while turned off’ action that quickly flashes the battery level no longer works unless it’s yellow or red. I’ve tried taking the battery out and pressing the power button a few times to try and reset the circuit. That didn’t change anything. I’ll post an update after I hear back from Lezyne.