Something’s wrong with the battery fuel gauge. The battery is almost fully charged, yet it displays little time left

Our fuel gauge, that measures capacity, learns with every charge.  So, it becomes more accurate over time.  To avoid the initial learning process, we ‘taught’ the battery through programming what it should show.  However, if a battery starts its life at low charge, this does not work.  Therefore, you get an issue like you are seeing.  There is nothing wrong with his battery.  The battery is just learning, and it will come right after 3-4 charge cycles. In the meantime, the most important factor is the runtime and how long his light lasts.