Not sure if there have been any changes that would cause this type problems, but I have also experienced the same type issues. Two different Olight flashlights with the AA Duracell batteries have leaked. These were newly purchased batteries, 10+ years in date, and had been in the device less than one month. One of the lights had been used twice or three times and is carried daily and the other had batteries from the same pack installed and had been lying on my desk. Attempted to use it during a brief power outage only to find it not working and upon checking it found the leakage. I have been able to salvage one of the two lights and hopefully I can fix the second. Never experienced this before and have used Duracell for the past 15 years.